<?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%">Evaluation of holm oak (Quercus ilex) wood as alternative source for cellulose pulp</style></title><secondary-title><style face="normal" font="default" size="100%">CELLULOSE CHEMISTRY AND TECHNOLOGY</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%">EDITURA ACADEMIEI ROMANE</style></publisher><pub-location><style face="normal" font="default" size="100%">CALEA 13 SEPTEMBRIE NR 13, SECTOR 5, BUCHAREST RO-76117, ROMANIA</style></pub-location><volume><style face="normal" font="default" size="100%">40</style></volume><pages><style face="normal" font="default" size="100%">53-61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Preservation of forests and increasing environmental awareness have focused research on the exploration of alternative resources for papermaking, a possible source being holm oak wood. The paper reports on the influence of some independent variables in the soda pulping of holm, oak wood \{[\}viz., temperature (135-195 degrees C), operation time (30-90 min) and active alkali concentration (10-20\%)] on the yield, hollocelulose, alpha-cellulose and lignin content, brightness, viscosity and kappa index of the pulps considered. By using a central, composite, factorial design, equations relating each dependent variable to different independent variables were derived, reproducing the experimental results for the dependent variables with errors below 10%. High pulp yield values were obtained under low operating variable conditions. To obtain the best results in brightness, viscosity and kappa index, operation under high values of the independent variables, the kappa index excepted, is necessary. To obtain a suitable value for this parameter, operation at low temperature is recommended. By applying TCF bleaching (A(1)OA(2)ZRP) in pulps obtained under extreme and central conditions of the pulping process, better values for kappa index (3.4) and brightness (83.8 ISO) result for the pulp obtained under maximum operating conditions. Nevertheless, considerable viscosity losses occur under Such conditions.</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%">Soda-anthraquinone, kraft and organosolv pulping of holm oak trimmings.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource 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%">97</style></volume><pages><style face="normal" font="default" size="100%">2110-2116</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The operating conditions for an organosolv (ethyleneglycol) and two alkaline (soda-anthraquinone and kraft) processes for obtaining cellulose pulp and paper from holm oak (Quercus ilex) wood trimmings were optimized. A range of variation for each process variable (viz. temperature, cooking time and soda or ethyleneglycol concentration) was established and a central composite experimental design involving three independent variables at three different variation levels was applied. The results obtained with the three cooking processes used were compared and those provided by the kraft process were found to be the best. Thus, the tensile index values it provided (5.9-16.3 N m/g) were 23.7% and 41.5% better than those obtained with the soda-AQ and ethyleneglycol processes, respectively. Also, the kraft process provided the best burst index, brightness and kappa number values. Based on the optimum working ranges, the temperature and cooking time were the variables resulting in the most and least marked changes, respectively, in pulp properties.</style></abstract><accession-num><style face="normal" font="default" size="100%">16269242</style></accession-num></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%">ilex subsp. ballota) DE MONTE BAJO TRAS DISTINTAS INTENSIDADES DE RESALVEO SEIS AÑOS DESPUÉS DEL FUEGO. RESULTADOS PRELIMINARES</style></title><secondary-title><style face="normal" font="default" size="100%">III Congreso Forestal Español</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2001</style></year></dates><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In a post-fire coppice forest of Quercus ilex different thinning intensities (0%, 53%, 88% and 100%) were carried out in order to evaluate their effects on the dynamic of the forest. The following spring after treatments, there were not significative differences for no thinning intensity on diameter relative growth but, on the contrary, there were differences for height relative growth between control plots and 88% thinning intensity. The higher resprouting percentage is reached for the treatment of 88% thinning intensity, while the lowest is registered in the control plots. Finally, the specific leaf area is higher for resprouters in control plots than in the treated ones. K.W.:</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%">Responses of the trunk routes of a harvester ant to plant density</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">1993</style></year></dates><volume><style face="normal" font="default" size="100%">93</style></volume><pages><style face="normal" font="default" size="100%">109-113</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Messor barbarus is a Mediterranean harvester ant that constructs physically defined trunk routes on the ground to connect nest entrances with foraging areas. Some responses of these trunk routes to plant density (and therefore resource abundance) were analyzed by testing the preferential allocation of different parts (trunk route ends, segments and branching points) in a patchy environment. Maps of grass density in four categories and Messor barbarus trunk routes were compiled for a Mediterranean pasture in Central Spain over four con- secutive years. The proportions of the density categories in each year were used to calculate random expected fre- quencies of the trunk route points and the predominance of higher or lower grass densities. Trunk route ends discriminate and selectively reach patches with a greater abundance of resources in all study years. Branching points are also allocated preferentially in areas with higher vegetation density, but only in years with a predom- inance of the higher categories of grass density. In these years, the colonies of Messor barbarus have a &quot;phalanx&quot; strategy at a colonial level, and branching is more profuse. Finally, trunk route segments do not indicate any preference for crossing determined vegetation den- sities, but rather connect successive branching points or trunk route ends by the shortest route. These results concur with a model of structural strategy change (&quot;guerilla&quot; - &quot;phalanx&quot;) (Hutchings 1988) at the level of trunk routes. They are probably constituted by &quot;tran- sitory&quot; sections with few branches, that expand other more profusely branched sections which are more dedi- cated to foraging.</style></abstract></record></records></xml>