Electronic standards for the calibration of pollution monitoring equipment

In order to calibrate the electronic portion of pollution monitoring equipment, it is desirable to have electronic standards that operate over the range covered by the primary detectors. This paper describes active standards of current, voltage and resistance, directly related to this type of equipment. In addition to this, methods are discussed by means of which these standards may be used effectively. The paper concludes with the concept of the specific source characterization of electricity in support of active standards.     

天空颜色与大气污染

自然界中绚丽多彩的晚霞和日出东方时的壮丽景象,是任何一位艺术家都难以描绘的.但是,很少有人知道,我们如今目睹的大部分颜色是污染造成的.城市的落日和空气清新的乡村落日是不同的. 在非常洁净、未受污染的大气中,落日的颜色特点鲜明.太阳是灿烂的黄色,同时邻近的天空呈现出橙色和黄色.当落日缓缓地消失在地平线下面时,天空的颜色便逐渐从橙色变为蓝色.即使太阳消失以后,贴近地平线的云层仍会继续反射着太阳的光芒.因为天空的蓝色和云层反射的红色太阳光融合在一起,所以较高天空中的薄云呈现出红紫色.     

机动车火灾分析及预防

机动车是现代社会使用最广泛最便捷的交通工具.随着我国经济建设和交通运输事业的飞速发展,机动车运输业已成为国家经济命脉的生命线之一.近几年,机动车火灾发生起数上升较快,从宏观上分析原因大致有以下几点:首先,机动车数量迅速增长.据统计,新中国成立以来,从1949年到1996年的48年里,北京市机动车仅有98万辆,而从1996年到2005年10年的时间里,全市机动车数量增加了160.3万辆,达到258.3万辆,截至2009年12月,全市机动车数量已达到400万.     

Intense winter atmospheric pollution episodes affecting the Western Mediterranean

The geographic location of the Western Mediterranean Basin and its peculiar topography, the climatic conditions and the intense anthropogenic and natural emissions of atmospheric pollutants are key factors necessary to interpret the atmospheric aerosol phenomenology over this area. During the cold season it is common to have severe atmospheric particulate matter (PM) pollution episodes (of an anthropogenic origin) affecting this region, not only in the urban and industrial areas but also in the regional and rural sites. During these episodes, the midday hourly PM₁ levels at regional background sites are in many cases higher than those at urban areas. Around 10% of the days under winter anticyclonic conditions registered similar PM₁ levels at the regional background than at the urban area and, sporadically the daily PM₁ levels at the regional background sites may exceed those at urban sites. Furthermore, the very high hourly PM₁ levels measured at regional background sites during these episodes are not regularly attained in the closest urban areas, which leads to the hypothesis that an important formation of secondary aerosols occurs during the transport of the polluted air masses towards the elevated rural sites.The interpretation of the variability of PM levels and composition (2002-2008) at one urban site (Barcelona) and at one regional background site (Montseny) allows us to illustrate the phenomenology of these scenarios, to quantify the mean annual contributions to the PM levels and to identify their main tracers. Ammonium nitrate appears to be the most abundant compound during these scenarios, although organic species and trace metals also increase markedly. Owing to the intensity, composition and recurrence of these atmospheric pollution episodes, important health, climatic and ecological implications may be derived.     

建筑工程对大气环境污染的影响与控制

对建筑工程中常见的颗粒污染物、气态污染物等进行了论述,分析了建设工程对空气污染的危害,提出了建筑工地空气污染的预防及治理方法,从而有效地减少空气污染。     

南海饮用水水源突发性污染应急处理系统的研发和建立

针对水源突发性污染频发的现状,开发和建立了南海饮用水水源突发性污染应急处理系统。在对北江水源地存在的污染物进行调查分析并确定目标污染物的基础上,研究了目标污染物的应急去除技术,建立水源水质预警系统和水厂应急强化处理系统。介绍了项目实施的技术思路以及取得的主要技术成果,可为同行业其他企业提供参考。     

Stable lead isotopes and lake sediments--a useful combination for the study of atmospheric lead pollution history

