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81.
能源承载力预测分析方法的研究与应用研究   总被引:1,自引:0,他引:1  
能源需求和人口、经济密切相关。能源需求分析是在一定的人口和经济增长假设下进行的。从投入产出角度看,能源需求的高低取决于终端需求与满足终端需求的中间过程。经济结构的变化,经济增长模式的选择,技术进步,优质能源的可获得性,环境保护要求等因素会对终端需求和中间过程产生影响。由于资源对国家和地区的重要性,资源承载力的研究显得尤为重要。因此有必要对一个区域的能源需求量作出预测和分析,提高区域发展和管理的科学性,从而实现区域的可持续发展。  相似文献   
82.
以2010年的LandsatTM遥感影像图和武夷新区总体规划中新区2030年土地利用规划图为基础数据,在RS和GIS技术支持下,结合马尔科夫模型和景观生态学方法分析了未来武夷新区的土地利用与案观格局变化。结果表明:在规划实施后,建设用地通过占用耕地和林地而大面积增加,使得林地和耕地相应减少,人类活动对景观的干扰强度增大,区域景观斑块形状趋于规则简单化,斑块总数有所减少,平均斑块面积增大,景观连接度增强,破碎化程度降低,景观多样性增加。  相似文献   
83.
文章以榆林能源化工基地代表性的支柱产业为例,开展依靠科技进步提升清洁生产水平的节能减排潜力分析。分析结果表明,至"十二五"末期榆林能源化工基地的支柱产业分别将清洁生产水平提高至一级或二级,可减少的二氧化硫排放量是3 451.8吨/年和1 094.3吨/年,氮氧化物排放量是5 333.5吨/年和1 962.5吨/年。  相似文献   
84.
研究采用铁为阳极电化学法处理直接黄11染料模拟废水脱色性能的影响进行研究。影响因素包括:电流密度、pH值、染料浓度和电解质浓度。研究结果表明,电流密度大有利于染料废水脱色,但能耗消耗大;初始溶液在中性条件下不仅取得很好的处理效果,而且脱色能耗较低;随着染料初始浓度增加脱色率和脱色能耗降低的趋势;随着电解质浓度升高染料脱色率下降的趋势,脱色能耗先减少,然后缓慢增大。在染料初始浓度50 mg/L、pH值为7.11、电流密度2.083 mA/cm2、电解质Na2SO4浓度0.01 mol/L、温度20℃、搅拌速度600 r/min、电解时间60min条件下,脱色率达到92.2%,脱色能耗1.709 kW.h/kg染料。  相似文献   
85.
结合企业清洁生产理论,根据污水处理厂实际情况,从“节能、降耗、减排、增效”出发,详细阐述了污水厂实行清洁生产的途径。指出节约电能、新鲜水、药剂,减少污染物排放是污水处理厂清洁生产的主要出发点。并进行实例分析。  相似文献   
86.
《环境影响评价法》第31条一直是该法备受关注和饱受争议的对象,如何全面正确地认识这一条款的规定才能更好地实施和完善环境影响评价制度?通过对31条两种情形下建设单位行为的主观恶性的再分析、对照环境影响评价的价值和目的对该责任条款的再认识、对环境影响评价执法难的根源追寻等方面来探讨对31条的全新认识和补充完善。  相似文献   
87.
沼液复合型杀虫剂的田间应用试验研究   总被引:3,自引:1,他引:2  
通过沼液复合型杀虫剂的田间应用试验,对各种沼液复合型杀虫剂的抗病防虫性能进行了深入研究.在大田应用条件下测试了沼液复合型杀虫剂的杀虫效果.结果表明,该沼液复合型杀虫剂对蚜虫的毒杀作用均比较明显.为了推进沼液复合型杀虫剂的商业化进程,提出便于其田间应用的各种最佳配比浓度,即BP01号、BP02号、BP03号、BP04号、BP05号沼液复合型杀虫剂抗病防虫性能最佳的配比分别为9 500倍液、26000倍液、11 667倍液、22 000倍液和13 333倍液.  相似文献   
88.
