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81.
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83.
The purpose of this work is to study the kinetics of the esterification of maleic anhydride with methanol to form dimethyl maleate in a batch reactor in the presence of H-Y zeolite as a catalyst. This is a series-parallel type multiple reaction where, the first reaction involves the formation of monomethyl maleate that further reacts with alcohol to form dimethyl maleate. Dimethyl maleate was found to be the only product in the reaction mixture. Temperature, speed of agitation, catalyst size, reactant mole ratio and catalyst loading have pronounced effect on the rate of the reaction. A homogeneous rate model and heterogeneous rate models have been derived and fitted with the experimental data. The activation energy was found to be 44.65 kJ/mol.  相似文献   
84.
The aim of this paper is to investigate magneto-thermo-viscoelastic surface waves in electrically and thermally conducting layers involving time rates of strain and stress of ordern, the media being under an initial stress in the nature of hydrostatic tension or compression. The theory of magneto-thermo-visco-elastic surface waves in the conducting medium involving strain rate and stress rate ofnth order is derived under initial stress. This theory is then employed to obtain wave velocity equations in specific cases. Results obtained in the above cases reduce to well-known classical results when additional fields are absent.  相似文献   
85.
Best estimate accident analysis with uncertainty evaluation is being encouraged in the present licensing scenarios of nuclear power plants. This paper deals with uncertainty and sensitivity analysis for station blackout in PSB VVER integral test facility under the framework of coordinated research project of IAEA. Nodalization was developed using best estimate system code RELAP5/MOD3.2 and its steady state and transient level qualifications are achieved. Sampling based approaches are used to carry out uncertainty and sensitivity/importance analysis. The objective of the analysis is to get confidence for uncertainty methodology by comparing with the experimental results and extend its applicability to NPPs. Uncertainty analysis is carried out by selecting nine important input parameters with specified ranges and its uniform distributions. A design matrix of 45 × 9 is generated for variations of input parameters with the Latin Hypercube Sampling and 45 code runs were taken. Linear regression was also carried out to quantify the effect of each individual input parameter on output parameters in terms of standard rank regression coefficients. Uncertainty band in output parameters is defined between 95th and 5th percentile value. It is observed that most of the experimental values and code calculated reference values are lying within the uncertainty band. For most of the parameters, width of uncertainty band increases with transient progression time.  相似文献   
86.
Emf measurements have been made in cells without liquid junction of the type H2/HX (m1), MXn(m2)/AgCl, Ag . . (I) containing mixtures of HCl and CaCl2 in different proportions, but at constant total ionic strength (I = 2, 1, 0.5). The measurements have been carried out at 5°C intervals over the temperature range 5–35°C. AgAgCl electrodes prepared by two different methods (thermal and thermoelectrolytic) were used of which the thermoelectrolytic electrodes were found to give more consistent results. The results when extrapolated properly lead to E° values at the different temperatures which agree well with those reported in literature. The application of the Pitzer method leads to the calculation of the ionic interaction coefficients α12 and α21, at the different constant ionic strengths. The nature of variation of these α's with the total mixture ionic strength at different temperatures has been considered.  相似文献   
87.
A nutritional study was carried out with white albino rats fed treated and untreated sal meal at 30% level in diet for 3 months. The effect of high protein level in diet on rats fed 30% untreated sal meal was also investigated. rats fed 30% sal meal with intact tannin showed abnormal lipid spectrum and also protein content in both liver and serum while the lipid spectrum and protein content in liver and serum of rats fed 30% treated sal meal were comparable to that of control rats. The toxic effect of sal meal was reduced to some extent when the protein level was improved in diet.  相似文献   
88.
大型水轮发电机组轴系临界转速模拟试验研究   总被引:1,自引:2,他引:1  
针对大型水轮发电机组轴系临界转速难以实际测定的现实问题,从理论分析的角度出发,抓住水力机组轴系结构的基本特点,提出采用较为简单的模拟结构,试验研究水力机组轴系固有频率及其振型特征。初步研究结果已在理论分析和实际机组中得到验证。  相似文献   
89.
A. Sengupta  S. P. Basu  S. Saha 《Lipids》1975,10(1):33-40
The fatty acid composition ofSapindus mukorossi seed oil was determined by spectrophotometry, urea complexation, and gas liquid chromatography (GLC). The percentages of individual acids were found to be: palmitic, 4.0; stearic, 0.2; arachidic, 4.4; oleic 62.8; linoleic, 4.6; linolenic, 1.6; and eicosenoic, 22.4. Triglyceride composition was calculated from the fatty acid compositions of the native oil and of the monoglycerides produced from it by pancreatic lipase hydrolysis. The oil is composed of 0.1, 2.1, 22.0, and 75.8% trisaturated, monounsaturated disaturated, diunsaturated monosaturated, and triunsaturated glycerides, respectively. The special characteristic of theSapindus mukorossi seed oil is its content of 26.3 and 26.7% triolein and eicoseno-di-oleins, respectively.  相似文献   
90.
Fatty acid and triglyceride compositions of the seed oil of Thea sinensis (tea seed oil) of Indian origin have been determined by combination of techniques of low temperature crystallisation, spectrophotometry, pancreatic lipase hydrolysis, thin-layer chromatography, gas–liquid chromatography and densitometry. Percentages of individual fatty acids were found to be: palmitic, 17.8; stearic, 3.0; oleic, 59.9; linoleic, 18.0. Triglyceride composition was calculated from the fatty acid compositions of the native oil and of the monoglycerides produced from it by pancreatic lipase hydrolysis. The oil is composed of 0.7, 11.1, 41.9 and 46.3% GS3, GS2U, GSU2 and GU3 respectively. Prominent features of the oil is its content of 11.6, 21.4 and 22.0% dioleolinolein, triolein and dioleopalmitin respectively.  相似文献   
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