纤维状二氧化硅纳米球的水热合成与表征

为了得到高比表面且尺寸均一的纤维状二氧化硅纳米球,采用静止和搅拌水热反应法制备了该类纳米粒子,探讨了制备机理及影响生长的因素.以同反应条件下微波法制备所得纤维状二氧化硅纳米球为参比样品,通过扫描电镜和透射电镜(SEM和TEM)观察了微波反应法和水热反应法所得3类纤维状二氧化硅纳米球的形貌和结构特征、傅里叶变换红外光谱(FT-IR)考察了纳米粒子的化学组成、X射线衍射谱(XRD)探究了纳米粒子的体相结构信息,以及采用氮气吸附脱附手段揭示了纳米粒子的吸附脱附类型及孔径分布.结果表明:水热反应能够生成直径较大、形貌更为均匀的纳米球;搅拌水热反应效果更明显,产物尺寸更为均一;3种反应方式合成的纳米球具有相似的化学结构和化学官能团,都属于Ⅳ型吸附且滞后环属于H_3型;3类纳米球的比表面积(和孔体积)分别为480.156 m~2/g(1.287 cm~3/g)、464.757 m~2/g(0.654 cm~3/g)和429.351 m~2/g(0.726 cm~3/g).形貌和结构的差别归因于反应体系的压力和反应母液均匀程度,前者促使生成均匀的微乳液,后者促进生成均匀的反胶束.     

Computer Stochastic Processing of Fuze Overload

The method which can simulate the stochastic process of the overload during the course of a projectile launching is discussed in detail. The calculated theory bases on the principle of information diffusion in fuzzy theory. To approach the actual launching overload, the calculated theoretical overload is disposed by the white noise. The dynamic test is used to calculate the fuze response of the launching overload. Finally, the launching overload of a projectile fuze is simulated to verify the validity of the method. The result is found basically to be in accord with the actual launching overload of the fuze, and the calculation accuracy is perfect.     

排气管铸件缩孔、缩松缺陷的解决

通过对排气管铸件结构和原铸造工艺方案的分析,找出了铸件缩孔、缩松问题的原因。应用铸件均衡凝固技术,采取合理的工艺改进措施,有效地解决了生产初期铸件缩孔、缩松缺陷难题,取得了显著的经济效益。     

利用有效的营林措施控制和抵御病虫危害

本文叙述了利用有效的营林措施控制和抵御病虫危害。     

Mechanism Modeling and Simulation Based on Dimensional Deviation

To analyze the effects on motion characteristics of mechanisms of dimensional variations, a study on random dimensional deviation generation techniques for 3D models on the basis of the present mechanical modeling software was carried out, which utilized the redeveloped interfaces provided by the modeling software to develop a random dimensional deviation generation system with certain probability distribution characteristics. This system has been used to perform modeling and simulation of the specific mechanical time delayed mechanism under multiple deviation varieties, simulation results indicate the dynamic characteristics of the mechanism are influenced significantly by the dimensional deviation in the tolerance distribution range, which should be emphasized in the design.     

Temperature field simulation technology for thermostat electromechanical systems

Temperature field control of electromechanical system with constant temperature is one of the important factors that affects the accuracy of the system. Traditional ways of temperature detection cost a lot but have low responding sensitivity. To solve this problem, temperature field simulation using numerical simulation was done toward the electromechanical system, and the platform temperature field distribution as well as the process of the platform reaching the steady-state was analyzed. The research shows that the system temperature observing parameters are all within normal range and the temperature control structure is rational. In all, the research achievements have some engineering and theoretical values in improving the design of temperature control device and system accuracy.     

利用PHP在Internet/Intranet上开发动态Web页的技术

本文阐述了当前Internet/Intranet上新一代动态网页开发技术PHP的运行机制,以较丰富的实例论述了PHP的工作环境,语法结构和PHPLIB的基本组成及其开发方法。     

Computer Stochastic Processing of Fuze Overload

The method which can simulate the stochastic process of the overload during the course of a projectile launching is discussed in detail.The calculated theory bases on the principle of information diffusion in fuzzy theory.To approach the actual launching overload,the calculated theoretical overload is disposed by the white noise.The dynamic test is used to calculate the fuze response of the launching overload.Finally,the launching overload of a projectile fuze is simulated to verify the validity of the method.The result is found basically to be in accord with the actual launching overload of the fuze,and the calculation accuracy is perfect.