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51.
对二甲苯( PX)是一种世界性的重要化工产品。我国是PX产品的生产大国,也是PX产品的消费大国,PX项目的发展和我国的国民经济息息相关。本文分析了二甲苯( PX)的生产概况和市场需求,论述了PX项目在我国经济发展的重要地位,论述了加快发展PX项目的必要性。本文还从环境保护的角度出发,谈论了发展PX项目的制约因素---存在着破坏环境的潜在危险等,并提出了解决方法。 相似文献
52.
文章在将中国的农村工业划分为低、中和高度污染行业的基础上,分析了农村工业各个行业增长分布和结构变化。研究发现,农村工业发展对环境的压力是趋于减缓的,东部地区农村工业各个行业的份额在全国都居于主导地位,而且还保持着较快的增长速度,因此,全国农村工业污染治理的重点要放在东部地区。从区域内部来看,东部地区农村工业的低污染行业增长速度最快,高度污染行业下降的速度较慢;中部和西部地区的低污染行业增长较快,但同时高度污染行业也保持着较高的增长速度。因此,这两个区域更重要的是要降低高度污染行业的增长速度。 相似文献
53.
Many problems arise in connection with the communication of risk information. In this article the content of the information communicated is taken as a starting-point for analyzing the risk communication process. We studied the way in which authorities communicated health risks to local residents in Dutch soil pollution situations and found that communication problems were characterized more by misunderstanding and conflict between parties with different views and interests than by a lack of understanding. Therefore, it is important to look more closely at the way the communicators of information (in our cases, officials) select risk information from risk assessments, and to study the effects that the information selected has on the receivers (in our cases, residents). Both the process of selection by the officials and the process of interpretation by the residents will be shown to be influenced by the different institutional backgrounds. The article presents a new approach to risk communication. Both the risk information presented by the authorities and the public reactions to this risk information are considered to reflect the institutional background of authorities and residents, and can be analyzed in these terms. Such an approach has consequences for the study of risk communication and the manner in which it is practiced. 相似文献
54.
Bart David Ostro 《Risk analysis》1989,9(2):189-196
Five years of the annual Health Interview Survey, conducted by the National Center for Health Statistics, are used to estimate the effects of air pollution, smoking, and environmental tobacco smoke on respiratory restrictions in activity for adults, and bed disability for children. After adjusting for several socioeconomic factors, the multiple regression estimates indicate that an independent and statistically significant association exists between these three forms of air pollution and respiratory morbidity. The comparative risks of these exposures are computed and the plausibility of the relative risks is examined by comparing the equivalent doses with actual measurements of exposure taken in the homes of smokers. The results indicate that: (1) smokers will have a 55-75% excess in days with respiratory conditions severe enough to cause reductions in normal activity; (2) a 1 microgram increase in fine particulate matter air pollution is associated with a 3% excess in acute respiratory disease; and (3) a pack-a-day smoker will increase respiratory restricted days for a nonsmoking spouse by 20% and increase the number of bed disability days for young children living in the household by 20%. The results also indicate that the estimates of the effects of secondhand smoking on children are improved when the mother's work status is known and incorporated into the exposure estimate. 相似文献
55.
通过盆栽试验研究了Cd、Pb单一污染对龙须草生长全期干物质积累的影响。结果表明,在成熟期以前,Cd、Pb低浓度(不高于5mgCd/kg土)刺激能够促进龙须草植株干物质积累,高浓度(不低于200mgPb/kg土)刺激对龙须草干物质积累有抑制作用。被Cd、Pb污染的龙须草在成熟期时干物质积累总量比前一时期略微减小。Cd、Pb的临界浓度分别为5mgCd/kg土和200mgPb/kg土,表明龙须草干物质积累对Cd污染较Pb污染敏感。 相似文献
56.
Symmetry and separability of a covariance function are common assumptions to simplify the modeling effort of spatial–temporal processes. However, many studies in environmental sciences show that real data have complex spatial–temporal dependency structures resulting from lack of symmetry or violation of other standard assumptions of the covariance function. In this study, we propose new formal tests for lack of symmetry by using spectral representations of the spatial–temporal covariance functions of regularly spaced spatial–temporal data. The advantage of the proposed tests is that classical analysis of variance (ANOVA) models can be used for detecting lack of symmetry inherent in spatial–temporal processes. We evaluate the performance of the tests with simulation studies and we apply them to air pollution data. 相似文献
57.
Health Risks of Energy Systems 总被引:1,自引:0,他引:1
Wolfram Krewitt Fintan Hurley Alfred Trukenmüller Rainer Friedrich 《Risk analysis》1998,18(4):377-383
Health risks from fossil, renewable and nuclear reference energy systems are estimated following a detailed impact pathway approach. Using a set of appropriate air quality models and exposure-effect functions derived from the recent epidemiological literature, a methodological framework for risk assessment has been established and consistently applied across the different energy systems, including the analysis of consequences from a major nuclear accident. A wide range of health impacts resulting from increased air pollution and ionizing radiation is quantified, and the transferability of results derived from specific power plants to a more general context is discussed. 相似文献
58.
何宇霏 《安徽农业大学学报(社会科学版)》2015,24(5):24-28,91
改革开放三十年,我国经济突飞猛进,但严重的环境污染与生态破坏问题也随之而来.按照经济学理论,运用经济手段保护环境较传统方式更具优势.世界环境保护的发展实践用事实证明,构建环境税法律制度是解决我国当前环境保护困局的有效办法.基于现行的排污收费制度奠定的良好基础和国外开征环境税的丰富经验,我国建立环境税法律制度已具有现实可能性.汲取我国环境保护制度的经验教训,环境税不能变成政府增加其财政收入的工具,其征税对象、税率设定、征收管理等方面的设计均要体现解决环境问题、保护生态环境的设立初衷. 相似文献
59.
环境传播并非仅是环境议题的扩散,更是各种主体的话语呈现。土壤污染报道可以作为探讨环境传播中话语表征的典型案例。分析2013年1月1日至2013年12月31日期间的746篇报纸媒体土壤污染报道样本,发现:土壤污染报道中政府、专家、企业、NGO以及公众各方的话语权并不平等,其中政府占据议题的主要话语权,专家学者积极介入议题报道,企业则表现为回避突发土壤污染事件。相较于前三者的强势话语权地位,环保NGO和公众的话语权较为弱势。 相似文献
60.
运用计量地理学相关分析的方法,以石家庄市2009年12月~2011年1月数据为例,研究大气颗粒物与能见度变化的相关性.研究结果显示:相对湿度与大气能见度呈显著负相关,与颗粒物质量浓度相关性较差;大气颗粒物质量浓度与能见度之间呈负相关,[0.43,0.65)μm粒径范围内二者相关性较显著. 相似文献