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以经分子蒸馏后的混合生育酚粗品为原料,采用离子交换法将混合生育酚以及生育酚同系物进行分离。研究发现强碱性树脂对生育酚的静态吸附需要7h左右能达到平衡。树脂吸附生育酚的过程是个放热过程,随着温度的升高,生育酚的吸附量明显下降,35℃干树脂对生育酚的吸附最大值可达到506.1mg/g。常规的静态试验所得到的表观吸附等温线是条折线,这一特异性的现象是原料中游离脂肪酸对生育酚竞争吸附的结果,树脂对脂肪酸的亲和力要大于对生育酚的亲和力。在动态试验中,流出曲线表明生育酚各同系物流出顺序与其酸性大小有关,酸性最弱的α-生育酚最先穿透,其次是β+γ一生育酚,而酸性最强的δ-生育酚则最后穿透。随着进料质量浓度和流速的增大,系统的非理想性增强,卷起现象减弱。在描述解吸行为的解吸曲线中,各组分卷起的程度大小是:δ-生育酚>β+γ-生育酚>α-生育酚。 相似文献
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INTRODUCTIONThe palmitoleicacidand 9,12 octadecadienoicacidcontainedinpeanutoilaretwokindsofusefulpharmaceuticalmaterialsinatraditionalChinesemedicine ,whichisusedtotreatmanyskindiseases[1— 3 ] ,suchasVerrucavulgarisandCodylomaacuminanta .However,thesep… 相似文献
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论述了新型分离技术如超临界流体萃取、膜分离、分子蒸馏技术的原理及特点,介绍了它们在天然油脂工业中的应用研究进展,并探讨了其应用前景及存在的问题。 相似文献
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采用CFD模拟装备标准透平桨或45°-斜向上桨搅拌反应器内部流体力学特性 总被引:2,自引:1,他引:2
The hydrodynamic characteristics generated by the standard Rushton or 45°-upward pitched- blade-turbine (PBT) impellers in a baffled reactor are numerically simulated for different off-bottom clearances (C = 1/3Hand 1/2H) and agitator speeds (100, 150, 200, 250 and 300r.min-1) by using FLUENT code (Version 5.4). Theresults are compared with the experimental and simulated data in the published papers and good agreement isobserved. The shapes of the profile of mean velocities seem independent to the speed of agitators under theexperimental conditions (100-300 r.min-1). 相似文献
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Bioventing is conducted on one-dimensional soil columns. A numerical model is developed for simulating the mass exchange, adivective and dispersive transport and biodegradation of toluene. The model parameters are estimated independently through laboratory batch experiments, or from literature. Simulations are found to provide reasonable agreement with experimental data. Experimental results show that toluene removal due to biodegradiation is more important at the later stage. The total cleanup time when NAPL (non-aqueous phase liquid) phase exists was twice more than that without NAPL. Sensitivity analysis of parameters suggests that model predictions are mainly dependent on mass transfer coefficient and microbial parameters, such as the half-saturation coefficient and maximum specific substrate utilization rate. 相似文献