全文获取类型
收费全文 | 1107篇 |
免费 | 60篇 |
国内免费 | 357篇 |
专业分类
安全科学 | 100篇 |
废物处理 | 71篇 |
环保管理 | 85篇 |
综合类 | 625篇 |
基础理论 | 190篇 |
污染及防治 | 334篇 |
评价与监测 | 36篇 |
社会与环境 | 38篇 |
灾害及防治 | 45篇 |
出版年
2024年 | 1篇 |
2023年 | 19篇 |
2022年 | 53篇 |
2021年 | 51篇 |
2020年 | 42篇 |
2019年 | 31篇 |
2018年 | 44篇 |
2017年 | 47篇 |
2016年 | 49篇 |
2015年 | 68篇 |
2014年 | 89篇 |
2013年 | 106篇 |
2012年 | 88篇 |
2011年 | 124篇 |
2010年 | 76篇 |
2009年 | 71篇 |
2008年 | 56篇 |
2007年 | 56篇 |
2006年 | 46篇 |
2005年 | 49篇 |
2004年 | 37篇 |
2003年 | 45篇 |
2002年 | 33篇 |
2001年 | 30篇 |
2000年 | 33篇 |
1999年 | 37篇 |
1998年 | 30篇 |
1997年 | 22篇 |
1996年 | 13篇 |
1995年 | 22篇 |
1994年 | 18篇 |
1993年 | 15篇 |
1992年 | 5篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 4篇 |
1988年 | 2篇 |
1987年 | 4篇 |
排序方式: 共有1524条查询结果,搜索用时 265 毫秒
331.
Liu SL Luo YM Cao ZH Wu LH Ding KQ Christie P 《Environmental geochemistry and health》2004,26(2-3):285-293
Mycorrhizal and non-mycorrhizal alfalfa (Medicago sativa) was grown in pots containing soil artificially contaminated with various levels of benzo[a]pyrene (B[a]P) (0, 1, 10 and 100 mg kg(-1)). Soil and plants were sampled after 30, 40, 50, 60 and 90 days and compared with unlanted pots. The percentage of mycorrhizal root length colonized by Glomus caledoniun was not significantly affected by the addition of B[a]P up to 10 mg kg(-1) but was significantly lower at 100 mg kg(-1)B[a]P compared with low concentrations (p < 0.05). There was no difference in soil polyphenol oxidase and dehydrogenase activity among the controls and applications of 1 and 10 mg kg(-1) of B[a]P. However, enzyme activities were significantly higher at 100 mg kg(-1) B[a]P compared with the other three treatments, and there was no mycorrhizal effect. Over a period of 90 days the concentration of B[a]P in soil in which alfalfa was grown was significantly lower than in unplanted soil (p < 0.05). Degradation rates of B[a]P added at 1, 10 and 100 mg kg(-1) without G. caledonium were 76, 78 and 53%, and with mycorrhizal inoculation were 86, 87 and 57%. The degradation rate in unplanted soil was significantly lower than in planted soil, and was significantly higher in medium- and low-B[a]P treatments than in the high B[a]P concentration tested. There is a possibility of enhancement phytoremediation of PAHs in rhizosphere soil with arbuscular mycorrhizal fungi. 相似文献
332.
S.L. Liu Y.M. Luo Z.H. Cao L.H. Wu K.Q. Ding P. Christie 《Environmental geochemistry and health》2004,26(2):285-293
Mycorrhizal and non-mycorrhizal alfalfa (Medicago sativa) was grown in pots containing soil artificially contaminated with various levels of benzo[a]pyrene (B[a]P)(0, 1, 10 and 100 mg kg–1). Soil and plants were sampled after 30, 40, 50, 60 and 90 days and compared with unlanted pots. The percentage of mycorrhizal root length colonized by Glomus caledoniun was not significantly affected by the addition of B[a]P up to 10 mg kg–1 but was significantly lower at 100 mg kg–1B[a]P compared with low concentrations (p < 0.05). There was no difference in soil polyphenol oxidase and dehydrogenase activity among the controls and applications of 1 and 10 mg kg–1 of B[a]P. However, enzyme activities were significantly higher at 100 mg kg–1B[a]P compared with the other three treatments, and there was no mycorrhizal effect. Over a period of 90 days the concentration of B[a]P in soil in which alfalfa was grown was significantly lower than in unplanted soil (p < 0.05). Degradation rates of B[a]P added at 1, 10 and 100 mg kg–1 without G. caledonium were 76, 78 and 53%, and with mycorrhizal inoculation were 86, 87 and 57%. The degradation rate in unplanted soil was significantly lower than in planted soil, and was significantly higher in medium- and low-B[a]P treatments than in the high B[a]P concentration tested. There is a possibility of enhancement phytoremediation of PAHs in rhizosphere soil with arbuscular mycorrhizal fungi. 相似文献
333.
以花岗岩母质发育的旱地红壤和水稻土为研究对象,探讨了不同耕作制度下土壤中锰的赋存形态及其生物有效性。结果表明:在水旱轮作条件下,土壤中的锰更多地以代换态和晶形铁结合态存在;旱作土壤中的锰则较多地以有机态和无定形铁结合态存在.然而,单位有机质络合的锰量却是水稻土大于红壤。水旱轮作措施具有活化锰的作用,使得土壤中锰有效性更大并且主要以代换态存在。旱作土壤则不同,土壤活性锰除来自代换衣外,尚有大约45%以有机态或无定形铁结合态存在。 相似文献
334.
335.
336.
337.
338.
尾矿利用是矿业环境治理和经济增长的新途径 总被引:2,自引:0,他引:2
本文阐述了尾矿的合理开发利用是21世纪矿业治理环境污染和经济增长的新途径,以及尾矿综合利用研究技术路线和研究内容。 相似文献
339.
目的 解决压缩机组一级进气缓冲罐连接螺栓断裂及管嘴失效问题.方法 针对压缩机机械结构和生产工况,通过气流脉动、机械振动测试分析,并结合仿真分析,提出气流脉动抑制措施和机械振动控制措施.分析得出一级进气缓冲罐连接螺栓断裂及管嘴失效的主要原因.结果 压缩机组中体支撑结构刚度不够,缸内交变气流力作用引起进气缓冲罐和气缸水平方向振动.原机组气流脉动控制设计不合适,导致一级进气缓冲罐内脉动不平衡力偏大.结论 提出了基于气流脉动控制和机械振动控制的整改方案,并进行了初步实施,实现了管嘴法兰螺栓受力状态的优化,降低了振动强度,达到了治理目的. 相似文献
340.
饮用水消毒过程中卤代烃的形成和控制 总被引:4,自引:0,他引:4
研究了饮用水消毒过程中卤代烃形成的各种条件及控制技术。结果表明:加氯量多时卤代烃形成多、水温高时卤代烃生成快、加凝聚剂后因pH值下降能控制卤代烃形成、加氨氮后生成氯胺可进一步降低饮用水中的卤代烃。 相似文献