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31.
Footprints for Sustainability: The Next Steps   总被引:21,自引:0,他引:21  
The concept of an ecological footprint is based on the understanding that every individual human appropriates a share of the productive and assimilative capacity of the biosphere. An ecological footprint corresponds to this exclusive biologically productive area that a defined population uses for all its resource requirements and wastes, and is expressed in terms of bioproductive space, with world-average productivity. Humanity's footprint or its aggregate ecological demand can only temporarily exceed the productive and assimilative capacity of the biosphere without liquidating and weakening the natural capital on which humanity depends fundamentally. Therefore, accounting tools for quantifying humanity's use of nature are essential for overall assessments of human impact as well as for planning specific steps towards a sustainable future.This paper discusses the strengths and weaknesses of the ecological footprint as an ecological accounting method, points out research needs for improvement of the analysis, and suggests potential new applications. The paper identifies ten new applications of the tool to make it applicable at various geographic scales and for a number of analytical and didactic purposes. Then nine methodological improvements are suggested that could refine the currently applied method, making assessments more sensitive to a larger number of ecological impacts. It concludes that many crucial questions pertinent to building a sustainable society can be addressed by current ecological footprint research. By making the method more complete, this tool could evolve from being largely of pedagogical use to become a strategic tool for policy analysis.  相似文献   
32.
分析了导布辊辊筒加工中的一个重要工艺辘圆工艺。论述了完成这个工艺的装备 ,辘头、辘模和辘床的一些设计方法  相似文献   
33.
Earthen embankment dams comprise 85% of all major operational dams in the United States. Assessment of peak flow rates for these earthen dams and the impacts on dam failure are of high interest to engineers and planners. Regression analysis is a frequently used risk assessment approach for earthen dams. In this paper, we present a decision support tool for assessing the applicability of nine regression equations commonly used by practitioners. Using data from 108 case studies, six parameters were observed to be significant factors predicting for peak flow as a metric for risk analysis. We present our work on an expanded earthen dam break database that relates the regression equations and underlying data. A web application, regression selection tool, is also presented to assess the appropriateness of a given model for a given test point. This graphical display allows users to visualize how their data point compares with the data used for the regression equation. These contributions improve estimates and better inform decision makers regarding operational and safety decisions.  相似文献   
34.
RaMCo is a prototype version of a decision-support system for coastal-zone management. The model is based on the findings of a multidisiciplinary research program, conducted in Southwest Sulawesi, Indonesia. Different management strategies can be compared on the basis of the short- and long-term consequences. Land-use change has been included in RaMCo in view of the impacts of land-based human activities on the marine environment. The key aspect of the model is a combination of the temporal dynamics of land-use change on the regional (macro-level) scale and spatial dynamics on the local (micro-level) scale. Constrained cellular automata are used to integrate both scale levels. The state changes of the cells depend on the consistency with the macro-scale model, local geographical conditions, and interaction with neighboring cells. In this paper, we discuss the underlying theoretical assumptions of the macro-scale and micro-scale models, some characteristic results for land-use change in the study area, and the validation problem.  相似文献   
35.
Environmental and health problems associated with the use of digested sewage sludge hinder its application and encourage the introduction of additional treatments such as composting and thermal drying. The aim of this paper is to assess the possibility of using three different types of sewage sludge (digested, composted and thermally dried) to improve soil fertility and enhance the transformation of an unproductive shrub land into a Mediterranean dehesa for grazing purposes and also to reduce wildfire risk. In total, 10t ha(-1) of dry matter of three types of sewage sludge were spread on the soil surface of 4x5m field plots, and then seeded with a mixture of grasses. Effects on soil fertility and plant growth were monitored over 2 years. The results show that all three types of sludge application had a significant effect on vegetation cover, herbaceous biomass (2767.7+/-716.1 and 1735.0+/-299.7kgha(-1) for digested sludge amended and control plots, respectively) and tree growth (0.41+/-0.108cmyear(-1) on amended trees, 14.6% more than control trees). This study proposes the use of multi-criteria analysis to identify the most suitable fertilization alternatives and to assist in the decision-making process of sludge recycling. Because of the high degree of uncertainty and conflicting objectives associated with these decisions, multi-criteria evaluation tools make a valuable contribution to decision-making processes concerning sewage sludge applications. According to multi-criteria results, the composted sludge alternative is the most suitable. This is because all the objectives are achieved: an improvement in the properties and functions of the soil with a positive vegetation response as well as minimal economic cost and risk of toxicity.  相似文献   
36.
