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21.
White-fronted bee-eaters live in patrilocal, extended family groups in which several pairs may breed simultaneously and in which helping behavior by nonbreeders is common. The composition of a male's family, and his social position within it, are major predictors of his expected reproductive success. For females, the dispersing sex, a decision to pair necessitates forfeiting any potential fitness benefits available through helping in her family, in favor of the potential benefits of breeding in the male's family. Using a set of equations that incorporate the social and non-social predictors of nesting success, we develop a payoff matrix for the expected fitness (current and future) of pairing with different categories of males. Predictions generated from this payoff matrix were supported by data: (1) Females that could help close kin (and thus garner large indirect benefits) tended to remain unpaired. (2) Males with social characteristics associated with low expected reproductive success were more often rejected as potential mates by females. (3) High-quality males, those with potential helpers of their own, were nearly always paired. Simulation analyses were used to investigate female pairing decisions in more detail, and to test various hypotheses about possible decision rules. We demonstrate that pairing females incorporate an assessment of the family structure of potential partners into their mate choice decisions. Such social characters represent an aspect of female choice that has been underappreciated. We suggest that social characters will prove to be important components of mate choice decisions in many species where kinship and dominance considerations influence the likelihood, or success, of breeding.  相似文献   
22.
While regulations have advanced product take-back in some markets, challenges to increasing product reuse and remanufacturing remain. Most research to date has focused on original equipment manufacturers taking back and remanufacturing their products, which is often problematic. The present study demonstrates that there are emerging opportunities for small companies with innovative business models to enter the market and advance product end-of-life (EoL) management. The paper examines the biotechnology industry – a growing sector with high spending on lab equipment and relatively short lifespans of research and development instruments. Building on previous research and analysis of industry practices and emerging drivers for product reuse and remanufacturing, the authors propose a framework for sustainable EoL management that includes five managerial drivers: financial benefits, space, ease/convenience, information, and sustainability goals. The paper concludes with discussion of the lessons learned and practical implications for managers in charge of purchasing or disposing of surplus equipment.  相似文献   
23.
The aim of this research was to define a sequence of actions to guide redesign propositions for electrical and electronic equipment products, which minimise negative consequences to the environment after the end of their useful life. Current practices mainly encourage the examination of individual problems as disassembly process and identification of suitable product end-of-life (EOL) treatment strategies. There also exist previous studies that try to incorporate EOL concerns in product design phase. In most cases, the main problem is the limited available EOL information because of its delayed retrieval. The proposed method focuses primarily on minimising this problem. The steps of the analysis performed include the selection of the optimal EOL treatment strategy and, afterwards, the evaluation of its results concerning the environment. In parallel, product design characteristics are grouped and examined concerning their expected significance for the environment in the EOL stage. The results from the previous stages are combined and product improvement actions are proposed for further examination in the redesign stage. The general framework used to conduct all these actions is lean thinking methodology. In the end, results concerning the application of the proposed method on a distribution transformer are presented.  相似文献   
24.
Background, Aims and Scope When joining the European Union on 1st May 2004, Estonia had to conform its legislation to the European Union legislation. In relation with that, also the treatment requirements on end-of-life vehicles proceeding from Directive 2000/53/EC of the European Parliament and of the Council of 18 September 2000 were established in Estonia for the first time. Since this area was not regulated with law beforehand, there was not any information available about it. The aim of the current survey was to ascertain the condition of scrap yards in mid 2004. In addition to that, also to identify the number of scrap yards operating in Estonia, to classify these by the number of dismantled vehicles and the potential environmental hazard, and to map the locations of car dismantling companies and evaluate their compliance with the valid requirements. Methods The companies that have been registered in the Commercial Registry under the activity code 503090-end-of-life vehicle dismantling were visited and visually reviewed. During the visits, the compliance of scrap yards with the existing requirements was evaluated and it was also attempted to identify how environmentally sound the dismantling technology of every scrap yard owner is. Results and Discussion Altogether, 63 scrap yards operated in Estonia by mid 2004. Twelve of them dismantled more than 100 vehicles, 13 of them 51-99 vehicles and 38 up to 50 vehicles a year. The total annual market capacity on dismantling of vehicles in Estonia is considered to be approx. 10,000 units. There are very few companies dealing only with car dismantling as the main business. Most scrap-yard owners also offer side services, e.g. haulage, car repair and maintenance. The dismantlers are interested in the selling of second-hand spare parts and scrap metal. Only one company out of 63 complied with all the requirements enacted by the relevant decision of the Estonian Minister of Environment. The rest of the scrap yards did not meet the requirements on the site on storage and treatment nor did they have the hazardous waste handling licence or the waste permit. Of the requirements established for the site for storage of end-of-life vehicles, 97% of the scrap yards were surrounded with a fence, 67% had a 24-hour guard, 45% had covered the areas with waterproof cover, but only 3% had an oil trap. Sites for treatment were in a somewhat better condition, these were mostly situated inside the buildings, where floors were covered with waterproof covers. Most of the dismantlers collected the waste oil and waste fluids into separate vessels, but there were a number of dismantlers who did not know of existence of polychlorinated biphenyls (PCB) in car air conditioning systems and the availability of mercury in sensors belonging in passenger safety systems. Proceeding from the general condition of the scrap yard, the rest of 62 scarp yards were distributed between two empirical parameters - 'rather environmentally hazardous' or 'rather not environmentally hazardous'. As a matter of fact, 17% of scrap yards turned out 'rather environmentally hazardous'. Conclusion Out of the scrap yards operating in Estonia, only one is compliant with the requirements set up by Directive 2000/53/EC. Another 62 appeared during the review to be sites of potential environmental pollution. In order to comply with environmental requirements and get the hazardous waste treatment license, the scrap yard owners have to invest into state-of-the-art dismantling and environment protection equipment. The main obstacle to reach the environmentally sound scrap-yard is the high investment cost and the black market for spare parts. Recommendation and Outlook As the correction of the market in end-of-life vehicle treatment started after the adoption of Directive 2000/53/EC, the environmental authorities have to look after the ongoing correction. It is because there is still a demand for cheap spare parts and it makes it attractive to dismantle the vehicles out of scrap-yards by licensees.  相似文献   
25.