Analysis of stable lead isotopes and lead concentrations in lake-sediment deposits, not least in varved (annually-laminated) sediments, is a useful method to study lead pollution history. This paper presents details from a study of 31 lakes in Sweden. Using a strong acid digestion of sediment samples and ICP-MS analyses, we have found that Swedish lake sediments have a high natural (pre-pollution) 206[Pb]207[Pb] ratio (mean 1.52+/-0.18, range 1.28-2.01, n=31 lakes). In contrast, atmospheric lead pollution derived from metal smelting processes, coal burning and from alkyl-lead added to petrol has a lower ratio (< 1.2). Consequently, when pollution lead deposition began approximately 3500 years ago, the lead isotope ratio of the sediments started to decline, and in modern sediments it is typically < 1.2. Using the isotope and concentration values and a mixing model, the relative contribution of pollution and natural lead in sediment samples can be calculated. The pollution lead records of the Swedish lake sediments show a consistent picture of the atmospheric lead pollution history. Some noticeable features are the Roman peak (approx. 0 AD), the large and permanent Medieval increase (approx. 1000 AD), peaks at approximately 1200 and 1530 AD, the rapid increase after World War II, the peak in the 1970s, and the large modern decline.     

Seasonal pollution characteristics of organic compounds in atmospheric fine particles in Beijing

Beijing is a rapidly developing city with severe and unique air pollution problems. Organic matter is the most abundant fraction in fine particles in Beijing, occupying 30-50% of the total mass, indicating its key role in air pollution control. However, detailed chemical characterization of particulate organic matter in Beijing has never been reported. In this study, fine particles in the urban atmosphere in Beijing were investigated for its organic components by GC/MS technique. Over 100 individual organic compounds were identified and quantified in 25 PM2.5 samples from the summer, autumn and winter of 2002-2003. Alkanes, fatty acids, dicarboxylic acids, polycyclic aromatic hydrocarbons and some important tracer compounds (hopanes, levoglucosan and steroids) were the major constituents with the sum of their concentrations of 502, 1471 and 1403 ng m(-3) in summer, autumn and winter, respectively. Different organic compounds presented apparently different seasonal characteristics, reflecting their different dominant emission sources, such as coal combustion, biomass burning and cooking emission. The abundance and origin of these organic compounds are discussed to reveal seasonal air pollution characteristics of Beijing.     

城市水污染控制和水环境综合整治标准建立

就城市水污染控制和综合整治的背景,以及建立的必要性和可行性进行了相关的研究,阐述了体系的建立基础与依据,提出了对城市水污染进行控制以及综合整治的控制措施,并对标准体系以及控制的关系进行了分析,对水污染的治理有重要的意义。     

Critical levels of atmospheric pollution: criteria and concepts for operational modelling of mercury in forest and lake ecosystems

Mercury (Hg) is regarded as a major environmental concern in many regions, traditionally because of high concentrations in freshwater fish, and now also because of potential toxic effects on soil microflora. The predominant source of Hg in most watersheds is atmospheric deposition, which has increased 2- to >20-fold over the past centuries. A promising approach for supporting current European efforts to limit transboundary air pollution is the development of emission-exposure-effect relationships, with the aim of determining the critical level of atmospheric pollution (CLAP, cf. critical load) causing harm or concern in sensitive elements of the environment. This requires a quantification of slow ecosystem dynamics from short-term collections of data. Aiming at an operational tool for assessing the past and future metal contamination of terrestrial and aquatic ecosystems, we present a simple and flexible modelling concept, including ways of minimizing requirements for computation and data collection, focusing on the exposure of biota in forest soils and lakes to Hg. Issues related to the complexity of Hg biogeochemistry are addressed by (1) a model design that allows independent validation of each model unit with readily available data, (2) a process- and scale-independent model formulation based on concentration ratios and transfer factors without requiring loads and mass balance, and (3) an equilibration concept that accounts for relevant dynamics in ecosystems without long-term data collection or advanced calculations. Based on data accumulated in Sweden over the past decades, we present a model to determine the CLAP-Hg from standardized values of region- or site-specific synoptic concentrations in four key matrices of boreal watersheds: precipitation (atmospheric source), large lacustrine fish (aquatic receptor and vector), organic soil layers (terrestrial receptor proxy and temporary reservoir), as well as new and old lake sediments (archives of response dynamics). Key dynamics in watersheds are accounted for by quantifying current states of equilibration in both soils and lakes based on comparison of contamination factors in sediment cores. Future steady-state concentrations in soils and fish in single watersheds or entire regions are then determined by corresponding projection of survey data. A regional-scale application to southern Sweden suggests that the response of environmental Hg levels to changes in atmospheric Hg pollution is delayed by centuries and initially not proportional among receptors (atmosphere > soils not equal sediments>fish; clearwater lakes > humic lakes). This has implications for the interpretation of common survey data as well as for the implementation of pollution control strategies. Near Hg emission sources, the pollution of organic soils and clearwater lakes deserves attention. Critical receptors, however, even in remote areas, are humic waters, in which biotic Hg levels are naturally high, most likely to increase further, and at high long-term risk of exceeding the current levels of concern: 相似文献   

