<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Classification modeling based on surface porosity for the grading of natural cork stoppers for quality wines</style></title><secondary-title><style face="normal" font="default" size="100%">Food and Bioproducts Processing</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">Submitted</style></year></dates><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Abstract The natural cork stoppers are commercially graded into quality classes according with the homogeneity of the external surface. The underlying criteria for this classification are subjective without quantified criteria and standards defined by cork industry or consumers. Image analysis was applied to premium, good and standard quality classes to characterize the surface of the cork stoppers and stepwise discriminant analysis (SDA) was used to build predictive classification models. The final goal is to analyze the contribution of each porosity feature and propose an algorithm for cork stoppers quality class classification. This study provides the knowledge based on a large sampling to an accurate grading of natural cork stoppers.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Mechanical behavior of multilayered sandwich panels of wood veneer and a core of cork agglomerates</style></title><secondary-title><style face="normal" font="default" size="100%">Materials &amp; Design</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2015</style></year></dates><publisher><style face="normal" font="default" size="100%">Elsevier Ltd</style></publisher><volume><style face="normal" font="default" size="100%">65</style></volume><pages><style face="normal" font="default" size="100%">627-636</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Sandwich panels were produced using wood veneer of Aleppo pine as face sheets and cork agglomerate as core, including multilayered designs, for use in construction. The mechanical behavior of the panels was tested for perpendicular compression and tensile, longitudinal compression, three and four point bending, and shear. The load–displacement curves, patterns and cracking fractures were analyzed. The cork agglomerate provided a high performance under perpendicular compression, while the wood layers protected the core material and increased mechanical strength under tensile loads. Failure occurred mostly by fracture between cork granules. Multilayered sandwich panels showed higher strength and an increased number of layers improved the mechanical performance of the composite structure. The results suggested that these sandwich panels may be used as construction materials for paneling or partition walls in interior applications with the advantage of environmental friendliness and cost effectiveness.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Aliphatic bio-oils from corks: A Py–GC/MS study</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Analytical and Applied Pyrolysis</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2014</style></year></dates><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cork samples from Betula pendula, Quercus suber and Quercus cerris were submitted to Py–GC–MS/FID at temperatures between 550°C and 900°C and the pyrolysis-derived compounds (py-products) were identified and quantified. Corks were compared with wood samples. Py-products include suberin, lignin and carbohydrates derivatives. Suberin py-products are dominated by unsaturated aliphatics. Corks pyrolysis yield and composition were dramatically influenced by temperature in contrast to wood that showed stable results across temperatures. At 850–900°C the peaks area of cork pyrograms were approximately two times higher than at 550°C, for which yield was about half of the woods, and cork py-products were dominated by suberin-derived short chain aliphatics, namely 1-alkenes, while at 550°C composition was dominated by lignin derivatives. Lignin and carbohydrate derived products decreased dramatically over 750°C while the opposite was observed for unsaturated aliphatics. Cork materials show a high potential as feedstock for production of aliphatic-rich pyrolytic biofuels or as a source of olefins.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Monitoring intra-annual cambial activity based on the periodic collection of twigs - a feasibility study</style></title><secondary-title><style face="normal" font="default" size="100%">Dendrochronologia</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2014</style></year></dates><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This study aims at monitoring the cambial activity and xylogenesis along the growing season under Mediterranean climate using a newly designed sampling method based on the periodic collection of twigs from the crown, in order to test its efficacy. Ten species were selected; seven hardwood (Acer pseudoplatanus L.,Ceratonia siliqua L., Schinus terebinthifolius Raddi, Olea europaea L., Fraxinus angustifolia Vahl, Populus alba L., Quercus suber L.) and three softwood species (Abies alba Mill., Cupressus sempervirens L., Pinus pinea L.). The twigs were collected monthly during one year. After microtome sectioning and staining, the sections were photographed and analyzed to monitor ring development and the period of cambial activity. The twigs revealed large differences in radial growth, within and among species, which might be associated to their particular position in the tree, to the effect of the different crown microclimates, and/or to the crown conformation and type of leaves. The method showed effectiveness in the study of cambial activity, but limitations in the study of ring development due to impossibility of comparing samples. Improvements to the method are proposed, aiming essentially at minimizing the variability among samples.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Şen, Ali</style></author><author><style face="normal" font="default" size="100%">Van den Bulcke, Jan</style></author><author><style face="normal" font="default" size="100%">Defoirdt, Nele</style></author><author><style face="normal" font="default" size="100%">Van Acker, Joris</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Thermal behaviour of cork and cork components</style></title><secondary-title><style face="normal" font="default" size="100%">Thermochimica Acta</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cork</style></keyword><keyword><style  face="normal" font="default" size="100%">DSC</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus cerris</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus suber</style></keyword><keyword><style  face="normal" font="default" size="100%">suberin</style></keyword><keyword><style  face="normal" font="default" size="100%">TGA</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2014</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2014///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.sciencedirect.com/science/article/pii/S0040603114000902</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">582</style></volume><pages><style face="normal" font="default" size="100%">94 - 100</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Thermal behaviour of cork and cork chemical components was studied with coupled differential scanning calorimetry-thermogravimetrical analysis (DSC-TGA) in order to gain insight into the role of the chemical components on the thermal degradation of cork. Cork samples of Turkey oak (Quercus cerris) and cork oak (Quercus suber) were chemically treated to selectively remove inorganic material, extractives and suberin, to allow characterization of klason lignin and methanolysis-depolymerized suberin. Since Q. cerris cork granulates contain phloemic impurities, phloem from Q. cerris bark was also subjected to the same treatments as cork. The thermal decomposition of both cork species is similar, starting above 200°C and increasing with increasing temperature until ashing at approximately 485°C. TGA curves of both corks are almost identical but a detailed view on the differential thermogravimetry (DTG) and DSC curves shows that the two materials differ from each other. Two exothermal devolatilization and char combustion reactions occur, peaking at approximately 313°C and 445°C. These peak temperatures shift to lower temperatures in suberin-free and extractive-free corks giving evidence of the heat retarding effect of suberin and extractives and possible catalytic effect of inorganics in desuberinised cork. Phloem thermal degradation is similar to that of cork although exothermal peak temperatures are higher. Phloem-containing Q. cerris cork granulates thus show clear potential for high temperature applications.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Anjos, Ofélia</style></author><author><style face="normal" font="default" size="100%">Rodrigues, Cátia</style></author><author><style face="normal" font="default" size="100%">Morais, José</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effect of Density on the Compression Behaviour of Cork</style></title><secondary-title><style face="normal" font="default" size="100%">Materials &amp; Design</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Compression</style></keyword><keyword><style  face="normal" font="default" size="100%">Cork</style></keyword><keyword><style  face="normal" font="default" size="100%">Density</style></keyword><keyword><style  face="normal" font="default" size="100%">Dimensional recovery</style></keyword><keyword><style  face="normal" font="default" size="100%">Young’s modulus</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2013</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2013///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.sciencedirect.com/science/article/pii/S0261306913006663</style></url></web-urls></urls><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The compression properties of cork were studied for samples of different density. The densities were grouped into three classes: low density (0.13-0.15), mid density (0.15-0.19) and high density (0.19-0.25). The porosity of the cork samples increased from the low to the high density class, with porosity coefficients of 5.1%, 6.9% and 9.4% respectively. The difference in the porosity was associated with structural features, namely the presence of thick walled cork cells and the presence of lignified cells lining the pores. The stress-strain curves were similar for all cases, showing an elastic compression up to a yield point of about 5% strain, followed by a plateau with a small slope. The cork strength was higher in the radial direction than in the other directions. The density influenced the compression such that the corks with high density presented higher stiffness in compression in three directions: Young’s modulus was 17.4, 22.6 and 26.1 MPa for low, mid and high density corks respectively. This density effect was more evident in the plateau region of the progressive buckling of the cell walls (σ30 was respectively 1.07, 1.29 and 1.54 MPa for the three density classes). The recovery of dimensions after compression in each direction was also studied following compression to 50% strain. The recovery was on average 50% of the initial deformation on the first day, and almost total after 15 days. The recovery was higher for corks with low density and in non radial directions.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Brazinha, Carla</style></author><author><style face="normal" font="default" size="100%">Fonseca, Ana P.</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author><author><style face="normal" font="default" size="100%">Teodoro, Orlando M. N. D.</style></author><author><style face="normal" font="default" size="100%">Crespo, João G.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Gas transport through cork: Modelling gas permeation based on the morphology of a natural polymer material</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Membrane Science</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cork</style></keyword><keyword><style  face="normal" font="default" size="100%">Gas permeation</style></keyword><keyword><style  face="normal" font="default" size="100%">Knudsen transport</style></keyword><keyword><style  face="normal" font="default" size="100%">Natural polymers</style></keyword><keyword><style  face="normal" font="default" size="100%">solubility</style></keyword><keyword><style  face="normal" font="default" size="100%">Solution–diffusion model</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2013</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2013///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://linkinghub.elsevier.com/retrieve/pii/S0376738812007636</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">428</style></volume><pages><style face="normal" font="default" size="100%">52 - 62</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Natural polymers have been studied during the last years for the transport and separation of liquid and gas mixtures, in terms of solubility and permeability data, and their structure and mechanical properties have been characterised. However, no transport models have been reported, relating transport with the material morphology. Cork is a natural cellular material containing three structural polymers (suberin, lignin and polysaccharides). Cork is considered a natural polymer, with economic relevance due to its sealing, non-toxic, stable and low-density properties. Cork was characterised in this work in terms of its solubility and permeability data in relation to various gases with different molecular mass: He, O2, N2, CO2 and 1,1,1,2-tetraﬂuoroethane (R134a). A morphological analysis of the structure of the cork sample chosen in this work was also performed using SEM (scanning electron microscopy) and TEM (transmission electron microscope) image analysis, which took into account the variation of each relevant structural parameter. A transport model was developed supported on the morphology of cork characterised in this work. The transport model developed considers that gas permeation occurs through the plasmodesmata, which are channels with approximately 100 nm of diameter that cross the cell walls of the cork cells. It was found that gas transport follows a Knudsen mechanism, as proved by the gas permeability behaviour with increasing gas molecular mass, with a negligible contribution of viscous transport to the total ﬂux.