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411.
Determination of the amount of greenhouse gas (GHG) emitted during municipal solid waste incineration (MSWI) is complex because both contributions and savings of GHGs exist in the process. To identify the critical factors influencing GHG emissions from MSWI in China, a GHG accounting model was established and applied to six Chinese cities located in different regions. The results showed that MSWI in most of the cities was the source of GHGs, with emissions of 25–207 kg CO2-eq t?1 rw. Within all process stages, the emission of fossil CO2 from the combustion of MSW was the main contributor (111–254 kg CO2-eq t?1 rw), while the substitution of electricity reduced the GHG emissions by 150–247 kg CO2-eq t?1 rw. By affecting the fossil carbon content and the lower heating value of the waste, the contents of plastic and food waste in the MSW were the critical factors influencing GHG emissions of MSWI. Decreasing food waste content in MSW by half will significantly reduce the GHG emissions from MSWI, and such a reduction will convert MSWI in Urumqi and Tianjin from GHG sources to GHG sinks. Comparison of the GHG emissions in the six Chinese cities with those in European countries revealed that higher energy recovery efficiency in Europe induced much greater reductions in GHG emissions. Recovering the excess heat after generation of electricity would be a good measure to convert MSWI in all the six cities evaluated herein into sinks of GHGs.  相似文献   
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413.
将河南平顶山煤气公司原煤气输配系统改造成为自动恒压控制系统,从而提高安全系数,降低煤气输配电耗。  相似文献   
414.
水库溃坝损失及其计算方法研究   总被引:7,自引:1,他引:6  
施国庆  李志强 《灾害学》1998,13(4):28-33
主要研究水库渍坝损失及其计算方法.分析了水库溃坝及其损失的特点,提出了溃坝洪水淹没损失的直接经济损失的实物型损失与收益型损失、间接经济损失、非经济损失的内容及其计算方法,并探讨了库区坍岸损失与清决工程损失计算方法.  相似文献   
415.
Co-disposal of refuse with municipal solid waste incinerator (MSWI) bottom ash (IBA) either multi-layered as landfill cover or mixed with refuse could pose additional risk to the environment because of enhanced leaching of heavy metals, especially Cu. This study applied short-term accelerated weathering to IBA, and monitored the mineralogical and chemical properties of IBA during the weathering process. Cu extractability of the weathered IBA was then evaluated using standard leaching protocols (i.e. SPLP and TCLP) and co-disposal leaching procedure. The results showed that weathering had little or no beneficial effect on Cu leaching in SPLP and TCLP, which can be explained by the adsorption and complexation of Cu with DOM. However, the Cu leaching of weathered IBA was reduced significantly when situated in fresh simulated landfill leachate. This was attributed to weakening Cu complexation with fulvic acid or hydrophilic fractions and/or intensifying Cu absorption to neoformed hydr(oxide) minerals in weathered IBA. The amount of total leaching Cu and Cu in free or labile complex fraction (the fraction with the highest mobility and bio-toxicity) of the 408-h weathered IBA were remarkably decreased by 86.3% and 97.6% in the 15-day co-disposal leaching test. Accelerated weathering of IBA may be an effective pretreatment method to decrease Cu leaching prior to its co-disposal with refuse.  相似文献   
416.
于亢亢  苏晶  赵华  高健 《中国环境科学》2021,40(12):5520-5530
虽然以往对于环境库兹涅兹曲线(EKC)的研究中考虑了正式制度因素如政府机构监督,但是较少考虑非正式制度因素.本文重点检验两种制度情境的影响,微观层面的环境态度形成的非正式制度以及宏观层面的环保机构监督形成的正式制度对大气污染排放量的影响.基于CGSS2010-2013和2015年的数据库,从中提取出体现环境态度的问题,将其赋值指标化后,作为制度情境纳入环境方程.经过公开数据的收集,得到我国26个省份2010-2014年5年的面板数据.通过固定效应和随机效应模型,发现机构监督与人均GDP的交互项对氮氧化物、烟(粉)尘、二氧化硫排放都有影响,但是公众态度与人均GDP的交互项只对烟(粉)尘排放有影响,从而对不同制度情境下的环境库兹涅兹曲线进行了探索.  相似文献   
417.
罗尔斯顿的环境伦理学,受机体哲学的影响,他的创造性理论,是对怀特海创造性概念的运用和发展。他扬弃了怀特海的神学形而上学的原则,吸收了机体哲学的有机联系的原则,并把创造性引入了自然的发生系统。  相似文献   
418.
A new imidacloprid (IMI) degrading bacterium Z-9 (deposited number CGMCC 6648) was isolated and identified as Pseudoxanthomonas indica by 16S rRNA gene analysis. Two metabolites were identified as olefin and 5-hydroxy IMI by liquid chromatography-mass spectrometry and nuclear magnetic resonance analysis. P. indica CGMCC 6648 degraded 70.1% of IMI (1.22 mmol L?1) and formed 0.93 mmol L?1 5-hydroxy IMI and 0.05 mmol L?1 olefin IMI in 6 days and in the presence of 100 mmol L?1 glucose. The half-life of IMI degradation was 3.6 days. P. indica CGMCC 6648 transforms IMI via a co-metabolism mechanism and different carbohydrates have significant effects on 5-hydroxy IMI formation, whereas different organic acids have substantial effects on olefin IMI production. Lactose is the best co-substrate for IMI degradation and 5-hydroxy IMI formation with 0.77 mmol L?1 degraded and 0.67 mmol L?1 formed in 48 h, respectively. Pyruvate is the best co-substrate for olefin IMI formation with 0.17 mmol L?1 produced in 96 h for all carbon sources tested. Pyruvate significantly stimulates the conversion of 5-hydroxy IMI to olefin IMI, whereas glucose slightly inhibits this reaction. P. indica CGMCC 6648 rapidly degrades IMI and forms olefin IMI, which may enhance its potential for biodegradation of IMI and increase its insecticidal activity, which can decrease the IMI dosage required.  相似文献   
419.
420.
The estrogenic activities of source water from Yangtze River, Huaihe River, Taihu Lake and groundwater in Yangtze River Delta in the dry and wet season were determined by use of reporter gene assays based on African green monkey kidney (CV-1) cell lines. Higher estrogenic activities were observed in the dry season, and the estrogenic potentials in water samples from Taihu Lake were greater than other river basins. None of the samples from groundwater showed estrogen receptor (ER) agonist activity. The 17β-Estradiol (E2) equivalents (EEQs) of water samples in the dry season ranged from 9.41 × 10?1 to 1.20 × 101 ng E2 L?1. In the wet season, EEQs of all the water samples were below the detection limit as 9.00 × 10?1 ng E2 L?1 except for one sample from Huaihe River. The highest contribution of E2 was detected in Yangtze River as 99% of estrogenic activity. Nonylphenol (NP, 100% detection rate) and octylphenol (OP, 100% detection rate) might also be responsible for the estrogenic activities in water sources. Potential health risk induced by the estrogenic chemicals in source water may be posed to the residents through water drinking.  相似文献   
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