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981.
开发建设项目对生物多样性的影响评价方法构想 总被引:5,自引:0,他引:5
开发建设项目的经济利益与生物多样性保护之间的矛盾日益突出,迫切需要在环境影响评价工作中解决。本文利用模糊综合评价建立起一套方法体系来解决这一现实问题。 相似文献
982.
983.
针对垃圾渗滤液生化尾水中仍含有较高浓度的难生物降解COD、NH4+-N和NO2--N,无法满足现行排放标准的问题,采用基于硫酸根自由基的高级氧化技术(SR-AOP)对生化尾水进行深度处理.考察了pH值、温度、FeSO4和过硫酸钠浓度对TOC和TN去除效果的单独作用及交互作用.结果表明,影响因子对于处理效果的贡献排序为:pH值>温度>过硫酸钠浓度,各因素对TOC的去除有显著性影响,而对TN的去除没有显著性影响.各因素的复合效应为:TN去除效果影响:温度+过硫酸钠浓度>pH+过硫酸钠浓度>温度+pH, TOC去除效果影响:温度+pH>pH+过硫酸钠浓度>温度+过硫酸钠浓度.实验最终确定SR-AOP的最佳条件为:pH=5,温度为30℃,过硫酸钠浓度为0.5g/L,催化剂FeSO4剂量为3.8g/L,该条件下TOC去除率为35.5%,TN去除率为16.9%,同时可以显著提高出水BOD5/COD.因此,通过SR-AOP深度处理可以去除生化处理尾水大部分COD和TN,并大幅提高B/C比,为后续与适当的生化处理工艺组合进行达标处理奠定了良好的基础. 相似文献
984.
随机规划方法已成为解决不确定条件下高硫炼油装置气体检测报警仪布置优化问题的重要途径,而构建接近真实情况的泄漏场景集则是实现随机规划的基础。目前,有毒气体泄漏场景集构建方面的研究鲜有报道,且传统以典型泄漏场景为代表的做法未能体现真实风险。为此给出一种融合泄漏概率和风场联合分布概率的定量构建硫化氢泄漏场景集的方法,使场景集包括重要泄漏场景并运用DNV的LEAK软件和历史气象数据定量预测场景的实现概率,为实现后续的气体泄漏检测报警仪布置随机规划提供技术支持。并以某柴油加氢装置为例,定量构建其硫化氢泄漏场景集,为后续的气体检测报警仪布置优化及其它基于定量风险分析的控制决策提供支持。 相似文献
985.
新型高分子螯合-絮凝剂制备条件的响应面法优化 总被引:3,自引:0,他引:3
以壳聚糖为原料,采用化学合成法将二硫代羧基引入到其高分子链上,制备出一种新型高分子螯合-絮凝剂二硫代羧基化壳聚糖(R′-N-(C=S)-SNa,简称DTCTS).以水样中Cd(Ⅱ)的去除率为考察对象,在单因素实验法的基础上,选取了制备DTCTS的主要影响因素,并采用中心复合设计实验和响应面分析法对DTCTS制备条件进行了优化.结果表明,建立的二次多项式模型回归性显著而失拟项不显著,决定系数R2为0.9829,模型拟合性良好;DTCTS最佳制备条件为:反应物CTS/CS2/NaOH摩尔比1:1.5:2、预反应时间30min、主反应温度60℃,此条件下制备的DTCTS对Cd(Ⅱ)的去除率可达99.52%,与模型预测值相对偏差为0.05%,模型可靠. 相似文献
986.
