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71.
潘元伯 《合肥工业大学学报(自然科学版)》1993,(2)
通过对塌陷湖的实地勘查,运用水均衡原理,计算出该湖可供开采的水资源,认为该塌陷湖可作为淮北市供水后备水源地之一。 相似文献
72.
Noncooperative games are used to demonstrate that, while free riding is always an option, the “tragedy of the commons” is not inevitable. When the decision to cooperate or free ride is considered in a dynamic setting, there is no intermediate case where some cooperate and others free ride. The game is only stabilized in either full cooperation or full defection. The important factor in obtaining a cooperative outcome is the critical number of players that decide to cooperate. The concept of commitment is used to demonstrate the necessary and sufficient conditions for full cooperation. Although the analysis is based on a shared water resource, it can be extended to other natural resources with common costs and private benefits, especially in the cases where there are no international authorities or treaties that internalize the externalities involved in privatizing the resource. 相似文献
73.
该文介绍了在Windowe3.1环境下.利用MicrosoftC(++)及其基本类库(MFC)开发光伏水泵报价系统的方法。该方法采用了面向对象技术,使软件具备可重用性。同时,MFC类库的使用使复杂的Win-dows应用程序的编程接口变得更容易。该方法对其它工程报价问题也具借鉴意义。 相似文献
74.
合成丙交酯中微量水分分析 总被引:3,自引:0,他引:3
合成丙交酯中微量水分分析徐溢,柳胜春(重庆大学化工学院分析教研室630044)关键词丙交酯,微量水,定量分析丙交酯是人工合成骨材料聚乳酸的合成中间体,其性能决定着合成产品的品质,要获得高质量的合成材料,对中间体的分析和监测十分重要。一般要求丙交酯中间... 相似文献
75.
The heats of solution at 25°C for a number of hydrocarbon gases are reported as measured by a calorimetric method. There is excellent agreement between the standard enthalpy changes of solution measured calorimetrically and those derived from high precision temperature dependent solubility measurements. However the calorimetrically determined standard enthalpies of solution of a number of gases are greatly improved over values obtained from low precision temperature dependent solubility measurements. A method is presented to readily estimate the standard errors in the standard enthalpy change for any process derived from the temperature dependence of the equilibrium constant for the process. Comparison of the standard enthalpies and entropies of solution of hydrocarbon gases in water shows that the standard free energies of solution for all hydrocarbon gases investigated are dominated by unfavorable entropy contributions. A strong linear correlation between the standard entropy of solution and the number of hydrogens in the hydrocarbon molecule is found. This correlation suggests that the hydrocarbon hydrophobic effect is regulated by the number of allowable configurations of a water molecule in contact with each C–H group. 相似文献
76.
E. U. Franck 《Journal of solution chemistry》1973,2(2-3):339-356
A survey is given of recent experimental results obtained from high-temperature, high-pressure investigations with water, aqueous solutions, and ionic fluids. Data on the static dielectric constant of water to 550°C and 5 kbar are given and discussed with respect to their relation to water structure. Infrared and Raman spectra of HDO in pure water have been obtained to 400°C and 4 kbar, which give information on hydrogen bonding. Xe–H2O and CO2–H2O mixtures were investigated in the infrared. Ni(II) and Cu(II) complexes were investigated by absorption spectroscopy in aqueous solutions of high chloride content to 350°C and 2–6 kbar. The gas-liquid critical point of ammonium chloride was found at 880°C and 1635 bars. This fluid appears to be predominantly ionic even in the critical region. The possibility of converting pure polar fluids such as ammonia and water into concentrated ionic solutions by self-ionization at very high pressures is mentioned.This paper was presented at the symposium, The Physical Chemistry of Aqueous Systems, held at the University of Pittsburgh, Pittsburgh, Pennsylvania, June 12–14, 1972, in honor of the 70th birthday of Professor H. S. Frank. 相似文献
77.
本文介绍一种深井回流充气工艺,它兼具充氧和除铁综合性能的新型工艺形式,能改善含铁地下水的过滤性能.在此基础上提出了深井回流充气稳定期的概念,建立了深井回流充气系统中氧量的平衡关系.通过正交试验,提出了处理中、高量含铁地下水的推荐工艺流程和工艺参数.采用χ—射线衍射方法测试了井内铁泥和成熟滤料表面滤膜的成分和形态,分析了"充气"和"过滤》两过程中的除铁机理. 相似文献
78.
文章针对合肥地区高校教师住房面积普遍偏小,尤其是中青年教师住房十分困难。经过对合肥地区高等院校教师现有住房情况的调研,提出了建造高等院校教师安居园工程的设想及实施方案,对实施“科教兴皖”的战略方针具有现实意义。 相似文献
79.
The characteristics, pattern, hydrodynamic and hydrochemical features, and the movement pattern of the salt waterfresh water
interface of the sea water intrusion and the salt water intrusion, which occur in the coastal area of Laizhou Bay in Shandong
Province, are analysed. The characteristics of the two kinds of intrusion are compared as well. A three-dimensional sea water
intrusion model to describe the sea water intrusion with a transitional zone 1.5–6.0 km wide in the phreatic aquifer and a
solute transport model describing the behavior of cations exchange in the process of sea water intrusion are established. 相似文献
80.