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831.
"猪、沼、果(蔬菜)"能源生态工程实例 总被引:1,自引:0,他引:1
新安江万秋生态养殖场实施"猪、沼、果(蔬菜)"能源生态模式工程,其采用三级厌氧消化工艺,以沼气为纽带,连接种养业,不仅有效处理养殖污染物,保护农村生态环境,而且通过农业废弃物的资源化利用,增收节支,提高生态农业生产能力,实现农业增效,农民增收的目的.该工程不仅做到经济和环境保护双赢,而且为建设社会主义新农村起到了很好的示范作用. 相似文献
832.
能源结构调整与生态建设并举根治呼和浩特市大气污染 总被引:2,自引:0,他引:2
针对呼和浩特市大气污染问题,本文分析了现存问题提出了具体的解决思路。 相似文献
833.
Revisit ocean thermal energy conversion system 总被引:1,自引:0,他引:1
Huang J.C. Krock H.J. Oney S.K. 《Mitigation and Adaptation Strategies for Global Change》2003,8(2):157-175
The earth, covered more than70.8% by the ocean, receives most of itsenergy from the sun. Solar energy istransmitted through the atmosphere andefficiently collected and stored in thesurface layer of the ocean, largely in thetropical zone. Some of the energy isre-emitted to the atmosphere to drive thehydrologic cycle and wind. The wind fieldreturns some of the energy to the ocean inthe form of waves and currents. Themajority of the absorbed solar energy isstored in vertical thermal gradients nearthe surface layer of the ocean, most ofwhich is in the tropical region. Thisthermal energy replenished each day by thesun in the tropical ocean represents atremendous pollution-free energy resourcefor human civilization. Ocean ThermalEnergy Conversion (OTEC) technology refersto a mechanical system that utilizes thenatural temperature gradient that exists inthe tropical ocean between the warm surfacewater and the deep cold water, to generateelectricity and produce other economicallyvaluable by-products. The science andengineering behind OTEC have been studiedin the US since the mid-seventies,supported early by the U.S. Government andlater by State and private industries.There are two general types of OTECdesigns: closed-cycle plants utilize theevaporation of a working fluid, such asammonia or propylene, to drive theturbine-generator, and open-cycle plantsuse steam from evaporated sea water to runthe turbine. Another commonly known design,hybrid plants, is a combination of the two.OTEC requires relatively low operation andmaintenance costs and no fossil fuelconsumption.OTEC system possesses a formidablepotential capacity for renewable energy andoffers a significant elimination ofgreenhouse gases in producing power. Inaddition to electricity and drinking water,an OTEC system can produce many valuableby-products and side-utilizations, such as:hydrogen, air-conditioning, ice,aquaculture, and agriculture, etc. Thepotential of these by-products, especiallydrinking water, aquaculture andmariculture, can easily translate intobillions of dollars in businessopportunities. The current status of theOTEC system definitely deserves to becarefully revisited. This paper willexamine recent major advancements intechnology, evaluate costs andeffectiveness, and assess the overallmarket environment of the OTEC system anddescribe its great renewable energypotential and overall benefits to thenations of the world. 相似文献
834.
Bioenergy to mitigate for climate change and meet the needs of society,the economy and the environment 总被引:1,自引:1,他引:1
Changes towards environmental improvementsare becoming more politically acceptableglobally, especially in developedcountries. Society is slowly moving towardsseeking more sustainable productionmethods, waste minimisation, reduced airpollution from vehicles, distributed energygeneration, conservation of native forests,and reduction of greenhouse gas (GHG)emissions. Modern biomass, when used tosupply useful bioenergy services, has arole to play in each one of theseenvironmental drivers at both the large andsmall scales.This paper describes recent developments inbiomass supply and the technologies for itsconversion to bioenergy including biofuelsfor transport. It examines the economic,environmental and social benefits andidentifies barriers to bioenergy projectimplementation. Future opportunities forbiomass as a carbon (C) sink, a C offsetand a potential source of renewablehydrogen are discussed.Whether or not a bioenergy project iseconomically viable, as well as being trulyrenewable, sustainable and environmentallysound, is determined mainly by the sourceof biomass. The social benefits from usingbiomass are also valuable, though they areoften not clearly presented when proposingnew bioenergy projects or conductinganalyses of existing plants. Employmentrates per MWh or per GJ exceed those whenusing fossil fuel supplies to provide thesame energy service. `Ownership' bystakeholders and local communities at anearly stage in the development process isthe key to successful project developmentin order to share the benefits. Bioenergyhas a significant global role to play inthe mitigation of atmospheric GHG concentrations. 相似文献
835.
企业改革运行机制后,一个生产场所会出现多个企业并存,由此引发复合噪声源厂界的界定及超标排污费的计征等问题。应从广义上界定噪声源厂界并分清各排污单位的噪声污染责任,根据不同情况采取不同的超标排污费收费标准计征。 相似文献
836.
837.
在B3LYP/6-31G水平上全优化计算了多氯代二苯并—对-二英和多氯代二苯并呋喃(PCDD/Fs)系列物的分子结构;基于得到的分子结构描述符,依据修正的线性溶解能理论,分别建立了PCDDs和PCDFs的正辛醇/水分配系数的定量结构-性质关系模型(R2分别为0.985和0.966),并用交叉验证法对模型进行了验证(q2分别为0.983和0.936),用t-检验对各变量进行了检验.检验结果表明,模型的预测能力优于AM1法、单苯环氯取代指数法和拓扑量子方法得出的模型. 相似文献
838.
绿色机动车—燃料电池汽车 总被引:2,自引:0,他引:2
简要叙述了燃料电池汽车的技术特点,主要有:能量转化效率高,CO2排放量比内燃机汽车低,基本不产生有毒气体,不要充电。在此基础上较详细地介绍了世界各国的燃料电池汽车研究现状,并针对上海市机动车污染严重的现状,提出了发展燃料电池汽车及其相关产业的建议。 相似文献
839.
840.
Tuhkanen Sami Lehtilä Antti Savolainen Ilkka 《Mitigation and Adaptation Strategies for Global Change》1999,4(2):91-112
The reduction of carbon dioxide (CO2) emissions may be quite expensive and it is necessary to consider reduction measures for other anthropogenic greenhouse gases, such as methane (CH4) and nitrous oxide (N2O) as well. Their contribution to the total GHG emission from Finland is about 15–20%. In Finland most of the CH4 emissions are due to waste management, agriculture and burning processes. N2O emissions originate from burning processes, agriculture, industry and atmospheric deposition of nitrogen. The cost-effective reduction of the Finnish GHG emissions has been studied with the EFOM-ENV model, which is a quasi-dynamic linear energy system optimisation model. The target function to be minimised is the total discounted cost for the modelled system. In this study the model has been expanded to cover all well-known anthropogenic CO2, CH4 and N2O sources and reduction measures. The results indicate it is economic to reduce the emissions of CO2, CH4 and N2O in Finland. It is profitable to exploit the economic reduction potential of CH4 and N2O, because then the abatement of CO2 emissions does not need to be as extensive as when the reduction is aimed only at CO2 emissions. The inclusion of CH4 and N2O decreases the annual reduction costs about 20% in the year 2010. 相似文献