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971.
结合主要污染物"十二五"总量控制规划编制工作经验,对新疆畜禽养殖业主要污染物的减排潜力及途径进行分析,宏观测算出新疆畜禽养殖业"十二五"期间的减排潜力,并提出新疆畜禽养殖业的减排途径及方法,为新疆主要污染物"十二五"减排工作提供合理化建议。  相似文献   
972.
北京市机动车尾气排放PM10组分特征研究   总被引:7,自引:4,他引:3  
为提高机动车尾气排放可吸入颗粒物PM10成分谱的代表性和准确性,提出并采用在机动车尾气检测线上采用稀释通道采样器随机采集机动车排出PM10的采样方法。采集了591辆轻、重型汽油车和柴油车尾气排放PM10,测试并分析了颗粒物的27种组分。数据表明:机动车排放颗粒物PM10中含量丰富的组分为OC、EC、NH+4、NO-3和SO2-4;柴油车排放PM10中OC和EC的质量分数为49.08%,是汽油车(38.38%)的1.3倍,汽油车的OC/EC(2.36)是柴油车(0.78)的3倍;汽油车排放PM10中的二次转化产物(SO42-+NH4++NO3-)的质量分数为19.37%,是柴油车(3.57%)的5.4倍;汽油车排放NH+4是柴油车的5.3倍。  相似文献   
973.
In this paper we introduce a new method of analysing the relationship between nitrogen dioxide (NO2) and oxides of nitrogen (NOx) concentrations using data from the UK National Air Quality Archive. The study includes analyses of measurements from two different types of site in London, a kerbside site: Cromwell Rd, and three background sites: Bridge Place, London Bloomsbury and West London, over several years (1991–7). The data in some years showed that hourly NO2 concentrations exceeded the UK Standard of 150 ppb. Data were binned, averaged, and polynomials fitted at each site. Analysis of the resulting polynomials was used to estimate reductions in NOx emission required to achieve the National Air Quality Strategy Objective. Examination of the empirical ratio NO2:NOx (the 'yield') gives an indication of the sensitivity of the NO2 to NOx controls and the amount of NO2 that would arise from modelled values of total oxides of nitrogen. The response of NO2 to emission changes is very non-linear, implying 30–45% controls on NOx may be required.  相似文献   
974.
Exhaust emission and performance characteristics were evaluated in a Toyota van, powered by a 21 indirect injection (IDI) naturally aspirated diesel engine, operating on vegetable based waste cooking oil methyl ester (WCOME).Tests were performed on a chassis dynamometer and the data were compared with previous results conducted on the same vehicle using mineral diesel fuel. The data obtained includes smoke opacity, carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2), nitrogen dioxide (NO2), nitric oxide (NO), sulfur dioxide (SO2) and brake power. Engine lubricating oil samples were also taken. Results from this study indicated a difference of approximately 9% in brake power between the two fuels. WCOME developed a significant lower smoke opacity level and reduced CO, CO2, SO2 emissions. However, O2, NO2 and NO levels were higher with the vegetable oil based fuel. Power values were comparable for both fuels. Lubricating oil analysis gave little change of viscosity and wear metal concentrations after 2887km were: Silicon 35ppm, Chromium 3.3ppm, Iron 33.8ppm, Copper 14.1ppm and lead 78.6ppm.  相似文献   
975.
气相分子吸收光谱法测定海水中的硝酸盐氮   总被引:1,自引:0,他引:1  
采用GMA3212型气相分子吸收光谱仪测定海水中的硝酸盐氮,在常规海水中硝酸盐氮质量浓度范围内(0~4.00 mg/L)线性良好(线性相关系数0.999 9),检出限为0.004 mg/L,标准溶液平行测定的相对标准偏差小于或等于1.44%,相对误差小于或等于1.33%,实际水样加标回收率为96.0%~102%。通过与国标方法镉柱还原法的比对实验,2种方法在精密度、准确度、实样比对等方面均无显著性差异,测定结果具有良好的一致性。气相分子吸收光谱法具有操作简便、分析快速准确、试剂消耗少、适合批量测定等优点,是值得推介的先进方法。  相似文献   
976.
