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911.
将从分析美国新能源战略的有效性和成本入手,梳理和评估美国政府的新能源方案,同时提出一些关于清洁能源的建议。选择了美国推广清洁能源行为作为对象来讨论,不仅因为美国是世界上最大的清洁能源和可再生能源的投资者,同时还强调美国在运行这一投资的时候并没有使用自由市场来推动,而是完全由政府买单和控制。具体要讨论的方案是:核清理;低收入家庭房屋保暖;先进的汽车电池(牵引)系统及组件;电动汽车补贴退税制度。通过对每个方案内容的阐述和成本、效益的分析,来评估这些方案是否是有价值的和值得继续的。最后的结论可以归纳为这些清洁能源实施项目非常低效,并且提出一系列的证据表明这些项目在没有政府巨额经费支持的情况下是无法继续的,同时表明在没有严格的项目完成日期、持续发生超过预算的额外支出的情况下,政府的支持计划很可能和初衷背道而驰  相似文献   
912.
Oil and natural gas exploration and production (E&P) activities generate emissions from diesel engines, compressor stations, condensate tanks, leaks and venting of natural gas, construction of well pads, and well access roads that can negatively impact air quality on both local and regional scales. A mobile, autonomous air quality monitoring laboratory was constructed to collect measurements of ambient concentrations of pollutants associated with oil and natural gas E&P activities. This air-monitoring laboratory was deployed to the Allegheny National Forest (ANF) in northwestern Pennsylvania for a campaign that resulted in the collection of approximately 7 months of data split between three monitoring locations between July 2010 and June 2011. The three monitoring locations were the Kane Experimental Forest (KEF) area in Elk County, which is downwind of the Sackett oilfield; the Bradford Ranger Station (BRS) in McKean County, which is downwind of a large area of historic oil and gas productivity; and the U.S. Forest Service Hearts Content campground (HC) in Warren County, which is in an area relatively unimpacted by oil and gas development and which therefore yielded background pollutant concentrations in the ANF. Concentrations of criteria pollutants ozone and NO2 did not vary significantly from site to site; averages were below National Ambient Air Quality Standards. Concentrations of volatile organic compounds (VOCs) associated with oil and natural gas (ethane, propane, butane, pentane) were highly correlated. Applying the conditional probability function (CPF) to the ethane data yielded most probable directions of the sources that were coincident with known location of existing wells and activity. Differences between the two impacted and one background site were difficult to discern, suggesting the that the monitoring laboratory was a great enough distance downwind of active areas to allow for sufficient dispersion with background air such that the localized plumes were not detected.
ImplicationsMonitoring of pollutants associated with oil and natural gas exploration and production activity at three sites within the Allegheny National Forest (ANF) showed only slight site-to-site differences even with one site far removed from these activities. However, the impact was evident not in detection of localized plumes but in regional elevated ethane concentrations, as ethane can be considered a tracer species for oil and natural gas activity. The data presented serve as baseline conditions for evaluation of impacts from future development of Marcellus or Utica shale gas reserves.  相似文献   
913.
This paper examines various health effects of photochemical air pollution in Japan, primarily through the review of epidemiological studies. Health effects discussed include subjective respiratory symptoms, respiratory function testing, ocular effects, and hospital diagnostic tests. The downward trend in oxidant cautions and paralleled health effects, as reported by the Japanese Environmental Agency, are discussed. The methods determined by Japanese ordinance for measurement of oxidants, SO2, NO x , and CO are described.  相似文献   
914.
915.
Polyurethane foam was incorporated as a prefilter on standard hi-volume samplers of the National Air Sampling Network (NASN) in an exploratory study. The foam selectively filtered particles of various sizes. The characteristics of the particles passing through the foam approached the respirable size fraction as defined by reports of the Atomic Energy Commission. The respirable fraction was then collected on a glass-fiber filter. Parameters such as pore size and thickness of the foam, air flow rates, and loadings were studied to determine their effects on the filtration of “respirable” dust. Ambient air was the particulate source, and sizing was accomplished by an Andersen sampler coupled with nephelometric analyses. Some sizing was also done microscopically. The foam was evaluated at several locations to account for possible variations in ambient air over areas of different industrial complexity.  相似文献   
916.
917.
The subject of energy choices and public policy is one that has interested me at a professional level. The outlook for energy supply for Americans is uncertain. Will the OPEC crank the per barrel price of world oil up again this fall by three or four dollars? We don’t know. Will the cost of finding and developing new domestic oil reserves continue to rise, and will the domestic production continue to fall as it has been doing since 1970? We don’t know. Would regulating the price of old oil and natural gas entering into interstate commerce bring forth significantly increased supplies? We don’t know. The chances for reducing oil consumption—or at least checking the rate of increase—are equally uncertain. Will still higher prices, brought on by whatever means, cause people and industries to use less oil? We don’t know. Will demand shift away from oil and natural gas to cheaper, more plentiful energy sources? We don’t know. Will penalties, taxes, or exhortations get the motor vehicle industry to produce more gasoline efficient cars and trucks? We don’t know. We may not even get a chance to try. Will new, less energy intensive lifestyles take over? We don’t know.  相似文献   
918.
Large quantities of nahcolite ore, a naturally occurring mineral containing between 70 and 90% sodium bicarbonate are known to occur in the Green River Formation of the Piceance Creek Basin of northwestern Colorado.1 Deposits occur in two major forms, as either bedded or disseminated ore. In the latter case, the host rock is oil shale, a dolomitic marlstone containing kerogen material. Bench and pilot scale studies have shown finely divided nahcolite ore to be an effective SO2 sorbent in baghouse filters.2 These studies form the basis of the nahcolite ore injection process as a means for controlling SO2 emissions to the environment.3 Although there have been published investigations of reactions of SO2 with Na2CO3and NaHCO3, 4 no reference could be found to a systematic study of nahcolite ore reacting with SO2.  相似文献   
919.
Solid growth is seen for the air pollution control industry for the rest of the century. Over the next twelve years purchases of particulate control equipment in the U.S. will grow at a rate considerably better than the GNP; growth rates in developing countries will be even higher. The portion of air pollution control expenditures represented by FGD systems is predicted to rise from its current level of 12 percent to 62 percent in 1991 if acid rain legislation is passed as predicted. A significant market is seen also for municipal, industrial and agricultural waste incinerators. Geography plays an important role in the strength of the industry; in the future, industrialized countries will be the sites of new designs and applications, while developing countries will be the life extension of the tried and proven designs. Industrywide, new product development is seen as an underused route to success.  相似文献   
920.
Techniques were developed to sample and analyze the Cr content of participate samples with emphasis on determining the concentration of the carcinogen Cr+6. Cr+6 is extracted to alkaline solution and analyzed colorimetrically. Residual particles are extracted with acid solution to remove soluble Cr+3, which is determined by atomic absorption spectrometry. This methodology was tested on samples from three diverse types of sources: a ferrochrome smelter, a chemical plant, and a refractory brick plant. Identical quadruplicate samples were collected to determine accuracy and precision of the collection and analysis procedures, and extraction of Cr+6 and Cr+3. A statistical analysis revealed that the precision of Cr+6 analysis is comparable to that of the particulate mass determination. The stability of Cr+6 In particulate form and in solution was determined. Size resolved particulate samples were collected to determine the particle size versus the Cr+6 content. At the ferrochrome smelter and the chemical plant the majority of the Cr+6 was contained in the respirable particles. The accuracy and completeness of the chemical methods employed were verified by neutron activation analysis, x-ray photoelectron spectroscopy, and scanning electron microscopyenergy dispersive x-ray analysis.  相似文献   
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