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491.
Abstract Along with the rapid growth of economy in the postreform period after 1979, China has faced severe problems of resource overusing and environmental degradation which would threaten the sustainable development of economy and society. This article explores an effective mechanism of managing resource and environment in China. It examines some major resource and environmental issues, and constructs a framework of institution innovation to cover three sectors (government, market and society). In addition, the article analyzes their experience and evaluation in resource management and environmental conservation during the transitional period. We argue that the combination of market regulation, government intervention and public participation is an effective way of allocating resource and protecting environment. Some suggestions are put forward to balance the relationship between them, including coordinating role of government and market, building platform for market operation and creating an atmosphere of public participation. 相似文献
492.
The study looks into the occupational safety and working conditions among bus drivers in Metro Manila, the Philippines. Quantitative data were collected through survey interviews of 95 bus drivers using the stratified sampling technique. Results showed that bus drivers worked an average of 16?h/day and were engaged in risky driving behaviors such as over-speeding and road racing in order to reach their quota for the day. Fifty-nine percent experienced work-related accidents, with a mean of three accidents. The most common accident was hitting another vehicle followed by side swipe. The accidents were blamed on other drivers, followed by vehicle defect, inattentiveness and tiredness/micro-sleep or sudden involuntary sleep while driving. The most common health symptoms experienced by the bus drivers were fatigue, back pain, and cough and colds. This study underlines the need for an occupational health and safety program for bus drivers in the Philippines. 相似文献
493.
494.
In the work presented in this paper, the propagation direction of the pressure waves generated during combustion-induced Rapid Phase Transition (cRPT) was investigated. To this end, explosion tests were performed for CH4/O2/N2/CO2 mixtures in a tubular reactor. Ignition was provided at the top or at the bottom of the vessel. Pressure time histories were recorded by two transducers positioned one at the top and the other one at the bottom.Results have shown that the preferential direction for the pressure waves is that of the flame propagation. When the cRPT phenomenon is weak, an over-adiabatic pressure peak (of around 10–20 bar) can be measured by only one transducer and, in particular, by the transducer far away from the ignition point. Conversely, when the cRPT phenomenon becomes severe, over-adiabatic peaks (as high as 250 bar) can be detected even by the other transducer. Such peaks are the result of separate cRPT events that occur very close to the transducers and, thus, are not damped along the vessel length. In spite of the fact that the upward flame propagation is faster, the cRPT phenomenon is more severe in the case of downward flame propagation. 相似文献
495.
滨海旅游作为我国海洋经济的龙头产业,在产业规模快速发展和产业地位稳步提升的同时,面临着日趋严重的资源环境约束问题.基于生态文明理念与滨海旅游转型发展的作用关系,阐述了生态文明建设与滨海旅游发展方式转变的内在关联,探讨了我国沿海地区旅游碳排放量现状特征和发展水平,提出生态文明理念下我国滨海旅游产业低碳化转型发展的对策建议. 相似文献
496.
提出一种基于多元堆叠长短时记忆网络-差值分析(MSLSTM-DA)模型对地表水质异常数据进行报警的方法.该方法首先建立MSLSTM模型对水质指标数据进行预测,再基于预测结果的残差分布建立DA模型,并确定各个指标的数据异常阈值,当实测数据与预测数据差值大于阈值时进行数据报警.以长江流域监测断面的水质数据进行了方法有效性验证.结果表明,构建的预测模型对5个指标的MAE、MAPE均值比BP神经网络预测模型降低21.0%,17.8%,比LSTM模型降低16.8%,17.9%.皮尔逊系数均值比BP神经网络、LSTM模型的分别高5.9%,4.4%.5个指标共检出水质异常数据37条,其中34条经人工判断确实存在有异常,报警准确率高达91.9%. 相似文献