全文获取类型
收费全文 | 10094篇 |
免费 | 887篇 |
国内免费 | 2329篇 |
专业分类
安全科学 | 553篇 |
废物处理 | 195篇 |
环保管理 | 2019篇 |
综合类 | 6961篇 |
基础理论 | 1176篇 |
环境理论 | 7篇 |
污染及防治 | 751篇 |
评价与监测 | 1093篇 |
社会与环境 | 451篇 |
灾害及防治 | 104篇 |
出版年
2024年 | 45篇 |
2023年 | 207篇 |
2022年 | 317篇 |
2021年 | 414篇 |
2020年 | 425篇 |
2019年 | 341篇 |
2018年 | 288篇 |
2017年 | 395篇 |
2016年 | 406篇 |
2015年 | 494篇 |
2014年 | 525篇 |
2013年 | 714篇 |
2012年 | 693篇 |
2011年 | 764篇 |
2010年 | 611篇 |
2009年 | 588篇 |
2008年 | 497篇 |
2007年 | 694篇 |
2006年 | 689篇 |
2005年 | 501篇 |
2004年 | 479篇 |
2003年 | 492篇 |
2002年 | 424篇 |
2001年 | 381篇 |
2000年 | 376篇 |
1999年 | 273篇 |
1998年 | 205篇 |
1997年 | 181篇 |
1996年 | 157篇 |
1995年 | 113篇 |
1994年 | 114篇 |
1993年 | 87篇 |
1992年 | 74篇 |
1991年 | 61篇 |
1990年 | 42篇 |
1989年 | 22篇 |
1988年 | 16篇 |
1987年 | 32篇 |
1986年 | 18篇 |
1985年 | 12篇 |
1982年 | 16篇 |
1981年 | 18篇 |
1980年 | 13篇 |
1979年 | 11篇 |
1978年 | 16篇 |
1977年 | 6篇 |
1974年 | 7篇 |
1973年 | 10篇 |
1972年 | 8篇 |
1971年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 562 毫秒
91.
The present work attempts statistical analysis of groundwater quality near a Landfill site in Nagpur, India. The objective
of the present work is to figure out the impact of different factors on the quality of groundwater in the study area. Statistical
analysis of the data has been attempted by applying Factor Analysis concept. The analysis brings out the effect of five different
factors governing the groundwater quality in the study area. Based on the contribution of the different parameters present
in the extracted factors, the latter are linked to the geological setting, the leaching from the host rock, leachate of heavy
metals from the landfill as well as the bacterial contamination from landfill site and other anthropogenic activities. The
analysis brings out the vulnerability of the unconfined aquifer to contamination. 相似文献
92.
Bhanarkar AD Srivastava A Joseph AE Kumar R 《Environmental monitoring and assessment》2005,109(1-3):73-80
Air pollution in the workplace environment due to industrial operation have been found to cause serious occupational health
hazard. Similarly, heat stress is still most neglected occupational hazard in the tropical and subtropical countries like
India. The hot climate augments the heat exposure close to sources like furnaces. In this study an attempt is made to assess
air pollution and heat exposure levels to workers in the workplace environment in glass manufacturing unit located in the
State of Gujarat, India. Samples for workplace air quality were collected for SPM, SO2, NO2 and CO2 at eight locations. Results of workplace air quality showed 8-hourly average concentrations of SPM: 165–9118 μg/m3, SO2: 6–9 μg/m3 and NO2: 5–42 μg/m3, which were below the threshold limit values of workplace environment. The level of CO2 in workplace air of the plant was found to be in the range 827–2886 μg/m3, which was below TLV but much higher than the normal concentration for CO2 in the air (585 mg/m3). Indoor heat exposure was studied near the furnace and at various locations in an industrial complex for glass manufacturing.
The heat exposure parameters including the air temperature, the wet bulb temperature, and the globe parameters were measured.
The Wet Bulb Globe Temperature (WBGT), an indicator of heat, exceeded ACGIH TLVs limits most of the time at all the locations
in workplace areas. The recommended duration of work and rest have also been estimated. 相似文献
93.
94.
95.
96.
97.
空气细颗粒物(PM2.5)污染特征及其毒性机制的研究进展 总被引:14,自引:2,他引:14
细颗粒物(PM2.5)是指空气动力学直径≤2.5μm的颗粒物,其表面吸附大量的有毒有害物质,并可通过呼吸沉积在肺泡,甚至可通过肺换气到达其他器官.由于细颗粒物的重要性,美国EPA已经于1997年颁布了细颗粒物的空气质量标准,年均值为0.015mg/m3,日均值为0.065mg/m3,然而我国至今仍未制定细颗粒物空气质量标准.颗粒物上吸附的化学组分主要可分成自然来源及燃煤或燃油等人为污染来源两大类,特别是来自工业性和居住区燃煤及汽车燃油尾气.空气细颗粒物污染表现为形态各异、成分复杂等特征.细颗粒物有明显的毒性作用,可引起机体呼吸系统、免疫系统等较为广泛的损害.细颗粒物与心肺疾病密切相关,如增加入院率、急诊次数、呼吸疾病及症状增加、肺功能下降,甚至于过早死亡.简要概述了细颗粒物的污染特征及其毒性机制研究进展. 相似文献
98.
99.
亚铵法制浆造纸厂中段废水处理技术分析研究 总被引:1,自引:0,他引:1
通过对采用两级气浮做预处理 ,生物硫化床串联接触氧化做深度处理的治理技术的分析研究 ,结合废水处理工程实例 ,说明了用两级串联气浮 +硫化床 +接触氧化工艺处理造纸中段水技术切实可靠 ,该治理工艺对处理亚铵法麦草制浆造纸中段废水有较强的针对性和可行性。 相似文献
100.
Biomonitoring dissolved heavy metals within estuaries,particularly at their upper reaches, frequently has to relyon several biomonitors; rarely a single species thrives allalong the salinity gradient. To properly do so, it must beestablished whether those biomonitors actually accumulateheavy metals alike. In this study, two brown seaweeds fromthe upper section of three NW Spain estuaries – the widely-known Fucus vesiculosus and the estuarine Fucusceranoides – were compared as metal biomonitors. Bothspecies were collected at five locations where they eithercoexist or live close to each other and their heavy metalcontent (Cu, Cr, Mn, Zn, Fe, Al) was measured. Analyseswere appropriately replicated for each species x locationcombination to allow a statistically reliable detection ofdifferences in bioaccumulation, with particular emphasis onthe magnitude of interspecific differences. The lack of significant differences for Cu, Mn, and Zncontents in F. ceranoides and F. vesiculosussupports the feasibility of their joint use to monitorthese metals along the estuaries. Conversely, F.ceranoides concentrated significantly higher levels of Cr,Fe, and Al than F. vesiculosus and hence combiningdata for both fucoids to monitor these elements seemsimpractical. The correlation of species differencestogether with a similar Al:Fe ratio in both weed tissue andsediment suggest that Cr, Fe, and Al tissue-burdens mightbe considerably biased by sediment retained on the surfaceof the weed. Parallel analyses of Al and/or Fe in seaweedsand sediments could serve to keep track of thisinterference and may help to combine data from both fucoidsfor monitoring elements like Cr. 相似文献