The recently-adopted global Sustainable Development Goals (SDGs) will have significant implications for national development planning in both developed and developing countries in the post-2015 period to 2030. Integrated, nationally-owned SDG strategies will be at the centre of national efforts to implement the new sustainable development agenda. The long-run processes and systems perspective that are inherent in the SDGs present complex analytical problems for policymakers and analysts. Scenario analysis and quantitative modelling will be important analytical tools to support national sustainable development planning, and there is an increasingly sophisticated suite of models available to decision makers. This paper reviews and assesses a broad range of different quantitative models that have the potential to support national development planning for the SDGs. The study develops a typology and inventory of 80 different models, and then reviews the comparative strengths, weaknesses and general utility of different models through an initial screening and subsequent multi-criteria analysis of short-listed models. Current gaps in model capabilities are highlighted in the context of providing analytical support for national development planning for the SDGs. While some existing models are particularly relevant, it is unlikely that an ideal model can analyse all SDG targets and variables of interest within a single modelling framework. Top-down ‘macro framework’ models are likely to be more useful for undertaking system-level or economy-wide scenario analysis driven by the national long-term goals and targets, and for exploring trade-offs and synergies among sectors. Bottom-up sectoral models will be able to support far more detailed option-level impact analysis of concrete interventions, technologies and investments. Combining both approaches within an analytical framework will provide a robust approach for analysis and decision-making. The results highlight a range of potential gaps in current modelling capabilities, and provide some new tools to assist with model selection.  相似文献   
37.
高压水射流清洗设备和器材的主要零件,由于经常接触水和空气而产生锈蚀,这是一个比较普遍、简单而又是“老大难”的课题。主要零件的锈蚀,不仅降低其使用寿命,增加维修费用,还提高了操作成本,并且影响设备和器材的使用效率。结合工作实际,通过对常用防锈材料和工艺的分析,并与化学镀镍磷进行比较、试验以及工业化应用,指出了采用化学镀镍磷技术对主要零件进行处理,能改善其化学和物理性能,这是目前解决高压水射流清洗机具防锈蚀的好方法之一  相似文献   
38.
ABSTRACT: Mathematical modeling techniques are used to develop predictive equations for cost of water and waste water treatment processes in developing countries utilizing socioeconomic, environmental, and technological indicators. Predictive equations are developed for each of the three regions (Africa, Asia, and Latin America) for construction, operation, and maintenance costs of slow sand filter, rapid sand filter, stabilization lagoon, aerated lagoon, activated sludge, and trickling filter. Data analysis indicated that cost of water treatment processes is a function of technological indicator (percentage of imported materials), population, and the design capacity. The variables which gave the best correlation for waste water treatment cost were population, design flow, and the percentage of imported waste water disposal materials.  相似文献   
39.
生物多样性保护法律的有效执行,应立足于具体规制工具的设计。生物多样性保护立法涉及三个主要法律领域——物种保育法、自然保护地法和生物安全法,从法律规范层面分析,这三个法律领域对规制工具的偏好与选择呈现出"硬者极硬,刑罚优先,软者无力"的整体格局。本文以生物多样性保护原理对现行规制工具进行检验,物种保育法和自然保护地法应以规制领域的去极端化为导向进行规制工具更新,一方面要软化甚至去除极硬规制,与此同时应建立完善行政合同、行政指导、行政奖励等柔性规制工具,赋予其可操作性,使之柔而有力。  相似文献   
40.
Purpose. In lower-middle-income countries, most of the work is performed manually using non-ergonomic hand tools which results in work-related health problems. Using hand tools designed in line with ergonomic principles may play an important role in reducing work-related health concerns significantly. Methods. Scientific databases (PubMed, EBSCOhost) and e-publishers were searched for articles from 1985 to 2015 using the following keywords: ‘hand tool’, ‘ergonomics’, ‘usability’ and ‘design’. After applying selection criteria to 614 articles, 58 articles related to the physical design of hand tools were selected. Results. Seventeen articles were related to hand tool improvement in the manufacturing sector. Musculoskeletal disorders were found to be the most frequently occurring work-related health problems. Most of the articles focused on product and qualitative variables for improvement in hand tools, while few articles considered human and task variables. Conclusions. Literature shows that hand tool improvement studies have been given less importance in low-income and lower-middle-income countries. However, some work of significance is reported in the agriculture sectors of these countries. Hence, it is concluded that ergonomic intervention in hand tools is much needed for those industries which employ traditional methods of working.  相似文献   
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