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81.
A novel mixed‐mode expanded bed adsorbent with anion‐exchange properties was explored with benzylamine as the functional ligand. The cellulose composite matrix, densified with stainless steel powder, was prepared with the method of water‐in‐oil suspension thermal regeneration. High activation levels of the cellulose matrix were obtained with allyl bromide because of the relative inertness of the allyl group under the conditions of the activation reaction. After the formation of the bromohydrin with N‐bromosuccinimide and coupling with benzylamine, the activated matrix was derived to function as a mixed‐mode adsorbent containing both hydrophobic and ionic groups. The protein adsorption capacity was investigated with bovine serum albumin as a model protein. The results indicated that the prepared adsorbent could bind bovine serum albumin with a high adsorption capacity, and it showed salt tolerance. Effective desorption was achieved by a pH adjustment across the isoelectric point of the protein. The interactions between the cell and adsorbent were studied, and the bioadhesion was shielded by the adjustment of the salt concentration above 0.1M. Stable fluidization in the expanded bed was obtained even in a 2% (dry weight) yeast suspension. The direct capture of target proteins from a biomass‐containing feedstock without extra dilution steps could be expected with the mixed‐mode adsorbent prepared in this work, and this would be especially appropriate for expanded bed adsorption applications. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
82.
Web社区是互联网中自组织程度较高的部分,它不是一个孤立系统,而是一个耗散系统,很多时候涨落无法耗散摔,导致社区运行不稳定.基尼系数可以用来衡量Web社区稳定性,通过基尼系数的简易计算公式计算社区内部成员积分或者其它参数,可以得出Web社区稳定性的度量.该度量对于研究和利用Web社区具有重要参考意义. 相似文献
83.
84.
Fabrice Martin Marc-Etienne Jan Samuel Rey-Mermet Brahim Belgacem Dong Su Marco Cantoni Paul Muralt 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2006,53(7):1339-1343
Polycrystalline A1N thin films were deposited by RF reactive magnetron sputtering on Pt(111)/Ti electrode films. The substrates were tilted by an angle ranging from 40 degrees to 70 degrees with respect to the target normal. A low deposition temperature and a high sputter gas pressure were found ideal for tilted growth. The resulting grain tilt angle amounts to about half the substrate tilt angle. For coupling evaluation, 5 GHz solidly mounted resonator structures have been realized. The tilted grain A1N films exhibited a permittivity in the 9.5-10.5 range and loss tangent of 0.3%. Two shear modes as well as the longitudinal mode could be clearly identified. The coupling coefficient k2(eff) of the fundamental thickness shear mode (TS0) was found to be about 0.5%, which is compatible with a c-axis tilt of about 6 degrees. 相似文献
85.
86.
在管理信息系统的开发以及分布式数据库系统的设计中,已开始使用面向对象的技术.本文论述了面向对象的设计特征,介绍了用于面向对象设计的各种实现语言,并着重分析了各种实现语言支特面向对象设计的能力. 相似文献
87.
本文着重介绍了构成《现代勘探决策理论系统》的5个主要计算机模块,即:生油岩热演化处理、求任意曲边形面积、数学模拟预测资源量、勘探经济评价分析及决策、辅助处理等模块。该系统曾在塔里木盆地和准噶尔盆地的油气资源评价和勘探决策中发挥了作用,受到了专家和用户的好评。 相似文献
88.
砼受压损伤力学本构模型的研究 总被引:15,自引:1,他引:14
本文利用MTS公司815.02型电液伺服试验系统对砼进行了等应变速率加载控制的应力一应变全曲线试验,应用不可逆热力学和内变量理论的成果建立了砼损伤力学模型,并用概率统计的观点分析了损伤的演化规律。由于考虑了不可逆变形的影响,本文所建本构模型与实验吻合较好。 相似文献
89.
The mixture of platelet-activating factor (PAF) and platelets produced significant contraction of guinea pigs' bronchus, while the contraction induced by PAF alone was mild relatively, the IC50 were 6.14 x 10(-7) mol/L and 6.32 x 10(-4) mol/L respectively. There was significant difference between these two groups (P < 0.05). When the platelets were pre-incubated with ginkgolides for 10 minutes in Tris-Tyrode's buffered saline, effects of the PAF and platelets mixture were significantly inhibited (P < 0.01). Exposure of guinea pigs' bronchus to PAF in vitro resulted in a loss of beta-adrenergic receptors and responses to isoproterenol, and this effect of PAF was prevented by prior incubation of the guinea pigs' bronchus with ginkgolides (P < 0.05). The results showed ginkgolides were a potent PAF antagonist. 相似文献
90.
通过力学性能评估和金相组织观察,研究五种热处理制度,两个周期的试验结果,确定了K418B合金细晶铸造整体涡轮的真空热处理工艺。 相似文献