汽车制造厂焊接车间污染源放散与控制的研究

对某焊接车间的污染源进行了测试,并模拟了两种通风形式下车间的浓度场、温度场和速度场,得到了该车间最佳的节能通风空调形式.     

Geochemical evidence for atmospheric pollution derived from prehistoric copper mining at Copa Hill,Cwmystwyth, mid-Wales,UK

This paper presents geochemical data from a blanket peat located close to a Bronze Age copper mine on the northern slopes of the Ystwyth valley, Ceredigion, mid-Wales, UK. The research objective was to explore the possibility that the peat contained a geochemical record of the pollution generateD by mining activity. Four peat monoliths were extracted from the blanket peat to reconstruct the pollution history of the prehistoric mine. Three different geochemical measurement techniques were employed and four copper profiles have been reconstructed, two of which are radiocarbon-dated. The radiocarbon dates at one profile located close to the mine confirm that copper enrichment occurs in the peat during the known period of prehistoric mining. Similar enrichment of copper concentrations is shown in one adjacent profile and a profile within 30 m away. In contrast, copper was not enriched in the other radiocarbon-dated monolith, collected approximately 1.35 km to the north of the mine. Whilst other possible explanations to explain the copper concentrations are discussed, it is argued that the high copper concentrations represent evidence of localised atmospheric pollution caused by Bronze Age copper mining in the British Isles. The results of this study suggest that copper may be immobile in blanket peat and such deposits can usefully be used to reconstruct atmospheric pollution histories in former copper mining areas.     

Relation between atmospheric pollution, precipitation, and streamwater quality near a large urban-industrial complex

An investigation was made of the effects of atmospheric effluents from a large urban-industrial area (St. Louis) on the water quality in two small basins that are frequently downwind of the city. Analyses were made of the relative magnitude of the atmospheric contribution to streamwater pollution, and how this contribution is related to weather conditions. Field sampling was done during a 15-month period, and investigation made of atmospheric-streamwater relationships for storm, seasonal, and annual periods. Computations were made for 12 chemical constituents in the rainwater and streamwater. Results indicated that only minor changes usualy occur in streamwater pollutant concentrations during and shortly following storms, and no strong relationship exists between streamwater concentration and weather conditions. For most pollutants the atmospheric deposition was small compared with the annual stream load because of major surface sources. However, evidence was also found that urban-industrial sources can occasionally be important contributors to stream contamination.     

使机动车污染物排放量为最优的信号配时方法

提出了以信号交叉口交通污染物排放量最优为目标的信号配时模型,以南京市的一个信号交叉口实例进行最优化信号配时模型的应用分析,得出了此信号配时模型在满足一定服务水平下可以算出交叉口机动车污染物排放量最优的信号周期时长和绿灯时间。     

浅谈住宅套型设计

从户型与套型混为一谈的现象入手,引出户型与套型的概念及相互关系,并通过对居民家庭类型的实际分析,阐述了户型对套型的影响及针对户型进行套型设计的方法与途径。     

标准调研势在必行

本文通过对标准化工作的调研,发现在标准化管理当中存在许多具体问题,针对这些问题作为标准化管理部门应采取的对策及标准化的发展战略.     

工程车辆电液自动调平系统

介绍一种适用于工程车辆的电液自动调平系统，着重分析其工作原理及调平传感器的结构和液压系统的设计。     

密封材料标准发展现状

介绍了国外密封材料标准发展现状,特点及新进展,分析了国内标准水平,存在差距,提出了改进的建议。