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281.
A community-based Clean Development Mechanism (CDM) project – asolar water heating project in a low-income community in South Africa –is analysed to illustrate the methodological and policy challenges that faceimplementation of the Kyoto Protocol to the United Nations FrameworkConvention on Climate Change. We evaluate four baseline options, andthree potential CDM interventions. The emissions reductions range from –670 to +5 929 Mg CO2 per year, with all option but oneshowing positive emission reductions. Using metered solar water heatingwith liquefied petroleum gas back-up as the CDM intervention, and electricstorage geysers as the baseline, the annual emissions reductions are 5686 Mg CO2. The cost-effectiveness from the national perspective,which is the incremental life cycle costs divided by the lifetime emissionsreductions, is –$18 per Mg CO2 From the perspective of theCDM investor, however, the cost-effectiveness is $5.2 per mgCO2, assuming that the investor receives all of the carbon credits forproviding the incremental capital investment. From our analysis, weconclude that using the current technology (kerosene stoves) as a baselineis probably not appropriate because it does not reflect likely future trendsand also penalises the community for their poverty and current lack ofinfrastructure. We also highlight the importance of credit sharing, and howit affects the cost-effectiveness of the project from the CDM investor'sperspective. The lessons from this analysis are important for the currentinternational policy debate on how to preferentially treat small-scale CDMprojects.  相似文献   
282.
防止煤矿井筒出现结冰现象,对保证矿井安全生产和正常生产至关重要。无风机方式有别于其他传统的方式,是一种技术可靠、造价低、非常适合于我国广大地区的井筒防冻方式。  相似文献   
283.
通过对中国北方城市SO2污染的季节性特点进行分析发现,减少采暖燃煤SO2排放,解决采暖期SO2污染,是SO2年日均值达标的关键。而改变采暖期能源结构和采暖方式,将传统燃煤取暖改为清洁能源取暖,提高电厂排放SO2占SO2排放总量中的比例,可以解决大多数北方城市采暖期SO2难以达标的问题。同时,通过电厂脱硫设施建设可有效控制SO2排放总量。  相似文献   
284.
选取印刷线路板(简称PWBs)和覆铜板(简称CCL)两种典型电子废弃物代表,应用氧弹量热仪和热重分析仪分别对其进行高位定容弹筒发热量测试和热重分析。结果表明:对于PWBs,温度控制在250~520℃时,样品剩余质量随着升温速率的增加而增多,当温度超过520℃后趋势相反;CCL的分界温度在410℃附近。随着升温速率的提高,PWBs和CCL样品的最大失重速率会推迟出现10~20℃,且两种样品的DTG曲线均随着升温速率的提高整体向高温区偏移。反应初始温度、最终温度以及反应最大速率所对应的峰值温度均随着升温速率的增大而升高。当升温速率β增大时,PWBs和CCL样品的DTG峰值温度Tp值均升高;CCL样品的最大热解速率νmax变化趋势与Tp相同,但PWBs样品的νmax随升温速率变化不大。  相似文献   
285.
本文根据阳高县城2012年、2013年采暖季SO2、NO2监测浓度,结合2013年集中供热所替代土小采暖炉灶减排的污染物排放量,采用AERMOD模式进行预测验证,并对模式参数取值进行了探讨,以期对模型的同类型应用提供参考。  相似文献   
286.
The gasification reaction of Nantong inferior coal was investigated in a laboratory fixed-bed reactor under CO2 and O2/H2O atmospheres. The effects of the bed temperature and inlet-gas concentration on the yields of CO, H2, and CH4 were studied. The effects of coal ash and particle size on the fixed-carbon conversion were also investigated, and kinetic analysis was conducted with a homogeneous model. The product-gas-heating value and fixed-carbon conversion increased when the temperature was increased from 950 °C to 1100 °C under CO2 atmosphere. When the inlet-CO2 concentration was increased from 50 to 100 vol.%, the low heating value of the product gas and carbon conversion ratio slightly increased. During the gasification of inferior coal under the O2/H2O atmosphere, the CO concentration increased rapidly with increasing temperature. The H2 and CH4 concentrations increased initially and then decreased. The maximum gas heating value of 7934 kJ/m3 was obtained under the O2 concentration of 70 vol.% at a bed temperature of 1050 °C. The cold-gas efficiency increased with increasing temperature and became 40.6% and 86.4% at 1100 °C under the CO2 and O2/H2O atmospheres, respectively. The gasification reaction of the Nantong inferior coal strongly depended on the content of inherent inorganic matter. The gasification rates for both the CO2 and O2/H2O atmospheres were independent of the particle size. The activation energy for the CO2 and O2/H2O gasification reactions were 137 and 81 kJ/mol, respectively. The gasification reactions of the Nantong coal, which was performed under two different atmospheres, were compared and the reaction activity of the gasification reaction under CO2 atmosphere was found to be much lower than that under the O2/H2O atmosphere.  相似文献   
287.
