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采用中流量颗粒物采样器采集了60个可吸入颗粒物(PM10)环境样品,并用离子色谱法(IC)对所采集样品中的8种水溶性离子组成特征进行了分析。结果显示,春季南充城区空气质量良好,PM10中8种水溶性离子浓度大小为SO2-4NO-3Ca2+Na+Cl-K+F-Mg2+。其中SO2-4、NO-3和Ca2+的平均质量浓度分别占总水溶性无机离子(TWSII)的62.4%、23.9%和4.7%。NO-3和SO2-4及Ca2+和Mg2+具有良好的相关关系,燃煤源对PM10的贡献大于机动车移动排放源的贡献;水溶性无机离子主要以NaCl、MgSO4和Mg(NO3)2的形式存在。 相似文献
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深圳市近年来环境空气质量情况及主要影响因素分析研究 总被引:1,自引:0,他引:1
根据深圳10个国控监测点位大气自动监测数据以及自然、地理、经济、社会等相关情况,借助Spearman秩相关系数法、环境库兹涅茨曲线等方法,对深圳近年来环境空气质量及影响因素进行了分析。结果表明深圳环境空气质量总体保持较好水平,自2006年以来呈改善的趋势,机动车、电厂、港口码头、工业则是深圳大气污染的主要来源,优化的经济结构、下垫面组分类型多样等城市下垫面特征等均对环境空气质量改善起到一定的作用。 相似文献
535.
大气颗粒物源解析CMB法与PFA法原理及比较研究 总被引:1,自引:0,他引:1
大气颗粒物已经成为中国许多大中城市的首要空气污染物.弄清楚大气颗粒物的来源及定量地计算出各个源的贡献值,为颗粒污染物的防治提供依据,这就涉及到大气颗粒物源解析技术.本文详细介绍了化学质量平衡(CMB)和主因子分析法(PFA)这两种主要的大气颗粒物源解析原理及方法,并比较两种方法各自的优缺点,以供选择合适的源解析方法对大气颗粒污染物的来源进行解析. 相似文献
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研究温压炸药爆炸初期弹内爆炸波作用过程,可以进一步分析温压炸药分散爆轰的作用机理,为温压炸药武器设计和系统优化提供可靠依据.设计了用测时法研究温压炸药爆轰波传播速度的试验装置,并用探针对相同组分和密度条件下、温压战斗部弹内爆炸初期的爆炸作用过程进行了对比试验,记录了触发时间信号,计算并分析了温压炸药弹内爆炸波的传播特性,得到了波阵面与弹径方向夹角α的变化规律.试验结果表明,温压炸药的爆轰波传播速度为4.632km/s,其弹内爆轰波的传播特性与中心高能分散药的爆轰波有密切联系,通过合理设计弹体结构和比药量,可以实现温压炸药的分散爆轰,提高温压炸药的爆炸威力. 相似文献
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- DOI: http://dx.doi.org/10.1065/espr2006.02.294
Background, Aim and Scope. To better address the requirements of the changing multilateral order, the United Nations Industrial
Development Organization (UNIDO) Cleaner Production Programme, in 2004, developed the new Sustainable Industrial Resource
Management (SIRM) approach. This approach is in accordance with the principles decided at the United Nations Conference on
Environment and Development (UNCED) in Rio de Janeiro, Brazil in 1992. Unlike the traditional approaches to environmental
management, the SIRM concept captures the idea of achieving sustainable industrial development through the implementation
of circular material and energy flows in the entire production chain and reduction of the amount of material and energy used
with greater efficiency solutions. The SIRM approach seeks to develop new models to encourage a shift from selling products
to supplying services, modifying, in this manner, the supplier/user relationship and resulting in a win-win situation for
the economy and the environment. Chemical Leasing represents such a new service-oriented business model and is currently being
promoted by UNIDO′s Cleaner Production Programme.
Main Features. One of the potential approaches to address the problems related to ineffective use and over-consumption of
chemicals is the development and implementation of Chemical Leasing business models. These provide concrete solutions to the
effective management of chemicals and on the ways negative releases to the environment can be reduced. The Chemical Leasing
approach is a strategy that addresses the obligations of the changing international chemicals policy by focusing on a more
service-oriented strategy. Mexico is one of the countries that were selected for the implementation of UNIDO's demonstration
project to promote Chemical Leasing models in the country. The target sector of this project is the chemical industry, which
is expected to shift their traditional business concept towards a more service and value-added approach. This is being achieved
through the development of company specific business models that implement the above-indicated Chemical Leasing concept with
the support from the Mexican National Cleaner Production Centre (NCPC).
Results and Conclusions. The implementation of Chemical Leasing in Mexico has proven to be an efficient instrument in enhancing
sustainable chemical management and significantly reducing emissions in Mexico. Several companies from the chemical industrial
sector implement or agreed to implement chemical leasing business models. Based on the positive findings of the project,
several Mexican companies started to negotiate contents of possible Chemical Leasing contracts with suitable business partners.
The project further aimed at disseminating information on Chemical Leasing. It successfully attracted globally operating companies
in the chemicals sector to explore possibilities to implement Chemical Leasing business models in Mexico. At the international
level, the results of the UNIDO project were presented on 20TH September 2005 during a side event of the Strategic Approach
to International Chemicals Management (SAICM) Preparation Conference in Vienna.
Recommendations and Outlook. To facilitate the promotion and application of Chemical Leasing project at international level,
UNIDO is currently developing a number of tools to standardize Chemical Leasing projects. These include, among others, Chemical
leasing contract models; Chemical Leasing data base to find partners for chemical leasing; and guidelines to implement Chemical
Leasing projects and work programmes. 相似文献
540.
Jaïro Falla Philippe Laval-Gilly Michel Henryon Dominique Morlot Jean-françois Ferard 《Environmental monitoring and assessment》2000,64(3):627-644
Air quality monitoring is currently ensured by captors measuring few physicochemical parameters, then they cannot evaluate unforeseen compounds and the interaction effects of pollutants. On the contrary, the use of bioindicators can answer these problems. Among them, plants are used in two ways:1) Passive bioindicators: trees, lichens and mosses are used to determine the distribution and even the contaminants long-term effects on vast zones and, possibly, the concentrations of pollutants to which they were exposed.2) Active bioindicators: tobacco and mosses make available the defective zones in plants and enable determination of deposition fluxes.Moreover, techniques based on biomarkers identification should increase the answer's sensitivity. However, the plants present the disadvantage of being unable to provide a response in a time lapse comparable with that of the on-line analysers. Lastly, the development of tools using animal cells should allow, in the near future, to measure the total polluting load under conditions close to those of the routine techniques. Then, the real impact of the contaminant on public health could be approached. 相似文献