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101.
Application of the Box-Wilson experimental design method for the spherical oil agglomeration of coal
Yakup Cebeci 《Fuel》2006,85(3):289-297
In this study, the Box-Wilson statistical experimental design method was employed to evaluate the effects of important variables such as bridging liquid (oil) concentration, salt (CaCl2·2H2O) concentration and stirring speed on the agglomeration of bituminous coal. Response function coefficients were determined by the regression analysis of experimental data and the predictions were found to be in good agreement with the experimental results. The optimum kerosene concentration, CaCl2·2H2O concentration and stirring speed were determined as 30 wt%, 1 M and 1683 rpm, respectively, when considering combustible recovery and ash content.In addition, contact angle and solution surface tension measurements were carried out to evaluate of agglomeration success with the contact angle values and surface tension values. The surface tension of CaCl2 2H2O solutions and the average contact angle increased with increasing CaCl2·2H2O concentration. 相似文献
102.
化工企业对环境的影响较大,其制造的化工产品严重威胁着人们的健康。近年来,随着化工企业的规模越来越大,其带来的环境污染问题也越来越严峻。就工业喷漆对环境污染的状况和治理措施进行了分析、探究。 相似文献
103.
区域经济转型和产业结构升级使人才需求发生了变化。以无锡城市职业技术学院计算机专业为例,对计算机类专业人才培养目标、专业结构的调整、模块化课程体系、教师队伍建设,以及校企合作模式的优化等进行了研究,以期形成适应产业结构升级的人才培养模式。 相似文献
104.
Zhen-Yan Deng Jian-Feng Yang Yoshihisa Beppu Motohide Ando Tatsuki Ohji 《Journal of the American Ceramic Society》2002,85(8):1961-1965
Porous ZrO2 ceramics were fabricated by compacting a fine ZrO2 powder, followed by pressureless sintering. Two unidirectional pressures of 30 and 75 MPa were used to prepare the green compacts. The strength and the fracture toughness of porous ZrO2 specimens sintered from the compacts prepared by 75 MPa were substantially higher than those by 30 MPa, especially for the specimens with low porosity. However, the corresponding Young's moduli were identical. This caused the strain to failure of these porous bodies to increase significantly with increasing compaction pressure. Microstructural analyses showed that a number of voids and small flaws existed in the green compacts prepared by the lower pressure, due to the agglomeration of fine ZrO2 grains. It was revealed that the ZrO2 agglomeration resulted in a localized nonuniform shrinkage and degraded the mechanical properties of porous ZrO2 ceramics. 相似文献
105.
在全面分析立窑生产固有问题及立窑企业建设新型千法生产线有利条件的基础上,介绍了技术成熟的2500t/d和5000t/d熟料生产线的主要技经指标、技术方案和主机配置方案;同时就立窑企业建设新型干法水泥生产线要注意的问题进行警示。随着行业发展和技术进步,立窑企业只有走新型干法生产的道路才符合产业政策和企业的长远效益。 相似文献
106.
The different melting temperatures of N‐methyl morpholine N‐oxide (NMMO) hydrates in the cellulose–NMMO hydrate solution may be explained by the rather different crystal structures of NMMO hydrates, which are determined by the amount of the hydrates. The preparative process of cellulose–NMMO hydrate solution may result in cellulose structural change from cellulose I to cellulose II, depending on the amount of the hydrate. Mixtures of cellulose and NMMO hydrate in a blender was changed from the granules to slurry with increasing mixing time at 60–70°C, which is below the melting point of the NMMO hydrate. In the case of 15 wt % cellulose–NMMO hydrate granules, which were made by mixing for 20 min, the melting points of various NMMO hydrates were obtained as 77.8°C (n = 0.83), 70.2°C (n = 0.97), and 69.7°C (n = 1.23), respectively, depending on the hydrate number. However, the melting points of cellulose–NMMO hydrate slurry and solution were shifted lower than those of cellulose granules, while the mixing time of slurry and solution are 25 and 35 min, respectively. These melting behaviors indicate instantaneous liquefaction of the NMMO hydrate and the diffusion of the NMMO hydrate into cellulose during mixing in a blender. When cellulose was completely dissolved in NMMO hydrate, the crystal structure of cellulose showed only cellulose II structure. In the cellulose–NMMO products of granules or slurry obtained by high‐speed mixing, which is a new preparation method, they still retained the original cellulose I structure. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1687–1697, 2004 相似文献
107.
108.
The possibility of multiplicity in an isothermal continuous mixed suspension-mixed product removal crystallizer is explored using the bifurcation theory.A process involving agglomeration controlled precipitation is considered in which secondary nucleation occurs simultaneously with primary nucleation.The determinant equations for the existence of multiple steady states are developed and the multiplicity boundaries dependent on the physical and kinetic properties and operational parameters of the process are obtained by resolving these determinant equations.The number of steady states in the precipitator for various multiplicity regions is determined and the linear stability of these steady states is analyzed by using the Routh criterion. 相似文献
109.
创新集群管理信息化目前依然是一个较新的课题, 不同产业、不同区域都在摸索当中。本项目基于创新集群科研管理信息化的需求, 针对创新集群跨机构、跨区域、跨领域的特征, 利用先进的信息化技术和应用平台, 通过统一的门户管理平台, 在创新集群内部建立功能互补、交流合作、协同发展的综合管理生态系统, 有效集成、共享优势创新资源, 实现集群内部资源的灵活组合和调配, 不断促进跨所跨学科的交叉融合和协同发展, 提升创新集群的管理能力和综合竞争力。 相似文献
110.
概述了中国化学纤维工业的现状和今后的发展方向.着重介绍了中国产业用纺织品的原料、产品开发方向及其主要类别的应用情况. 相似文献