全文获取类型
收费全文 | 2244篇 |
免费 | 204篇 |
国内免费 | 760篇 |
专业分类
安全科学 | 229篇 |
废物处理 | 57篇 |
环保管理 | 112篇 |
综合类 | 1743篇 |
基础理论 | 587篇 |
污染及防治 | 203篇 |
评价与监测 | 214篇 |
社会与环境 | 35篇 |
灾害及防治 | 28篇 |
出版年
2024年 | 31篇 |
2023年 | 75篇 |
2022年 | 110篇 |
2021年 | 141篇 |
2020年 | 92篇 |
2019年 | 130篇 |
2018年 | 79篇 |
2017年 | 84篇 |
2016年 | 112篇 |
2015年 | 132篇 |
2014年 | 220篇 |
2013年 | 146篇 |
2012年 | 163篇 |
2011年 | 177篇 |
2010年 | 133篇 |
2009年 | 117篇 |
2008年 | 145篇 |
2007年 | 147篇 |
2006年 | 111篇 |
2005年 | 89篇 |
2004年 | 85篇 |
2003年 | 81篇 |
2002年 | 65篇 |
2001年 | 61篇 |
2000年 | 55篇 |
1999年 | 62篇 |
1998年 | 40篇 |
1997年 | 58篇 |
1996年 | 70篇 |
1995年 | 51篇 |
1994年 | 42篇 |
1993年 | 17篇 |
1992年 | 27篇 |
1991年 | 19篇 |
1990年 | 26篇 |
1989年 | 12篇 |
1988年 | 2篇 |
1987年 | 1篇 |
排序方式: 共有3208条查询结果,搜索用时 937 毫秒
991.
992.
993.
994.
A mesocosm experiment was conducted to investigate whether plant coexistence affects cadmium (Cd) uptake by plant in contaminated soil.Tobacco (Nicotiana tabacum L.var.K326) and Japanese clover (Kummerowia striata (Thunb.) Schindl.) were used.Cadmium was applied as 3CdSO 4 ·8H 2 O in solution at three levels (0,1,and 3 mg/kg soil) to simulate an unpolluted soil and soils that were slightly and moderately polluted with Cd.Tobacco (crop),Japanese clover (non-crop),and their combination were grown under each C... 相似文献
995.
Bisphenol A (BPA) is a chemical with high production volume and wide applications in many industries. Although BPA is known
as an endocrine disruptor, its toxic mechanisms have not been fully characterized. Due to its structural similarity to thyroid hormones
thyroxine (T4) and triiodothyronine (T3), one possible mechanism of BPA toxicity is disruption of hormone transport by competitive
binding with the transport proteins. In this study, the binding interactions of BPA, T4, and T3 with three thyroid hormone transport
proteins, human serum albumin (HSA), transthyretin (TTR), and thyroxine-binding globulin (TBG) were investigated by fluorescence
measurement. Using two site-specific fluorescence probes dansylamide and dansyl-L-proline, the binding constants of BPA with HSA
at drug site I and site II were determined as 2.90 104 and 3.14 104 L/mol, respectively. By monitoring the intrinsic fluorescence
of tryptophan, a binding constant of 4.70 103 L/mol was obtained. Similarly, by employing 8-anilino-1-naphthalenesulfonic acid as
fluorescence probe, the binding a nity of BPA with TTR and TBG was measured to be 3.10 105 and 5.90 105 L/mol, respectively.
In general, BPA showed lower binding a nity with the proteins than T3 did, and even lower a nity than T4. Using these binding
constants, the amount of BPA which would bind to the transport proteins in human plasma was estimated. These results suggest that
the concentrations of BPA commonly found in human plasma are probably not high enough to interfere with T4 transport. 相似文献
996.
Potassium-modified ceria-zirconia catalyst was synthesized by wetness impregnation method.The ageing treatment was performed in static air at 800°C for 20 hr to evaluate the thermal stability of the catalyst.The catalysts were characterized by X-ray diffraction,BET surface area,oxygen storage capacity,NOx-temperature programmed desorption and soot-temperature programmed oxidation measurements.By introduction of potassium,the maximum soot oxidation rate temperature(Tm) of the ceria-zirconia based catalyst de... 相似文献
997.
Leaf litterfall plays an important role in transporting atmospheric mercury to soil in forests area. 相似文献
998.
999.
对广西区6个国有林场、2个集体林区速生桉人工林和3个育苗基地固体难降解物的使用现状进行调查,结果表明:调查林地一个轮伐期使用肥料包装袋总量为30 148.1 kg,折合每公顷林地平均每年使用量约为0.2 kg,两个轮伐期使用育苗容器总量为7 394.2 kg,每公顷林地平均每年使用量约为0.023 kg;育苗基地使用育苗容器每年1 725 kg,其中仅有525 kg塑料营养钵回收利用。为此建议提高林业工作者环保意识,把防止林用难降解物污染列入林业环境保护中,做好回收利用工作,并开发使用易降解的新型材料,防治林地"白色污染"。 相似文献
1000.