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81.
气浮综合改进设施处理高浓度造纸废水 总被引:4,自引:0,他引:4
本文报道了气浮综合改进设施处理高浓度造纸废水的流程和改革,结果表明:改进后的气浮设施COD去除率由60%提高到75%,SS去除率由51%提高到71%,气浮出水河直接回用于造纸的主要过程,处理效果明显优于单纯的气浮处理。而且改进部分投资少,动力消耗少,是处理高浓度造纸废水的简便易行、值得推广的方法。 相似文献
82.
设计了一种铁环型周期磁场摇摆器。对此摇摆器的磁场做了细致测试。结果表明,实验与理论设计很好相符。当螺旋线管电流为133A 时,摇摆器可产生0.055T 的远轴径向磁场强度。该磁场强度能满足低能束自由电子激光的要求。本实验可作为其它摇摆器设计时的参考。 相似文献
83.
胥洪泉 《西南大学学报(社会科学版)》2004,30(6)
敦煌变文<太子成道经>叙述释迦牟尼从其母"右胁出身胎"、"袖中生"出,这与印度古代的种姓等级制度密切相关,是婆罗门教所谓不同种姓的人从梵天不同部位生出的神话之体现,"右胁"出生主要是秦汉以后"尊右卑左"观念的影响;释迦太子出生后"九龙吐水"洗浴其身,"九龙"是佛教输入后中国化的产物;释迦牟尼娶妻时所问"三从",是借用儒家提倡的妇道,来表明印度古代妇女在宗法家族中的卑微地位. 相似文献
84.
Branden B. Johnson 《Risk analysis》2003,23(5):985-998
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
85.
Since the introduction and definition of relationship algebras by James (1957), rolatively little use has been made of this theory in experimental design and analysis problems This may be due to the underlying theory of relationship algebras being previously accessible only in books on mathematical structure theory, e.g. van der Waerden (1950) This paper provides a development of the theory of relationship algebras beginning at an elementray level and including only those parts of mathematical structure theory which are essential to this development. An example of its application in derving an analysis due to alling (1967) is presented. 相似文献
86.
87.
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
88.
基于五大发展理念对《大中型水利水电工程建设征地补偿和移民安置条例》(国务院471号令)移民政策的进步性、局限性、制度合理性和实践合理性进行评价,有助于条例的修订完善及水利水电移民事业健康发展.471号令相对于74号令在各个方面都有了较大的进步,但一些条款已经不能适应发展要求,需在五大发展理念的指导下进行完善:移民管理体制要从"管理"转变为"治理",实现创新发展;要进一步明确项目法人与地方政府的权责,实现协调发展;要将生态文明建设、美丽中国建设的新要求贯彻到移民工作中,实现绿色发展;要消除部门立法、行业保护的影响,实现开放发展;要更多地让利于移民及安置区群众,实现共享发展. 相似文献
89.
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
90.
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
茅勇 《浙江海洋学院学报(人文科学版)》2008,25(4):135-138
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