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Fonseca, Ana Luisa</style></author><author><style face="normal" font="default" size="100%">Brazinha, Carla</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author><author><style face="normal" font="default" size="100%">Crespo, João G.</style></author><author><style face="normal" font="default" size="100%">Teodoro, Orlando M. N. D.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Permeability of Cork for Water and Ethanol</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Agricultural and Food Chemistry</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cork</style></keyword><keyword><style  face="normal" font="default" size="100%">diffusion</style></keyword><keyword><style  face="normal" font="default" size="100%">permeability</style></keyword><keyword><style  face="normal" font="default" size="100%">sealing properties</style></keyword><keyword><style  face="normal" font="default" size="100%">Sorption</style></keyword><keyword><style  face="normal" font="default" size="100%">water transport</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2013</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2013///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://dx.doi.org/10.1021/jf4015729</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">61</style></volume><pages><style face="normal" font="default" size="100%">9672 - 9679</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Transport properties of natural (noncompressed) cork were evaluated for water and ethanol in both vapor and liquid phases. The permeability for these permeants has been measured, as well as the sorption and diffusion coefficients. This paper focuses on the differences between the transport of gases? relevant vapors and their liquids (water and ethanol) through cork. A transport mechanism of vapors and liquids is proposed. Experimental evidence shows that both vapors and liquids permeate not only through the small channels across the cells (plasmodesmata), as in the permeation of gases, but also through the walls of cork cells by sorption and diffusion as in dense membranes. The present study also shows that cork permeability for gases was irreversibly and drastically decreased after cork samples were exposed to ethanol or water in liquid phase.</style></abstract><issue><style face="normal" font="default" size="100%">40</style></issue><notes><style face="normal" font="default" size="100%">doi: 10.1021/jf4015729doi: 10.1021/jf4015729The following values have no corresponding Zotero field:&lt;br/&gt;publisher: American Chemical Society</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Variability of the Chemical Composition of Cork</style></title><secondary-title><style face="normal" font="default" size="100%">BioResources</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2013</style></year></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">2246-2256</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The chemical composition of cork was determined, following a sampling that covered the whole production area in Portugal (29 provenances from six regions) with samples taken at cork stripping. To analyse between population variations, a more intensive sampling was made in two locations. The overall mean chemical composition of cork was: extractives 16.2% (dichloromethane 5.8%, ethanol 5.9%, water 4.5%), suberin 42.8% (long-chain lipids 41.0%, glycerol 3.8%), and lignin 22.0% (Klason 21.1%, acid soluble 0.9%). The suberin compositional ratio of long chain lipids to glycerol, LCLip:Gly, was 11.3. The proportion of neutral sugars in the polysaccharides was: glucose 46.1%, xylose 25.1%, arabinose 18.0%, mannose 3.0%, galactose 7.3%, and rhamnose 0.5%. The range of values was large and the variation between individual trees seemed to be the major factor of the differences. Geographical location of cork production was statistically significant only in a few cases when considering site and not when considering regions. The population variation in two sites was important and the absolute difference between the site mean values was small. This research covers the natural variability of cork’s chemical composition and discusses the contribution of the structural compounds to the variation of cork properties.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Aguado, Pedro L.</style></author><author><style face="normal" font="default" size="100%">Curt, M. Dolores</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author><author><style face="normal" font="default" size="100%">Fernández, Jesús</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Allocation of 14C assimilated in late spring to tissue and biochemical stem components of cork oak (Quercus suber L.) over the seasons</style></title><secondary-title><style face="normal" font="default" size="100%">Tree Physiology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">C-14 labeled compounds</style></keyword><keyword><style  face="normal" font="default" size="100%">carbon assimilation</style></keyword><keyword><style  face="normal" font="default" size="100%">microautoradiography</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus suber</style></keyword><keyword><style  face="normal" font="default" size="100%">suberin</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2012</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2012///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://treephys.oxfordjournals.org/content/32/3/313.abstract</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">32</style></volume><pages><style face="normal" font="default" size="100%">313 - 325</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Carbon distribution in the stem of 2-year-old cork oak plants was studied by 14CO2 pulse labeling in late spring in order to trace the allocation of photoassimilates to tissue and biochemical stem components of cork oak. The fate of 14C photoassimilated carbon was followed during two periods: the first 72 h (short-term study) and the first 52 weeks (long-term study) after the 14CO2 photosynthetic assimilation. The results showed that 14C allocation to stem tissues was dependent on the time passed since photoassimilation and on the season of the year. In the first 3 h all 14C was found in the polar extractives. After 3 h, it started to be allocated to other stem fractions. In 1 day, 14C was allocated mostly to vascular cambium and, to a lesser extent, to primary phloem; no presence of 14C was recorded for the periderm. However, translocation of 14C to phellem was observed from 1 week after 14CO2 pulse labeling. The phellogen was not completely active in its entire circumference at labeling, unlike the vascular cambium; this was the tissue that accumulated most photoassimilated 14C at the earliest sampling. The fraction of leaf-assimilated 14C that was used by the stem peaked at 57% 1 week after 14CO2 plant exposure. The time lag between C photoassimilation and suberin accumulation was ∼8 h, but the most active period for suberin accumulation was between 3 and 7 days. Suberin, which represented only 1.77% of the stem weight, acted as a highly effective sink for the carbon photoassimilated in late spring since suberin specific radioactivity was much higher than for any other stem component as early as only 1 week after 14C plant labeling. This trend was maintained throughout the whole experiment. The examination of microautoradiographs taken over 1 year provided a new method for quantifying xylem growth. Using this approach it was found that there was more secondary xylem growth in late spring than in other times of the year, because the calculated average cell division time was much shorter.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><notes><style face="normal" font="default" size="100%">10.1093/treephys/tps01210.1093/treephys/tps012</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Cellular structure and chemical composition of cork from the Chinese cork oak (Quercus variabilis)</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Wood Science</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2012</style></year></dates><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Quercus variabilis Blume, the Chinese cork oak, is an oak species with a thick cork outer bark. The cork is exploited at a limited scale in China and considered of lower quality than the commercial cork from Quercus suber. We studied an industrial cork granulate feedstock of Q. variabilis in relation to cellular structure and chemical composition and compared it to Q. suber cork under a material’s perspective. The cork of Q.variabilis has 1.1 % ash, 9.6 % extractives, 34.8 % suberin and 19.1 % lignin. The monosaccharide composition with shows a predominance of hemicelluloses: glucose 42.8 % of total neutral sugars, xylose 27.5 %, arabinose 15.4 %, galactose 9.0 %, mannose 4.0 %, rhamnose 1.2 %. The FT-IR spectrum shows the indicative peaks of suberin. The composition is overall similar to that of Q. suber cork. Q. variabilis cork has the typical cellular characteristics of bark cork tissues with a regular and radially aligned structure of cells without intercellular voids. Solid volume fraction was estimated at approximately 16 %. Compared with Q. suber, the Q. variabilis cork cells are smaller, the cell wall undulation and the overall row alignment less homogeneous, the cell surface is irregular and the solid volume proportion higher. The characteristics of Q. variabilis cork support its use as a cellular material for sealing, insulation and energy absorption, but the overall quality is lower than that of Q. suber cork. The negative impact of the higher density and structural lower uniformity at tissue and cell level should be evaluated for processing and product performance.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pereira, Ana Carina</style></author><author><style face="normal" font="default" size="100%">Brezet, Han</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author><author><style face="normal" font="default" size="100%">Vogtlander, Joost</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Cork and sustainability: Discussing the sustainable use of the material from a design perspective</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Shanghai Jiaotong University (Science)</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">cork products and materials</style></keyword><keyword><style  face="normal" font="default" size="100%">design and materials</style></keyword><keyword><style  face="normal" font="default" size="100%">eco-materials</style></keyword><keyword><style  face="normal" font="default" size="100%">Sustainability</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2012</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2012///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.springerlink.com/index/10.1007/s12204-012-1287-8</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">17</style></volume><pages><style face="normal" font="default" size="100%">360 - 363</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">There is the challenge to use materials in a more sustainable way. Even though cork has an interesting eco-proﬁle as a material, other aspects contributing to an enhanced sustainable use of the resource are discussed: addressing the life-span of products, materials substitution, and the trend of materials development identiﬁed. Key words: sustainability, design and materials, cork products and materials, eco-materials</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Costa, Augusta</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Drying kinetics of cork planks in a cork pile in the field</style></title><secondary-title><style face="normal" font="default" size="100%">Food and Bioproducts Processing</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cork</style></keyword><keyword><style  face="normal" font="default" size="100%">empirical drying models</style></keyword><keyword><style  face="normal" font="default" size="100%">Moisture content</style></keyword><keyword><style  face="normal" font="default" size="100%">moisture ratio</style></keyword><keyword><style  face="normal" font="default" size="100%">natural sun drying</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2012</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2012///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://linkinghub.elsevier.com/retrieve/pii/S0960308512000624</style></url></web-urls></urls><pages><style face="normal" font="default" size="100%">1 - 9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Moisture content is one important parameter in the trading of raw cork planks after harvesting. This study presents a mathematical modeling of the drying curve of raw cork planks in a cork pile in the ﬁeld, under natural sun drying conditions. Experimental data were obtained by following the water loss (i.e. by daily weighing) of 97 cork planks positioned in nine points within a cork pile. Immediately after harvesting, the raw cork planks had a mean moisture content in a dry basis of 40.4% and after 20-day drying 16.6%. The drying process of the cork planks showed three phases: drying was very fast in the ﬁrst 2 days; in the next 2–15 days there was a decreasing drying rate; and a ﬁnal phase, after 15 days in the cork pile, with a slightly decreasing drying rate. Mathematical modeling provided a direct relation between moisture content and drying time. After comparing sixteen empirical drying models, the Modiﬁed Henderson and Pabis model showed the best ﬁt. According to this model, the cork planks are commercial dry (14% moisture content in a wet basis) 15 days after harvest.