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941.
942.
关注室内放射性环境污染 保护公众健康 总被引:2,自引:0,他引:2
室内的各种放射性环境污染影响人类健康,本文通过对各种室内放射性环境污染的简要评述,让人们对室内放射性环境污染有科学认识,并提出一些对策。 相似文献
943.
Lotte Holm 《Journal of Agricultural and Environmental Ethics》2003,16(6):531-544
Functional foods are a challenge tofood health policies, since they questioncentral ideas in the way that food healthpolicies have been developed over the lastdecades. Driven by market actors instead ofpublic authorities and focusing on the role ofsingle foods and single constituents in foodsfor health, they contrast traditional wisdombehind nutrition policies that emphasize therole of the diet as a whole for health.Sociological literature about food in everydaylife shows that technical rationality co-existswith other food related rationalities, such aspractical and economic rationalities, socialand relational rationalities, and symbolicrationalities that influence citizens' ordinaryeating habits. An examination of lay views onexpert knowledge about food and health showthat skepticism exists with respect to thebasis of and balance of expert advice. Critical points with respect to how functionalfoods may influence routines in the populationswith relevance for public health include thefact, that they promote a way of thinking offood and health that is in conflict withwell-established practical ways of ensuring abalanced diet. 相似文献
944.
通过济钢集团1年来建立《职业安全健康管理体系》和环境管理体系的实践,阐述了建立体系应注意的问题分析了如何把先进的国际管理体系和企业自身实际相结合,以提升管理水平并取得双认证的成功。 相似文献
945.
健康风险分析(HRA)在石化工程项目中的应用 总被引:2,自引:0,他引:2
李少鹏 《中国安全科学学报》2002,12(5):26-30
结合参加南海石化项目管理承包商 (PMC)的健康、安全、环境 (HSE)管理工作的体会 ,简要介绍了南海石化项目中使用的主要健康风险分析的方法 (HRA) ,包括HRA的意义、范围和方法 ,举例说明了如何进行HRA。同时笔者还提出了HRA和中国设计报批相结合的思路 ,指出HRA可以作为职业卫生专篇的编制依据。通过进行HRA ,找出设计中有可能影响健康的所有因素 ,确定危害部位 ,并初步提出工程控制措施和个人防护措施 ,给出了职业卫生工作在工程设计中的结合点。对今后工程中HSE一体化提供了可行的方法 相似文献
946.
947.
Salmon are perhaps the quintessential icon of the Pacific Northwest, affecting the region's culture, politics, and economy. The importance Oregonians place on salmon recovery and their willingness to pay for salmon recovery efforts was assessed biennially between 1996 and 2002 through the Oregon Population Survey. Based on these data, we found that Oregonians appear to have become less supportive toward salmon recovery and salmon recovery efforts over that time period; they were less likely to say salmon recovery is important and chose lower willingness to pay responses in 2002 than in 1996.Attitudes do appear to be related to the economic conditions and demographic composition of residents of the state. In particular, we found that local unemployment rates, age of respondent, and rural county residence are significantly negatively correlated with the respondent's expressed support for salmon recovery efforts. Attributes positively correlated with expressions of support for salmon include male gender, graduate-level education, and American Indian identity. We found that a significant portion of the decline in support is unexplained by the variables included in the analysis. 相似文献
948.
在重大工程结构健康监测中,随着研究对象复杂程度的提高,往往需要获得大量观测数据才能对结构进行有效的评估,因此采用多种或多个传感器进行测量已成为必然趋势。数据融合技术就是将多个传感器的测量结果进行综合处理,从而得出比单个传感器更为准确可靠的结果。本文基于一致性算法,提出一种改进的多传感器数据融合技术,该数据融合技术属于数据级融合,它克服了一致性算法中两传感器在测量精度不同时置信距离不同的缺点,并对支持矩阵进行模糊化处理,避免了人为定义阈值而产生的主观误差。文中通过算例,验证了此方法可获得较好的结果,并且能够有效地减小由于扰动因素造成的测量数据的变化。 相似文献
949.
This study aimed to locate VOC emission sources and characterized their emitted VOCs. To avoid interferences from vehicle exhaust, all sampling sites were positioned inside the refinery. Samples, taken with canisters, were analyzed by GC–MS according to TO-14 method. The survey period extended from Febrary 2004 to December 2004, sampling twice per season. To interpret a large number of VOC data was a rather difficult task. This study featured using ordinary application software, Excel and Surfer, instead of expensive one like GIS, to overcome it. Consolidating data into a database on Excel facilitated retrieval, statistical analysis and presentation in the form of either table or graph. The cross analysis of the data suggested that the abundant VOCs were alkanes, alkenes, aromatics and cyclic HCs. Emission sources were located by mapping the concentration distribution of these four types of VOCs in terms of contour maps on Surfer. During eight surveys, five emission sources were located and their VOCs were characterized. 相似文献
950.
An assessment of tree health and trace element accumulation near a coal-fired generating station, Manitoba, Canada 总被引:2,自引:0,他引:2
A forest health assessment was performed in stands dominated by bur oak and trembling aspen to study the potential effects of airborne emissions from a 132 MW coal-fired station. Forty-two stands were sampled within a 16-km radius of the station for both foliar stress symptoms and trace element toxicology. The concentrations of tracer elements (As, Ba, Sr, and V) in the leaf litter were not spatially congruent with airborne emission deposition models (except Ba, which showed elevated levels immediately SE of the station), nor were they at phytotoxic levels. Elemental concentrations were significantly related to soil parameters including organic matter and texture. No patterns were found in forest health along directional or distance gradients from the generating station. Trembling aspen stands demonstrated little decline in general, but three of the 19 bur oak plots, all located on thin sandy soils developed on calcareous till, demonstrated branch dieback. In addition to poor soil conditions, two of these sites also had high water tables, and exhibited tree mortality. The bur oak decline did not appear to be related to emissions from the station, but is suspected to be a result of poor site quality, with urban development as a confounding factor. 相似文献