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991.
光催化氧化法处理石灰法草浆造纸废水   总被引:5,自引:2,他引:3  
采用光催化氧化法处理石灰法草浆造纸废水,考察了ZnO加入量、H2O2加入量、废水pH、光照时间与光照强度对废水COD去除率的影响。在ZnO加入量为3g/L、H2O2加入量为14g/L、pH为10.00的条件下,废水经功率500W的低压汞灯照射8h后,其COD为153.8mg/L,COD总去除率可达90%以上。  相似文献   
992.
太阳能作为一种清洁能源,将其应用在造纸污泥干化中,与传统干化工艺相比具有能耗低、无污染、运行费用低廉、操作简单、运行安全稳定、干化后的污泥仍保留原有的价值等特点。以某造纸污泥的干化为例,介绍了该工艺的工作原理及流程、工艺单元设计等。  相似文献   
993.
ABSTRACT: Two simple interactive techniques are developed and illustrated by means of two different real-life examples in Thailand. The first technique, Evolutionary Sequential Multiobjective Problem Solving (ESEMOPS), is an open-ended algorithm designed for planning problems with discrete alternatives. ESEMOPS helps the decision making group (DMG) develop progressively a preference function over the alternatives. The algorithm follows an evolutionary “breeding” strategy to generate a small set of good alternative solutions. This heuristic search, which does not guarantee that the adopted ‘satisfactum’ is an efficient solution leads to plausible results when applied to the planning of the Mae Khlong-Chao Phraya interbasin water transfer and irrigation system. The second algorithm, Search Beam Method (SBM) is essentially a series of one-dimensional searches for an efficient point along a “beam” passing through a goal point. Repeated search towards displayed goal points is leading to a set of quasi non-dominated solutions. SBM is illustrated by the Ubol Ratana reservoir control problem with the two conflicting objectives of energy generation and irrigation water supply. Neither ESEMOPS nor SBM require that weights, utilities, or pairwise tradeoffs be assessed. These features have been very much appreciated by a real DMG presented with the two techniques.  相似文献   
994.
This article presents the design of a fuzzy decision support system (DSS) for the assessment of alternative strategies proposed for the restoration of Lake Koronia, Greece. Fuzzy estimates for the critical characteristics of the possible strategies, such as feasibility, environmental impact, implementation time, and costs are evaluated and supplied to the fuzzy DSS. Different weighting factors are assigned to the critical characteristics and the proposed strategies are ordered with respect to the system responses. The best strategies are selected and their expected impact on the ecosystem is evaluated with the aid of a fuzzy model of the lake. Sensitivity analysis and simulation results have shown that the proposed fuzzy DSS can serve as a valuable tool for the selection and evaluation of appropriate management actions. Note: This version was published online in June 2005 with the cover date of August 2004.  相似文献   
995.
Connecting Multiple Criteria Decision Support (MCDS) methods with SWOT (Strengths, Weaknesses, Opportunities, and Threats) analysis yields analytical priorities for the factors included in SWOT analysis and makes them commensurable. In addition, decision alternatives can be evaluated with respect to each SWOT factor. In this way, SWOT analysis provides the basic frame within which to perform analyses of decision situations. MCDS methods, in turn, assist in carrying out SWOT more analytically and in elaborating the results of the analyses so that alternative strategic decisions can be prioritized also with respect to the entire SWOT. The A'WOT analysis is an example of such hybrid methods. It makes combined use of the Analytic Hierarchy Process (AHP) and SWOT. In this study, a hybrid method of the Stochastic Multicriteria Acceptability Analysis with Ordinal criteria (SMAA-O) and SWOT is developed as an elaboration of the basic ideas of A'WOT. The method is called S-O-S (SMAA-O in SWOT). SMAA-O enables the handling of ordinal preference information as well as mixed data consisting of both ordinal and cardinal information. Using SMAA-O is enough to just rank decision elements instead of giving them cardinal preference or priority ratios as required by the most commonly used MCDS methods. Using SMAA-O, in addition to analyzing what the recommended action is under certain priorities of the criteria, enables one to analyze what kind of preferences would support each action. The S-O-S approach is illustrated by a case study, where the shareholders of a forest holding owned by a private partnership prepared the SWOT analysis. Six alternative strategies for the management of their forest holding and of old cottage located on the holding were formed. After S-O-S analyses were carried out, one alternative was found to be the most recommendable. However, different importance orders of the SWOT groups would lead to different recommendations, since three of the six alternatives were efficient according to S-O-S analyses.  相似文献   
996.
