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711.
城市群发展阶段的划分与评判——以长株潭和泛长株潭城市群为例 总被引:1,自引:0,他引:1
城市群的发展阶段是研究城市群或城市群规划建设中首先需要搞清楚的问题.鉴于目前对城市群发展阶段的划分没有统一标准,综合国内外对城市群发展演化阶段的划分方法,借鉴生命成长规律,把城市群发展划分为雏形发育阶段、快速发育阶段、趋于成熟阶段和成熟发展阶段,并对城市群各发展阶段的特征进行了概述.结合城市群各发展阶段的特征,构建了定性指标与定量指标相结合的城市群发展阶段评判指标体系,并制定了指标评判的界定标准.最后,运用模糊综合评判法和层次分析法,对长株潭城市群与泛长株潭城市群的发展阶段进行了实证评判.评判结果表明,长株潭城市群已处于快速发育阶段,但仍处于快速发育阶段的中前期;泛长株潭城市群仍处于雏形发育阶段,但已处于雏形发育阶段的中期. 相似文献
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713.
摘要:通过河南鹤壁丰鹤火电厂2×600MW湿法脱硫的工程实践,结合国内其他脱硫工程的应用经验.对湿法脱硫工艺中增压风机的运行控制进行探讨。 相似文献
714.
崇明东滩鸟类生境适宜性空间模糊评价 总被引:3,自引:0,他引:3
利用模糊数学方法、地理信息系统(GIS)和遥感(RS)技术,采用定性和定量相结合的方法构建了鸟类生境适宜性空间模糊评价模型,解决了隶属函数的空间化问题,扩展了模糊数学方法在自然保护区空间地理事物评价中的应用。通过评价几种鸟类的生境适宜性,结果表明:大多数鸟类在海三棱藨草外带和光滩适宜性最好,由此向内陆或水域方向适宜性降低,这一显著变化与崇明东滩环境演化趋势有着密切的关系;由于鸟类生活习性的差异,不同鸟类的空间适宜性范围存在一定的差异性;已有的保护区功能区划未能充分考虑当前鸟类生境适宜性情况,生境适宜性的评价结果可以为崇明东滩保护区的功能区划提供技术性指导。 相似文献
715.
Due to the increasingly serious environmental pollution and destruction,especially humans’ unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more and more attention of the researchers.Aiming at evaluating its ecological and economic system health,a multi-objective evaluation framework called PressureState-Response(PSR) was established to describe the ecological and economic health situations.Meanwhile,an integrative set pair model combining set pair analysis(SPA) and fuzzy analytic hierarchy process(FAHP) was proposed to assess the ecological and economic system.Then the EES status of five northwest provinces(Shanxi,Gansu,Qinghai,Ningxia and Xinjiang) of Northwest region in China was evaluated during 1985 to 2009.The EES development trends of five provinces are obtained.In general,the health values of five provinces showed a rising trend.The health values of five provinces grew rapidly during 1985 to 2000.After 2000,the health values of five provinces still followed the present growth trend,but the growth is relatively smooth.The results show that the method proposed is effective for assessing the health of ecological and economic system. 相似文献
716.
云南省冰冻灾害气象条件及风险评估——基于模糊信息分配方法的研究 总被引:1,自引:0,他引:1
利用1959—2008年云南省125个气象站的逐日资料,采用模糊信息分配方法和三分段法进行了雨、雾淞(冰冻)天气发生的气象条件研究;基于模糊信息分配和超越极限概率法进行了云南冰冻灾害气候风险评估和风险区划研究。结果表明:模糊信息分配方法用于概率密度估计,可减少分析、评估误差,且不需要假定数列总体概率分布函数,就能得出较为接近实际概率密度分布的分析和评估结果;雨、雾淞(冰冻)出现当日最低气温≤1℃的气候概率达99.8%,最低气温≤1℃是出现雨、雾淞(冰冻)天气的阈值;当温度条件达到时,微量以上降水、日照时数≤1 h、日平均相对湿度大于80%是出现雨、雾淞(冰冻)的阈值。云南省大部分地区(96个站,占全省总站数的77%)没有出现冰冻灾害的风险,无风险的区域分布在云南省的中、西部和南部地区;冰冻灾害风险较大的是滇东北和滇东地区,其中有12个站累积概率值在50%~100%之间,有年年出现或2年1遇的气候风险,风险较大,特别是镇雄、鲁甸2个县的概率值为100%,有年年出现冰冻灾害的气候风险,风险很大。 相似文献
717.
