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1.
Nguyen An Tien I. Ya. Mittova O. V. Almjasheva S. A. Kirillova V. V. Gusarov 《Glass Physics and Chemistry》2008,34(6):756-761
Nanocrystalline LaFeO3 is prepared by the dehydration of coprecipitated lanthanum and iron(III) hydroxides. It is shown that the behavior of the samples during heating and the size distribution of LaFeO3 nanocrystals can be considerably different depending on the scheme used for coprecipitation of lanthanum and iron hydroxides; independently of the method employed for coprecipitation of the initial compounds, sintering of the samples at 950°C leads to the formation of lanthanum orthoferrite crystals up to 100 nm in size. 相似文献
2.
We present a numerical study of the packing of uniform spheres under three-dimensional vibration using the discrete element method (DEM), focusing on the effects of vibration condition (amplitude and frequency) and inter-particle frictions (sliding and rolling frictions). The results are analysed in terms of packing density, coordination number (CN), radial distribution function (RDF) and pore structure. It is shown that increasing either the vibration amplitude or frequency causes packing density to increase initially to a maximum and then decrease. Both vibration frequency and amplitude should be considered to characterize the effect of vibration process on packing structure. The sliding and rolling frictions between particles can decrease packing density since they dissipate energy, although the effect of rolling friction is less significant. In line with the change of packing density, microstructural properties such as CN, RDF and pore distribution also change: a looser packing often corresponds to smaller CN, less peaked RDF and larger but more widely distributed pores. 相似文献
3.
镀锌测厚仪 总被引:2,自引:0,他引:2
安福林 《核电子学与探测技术》1997,17(4):288-291
本文叙述了X射线荧光测厚仪的原理、特点及测量头的设计考虑原则。并以我们研制的两种镀锌测得仪为例作了详细说明。 相似文献
4.
本文结合大庆油田天然气矿场加工实际生产装置,讨论了应用HYSIM烃类工艺模拟软件对含有不确定组分的体系进行流程模拟计算的特点、塔设备严格模拟计算过程中输入规定的选择、以及多股流换热器和吸附脱水工艺的模拟计算方法。 相似文献
5.
6.
Guiying Li Ze He Taicheng An Xiangying Zeng Guoying Sheng Jiamo Fu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(7):1019-1026
BACKGROUND: To investigate the microbial degradation performance of organic pollutants in the atmosphere using a biotrickling filter, two microorganism strains, Bacillus cereus S1 and Bacillus cereus S2, were selected, identified and inoculated into a twin biotrickling filter for comparison. RESULTS: Both strains showed good performance towards the degradation of model organic pollutants when gas flow rates ranged from 100 to 600 L h−1. For S1, the total maximum removal efficiency (RE) of toluene was maintained nearly 100% not only at gas flow rates of 100 L h−1 corresponding to empty bed residence time (EBRT) 199.44 s, but also at gas flow rates of 200 L h−1 (EBRT = 99.72 s) and 300 L h−1 (EBRT = 66.48 s). However, S2 had a much lower degradation capability; near 100% removal efficiency was obtained only at the gas flow rate of 100 L h−1 although both bacteria belong to the same Bacillus cereus. With further increase in gas flow rate, the total REs for both S1 and S2 decreased slightly at first and then dropped sharply to 46% and 35%, respectively, at an EBRT of 33.24 s, corresponding to a gas flow rate of 600 L h−1. Starvation for between 2 and 10 days resulted in the re‐acclimation times of both strains ranging between 1.0 and 15.5 h. CONCLUSION: Strain S1 would be a better choice for inoculation into a biotrickling filter than strain S2, because of its much higher toluene removal capacity and rapid recovery to full performance. Copyright © 2008 Society of Chemical Industry 相似文献
7.
在仪表建设安装时期,核电厂核岛仪表管安装属于非常重要的一项内容.基于此,结合实际情况对核电机组仪表管安装质量进行讨论,分析核电建设安装仪表管路期间存在的问题,完善对策,为新建核电机组后期运行奠定坚实基础. 相似文献
8.
D301树脂分离衣康酸的工艺研究 总被引:1,自引:0,他引:1
采用弱碱性阴离子交换树脂D301对发酵法生产的衣康酸进行了分离研究。通过静态交换实验,研究了D301树脂对衣康酸的静态交换动力学,确定了传质机制和影响因素;通过动态交换实验,研究了以硫酸为洗脱剂,以氨水为再生剂的工艺过程,确定了主要工艺参数。 相似文献
9.
Li Yichun General Research Institute For Non-ferrous Metals Beijing China Shao Wenzhu An Xiyun Harbin Institute of Technology Harbin China 《中国有色金属学会会刊》1993,(3)
The process of aging precipitation in SiC_p/6061 and Al_2O_3/6061 composites were investigated. Hardness testing, differential scanning calorimetry(DSC) and transmission electron microscopy were employed. Results showed that the precipitation phase form directly along dislocation lines in the composites because the particles produce high densities of dislocations which makes vacancy densities in the composites decrease, and the main precipitation phase at peak hardness was β′ phase. 相似文献
10.
研究了保温时间和保温温度对电磁搅拌ZL117合金半固态浆料稳定性的影响.试验结果表明:半固态浆料中初生Si的颗粒直径随着保温时间的延长而逐渐增大,但在前15 min内增长速度比较缓慢,15 min后增长较快;随着保温温度的升高而缓慢增大;初生Si的形状系数随着保温时间的延长而变得越来越大,但也在前15 min内变化较为缓慢,15 min后变大速度突然加快;初生Si的形状系数在620 ℃下保温时最小,在610~620 ℃之间随着保温温度的升高而缓慢变小;在620~650 ℃之间随着保温温度的升高而逐渐增加. 相似文献