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71.
Lichen–soil column samples were taken from several locations in the Southern Finland between 1986 and 2006. Columns were divided into three parts, upper lichen, lower lichen and underlying soil, and their gamma emitting radionuclides, 134Cs, 137Cs, 103Ru, 95Zr, 106Ru, 110mAg, 125Sb and 144Ce, were measured with gamma spectrometry. Deposition values were calculated as Bq/m2 for each sampling site. Distribution of various radionuclides in the three compartments as a function of time was determined. Both effective and ecological half-lives of all radionuclides were calculated for upper lichen, whole lichen and whole lichen–soil column. A linear relation was derived between the physical half-lives and effective half-lives for whole lichen and for whole lichen–soil column. Reindeer meat activity concentrations of various radionuclides and ensuing radiation doses to reindeer-herding people were also estimated for a hypothetical case where a similar high radioactive pollution, as was taken place in the Southern Finland, would have occurred in the reindeer-herding areas in the Finnish Lapland.  相似文献   
72.
The evaluation of vulnerability of process equipment to explosion is a central issue in the analysis of industrial risks. In this work, we have developed a simplified model, however based on fundamental equations, which includes structural and fluid–dynamic parameters for the target (the industrial equipment) and for the impacting pressure wave (shock waves) or object (fragment, debris) produced by different type of chemical explosions.The validity of methodology has been assessed by case histories. Several insights on the dynamic of structural interaction of the explosion with the target have been obtained, with specific reference to escalation effects.The model derives from the well-known Johnson's number, often adopted in impact engineering.  相似文献   
73.
Ammonium nitrogen and total germanium are among the main pollutants in the wastewater discharged from the leather industry. The intake of high concentrations of ammonium nitrogen and/or total germanium harms human health and biological species, as is well documented in literature. This paper focuses on assessing the trends of ammonium nitrogen and total germanium concentrations through time in two watersheds (Aojiang and Oujiang) in the Wenzhou metropolitan area of Zhejiang Province and their relationships with the released wastewater using regression and correlation statistics. The paper also utilizes the integrated pollution index to evaluate water quality in the two watersheds. Preliminary results show that, from 1992 to 1998 in the Aojing watershed, the concentrations of ammonium nitrogen and total germanium increased 13 and 14 times, respectively, decreasing somewhat after 1998, while between 1992 and 1997 in the Oujiang watershed, the concentrations increased, then decreased after 1997. The concentrations of ammonium nitrogen and total germanium are positively related to the amount of released wastewater. The concentrations of ammonium nitrogen and total germanium exceeded water standards 12 and 3 times, respectively, in Pingyang county of the Aojiang watershed, 14 and 3.3 times in Lucheng District of the Oujiang watershed, and 14 and 3.8 times in the Ouhai Oujiang watershed, respectively. In Pingyang county of the Aojiang watershed, the water quality degraded from Type III in 1992 to over Type V in 2003, and in the Oujiang watershed, the water quality degraded from Type II to over Type IV in 1999, when they were compared with the water quality standards. The water quality slightly improved in 2003 for the Oujiang watershed. It appears that pollution did have a direct positive correlation with leather industry production in the Pingyang Aojing watershed, while there was a negative correlation between the two in the Oujiang watershed. In these two watersheds, the integrated pollution index did not appear to relate to population dynamics and agricultural production. This paper also discusses the current new methodologies and approaches adopted nationally and internationally to reduce the contaminants and purify the environment for maintaining a sustainable and healthier environment in Wenzhou.  相似文献   
74.
战略环境评价在中国的发展及方法学探讨   总被引:20,自引:0,他引:20  
本文在回顾和评述战略评价(SEA)的发展状况的基础上,从概念和实践的角度,对SEA方法学作了初步探讨,并提出SEA方法学研究的一般思路。  相似文献   
75.
翟由涛  刘莉 《环境科技》2003,16(4):37-38
对燃煤电厂的环评工作中,项目选址、总平面布置、污染防治与清洁生产:冷却塔噪声等一些值得注意的问题进行了探讨,并提出了一些初步意见。  相似文献   
76.
