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41.
本文首次将统计热力学的Weeks-Chandler-Anderson(简称WCA)微扰理论应用于非极性液体定容比热容和定压比热容的推算,用一些液体的p-v-T实验数据拟合了理论中所用LJ势能函数的势能参数,并提出一个通用关联式。本文方法具有通用性,在编制的计算程序中只需输入物质的临界温度、临界比容、偏心因子等就能算出相应的比热容,工程应用十分方便。  相似文献   
42.
以流化床应用为代表的气固流动系统是许多化工过程中的重要组成部分 ,CFD( computational fluid dynamics)方法能够为其优化设计和放大提供所需要的信息 .本文采用双欧拉模型 ,与 Gidaspow等的实验结果进行了对比 ,模拟了二维射流流化床内气泡的形成规律 ,得到了带锥型分布器的流化床内瞬时空隙率和气固相速度分布等流体力学参数 .对锥型分布器流化床的实验结果表明 ,模拟得到的气泡的形状与实验现象相接近 .  相似文献   
43.
The disposal and re-use of spent bleaching clay from the vegetable oil processing industry is a problem of growing importance. Although today the only practical way of removal of the spent material is disposal, extraction with organic solvents is a well-known method of de-oiling contaminated bleaching clay. In our investigations we compare the extractibility of two different types of bleaching clays with CO2 as a solvent. All experiments were carried out with a high-pressure extraction plant. The extraction and separation conditions, temperature and pressure, as well as the CO2 mass flow, were varied during experiments. The aim of our investigations was a complete separation of the oil from the adsorbent. The latter should then be re-used as bleaching clay. The oil and the bleaching clay were analyzed and tested, respectively. The results show that oil of good quality can be recovered and the bleaching clay still has an activity approximately 50% of fresh clay.  相似文献   
44.
A supercritical fluid extraction method has been applied to test the feasibility of tocopherol concentration from soybean sludge with carbon dioxide at temperatures and pressures ranging from 35 to 70°C and 200 to 400 bar, respectively. The supercritical solubility of the esterified soybean sludge was over 4–6 times greater than that of the original soybean sludge. By a simple batch-type one-stage method the tocopherols in the esterified soybean sludge could be concentrated up to 40 wt%. The overall results of the present study show that soybean sludge initially containing about 13–14 wt% tocopherols may require a countercurrent multistage column to be highly and effectively concentrated.  相似文献   
45.
电解法处理利福霉素SV钠废渣分离液的研究   总被引:2,自引:0,他引:2  
刘瑛  王娉 《工业水处理》2002,22(2):30-31
根据电化学原理,采用电解法,利用铁屑与炭粒作电极,处理利福霉素SV钠药渣分离液,讨论各种因素对分离液污染物作效果的影响,COD去除率可达91.8%左右,脱色率可达95%左右。  相似文献   
46.
陈怡 《贵州化工》2003,28(6):21-22
介绍了合成型机动车制动液的生产和配方,讨论了物料组成对产品的影响。  相似文献   
47.
The process of grinding soybeans to a fine flour and extracting the flour with hexane was studied on a pilot plant scale. The crude oil from the pilot plant study had 15 ppm phosphorus and was suitable for physical refining after a light acid pretreatment and bleaching. The refined oil showed a Lovibond color of 1.4 yellow and 0.3 red. The pilot plant study also showed that grinding of the soybeans and the separation of solid from miscella were the most difficult steps in solvent extraction with fine flour. A laboratory study on separation of miscella from meal by aqueous ethanol reduced the hold-up volume, but it did not remove all the miscella. A test with betacarotene showed that only the miscella outside the flour particles was displaced. Aqueous ethanol solutions used as a second solvent extracted additional nontriglyceride materials (primarily phospholipids) from the meal. Also, the free fatty acid content of the oil was increased with aqueous ethanol solution wash. The quality of the extracted crude oil was lowered by using a second solvent, but it had the advantage of needing only one centrifugation to separate miscella from meal.  相似文献   
48.
Jeffrey A Galloway 《Polymer》2004,45(2):423-428
The effect of sample size on the results of solvent extraction measurements for detecting cocontinuity in polymer blends was investigated. Poly(ethylene oxide)/polystyrene (PEO/PS) blend samples of several thicknesses were analyzed by removing the PEO phase using water extraction. The experimental degree of continuity was shown to have a linear dependence on the reciprocal of sample thickness. A model is proposed to explain this dependence and to allow the bulk or true degree of continuity to be determined. Measurement of the bulk degree of continuity is useful for understanding properties of cocontinuous polymer blends such as electrical conductivity, impact strength, or tensile strength.  相似文献   
49.
介绍研制的题示混合器结构及其混合机理。在分析球窝流场各节点速度分布的基础上,用加权平均总应变和分流混合度作为评定指标,对球窝型混合器的混合行为进行分析。通过对比实验证明球窝型混合器对于高粘流体具有良好的混合功效。  相似文献   
50.
Microcellular foaming of biodegradable Bionolle in supercritical CO2 has been produced. The effects of a series of variable factors, such as saturation temperature, saturation pressure, and depressurization time and step on the foam structures and density, were studied through measurement of density and SEM observation. The experimental results show that higher saturation temperatures lead to an increase in bulk densities; and different depressurization time and step result in different product cell morphology. In addition, at some saturation temperature, the orientation of the cells can be found in the product morphology. XRD experimental results show that the foaming treatment with SC CO2 increased the crystallinity of Bionolle. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2901–2906, 2006  相似文献   
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