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991.
Background, aim, and scope  It has been known that the pollutants of electronic wastes (E-wastes) can lead to severe pollution to the environment. It has been reported that about 50% to 80% of E-wastes from developed countries are exported to Asia and Africa. It has become a major global environmental problem to deal with ‘E-wastes’. E-waste recycling has remained primitive in Jinghai, China. This not only produces enormous environmental pollution but also can bring about toxic or genotoxic effects on the human body, threatening the health of both current residents and future generations living in the local environment. The concentration of lead in the blood of children in the E-waste polluted area in China is higher than that of the control area. But little is known about the cytogenetic effect to human beings caused by the pollution of E-wastes. In the present study, experiments have been performed to investigate the genetics of permanent residents of three villages with numerous E-waste disposal sites and to analyze the harmful effects of exposure to E-wastes. Materials and methods  In total, 171 villagers (exposed group) were randomly selected from permanent residents of three villages located in Jinghai County of Tianjin, China, where there has been massive disposal of E-wastes. Thirty villagers were selected from the neighboring towns without E-waste disposal sites to serve as controls. Chromosomal aberrations and cytokinesis blocking micronucleus were performed to detect the cytogenetic effect, dic + r (dicentric and ring chromosome), monomer, fragments (acentric fragments, minute chromosomes, and acentric rings), translocation, satellite, quadriradial, total aberrations, and micronuclear rate were scored for each subject. DNA damage was detected using comet assay; the DNA percentage in the comet tail (TDNA%), tail moment (TM), and Olive tail moment (OTM) were recorded to describe DNA damage to lymphocytes. Results  The total chromosome aberration rates (5.50%) and micronuclear rates (16.99%) of the exposure group were significantly higher than in the control group (P = 0.000). The percentage of DNA in the comet tail, tail moment, and Olive tail moment detected by comet assay showed that there was a significant difference in DNA damage in the exposure group (P = 0.000). The chromosome aberration, micronucleus rate, and DNA damage observed in women were significantly higher than those in men. Chromosome aberration and micronuclear rates of both smokers and non-smokers in the exposure group are obviously higher than that in the control group (P = 0.000). Discussion  The use of outdated (and unsafe) ways to deal with E-wastes can lead to exposure to a variety of substances harmful to human health. The components of pollution may enter the human body through the air, drinking water, and food chain to damage human genetic material, resulting in genomic instability. The rates of chromosomal aberration, micronucleus formation, and the degree of DNA damage in women in the group exposed to electronic waste were significantly higher than in men. The reason for this may be concerned with the traditional lifestyle of the local residents or the difference of sensitivity to the exposure to E-wastes or any others. Further investigations are needed to provide evidence to demonstrate this. Conclusions  Here, we report the obviously cytogenetic toxicity to the exposure population by the E-waste pollution for the first time. E-waste pollution may be a potential agent of genetic mutation, and may induce cytogenetic damage within the general population exposed to the pollution. These findings need to be considered, and steps should be taken to protect the current population and future generations from the effects of pollution with E-wastes. Recommendations and perspectives  The above results remind us that the impact of E-waste recycling on environmental quality of Jinghai should be evaluated soon. Moreover, it is urgent for the government to prohibit E-waste import and its processing by outdated ways. The future studies such as pollutant details of drinking water, air, and soil in the area as well as epidemiological investigations on the harmful effect to children must be performed eagerly. All the data available do provide a compelling case for immediate action in both countries to address workplace health and safety and waste management. Qiang Liu and Jia Cao contributed equally to this study and share the first authorship.  相似文献   
992.
古建筑的消防安全工作作为古建筑保护工作内容的重要组成部分,需要深入开展的消防科学的研究工作.目前在我国,缺少关于古建筑防火安全方面的规范,通常使用的处方式规范一般不适用于古建筑.性能化方法能够提供更加灵活和符合实际的解决方案.并且这可能是唯一可行的使古建筑达到可接受风险水平的方法.以布达拉宫东大殿为研究对象,探讨了性能化防火分析方法在古建筑防火保护中的应用.以对古建筑进行早期探测报警为目标进行了消防设施设置.应用FDS软件进行了模拟研究,根据模拟结果进行分析,得到了一些有益的结论并应用于消防设施设置.通过对探测器响应时间分析,探测器的设置合理,能够在第一时间报警,并且实现了消防安全设计的科学化、合理化和成本效益的最优化.  相似文献   
993.