</style></abstract><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;publisher: Institution of Chemical Engineers</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Lignin monomeric composition of corks from the barks of Betula pendula, Quercus suber and Quercus cerris determined by Py–GC–MS/FID</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Analytical and Applied Pyrolysis</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2012</style></year></dates><publisher><style face="normal" font="default" size="100%">Elsevier B.V.</style></publisher><pages><style face="normal" font="default" size="100%">1-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Samples of cork tissues separated from the barks of Betula pendula, Quercus suber and Quercus cerris were characterized by Py–GC–MS/FID in respect to composition of lignin. The pyrolysis temperature influenced the yield of pyrolysis products, and in the conditions usually applied to wood pyrolysis (550 ◦C) suberin is only partially degraded into products. The lignin composition of the three corks showed predominantly a guaiacyl-based lignin: guaiacyl (G) units represented 85.7%, 96.4% and 93.7% of lignin respectively in B. pendula, Q. suber and Q. cerris corks, while syringyl (S) units amounted respectively to 11.9%, 2.5% and 2.7% and p-hydroxyphenyl (H) units to 2.4%, 1.1% and 3.6%. Pyrolysis of the woods of these same species confirmed the GS character of their lignins in contrast to the corks G-lignin type. The influence of ferulic acid in the results and its integration in a heterogeneous cork lignin structure was discussed.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">NATURAL VARIABILITY OF SURFACE POROSITY OF WINE CORK STOPPERS</style></title><secondary-title><style face="normal" font="default" size="100%">Journal international des sciences de la vigne et du vin</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2012</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2012///</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">46</style></volume><pages><style face="normal" font="default" size="100%">331 - 340</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Aim : The aim of this study was to characterize the variability and to quantify the surface porosity of wine cork stoppers of different quality classes. Methods and results: The porosity of 300 cork stoppers was characterized by image analysis on the lateral surface and tops. Porosity coefficient was 2.4%, 4.0% and 5.5% for premium, good and standard stoppers, respectively. The lateral surface of stoppers was heterogeneous with respect to porosity features: the tangential regions presented higher porosity while the radial regions had larger pores. Conclusion : The quality classes of cork stoppers can be differentiated by the mean values of the main porosity features of their surface. There is a natural heterogeneity of the porosity features over the external surface of cork stoppers that can be traced back to the biological basis of cork formation and the production process. Significance and impact of the study: Natural cork stoppers are the premium product of the cork industry, with worldwide recognition of quality and performance as wine sealant. Due to the large sampling and detailed observation, the results presented in this study may be used for reinforcing quality requirements, e.g., with definition of standards to improve the classification system. A better understanding of cork intrinsic variability and of the anisotropy of porosity features shown by cork stoppers is important for performance development.</style></abstract><issue><style face="normal" font="default" size="100%">February</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Oliveira, Vanda</style></author><author><style face="normal" font="default" size="100%">Knapic, Sofia</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">NATURAL VARIABILITY OF SURFACE POROSITY OF WINE CORK STOPPERS</style></title><secondary-title><style face="normal" font="default" size="100%">Journal international des sciences de la vigne et du vin</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">image analysis</style></keyword><keyword><style  face="normal" font="default" size="100%">lateral surface</style></keyword><keyword><style  face="normal" font="default" size="100%">natural cork stoppers</style></keyword><keyword><style  face="normal" font="default" size="100%">Porosity</style></keyword><keyword><style  face="normal" font="default" size="100%">quality classes</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2012</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2012///</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">46</style></volume><pages><style face="normal" font="default" size="100%">331 - 340</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Aim : The aim of this study was to characterize the variability and to quantify the surface porosity of wine cork stoppers of different quality classes. Methods and results: The porosity of 300 cork stoppers was characterized by image analysis on the lateral surface and tops. Porosity coefficient was 2.4%, 4.0% and 5.5% for premium, good and standard stoppers, respectively. The lateral surface of stoppers was heterogeneous with respect to porosity features: the tangential regions presented higher porosity while the radial regions had larger pores. Conclusion : The quality classes of cork stoppers can be differentiated by the mean values of the main porosity features of their surface. There is a natural heterogeneity of the porosity features over the external surface of cork stoppers that can be traced back to the biological basis of cork formation and the production process. Significance and impact of the study: Natural cork stoppers are the premium product of the cork industry, with worldwide recognition of quality and performance as wine sealant. Due to the large sampling and detailed observation, the results presented in this study may be used for reinforcing quality requirements, e.g., with definition of standards to improve the classification system. A better understanding of cork intrinsic variability and of the anisotropy of porosity features shown by cork stoppers is important for performance development.</style></abstract><issue><style face="normal" font="default" size="100%">February</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Study of thermochemical treatments of cork in the 150–400°C range using colour analysis and FTIR spectroscopy</style></title><secondary-title><style face="normal" font="default" size="100%">Industrial Crops and Products</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2012</style></year></dates><volume><style face="normal" font="default" size="100%">38</style></volume><pages><style face="normal" font="default" size="100%">132-138</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A study of chemical transformations of cork during heat treatments was made using colour variation and FTIR analysis. The cork enriched fractions from Quercus cerris bark were subjected to isothermal heating in the temperature range 150–400 ◦ C and treatment time from 5 to 90min. Mass loss ranged from 3% (90min at 150 ◦ C) to 71% (60min at 350 ◦ C). FTIR showed that hemicelluloses were thermally degraded ﬁrst while suberin remained as the most heat resistant component. The change of CIE-Lab parameters was rapid for low intensity treatments where no signiﬁcant mass loss occurred (at 150 ◦ C L* decreased from the initial 51.5 to 37.3 after 20min). The decrease in all colour parameters continued with temperature until they remained substantially constant with over 40% mass loss. Modelling of the thermally induced mass loss could be made using colour analysis. This is applicable to monitoring the production of heat expanded insulation agglomerates.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Temperature-induced structural and chemical changes in cork from Quercus cerris</style></title><secondary-title><style face="normal" font="default" size="100%">Industrial Crops and Products</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2012</style></year></dates><volume><style face="normal" font="default" size="100%">37</style></volume><pages><style face="normal" font="default" size="100%">508-513</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The effects of temperature on anatomical and chemical characteristics of Quercus cerris cork were examined. Cork samples were subjected to isothermal air heating between 150 ◦ C and 400 ◦ C and analyzed for mass loss, cellular structure and chemical composition. The thermal decomposition of Q. cerris cork is similar to that of Q. suber cork. Cork is thermally stable below 200 ◦ C and after that degradation depended on temperature and heating time with increasing mass loss, i.e. 3% at 200 ◦ C 10min and 46% at 350 ◦ C 60min.With temperature and starting at 200 ◦ C, cells expanded, cell wall thickness was reduced and corrugations were lost. Extractives degraded at lower temperatures, although aliphatic extractives were found to be more stable. Suberin from Q. cerris was more heat resistant than Q. suber suberin, while lignin showed similar resistance. These results provide a basis for studies on the production of Q. cerris bark expanded cork agglomerates for insulation purposes.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">The cellular structure of cork from Quercus cerris var. cerris bark in a materials’ perspective</style></title><secondary-title><style face="normal" font="default" size="100%">Industrial Crops and Products</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2011</style></year></dates><volume><style face="normal" font="default" size="100%">34</style></volume><pages><style face="normal" font="default" size="100%">929-936</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cork in the outer bark of trees is among the valuable raw materials of biological origin due to properties that result mainly from its cellular structure. Large scale commercial utilization of cork has been only achieved with cork from Quercus suber. Another oak species, Quercus cerris, also contains substantial, albeit not continuous, regions of cork that are clearly visible to the naked eye but are so far considered as a waste material. Bark samples of Q. cerris var. cerris trees were collected from the Andırın province, Turkey. Cork portions were separated and their cellular structure was investigated with optical and electron scanning microscopy observations. The results were compared with Q. suber cork. Q. cerris cork has the typical features of cork tissues with a regular and radially aligned structure of suberized cells without intercellular voids, showing a ring structure and a distinction of earlycork and latecork cells. Solid volume fraction was estimated at 25% (22% in earlycork, 36% in latecork). In Q. cerris cork cells are smaller, cell wall thickness and solid volume fraction are higher, and the tissue is less homogeneous with a higher content of ligniﬁed inclusions than in Q. suber cork. These factors will negatively inﬂuence quality in regard to density and mechanical properties associated to elasticity. However, this does not impair its use for production of granulates and agglomerates, e.g. for insulation and energy absorption. Separation of the cork fraction from the bark is a step required before further processing and use.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Characterization of radial bending properties of cork</style></title><secondary-title><style face="normal" font="default" size="100%">European Journal of Wood and Wood Products</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2011</style></year></dates><volume><style face="normal" font="default" size="100%">69</style></volume><pages><style face="normal" font="default" size="100%">557-563</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The behaviour of cork under three point bending stress in the radial direction was evaluated in relation to porosity (range 2.0–15.4%) and density (range 0.160– 0.220 g cm−3 ). The study was made using water-boiled cork planks of two commercial quality classes (good and poor quality) collected at an industrial mill. Cork samples were cut with the largest dimension in two directions, axial and tangential, and with the load zone in the inner part and the outer part of the plank. The stress-strain curves obtained in bending were similar for the different test specimens and similar to those observed for tensile tests in cork but the mechanical resistance of cork in bending was higher than in tension and lower than in compression. The direction of the internal stress in samples submitted to bending was a highly signiﬁcant factor of variation. The curves showed an initial linear elastic region with a mean Young’s modulus of 14 MPa for the tangential direction and 21 MPa for the axial direction, followed by a region of a gradual cork yielding up to a peak load, and failure at an average stress of 1.2 MPa and a strain of 14%. There was signiﬁcant difference in the bending properties of cork samples obtained from cork planks of different quality classes. Density and porosity were not individually well correlated with the mechanical parameters. It was however possible to model Young’s modulus by combining porosity and density.