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81.
This paper describes an innovative method for the immobilization of acylase I, which was entrapped into the CA-CTA micropore membrane. The most suitable casting solutions proportion for immobilizing the enzyme was ob tained through orthogonal experiment. Properties of the enzyme membrane were investigated and compared with those of free enzyme and blank membrane. The thermal stability and pH stability of the enzyme inside the membrane were changed by immobilization. The optimum pH was found to be 6.0, which changes 1.0 unit compared with that of free acylase I. The optimum temperature was found to be about 90 ℃C, which is higher than that of free acylase I (60 ℃). Experimental results showed that immobilization had effects on the kinetic parameters of acylase I. 相似文献
82.
郝宁波 《安阳师范学院学报》2005,(5):65-68
介绍了自动频率规划及用遗传算法如何进行自动频率规划的方法,并说明了对遗传算法的各个算子的设计方法及原因.提出了如何利用正交试验设计的方法来科学地设置参数.同时将正交试验方法引入通信领域中,提出了用正交试验设计方法设置参数. 相似文献
83.
通过回顾几何自动推理与几何软件的历史与研究现状,探讨了几何自动推理系统的发展,得出几何自动推理系统应向网络化发展的结论。 相似文献
84.
The construction of the cables is a key step for erecting suspen-dome structures. In practical engineering, it is difficult to ensure that the designed pre-stresses of cables have been exactly introduced into the structures in the site; so it is necessary to evaluate the influence of the variation of the pre-stresses on the structural behavior. In the present work, an orthogonal design method was employed to investigate the pre-stressed cables' sensitivity to the suspen-dome system. The investigation was concentrated on a Kiewitt suspen-dome. Parametric studies were carried out to study the sensitivity of the structure's static behavior, dynamic behavior, and buckling loads when the pre-stresses in the cables varied. The investigation indicated that suspen-dome structures are sensitive to the pre-stresses in all cables; and that the sensitivity depended on the location of the cables and the kind of structural behavior. Useful suggestions are given at the end of the paper. 相似文献
85.
本文研究了黑糯玉米多糖的提取及两种脱蛋白分离工艺的比较.采用热水浸提、醇沉法提取黑糯玉米多糖,用两种改进的方法(氯仿-正丁醇法和三氯乙酸-正丁醇法)脱除蛋白质,以脱蛋白率为指标,通过正交实验L9(34)确定最佳脱蛋白分离工艺后,对比两种方法的最佳组合粗多糖得率及510nm处吸光值的差异.结果表明:三氯乙酸-正丁醇法比氯仿-正丁醇法的脱蛋白效果好,最佳水平脱蛋白率为70.69%,多糖得率仅为67.87%;氯仿-正丁醇法最佳水平脱蛋白率为51.39%,多糖得率为80.31%.本文建立的优化工艺可为黑糯玉米多糖的分离制备提供参考. 相似文献
86.
Grizzi F Franceschini B Fiamengo B Russo C Dioguardi N 《Journal of Zhejiang University. Science. B》2007,8(4):217-220
Hepatocellular carcinoma (HCC) remains one of the major public health problems throughout the world. Although originally associated with tumorigenic processes, liver angiogenesis has also been observed in the context of different liver inflammatory, fibrotic, and ischemic conditions. Here we investigate the fractal dimension as a quantitator of non-Euclidean two-dimensional vascular geometry in a series of paired specimens of primary HCC and surrounding non-tumoral tissue, and discuss why this parameter might provide additional information regarding cancer behavior. The application of fractal geometry to the measurement of liver vascularity and the availability of a computer-aided quantitative method can eliminate errors in visual interpretation, and make it possible to obtain closer-to-reality numerals that are compulsory for any measurement process. 相似文献
87.
本文利用H_0~1(Ω)空间的正交分解,克服了所讨论的椭圆方程对应的变分泛函因涉及特征值造成的验证山路几何的困难,得到了一对非平凡解的存在性结论. 相似文献
89.
90.
通过讨论Laplace算子的正交变换形式不变性,证明了在正交变换条件下,不同区域之间有形如Green公式的关系.作为这个结论的一个特殊情形,指出并证明了在旋转正交变换之下,推广以后的Green公式在形式上也具有不变性. 相似文献