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91.
92.
Concanavalin A (Con A) immobilized poly(2‐hydroxyethyl methacrylate) (PHEMA) beads in a spherical form (100–150 μm in diameter) were used for the affinity chromatography purification of human immunoglobulin G (IgG) from aqueous solutions and human plasma. PHEMA adsorbents were prepared by suspension polymerization. Bioligand Con A was then immobilized by covalent binding onto PHEMA beads. The maximum IgG adsorption on the PHEMA/Con A beads was observed at pH 6.0. The nonspecific IgG adsorption onto the plain PHEMA adsorbents was very low (ca. 0.17 mg/g). Higher adsorption values (up to 54.3 mg/g) were obtained when the PHEMA/Con A beads were used from aqueous solutions. A higher adsorption capacity was observed for human plasma (up to 69.4 mg/g) with a purity of 82.5%. The adsorption capacities of other blood proteins were 2.0 mg/g for fibrinogen and 4.2 mg/g for albumin. The total protein adsorption was determined to be 76.0 mg/g. IgG molecules could be repeatedly adsorbed and desorbed with the PHEMA/Con A beads without noticeable loss in the IgG adsorption capacity. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1202–1208, 2005 相似文献
93.
Broadband dielectric relaxation spectroscopy (DRS), thermally stimulated depolarisation currents (TSDC), differential scanning calorimetry (DSC) and to a lesser extent water uptake measurements, were employed to investigate molecular mobility, morphology and crystallization/melting events of PEG in poly(imide-amide)-polyethylene glycol hybrid networks (PIA-PEG) with short (Mn=1000 g/mol) and long (Mn=3400 g/mol) PEG crosslinks. The results obtained suggest long range connectivity of the PEG component in the hybrids with short PEG crosslinks at PEG content higher than 40 wt% and in these with long PEG crosslinks at PEG content higher than 20 wt%. Crystallization of the PEG component is observed by DSC in the hybrids with the longer crosslinks at sufficiently high content of PEG, only. The glass transition temperature, Tg, of PEG component in the hybrids with the shorter PEG crosslinks is shifted to higher temperatures compared to that of the hybrids with longer PEG crosslinks, while suppression of the glass transition of the PEG component is observed in the hybrids with the shorter PEG crosslinks at PEG content lower than 40 wt%. The results are discussed in terms of constraints to segmental motion of the PEG crosslinks, imposed by fixed PEG chain ends on the rigid PI chains. 相似文献
94.
A new kind of terpolymer membrane was employed to separate a permselective water–alcohol mixture. This membrane was prepared via the copolymerization of acrylonitrile, sodium salt styrene sulfonic acid (SStSA), and hydroxyethyl methacrylate in dimethylsulfoxide with azobisisobutyronitrile as an initiator. The reaction mechanism, resultant structure, and polymer composition were confirmed by IR and elemental analysis. The effects of the feed composition on the polymer composition, mechanical properties, thermal properties, and degree of swelling were investigated. It was found that water permeated through the membrane preferentially in a water/alcohol system. The flux increased with the increase of SStSA, but the separation factor decreased drastically with higher SStSA. For a 50 wt % water–ethanol mixture, a flux of 0.65 kg/m2 h and a separation factor of 212 were obtained at 30°C when the membrane containing the highest SStSA content was used. The capacities of the metal ions absorbed by the membranes were investigated in the study. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 244–250, 2003 相似文献
95.
针对深度确定性策略梯度算法(DDPG)收敛速度比较慢,训练不稳定,方差过大,样本应用效率低的问题,提出了一种基于随机方差减小梯度方法的深度确定性策略梯度算法(SVR-DDPG)。该算法通过利用随机方差减小梯度技术(SVRG)提出一种新的创新优化策略,将之运用到DDPG算法之中,在DDPG算法的参数更新过程中,加入了随机方差减小梯度技术,利用该方法的更新方式,使得估计的梯度方差有一个不断减小的上界,令方差不断缩小,从而在小的随机训练子集的基础上找到更加精确的梯度方向,以此来解决了由近似梯度估计误差引发的问题,加快了算法的收敛速度。将SVR-DDPG算法以及DDPG算法应用于Pendulum和Mountain Car问题,实验结果表明,SVR-DDPG算法具有比原算法更快的收敛速度,更好的稳定性,以此证明了算法的有效性。 相似文献
96.
以最严格水资源管理理念为前提,从最严格水资源管理下的区域水资源综合模拟、水资源管理分配,以及典型研究区流域水资源监测框架核心技术及考核指标的评价体系这4个方面,研究内陆干旱区实施最严格水资源管理的关键技术,且以天山北坡中段呼图壁河流域为典型示范区,揭示流域内水资源的供需规律,建立适应内陆干旱区的最严格水资源管理制度,为实现区域水资源的可持续利用以及支撑区域经济社会的可持续发展提供科学依据和决策建议,为干旱区贯彻和落实最严格水资源管理制度提供科技支撑。 相似文献
97.
98.
王稳 《吉林化工学院学报》2014,31(10):37-40
中国古典哲学认为:宇宙间一切事物都存在阴阳,一切事物变化无不是相互对应、阴与阳相互作用的结果。阴阳学说理论所体现的中华武术传统文化及思维方式更是典型,是武术理论必不可少的基本构架之一。通过分析、归纳武术技法哲理思想中所蕴涵的"阴阳互转"的哲学思想,希望最终达到与武术技法哲理思想的和谐统一,为进一步学习武术,修炼武术并以此提升习武者自身内涵起到积极作用。 相似文献
99.
通过感官评价研究锅包肉烹饪工艺条件对其感官品质的影响,同时利用正交试验对糖醋汁配比工艺参数进行优化研究。结果表明:选择里脊肉作为锅包肉原材料最优,锅包肉选用玉米淀粉挂糊最佳,锅包肉糖醋汁最优配比为番茄沙司含量为20%、蔗糖含量为35%、白醋含量为45%、食盐含量为1%。 相似文献
100.
Marine Harguindeguy Claire Antonelli Marie-Pierre Belleville José Sanchez-Marcano Céline Pochat-Bohatier 《应用聚合物科学杂志》2021,138(2):49669
Millimeter-size beads of gelatin are manufactured by dripping process to give enzyme supports qualified for micropollutants biodegradation in alternative wastewater treatment. The bead diameter is dependent on the tip diameter, the gelatin solution viscosity and the swelling of polymer chains in the collecting bath. Chemical crosslinking was performed with glutaraldehyde using optimal concentration to give mechanical and thermal properties suitable for application in stirred reactor in aqueous medium. Laccases from Trametes versicolor are grafted on the gelatin beads with glutaraldehyde. Sixty percentage of the initial enzymatic activity, evaluated by the oxidation of 2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt (ABTS) is maintained after 10 successive cycles of reaction. Thermal stability at 60°C of immobilized biocatalysts is improved when compared to free enzymes (45% vs 10% of relative activity after 6 h of incubation). The simplicity of the procedure to form gelatin beads and their properties make them promising bio-based and biodegradable support for enzyme immobilization. 相似文献