Chains of accidents, in literature generally referred to as domino effects, knock-on effects, cascade effects or escalation effects occur very infrequently but with disastrous consequences. There exist very few software packages to study such domino accidents in complex industrial areas and to forecast potential catastrophes caused by secondary order (involving a sequence of three installations submitted to two consecutive accidents), tertiary order or even higher order accidents. Moreover, available domino software focuses on risk assessment and on consequence assessment. None of these toolkits specifically addresses the prioritization of installation sequences in an industrial area in order to facilitate objective prevention decisions about domino effects. This paper describes the application of a new computer-automated tool designed to support decision-making on preventive and protective measures to alleviate domino effects in a complex surrounding of chemical installations. Using a holistic approach and thus looking at the entire industrial area as a whole, all sequences of three installations in the area are ranked according to their danger contribution to domino effects. An example of a cluster of chemical plants demonstrates the level of qualitative and quantitative input data required. The example is also used to explain the toolkit results, as well as the surplus value and the benefits for company safety managers and regulators.  相似文献   
997.
Investment in Chemical Process Industries for improving their safety requires considering risk level, environmental effect, cost and many other aspects simultaneously. This paper focuses on a new systematic method of finding the most cost–risk–effective investment scenario set. The method uses the automatic accident scenario generation technique first to find a set of the most dangerous scenarios. Then it uses the multiobjective optimization method to decide the priority of the investment. These computations includes considering many constraints such as limited budget, environmental requirements and social demands. The Styrene Monomer plant case study proves the practical use of this integration method of accident scenario generation and multiobjective optimization.  相似文献   
998.
根据小城镇污水处理方案影响因素具有不完全性和不确定性的特点,建立了小城镇污水处理方案的模糊相似优先比决策模型,在该模型中,定义了模糊相似比,构造了污水处理方案影响因素的模糊相似优先关系,利用层次分析法确定了各影响因素的权重,从整体上找出了与理想方案最为相似的处理方案。实例分析表明,该模型决策结果合理、使用方便具有实用价值,为污水处理方案的决策分析提供参考。  相似文献   
999.
基于决策树的土壤Zn含量预测   总被引:3,自引:0,他引:3  
张秀英  孙棋  王珂  蒋玉根  林芬芳  韩凝 《环境科学》2008,29(12):3508-3512
以浙江省富阳市为研究区域,基于184个土壤表层(0~20 cm)样点的Zn浓度数据(根据背景值划分为G1、G2、G3、G4和G5共5个层次),并结合土壤类型、pH值、有机质、农业用地方式、工矿企业类型、道路和农村居民点等环境因子,采用CART方法挖掘Zn在土壤中的累积规则.利用获得的规则预测剩余41个土壤样点的Zn浓度,并进行精度评价.结果表明,采用CART方法获得的结果比普通Kriging插值方法获得的结果总精度提高了21.95%,在G2和G5层次上模拟精度相差不大,但在G1、G3和G4层次上前者明显高于后者.研究还表明,工矿企业类型在区分土壤Zn含量高低(G1、G2和G3、G4、G5)层次上起主要作用,G1和G2之间,G3、G4和G5之间的土壤Zn含量与pH值、土壤类型和土地利用方式有关.  相似文献   
1000.
我国日益增长的危险废物对于环境安全和人体健康都构成极大威胁,如何高效、科学的对危险废物从产生到最终处置的全过程进行管理和决策是我国危险废物管理工作面临的重要问题。区域危险废物的管理和环境风险控制是一个涉及到废物特性、自然环境和社会经济等诸多因素的综合决策过程。文章通过综合考虑危险废物处理处置过程中的环境影响因素、经济因素和环境风险因素,结合空间分析技术和多目标决策的方法,设计了一个危险废物多目标空间决策支持模型,并以广州为例进行了模拟应用。危险废物管理的决策者根据不同的侧重点,通过本模型在备选废物处理处置中心中确定建设地点,同时能够使用本模型选择危险废物的最佳运输路径。本模型为危险废物管理和决策支持提供了一种直观、科学和实用的支持,具有一定的理论和现实意义。  相似文献   
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