<?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><authors><author><style face="normal" font="default" size="100%">Cordeiro, N.</style></author><author><style face="normal" font="default" size="100%">Neto, C. P.</style></author><author><style face="normal" font="default" size="100%">Rocha, J.</style></author><author><style face="normal" font="default" size="100%">Belgacem, M. N.</style></author><author><style face="normal" font="default" size="100%">Gandini, A.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The organosolv fractionation of cork components</style></title><secondary-title><style face="normal" font="default" size="100%">HOLZFORSCHUNG</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">C-13 NMR</style></keyword><keyword><style  face="normal" font="default" size="100%">Cork</style></keyword><keyword><style  face="normal" font="default" size="100%">ethanol/water extraction</style></keyword><keyword><style  face="normal" font="default" size="100%">FTIR</style></keyword><keyword><style  face="normal" font="default" size="100%">organosolv fractionation</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus Suber L</style></keyword><keyword><style  face="normal" font="default" size="100%">suberin</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><volume><style face="normal" font="default" size="100%">56</style></volume><pages><style face="normal" font="default" size="100%">135 - 142</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Extractive-free cork from Quercus suber L. was submitted to organosolv fractionation and the effects of different process variables, such as ethanol/water ratio, temperature, time and the presence of acidic or alkaline catalysts, were studied. The variation of the relative proportions of extracted components, as a function of the processing conditions, could thus be established. Whereas the addition of 0.1 M acetic acid only increased the yield of extracted materials from about 15 to 23 %, the use of sodium hydroxide, at the same concentration, produced a jump to 76 %. In the case of the alkaline organosolv fractionation. an increase in process temperature, time and catalyst concentration led to an increase in the extraction yield, although in some cases this increase did not follow a sustained trend, as in the case of reaction time. Increasing the ethanol/water ratio led to a higher selectivity in favour of suberin extraction. Residual cork from different organosolv processes was characterised by FTIR and C-13 solid-state NMR. The latter technique provided some valuable information about both process selectivity and cork morphology, particularly with respect to the positioning of suberin macromolecules in the cell wall.</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: GENTHINER STRASSE 13, D-10785 BERLIN, GERMANY&lt;br/&gt;publisher: WALTER DE GRUYTER &amp; CO</style></notes></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%">Pascoal Neto, C.</style></author><author><style face="normal" font="default" size="100%">Rocha, J.</style></author><author><style face="normal" font="default" size="100%">Gil, A.</style></author><author><style face="normal" font="default" size="100%">Cordeiro, N.</style></author><author><style face="normal" font="default" size="100%">Esculcas, a P.</style></author><author><style face="normal" font="default" size="100%">Rocha, S.</style></author><author><style face="normal" font="default" size="100%">Delgadillo, I.</style></author><author><style face="normal" font="default" size="100%">de Jesus, J. D.</style></author><author><style face="normal" font="default" size="100%">Correia, a J.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">13C solid-state nuclear magnetic resonance and Fourier transform infrared studies of the thermal decomposition of cork.</style></title><secondary-title><style face="normal" font="default" size="100%">Solid state nuclear magnetic resonance</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Fourier Transform Infrared (citation)</style></keyword><keyword><style  face="normal" font="default" size="100%">Hot Temperature</style></keyword><keyword><style  face="normal" font="default" size="100%">Lignin</style></keyword><keyword><style  face="normal" font="default" size="100%">Lignin: chemistry</style></keyword><keyword><style  face="normal" font="default" size="100%">Lipids</style></keyword><keyword><style  face="normal" font="default" size="100%">Magnetic Resonance Spectroscopy</style></keyword><keyword><style  face="normal" font="default" size="100%">Membrane Lipids</style></keyword><keyword><style  face="normal" font="default" size="100%">Membrane Lipids: chemistry</style></keyword><keyword><style  face="normal" font="default" size="100%">Polysaccharides</style></keyword><keyword><style  face="normal" font="default" size="100%">Polysaccharides: chemistry</style></keyword><keyword><style  face="normal" font="default" size="100%">Spectroscopy</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1995</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1995///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/7773647</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">4</style></volume><pages><style face="normal" font="default" size="100%">143 - 151</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The thermal decomposition of cork has been studied by Fourier transform infrared (FTIR) spectroscopy and 13C solid-state nuclear magnetic resonance (NMR) spectroscopy with cross-polarization and magic-angle spinning (CP-MAS), high-power 1H decoupling (HPDEC) and cross-polarization depolarization-polarization (CPDP). Waxes and other soluble components of cork begin to decompose at ca. 150 degrees C. This is accompanied by partial decomposition of suberin, probably initiated at the points of attachment to the cell wall. The carbohydrates begin to decompose at ca. 200 degrees C. The decomposition of lignin begins at 250-300 degrees C, while suberin undergoes further degradation. Significant amounts of coke are formed in the process. At 400 degrees C cork has been transformed into coke with traces of partially decomposed suberin. The thermal decomposition of cork is dependent on the calcination time, particularly in the 200-350 degrees C range.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;accession-num: 7773647</style></notes></record></records></xml>