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101.
对近10 a来国内外有关气候变化经济学研究成果作了综述。气候变化经济学是一门研究人类干预气候变化过程中涉及经济过程的学科。当前的研究热点包括气候变化的经济影响、适应措施的成本和收益、国际合作机制和涉及代际公平的折现率选取。 在研究方法上,对得到广泛运用的成本收益分析法和碳税机制作了详细的评述。在应用层面上,欧美发达国家在城市气候变化经济评估系统建立和碳税征收方面都有成功的应用,但我国在这方面的实践还处于起步阶段。对于我国气候变化经济学领域的研究来说,比较适合在发达省份以市域或省域为单位开展成本收益评估,发展中省份则应将更多关注放在评估气候变化可能造成的经济损害及相应的防范措施。此外,我国也应关注在欧盟地区实施较为成功的碳税政策,虽然目前在中国开征碳税的可能性较低,但是对碳税在中国实施的可行性、税率选取及立法保障机制等方面的探讨和研究仍是必要的 相似文献
102.
Fenton process, as a pretreatment method, was found to be effective in the primary treatment of mature/medium landfill leachate. However, the main problem of the process is the large amount of produced sludge that requires an accurate feasibility evaluation for operational applications. In this study, the response surface methodology was applied for the modeling and optimization of Fenton process in three target responses, (1) overall COD removal, (2) sludge to iron ratio (SIR) and (3) organics removal to sludge ratio (ORSR), where the latter two were new self-defined responses for prediction of sludge generation and applicability assessment of the process, respectively. The effective variables included the initial pH, [H2O2]/[Fe2+] ratio and Fe2+ dosage. According to the statistical analysis, all the proposed models were adequate (with adjusted R2 of 0.9116–0.9512) and had considerable predictive capability (with prediction R2 up to 0.9092 and appropriate adequate precision). It was found that all the variables had significant effects on the responses, specifically by their observed role in dominant oxidation mechanism. The optimum operational conditions obtained by overlay plot, were found to be initial pH of 5.7, [H2O2]/[Fe2+] ratio of 17.72 and [Fe2+] of 195 mM, which led to 69% COD removal, 2.4 (l sludge/consumed mole Fe2+) of SIR and 16.5 (gCOD removed/l produced sludge) for ORSR in verification test, in accordance with models-predicted values. Finally, it was observed that [H2O2]/[Fe2+] ratio and Fe2+ dosage had significant influence on COD removal, while Fe2+ dosage and [H2O2]/[Fe2+] ratio had remarkable effects on SIR and ORSR responses, respectively. 相似文献
103.
选择北京市四家锅炉厂的电焊工56名,即从事手把焊、氩弧焊、CO2气体保护焊、电弧气爆等特种工种作业人员。通过调查,提出单项四级评分标准,再依模糊数学模型,进行综合评价。按B=A·R,求得B中最大元为0.707。最后总评为甲级。此结果与权数分配有关。此方法,可为劳动卫生管理(防护措施评级)提供依据。 相似文献
104.
Fuzzy数学在人-机-环境系统工程研究中的应用 总被引:1,自引:0,他引:1
孙洪元 《中国安全科学学报》1995,5(6):33-33
综述了模糊数学在航天人机环境系统工程中的应用和发展。内容包括急性缺氧反应综合评定,人机系统中的控制模型,通风服研制和鉴定以及人体。心脏功能评价等研究领域中模糊数学的应用方法和作用。其研究方法对于一般人机工程的建模和分析具有积极意义。 相似文献
105.
把模糊计算理论和有色Petri网有机地结合起来 ,提出了一种模糊颜色Petri网诊断表决算法 ,把该算法应用于DVP的软件模型 ,使之具有故障容忍和表决的能力。笔者对以模糊颜色Petri网为核心的DVP软件模型表决算法进行了较为深入的探讨 ,该模型对提高软件系统的安全性和可靠性具有实际意义。 相似文献
106.
安全等级特征量及其计算方法 总被引:17,自引:2,他引:15
指出了目前用模糊评价法确定系统的安全等级所存在的问题和不足之处。分别运用模糊随机变量理论和模糊集理论而提出了安全等级模糊随机特征量和安全等级模糊特征量的概念及其计算方法。安全等级特征量及安全等级变量,均为安全等级取值论域上的模糊子集,而并非是一个确定的点。还给出了安全等级的绝对可能性和相对可能性的计算方法。实例表明,笔者所提出的安全等级特征量及可能性的计算方法是科学的、合理的 相似文献
107.
Tiancheng Shang Xiaotong Sun Peihong Liu Junqing Gao 《International Journal of Green Energy》2020,17(3):196-207
ABSTRACTA credit risk identification model is established to examine the credit status of Energy performance contracting (EPC) project clients (i.e., energy-using companies) in China based on rough set theory. The model is verified with data from 120 listed companies at different times. Study shows that lack of credit is one of the main obstacles to the implementation of EPC projects, and information asymmetry is the main reason for this lack of credit among potential clients in China. The credit risk identification method based on rough set theory can make up for the shortcomings of existing EPC projects in terms of credit risk identification, including redundant information and indicators, and unclear decision rules. Credit risk identification indicators of clients are dynamic. The research results can help energy service companies (ESCOs) determine the credit status of clients, facilitate cooperation between ESCOs and clients, and help explain the various dynamics of clients’ credit risk identification indicators over time. 相似文献
108.
小城镇灾害易损性分析与评估 总被引:7,自引:0,他引:7
随着我国城镇化进程的加快 ,小城镇的防灾减灾问题逐步引起社会的关注 ,而小城镇易损度分析和评价是灾害危险性评价的重要组成部分 ,也是小城镇决策部门制定防灾减灾规划的重要依据 ;笔者在综合分析了小城镇的自然易损性、经济易损性及社会易损性的基础上 ,选取相应的灾害指标和社会经济指标 ,应用多级模糊综合评判方法 ,对小城镇的易损程度作出了评估 ,从而为小城镇制定相应防灾、减灾对策提供科学依据。 相似文献
109.
110.
Rough Set Rule Induction for Suitability Assessment 总被引:4,自引:0,他引:4
Berger PA 《Environmental management》2004,34(4):546-558
The data that characterize an environmental system are a fundamental part of an environmental decision-support system. However, obtaining complete and consistent data sets for regional studies can be difficult. Data sets are often available only for small study areas within the region, whereas the data themselves contain uncertainty because of system complexity, differences in methodology, or data collection errors. This paper presents rough-set rule induction as one way to deal with data uncertainty while creating predictive if–then rules that generalize data values to the entire region. The approach is illustrated by determining the crop suitability of 14 crops for the agricultural soils of the Willamette River Basin, Oregon, USA. To implement this method, environmental and crop yield data were spatially related to individual soil units, forming the examples needed for the rule induction process. Next, four learning algorithms were defined by using different subsets of environmental attributes. ROSETTA, a software system for rough set analysis, was then used to generate rules using each algorithm. Cross-validation analysis showed that all crops had at least one algorithm with an accuracy rate greater than 68%. After selecting a preferred algorithm, the induced classifier was used to predict the crop suitability of each crop for the unclassified soils. The results suggest that rough set rule induction is a useful method for data generalization and suitability analysis. 相似文献