Data acquisition system for chemical kinetic studies

A microcomputer-interfaced data acquisition system for chemical kinetics (interfacing with laboratory analogue instruments) has been developed. Analogue signals from instruments used in kinetics experiments are amplifed by a wide-range adjustable high-gain operational amplifier and smoothed by an op-based filter, and then digitized at rates of up to 10⁴ samples per channel by an ADC 0816 digitizer. The ADC data transfer and manipulation routine was written in Assembler code and in high-level language; the graphics package and data treatment package is in Basic. For the various sampling speeds, all of the program can be written using Basic-Assembler or completely in Assembler if a high sampling rate is needed. Several numerical treatment methods for chemical kinetics have been utilized to smooth the data from experiments.The computer-interfaced system for second-order chemical kinetic studies was applied to the determination of the rate constant of the saponification of ethyl acetate at 35°C. For this specific problem, an averaging treatment was used which can be called an interval method. The use of this method avoids the diffcully of measuring the starting time of the reaction. Two groups of experimental data and results were used to evaluate the systems performance. All of the results obtained are in agreement with the reference value.     

NC74-1型氨合成催化剂的升温还原及应用

介绍了NC74-1氨合成催化剂在山东华鲁恒升化工股份有限公司大氮肥氨合成的装填、升温还原及使用情况。     

Influence of deposition pressure on properties of ZnO: Al films fabricated by RF magnetron sputtering

Transparent conductive aluminum doped zinc oxide(ZnO:Al,AZO) films were prepared on glass substrates by rf(radio frequency) magnetron sputtering from ZnO: 3wt% Al_2O_3 ceramic target. The effect of argon gas pressure(PAr) was investigated with small variations to understand the influence on the electrical, optical and structural properties of the films. Structural examinations using X-ray diffraction(XRD) and scanning electron microscopy(SEM) showed that the ZnO:Al thin films were(002) oriented. The resistivity values were measured by four-point probe with the lowest resistivity of 5.76×10~(-4) Ω?cm(sheet resistance=9.6 Ω/sq. for a thickness=600 nm) obtained at the PAr of 0.3 Pa. The transmittance was achieved from ultravioletvisible(UV-VIS) spectrophotometer, 84% higher than that in the visible region for all AZO thin films. The properties of deposited thin films showed a significant dependence on the PAr.     

四维混沌系统及其在图像加密中的应用

传统基于低维混沌系统的图像加密算法往往具有密钥空间较小、安全性较差的问题。针对这些问题,首先提出了一类新的平衡点不稳定的四维离散混沌系统,通过数值仿真对该类系统进行了动力学行为分析,正的Lyapunov指数的个数可以达到三个。同时并基于该类混沌系统设计了一个新的图像加密方案,并进一步对明密文的分布直方图、相关系数、信息熵以及加密方案对参数的敏感性进行了分析。分析结果表明,该加密方案抵抗外来攻击的能力强,密钥空间可达2996△,具有较高的安全性。     

微波加热法合成蜂窝状堇青石载体Al2O3涂层

采用微波加热法在堇青石蜂窝陶瓷基体表面涂覆多孔Al2O3涂层,研究了制备条件对堇青石蜂窝陶瓷表面Al2O3涂层中Al2O3的质量分数的影响。通过BET、SEM对涂层结构及形貌进行了表征,结果表明,采用微波加热法制备的Al2O3涂层均匀、稳定,具有较大的比表面积、孔容和较高的Al2O3质量分数。     

Effect of poling on piezocatalytic removal of muti-pollutants using BaTiO3

The BaTiO₃ powder was prepared via a solid-state reaction route. It was studied for the degradation of bacterial cells, dye, and pharmaceuticals waste using ultrasonically driven piezocatalytic effect. The bacterial catalytic behavior of poled BaTiO₃ was remarkably increased during ultrasonication (10% E coli survival in 60 minutes). The structural damages were illustrated using scanning electron micrographs of bacterial cells which demonstrated morphological manifestations under different conditions. Methylene blue (MB dye), ciprofloxacin and diclofenac were also cleaned using the piezocatalytic effect associated with the poled BaTiO₃ powder. Around 92, 85, and 78% of degradations were observed within 150 minutes duration for methylene blue, ciprofloxacin, and diclofenac, respectively.     

A novel spherical-ordered macroporous CuO nanocatalyst for the electrochemical reduction of carbon dioxide

Journal of Applied Electrochemistry - The electrocatalytic reduction of CO2 is a promising research direction in resource utilization and sustainable energy development. However, there is still a...     

一种新型金刚石磨具树脂结合剂的制备

本文介绍了一种新型的操作工艺简单、耐水、耐热、耐酸碱溶液的环氧树脂结合剂的制备方法：结合剂采用环氧树脂和聚酰胺固化体系，并用液体端羧基丁腈橡胶(CTBN)对环氧树脂进行改性，在固化剂中添加改性固化利A提高固化物的耐热性。此树脂结合剂初始固化温度为3min，成型方便，是一种适于异形金刚石磨具使用的树脂结合剂C在150℃固化3h并在室温放置1天后，固化物具有高的硬度和耐热性以及优异的粘接性能，可以在150℃长期使用。     

MEASUREMENT AND INFLUENCE FACTOR＇S ANALYSING OF INTERFACIAL STRENGTH OF COMPOSITES

ＭＥＡＳＵＲＥＭＥＮＴＡＮＤＩＮＦＬＵＥＮＣＥＦＡＣＴＯＲ＇ＳＡＮＡＬＹＳＩＮＧＯＦＩＮＴＥＲＦＡＣＩＡＬＳＴＲＥＮＧＴＨＯＦＣＯＭＰＯＳＩＴＥＳ￥ＷａｎｇＬｉｎｇｓｅｎ；ＬｉｕＲｕｏｙｕ；ＺａｎｇＪｉｎｓｅｎ；ＦａｎＹｉ（ＲｅｓｅａｒｃｈＩｎｓｔｉ...     

张力减径过程快速仿真系统建模问题的研究

在空间解析曲面模型理论基础上,采用三维弹塑性大变形有限元方法,建立了复杂几何形体动态约束模型,解决了张力减径过程中的矩阵变换、模型转换和多机架全系统仿真的问题。