作为特大型城市,上海2008年常住人口总量已达1 888万,城市化水平也以87%高居全国首位.通过分析上海1978-2008年30年来人口变化特征及其资源环境效应表明,伴随着人口规模不断扩大和城市化水平快速提升,2008年上海居民生活电耗和水耗分别是1978年的17倍和5倍,占资源消费总量的比例也逐年快速攀升;生活废水排放量已取代工业废水成为最大贡献源,占废水排放总量的比例高达80%;生活废气排放总量相对稳定.针对上海实现可持续发展所面临的人口难题,从依据人口发展规律调整城市发展战略,通过产业结构调整带动经济增长方式转变,切实加大环保投入力度促进治污防污,进一步提高公众环保意识和企业环保责任等几个方面提出了破解这一难题的对策与建议.  相似文献   
994.
Responsive accommodation is a political strategy that addresses concerns about a policy proposal by incorporating amendments that address those concerns. This approach can broaden the policy’s appeal, but is strategically risky, as it can alienate the policy’s base of support. We examine this strategy and its application in the politics of climate change. Using a novel survey experiment, relative public support is evaluated for two amendments to a carbon tax proposal – revenue neutrality assurances and a carbon tariff – designed to ease concerns about taxes and global competitiveness. Analysis shows that support for a carbon tax increases when coupled with a carbon tariff, but decreases among some of the policy’s supporters when described as revenue-neutral. These results suggest that policymakers using a responsive accommodation strategy must carefully weigh its possible risks and rewards in their particular context.  相似文献   
995.
Studies have shown that pleasant scents favor positive social relationships. However, the effect of pleasant ambient odor on romantic relationships has never been tested. In a field experiment, 18–25 year old women walking alone in a shopping mall were approached by an attractive 20 year old male-confederate who solicited them for their phone number. The women were solicited as they were walking in areas with pleasant ambient odors (e.g., pastries) or with no odor. It was found that women agreed more often to the confederate's courtship solicitation in the pleasant smelling areas. Positive mood induced by ambient odors may explain such results.  相似文献   
996.
全利  余恒  王晓波 《四川环境》2012,31(6):101-106
根据"十一五"期间和2011年四川省省控城市环境空气质量监测数据,在比较新、旧环境空气质量标准不同的基础上,本文分析了修订后的《环境空气质量标准》对四川省城市环境空气质量评价结果的影响。  相似文献   
997.
This article sets out to evaluate the range of meanings and preferences for the concepts of adaptation, resilience, mitigation and coping of a variety of professionals in New York who are undertaking leadership positions in developing climate change policies and practices. This article positions a normative set of simplified meanings for each of the aforementioned concepts based on a review of existing literature. Utilizing a survey, these normative meanings are evaluated by and between the: (a) concepts and meanings; (b) concepts and applications and (c) applications and preferences, as applied to various risk-based scenarios ranging from sea-level rise to heat waves. This survey tests the hypotheses that the respondents: (i) are unable to consistently match the concept of resiliency with the normative meanings or applications: and (ii) will not consistently show a preference for resilience applications or outcomes ahead of other concepts. The results of the survey confirm both hypotheses, which is demonstrative of the inadequacy of the current framework dominated by a narrowly defined framework for resilience. It is anticipated that the results of this article will advance an argument for the necessity to develop consistent meanings for concepts which bridge the scientific, policy and popular domains.  相似文献   
998.
The recent developments in manufacturing organizations recognize sustainability as an important value addition for survival in the competitive scenario. The design engineers are in search of approaches for creating environmental conscious products. The purpose of this paper is to report a research carried out for ensuring sustainable product design by the integration of Design for Environment (DFE) and Design for Manufacture and Assembly (DFMA) methodologies. In this context, this paper reports a case study carried out in an automotive component. The candidate product is the charge alternator pulley. The existing pulley has been created using Computer Aided Design. Then sustainability analysis was conducted on the existing component for determining environmental impact. This is followed by the engineering analysis of the component using ANSYS. Then conceptual design changes were developed in the proposed product using DFMA concept. Then the environmental impact has been evaluated in terms of carbon footprint, energy consumption and air/water impacts on proposed product. It has been found that the optimized pulley design possesses minimal environmental impact. The result of the case study indicated that the integration of DFE and DFMA concept could initiate new developments in sustainable designs with minimal impact to the environment and it also reduces the product cost.  相似文献   
999.
