共查询到20条相似文献,搜索用时 109 毫秒
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针对热电厂锅炉给水泵出口段及平衡机构汽蚀腐蚀现象,分析故障产生原因,在总结检修处理方案的基础上,通过对平衡套密封结构进行改造,采取多级复合密封,彻底解决泄漏引起的汽蚀腐蚀问题。 相似文献
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《Dyes and Pigments》1987,8(2):119-127
Dyes whose acid and base forms are differently coloured from each other have the possibility of showing thermochromism based on the temperature dependence of the acid-base equilibrium. To clarify such character of the dyes, the temperature dependence of the acid-base equilibrium and the colour change have been investigated using 1-hydroxyanthraquinones and phthaleins. 1-Hydroxyanthraquinones in solution of sodium acetate showed such a colour change, i.e. yellow at lower temperature and orange at higher temperature. This colour change was due to the larger temperature dependence of their acidity than that of the basicity of the medium. In solution of triethylamine, on the other hand, the reverse colour change was observed because the temperature dependence of their acidity is smaller than that of the basicity of the medium. Similar thermochromic character of the phthaleins was also investigated. 相似文献
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H. Y. F. El-Baradie M. A. Khattab R. M. Issa J. Y. Maghrabi 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1983,33(3):123-129
The u.v. and i.r. spectra of some arylidene derivatives of salicylic hydrazide have been studied. The u.v. spectra in organic solvents are considered in terms of medium effect and molecular structure. The changes of the spectra in buffer solutions are explained on the basis of the shifts in the acid-base equilibrium set; the various pK values are determined and commented upon in relation to substituent effects. The main bands in the i.r. spectra are assigned and the shift in their positions is discussed in the light of substituent effects. 相似文献
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Isomerization is used in refining industry to upgrade gasoline. Since it is an important process, it is desirable to analyze the reactions that take place in the process. In this paper, the isomerization of a mixture of hydrocarbons was modeled by solving the chemical equilibrium of the system. A direct application of the chemical equilibrium solution cannot reproduce experimental results. However, when some of the system reactions are molar extent limited, the solution can reproduce published experimental data. 相似文献
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对聚合物溶液在多釜凝聚过程的聚合物-溶剂-水多相体系的相平衡研究表明,当聚合物浓度为20%—30%(体积)时,可将聚合物溶液近似作为纯溶剂处理;聚合物种类对相平衡基本无影响。以稀土异戊橡胶的凝聚为例,建立了等速凝聚阶段和减速凝聚阶段的动力学模型。 相似文献
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K_2B_4O_7-K_2SO_4-KCl-H_2O四元体系298K相平衡研究 总被引:2,自引:0,他引:2
采用等温溶解平衡法研究了四元体系K2B4O7-K2SO4-KC l-H2O在298 K的相平衡及平衡液相,测定了平衡液相的溶解度及密度。研究结果表明:该四元体系为简单共饱和型,无复盐及固溶体形成。根据实验数据绘制了相应的相图。相图中有1个共饱点E,3条单变曲线E1E,E2E和E3E;3个结晶区平衡固相分别为:K2B4O7.4H2O,K2SO4和KC l,并简要讨论了密度变化规律。实验结果表明,KC l对K2B4O7.4H2O和K2SO4有盐析作用。 相似文献