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Vessel size and number are contributors to define wood density in cork oak</style></title><secondary-title><style face="normal" font="default" size="100%">European Journal of Forest Research</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2011</style></year></dates><volume><style face="normal" font="default" size="100%">130</style></volume><pages><style face="normal" font="default" size="100%">1023-1029</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cork oak (Quercus suber L.) has a dense wood that allows high-quality uses. In the present work, we study the inﬂuence of vessel characteristics, measured through image analysis and optical microscopy, on wood density, measured using X-ray microdensitometry, on 40-year-old trees. Vessel area increases with cambial age (5403–33064 lm 2 ), while wood density decreases (1.229–0.836 g/cm 3 ). The number of vessels is relatively constant at 6 vessels/mm 2 , while vessel proportion in cross-section increases from 3.3% near the pith to 20.5% near the bark. In growth rings closest to the pith, with high wood density and low vessel area, the relationship between the two variables is linear (R 2 = -32.1%, P\0.01) but with increasing tree age and vessel size, the wood density remains rather constant, suggesting that decreases in density might compromise mechanical support of the tree at a stage when the increase in crosssectional area alone might not provide mechanical stability. Other anatomical characteristics not considered in this study, like large xylem rays that increase with cambial age, may be responsible for the constant density</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Costa, Augusta</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author><author><style face="normal" font="default" size="100%">Madeira, Manuel</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Analysis of spatial patterns of oak decline in cork oak woodlands in Mediterranean conditions</style></title><secondary-title><style face="normal" font="default" size="100%">Annals of Forest Science</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Logistic regression</style></keyword><keyword><style  face="normal" font="default" size="100%">Oak decline</style></keyword><keyword><style  face="normal" font="default" size="100%">oak mortality</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus suber L.</style></keyword><keyword><style  face="normal" font="default" size="100%">Remote sensing</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.springerlink.com/openurl.asp?id=doi:10.1051/forest/2009097</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">67</style></volume><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">• Cork oak mortality is a recurrent problem in southwestern Portugal. Despite the perception of increasingly visible damage in oak woodlands on drought-prone sites, the role of the various environmental factors in their decline is not clear. • To describe the spatial patterns of cork oak (Quercus suber L.) mortality, a cork oak mortality index (MI) was determined for each landscape feature (agroforestry system, soil type, slope and aspect) using a GIS approach. To achieve this goal, a logistic regression model was formulated analyzing interactions between landscape attributes and allowing a prediction of cork oak mortality. • Maximum values of MI were found in (i) shrublands and open woodlands with shrub encroachment (MI 6 and 3, respectively), where competition for soil water between tree and understory increases; and (ii) on lower slopes in the rounded hilltops and smooth hillsides or shallow soils where access to groundwater resources during summer drought is diﬃcult. • The model highlighted the importance of the agroforestry systems on cork oak mortality and may be used to identify sensitive areas where mitigation actions should be employed in a scenario of increasing drought severity in these Mediterranean ecosystems.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Teixeira, Rita Teresa</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Suberized Cell Walls of Cork from Cork Oak Differ from Other Species</style></title><secondary-title><style face="normal" font="default" size="100%">Microscopy and Microanalysis</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">cell wall</style></keyword><keyword><style  face="normal" font="default" size="100%">Cork</style></keyword><keyword><style  face="normal" font="default" size="100%">lamellae</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus suber</style></keyword><keyword><style  face="normal" font="default" size="100%">suberin</style></keyword><keyword><style  face="normal" font="default" size="100%">ultrastructure</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010///</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">16</style></volume><pages><style face="normal" font="default" size="100%">569 - 575</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Plants have suberized cells that act as protective interfaces with the environment or between different plant tissues. A lamellar structure of alternating dark and light bands has been found upon transmission electron microscopy (TEM) observation of cork cells and considered a typical feature of the suberized secondary wall. We observed cork cells from periderms of Quercus suber, Quercus cerris, Solanum tuberosum, and Calotropis procera by TEM after uranyl acetate and lead citrate staining. A lamellated structure was observed in S. tuberosum and C. procera but not in Q. suber and Q. cerris where the suberized cell wall showed a predominantly hyaline aspect with only a dark dotted staining. Removal of suberin from Q. suber cells left a thinner secondary wall that lost the translucent aspect. We hypothesize that the species' specific chemical composition of suberin will result in different three-dimensional macromolecular development and in a different spatial location of lignin and other aromatics. A lamellated ultrastructure is therefore not a general feature of suberized cells.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Anjos, Ofélia</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author><author><style face="normal" font="default" size="100%">Rosa, M. Emília</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Tensile properties of cork in axial stress and influence of porosity, density, quality and radial position in the plank</style></title><secondary-title><style face="normal" font="default" size="100%">European Journal of Wood and Wood Products</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cork</style></keyword><keyword><style  face="normal" font="default" size="100%">Density</style></keyword><keyword><style  face="normal" font="default" size="100%">Porosity (voyant)</style></keyword><keyword><style  face="normal" font="default" size="100%">Quality</style></keyword><keyword><style  face="normal" font="default" size="100%">Stress</style></keyword><keyword><style  face="normal" font="default" size="100%">Tensile</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.springerlink.com/index/10.1007/s00107-009-0407-0</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">69</style></volume><pages><style face="normal" font="default" size="100%">85 - 91</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The behaviour of cork under tensile stress in the axial direction was studied for samples taken from cork planks of good (class 1) and poor (class 4) quality grades and at three radial positions within the plank (inner, mid and outer positions). The effect of cork density (ranging from 0.123 to 0.203 g cm−3 ) and porosity (ranging from 2.8 to 9.6% in the tangential surface) on Young’s modulus and fracture stress and strain was studied. The tensile stress-strain curves of cork showed an elastic deformation up to 2% strain with a Young’s modulus of 30.8 MPa, and a fracture stress of 1.05 MPa at a strain of 7.1% for class 1, and Young’s modulus of 26.1 MPa, and a fracture stress of 0.77 MPa at a strain of 5.5% for class 4. Fracture always started at a pore. The quality class and the radial position in the plank were highly signiﬁcant factors of the tensile properties variation with good quality cork in the inner part of the plank showing the highest strength. Density inﬂuenced the elastic behaviour of cork with a highly signiﬁcant correlation of increasing E with density,but not so clearly the fracture stress and strain. The variability of tensile properties with porosity was large and although signiﬁcant, the correlations were lower in spite of a decreasing trend of E with porosity. Fracture depended on the type of defects in cork.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>47</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Costa, Augusta</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author><author><style face="normal" font="default" size="100%">Madeira, Manuel</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Análise Espacial da Mortalidade do Sobreiro em S. Bartolomeu da Serra (Santiago do Cacém)</style></title><secondary-title><style face="normal" font="default" size="100%">Congresso Florestal Nacional, 6º, Ponta Delgada, 2009 - A floresta num mundo globalizado</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">declínio do montado de sobro</style></keyword><keyword><style  face="normal" font="default" size="100%">detecção remota</style></keyword><keyword><style  face="normal" font="default" size="100%">mortalidade do sobreiro</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus suber L.</style></keyword><keyword><style  face="normal" font="default" size="100%">regressão logística</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://hdl.handle.net/10400.5/1706</style></url></web-urls></urls><pages><style face="normal" font="default" size="100%">123 - 129</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Avaliou-se a distribuição espacial da mortalidade do sobreiro (Quercus suber L.) na área da freguesia de S. Bartolomeu da Serra (Santiago do Cacém), integrada numa região em que ela ocorre com elevada incidência, através de técnicas de detecção remota (SIG), e determinou-se a probabilidade de ocorrência de mortalidade através da aplicação de um modelo de regressão logística. Determinou-se um índice de mortalidade e identificaram-se as unidades fisiográficas com maior probabilidade de mortalidade em três sistemas agroflorestais distintos: floresta de sobreiro (florestas densas), montado de sobro tradicional (florestas abertas em sistemas dominantemente agrícolas, com culturas arvenses sob coberto) e incultos (florestas abertas em sistemas dominantemente incultos, com matos sob coberto). A mortalidade do sobreiro é significativamente diferente para os três tipos de sistemas agro-florestais. A mortalidade é influenciada por características físicas da paisagem como o solo, o declive e a exposição. Em solos pouco profundos ou em solos mais compactos, a mortalidade é mais frequente, mostrando a importância do desenvolvimento radicular em profundidade do sobreiro em regiões susceptíveis a extensos períodos de secura.</style></abstract><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;periodical: Congresso Florestal Nacional, 6º, Ponta Delgada, 2009 - A floresta num mundo globalizado</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>3</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Análise Espacial da Mortalidade do Sobreiro em S. Bartolomeu da Serra (Santiago do Cacém)</style></title><secondary-title><style face="normal" font="default" size="100%">Congresso Florestal Nacional, 6º, Ponta Delgada, 2009 - A floresta num mundo globalizado</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year></dates><pages><style face="normal" font="default" size="100%">123-129</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Avaliou-se a distribuição espacial da mortalidade do sobreiro (Quercus suber L.) na área da freguesia de S. Bartolomeu da Serra (Santiago do Cacém), integrada numa região em que ela ocorre com elevada incidência, através de técnicas de detecção remota (SIG), e determinou-se a probabilidade de ocorrência de mortalidade através da aplicação de um modelo de regressão logística. Determinou-se um índice de mortalidade e identificaram-se as unidades fisiográficas com maior probabilidade de mortalidade em três sistemas agroflorestais distintos: floresta de sobreiro (florestas densas), montado de sobro tradicional (florestas abertas em sistemas dominantemente agrícolas, com culturas arvenses sob coberto) e incultos (florestas abertas em sistemas dominantemente incultos, com matos sob coberto). A mortalidade do sobreiro é significativamente diferente para os três tipos de sistemas agro-florestais. A mortalidade é influenciada por características físicas da paisagem como o solo, o declive e a exposição. Em solos pouco profundos ou em solos mais compactos, a mortalidade é mais frequente, mostrando a importância do desenvolvimento radicular em profundidade do sobreiro em regiões susceptíveis a extensos períodos de secura.