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排序方式: 共有3038条查询结果,搜索用时 15 毫秒
1.
Lindsey Yue Alicia Bayon Wojciech Lipiński 《American Institute of Chemical Engineers》2021,67(8):e17267
The effects of particle size and carbon dioxide concentration on chemical conversion in engineered spherical particles undergoing calcium oxide looping are investigated. Particles are thermochemically cycled in a furnace under different carbon dioxide concentrations. Changes in composition due to chemical reactions are measured using thermogravimetric analysis. Gas composition at the furnace exit is evaluated with mass spectroscopy. A numerical model of thermal transport phenomena developed previously is adapted to match the physical system investigated in the present study. The model is used to elucidate effects of reacting medium characteristics on particle temperature and reaction extent. Experimental and numerical results show that (1) an increase in particle size results in a decrease in carbonation extent, and (2) the carbonation step consists of fast and slow reaction regimes. The reaction rates in the fast and slow carbonation regimes increase with increasing carbon dioxide concentration. The effect of carbon dioxide concentration and the distinction between the fast and slow regimes become more pronounced with increasing particle size. 相似文献
2.
集中药包与条形药包爆破漏斗及抛掷堆积研究 总被引:10,自引:4,他引:6
把集中药包拉成条形药包之后,其爆破漏斗变化有多大?条形药包能否改善抛掷堆积?可否用集中药包的爆破漏斗参数(n、R、R’、P)及经验方法来设计条形药包的爆破漏斗?本试验研究将回答这些问题。 相似文献
3.
Aimin Xiang Zhongjie Du Qinghua Zeng Chen Zhang Hangquan Li 《Polymer International》2005,54(10):1366-1370
This paper presents recent efforts on the preparation of flexible polyhedral particles via concentrated emulsion templating polymerization in which the hydrophilic monomer (acrylamide) and hydrophobic monomer (butyl acrylate) are polymerized simultaneously in the continuous and dispersed phase, respectively. Such templating polymerization has been enhanced in our systems owing to the introduction of acrylamide monomer and their higher polymerization rate in continuous phase as compared with butyl acrylate in dispersed phase. Diffusion between the different phases was also inhibited. Furthermore, the stability of the concentrated emulsion and the molecular weight of the produced poly(butyl acrylate) were found to be significantly affected by the amount of redox initiator. The morphology of the particles could be controlled by varying the volume fraction of the dispersed phase and the polyhedral particles were achieved at higher volume fraction. Copyright © 2005 Society of Chemical Industry 相似文献
4.
The ennoblement of corrosion potential (Ecorr) of passive metal immersed in seawater was investigated with electrochemical technology and epifluorescence microscopy. The in situ observation showed that the bacteria number increased on the metal surface according to an exponential law which was in the same way with the ennoblement of Ecorr. At the same time, the anodic polarization current of high‐Mo stainless steel decreased in the initial days. According to the mix‐potential theory and the characteristics of polarization curves of high‐Mo steel in natural seawater, the ennoblement of corrosion potential may be induced by the decrease of the passive current density. 相似文献
5.
针对企业集团分权化管理的缺点,设计出一套利用互联网络技术实现企业集团财务集中控制的模式,给出了模式的图示及说明。 相似文献
6.
Boyka K. Doytcheva 《加拿大化工杂志》2003,81(2):285-288
The author suggests a technological approach relevant to the optimization of toothpaste compositions with regard to the easy release of the therapeutic ingredients under shear deformation. It is based on the comparative assessment of the steady‐state viscous behaviour of placebo samples (mixtures containing all the components except the therapeutic ingredients) and the final products. It is presumed that the maximum beneficial effect of the toothpastes, as therapeutic agents, is achieved if the final products and the placebo blends display similar shear‐thinning characteristics. 相似文献
7.
I. A. Fatile 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(2):94-100
The effect of yeast cell volumetric concentration on the rheological properties of the suspensions was measured in a pipe-flow viscometer at 30°C: at low microbial concentrations the suspensions were Newtonian; however, non-Newtonian behaviour, which could be described by the power-law equation, was observed with suspensions at high microbial volumetric concentrations. At conditions of constant microbial morphology and growth rate, the results also indicated that a relationship could be developed between the power-law constants and the microbial volumetric concentration. 相似文献
8.
9.
Local-strain and linear-elastic fracture-mechanics (LEFM) methodologies have been investigated for prediction of the corrosion-fatigue
life of notched components of specially developed Al-2.5Mg alloys exposed to Arabian Gulf seawater environment. Corrosion-fatigue
crack initiation life estimates were obtained using strain-life relationships; corrosion-fatigue crack propagation life estimates
were obtained using LEFM relationships. The total corrosion-fatigue life was considered to be the sum of the crack initiation
and crack propagation lives. Estimated corrosion-fatigue lives were compared with experimentally obtained corrosion-fatigue
life data using center-notched specimens of three types of Al-2.5Mg alloys (containing different amounts of chromium) exposed
to Arabian Gulf seawater environment. Two notch geometries, a circular notch (K
t= 2.42) and an elliptical notch (K
t= 4.2), were investigated. Good corrosion-fatigue life predictions can be obtained using local-strain and LEFM methodologies
by determining the relevant material constants via a few simple fatigue tests on smooth specimens and a few crack-growth-rate
tests in the environment at the frequency of interest. 相似文献
10.
简要介绍淮化集团浓硝酸生产工艺,通过对热发烟硝酸生产的关键设备高压釜的进料管,筛板的改造,增加氧气压力,提高N2O4纯度等工艺调整,使高压釜的生产能力由原设计的12.8t热酸/h增加到38.6t热酸/h。 相似文献