The current study considered, for the first time, compensatory decisions within the theory of planned behaviour (TPB) to explain why people use mobile phones while driving. The effects of age, gender, and mobile phone mode on respondents’ answering intentions and compensatory decisions were mainly examined. A series of questions were administered to 333 drivers (ages 25-59), which included (1) demographic measures, (2) scales that measured prior mobile use activities in both driving and ordinary contexts, (3) a question to measure drivers’ perceptions of the safety of hands-free phones, and (4) TPB measures, which measured answer intention and two compensatory behavioural decisions (i.e., reminding the caller that he/she is driving, limiting the length of a conversations (including perceived its limits)), along with predictive variables. Drivers reported a moderate likelihood of answering intention and a strong tendency to engage in the two compensatory behaviours. Answering intention and compensatory decisions, perceived behavioural control, perceived risk, and usage frequency were more dependent on mobile phone mode and age group than gender. The regression models explained 64% and 67% of the variance in answering intention in the handheld and hands-free scenario separately. Attitudes, subjective norms, perceived behavioural risk and control (PBRC), and prior answering behaviour emerged as common predictors. The predictive models explained 31% and 37% of the variance for perceived limits of a conversation length in handheld and hands-free scenarios, respectively. Answering intention and PBRC consistently predicted most of the variance (handheld: 28%; hands-free: 32%) for this compensatory perception limits. The theoretical and practical implications of these results are discussed.  相似文献   
26.
Value functions are devices that allow discrete analyses of environmental impacts to be reconciled to a single quantitative scale of preference. The values obtained can then be weighted and combined into measures of the relative desirability of policy alternatives. However, for this methodology to be valid, the set of impacts used must satisfy a number of conditions; and whether or not these are met depends on how the impacts are selected and characterized. This paper generalizes instances where the conditions may be violated and how they may be resolved, and concludes with a few thoughts on how the methodology might be adapted to the routine of bureaucracy.This work was performed under the auspices of the U.S. Department of Energy by the Lawrence Livermore Laboratory under Contract W-7405-ENG-48.  相似文献   
27.
An evaluation of coastal processes, shoreline erosion, and shore management options for Conference House Park, New York, USA, reveals the problems associated with lack of congruence between jurisdictional boundaries and boundaries required for maintenance of beaches and shorefront park land. Rates of shoreline change are high despite low wave energies because bay beaches contain small amounts of sand. The park is so narrow in places that the shoreline will soon move out of park boundaries. This condition will eliminate natural beach resources, restrict access, and create political and administrative problems. Management strategies include revetment construction, beach nourishment, and acquisition of additional land. Obtaining the maximum length of shorefront to create a park may be less cost effective in maintaining natural beach resources than obtaining a shorter frontage and more compact shape that allows for shoreline movement. The problems of managing eroding shorelines in urban estuaries are acute because space is lacking, the cost of land is high, and the critical nature of shoreline erosion is disguised by low wave energies and lack of daily beach change.  相似文献   
28.
随着汽车保有量的快速上升,我国报废汽车市场规模正在进入快速增长区间。根据发达国家的经验,报废汽车拆解与回收利用是循环经济产业的重要支柱。未来我国报废汽车市场规模的增长以及相关资源回收利用市场的发展,将会产生许多新的市场机会,也会对我国循环经济产业发展产生较大影响。  相似文献   
29.
In this paper we conducted a hypothetical choice experiment in Shanghai, China, to examine whether the China Energy Efficiency Label influences consumers' choices of air conditioners and refrigerators. A latent class approach was applied to observe both heterogeneities among the respondents and product brands. Our results suggested that consumers in Shanghai were well aware of the China Energy Efficiency Label and tended to pay more attention to products with such labels. In addition, air conditioners and refrigerators affixed with a hypothetical label that indicates saving in electricity bills compared with a standard model received significant preferences, which suggested that the more information manufacturers provide, the more their products would be preferred by consumers. Finally, weighted by class probability, the willingness to pay values for more energy efficient refrigerators were higher than those for more energy efficient air conditioners, implying that Shanghai consumers have greater incentive to pay more for appliances they use more frequently.  相似文献   
30.
评估是一种权力。各类"评估"实际上都代表了其主管部门的权力和利益,甚至沦为各部门争夺话语权、攫取部门利益的一道关卡。多种评价"混战",不仅评价内容重复、程序烦琐、浪费人力和资源,同时评价背后代表其主管部门的利益和权力,评价的"混战"也成为各部门维护自身利益、争夺话语权的"混战"。本文在对现有评价制度、实施情况、存在问题的剖析的基础上,基于协同推进生态文明建设的要求,提出横向上协同相关部门、纵向上协同国家和地方、政府和市场、政策规划与项目等重大决策的多评融合实施路径,最后提出了多评融合的四项政策建议。  相似文献   
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