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Teixeira, Rita Teresa</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ultrastructural Observations Reveal the Presence of Channels between Cork Cells</style></title><secondary-title><style face="normal" font="default" size="100%">MICROSCOPY AND MICROANALYSIS</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Calotropis procera</style></keyword><keyword><style  face="normal" font="default" size="100%">Cork</style></keyword><keyword><style  face="normal" font="default" size="100%">phellogen</style></keyword><keyword><style  face="normal" font="default" size="100%">plasmodesmata</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus suber</style></keyword><keyword><style  face="normal" font="default" size="100%">suberin</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009///</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">15</style></volume><pages><style face="normal" font="default" size="100%">539 - 544</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The ultrastructure of phellem cells of Quercus Silber L. (cork oak) and Calotropis procera (Ait) R. Br. were analyzed using electron transmission microscopy to determine the presence or absence of plasmodesmata (PD). Different types of Q. Silber cork samples were studied: one year shoots; virgin cork (first periderm), reproduction cork (traumatic periderm), and wet cork. The channel structures of PD were found in all the samples crossing adjacent cell walls through the suberin layer of the secondary wait. Calotropis phellem also showed PD crossing the cell walls of adjacent cells but in fewer numbers compared to Q. suber. In one year stems of cork oak, it was possible to follow the physiologically active PD with ribosomic accumulation next to the aperture of the channel seen in the phellogen cells to the completely obstructed channels in the dead cells that characterize the phellem tissue.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;pub-location: 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA&lt;br/&gt;publisher: CAMBRIDGE UNIV PRESS</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Ultrastructural Observations Reveal the Presence of Channels between Cork Cells</style></title><secondary-title><style face="normal" font="default" size="100%">MICROSCOPY AND MICROANALYSIS</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year></dates><publisher><style face="normal" font="default" size="100%">CAMBRIDGE UNIV PRESS</style></publisher><pub-location><style face="normal" font="default" size="100%">32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA</style></pub-location><volume><style face="normal" font="default" size="100%">15</style></volume><pages><style face="normal" font="default" size="100%">539-544</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The ultrastructure of phellem cells of Quercus Silber L. (cork oak) and Calotropis procera (Ait) R. Br. were analyzed using electron transmission microscopy to determine the presence or absence of plasmodesmata (PD). Different types of Q. Silber cork samples were studied: one year shoots; virgin cork (first periderm), reproduction cork (traumatic periderm), and wet cork. The channel structures of PD were found in all the samples crossing adjacent cell walls through the suberin layer of the secondary wait. Calotropis phellem also showed PD crossing the cell walls of adjacent cells but in fewer numbers compared to Q. suber. In one year stems of cork oak, it was possible to follow the physiologically active PD with ribosomic accumulation next to the aperture of the channel seen in the phellogen cells to the completely obstructed channels in the dead cells that characterize the phellem tissue.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Effect of quality, porosity and density on the compression properties of cork</style></title><secondary-title><style face="normal" font="default" size="100%">Holz als Roh- und Werkstoff</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year></dates><volume><style face="normal" font="default" size="100%">66</style></volume><pages><style face="normal" font="default" size="100%">295-301</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The compression properties of cork were studied on samples obtained from cork planks of two commercial quality classes (good and poor quality), with densities ranging from 0.12–0.20g cm−3 and porosities from 0.5 to 22.0%. The stress-strain curves were characterized by an elastic region up to approximately 5% strain, followed by a large plateau up to 60% strain caused by the progressive buckling of cell walls, and a steep stress increase for higher strains corresponding to cell collapse. The direction of compression was a highly signiﬁcant factor of variation, with cork showing higher strength for the radial compression. Density inﬂuenced compression and cork samples with higher density showed overall larger resistance to compression in the three directions. In the elastic region, an exponential model of Young’s modulus in function of cork density could be adjusted. The effect of porosity on compression was small and the stress-strain curves were similar regardless of the porosity of the samples, although there was a trend toward an overall increase of stress with porosity for higher strains. Porosity was characterised by a high variability in the anatomical features of the lenticular ﬁlling material and the presence of collapsed and thick walled ligniﬁed cells. The inclusion of a porosity parameter for the modelling of the elastic modulus did not improve the prediction obtained with densitybased models. There was no signiﬁcant difference in the compression properties of cork samples obtained from cork planks of good and poor quality classes.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Anjos, Ofélia</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author><author><style face="normal" font="default" size="100%">Rosa, M. Emília</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effect of quality, porosity and density on the compression properties of cork</style></title><secondary-title><style face="normal" font="default" size="100%">Holz als Roh- und Werkstoff</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Compression</style></keyword><keyword><style  face="normal" font="default" size="100%">Cork</style></keyword><keyword><style  face="normal" font="default" size="100%">Density</style></keyword><keyword><style  face="normal" font="default" size="100%">Porosity</style></keyword><keyword><style  face="normal" font="default" size="100%">Quality</style></keyword><keyword><style  face="normal" font="default" size="100%">stress (voyant)</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.springerlink.com/index/10.1007/s00107-008-0248-2</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">66</style></volume><pages><style face="normal" font="default" size="100%">295 - 301</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The compression properties of cork were studied on samples obtained from cork planks of two commercial quality classes (good and poor quality), with densities ranging from 0.12–0.20g cm−3 and porosities from 0.5 to 22.0%. The stress-strain curves were characterized by an elastic region up to approximately 5% strain, followed by a large plateau up to 60% strain caused by the progressive buckling of cell walls, and a steep stress increase for higher strains corresponding to cell collapse. The direction of compression was a highly signiﬁcant factor of variation, with cork showing higher strength for the radial compression. Density inﬂuenced compression and cork samples with higher density showed overall larger resistance to compression in the three directions. In the elastic region, an exponential model of Young’s modulus in function of cork density could be adjusted. The effect of porosity on compression was small and the stress-strain curves were similar regardless of the porosity of the samples, although there was a trend toward an overall increase of stress with porosity for higher strains. Porosity was characterised by a high variability in the anatomical features of the lenticular ﬁlling material and the presence of collapsed and thick walled ligniﬁed cells. The inclusion of a porosity parameter for the modelling of the elastic modulus did not improve the prediction obtained with densitybased models. There was no signiﬁcant difference in the compression properties of cork samples obtained from cork planks of good and poor quality classes.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Within-tree and between-tree variation of wood density components in cork oak trees in two sites in Portugal</style></title><secondary-title><style face="normal" font="default" size="100%">Forestry</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year></dates><volume><style face="normal" font="default" size="100%">81</style></volume><pages><style face="normal" font="default" size="100%">465-473</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The axial and radial variation of wood density was studied using microdensitometry in cork oaks (Quercus suber) in two sites in Portugal. The observations were made in mature trees under cork production and in juvenile trees before the first cork extraction, at three height levels (stem base, 1.3 m and before stem bifurcation). The cork oak wood revealed a very high mean density (0.884–1.068 g cm−3). Differences between earlywood and latewood were small (0.866 and 1.061 g cm−3, respectively). Latewood corresponded on average to 61 per cent of the total. The variation of density between trees was statistically highly significant, but no differences were found between the two sites. The within-tree axial variation was negligible but the radial direction within a cross-section was one of the main origins of variation of the density components (18 per cent of the total variation). The density decreased from pith to cambium and this radial variation corresponded to 19–24 per cent of the total variation of wood density. Overall, the magnitude of density variations between and within cork oaks was small and an advantageous factor for their use for quality wood products.</style></abstract><notes><style face="normal" font="default" size="100%">10.1093/forestry/cpn012</style></notes><research-notes><style face="normal" font="default" size="100%">10.1093/forestry/cpn012</style></research-notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Cork oak (Quercus suber L.) wood growth and vessel characteristics variations in relation to climate and cork harvesting</style></title><secondary-title><style face="normal" font="default" size="100%">European Journal of Forest Research</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year></dates><volume><style face="normal" font="default" size="100%">127</style></volume><pages><style face="normal" font="default" size="100%">33-41</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Variations in tree ring growth of Quercus suber L. were analysed using dendrochronological techniques on cork oak discs from trees harvested in the cork producing region of Alentejo, Portugal. A tree-ring chronology containing a strong common signal and covering the period from 1970 to 1995 was build for ca. 30-year-old cork oaks never submitted to cork harvesting using 14 trees that crossdated satisfactorily out of 30 sampled trees. The tree ring indices correlated positively with September temperature (r = 0.48, P &lt; 0.05) and very strongly with precipitation totals from previous October until current February (r = 0.82, P &lt; 0.001) showing that the water stored in the soil during the autumn and winter months prior to the growing season has a primordial effect on the growth of the given season. The effects of cork harvesting were analysed by comparing mean ring width, mean annual vessel area, vessel density (nvessels/mm 2 ), and vessel coverage (percentage of transverse surface occupied by vessels) between three mature cork oak trees and three young trees, for the period from 1987 to 1996, corresponding to the growth between two consecutive cork removals in the case of mature trees. In 1988, 1989 and 1996 (corresponding to the ﬁrst and second years after cork removal, and 1996 to a year of cork removal), the ratios between ring widths of young versus mature trees was twice that for the rest of the period. However, an effect of cork removal indicated by eventual alterations in vessel size and distribution in the wood rings corresponding to the years 1988, 1989 and 1996 in the mature cork oaks was not observed.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Costa, Augusta</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Influence of vision systems, black and white, colored and visual digitalization, in natural cork stopper quality estimation</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of the Science of Food and Agriculture</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">canonical discriminant analysis</style></keyword><keyword><style  face="normal" font="default" size="100%">cork pores</style></keyword><keyword><style  face="normal" font="default" size="100%">image analysis</style></keyword><keyword><style  face="normal" font="default" size="100%">natural cork stopper</style></keyword><keyword><style  face="normal" font="default" size="100%">quality classification</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://dx.doi.org/10.1002/jsfa.2947</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">87</style></volume><pages><style face="normal" font="default" size="100%">2222 - 2228</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Quality classification of wine natural cork stoppers is related to presence of discontinuities in the cork tissue. Automated image analysis of stoppers based on black and white cameras is used industrially for commercial classification but recently color has been introduced in image processing. This paper compares the performance of three image vision systems regarding classification accuracy of cork stoppers of good, medium and inferior quality: black and white, three-band RGB color and manual detection by digitalization in color image. A canonical discriminant analysis approach was used to compare the discriminating power between cork stopper quality in each vision system. Good discriminant results were obtained with the area of pores expressed either in total or as ratio, mean or maximum value. The use of color slightly enlarges the range of cork inspection systems and automated systems have a similar accuracy of classification to visual inspection. Copyright © 2007 Society of Chemical Industry</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;publisher: John Wiley &amp; Sons, Ltd.