A method employing solid phase extraction followed by gas chromatography-mass spectrometry with negative chemical ionization has been developed for determination of ultratrace concentrations of perfluoroalkyl carboxylic acids in river water. The effects of the experimental parameters, such as the pH, additions of NaCl and an ion-pairing agent (tetraethylammonium bromide) and the kind of the elution agent, on the efficiency of the test acid extraction have been studied. The analyte extraction recoveries and the limits of detection and determination have been found. The method developed has been tested on determinations of perfluoroalkyl carboxylic acids in the waters of the two largest Czech rivers, Vltava and Labe (Elbe). The best extraction results have been attained without any alteration of the sample pH, with an addition of tetrabutylammonium bromide (a concentration of 50 μg mL−1 in the sample) and using methanol as the elution agent. Under these conditions, the recoveries of the test acids in the spiked real samples are within ranges from 60% to 104% and 53% to 111% for analyte concentration levels of 1.40 ng mL−1 and 0.14 ng mL−1, respectively, depending on the lengths of the perfluorinated chains of the acids. In general, the recovery decreases with increasing length of this chain. The method developed exhibits very low limits of detection and determination and the results are fully comparable with those obtained when using more expensive HPLC-MS/MS instrumentation. Typical values amount to tenths to tens of pg mL−1 and units to one hundred pg mL−1 for the limits of detection and determination, respectively; the measuring sensitivity increases with increasing length of the analyte chain. The analyzes of real samples from the Vltava and Elbe rivers have demonstrated that the results obtained are similar to the values published for contamination of the Elbe and other rivers in western and central Europe. The concentrations determined are of the order of units to tens of pg mL−1 and the C8-C10 acids occur most often.  相似文献   
1000.
Volatile organic compounds at swine facilities: A critical review   总被引:3,自引:0,他引:3  
Ni JQ  Robarge WP  Xiao C  Heber AJ 《Chemosphere》2012,89(7):769-788
Volatile organic compounds (VOCs) are regulated aerial pollutants that have environmental and health concerns. Swine operations produce and emit a complex mixture of VOCs with a wide range of molecular weights and a variety of physicochemical properties. Significant progress has been made in this area since the first experiment on VOCs at a swine facility in the early 1960s. A total of 47 research institutions in 15 North American, European, and Asian countries contributed to an increasing number of scientific publications. Nearly half of the research papers were published by U.S. institutions.Investigated major VOC sources included air inside swine barns, in headspaces of manure storages and composts, in open atmosphere above swine wastewater, and surrounding swine farms. They also included liquid swine manure and wastewater, and dusts inside and outside swine barns. Most of the sample analyses have been focusing on identification of VOC compounds and their relationship with odors. More than 500 VOCs have been identified. About 60% and 10% of the studies contributed to the quantification of VOC concentrations and emissions, respectively. The largest numbers of VOC compounds with reported concentrations in a single experimental study were 82 in air, 36 in manure, and 34 in dust samples.The relatively abundant VOC compounds that were quantified in at least two independent studies included acetic acid, butanoic acid (butyric acid), dimethyl disulfide, dimethyl sulfide, iso-valeric, p-cresol, propionic acid, skatole, trimethyl amine, and valeric acid in air. They included acetic acid, p-cresol, iso-butyric acid, butyric acid, indole, phenol, propionic acid, iso-valeric acid, and skatole in manure. In dust samples, they were acetic acid, propionic acid, butyric acid, valeric acid, p-cresol, hexanal, and decanal. Swine facility VOCs were preferentially bound to smaller-size dusts.Identification and quantification of VOCs were restricted by using instruments based on gas Chromatography (GC) and liquid chromatography (LC) with different detectors most of which require time-consuming procedures to obtain results. Various methodologies and technologies in sampling, sample preparation, and sample analysis have been used. Only four publications reported using GC based analyzers and PTR-MS (proton-transfer-reaction mass spectrometry) that allowed continuous VOC measurement. Because of this, the majority of experimental studies were only performed on limited numbers of air, manure, or dust samples. Many aerial VOCs had concentrations that were too low to be identified by the GC peaks.Although VOCs emitted from swine facilities have environmental concerns, only a few studies investigated VOC emission rates, which ranged from 3.0 to 176.5 mg d−1 kg−1 pig at swine finishing barns and from 2.3 to 45.2 g d−1 m−2 at manure storages. Similar to the other pollutants, spatial and temporal variations of aerial VOC concentrations and emissions existed and were significantly affected by manure management systems, barn structural designs, and ventilation rates.Scientific research in this area has been mainly driven by odor nuisance, instead of environment or health concerns. Compared with other aerial pollutants in animal agriculture, the current scientific knowledge about VOCs at swine facilities is still very limited and far from sufficient to develop reliable emission factors.  相似文献   
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