提高串联稳压电源稳定度的几个措施

影响稳压电源稳定度的因素很多，外部因素包括输入电压、负载、环境温度的变化，内部因素有基准电压、分压比、运放参数变化等，在分析诸因素对稳定度影响的基础上，从实验探讨的角度，提出了几个切实可行的措施。     

Mechanical and biochemical characterization of the contraction elicited by a calcium-independent myosin light chain kinase in chemically skinned smooth muscle

Summary The contraction induced by a Ca²⁺-independent myosin light chain kinase (MLCK-) was characterized in terms of isometric force (F_o), immediate elastic recoil (SE), unloaded shortening velocity (V_us), shortening under a constant load and ATPase activity of chemically skinned smooth muscle preparations. These parameters were compared to those measured in a Ca²⁺-induced contraction to assess the nature of cross bridge interaction in the MLCK-induced contraction. F_o developed in chicken gizzard fibers as well as SE were similar in contractions elicited by either agent. V_us in the contraction induced by MLCK-(0.36 mg/ml) was similar though averaged 39.3±8.9% less than V_us induced by Ca²⁺ (1.6x10^–6M) in the control fibers. Addition of Ca²⁺ (1.6x10^–6M) to a contraction induced by MLCK-resulted in small increases in both F_o and V_us. Shortening under a constant load was similar for both types of contractions. The contraction induced by MLCK-was accompanied by an increased rate of ATP hydrolysis. The MLCK-induced contraction is thus kinetically similar though not identical to a contraction induced by Ca²⁺. We conclude that with respect to actin-myosin interaction, MLCK- and Ca²⁺-induced contractions are similar.     

试论对技术开发项目的有效管理

在以科研项目的最终管理目标是实现成果转化的基础上，提出了利用市场调节的手段来强化技术开发项目的有效管理。     

Java环境下网上审批流程的设计及实现

针对某油田租赁企业的业务实际,开发了基于工作流控制的油田租赁企业网上审批流程系统,该系统采用MVC模式的Struts框架,将数字签名技术和工作流技术应用其中,实现了油田租赁业务相关单据、报表等文件的网上流转和审批,大大提高了企业的工作效率。     

物质的芳香性

本文在论述了物质经典的芳香性理论的基础上，提出了一种非平面立体结构的物质的芳香性的判断方法。     

基于现代远程教育的网络课件开发与研究

介绍了远程教育在国内外的发展现状 ,研究了网络多媒体课件的开发步骤及开发技术 ,并以开发实例加以分析 .     

关于中国建立判例指导制度的思考

判例在普通法法系国家中是一种重要的法律渊源，是法律的表现形式；民法法系国家一般不承认判例的约束力，但在法律实践中判例法实际存在。受两大法系相互融合，取长补短的影响，我国案例指导出现了判例化的倾向。鉴于我国制定法的局限性，建立判例指导制度已经非常必要，它可以带来多方面的好处，但也要注意一些问题。     

The C4-dicarboxylate transport system ofRhizobium meliloti and its role in nitrogen fixation during symbiosis with alfalfa (Medicago sativa)

TheRhizobium meliloti C₄-dicarboxylate transport (Dct) system is essential for an effective symbiosis with alfalfa plants. C₄-dicarboxylates are the major carbon source taken up by bacteroids. Genetic analysis of Dct^– mutant strains led to the isolation of thedct carrier genedctA and the regulatory genesdctB anddctD. The carrier genedctA is regulated in free-living cells by the alternative sigma factor RpoN and the two-component regulatory system DctB/D. In addition, DctA is involved in its own regulation, possibly by interacting with DctB. In bacteroids, besides the DctB/DctD system an additional symbiotic activator is thought to be involved indctA expression. Further regulation ofdctA in the free-living state is reflected by diauxic growth of rhizobia, with succinate being the preferred carbon source. The tight coupling of C₄-dicarboxylate transport and nitrogen fixation is revealed by a reduced level of C₄-dicarboxylate transport in nitrogenase negative bacteroids.     

酒精装车的微机控制

对酒精的进出仓库,用Apple-Ⅱ微机进行实时温度、浓度补偿,使计量正确;采用了分时技术能同时对酒精装桶和装槽车进行实时控制:通过键盘操作可用汉字打印用户发票及各种累计量等表格;还开发了一套简单易行的接口技术,使硬件系统方便可靠。本系统在上海酒精厂投入运行一年多来,证明具有操作方便、功能齐全、安全可靠,计量正确等优点,并获得较大经济效益。     

论机遇在科学中的发现

在科学探索中的机遇，需要具有二个方面的涵义：（１）有科学的头脑，用科学假说与科学思维来推测，符合历史发展的客观规律的逻辑思维来指导思路．（２）有促进机遇形成的条件，使机遇的形成具有逻辑性、完善性．