全文获取类型
收费全文 | 1253篇 |
免费 | 94篇 |
国内免费 | 233篇 |
专业分类
安全科学 | 62篇 |
废物处理 | 4篇 |
环保管理 | 183篇 |
综合类 | 765篇 |
基础理论 | 177篇 |
环境理论 | 1篇 |
污染及防治 | 25篇 |
评价与监测 | 91篇 |
社会与环境 | 185篇 |
灾害及防治 | 87篇 |
出版年
2024年 | 7篇 |
2023年 | 21篇 |
2022年 | 45篇 |
2021年 | 49篇 |
2020年 | 40篇 |
2019年 | 52篇 |
2018年 | 52篇 |
2017年 | 49篇 |
2016年 | 43篇 |
2015年 | 62篇 |
2014年 | 51篇 |
2013年 | 71篇 |
2012年 | 79篇 |
2011年 | 84篇 |
2010年 | 82篇 |
2009年 | 71篇 |
2008年 | 60篇 |
2007年 | 71篇 |
2006年 | 75篇 |
2005年 | 50篇 |
2004年 | 65篇 |
2003年 | 70篇 |
2002年 | 51篇 |
2001年 | 40篇 |
2000年 | 38篇 |
1999年 | 19篇 |
1998年 | 25篇 |
1997年 | 28篇 |
1996年 | 37篇 |
1995年 | 9篇 |
1994年 | 15篇 |
1993年 | 19篇 |
1992年 | 9篇 |
1991年 | 11篇 |
1990年 | 12篇 |
1989年 | 4篇 |
1988年 | 6篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1977年 | 1篇 |
1972年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有1580条查询结果,搜索用时 15 毫秒
91.
Andrés Pérez-parada Joaquín González Lucía Pareja Lucía Geis-Asteggiante Marcos Colazzo Silvina Niell 《Journal of environmental science and health. Part. B》2013,48(8):796-803
In order to evaluate the extraction of pesticide residues that are transferred to the brew during mate drinking process of P.U.1 yerba mate leaves (Ilex paraguariensis), a special device to simulate the way in which mate is drunk in Uruguay was developed. The transfer to the brew of 12 organophosphates, 5 synthethic pyrethroids and one organochlorine pesticide from spiked samples was studied. The relationship between the transfer data thus obtained and physicochemical properties like water solubility (Ws), octanol-water coefficient (Kow) and Henry's constant (H) was evaluated. The extractability of the pesticide residues from yerba mate can be correlated with log Ws and log Kow. These transfer values allowed the calculation of ARLs (acceptable residue level) for the pesticides following Food and Agriculture Organization (FAO), World Health Organizaion (WHO) guidelines. These results can help the future establishment of maximum residue levels (MRLs) 相似文献
92.
93.
Domestic water conservation in arid climates can result in efficient utilization of existing water supplies. The impacts of
conservation measures such as the installation of water-saving devices, water metering and pricing schemes, water rationing
and public awareness programs, strict plumbing codes, penalties for wasting water, programs designed to reduce leakage from
public water lines and within the home, water-efficient landscaping, economic and ethical incentives are addressed in detail.
Cost savings in arid climates, with particular reference to Saudi Arabia, in relation to some conservation techniques, are
presented. Water conservation technology and tentative demonstration and implementation of water conservation programs are
discussed. 相似文献
94.
高黎贡山自然保护区位于怒江水系和伊洛瓦底江水系之间。据调查,共有鱼类47种。鱼类组成特点:北部多为中亚高山区种类,属华西区;南部以南亚类群占优势,属华南区。 相似文献
95.
陕西关中地区城市灾害评价 总被引:8,自引:2,他引:8
本文在详细分析关中地区六个大中城市的主要自然灾害和城市地质灾害的基础上,分别评价了各种灾害造成的经济损失,各个城市的灾害危险性、易损性和抗灾能力,并结合防灾对策对城市进行了综合分类。 相似文献
96.
ABSTRACT: Although evidence of modern recharge in the North African and Arabian sedimentary basin aquifers exists, it is difficult to determine the volume of recharge. Also, from the evidence of regional groundwater gradients, the flow within the aquifers seems to be appreciably greater than one would intuitively expect. A hypotehtical model embodying the characteristics of the aquifers has been used to investigate the likely significance of various possible flow mechanisms. It is shown that while dewatering in the unconfined area can possibly contribute to flows for a considerable period of time, the maintenance of water levels in the unconfined zone must be the result of modern recharge. It is also shown that recharge depths of less than 10 mm per annum are sufficient given suitable aquifer parameters. Results for various combinations of aquifer parameters and configurations are given, including layered aquifers and the effects of restricted oufflows. Comparisons are made using a “bench mark” example. The work indicates that there is little point in carrying out conventional hydrological balance studies in hyper-arid areas and that, instead, more emphasis should be placed upon good groundwater hydrographic data and modeling. 相似文献
97.
西南地区1959—1961年三年自然灾害分析 总被引:1,自引:1,他引:1
该文以丰富而翔实的资料就西南地区1959~1961年三年自然灾害,特别是旱灾的灾情、灾情特点、灾害损失、灾害原因及其经验教训进行了论述. 相似文献
98.
应用两种描述地震活动平静的特征参数Wq 和σH 对华东地区 1972年以来ML≥ 2 .3地震进行时空扫描。结果表明 :Wq 在华东地区大多数M >5地震之前均出现 1年左右或稍长时间的平静异常 ,震中一般在平静异常区的边缘或内部。对Wq 空间异常区σH 的时间扫描在某些地区也能够较好地显示1年左右的平静异常。这可能说明了地震活动平静也是中强地震的一种中短期预报指标 相似文献
99.
100.