</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Influence of vision systems, black and white, colored and visual digitalization, in natural cork stopper quality estimation</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of the Science of Food and Agriculture</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year></dates><publisher><style face="normal" font="default" size="100%">John Wiley &amp; Sons, Ltd.</style></publisher><volume><style face="normal" font="default" size="100%">87</style></volume><pages><style face="normal" font="default" size="100%">2222-2228</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Quality classification of wine natural cork stoppers is related to presence of discontinuities in the cork tissue. Automated image analysis of stoppers based on black and white cameras is used industrially for commercial classification but recently color has been introduced in image processing. This paper compares the performance of three image vision systems regarding classification accuracy of cork stoppers of good, medium and inferior quality: black and white, three-band RGB color and manual detection by digitalization in color image. A canonical discriminant analysis approach was used to compare the discriminating power between cork stopper quality in each vision system. Good discriminant results were obtained with the area of pores expressed either in total or as ratio, mean or maximum value. The use of color slightly enlarges the range of cork inspection systems and automated systems have a similar accuracy of classification to visual inspection. Copyright © 2007 Society of Chemical Industry</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Radial variation of vessel size and distribution in cork oak wood (Quercus suber L.)</style></title><secondary-title><style face="normal" font="default" size="100%">Wood Science and Technology</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year></dates><volume><style face="normal" font="default" size="100%">41</style></volume><pages><style face="normal" font="default" size="100%">339-350</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Quercus suber L. is an important species producing cork whose wood characteristics have not been investigated a lot. Cork oak wood vessels are a striking feature and the most abundant wood tissue largely inﬂuencing density and permeability. Vessel size and distribution were studied in approximately 40 year-old and never debarked cork oaks by continuously measuring along the radial direction in the transverse section of wood discs taken at 1.3 m of height using image analysis techniques. The vessel size increases with age from 7660 ± 2286 to 21136 ± 6119 lm 2 , the conductive area from 5.4 ± 2.2 to 11.6 ± 3.9%, and the vessel density remains approximately constant between 5.2 ± 1.5 and 7.3 ± 3.5 vessels/mm 2 . In comparison with ring-porous and some evergreen oaks, cork oaks show a similar conductive area but smaller vessels. Vessel architecture is known to play an important role on oaks tolerance to hydric stress, and these cork oak trees were growing under very harsh edaphoclimatic conditions, not tolerated by other oaks. The well-developed and deep root system allowing access to constant water supply may contribute to the cork oak’s relatively high conductive area.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Decision rules for computer-vision quality classification of wine natural cork stoppers</style></title><secondary-title><style face="normal" font="default" size="100%">AMERICAN JOURNAL OF ENOLOGY AND VITICULTURE</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year></dates><publisher><style face="normal" font="default" size="100%">AMER SOC ENOLOGY VITICULTURE</style></publisher><pub-location><style face="normal" font="default" size="100%">PO BOX 1855, DAVIS, CA 95617-1855 USA</style></pub-location><volume><style face="normal" font="default" size="100%">57</style></volume><pages><style face="normal" font="default" size="100%">210-219</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Image-analysis techniques were applied to the surface of wine cork stoppers (tops and bodies) of the standard seven commercial quality classes to characterize their porosity. Canonical discriminant analysis (CDA) and stepwise discriminant analysis (SDA) were used to differentiate quality class and to identify the best features to select these classes. The accuracy of classification using CDA functions was on average greater than 50% for the seven commercial classes and was greater than 67% for a simplified three-grade classification. Based on the independent variables of the first CDA function determined by the stepwise method, a set of features was selected for use in decision rules for cork stopper classification: porosity coefficient and maximum pore dimensions (length and area) for bodies and porosity coefficient and number of pores for tops. Threshold limits for each feature were established for each quality class and a classification algorithm was applied. Results showed an overall match in class yield of 86% and better class homogeneity and separation. These are proposed as a foundation for future standardization of cork stopper classification based on image analysis and computerized vision systems selection of quantified features to ensure uniformity and transparency in trade while maintaining the overall economical feasibility in industrial processing.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Costa, Augusta</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Decision rules for computer-vision quality classification of wine natural cork stoppers</style></title><secondary-title><style face="normal" font="default" size="100%">AMERICAN JOURNAL OF ENOLOGY AND VITICULTURE</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">canonical discriminant</style></keyword><keyword><style  face="normal" font="default" size="100%">quality classes</style></keyword><keyword><style  face="normal" font="default" size="100%">wine cork stoppers</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006///</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">57</style></volume><pages><style face="normal" font="default" size="100%">210 - 219</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Image-analysis techniques were applied to the surface of wine cork stoppers (tops and bodies) of the standard seven commercial quality classes to characterize their porosity. Canonical discriminant analysis (CDA) and stepwise discriminant analysis (SDA) were used to differentiate quality class and to identify the best features to select these classes. The accuracy of classification using CDA functions was on average greater than 50% for the seven commercial classes and was greater than 67% for a simplified three-grade classification. Based on the independent variables of the first CDA function determined by the stepwise method, a set of features was selected for use in decision rules for cork stopper classification: porosity coefficient and maximum pore dimensions (length and area) for bodies and porosity coefficient and number of pores for tops. Threshold limits for each feature were established for each quality class and a classification algorithm was applied. Results showed an overall match in class yield of 86% and better class homogeneity and separation. These are proposed as a foundation for future standardization of cork stopper classification based on image analysis and computerized vision systems selection of quantified features to ensure uniformity and transparency in trade while maintaining the overall economical feasibility in industrial processing.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;pub-location: PO BOX 1855, DAVIS, CA 95617-1855 USA&lt;br/&gt;publisher: AMER SOC ENOLOGY VITICULTURE</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Within and between-tree variation in the biometry of wood rays and fibres in cork oak (Quercus suber_L.)</style></title><secondary-title><style face="normal" font="default" size="100%">Wood Science and Technology</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year></dates><volume><style face="normal" font="default" size="100%">40</style></volume><pages><style face="normal" font="default" size="100%">585-597</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The variability of ﬁbre and ray dimensions was studied at three radial positions (10, 50 and 90% of radius) in 5 cork oaks (Quercus suber L.) approximately 40 years old. Uniseriate ray height and cell number as well as multiseriate ray height and width were measured in tangential sections. Fibre length, width and wall thickness were measured after maceration. The most striking features of cork oak wood were the large multiseriate rays and the frequent homocellular uniseriate rays. On average multiseriate rays were 5.16 mm high and 0.48 mm wide, and uniseriate rays contained 11 cells and were 227 lm high. Neighbour rays presented large dimensional diﬀerences but there was no radial variation and there were very small between-tree diﬀerences. The radial maintenance of high and wide rays was discussed as a means to improve water shortage in response to water stress. Fibre dimensions increased radially but diﬀered little between trees: on average, 960–1,220 lm length, 18.40–21.49 lm width and 6.66–8.07 lm wall thickness. The ray pattern showed enough variation for visual appreciation while ensuring within and between-tree uniformity. The presence of rays has to be taken into consideration for designing wood drying programs.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>3</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">cork oak wood a hard material to sample and to measure</style></title><secondary-title><style face="normal" font="default" size="100%">Suberwood2005: New challenges for integration of cork oak forests and products, Scientific and Technical Conference, Huelva, Spain, 20, 21 and 22 October 2005.</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2005</style></year></dates><publisher><style face="normal" font="default" size="100%">Universidad de Huelva</style></publisher><pub-location><style face="normal" font="default" size="100%">Huelva</style></pub-location><pages><style face="normal" font="default" size="100%">456</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Different studies within the Suberwood project required measurements of wood growth in cork oak trees (Quercus suber L.), including tree ring analysis, as a basis to analyse the influence on tree growth of stress effects, namely those deriving from climatic conditions (i.e. water deficit) or from the cork extraction. The research partners have experienced serious difficulties in these tasks and some examples are presented and discussed. The first difficulty regards sampling because cork oak harvesting is forbidden in Portugal and advantage has to be taken from legally authorised tree fellings. The available material therefore consists mainly in thinning material (young trees), dead or diseased trees, and trees with damaged stems due to improper cork harvesting, which are useless for such studies. In most cases the information concerning the stand management is lacking, namely regarding the time of cork extraction and of other silvicultural operations (i.e. pruning). Therefore the experimental design regarding treatments and repetitions often cannot follow the conventional statistical guidelines. The cork oak wood also has anatomical and structural features that bring considerable complexity for ring definition. The wood has a semi-ring porosity with poor growth ring definition and it is very difficult, and frequently impossible, to accurately identify growth rings and to link measurements to a certain year. Additionally cork extraction disturbs wood growth and anatomy. Different observation approaches were tested: overall microscopical observations, continuous radial measurement of vessel dimensions and density, continuous radial microdensitometric profiles, cambial wounding. The use of non-destructive samples (i.e. cores or small wood samples) adds to the uncertainty encountered. Stem discs offer a better observation but differences among different radii are often very large.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>3</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Modelos de reconstrução do tronco e programas de simulação . Ferramentas para avaliar o potencial de produção de madeira em sobreiros jovens .</style></title><secondary-title><style face="normal" font="default" size="100%">Congresso Florestal Nacional, 5º, Viseu, 2005</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2005</style></year></dates><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">O sobreiro (Quercus suber L.) é actualmente valorizado como produtor de cortiça, embora no passado a madeira de sobreiro tenha já sido o produto desejado. A disponibilidade da madeira de sobreiro para serração encontra-se limitada ao material proveniente de desbastes ou de abates autorizados. Este estudo teve como objectivo avaliar o potencial desta espécie para a produção de peças sólidas de madeira através da aplicação de técnicas de reconstrução tridimensionais do tronco e simulação de serração. Utilizaram-se os programas de reconstrução do tronco e de simulação de corte WoodCIM®, desenvolvidos no VTT (Technical Research Centre of Finland), que permitiram prever rendimentos da produção em serração. Pretendeu-se contribuir para o aumento do conhecimento do sobreiro como espécie madeireira e do seu potencial para o fabrico de peças de qualidade elevada. Utilizaram-se três sobreiros jovens, escolhidos aleatoriamente num povoamento em desbaste. Os troncos foram cortados em serração em tábuas com 22 mm de espessura. Nestas foi aplicada uma técnica de varrimento visual (scan) e através de análise de imagem (programa PuuPilot) e utilizando um software de reconstrução matemática foi possível desenvolver modelos bi e tridimensionais próximos da realidade, permitindo uma visualização do tronco, entrecasco e cortiça. Neste estudo analisou-se a produção de peças para painéis e soalho. As árvores foram virtualmente serradas em toros de 500 e 1000 mm de comprimento. Os rendimentos variaram entre 26,6% e 35,4% para toros de 0,5 m, e 28,75 e 34,0% para toros de 1,0 m. O melhor rendimento foi obtido para a produçao de parquet, utilizando toros de 0,5 m.