New insights into the effects of silicon content on the oxidation process in silicon-containing steels

Simultaneous thermal analysis (STA) was used to investigate the effects of silicon content on the oxidation kinetics of silicon- containing steels under an atmosphere and heating procedures similar to those used in industrial reheating furnaces for the production of hot-rolled strips. Our results show that when the heating temperature was greater than the melting point of Fe₂SiO₄, the oxidation rates of steels with different silicon contents were the same; the total mass gain decreased with increasing silicon content, whereas it increased with increasing oxygen content. The oxidation rates for steels with different silicon contents were constant with respect to time under isothermal conditions. In addition, the starting oxidation temperature, the intense oxidation temperature, and the finishing oxidation temperature increased with increasing silicon content; the intense oxidation temperature had no correlation with the melting of Fe₂SiO₄. Moreover, the silicon distributed in two forms: as Fe₂SiO₄ at the interface between the innermost layer of oxide scale and the iron matrix, and as particles containing silicon in grains and grain boundaries in the iron matrix.     

压电陶瓷激振器定频激振能力的评价方法

提出了评价压电陶瓷激振信号的线性度指标,并基于自主研发的压电陶瓷激励反馈系统,对一款PZT陶瓷进行了实验研究.在分析其激振力的影响因素及影响规律的基础上,提出了压电陶瓷定频激振能力的评价方法.由实验数据建立了评价方程,得到了其定频激振的频率置信区间,使其可以更好地被应用到板壳类薄壁构件的高阶振动测试研究中.研究结果表明,压电陶瓷定频激振能力的总体特点是在低频状态下可实现高幅定频激励,而高频状态下仅能实现低幅定频激励.     

一种基于PIC16C54的双联气泵控制系统

简要介绍一种应用于气冷式高温工业电视的以 Ｐ Ｉ Ｃ１６ Ｃ５４ 微处理器为核心的双联气泵控制系统     

掺杂Li4SiO4材料的CO2吸附研究

Recycling and utilizing CO2 is very important significance to realizing energy saving and emission reduction. Lithium silicate (Li4SiO4) absorbents for CO2 were prepared by high-temperature solid-state reaction. Thermodynamic equilibrium of Li4SiO4 absorp-tion CO2was discussed using the HSC5.0 code. The capability of Li4SiO4 for absorption CO2 was investigated using the thermobalance instrument. The crystal structure and surface morphologies of the Li4SiO4were also analyzed by X-ray diffraction, SEM. The results showed: the absorption reaction is fast in the temperature range 600～720 ℃, the maximum absorption rate (w) was 29.16% ; and the desorption reaction began in 750 ℃, then Li4SiO4 is regenerated. The concentrations of CO2 obviously affect on the absorption speed and the maximum absorption rate; but the flow rate of CO2 little influences the absorption capability.     

超临界CO2的溶剂特性对脂肪酶催化反应的影响

分别用溶解度参数和介电常数表征超临界流体的溶剂特性，并计算了不同压力下二氧化碳的溶解度参数和介电常数。测定了不同压力下脂肪酶催化月桂酸和正丁醇酯化反应的最大反应速率和米氏常数，研究了溶解度参数δ和介电常数ε对最大反应速率Ｖｍ的影响，并比较好地进行了关联：ｌｎ［Ｖｍａｘ／（ｍｍｏｌｈ－１ｇ－１）］＝４．４６５－０．１５３（δ／ＭＰａ０．５），ｌｎ［Ｖｍａｘ／（ｍｍｏｌｈ－１ｇ－１）］＝４．１８７－８．３１８（ε－１）／（ε＋１）．从而通过溶剂特性将压力这一操作条件直接与反应动力学相联系。     

高温合金冶炼过程中泡沫陶瓷过滤器的作用

使用Ｘ射线衍射仪，ＭＡＡＳ自动图像仪及气体分析，对１（美国ＨＩＴＥＣ公司产）过滤器与２（昌平产ＺｒＯ２基泡沫）过滤器在高温合金冶炼过程中的过滤效果及其组织结构变化进行对比分析，研究结果表明，２种过滤器对钢中氧化物夹杂均有显著去除效果，并且过滤器的组织结构会对其高温性能，冲击性能及过滤作用产生一定的影响。     

陶瓷过滤器脉冲反吹过程中流动参数的测量与分析

在由三根陶瓷滤管组成的过滤器实验装置上，采用压电式压力传感器和热线风速仪分别测定了脉冲反吹过程中滤管内、外动态压力和滤管外瞬态流场。实验结果表明，在脉冲反吹即将终止而过滤过程尚未开始的过渡过程中，滤管内存在严重的低压区，滤管外存在较大的回流区，此时部分原已离开滤管壁的粉尘重新沉降在滤管壁上甚至穿嵌于滤管壁内，严重妨碍了刚性陶瓷过滤器的长周期稳定运行     

纳米TiO2的相变及锐钛矿晶粒生长

通过TiCl     

铁电陶瓷材料实验研究及应用

介绍了压电晶体材料和热释电晶体的极化强度与外电场的线性关系。并通过检测设备(电桥、示波仪、数字表)验证了线性电介质和铁电晶体是典型的非线性电介质外,其极电强度与外电场的关系呈非线性。特别是在具体温度范围内具有自发极化,而且共自发极化强度在电场中与电场强度有常规的电滞回线的形式     

高介、低损耗Ba(Ti,Zr)O_3基电容器陶瓷的研究

采用正交设计实验法研究了配方对Ba(Ti,Zr)O3(BTZ)基电容器陶瓷介电性能的影响 ,得到了影响BTZ基陶瓷介电性能的主次因素 ,各因素水平影响其性能的趋势 对介电常数而言 ,主次影响因素的顺序为Nb2 O5、BaZrO3/BaTiO3、ZnO、CeO2 ;对介质损耗而言 ,主次影响因素的顺序为Nb2 O5、ZnO、CeO2 、BaZrO3/BaTiO3 同时得到了介电常数最大的配方和介质损耗最小的配方 通过正交设计实验得到了综合性能最佳的BTZ基陶瓷 ,它具有高介 (ε)≥1 32 0 0低损耗 (tanδ) <60× 1 0 - 4 和高耐压 (大于 5MV/m) 探讨了各组分对BTZ基陶瓷介电性能影响机理 ,为研制高介、低损耗、高耐压电容器陶瓷提供依据