Concentrations of uranium-238 and thorium-232 in soil, water, grass, moss and oil-palm fruit samples collected from an area of high background radiation were determined using neutron activation analysis (NAA). U-238 concentration in soil ranged from 4.9 mg kg(-1) (58.8 Bq kg(-1)) to 40.4 mg kg(-1) (484.8 Bq kg(-1)), Th-232 concentration ranged from 14.9 mg kg(-1) (59.6 Bq kg(-1)) to 301.0 mg kg(-1) (1204 Bq kg(-1)). The concentration of U-238 in grass samples ranged from below the detection limit to 0.076 mg kg(-1) (912 mBq kg(-1)), and Th-232 ranged from 0.008 mg kg(-1) (32 mBq kg(-1)) to 0.343 mg kg(-1) (1.372 Bq kg(-1)). U-238 content in water samples ranged from 0.33 mg kg(-1) (4.0 Bq L(-1)) to 1.40 mg kg(-1) (16.8 Bq L(-1)), and Th-232 ranged from 0.19 mg kg(-1) (0.76 Bq L(-1)) to 0.66 mg kg(-1) (2.64 Bq L(-1)). It can be said that the concentrations of environmental U-238 and Th-232 in grass and water samples in the study area are insignificant. Mosses were found to be possible bio-radiological indicators due to their high absorption of the heavy radioelements from the environment.  相似文献   
77.
INTRODUCTION: The purpose of this study was to examine the impact of a nationwide response to emerging airbag-related deaths among children. This response, implemented in 1996, focused on moving children to a rear seat and increasing proper restraint usage. METHOD: Fatality trends from 1992 through 1996 and from 1996 through 2003 were examined for younger children (ages 0-3) and for older children (ages 4-12). RESULTS: Prior to 1997, a steady reduction in unrestrained deaths (among younger children) was offset by increases in restrained deaths (among younger and older children), increases in rear-seat deaths (among younger children), and increases in front-seat deaths (among older children). After 1996, there were significant decreases in fatalities in both age groups, with larger and more immediate reductions among the younger children. The largest reductions were immediately after 1996, when younger-child deaths declined by 16%, and after 1999, when deaths among both age groups declined by about 16%. CONCLUSIONS: The immediate reduction in front-seat deaths among younger children, particularly infants, appears to have been closely associated with the nationwide public information efforts implemented in 1996. Later reductions in front-seat and unrestrained deaths, among both younger and older children, were likely associated with the combination of legislative, enforcement, and public information programs, which increased after 1999. IMPACT ON INDUSTRY: The findings suggest that a large expenditure of resources by public and private-sector organizations after 1996 resulted in the prevention of hundreds of deaths among young children. In addition, the results provide insights with regard to the categories of deaths most affected by such programs and issues that deserve additional attention.  相似文献   
78.
The present paper aims at investigating how changes in canopy structure and species physiology associated with the abandonment of mountain meadows and pastures affect their net photosynthesis. For this purpose, a multi-layer vegetation–atmosphere transfer (VAT) model is employed, which explicitly takes into account the structural and functional properties of the various canopy components and species. Three sites differing in land use are investigated, a meadow, a pasture and an abandoned area. Model simulations agree reasonably with measured canopy net photosynthetic rates, the meadow featuring the highest daily net photosynthesis, followed by the pasture and, finally, the abandoned area. A detailed process analysis suggests this ranking to be mainly due to bulk canopy physiology, which decreases from the meadow to the pasture and the abandoned area, reflecting species composition and species-specific photosynthetic capacities. Differences between the canopies with regard to canopy structure are found to be of minor importance. The amounts of green, photosynthetically active plant matter are too similar at the three sites to be a major source of variation in net photosynthesis. Large differences exist between the canopies with regard to the amount of photosynthetically inactive phytoelements. Even though a model analysis showed them to be potentially important, most of them are accumulated close to the ground surface, where they exert little influence on canopy net photosynthesis.  相似文献   
79.
广州李坑垃圾填埋场水环境污染调查   总被引:7,自引:1,他引:7  
通过现场采样与历史资料统计,分析了广州市李坑垃圾填埋场垃圾渗滤液的水质特征,及其对地睛水和地表水的影响强度及范围,结果表明,该场对环境产生影响的主要污染物是以NH3-N、CODCr为代表的高浓度有机物、垃圾渗滤液对地下水的影响强度不大,对作为农业灌溉用水的地表水影响不超过2000m,对10km上的饮用水源不造成影响  相似文献   
80.
为了解决微波对人脑的辐射问题,提出一种新型的手机微波防护器,经实验测得采用了微波防护器人脑侧微波辐射功率密度一律可降至5μW/cm^2以下,完全符合国家的卫生标准。有效地解决了手机微波对人脑的辐射问题。适用于各种手机,以及发射台站、雷达台站等微波防护。  相似文献   
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