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331.
The numerous formulated products which are introduced to the market consist of chemical ingredients that may cause various safety and health hazards to the consumers. Therefore, it is extremely important to practice a systematic methodology to formulate products with acceptable safety and health performances. This work presents an index-based methodology to assess the safety and health hazards of the ingredients during the early formulation stage of product design. Hence, new inherent safety and health sub-indexes are introduced to improve the current safety and health hazards that are needed in formulated product design. The inherent safety and health sub-indexes are assigned with scores based on the degree of potential hazards. A higher score indicates a higher safety risk or severe health effect, and vice versa. The proposed methodology will greatly assist the users to identify the adverse safety and health effects caused by the ingredients. Hence, it is pivotal to eliminate or reduce the safety and health impacts from product usage. A case study on common ingredients used in the formulation of paint is presented on this study to describe the proposed method.  相似文献   
332.
本文试图从区域、自然资源本身和资源的外部条件出发,通过分析区域优势自然资源的概念,选择建立了衡量区域优势自然资源的6项标准体系,并以河南省黄河两岸地区为例,借助与高层次区域的比较研究,确定了该区域的优势自然资源是:铝土矿为第一优势资源,天然气为第二优势资源,以下资源次序为石油、煤、金矿、水泥灰岩、耐火粘土和水资源等。这为合理开发区域优势自然资源提供了重要科学依据.  相似文献   
333.
ABSTRACT: The statistical analysis of data which have trace level measurements has traditionally been a two-step process in which data are first censored using criteria based on measurement precision, and then analyzed with statistical methods for censored data. The process might be more informative if data were left uncensored. In this paper, information loss attributable to censoring and measurement noise are assessed by comparing the sample mean and median of uncensored measurements with a log regression mean and median based on censored data. Measurements are derived from lognormal parent distributions which have random variability characteristic of trace level measurement. The relative performance of estimators used with error-free samples and with samples having measurement noise can be explained by differences between the probability distributions of parents and measurements. Measurement introduces bias and dispersion and transforms lognormal parent distributions toward greater symmetry. Estimates using uncensored data are less biased and more accurate than the log regression mean and median when censoring exceeds about 50 percent, and are not much worse at any fraction censored. For data with many (80 percent) results below the limit of detection, bias may be quite severe.  相似文献   
334.
ABSTRACT: The snowmelt-runoff model (SRM) was used to produce accurate simulations of streamfiow during the snowmelt period (April-September) for ten years on the Rio Grande Basin (3419 km2) near Del Norte, Colorado, U.S.A. In order to use SRM in the forecast situation, it was necessary to develop a family of snow cover depletion curves for each elevation zone based on accumulated snow water equivalent on April 1. Selection of an appropriate curve for a particular year from snow course measurements allows input of the daily snow cover extent to SRM for forecast purposes. Data from three years (1980, 1981, and 1985) were used as a quasi-forecast test of the procedure. In these years forecasted snow cover extent data were input to SRM, but observed temperature and precipitation data were used. The resulting six-month hydrographs were very similar to the hydrographs in the ten simulation years previously tested based on comparisons of performance evaluation criteria. Based on this result, the Soil Conservation Service (SCS) requested SRM forecasts for 1987 on the Rio Grande. Using the same procedure but with SCS estimated temperature and precipi-tation data, SRM produced a forecast hydrograph that had a r2= 0.82 and difference in seasonal volume of 4.4 percent. To approximate actual operational conditions, SRM computed daily flows were updated every seven days with measured flows. The resulting forecast hydrograph had a R2= 0.90 and a difference in volume of 3.5 percent. The method developed needs to be refined and tested on additional years and basins, but the approach appears to be applicable to operational runoff forecasting using remote sensing data.  相似文献   
335.
棉纺车间噪声综合治理   总被引:3,自引:0,他引:3  
邹定  徐桦 《环境工程》2000,18(6):43-44
介绍长达 95m的棉纺车间各噪声点的噪声起源及控制方法  相似文献   
336.
近年来由于地下水补给区的盲目开发和市区地下水超采,素以“泉城”闻名的济南市泉水持续断流,加强泉域地下水补给区的生态环境保护是解决这一问题的关键,在详细研究区域地质水文条件的基础上借助地理信息系统,将补给区划分为三级保护区,即核心保护区,直接补给区和间接补给区,并应用环境承载力分析的理论方法,确定出保护区23个汇水区的环境承载人口,本文对泉域地下水补给区总体发展战略和具体保护规划的制定具有重要的意义。  相似文献   
337.
青海省格尔木地区地下水位六年来平均上升了6.203m,造成了国内外罕见的严重灾害。本文以实际资料为依据,用水均衡方法研究地下水位上升机理。以水库蓄水为界限,划分两个均衡期,分别建立方程并求出使地下水位上升的储存量的增加量为4.84m~3/s。分解后得水库岸边渗漏量及水库调蓄、控水引发的河水渗漏量为10.51m~3/s,其储存量的增加量是4.31m~3/s,占总量的88.8%。  相似文献   
338.
卤虫对毒物毒性监测方法研究   总被引:10,自引:0,他引:10  
以孵化好的 - 期卤虫为受试生物 ,实验研究了 As2 O3、Hg Cl2 、KCN、K2 Cr2 O7、苯、苯酚、六六六7种物质对卤虫的中毒阀值和 L C50 - 2 4h(L eathal、Concentration 5 0 - 2 4hours,2 4小时半致死浓度 )的测定 ,该方法具有操作简便、快速、覆盖面宽、技术易掌握、所需设备不复杂等特点。  相似文献   
339.
两个相邻高建筑物周围的风环境   总被引:3,自引:0,他引:3  
海颖  宣捷 《环境工程》1999,17(2):52-55
描述研究了建筑物周围人行道高度风速分布特征的风洞模拟实验。结果表明:在一个横风向宽度很大的高大建筑物的迎风面拐角附近,风速增大约1倍;而在建筑物的前方有风速的骤变区,这均形成严重的风环境问题。当用一通道将该建筑物分割成两个相邻建筑物时,上述两方面的风环境问题得到了有效的改善,且通道宽度与建筑物顺风向尺度之比的优化数值在18至24之间  相似文献   
340.
本文通过对三门峡水利枢纽工程外部地震形变监测成果的分析,阐述了大坝地震形变监测的基本内容,简述了三门峡水利枢纽及其与库区水位相关的变化规律,提出了解决水利枢纽地震安全监测中剔除库水位干扰的通用方法。  相似文献   
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