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>3</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">SEASONAL PATTERN OF PHYSIOLOGICAL STATE IN A CORK OAK (QUERCUS SUBER L.) STAND IN HUELVA (SPAIN)</style></title><secondary-title><style face="normal" font="default" size="100%">Suberwood2005: New challenges for integration of cork oak forests and products, Scientific and Technical Conference, Huelva, Spain, 20, 21 and 22 October 2005.</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2005</style></year></dates><publisher><style face="normal" font="default" size="100%">Universidad de Huelva</style></publisher><pub-location><style face="normal" font="default" size="100%">Huelva</style></pub-location><pages><style face="normal" font="default" size="100%">456</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The seasonal pattern of the physiological state of Quercus suber is determined by different ecological factors, and it affects to the growth of the species. The main objective of this study is to know the seasonal pattern of water potential, photosynthesis and fluorescence in four Quercus suber L. trees and to relate these values with ecological factors during two years. In this time there were three critical periods, the first one the end of the dry period where the water potential descends to values less than -3MPa and the photosynthesis to 0.781 µmol CO2m-2 s-1Quercus suber, physiology, water potential, photosynthesis, fluorescence. . The second critical period is located in period of change of the leaf, between the months of March and May. The third critical period occurred due to the freezes and drought of the year 2005, that produced strong damages in the PSII.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>47</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">GONZÁLEZ-PÉREZ, ARANTZAZU</style></author><author><style face="normal" font="default" size="100%">VÁZQUEZ-PIQUÉ, JAVIER</style></author><author><style face="normal" font="default" size="100%">TAPIAS, RAÚL</style></author><author><style face="normal" font="default" size="100%">FERNÁNDEZ, MANUEL</style></author></authors><secondary-authors><author><style face="normal" font="default" size="100%">VÁZQUEZ-PIQUÉ, JAVIER</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author><author><style face="normal" font="default" size="100%">GONZÁLEZ-PÉREZ, ARANTZAZU</style></author></secondary-authors></contributors><titles><title><style face="normal" font="default" size="100%">SEASONAL PATTERN OF PHYSIOLOGICAL STATE IN A CORK OAK (QUERCUS SUBER L.) STAND IN HUELVA (SPAIN)</style></title><secondary-title><style face="normal" font="default" size="100%">Suberwood2005: New challenges for integration of cork oak forests and products, Scientific and Technical Conference, Huelva, Spain, 20, 21 and 22 October 2005.</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">fluorescenc</style></keyword><keyword><style  face="normal" font="default" size="100%">photosynthesis</style></keyword><keyword><style  face="normal" font="default" size="100%">physiology</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus suber</style></keyword><keyword><style  face="normal" font="default" size="100%">water potential</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2005</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2005///</style></date></pub-dates></dates><publisher><style face="normal" font="default" size="100%">Universidad de Huelva</style></publisher><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The seasonal pattern of the physiological state of Quercus suber is determined by different ecological factors, and it affects to the growth of the species. The main objective of this study is to know the seasonal pattern of water potential, photosynthesis and fluorescence in four Quercus suber L. trees and to relate these values with ecological factors during two years. In this time there were three critical periods, the first one the end of the dry period where the water potential descends to values less than -3MPa and the photosynthesis to 0.781 µmol CO2m-2 s-1Quercus suber, physiology, water potential, photosynthesis, fluorescence. . The second critical period is located in period of change of the leaf, between the months of March and May. The third critical period occurred due to the freezes and drought of the year 2005, that produced strong damages in the PSII.</style></abstract><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;periodical: Suberwood2005: New challenges for integration of cork oak forests and products, Scientific and Technical Conference, Huelva, Spain, 20, 21 and 22 October 2005.&lt;br/&gt;pub-location: Huelva</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Caracterização e Análise de Rendimento da Operação de Traçamento na Preparação de Pranchas de Cortiça para a Produção de Rolhas</style></title><secondary-title><style face="normal" font="default" size="100%">Silva Lusitana</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2004</style></year></dates><publisher><style face="normal" font="default" size="100%">scielopt</style></publisher><volume><style face="normal" font="default" size="100%">12</style></volume><pages><style face="normal" font="default" size="100%">51-66</style></pages><isbn><style face="normal" font="default" size="100%">0870-6352 UL - http://www.scielo.gpeari.mctes.pt/scielo.php?script=sci_arttext&amp;pid=S0870-63522004000200005&amp;nrm=iso</style></isbn><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The industrial processing of natural cork stoppers, the most profitable cork product, begins with the preparation of the cork planks. The raw cork planks are boiled in water and then manually cut by expert operators into smaller planks of homogeneous thickness and quality. This operation originates the first cork wastes in the industrial process. The cutting of the cork planks was studied with a random sampling of raw cork planks taken from one industrial unit after boiling, for which a virtual cutting was made following the markings done by skilled operators. The dimension and shape of the cork planks were analyzed as well as the potential maximum number of cork stoppers to be produced. The area, length and width of the raw cork planks are related with the shape of the tree stem and branches and with the cork stripping techniques, while the dimensions of the prepared cork planks are related to the specificities of the manual handling in the following operations in the industrial flow. On average, the cutting decreased the cork plank area to half. The wastes consisting of small pieces represented 5% of the initial raw cork. The analysis of the maximum potential yield of cork stoppers showed that the regions of the raw cork planks that do not allow the cutting of cork strips for the punching out of stoppers or their excess length represent a waste residue amounting to 17% of the cork plank area. The potential maximum number of cork stoppers depended directly on the plank area but the proportion of waste showed a decreasing trend with the increase of the plank area. In order to maximize the yield in the production of cork stoppers, raw cork planks with large dimensions should be used, taking into account the probable need for automation in the industrial cutting of cork strips.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">The periderm development in Quercus suber</style></title><secondary-title><style face="normal" font="default" size="100%">IAWA Journal</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2004</style></year></dates><volume><style face="normal" font="default" size="100%">25</style></volume><pages><style face="normal" font="default" size="100%">325-335</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In the cork oak (Quercus suber L.), the phellogen differentiates during the first year of growth in the cell layer immediately under the epidermis and divides to form 3–6 suberized phellem cells. Division of the phellogen only occurs after suberization of the previous divided cell. During the first four years of growth, the phellem cells have tannin-filled lumens and it is only in the 5th to 7th years that they acquire the characteristics of ʻadultʼ cork cells with empty lumens and thin suberized walls. The len- ticels are formed by the lenticular phellogen, which differentiates under the stomata and has a high meristematic activity. In this region, the cells are unsuberized, with a loose arrangement and intercellular voids, consti- tuting the filling or complementary tissue. After three years, the lenticels appear as small protuberances that soon become conspicuous. Inclusions of sclerenchymatous nodules and isolated sclereids occur occasionally mostly in the vicinity of, or in, the lenticels.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Influence of climate on the seasonality of radial growth of cork oak during a cork production cycle</style></title><secondary-title><style face="normal" font="default" size="100%">Ann. For. Sci.</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2002</style></year></dates><volume><style face="normal" font="default" size="100%">59</style></volume><pages><style face="normal" font="default" size="100%">429-437</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The radial growth of mature cork oaks (Quercus suber L.) was studied during a 9-year production cycle using monthly dendrometer measurements and cork ring widths. The mean tree radial increase was 5.1 mm yr -1 and the cork increment accounting for 3.8 mm yr -1. The radial growth curves for cork, wood and stem were very similar, showing a decreasing trend along the production cycle. Cork increment was always the largest fraction of tree growth (on average 74%) and showed less inter-annual variations as compared to wood. Tree radial growth presented a clear within-the-year seasonal pattern, extending from March to October, with a maximum in June-July. The overall pattern of monthly growth distribution was similar among the years of the production cycle, but some inter-annual variations occurred with 1-2 month shifts or monthly growth rate decreases, related to climatic factors. Early spring growth was enhanced by winter rain, autumn growth by high summer rain and June increments by high temperatures during this month.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Costa, Augusta</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author><author><style face="normal" font="default" size="100%">Oliveira, Ângelo</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Influence of climate on the seasonality of radial growth of cork oak during a cork production cycle</style></title><secondary-title><style face="normal" font="default" size="100%">Ann. For. Sci.</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">climatic fluctuations</style></keyword><keyword><style  face="normal" font="default" size="100%">cork growth</style></keyword><keyword><style  face="normal" font="default" size="100%">Cork oak</style></keyword><keyword><style  face="normal" font="default" size="100%">dendroclimatology</style></keyword><keyword><style  face="normal" font="default" size="100%">diameter growth</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2002</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2002///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://dx.doi.org/10.1051/forest:2002017</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">59</style></volume><pages><style face="normal" font="default" size="100%">429 - 437</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The radial growth of mature cork oaks (Quercus suber L.) was studied during a 9-year production cycle using monthly dendrometer measurements and cork ring widths. The mean tree radial increase was 5.1 mm yr -1 and the cork increment accounting for 3.8 mm yr -1. The radial growth curves for cork, wood and stem were very similar, showing a decreasing trend along the production cycle. Cork increment was always the largest fraction of tree growth (on average 74%) and showed less inter-annual variations as compared to wood. Tree radial growth presented a clear within-the-year seasonal pattern, extending from March to October, with a maximum in June-July. The overall pattern of monthly growth distribution was similar among the years of the production cycle, but some inter-annual variations occurred with 1-2 month shifts or monthly growth rate decreases, related to climatic factors. Early spring growth was enhanced by winter rain, autumn growth by high summer rain and June increments by high temperatures during this month.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Caractérisation de la croissance et de la qualité du liège dans une région de production</style></title><secondary-title><style face="normal" font="default" size="100%">Ann. For. Sci.