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611.
稳定型含氯消毒剂的稳定性及消毒效果研究 总被引:3,自引:0,他引:3
用传统含氯消毒剂与一种磺酸基化合物络合,形成氯稳定体系的水溶液。对该消毒剂在6个月内的有效氟、pH值、氧化还原电位的监测结果表明:其稳定性相当好,pH基本保持不变,有效氯及氧化还原电位的变化率分别为0.51%与9.47%。定量消毒试验结果表明,稳定型含氟消毒剂的消毒能力强,其消毒能力仅略低于二氟异氰尿酸钠等含氯消毒剂,存放6个月后,对表皮葡萄球菌的杀灭率无明显变化。对加5%牛血清白蛋白的表皮葡萄球菌20min的杀灭率无变化。这种稳定型的含氯消毒剂将具有广阔的应用前景。 相似文献
612.
613.
Qingsong Wang Jinhua Sun Xiaolin Yao Chunhua Chen 《Journal of Loss Prevention in the Process Industries》2006,19(6):561-569
With the extensive applications of lithium-ion batteries, many batteries explosion accidents were reported. The thermal stability of lithium-ion battery electrolyte could substantially affect the safety of lithium-ion battery. The C80 micro calorimeter was used to study the thermal stability of several commonly used organic solvents and electrolytes. The samples were heated in argon atmosphere and air atmosphere, respectively. The chemical reaction kinetics was supposed to fit by an Arrhenius law, then the self-accelerating decomposition temperature was calculated. It is found that most of the samples are stable in argon atmosphere while decomposing in air atmosphere, and the single organic solvent is more stable than the electrolyte generally. 相似文献
614.
615.
火灾环境下具有弹性支座钢构件的稳定性能 总被引:5,自引:0,他引:5
根据弹性稳定理论原理研究了具有弹性支座钢结构构件在火灾环境下的静力特性问题 ,导出了高温下钢构件的静力稳定临界荷载和长度计算式 ,并讨论了温度、杆件的侧向弹簧刚度、杆长、保护层厚度等因素对杆件静力稳定临界荷载和长度的影响 ,分析表明 ,杆件的侧向弹簧刚度、杆长、保护层厚度对杆件的稳定承载力影响较大 ,并探讨了在实际工程中如何减小结构失稳的问题。 相似文献
616.
Polyisocyanurate foams were prepared from polymeric 4,4-diphenylmethane diisocyanate (MDI), soy polyol and polypropylene oxide polyol by varying isocyanate index from 110 to 350. The higher isocyanate index produced polyisocyanurate foams with higher thermal stability, improved flame resistance, tensile strength, higher modulus, and higher glass transition. Soy-based foams displayed better thermal stability, lower flammability, higher rigidity (modulus) and higher compression strength than those based on the propylene oxide polyols of the same molecular weight and functionality. 相似文献
617.
Many marshes in the Gulf Coast Chenier Plain, USA, are managed through a combination of fall or winter burning and structural
marsh management (i.e., levees and water control structures; hereafter SMM). The goals of winter burning and SMM include improvement
of waterfowl and furbearer habitat, maintenance of historic isohaline lines, and creation and maintenance of emergent wetlands.
Although management practices are intended to influence the plant community, effects of these practices on primary productivity
have not been investigated. Marsh processes, such as vertical accretion and nutrient cycles, which depend on primary productivity
may be affected directly or indirectly by winter burning or SMM. We compared Chenier Plain plant community characteristics
(species composition and above- and belowground biomass) in experimentally burned and unburned control plots within impounded
and unimpounded marshes at 7 months (1996), 19 months (1997), and 31 months (1998) after burning. Burning and SMM did not
affect number of plant species or species composition in our experiment. For all three years combined, burned plots had higher
live above-ground biomass than did unburned plots. Total above-ground and dead above-ground biomasses were reduced in burned
plots for two and three years, respectively, compared to those in unburned control plots. During all three years, belowground
biomass was lower in impounded than in unimpounded marshes but did not differ between burn treatments. Our results clearly
indicate that current marsh management practices influence marsh primary productivity and may impact other marsh processes,
such as vertical accretion, that are dependent on organic matter accumulation and decay. 相似文献
618.
619.
Vincent H. Y. Tam Brian Corr 《Journal of Loss Prevention in the Process Industries》2000,13(6):588-447
The design of topsides against explosions requires the definition of a design over-pressure, however, these values are often treated as deterministic and there is a wide variation within the industry in the treatment and interpretation of the loads.
This paper advocates the adoption of a number of limit state for explosion loading. Events of different magnitudes are differentiated on the basis of frequency and linked to appropriate degree of reliability thus avoiding disproportionate effects from minor events.
The two principal limit states considered are a limit state for all the safety critical systems for relatively high frequency events and a survival condition for low probability events. Parallels are drawn from other branches of engineering where extreme loads have to be designed for. 相似文献
620.