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141.
介绍了用Wh聚四氟乙烯膜作为渗透材料制作有机物渗透管的方法,并且针对所研制的渗透管的特性、影响渗透率的主要因素及渗透率的稳定性等方面进行了探讨.  相似文献   
142.
PROBLEM: Falls are a leading cause of mortality and morbidity among adults age 65 and older. Population models predict steep increases in the 65 and older population bands in the next 10-15 years and in turn, public health is bracing for increased fall rates and the strain they place on health care systems and society. To assess progress in fall prevention, the Centers for Disease Control and Prevention conducted a research portfolio review to examine the quality, relevance, outcomes and successes of the CDC fall prevention program and its impact on public health. METHODS: A peer review panel was charged with reviewing 20 years of funded research and conducting a SWOT (strengths, weaknesses, opportunities, and threats) analysis for extramural and intramural research activities. Information was collected from grantees (via a survey instrument), staff were interviewed, and progress reports and products were reviewed and analyzed. RESULTS: CDC has invested over $24,900,000 in fall-related research and programs over 20 years. The portfolio has had positive impacts on research, policies and programs, increasing the public health injury prevention workforce, and delivering effective fall prevention programs. DISCUSSION: Public health agencies, practitioners, and policy makers recognize that while there are some evidence-based older adult fall prevention interventions available, many remain unused or are infeasible to implement. Specific recommendations across the public health model, include: additional research in gathering robust epidemiologic data on trends and patterns of fall-related injuries at all levels; researching risk factors by setting or sub-population; developing and testing innovative interventions; and engaging in translation and dissemination research on best practices to increase uptake and adoption of fall prevention strategies. CDC has responded to a number of suggestions from the portfolio review including: funding translation research of a proven Tai Chi fall intervention; beginning to address gaps in gender, ethnic, and racial differences in falls; and collaborating with partner organizations who share in CDC's mission to improve public health by preventing falls and reducing fall-related injuries. IMPACT ON INDUSTRY: Industry has an opportunity to develop more accessible and usable devices to reduce injury from falls (for example, hip protectors and force reducing flooring). By implementing effective, evidence-based interventions to prevent falls and reduce injuries from falls, significant decreases in health care costs can be expected.  相似文献   
143.
宜昌市城区灰霾天气成因分析研究   总被引:5,自引:1,他引:4  
从灰霾天气形成的可能影响因素出发,根据长期的气象和环保观测资料,将近10年来宜昌市城区逆温层与等温层、降水日、风速风向、环境空气质量优良天数、可吸入性颗粒物(PM10)年均值、二氧化硫(SO2)年均值、二氧化氮(NO2)年均值的观测值与灰霾日观测值进行相关分析,并分析了宜昌市城区环境污染的气象化学作用,揭示出宜昌市城区灰霾天气成因主要是与不利扩散和降解的气象化学作用有关,与目前环境空气质量监测的PM10、SO2、NO2三个指标无明显相关关系,而与细粒子、气溶胶污染有关。  相似文献   
144.
生态保护工作的发展包括环境保护和污染治理两个方面,为了保证生态环境的健康发展,必须要同时做好这两方面工作。在污染治理过程中土壤修复是重要的治理内容,也是污染治理的重要研究方法。本文主要对污染土壤修复技术研究现状进行分析,并对其未来的发展趋势进行预测。  相似文献   
145.
水污染物浓度控制和排放总量控制是水质达标管理的前提。本文将其和水污染物的总量控制发展进程相互结合,对实施应用和理论完善以及深入探讨等阶段的进展进行阐述,介绍污染物总量控制实施时的总量分配和入河控制等相关技术细节,得到总量控制的实施优点,最后明确控制污染物总量的具体意义。  相似文献   
146.
我国二恶英和多氯联苯的研究现状及对策分析   总被引:1,自引:0,他引:1  
为了解二恶英(PCDD/Fs)和多氯联苯(PCBs)在中国的研究水平、研究能力和驱动力,本文对有关研究论文的数量、题材、内容、资助来源和研究机构进行了系统调查和分析。调查发现,国内相关研究尚处在起步阶段,研究的方向和重点还需要进一步调整,研究能力有限,研究机构间合作交流不充分。针对这些问题,提出了相应的对策建议。  相似文献   
147.
Ten Key Questions About the Management of Water in the Yellow River Basin   总被引:3,自引:0,他引:3  
Water is scarce in many regions of the world, clean water is difficult to find in most developing countries, there are conflicts between irrigation needs and urban demands, and there is wide debate over appropriate means of resolving these problems. Similarly, in China, there is limited understanding of the ways in which people, groups, and institutions contribute to, are affected by, and respond to changes in water quantity and quality. We use the example of the Yellow River basin to argue that these social, managerial, and policy dimensions of the present water problems are significant and overshadow the physical ones. Despite this, they receive relatively little attention in the research agenda, particularly of the lead agencies in the management of the Yellow River basin. To this end, we ask ten research questions needed to address the policy needs of water management in the basin, split into two groups of five. The first five relate to the importance of water in this basin and the changes that have affected water problems and will continue to do so. The second five questions represent an attempt to explore possible solutions to these problems.  相似文献   
148.
Graduate researchers are an essential part of higher education (HE) in terms of its contribution to knowledge and the wider economy, but how the work environment influences behaviour and productivity in this work domain is poorly understood. Nevertheless, building programmes continue with a detectable trend towards more open office designs. Beyond issues of cost-efficiency, this reflects a popular belief in the significance of face-to-face interaction to research productivity. Using a combination of subjective and quantitative methods, this case study investigates the validity of this claim and how a redesigned environment impacts upon work practices and collaboration within a community of researchers. Although the new environment was judged favourably by occupants and managers, analysis suggests a less positive behavioural response. Contrary to expectation, we conclude that providing open plan environments is not sufficient to produce more collaborative practices in HE. We argue that this would require changes in the organisational structure, the reward structure for individual and team-driven tasks, and the firm policing of the management of change.  相似文献   
149.
道路交通噪声自动监测中最少监测时间研究   总被引:1,自引:1,他引:0       下载免费PDF全文
以城市主干线为例,对长期道路交通噪声自动监测数据进行统计分析,得出道路交通噪声实施噪声自动监测时应采用的小时最少监测时间、日昼夜最少监测小时、季最少监测天数和年最少监测天数。  相似文献   
150.
目的研究破解高寒地区雷达装备保障问题的对策。方法采取查阅文献、实地查看、实装操作等方法分析研究高寒地区环境对雷达装备保障的影响。结果从打牢基础、精心保障;未雨绸缪、超前保障;紧贴实战、专项保障;机关指导,高效保障四方面,提出了破解高寒地区雷达装备保障问题的对策。结论高寒地区环境因素影响降低了雷达装备环境适应性,降低了其原有的作战效能。研究分析结果将对预防高寒地区雷达装备故障、延长装备服役年限,提高装备保障水平和作战能力,有着重要的现实意义。  相似文献   
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