排序方式： 共有37条查询结果，搜索用时 15 毫秒
21.
He Guo-qing Zhang Xiu-yan Tang Xing-jun Chen Qi-he Ruan Hui 《Journal of Zhejiang University. Science. B》2005,6(8):825-831
The partition behaviors of β-1,3-1,4-glucanase, α-amylase and neutral proteases from clarified and whole fermentation broths
ofBacillus subtilis ZJF-1A5 were investigated. An aqueous two-phase system (polyethylene glycol (PEG)/MgSO4) was examined with regard to the effects of PEG molecular weight (MW) and concentration, MgSO4 concentration, pH and NaCl concentration on enzyme partition and extraction. The MW and concentration of PEG were found to
have significant effects on enzyme partition and extraction with low MW PEG showing the greatest benefit in the partition
and extraction of β-glucanase with the PEG/MgSO4 system. MgSO4 concentration influenced the partition and extraction of β-glucanase significantly. pH had little effect on β-glucanase or
proteases partition but affected α-amylase partition when pH was over 7.0. The addition of NaCl had little effect on the partition
behavior of β-glucanase but had very significant effects on the partitioning of α-amylase and on the neutral proteases. The
partition behaviors of β-glucanase, α-amylase and proteases in whole broth were also investigated and results were similar
to those obtained with clarified fermentation broth. A two-step process for purifying β-glucanase was developed, which achieved
β-glucanase recovery of 65.3% and specific activity of 14027 U/mg, 6.6 times improvement over the whole broth.
Project (No. 20276064) supported by the National Nature Science Foundation of China 相似文献
22.
正整数n的分拆是指将正整数n表示成一个或多个正整数的无序和.而等差分拆是一种有限制条件的分拆.在这方面的研究有一些结果(见文献[4]-[6]),文章将文献[6]给出的一种形如N=2rdm(2r+1)的条件拓宽了一些,仍得到类似的结果.并推出了文献[5]中的一个结论. 相似文献
23.
不同的现场条件、工件情况,选用不同的焊接方法会得到不同的接头质量.本文利用rough知识发现理论,对大量实验数据进行清理,归纳出二维决策表.通过对决策表进行的等价类的划分,推出知识,进而找到不同焊接方法的规律. 相似文献
24.
基于DEA聚类分析的中国各地区资源、环境与经济协调发展研究 总被引：28，自引：0，他引：28
本文将数据包络分析(DEA)理论及DEA—最优分割聚类分析方法应用于中国各地区资源、环境与经济的协调发展评价中,提供了协调发展研究方法的新方向,并根据实际情况对计算结果作出分析,提出相应的对策建议。 相似文献
25.
基于交叉熵方法提出了一种启发式划分测试用例选择策略。该策略在待测软件参数已知的条件下,以总的测试费用最小为目的,利用交叉熵方法通过调整各个子域中测试用例选择的概率来选择测试用例。 相似文献
26.
27.
Kersten Hall 《Endeavour》2019,43(4):100708
The invention of partition chromatography by the biochemists Archer Martin and Richard Synge in 1941 offered crucial insights into the structure and function of DNA, insights at least as important as those from X-ray crystallography. Even so, the role that partition chromatography played in molecular biological studies is far less well known. Using new archival material, this article describes the origins of Martin and Synge’s work, arguing that their achievement was far more than a new technical innovation; it went on to have a profound impact on the development of molecular biology to an extent that scholars have insufficiently appreciated. 相似文献
28.
John Hutnyk 《Inter-Asia Cultural Studies》2018,19(4):610-626
ABSTRACTRecent film and television treatment of South Asia from UK producers have introduced new angles on the violent politics of colonial past, whether this be the activities of the East India Company in the early days of Empire, or about Partition, at the ostensible Raj’s end. The controversy over Gurinder Chadha’s 2017 film Viceroy’s House is taken as an opportunity to consider the new South Asian film and television studies and the emergent scholars that are challenging conventional media studies models. The co-constitution of here and there is given as an analytic lens through which to comprehend representation and stereotyping in films “about” politics in South Asia, and the view taken is that a debilitating divide and rule, via mechanisms of representation, remains strongly in place, despite the fighting efforts of the new South Asian media scholarship. 相似文献
29.
IP地址是TCP/IP协议在网络层的地址,用来唯一地标识每台接入互联网的主机。本文涉及的相关知识主要包括:IP地址的基本概念,IP地址的分类方法,特殊的IP地址类型,IP地址的划分方式。 相似文献
30.