太湖流域水污染物总量减排绩效评估体系建立   总被引:1,自引:0,他引:1  
在充分考虑太湖流域水污染物总量减排工作特点的前提下,采用主客观相结合的方法,选择了27个绩效评估指标,确定各评价因子的权重,构建了太湖流域水污染物总量减排绩效评估体系。在此基础上,对2005—2012年太湖流域水污染物总量减排绩效进行评估。结果表明,2010—2012年的太湖流域水污染物总量减排效果较2005—2009年有所提高,减排工作取得了较明显成效,但是距理想状态仍有一定差距。该评估体系的建立为推动流域水污染物减排绩效评估工作的发展提供了科学依据。  相似文献   
977.
朱毅  李晓霞  王俊  李春 《环境工程学报》2012,6(9):2995-3000
针对大豆深加工高浓度有机废水厌氧出水的特点,采用移动床生物膜反应器-沉淀池-厌氧池(MBBR-SA)工艺进行处理,重点考察了其COD去除、脱氮以及污泥减量化的性能。处理前厌氧出水水质参数为COD 1 350~1 851 mg/L、TN 45~73 mg/L和TP 35~55 mg/L。结果表明,经过70 d的运行,在最佳水力停留时间(HRT)1.68 d与最佳回流比0.75条件下,出水平均COD、TN和NH4+-N浓度分别为91.5、12.4和11.4 mg/L,分别达到了《城镇污水处理厂污染物排放标准》二级标准、二级标准和一级B标准,其平均去除率分别为96.0%、87.4%和88.3%;该工艺未排放剩余污泥,其表观污泥产率为0.13,比MBBR降低了43.5%,具有明显的污泥减量化特性。  相似文献   
978.
柴油机SCR催化器载体结构参数优化   总被引:2,自引:1,他引:1  
提出一种柴油机选择催化还原(SCR)催化器载体结构参数优化的设计方法,根据车用柴油机排量,将SCR催化器载体分为4类,选取载体体积、长度、目数、壁厚和涂层厚5个结构参数为设计变量,以高NO。转化率及低压力损失为优化目标,利用拉丁超立方实验设计选择样本点进行数值模拟,在构建的Kriging近似模型基础上,对载体结构参数采用改进的非支配排序遗传算法NSGA—II(non—dominatedsortinggeneticalgorithm—II)进行优化设计。结果表明:Kriging近似模型的拟合精度较高,结合NSGA—II算法对SCR催化器载体结构参数进行优化是可行的、有效的,不同排量下的优化结果均能够较好地满足设计要求。  相似文献   
979.
Given the growing awareness of the likely catastrophic impacts of climate change and close association of climate change with global emissions of greenhouse gases (of which carbon dioxide is more prominent) , considerable research efforts have been devoted to the analysis of carbon dioxide (CO2) emissions and its relationship to sustainable development. Now GHG reduction programs have been coming into effect in many developed countries that have more responsibility for historical CO2 emissions, and the studies have become mature. First, the GHG emissions accounting system is more all-inclusive and the methods are more rational with the effort of IPCC from 1995 and all other researchers related. Second, the responsibility allocation is more rational and fair. Along with the clarity of "carbon transfer" and "carbon leakage", the perspective and methodology for allocating regional CO2 emissions responsibility is turning from production base to consumption base. Third, the decomposition method has become more mature and more complex. For example, the decomposition formulas are including KAYA expression and input-output expression and the decomposition techniques are developed from index analysis to simple average divisia and then adaptive-weighting divisia. Fourth, projection models have become more integrated and long-term. The top-down model and bottom-up model are both inter-embedded and synergetic. Trends above give some advice for the research on CO2 in China, such as emissions factors database construction, deeper-going research on emissions responsibility and structure analysis, promotion of modeling technology and technology-environment database.  相似文献   
980.
In the present study, we aimed at determining the release of aflatoxin B1 (AFB1) and ochratoxin A (OTA) from different food products in the gastro-intestinal tract in the absence and presence of probiotics, a possible adsorbent. The average bioaccessibility of AFB1 and OTA without probiotics was about 90%, and 30%, respectively, depending on several factors, such as food product, contamination level, compound and type of contamination (spiked versus naturally contaminated). The six probiotic bacteria showed varying binding capacity to AFB1 and OTA depending on the bacterial strain, toxin studied, type of food and contamination level. A reduction to a maximum of 37% and 73% as observed for the bioaccessibility of AFB1 and OTA in the presence of probiotic bacteria, respectively. This is the first report on the effect of probiotic bacteria on reducing the fraction of mycotoxins available for absorption in the gastrointestinal tract from different food products.  相似文献   
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