718.
Ahmad Mayyas Mohammed T. Hayajneh 《International Journal of Sustainable Engineering》2016,9(5):292-304
In the classical multiple attribute decision-making or MADM methods, the ratings and the weights of the criteria are known precisely. However, in eco-material selection exercises, the available data are typically inadequate because of the selection dual quantitative and qualitative natures. Some of the qualitative selection criteria can be rated in several classes rather being expressed by exact numerical values; hence the application of fuzzy concepts in decision-making seems attractive to deal with such kind of ratings. Thusly, the presented study attempts to propose an eco-material selection approach specific to the automobile body panels using a fuzzy technique for order preference by similarity to ideal solution (TOPSIS), to incorporate both numerical and rating-based criteria into one holistic sustainability model. TOPSIS and fuzzy logic can aid the material selection process in translating the design goals and parameters into usable numbers that in turn can be used to rank candidate materials in their closeness to the ideal solution. An additional uniqueness of this study stems from using the fuzzy-TOPSIS as a scoring tool without any assigned weights for the different selection attributes, in order to avoid the bias that is typically associated with other classical MADM, such as quality function deployment, analytical hierarchy process and digital logic. 相似文献
719.
两类新型神经网络及其在安全评价中的应用 总被引:3,自引:2,他引:1
详细讨论小波神经网络(WNN)和模糊神经网络(FNN)的构造以及训练学习过程,并针对安全评价问题分别完成算例。典型算例表明:小波神经网络具有很好的逼近与映射能力,并且有很强的泛化能力;模糊神经网络将模糊数学与人工神经网络相互融合起来,有效提升了系统的智能功能。两类新型神经网络使得人-机-环境系统工程中的许多安全评价问题有了更广泛的量化工具,并具有安全评价的量化较准确的特点。 相似文献
720.
Based on the analysis of hanging rivers' actuality in the lower Yellow River and researches related to the evaluation of dike breach risks, it is put forward that the influencing factors of dike beach risks in the lower Yellow River should involve four aspects, the flow and sediment movement, the regional crustal stability, the variation of river regime and the stability of river dikes. With this, the evaluation indexes system of dike breach risks is established, and with the support of geographic information systems technology, the model of multi-hierarchical fuzzy comprehensive judgment is applied to estimate the dike beach risks of the hanging rivers in the lower Yellow River under different flood conditions. The evaluation results of dike breach risks show the following distributing regularities of dike breach risks in the lower Yellow River: (1) Dike breach risks increase with the increase of the flood. (2) Dike breach risks decrease with the changes of river patterns along the channel. (3) There are great risks of dike breach in the wandering reaches, and it is relatively higher in the south bank than in the north in wandering reaches. (4) There is a higher dike breach risk in the north bank than in the south in winding reaches. Simultaneously, the evaluation results manifest that the evaluation indexes system established from the flow and sediment movement, the regional crustal stability, the variation of river regime and the stability of river dikes can represent the actual situation of the lower Yellow River more comprehensively. The application of multi-hierarchical fuzzy comprehensive judgment can preferably resolve the problem of hanging river dike breach, which has numerous influencing factors and complicated functionary mechanisms. The applications of geographic information systems technology with powerful spatial analysis functions make dike beach risks quantificationally displayed in different spatial positions, and reflect the differences of dike beach risks in different spatial positions of the channel in the lower Yellow River. 相似文献