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271.
272.
针对南京市典型道路的交通噪声控制措施,分别选取低噪声路面、声屏障、隔声窗3种噪声控制措施进行监测,监测显示低噪声路面对整体声级降噪有限,声屏障对于1kHz倍频带以上的中高频隔声相对较好,真空玻璃隔声窗能对低频噪声有显著改善。 相似文献
273.
Collective payments for ecosystem services (PES) programs make payments to groups, conditional on specified aggregate land-management outcomes. Such collective contracting may be well suited to settings with communal land tenure or decision-making. Given that collective contracting does not require costly individual-level information on outcomes, it may also facilitate conditioning on additionality (i.e., conditioning payments upon clearly improved outcomes relative to baseline). Yet collective contracting often suffers from free-riding, which undermines group outcomes and may be exacerbated or ameliorated by PES designs. We study impacts of conditioning on additionality within a number of collective PES designs. We use a framed field-laboratory experiment with participants from a new PES program in Mexico. Because social interactions are critical within collective processes, we assess the impacts from conditioning on additionality given: (1) group participation in contract design, and (2) a group coordination mechanism. Conditioning on above-baseline outcomes raised contributions, particularly among initially lower contributors. Group participation in contract design increased impact, as did the coordination mechanism. 相似文献
274.
陈照和 《中国特种设备安全》2013,(10):4-9
文章以国内典型压力容器用材245R为例,采用GB/T19624~断裂力学评价方法对于《压力容器定期检验规程》表5、表6中的超标非圆形缺陷可接受准则的安全裕度进行评价,评价结果表明其中可接受准则的部分规定不够保守,就此作者给出相关的修改建议。 相似文献
275.
H.A. Kuiper 《Journal of environmental science and health. Part. B》2013,48(3):353-363
Abstract The use of agrochemicals like crop protecting agents, veterinary disinfectants, and wood preservatives may result in (un)intentional exposure of the environment, animals and man. This paper deals with current testing strategies to assess the potential health risks for humans exposed to these chemicals during production or application or via consumption of foods containing pesticide residues. Principles and procedures for safety assessment of pesticide residues in food as developed by WHO/FAO are described. Different types of toxicity studies in mammalian test animal species are discussed and a strategy is outlined in order to characterize the toxicity profile of a compound and the relationship between applied doses and adverse effects. Safety testing of agrochemicals should be carried out in relation to its intended use, and in particular attention will be paid to toxicity testing of residues of pesticides in food. Extrapolation of results from animal studies to humans and the use of safety factors is discussed. Besides the use of animal protocol studies for safety testing of agrochemicals, the potential use of in‐vitro models derived from organs and tissues of animals is discussed. Data on the in‐vitro metabolism of thiabendazole, aldicarb and alachlor are discussed in order to demonstrate that such data may complement or partly substitute whole animal experimentation. Principles and procedures for safety testing of residues of agrochemicals in food as applied during the last three decades, constitute a ‘safety‐first’ approach, providing sufficient safety margins for the consumer of foods which may contain low levels of residues of agrochemicals. 相似文献
276.
J. F. Copplestone 《Journal of environmental science and health. Part. B》2013,48(6):683-688
Abstract The importance of field surveys to provide data on acute pesticide hazards is discussed. The types of questions which small field surveys of pesticide exposure should answer are presented. In addition to protective clothing, the value of distance, time, and personal hygiene in reducing exposure are considered. Finally, the importance of an adequate data base for the development of protocols and guidelines for public protection is discussed. 相似文献
277.
Sara P. Bombaci Cooper M. Farr H. Travis Gallo Anna M. Mangan Lani T. Stinson Monica Kaushik Liba Pejchar 《Conservation biology》2016,30(1):216-225
Scientists are increasingly using Twitter as a tool for communicating science. Twitter can promote scholarly discussion, disseminate research rapidly, and extend and diversify the scope of audiences reached. However, scientists also caution that if Twitter does not accurately convey science due to the inherent brevity of this media, misinformation could cascade quickly through social media. Data on whether Twitter effectively communicates conservation science and the types of user groups receiving these tweets are lacking. To address these knowledge gaps, we examined live tweeting as a means of communicating conservation science at the 2013 International Congress for Conservation Biology (ICCB). We quantified and compared the user groups sending and reading live tweets. We also surveyed presenters to determine their intended audiences, which we compared with the actual audiences reached through live tweeting. We also asked presenters how effectively tweets conveyed their research findings. Twitter reached 14 more professional audience categories relative to those attending and live tweeting at ICCB. However, the groups often reached through live tweeting were not the presenters’ intended audiences. Policy makers and government and non‐governmental organizations were rarely reached (0%, 4%, and 6% of audience, respectively), despite the intent of the presenters. Plenary talks were tweeted about 6.9 times more than all other oral or poster presentations combined. Over half the presenters believed the tweets about their talks were effective. Ineffective tweets were perceived as vague or missing the presenters’ main message. We recommend that presenters who want their science to be communicated accurately and broadly through Twitter should provide Twitter‐friendly summaries that incorporate relevant hashtags and usernames. Our results suggest that Twitter can be used to effectively communicate speakers’ findings to diverse audiences beyond conference walls. 相似文献
278.
Kees van Leeuwen 《Environmental management》1990,14(6):779-792
In a recently published annex to the National Environmental Policy Plan of the Netherlands (1989), attention was paid to ecotoxicological
effects assessment. The proposed procedure was based on the advice of the Health Council of the Netherlands (1989) on risk
assessment of toxic chemicals for ecosystems. The various extrapolation methods described by the Health Council are critically
discussed in this paper. The extrapolation method of Van Straalen and Denneman (1989) is evaluated for eight chemicals and
11 aquatic species. Conclusions are drawn about the quality and quantity of the ecotoxicological data needed for aquatic effects
assessment. For the soil—a compartment that is often at risk—ecotoxicological effects assessment is not possible because suitable
ecotoxicological test methods still have to be developed. 相似文献
279.
The provision of sheltered housing for sale in Scotland has experienced rapid growth since the opening of the first scheme in 1982. Development has been geographically concentrated in a small number of inner city and rural (coastal) areas. The expectation of continued rapid expansion is unlikely if recent trends of slower growth continue. This paper uses evidence from interviews with developers and owners of sheltered and mainstream housing, to examine the possible future contribution of the private market. On the basis of such evidence it raises questions about the relevance of some existing planning policies. 相似文献
280.
本文主要论述了如下基本概念问题: 1、安全的主要经济功能是保障社会经济的增值和有效地减少事故的经济损失。本文试图构造增值函数I(S)和损失函数L(S)来描述其功能。 2、安全经济学的基本任务是研究安全的经济效益和安全的经济利益规律,使其有效地调整和协调安全与经济的关系,指导安全经济决策。 3、本文试提出发展安全经济学应遵循的三个基本原理。 4、为综合揭示安全经济规律,本文还探讨了安全经济的功能函数F(S)、成本函数C(S)、负担函数B(S)和效益函数E(S)。 5、针对实际应用,本文还提出了一种安全投资的评价方法及其优化理论。 相似文献