人工湿地作为一种造价较省,运行成本低的污水处理技术,目前已经得到了广泛的应用.但是在北方地区,人工湿地受到冬季气候影响,无法正常运行,降低了它的使用效率.试验针对北方冬季低温环境下,人工湿地无法正常运行的问题,对3种不同的保温措施进行历时两年的对比试验,通过对TP、TN、NH4+-N和COD等4种主要污染物和人工湿地出水水温的跟踪监测,检验了不同保温措施的效果.试验结果表明:在冬季,使用薄膜法保温措施的处理系统中,COD、TN和NH4+-N的去除率分别为30%~45%、40%~60%和35%~60%,比温棚法和冰封法的出水中污染物去除率高10%~20%.TP在出水中含量波动较大,去除率为19%~70%,伴有磷释放现象,但是在薄膜保温下TP的去除效果也要好于温棚和冰封.经过SPSS16.0分析,薄膜保温的人工湿地出水水质与冰封和温棚法相比具有显著性差异.在对人工湿地曝气槽和出水口的污水水温进行监测发现,利用薄膜保温的人工湿地出水口水温高于冰封和温棚的水温,进一步证明薄膜保温可以有效提高人工湿地内的温度,为人工湿地正常运行提供了保证.而且薄膜保温措施的操作简便、造价低,适合推广应用.  相似文献   
288.
Abstract

A magnetic molecularly imprinted polymer (MMIP) for chloramphenicol was prepared using a surface-imprinted and microwave-heating-induced polymerization method. The surfaces of the magnetic particles were first double-bond functionalized with 3-(trimethoxysilyl)propyl methacrylate (γ-MPS), followed by the copolymerization of 4-vinyl pyridine (4-VP) and trimethylolpropane trimethacrylate (TRIM) in the presence of chloramphenicol as a template and 1,1-azobis(cyclohexane-carbonitrile) (ABCN) as an initiator in a mixture of dimethyl sulfoxide and water with microwave heating at 80°C. The magnetic polymer possesses supraparamagnetic properties and was used to concentrate and cleanup chicken feed extract, followed by chromatographic separation using a Lichrospher®100 RP C8 column and detection with two multi-reaction monitoring transitions at m/z 321→ 152 and m/z 321→ 257. The mean recoveries obtained at two spiking levels were in the range of 94.6–100% The relative intra- and inter-day standard deviations were in the range of 1.4–2.6% and 5.1–5.7%, respectively. The detection limit of the method was 0.12 µg kg?1. This confirmatory method was successfully applied to determine chloramphenicol in chicken feed samples.  相似文献   
289.
为研究西安市南郊地区采暖期大气颗粒物PM2.5的污染浓度及水溶性成分,使用颗粒物采样器于2009年1月6日-2009年2月15日进行PM2.5采样。将24 h分为8个阶段,每天3 h定时采样。结果表明,西安市南郊地区采暖期PM2.5明显污染,24 h中PM2.5污染状况最严重的时段为21:00-23:59;PM2.5中NH4^+、NO3^-和SO42^-是其最主要的水溶性组分,在PM2.5中的平均质量混合比分别为10.225%、13.698%和15.650%,三者在PM2.5中质量混合比最高的时段分别为06:00-08:59、03:00-05:59和18:00-20:59。  相似文献   
290.
根据《煤电节能减排升级与改造行动计划》以及《国家环境保护"十三五"规划纲要》,我国燃煤电厂污染物排放浓度应达到现行燃气锅炉标准,现行颗粒物监测仪器需要进行更新。现在市面上有2种污染源颗粒物采样管可对改造后电厂进行颗粒物采样监测,采用平行实验法对这2种采样管所采集的颗粒物质量结果进行分析,同时使用验证实验分析2种采样管颗粒物采集质量结果产生差异的原因,并对如何提升燃煤电厂颗粒物监测的准确性提出建议。  相似文献   
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