In this research, a framework combining lean manufacturing principles and fuzzy bow-tie analyses is used to assess process risks in chemical industry. Lean manufacturing tools and techniques are widely used for eliminating wastes in manufacturing environments. The five principles of lean (identify value, map the value stream, create flow, establish pull, and seek perfection) are utilized in the risk assessment process. Lean tools such as Fishbone Diagram, and Failure Mode and Effect Analysis (FMEA) are used for risk analysis and mitigation. Lean principles and tools are combined with bow-tie analysis for effective risk assessment process. The uncertainty inherent with the risks is handled using fuzzy logic principles. A case study from a chemical process industry is provided. Main risks and risk factors are identified and analyzed by the risk management team. Fuzzy estimates are obtained for the risk factors and bow-tie analysis is used to calculate the aggregated risk probability and impact. The risks are prioritized using risk priority matrix and mitigation strategies are selected based on FMEA. Results showed that the proposed framework can effectively improve the risk management process in the chemical industry. 相似文献
987.
《Process Safety and Environmental Protection》2014,92(5):390-405
With the increasing pressures imposed upon industries on the environmental impacts of the manufacturing industry and chemical processes, numerous methodologies have been developed for the quantification, assessment and minimisation of waste and emissions. Meanwhile, methods for the simultaneous maximisation of economic performance within a product life cycle have also been developed. Similarly, various methodologies for screening of process alternatives based on the above factors have also been developed. However, the human lives put at risk in a supply chain constituting a life cycle tend to be overlooked as a factor of assessment, selection and optimisation of the process. Despite having life cycle assessment (LCA) methodologies for environmental assessment, no methodology has been developed for the minimisation of work-related casualties due to the unpredictable nature of workplace accidents. To address this problem, this paper develops a multi-objective optimisation model that utilises realistic statistical data for estimating the best possible pathway. The model results in the least potential fatality directly involved within the product life cycle while simultaneously minimising operating costs throughout the entire life cycle. A case study involving the utilisation of palm-based biomass formed for the production of value-added green products in Malaysia is used to demonstrate the model. 相似文献
988.
《Process Safety and Environmental Protection》2014,92(4):338-345
In this paper, a general procedure to deal with uncertainties in each stage of consequence modeling is presented. In the first part of the procedure, the sources of uncertainty are identified and confirmed by sensitivity analysis for the source term, dispersion, physical effects and consequence analysis. While the second part comprises an application of the fuzzy logic system to each step of the consequence modeling. The proposed procedure is verified by the case study for a pool fire liquefied natural gas (LNG) on water. The results in terms of thermal radiation distances are compared with calculations obtained using the Monte Carlo method and with experimental data. The consequence model based on fuzzy logic approach provides less uncertain and more precise results in comparison to the deterministic consequence model. 相似文献
989.
《Process Safety and Environmental Protection》2014,92(6):739-749
Simultaneous investigation of environmental emissions and machining aspects of electrical discharge machining process is essential for achieving hygienic and efficient machining. The main objective of the present work is to experimentally investigate and analyze the aerosol emission rate and the material removal rate from a die sinking electrical discharge machining process for three commonly used work piece materials viz., tool steel, mild steel and aluminum using Taguchi methodology of Experimental Design in order to suggest suitable process conditions for green manufacturing. The aerosol emission profile of all workpiece materials was found to be closely related to the material removal profile. A significant variation in emission and material removal rate was observed for workpiece materials which may be accorded to the variation in melting and vaporization temperatures. It was also observed that majority of aerosol constituents evolved from workpiece materials and that the constituents with low melting points were having high relative concentration in the aerosol emitted. The study introduced a parameter, the relative emission rate for comparing the emission for various process parameters and workpiece–tool material combinations. The favorable machining parameters for each material were then identified by employing signal to noise ratio analysis of the relative emission rate. 相似文献
990.
采空区遗煤自燃严重威胁着煤矿的安全生产,因此为了提前采取有针对性的防范措施,有必要进行遗煤自燃危险性评价。采用层次分析法确定各评价指标的权重,根据集对分析法的基本原理结合采空区遗煤自燃的具体情况,对集对理论进行了扩展,并重新构建了基于确定不确定信息的分析模型。将该模型应用于新集二矿210610工作面,评价结果表明该模型分析过程合理、置信度高,为采空区遗煤自燃危险性评价提供了一种新的方法,同时也为煤矿有针对性的采取安全防范措施提供了参考。 相似文献