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191.
Bio-effects of static magnetic fields on cell growth and cell death have been investigated in suspension-cultured tobacco cells as undifferentiated, embryonic plant cell model. The cells in their logarithmic growth phase were exposed to static magnetic field with the magnitudes of 10 mT and 30 mT for 5 h/day. Exposure to static magnetic field ceased the growth and caused an increase in cell death of exposed tobacco cells compared to those cells which were not treated with the field. Promotion of cell death was accompanied by a harmonized increase in the activity of peroxidase and increase of lignifcation of cell walls.  相似文献   
192.
ABSTRACT: Accurately estimating the price elasticity of demand for irrigation electricity is important to major electricity suppliers such as the Bonneville Power Administration (BPA) of the Pacific Northwest. The BPA has a revenue maximization objective, and the elasticity of demand is central to its rate setting process. Several studies have attempted to estimate demand for irrigation electricity, but none has explicitly included federal agricultural policy and program variables. Tins paper discusses how agricultural programs may influence farmers irrigation decisions and thus their demand for irrigation electricity. It suggests that existing programs serve to make farmers more responsive to electricity rate increases than would otherwise be the case. Thus, studies that fail to include them may underestimate the responsiveness of farmers to electricity rate increases.  相似文献   
193.
本文首先研究股票市场影响消费需求的综合效应;在此基础上对中国股票市场促进消费需求的条件和障碍进行分析,并提出了发展股票市场促进消费需求的几条对策.  相似文献   
194.
Access to water for domestic and irrigation uses remains limited across Sub-Saharan Africa, particularly in rural areas. While the technical feasibility of implementing innovative technologies to improve water supply has been often evaluated, less is known about the drivers that motivate users to pay for obtaining the inherent benefits of improved water supply. In this article, the determinants of the marginal willingness to pay (mWTP) for improved domestic and irrigation water are investigated. For this purpose, a contingent valuation study is performed in rural Rwanda. This study uses survey data from 316 households situated in 8 villages, in which ~20% of the households receive electricity thanks to microgrids powered by solar energy. It is found that the mWTP for improved domestic water supply is influenced by the proportion of children in the household, business ownership, and satisfaction with water quantity and quality. The mWTP for irrigation is determined by respondent education, business ownership and crop area planted. This paper contributes to the literature by allowing a comparison of the determinants of the mWTP for improved domestic water supply to the determinants of the mWTP for irrigation. Another contribution is to examine the mWTP for improved water infrastructure in partially electrified villages. Identifying areas with high marginal benefits from water can guide infrastructure investment and electrification efforts while improving well-being and increasing revenues in rural areas.  相似文献   
195.
金矿床黄铁矿热电性质形成机理实验研究及其找矿应用   总被引:1,自引:0,他引:1  
近年来采用黄铁矿热电性质特征寻找内生金矿床取得很大进展,但在具体矿床 应用中,不同学者有不同认识和结论。作者通过实验矿物学的研究方法,模拟金矿床形成的物 理化学条件,实验合成各种特征的黄铁矿晶体,深入探讨黄铁矿形成时物理化学条件对黄铁矿 的化学组成及热电性质的影响程度。论述黄铁矿热电性质及其矿物的铁硫比值及As、Co、Ni含 量变化的演变规律,对利用黄铁矿热电性质找金应用进行综合评述。  相似文献   
196.
用甲苯直接萃取酸化后尿中的除草醚,以气相色谱法测定。方法的最低检测限为2μl/l;精密度为4.7%;回收率为95%。  相似文献   
197.
Renewable generating technologies offer an effective means for climate change mitigation. Policy makers, however, are wary because of the widespread perception that these technologies cost more than conventional alternatives so that increasing their deployment will raise overall electricity generating costs. Energy planning represents an investment-decision problem. Investors commonly evaluate such problems using portfolio theory to manage risk and maximize portfolio performance under a variety of unpredictable economic outcomes. Energy planners need to similarly abandon their reliance on traditional, “least-cost” stand-alone kWh generating cost measures and instead evaluate conventional and renewable energy sources on the basis of their portfolio cost – their cost contribution relative to their risk contribution to a mix of generating assets. Energy security generally focuses on the threat of abrupt supply disruptions. This paper suggests a more profound aspect: mitigating fossil price volatility. An extensive body of research indicates that fossil volatility significantly disrupts the economies of consuming nations, potentially exacting hundreds of billions of dollars from the US and EU economies alone. Energy security is reduced when countries hold inefficient portfolios that are needlessly exposed to fossil price risks. This paper describes essential portfolio-theory ideas and uses three case studies to illustrate how electricity-generating mixes can benefit from additional shares of wind, geothermal and other renewables. Compared to existing, fossil-dominated mixes, efficient portfolios reduce generating cost while including greater renewables shares in the mix thereby enhancing energy security. Though counter-intuitive, the idea that adding more costly renewables can actually reduce portfolio-generating cost is consistent with basic finance theory. An important implication is that in dynamic and uncertain environments, the relative value of generating technologies must be determined not by evaluating alternative resources, but by evaluating alternative resource portfolios.  相似文献   
198.
针对原油贮罐工程施工中的用电问题,提出改进安全用电的应对措施.  相似文献   
199.
对油品储运过程中存在静电危险性的原因进行了分析,提出了相应的防范措施.  相似文献   
200.
“以电代煤”环境效益分析   总被引:1,自引:0,他引:1  
目前 ,我国只有约 1 /3的煤用于发电 ,远低于发达国家的水平。要改善我国特别是城市大气环境状况 ,实行“以电代煤”是一条最有效的途径。本文以上海、北京、柳州等城市为例 ,分析了“以电代煤”的环境效益 ,并指出 ,使用电力作为最终消费方式 ,最清洁、方便 ,效率最高 ,也最易于控制。  相似文献   
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