植物磷酸运转器的结构与功能研究进展

磷酸运转器作为调节植物光合产物运转的关键蛋白之一，一直是光合作用研究的重要内容，且多集中在对其运转的生理生化功能的研究。总结了不同类型植物的质体中磷酸运转器的基因结构及其特性，同时也比较了它们的功能。磷酸运转器由核DNA编码，分子量约为36000D。不同的磷酸运转器起源于同一祖先，后相续进化而形成。同一植物不同的基因编码不同的磷酸运转器。C3植物的磷酸运转器调节磷酸（Pi）、磷酸二羟丙酮（DHAP）和3-磷酸甘油酸（3PGA）之间的反向交换运输，而2-磷酸甘油酸（2PGA）、磷酸烯醇式丙酮酸（PEP）、葡萄糖-6-磷酸（G6P）很少或根本不被运输。C4和CAM植物叶绿体中的磷酸运转器除了上面提到的代谢物以外还运输PEP，植物根质体中磷酸运转器也运输G6P。植物同一片叶子不同的细胞具有不同的叶绿体磷酸运转器。表1参36     

CAD/CAM概况及其发展

CAD/CAM是计算机辅助设计和辅助制造的简称,是20世纪计算机应用的革命性贡献。为此,就CAD/CAM的概念及其发展情况,简要论述了该系统的工作过程,并指出了其越来越广泛的应用。     

剃齿修形及检测CAD／CAM系统的理论研究

为消除拖拉机变速箱齿轮副在剃齿加工过程中产生的齿形中凹和畸变，研制了剃齿修形及检测的ＣＡＤ／ＣＡＭ系统，建立了剃刀修形曲线方程，导出了左、右啮合线相对位置方程，研究解决了剃齿啮合周期内奇数点接触概率、数据处理与曲线拟合等问题。本系统经多年实践证明，效果良好。     

Pasture research in South Africa

The “systems approach” means that decision‐rich parts of any given system are considered quantitatively and in their proper context. This is done by using models of various kinds. A model can be built if an adequate information base exists for the system in question, and if decisions have been taken about the scope and focal point(s) of the model, its application, and its form. The systems approach is illustrated by outlining a general procedure for livestock enterprise planning. Some of the research and extension problems revealed, and new problems created, by this and other models, are mentioned.

Two matters of general concern are discussed. It is argued that the quality of leadership in agricultural research leaves something to be desired. Secondly, the class of agricultural scientists seems to be regrettably indifferent to the long‐term effects of its work, and blind to the needs of primitive food producers. The systems approach can contribute to improvement in both areas, as a result of forcing people to define clear objectives and order their priorities. There is a need for grassland and other research workers to state the objectives of their disciplines for the next 30 years.     

交互式计算机辅助夹具设计系统

利用Ｖｉｓｕａｌ Ｂａｓｉｃ５．０在Ｗｉｎｄｏｗｓ９８环境下给出了交互式计算机辅助夹具设计的总体结构,设计方法,系统组成,为夹具科学化生产提供了依据。     

Evapotranspiration and Mineral Content of Sedum kamtschaticum Fischer Under Saline Irrigation

An alternative water resource such as graywater could be used for irrigation on green roofs during hot, dry summers, although it contains salt. In this study, the response to high-salt stress of a C3–CAM (Crassulacean acid metabolism) intermediate species, Sedum kamtschaticum Fischer, was evaluated over a 2-month experiment in terms of evapotranspiration (ET) and chemical compounds in plant tissue in triplicate for both experiments. High ET (10–15 mm day^?1) was observed under non-stressed conditions. On the day following the first saline irrigation, the peak ET at noon decreased as much as one-third of the maximum. After 9 days, ET remained below 3 mm day^?1, corresponding mostly to evaporation from the wet soil surface. The balance of chemical component contents in leaves changed depending on the electrical conductivity of irrigation water electrical conductivity (EC_i). The potassium to sodium (K⁺/Na⁺) ratio, which indicates levels of sodium toxic for plant growth, decreased with higher EC_i, while it excluded sodium from roots. However, based on enhanced water use efficiency under higher EC_i regardless of reduced carbon dioxide (CO₂) assimilation under salinity stress, the plant’s method of photosynthesis shifted from C3 to CAM metabolism. These findings show that S. kamtschaticum could survive for more than 2 months under low or moderate salinity of irrigation water in hot conditions.     

木质音箱的数控加工

为充分利用木材的天然特性,科学高效地使用木质材料,提高木质产品附加值,本试验应用计算机辅助设计与制造(CAD/CAM)和数控加工技术探讨了复杂木质音箱的加工生产特性.试验根据产品结构要求,绘制三维模型,进行数控编程及数控加工,并对加工工艺进行优化设计.研究结果表明,CAD/CAM和数控加工技术可高效地生产高质量的木质产品.     

基于农机产品应用数字化设计技术的研究

结合在农机产品设计制造方面的经验,针对数字化设计技术的特点,论述了企业在产品开发过程中的创新设计、协作和集成等运用数字化需求,提出了面向农机产品开发过程的数字化设计平台体系结构,探讨了农业机械产品数字化设计技术的研究现状及未来的发展趋势,其应用将会使传统的农业机械设计制造技术发生革命性的变化.     

CAD/CAM在成型模具设计制造中的应用前景--以节水灌溉塑料器材为例

目前,传统模具设计制造技术根本不能满足市场对模具的要求。因此,研制和开发新的模具设计、制造技术势在必行。模具CAD/CAM技术正是在这种形势下被开发出来的,并在现代模具的生产中发挥了重要作用。为此,总结了CAD/CAM技术的特点,指出了节水灌溉器材的发展方向,阐述了CAD/CAM技术在节水灌溉塑料器材成型模具设计制造中的应用前景。     

CAD／CAM集成数控自动编程系统的研制

SAAPT-2(1/2)D NC自动编程系统能高效、准确地实现零件源程序到NC程序、NC穿空纸带的转换。该系统由几何处理模块、工艺处理模块、后置处理模块和子程序库组成。几何处理模块对零件源程序几何定义语句进行词法、语法检查和参数标准化计算;工艺处理模块根据标准化参数对运动语句及其它非几何定义语句进行处理,生成中间代码文件;后置处理模块将中间代码文件变成NC加工程序。