一种分析时序逻辑电路的补充方法

介绍一种分析时序逻辑电路的补充方法,并应用于教学实践中。其特点是原理简单、易于理解、直观方便,相对于传统的分析方法,避免了对次状态方程的分析处理计算,有时比传统方法简便、快捷。通过两个示例展示其优越性。     

覆膜砂工艺参数优化的研究

通过对覆膜全过程的分析和优化实验，确定影响覆膜砂性能的工艺因素主要有：原砂的加热温度、加入树脂后的混砂时间、加入固化剂的混砂时间等，为了获得最佳的工艺参数，对各个工艺参数进行了正交实验。实验结果表明：为获得较高的热态抗拉强度，可以选用砂温180℃，加树脂后的混砂时间为100S，加固化剂后的混制时间为40S，加硬脂酸钙后的混制时间为30S；为获得较好的常温抗拉强度，可以选用砂温180℃，加树脂后的混砂时间为80s，加固化剂后的混制时间为30s，加硬脂酸钙后的混制时间为20s。     

单参数Wilson方程预测C_9-DMP体系汽液平衡

根据实测γ~∞_1用单参数Wilson方程预测均三甲苯-DMP和偏三甲苯-DMP二元体系汽液平衡,并推算均三甲苯-偏三甲苯-DMP三元体系的汽液平衡,与实测数据比较,均获得良好结果。     

Development of the semi-empirical equation of state for square-well chain fluid based on the Statistical Associating Fluid Theory (SAFT)

A semi-empirical equation of state for the freely jointed square-well chain fluid is developed. This equation of state is based on Wertheim’s thermodynamic perturbation theory (TPT) and the statistical associating fluid theory (SAFT). The compressibility factor and radial distribution function of square-well monomer are obtained from Monte Carlo simulations. These results are correlated using density expansion. In developing the equation of state the exact analytical expressions are adopted for the second and third virial coefficients for the compressibility factor and the first two terms of the radial distribution function, while the higher order coefficients are determined from regression using the simulation data. In the limit of infinite temperature, the present equation of state and the expression for the radial distribution function are represented by the Carnahan-Starling equation of state. This semi-empirical equation of state gives at least comparable accuracy with other empirical equation of state for the square-well monomer fluid. With the new SAFT equation of state from the accurate expressions for the monomer reference and covalent terms, we compare the prediction of the equation of state to the simulation results for the compressibility factor and radial distribution function of the square-well monomer and chain fluids. The predicted compressibility factors for square well chains are found to be in a good agreement with simulation data. The high accuracy of the present equation of state is ascribed to the fact that rigorous simulation results for the reference fluid are used, especially at low temperatures and low densities. This paper was presented at the 8th APCChE (Asia Pacific Confederation of Chemical Engineering) Congress held at Seoul between August 16 and 19, 1999.     

应用微扰理论（PHCT）诠释MH—55状态方程

用硬链微扰理论分析了ＭＨ－５５型状态方程。首次改进了该方程中的参考项，以ＣＳ硬球方程替代了原来的ｖａｎｄｅｒＷａａｌｓ斥力项，使改进后的ＭＨ－５５方程计算范围扩大到汽液两相。     

Production of β-SiC by pyrolysis of rice husk in gas furnaces

Short fibers and fine particles of β-SiC were obtained by pyrolysis of Colombian rice husk (RH). The synthesis of SiC was carried out in a gas furnace: a mathematical model was developed in order to design and build this equipment and the process was optimized using an experimental design that included variables such as temperature, pyrolysis time, type of catalyst, and process atmosphere. The obtained material was characterized by using FTIR, DRX and SEM for microstructural characterization and EDS technique for chemical analysis.     

Experimental design approach to calcium carbonate precipitation in a semicontinuous process

The production of precipitated calcium carbonate, PCC, by a semicontinuous process of slaked lime carbonation was performed in a bench-scale chemical reactor, fully controlled by means of custom built electronics and software for the personal computer. Calcite crystals, with different characteristic morphologies (rhombohedral, truncated prismatic, scalenohedral, spheroidal or chain-like agglomerates) were produced by varying a range of process parameters, like temperature, supersaturation, gas mixture flow rate, stirring rate and mass concentration of Ca(OH)₂ suspension. In order to identify the effects of the chosen process parameters on the PCC morphology and on the related specific surface area, as well as on the extent of CO₂ conversion, an empirical approach based on the experimental design techniques was employed. A multiple correlation analysis of the obtained data suggests that temperature and conductivity significantly influence the PCC morphology, while CO₂ conversion is principally influenced by stirring rate, conductivity and gas mixture flow rate.     

针对信息安全专业《近世代数》课程改革的探讨

针对信息安全专业的《近世代数》教学,分析信息安全专业学生与数学专业学生在《近世代数》学习上存在的差异性,并因此提出如何调整《近世代数》的教学内容使其更适合信息安全专业学生的学习,探讨针对信息安全专业《近世代数》学习的教学方法改革,从而提高信息安全专业学生学习《近世代数》的积极性和效果。     

精确实验数据曲线方程的求解

针对精确实验数据的曲线拟合方程化处理方法已不再适应高精度测试技术的问题,提出了用三次样条插值函数进行曲线方程化处理的新方法,并创建了用MATLAB语言编写遗传算法程序进行曲线斜率求解的方法,通过实例表明,采用遗传算法求解出的三次样条插值函数非常适合精确实验数据的曲线方程化处理。