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131.
132.
本文主要从选择卡伦水库实行洪水风险调度的依据、水库洪水控制标准、调度原则及效益等方面论述卡伦水库实行洪水风险调度的重大意义。特别强调在水库洪水调度过程中适度承担风险,必须确保工程安全运行、科学调度,加强管理,依法防洪,合理蓄水,要正确把握水库安全度汛与水资源合理利用的关系,正确处理防洪与兴利的关系,正确处理风险与效益的关系,充分发挥水库的综合效益。适度承担风险进行水库洪水调度,既充分利用雨洪资源,又尽最大可能变水害为水利,实现雨洪资源化,达到人、水与自然和谐共处,促进经济社会协调发展。 相似文献
133.
M.A.K. Lodhi 《Energy Conversion and Management》1996,37(12):1677-1694
Solar ponds are probably the simplest technology available for the useful conversion of solar energy. The basic technology is proven. Solar ponds have been shown to be technically feasible and economically viable for many applications, particularly for thermal use. The electrical conversion and use of solar energy via solar ponds is still questionable, in general, for economic viability. By putting the untapped sources together in the South Plains region, it looks promising economically both for thermal and electrical conversions and applications. There are a number of alkaline lake basins randomly scattered in the South Plains region of the U.S.A. In that area, there are thousands of crude oil producing wells that produce brine in abundance. The selection of suitable alkaline lake basins as a solar pond site and as depository sites of brine from oil wells and the using of this brine and salty water from alkaline lakes makes the solar pond economically viable for both thermal and electrical demands in the area. 相似文献
134.
用于氢化的铜铬氧化物催化剂的研究 总被引:4,自引:0,他引:4
通过铜铬氧化物催化剂用于豆油的选择氢化,研究了制备方法及氢化条件对催化剂活性的影响.在所用的五种催化剂中,以Adkins法制备的催化剂活性最好,碳酸氢铵法次之.文中还对催化剂焙烧气氛、焙烧温度、焙烧时间、铜铬原子比对催化剂活性的影响以及氢化温度、催化剂用量、搅拌速度、氢流速等对反应的影响进行了较详细的讨论. 相似文献
135.
Monitoring water quality in reservoirs with IRS-1A-LISS-I 总被引:1,自引:1,他引:0
V. K. Choubey 《Water Resources Management》1994,8(2):121-136
An attempt has been made to quantify the relationship between the variation in IRS-IA-LISS-I (Indian Remote Sensing Satellite-1A Linear Imaging Self-Scanning System) radiance data and field measured change in secchi disc depth. Secchi disc depth was measured for 47 predetermined sampling locations on reservoir surface water. At extinction depth (secchi depth), water samples were collected from all the sampling locations. Suspended sediments of eight locations representing various reaches of the reservoir were selected for mineralogical, particle size and optical properties analysis. The LISS-I radiance value in band 1 (0.45–0.52µm) band 2 (0-52–0.59 µm) and band 3 (0.62–0.68 µm) were used in a regression analysis. The absorption infrared band 4 (0.77–0.86 µm) was not included in the analysis. In these, the dependable variable was secchi depth (SD) and the LISS-I-radiance data was the estimator variable. Forty-seven data sets of 20 October 1988 from Tawa reservoir surface water were used to obtain an estimator equation for SD. The verification of the estimator equation was tested by applying it to a data set of 21 measurements of 28 September 1988 for this reservoir. The coefficient of correlation between observed and estimated values for the 28 September 1988 data set wasr=0.92 for SD, indicating that the equation could accurately predict the water clarity (SD) for this reservoir on new occasions from IRS-IA-LISS-I spectral data. It is shown that mineral composition and optical properties of suspended sediments influence the reflected radiance of water quality. It is concluded that IRS-IA-LISS-I data provide a useful means of mapping water quality in reservoir. 相似文献
136.
百色盆地林蓬油藏为一浅、薄、低产、低渗的普通稠油构造油藏。通过对油藏特征、原油热物性、热采数值模拟初步分析及热米开发经济效益的初步评价,认为林蓬油藏利用我国现有的热采技术投入开发具有可行性,并提出了具体实施方案和工作意见. 相似文献
137.
文中着重阐述了上马水库库坝区的地裂缝产生的原因及发育规律,分析了地裂缝对水库的直接危害,为水库除险加固设计提供了指导,并提出了切实可行的工程处理措施建议。 相似文献
138.
In new institutional economics, the variance in institutions explains differences in cross-country output per capita. Institutions may also explain how the supply of oil is affected within oil-producing countries. For example in the early 1970s, as nominal oil prices increased from $3 per barrel to $11 per barrel, a number of OPEC oil producers changed the institutional environment by nationalizing their oil production and putting under government control all petroleum-related capital and infrastructure. This affected oil supplies. Similar institutional changes may be happening again now that oil prices are rising. In particular, the newly democratic Russia may be following the same path. The Russian government has already effectively taken over control of much of the oil production capacity in the country and is still heavily involved in natural gas production. In this paper, we will look at the Russian upstream oil industry as it changed from central planning to a market-oriented sector and is now swaying toward re-nationalization. Some of the laws and institutional transitions will be detailed in order to elucidate what has taken place. 相似文献
139.
针对江苏沙埝低渗透油藏的地质特征,对沙埝低渗储层压裂改造后影响产能的主要因素从储层地质条件和压裂施工技术优化两大方面进行了阐述和评价,提出了适合于沙埝低渗透储层改造的选井选层地质条件及优化方案并对今后压裂改造的方向提出了新思路。 相似文献
140.
������ظ���½��������ز�ˮ�����о� 总被引:4,自引:0,他引:4
位于准噶尔盆地腹部的陆梁油气田是准噶尔盆地的又一个亿吨级油气田。笔者运用地球化学方法分析了陆梁油气田石炭纪—早白垩世地层水的类型、平面和纵向分布特征,将其划分为3个水文地质旋回,第一旋回为石炭系—三叠系,为深层静止开放的滞流型水力系统;第二旋回为侏罗系八道湾组—西山窑组,为中层弱开放的压实驱动型水力系统;第三旋回为侏罗系头屯河组—白垩系,为浅层强开放的重力驱动型水力系统。第一、二水文地质旋回是油气生成和初次运移的有利时期,淋滤期前的一段时间是油气二次运移和成藏的较好时期,第三水文地质旋回是油气藏破坏及次生油气藏形成的时期。 相似文献