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191.
Parviz Abdolmaleki Faezeh Ghanati Hassan Sahebjamei Amir Sabet Sarvestani 《The Environmentalist》2007,27(4):435-440
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.
Michael Martin Linda Cox Stuart Nakamoto John Halloran 《Journal of the American Water Resources Association》1990,26(1):35-39
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.
骆祚炎 《湖南环境生物职业技术学院学报》2003,9(2):165-169
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.
S. Meunier D. T. Manning L. Quéval J. A. Cherni P. Dessante D. Zimmerle 《国际发展与全球生态学杂志》2019,26(6):547-559
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
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Portfolio-Based Electricity Generation Planning: Policy Implications For Renewables And Energy Security 总被引:4,自引:0,他引:4
Shimon Awerbuch 《Mitigation and Adaptation Strategies for Global Change》2006,11(3):693-710
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
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