PROBLEM: A stated objective of driver education in North America is to produce safer drivers, typically defined as drivers less likely to crash. This paper examines the extent to which driver education has achieved this objective independently as well as the extent to which such programs can support the success of graduated licensing in reducing young driver crashes. In so doing, it discusses past experiences, recent developments, and the future direction of driver education and training in relation to graduated driver licensing. METHOD: Literature review and synthesis. RESULTS: Driver education programs have yet to demonstrate consistent attainment of their safety objectives. Moreover, they have not been found to enhance the safety effectiveness of graduated licensing programs--indeed, some practices, for example, "time discounts" for driver education have actually had a detrimental effect on teen safety. DISCUSSION: Despite its disappointing safety record to date, it is important not to abandon driver education. In particular, there are opportunities to improve driver education so that it achieves its safety objectives, and ensure that programs in the future complement graduated driver licensing and contribute to its overall safety benefits. Current and future efforts to improve driver education and better integrate it with graduated licensing programs, however, need to be rigorously evaluated to determine what does and does not work to reduce young driver crashes, and as importantly, to understand why this is the case. IMPACT ON INDUSTRY: Improved driver education integrated with graduated driver licensing has potential safety benefits.  相似文献   
89.
The catalyst of Fe-Mo/ZSM-5 has been found to be more active than Fe-ZSM-5 and Mo/ZSM-5 separately for selective catalytic reduction (SCR) of nitric oxide (NO) with NH3. The kinetics of the SCR reaction in the presence of O2 was studied in this work. The results show that the observed reaction orders were 0.74-0.99, 0.01-0.13, and 0 for NO, O2 and NH3, respectively, at 350-450℃. And the apparent activation energy of the SCR was 65 kJ/mol on the Fe-Mo/ZSM-5 catalyst. The SCR mechanism was also deduced. Adsorbed NO species can react directly with adsorbed ammonia species on the active sites to form N2 and H2O. Gaseous O2 might serve as a reoxidizing agent for the active sites that have undergone reduction in the SCR process. It is also important to note that a certain amount of NO was decomposed directly over the Fe-Mo/ZSM-5 catalyst in the absence of NH3.  相似文献   
90.
Some emerging technologies are expected to be pivotal for solving many of the environmental challenges faced today, especially those related to energy. However, many of these technologies may incur significant environmental impacts over their life cycle, while having environmental benefits during their use. This paper presents results of a Life Cycle Assessment (LCA) of a proposed type of nanophotovoltaic, quantum dot photovoltaic (QDPV) module. The LCA is confined to the stages of raw materials acquisition, manufacturing, and use. The impacts of QDPV are compared with other types of PV modules and energy sources - both renewable and nonrenewable. To provide a comprehensive comparative assessment, QDPV modules were compared with mature as well as emerging PV types for which data are available. Comparative assessment with other types of energy sources includes coal, oil, lignite, natural gas, diesel, nuclear, wind, and hydropower.QDPV modules may have the potential to overcome two current barriers of solar technology: low efficiencies and high manufacturing costs. If higher efficiencies are realized, QDPV modules could pave the way to large scale implementation of solar energy, helping nations move toward greater energy independence. On the other hand, candidate materials as quantum dots for solar cell applications are mostly compound semiconductors such as cadmium selenide, cadmium telluride, and lead sulfide which may be toxic and for which renewable options are limited. Toxic effects of these materials may be exacerbated by their nanoscale features.The LCA was carried out using the software SimaPro, and the Ecoinvent Life Cycle Inventory (LCI) database supplemented with available literature and patent information. Our results indicate that while QDPV modules have shorter Energy PayBack Time (EPBT), lower Global Warming Potential (GWP), SOx and NOx emissions than other types of PV modules, they have higher heavy metal emissions, underscoring the need for investigation of emerging technologies, especially nano-based ones, from a life cycle perspective. QDPV modules are better in all impact categories assessed than carbon-based energy sources but they have longer EPBT than wind and hydropower and higher GWP.  相似文献   
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