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91.
The Safe Drinking Water Act Amendments of 1996 required U.S. utilities to report on drinking water quality to their customers annually, beginning in fall 1999, on the assumption that such reports would alert them to quality problems and perhaps mobilize pressure for improvement. A random sample of New Jersey customers read alternative versions of a water quality report, in an experiment on reactions to water quality information under U.S. Environmental Protection Agency (USEPA) rules. Experiment design was 2 x 3 + 1: two versions each--one with, one without, a violation of a health standard--of a report that was (1) Qualitative (without water quality numbers, thus not meeting USEPA rules); (2) Basic, with minimal information meeting the rules; or (3) Extended, adding reading aids and utility performance information; plus a control instrument without any hypothetical report. Results of ANOVA suggest the reports will have less effect than hoped or feared. These manipulations were successful: people reading the Qualitative versions were less likely to say that the report gave the amounts of substances found in the water, and those reading Violation versions were more likely to report a violation of a health standard. The main differences in responses to the report involved the judged adequacy of the information, and to a lesser extent responses on a Concern scale (constructed from measures of concern, judged risk, clean-up intentions, distrust of utility information, and doubt that the utility was doing all it could to improve water quality). Overall judgments of water quality and utility performance did not change, either relative to the controls or in before versus after responses. Qualitative reports performed worse than others, confirming the decision to have utilities report actual contaminant levels. Extended reports did only slightly better than the Basic versions on these measures. Many respondents had trouble identifying the presence or absence of substance amounts or violations, despite their seeming obviousness (e.g., in a "bottom line" summary on the front page of each report), suggesting many were not processing this information carefully. However, the pattern of responses for those who accurately identified the presence or absence of substance amounts or violations did not differ substantially from that for the group as a whole. Generic risk beliefs (serious local environmental problems; lack of control over risks to one's health) dominated demographic variables, attitudes toward utility water quality or trustworthiness, and the content and format of water quality reports in influencing concern about drinking water quality. Previous empirical and theoretical evidence for lack of change in public risk attitudes due to one-time or infrequent communications--e.g., role of personal experience, perseverance of prior trust or distrust--seems to be confirmed for annual water quality reports.  相似文献   
92.
水资源是人们赖以生存的必需物质。水资源的短缺已经严重影响经济的增长和人们的日常生活。文章基于温斯特指数平滑法理论,对我国九大流域水资源的使用做出预测模型,可以根据历史数据准确预测九大流域下一年度的用水总量和供水总量。这样,可以为管理部门制定符合实际的水资源调配政策提供依据,并且使九大流域地区的人们更高效地利用有限的水资源。  相似文献   
93.
Characterizing all possible chemical mixtures in drinking water is a potentially overwhelming project, and the task of assessing each mixture's net toxicity even more daunting. We propose that analyzing occurrence information on mixtures in drinking water may help to narrow the priorities and inform the approaches taken by researchers in mixture toxicology. To illustrate the utility of environmental data for refining the mixtures problem, we use a recent compilation of national ground-water-quality data to examine proposed U.S. Environmental Protection Agency (EPA) and Agency for Toxic Substances and Disease Registry (ATSDR) models of noncancer mixture toxicity. We use data on the occurrence of binary and ternary mixtures of arsenic, cadmium, and manganese to parameterize an additive model and compute hazard index scores for each drinking-water source in the data set. We also use partially parameterized interaction models to perform a bounding analysis estimating the interaction potential of several binary and ternary mixtures for which the toxicological literature is limited. From these results, we estimate a relative value of additional toxicological information for each mixture. For example, we find that according to the U.S. EPA's interaction model, the levels of arsenic and cadmium found in U.S. drinking water are unlikely to have synergistic cardiovascular effects, but the same mixture's potential for synergistic neurological effects merits further study. Similar analysis could in future be used to prioritize toxicological studies based on their potential to reduce scientific and regulatory uncertainty. Environmental data may also provide a means to explore the implications of alternative risk models for the toxicity and interaction of complex mixtures.  相似文献   
94.
浙江省高校水上救生现状与发展对策研究   总被引:1,自引:0,他引:1  
采用文献资料法、调查法、数理统计法、比较法以及系统分析法,对浙江省高校水上救生现状及存在的问题进行分析与研究,发现高校水上救生存在着学校重视不够,大学生救生意识淡薄,救生宣传和救生员培养滞后等问题。应进一步完善高校水上救生员培训体制和管理体制,形成规范、有序的游泳池管理体系,减少和避免溺水事故。  相似文献   
95.
论述了水利技术经济复合型人才的知识结构 ,总结分析了国内外高等学校现行的水利技术经济复合型人才培养的课程体系 ,在此基础上提出了适应新世纪要求的水利技术经济复合型人才课程体系的设想。  相似文献   
96.
为回收再利用洗衣机在洗涤过程中所排的废水,设计了洗衣机废水自动回收装置,装置由浊度传感器、液位开关、水用电磁阀、潜水泵、水箱等构成。该装置可自动识别废水污浊程度,从而决定是否回收储存起来。经简易处理的回收废水类似于q-水,可用于马桶及地面的冲洗,这对于水资源的节约利用、绿色住宅建筑设施设计具有一定的参考意义,同时也具有一定的经济效益。  相似文献   
97.
提出一种实用、简单、易算的方法──碘量法,来测定水中溶解氧的含量。  相似文献   
98.
本文阐述了通辽市科尔沁区高氟地下水形成的原因、氟病区分布情况以及防氟改水的方法和措施。  相似文献   
99.
蕉园村为肇庆广府村落之一,其水系特征与广府古村落有共同之处,又有自身特点;通过分析蕉因村水系景观现状,提出恢复、保护其水系的设计方案。  相似文献   
100.
G地区P油层由于闭合高度低,油水分异差,存在大量的油水同层,且该区油水同层与油层的物性、电性相近,使得传统的利用电阻率和孔隙度计算含水饱和度的方法失效;加上工区开发过程中采取多层合试,单层试油且产液性质为油水同出的层位较少,可供选择进行油水同层饱和度建模的样本较少,使得该区油水同层饱和度的准确计算成为储量提交的难点。针对这一问题,提出以少量的密闭取芯井为基础样本,首先应用相渗资料建立起产水率与含水饱和度关系,然后外推到常规取芯井获得含水饱和度的补充样本,进而通过优选孔隙度、电阻率比值等建模参数,构建了适用于研究区油水同层的饱和度计算新模型,通过统计,其平均相对误差仅为3.59%,满足了储量计算的精度要求。  相似文献   
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