添加纤维二糖,淀粉水解液对纤维素酶制备的影响

里氏木霉（ＴｒｉｃｈｄｅｒｍａｒｅｓｅｉＲｕｔＣ３０）以经蒸汽爆破预处理的玉米秆为底物制备纤维素酶,产酶ｐＨ值维持在５．０左右,底物浓度为３．７５％（玉米秆,干基）时,产酶３天,滤纸酶活力和纤维二糖酶活力达１．７６ＩＵ／ｍＬ和０．３８ＩＵ／ｍＬ,纤维二糖酶活力高,酶水解得率达８０．２％;在试验培养基中添加纤维二糖对纤维素酶的合成具有抑制作用,培养基中添加纤维二糖浓度在０．２５～１．５０ｇ／Ｌ时,滤纸酶活力和纤维二糖酶活力同时下降３０％～４０％;淀粉水解液对纤维毒酶合成的影响是由葡萄糖的抑制和复合糖的诱导共同作用的结果,在用本研究培养基制备纤维酶过程中添加淀粉水解液,从经济角度来说是不适宜的。     

对电子束蒸发沉积的ZnO：Al膜电学性能的研究

使用电子束蒸发法沉积了铝掺杂的氧化锌透明导电膜。     

高层建筑侧向刚度计算的分域样条虚边界元法

采用弹性力学平面问题的分域样条虚边界元法导出了高层建筑平面抗侧力结构的侧向刚度矩阵．该方法只需要输入少量数据,便可准确迅速地计算出平面结构的侧向刚度矩阵,据此即可对整个结构进行静力和动力分析．     

“程序设计”联机测评系统的研究

本文讨论一个程序设计联机测评系统（ＰＬＯＥＳ）．系统由三大模块组成．包括试题库管理模块、考试模块和评卷模块．系统的实现面向程序设计语言．挂接不同语言的题库和评卷模块就能实现不同语种的考试．系统可评阅六种题型包括程序设计题．     

桁架结构拓扑优化设计的模拟退火算法

研究了平面桁架结构拓扑优化设计的模拟退火算法．构造了一个双重控制Ｍｅｔｒｏｐｏｌｉｓ准则处理应力约束,提出了一个基于力平衡的启发式准则,以实现优化过程中单元的自动增删．算例表明,该方法能够克服桁架结构拓扑优化中因存在非凸星形可行域而造成的拓扑优化求解困难．     

“S”形刃球头立铣刀的研究（Ⅰ）──数学模型

在分析球头立铣刀刃磨方法的基础上,建立了“Ｓ”形刃球头立铣刀前、后刀面以及切削刃的数学模型．模型的建立对“Ｓ”形刃球头立铣刀几何参数的分析及优化、切削机理的研究、刃磨参数的选择以及刃磨装置的设计都将具有理论意义;对加快“Ｓ”形刃球头立铣刀的国产化制造具有实用价值．     

Almost sure convergence of weighted sums of NA sequences

For double arrays of constants {a _ni, 1≤i≤k _n, n≥1} and NA r.v. 's {X _n, n≥1}, conditions for almost sure convergence of are given. Both casesk _n ↑ ∞ andk _n=∞ are treated. A Marcinkiewicz-type theorem for i. d. NA sequences is obtained as a special case. Supported by the National Natural Science Foundation of China Cheng Riyan: born in 1968, MS student     

关于极大极小定理的一点注记

本文证明了关于Von Neumann型极大极小原理的许多结果,可作为论文“不动点型极大极小定理的一点推广”的直接结论。     

An independent microbial flora of the epithelium and its role in the ecomicrobiology of the rumen

IT has been suggested that the bacterial flora of the rumen should be considered as three distinct, interacting populations-the bacteria of rumen fluid (the population which has been studied most extensively), the bacteria associated with food particles, and the bacteria adhering to the epithelial wall of the organ(1). Until now, studies of the 'epithelial' population have been restricted to examination of postmortem samples of wall tissue and its attached bacterial flora(2-5). A recently developed technique(6) for feeding young sheep for long periods solely by infusion of protein and other essential nutrients into the abomasum, and of volatile fatty acids and bicarbonate buffer into the rumen, has provided us with an opportunity to study in isolation the role of the bacterial population of the wall in the ecomicrobiology of the rumen in the living animal. Our studies show that this population can exist independently of the other two populations, that it is primarily responsible for urea digestion in the rumen and that it initiates breakdown of dead epithelial tissue. Furthermore, our results point to an inverse relationship between ammonia concentration and ureolytic activity in rumen fluid, which may account for the control which ammonia exerts over flux of urea across the rumen wall(7-9).