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951.
企业危险化学品仓储管理的探讨 总被引:1,自引:0,他引:1
化学品的仓储作为化学品生命周期的一个重要阶段,它的安全管理是化学品安全管理的一个重要环节.探讨了企业危险化学品安全储存管理的一般要求和工作程序. 相似文献
952.
水工建筑中,据岩体的强度特性和内水压力的大小,精确确定有压隧硐上覆岩层最小厚度是非常重要的。文章在对经典方法进行评述的基础上,引入反映岩体非线性破坏特征的经验强度准则,视有压隧硐为内水压力和岩体初始应力联合作用的弹性体,据经验准则对岩体破坏的表述,理论推导了坚硬无裂缝岩体中有压隧硐上覆岩层最小厚度计算公式。最后,以简单算例说明文中方法。 相似文献
953.
954.
Shaojun Chen 《Chemistry and Ecology》2019,35(5):431-444
A leaf-bag field experiment was conducted to investigate the decomposition and release of nutrients from leaves of two aquatic macrophytes (floating-leaved Trapa bispinosa and submerged Vallisneria natans) deposited in the four vertical locations (i.e. air-water interface, AW; sediment-water interface, SW; buried at a depth of 10?cm, B10; buried at a depth of 20?cm, B20) of littoral zone in Nanhu Lake, China, for 60 days from July to August 2015. Leaf initial quality significantly influenced mass loss and nutrient release except TN (total nitrogen) remaining. Compared to V. natans, T. bispinosa leaves decomposed faster under the same treatments. The decomposition was greatly affected by both leaf chemical quality and the location of deposition. With the increasing depth of vertical locations, leaf biomass loss and nutrient release of both T. bispinosa and V. natans decreased. In addition, initial N:P ratio and cellulose were the major determinants for decomposition in AW and SW treatments while total phenol in B10 and B20. Our results suggest that the combined effect of leaf chemical quality and burial could mediate macrophyte mass loss and release of nutrients and carbon, which in turn can influence organic matter accumulation and nutrient cycling in shallow freshwater lakes. 相似文献
955.
李永存 《中国安全生产科学技术》2005,1(4):100-102
对铝电解多功能天车大修、技改作业中存在的危险因素进行了分析,指出大修、技改中存在的不安全因素,及其诱发工伤事故的原因,并提出了保证铝电解多功能天车大修、技改安全作业的对策。 相似文献
956.
危险货物道路运输探析 总被引:1,自引:1,他引:1
本文介绍了国内外危险货物道路运输的现状,归纳总结了危险货物道路运输事故的特点,阐述了我国当前危险货物道路运输存在的主要问题,对危险货物道路运输事故的影响因素进行了全面分析,并提出了相应对策措施.本文的分析可以为政府部门和运输业户控制和管理危险货物道路运输系统提供有益的参考. 相似文献
957.
在利用间歇式液相本体法工艺生产聚丙烯时,易产生大量废水,包括闪蒸水环真空泵排放水、聚合釜轴封冷却水排放水、聚合升温用热水罐溢流水等。应最大限度地减少废水的排放量。已经采取的废水减排措施包括:对于真空泵逐渐调小供水量(即减少了排放量);将轴封冷却水收回重复利用;维持热水罐的水位稳定,避免产生溢流。采取上述措施在满足生产要求的同时,最大限度地减少了废水排放量。 相似文献
958.
Briant A. Kimball Paul K. Christensen 《Journal of the American Water Resources Association》1996,32(3):531-540
ABSTRACT: The Hanging Gardens are a unique feature of Zion National Park. Knowledge of the source and residence time of water discharging from the Hanging Gardens is necessary to help preserve these features. Ground-water chemical and isotopic data distinguish the discharge from seeps and springs into two groups, one of low and one of high conductivity. Water with low conductivity likely originates as recharge near the seeps and springs, and it only interacts with the Navajo Sandstone. High conductivity water, on the other hand, originates as recharge on the tops of plateaus to the east, where it interacts with marine rocks of the Carmel Formation. Carbon dating of these ground waters indicates that the low conductivity water is essentially modern recharge, while the high conductivity water was recharged 1,000 to 4,000 years ago. 相似文献
959.
Manoutchehr Heidari Keros Cartwrighi 《Journal of the American Water Resources Association》1981,17(4):614-622
: The danger to the environment associated with the injection of liquid industrial wastes into a deep, confined, subsurface rock formation may arise from the transport of the waste laterally or vertically in the formation. The pattern of lateral transport, which can take place as a result of convection as well as dispersion and diffusion, can be determined by an approximate analytical solution to the mass transport equation. Vertical transport may take place through both natural fractures and fractures created by hydrostatic stresses generated around the well during injection. To determine the stresses, we used the finite element method to get a numerical solution of the flow equation. We applied a solution of the flow equation to calculate the stress buildup and decay for the Jones & Laughlin Steel Corporation's injection well near Hennepin in Putnam County, Illinois. According to our computations, the stress buildup due to injection is about 0.16 pounds per square inch per foot - psi - (0.362 Newton per square centimeter per meter), which, added to normal pressure, makes an estimated total stress of 0.60 psi/ft (1.36 Newton/cm2/m). That pressure is insufficient to cause fracturing of the Cambrian Eau Claire aquitard, the confining bed for the disposal zone. 相似文献
960.
Paul H. Whitfield 《Journal of the American Water Resources Association》1982,18(2):203-210
ABSTRACT: Four simple methods for estimating mass transport are evaluated in terms of the assumptions made about the properties of the data set being analyzed. The basic difference between the four methods considered are their assumptions regarding the manner in which concentration is distributed and the relationship between concentration and discharge. The most precise estimates of mass transport into and out of Schwatka Lake, Yukon Territory, were obtained from the model which assumes that concentration is log normally distributed and independent of discharge. 相似文献