</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2000</style></year></dates><volume><style face="normal" font="default" size="100%">57</style></volume><pages><style face="normal" font="default" size="100%">187-193</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cork growth and quality were characterised in 5 cork oak stands within the production area of the Sado basin (Alcácer do Sal, Portugal) based on a field sampling on 40 trees/stand. Cork thickness was on average 33.8 mm, with 75% of the samples in the commercial classes above 27 mm suitable for production of stoppers. Porosity measured by image analysis was 4.6% on average. Between tree and between stand variability of cork quality was large. The annual average cork growth for a production cycle with 8 complete growth years was 4.1 mm, being highest during the years following cork extraction and decreasing during the cycle. For this region, a production cycle of 9 years is adequate for raw-material industrial requirements. The results show the importance of between tree variability in growth and especially in quality.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ferreira, Alexandra</style></author><author><style face="normal" font="default" size="100%">Lopes, Fernando</style></author><author><style face="normal" font="default" size="100%">Pereira, Helena</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Caractérisation de la croissance et de la qualité du liège dans une région de production</style></title><secondary-title><style face="normal" font="default" size="100%">Ann. For. Sci.</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cork</style></keyword><keyword><style  face="normal" font="default" size="100%">Growth</style></keyword><keyword><style  face="normal" font="default" size="100%">Porosity</style></keyword><keyword><style  face="normal" font="default" size="100%">Quality</style></keyword><keyword><style  face="normal" font="default" size="100%">variability</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2000</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2000///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://dx.doi.org/10.1051/forest:2000169</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">57</style></volume><pages><style face="normal" font="default" size="100%">187 - 193</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cork growth and quality were characterised in 5 cork oak stands within the production area of the Sado basin (Alcácer do Sal, Portugal) based on a field sampling on 40 trees/stand. Cork thickness was on average 33.8 mm, with 75% of the samples in the commercial classes above 27 mm suitable for production of stoppers. Porosity measured by image analysis was 4.6% on average. Between tree and between stand variability of cork quality was large. The annual average cork growth for a production cycle with 8 complete growth years was 4.1 mm, being highest during the years following cork extraction and decreasing during the cycle. For this region, a production cycle of 9 years is adequate for raw-material industrial requirements. The results show the importance of between tree variability in growth and especially in quality.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Methanolysis of bark suberins: analysis of glycerol and acid monomers</style></title><secondary-title><style face="normal" font="default" size="100%">Phytochemical Analysis</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2000</style></year></dates><volume><style face="normal" font="default" size="100%">11</style></volume><pages><style face="normal" font="default" size="100%">45-51</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The depolymerization and subsequent analysis of cork suberins from the outer barks of Pseudotsuga menziesii and Quercus suber was performed using a simpliﬁed methanolysis procedure. The amount of sodium methoxide catalyst was maintained at 20–30 mM and the methanolysis mixture was submitted to trimethylsilyl derivatisation and used directly for gas chromatographic analysis, allowing simultaneous quantiﬁcation of glycerol and long-chain monomers. Response factors for glycerol, ferulic acid and one saturated homologue representing each of the suberinic families (i.e. the 1-alkanols, 1-alkanoic acids, vhydroxyacids and a,v-diacids) were determined. Effective depolymerization of suberin was checked using the infrared specta of the residues after methanolysis. Glycerol is a major constituent of the suberins from P. menziesii (26% of total) and from Q. suber (14%). In both suberins, a,v-diacids are dominant, i.e. 54% of the long-chain monomers in P. menziesii (mostly saturated C16-C22 homologues and the C18 unsaturated diacid), and 53% in Q. suber (mostly the C18 unsaturated diacid and mid-chain oxygenated (epoxide and vic-diol) derivatives). In P. menziesii epoxyacids are absent. The importance of glycerol and a,v-diacids as suberin monomers supports a polymeric structure based on their successive esteriﬁcation.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Feruloyl Esters of ω-Hydroxyacids in Cork Suberin</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Wood Chemistry and Technology</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">1998</style></year></dates><publisher><style face="normal" font="default" size="100%">Taylor &amp; Francis</style></publisher><volume><style face="normal" font="default" size="100%">18</style></volume><pages><style face="normal" font="default" size="100%">207-217</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Feruloyl esters of ?-hydroxyacids were found in the alcoholysis products of suberin from Quercus suber cork. Their identification was made from mass spectra and by comparison with synthetic model compounds. The co-hydroxyls of suberinic hydroxyacids are thought to be the ester-bonding points between suberin aliphatics and associated aromatics.</style></abstract><notes><style face="normal" font="default" size="100%">doi: 10.1080/02773819809349577</style></notes><research-notes><style face="normal" font="default" size="100%">doi: 10.1080/02773819809349577</style></research-notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Cork Suberin: A Glyceryl Based Polyester</style></title><secondary-title><style face="normal" font="default" size="100%">Holzforschung - International Journal of the Biology, Chemistry, Physics and Technology of Wood</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">1997</style></year></dates><volume><style face="normal" font="default" size="100%">51</style></volume><pages><style face="normal" font="default" size="100%">225-234</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Total depolymerization of cork from the cork oak (Quercus suber L.) by using a sodium methoxide catalysed methanolysis solubilized 53.2 % of the material, including 5.2 % of glycerol, 48,0 % of suberinic fatty acids and alcohols and minor amounts of ferulic acid. A very mild depolymerization using calcium oxide treated methanol, which solubilized only 2.0% of the cork material was studied by GC-MS. In the solubilized material, the total amount of aliphatic acids was 43.8 % (including alkanoic acids 4.0%. ω-hydroxyacids 13.2% and α,ω-diacids 26.6%), of 1-alkanols 2.1 % and of monoacylglycenols 32.1%. It was possible to identify 1-monoacylglycerols and 2-monoacylglycerols of alkanoic acids (1,2%), ω-hydroxyacids (3.7 %) and α,ω-diacids (22.8 %). It is proposed that suberin is a glyceryl based polymer and that its insoluble character is given, at least in part, by the cross-linking of dicarboxylic fatty acids with glycerol. The term suberin should be used for this aliphatic polyester component of the cell wall.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>3</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Suberina: o polímero responsá vel pelas propriedades da cortiça</style></title><secondary-title><style face="normal" font="default" size="100%">II Congreso Forestal Español</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">1997</style></year></dates><pub-location><style face="normal" font="default" size="100%">Pamplona</style></pub-location><pages><style face="normal" font="default" size="100%">225-228</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The macromolecular structure of suberin, the biopolymer mainly responsable for cork properties, is dicussed. The link of the suberinic aliphatic acids to glycerol is presented, supporting the hypothesis that suberin is a glyceridic polyester. The linkage of this aliphatic part, through ferulic acid, to the aromatic part, and the similarities of the later to lignin, are discussed. K.W.:</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>47</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Variaçáo da porosidade da cortiça ao longo do tronco dosobreiro</style></title><secondary-title><style face="normal" font="default" size="100%">II Congreso Forestal Español</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">1997</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1997///</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">253 - 258</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The within tree variation of cork quality has practical relevance when considering the methodology for estimating the quality of production using a field sampling. Samples are usually taken at breast height and an indication how quality at this level might relate to the overall average quality would help to improve estimates for the overall stand cork quality. The porosity of cork was analysed for whole stems. A total of 12 trees were evaluated, from six sites (Mora, Palma, Porto Alto, Grandola, Azaruja and Chamusca). The porosity was measured using image analysis techniques in tangential sections and in transverse sections. The cork for the different trees observed had different average porosities, ranging from 2.7% to 14.5% in the transverse section at b.h .. Within tree variatíon of cork porosity was found, with a average pattern of decreasing porosity within tree height. However a umque pattern of variation could not be established.</style></abstract><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;periodical: II Congreso Forestal Español&lt;br/&gt;pub-location: Pamplona</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>3</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Variaçáo da porosidade da cortiça ao longo do tronco dosobreiro</style></title><secondary-title><style face="normal" font="default" size="100%">II Congreso Forestal Español</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">1997</style></year></dates><pub-location><style face="normal" font="default" size="100%">Pamplona</style></pub-location><pages><style face="normal" font="default" size="100%">253-258</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The within tree variation of cork quality has practical relevance when considering the methodology for estimating the quality of production using a field sampling. Samples are usually taken at breast height and an indication how quality at this level might relate to the overall average quality would help to improve estimates for the overall stand cork quality. The porosity of cork was analysed for whole stems. A total of 12 trees were evaluated, from six sites (Mora, Palma, Porto Alto, Grandola, Azaruja and Chamusca). The porosity was measured using image analysis techniques in tangential sections and in transverse sections. The cork for the different trees observed had different average porosities, ranging from 2.7% to 14.5% in the transverse section at b.h .. Within tree variatíon of cork porosity was found, with a average pattern of decreasing porosity within tree height. However a umque pattern of variation could not be established.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>7</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">High - pressure extraction of cork with CO2 and 1,4-dioxane</style></title><secondary-title><style face="normal" font="default" size="100%">High Pressure Chemical Engineering Proceedings of the 3rd International Symposium on High Pressure Chemical Engineering</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">1996</style></year></dates><publisher><style face="normal" font="default" size="100%">Elsevier</style></publisher><volume><style face="normal" font="default" size="100%">Volume 12</style></volume><pages><style face="normal" font="default" size="100%">417-422</style></pages><isbn><style face="normal" font="default" size="100%">0921-8610</style></isbn><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The extraction of cork from cork-oak (Quercus suber L.) by high-pressure dioxane and supercritical CO2 mixtures was studied at 170 bar and in the temperature range of 160°C - 180°C. Suberin is preferably extracted, but extraction percentages were lower than 46%. Lignin extraction percentages are lower than 11%. Extraction selectivity did not change significantly with extracting fluid composition. The results so far obtained support the idea of the existence of an extensive polymeric system across the cell wall and the concept of a close interaction of suberin and lignin, which hinders lignin depolymerization and solubilization in the high-pressure fluid. Fourier transform infrared spectra of cork, extraction residues and extracts are also presented.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">THE CELLULAR STRUCTURE OF CORK FROM QUERCUS SUBER L</style></title><secondary-title><style face="normal" font="default" size="100%">IAWA Bulletin</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">1987</style></year></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">213-218</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The main characteristics of the cellular struc- ture of cork from Quercus suber L. are review- ed and comph;mented with new observations of virgin and reproduction cork by scanning electron microscopy. Particular emphasis is given to cell geometry and topology and to the corrugations that are observed in the cell walls. The effect of the growth season in these fea- tures is described. Large variations in cell size, wall thickness ajld corrugations are reported. Key words: Quercus SIlber, cork, cell gcometry, topology, cell wall corrugations.</style></abstract></record></records></xml>