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31.
There have been extensive attempts in recent years to perform spatial equilibrium analysis of commodity markets, particularly that of energy. Most of these attempts have been based on linear programming transportation models, and more recently quadratic programming models. Unfortunately, neither of these modelling approaches can deal with the case of multi-commodity analysis with non-symmetric regression coefficients. In this paper, we overcome this problem by employing the linear complementarity programming model. In addition, we show how the model can be applied to coal and gas energy flows within a single region. Future potential applications of the model are also implied. 相似文献
32.
The attack of nickel, cobalt, iron, and alloys of these metals containing chromium and aluminum, by gases containing sulfur-oxygen,
carbon-oxygen, and nitrogen-oxygen has been studied at temperatures of 600 and 900°C. The degradation of these metals and
alloys was characterized by using standard analytical techniques with emphasis on optical metallography. Three types of accelerated
degradation were identified for the attack of alloys by gases containing another oxidant in addition to oxygen. One type of
degradation occurred because of the formation of reaction products composed of mixtures of phases involving both of the oxidants.
Another type resulted from the reaction of second oxidant phases with oxygen. The third form of degradation involved the development
of less protective phases due to thermodynamic instabilities. Thermodynamic stability diagrams are used to help account for
the effects produced by different elements in the alloys. 相似文献
33.
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35.
The solubility parameter of poly(ethylene oxide) at 25°C has been determined using the method developed by DiPaola-Baranyi and Guillet, by the extrapolation of the values of the interaction parameter χ, at high temperatures, ranging from 70°–90°, 90°–110° and 110°–130°C down to 25°C. The values of the solubility parameter obtained, depending on the temperature ranges employed, are 9.8, 9.9 and 10.1, respectively. 相似文献
36.
二氯苯系列产物的气相色谱分析 总被引:4,自引:0,他引:4
介绍了在相同条件下分析对二氯苯、邻二氯苯、间二氯苯、1,2,4-三氯苯和氯化苯的气相色谱法。该法采用灵敏度为10^8的1002气相色谱仪或其它类似色谱仪、氢火焰离子化检测器,在选择有机皂土和己二酸乙二醇酯混合固定相(有机皂土:6201担体=5:100;己二酸乙二醇酯:6201担体=5:100)的质量比为(1.6~1.7):1时,能够有效地分离上述几种组分,从而可以对上述组分进行同时分析。其检出限在10^-6~10^-7之间,线性范围在10^-6~10^-3之间,便于产品检验和环境监测。 相似文献
37.
Effect of additives on formation of natural gas hydrate 总被引:1,自引:0,他引:1
The formation of natural gas hydrate (NGH) is studied in this work. Kinetics data of hydrate formation with no agitation were collected at various concentrations of the aqueous solutions with different additives such as alkylpolyglucside, sodium dodecyl benzene sulfonate and potassium oxalate monohydrate. Various kinds of additive increased the formation rates of NGH and its storage capacity and reduced the induction time of NGH formation. Moreover, the storage capacity, the induction time and the hydrate formation rate were influenced by the concentration of the aqueous solution. 相似文献
38.
The relationship between chemical structure and reactivity for thermal hydroprocessing was studied for five gas oils derived from Alberta bitumens. Chemical structure was characterized by combining data from 1 H and 13 C nuclear magnetic resonance spectroscopy, class fractionation, and elemental analysis to calculate structural parameters. Thermal hydrotreating was performed in a continuous-flow stirred reactor at 420 and 440°C, 13.9 MPa hydrogen pressure, and 1.5 h1 LHSV. Conversion of the 343–525°C boiling fraction of the gas oils was correlated with the concentration of naphthenic methylene groups in the feed. Formation of methane and ethane was dependent on the degree of condensation of the aromatic rings in the feed oils. Thermal desulfurization was highly correlated with the amount of saturates in the feed, and the aromaticity of the resin fraction. Hydrogen consumption increased with the aromaticity of the gas oil… 相似文献
39.
40.
对动态泡沫床处理过磷酸钙含氟尾气的有关技术及费用作了说明 ,指出该方法费用高 ;提出一种新方法 ,该方法不加任何化学助剂 ,采用水作吸收剂 ,只需改变动态泡沫床一些设计参数和选用一种特殊的喷头 (喷头周围设计 1个圆锥形死角区 ,使含氟气体不可能进入该区 )避免了硅胶堵塞。该方法已在湖南浦市化工总厂运行 1年多未发现堵塞 ,同时该法投资少、能耗低、排放尾气达标 相似文献