全文获取类型
收费全文 | 2936篇 |
免费 | 304篇 |
国内免费 | 983篇 |
专业分类
安全科学 | 355篇 |
废物处理 | 113篇 |
环保管理 | 253篇 |
综合类 | 1916篇 |
基础理论 | 422篇 |
污染及防治 | 665篇 |
评价与监测 | 191篇 |
社会与环境 | 132篇 |
灾害及防治 | 176篇 |
出版年
2024年 | 10篇 |
2023年 | 48篇 |
2022年 | 142篇 |
2021年 | 181篇 |
2020年 | 136篇 |
2019年 | 115篇 |
2018年 | 117篇 |
2017年 | 150篇 |
2016年 | 152篇 |
2015年 | 217篇 |
2014年 | 235篇 |
2013年 | 255篇 |
2012年 | 268篇 |
2011年 | 267篇 |
2010年 | 236篇 |
2009年 | 183篇 |
2008年 | 211篇 |
2007年 | 190篇 |
2006年 | 181篇 |
2005年 | 131篇 |
2004年 | 98篇 |
2003年 | 84篇 |
2002年 | 91篇 |
2001年 | 97篇 |
2000年 | 78篇 |
1999年 | 69篇 |
1998年 | 64篇 |
1997年 | 59篇 |
1996年 | 37篇 |
1995年 | 30篇 |
1994年 | 30篇 |
1993年 | 20篇 |
1992年 | 17篇 |
1991年 | 4篇 |
1990年 | 5篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
排序方式: 共有4223条查询结果,搜索用时 15 毫秒
991.
广东某市部分中学生尿液中多种多环芳烃单羟基代谢物暴露水平分析 总被引:2,自引:0,他引:2
为了解地处多环芳烃(PAHs)排放源附近的背景人群体内的PAHs暴露水平,于2006年11月采集广东某市某钢铁公司焦化厂附近一中学部分学生(14~18岁)尿样,采用高效液相色谱-荧光检测法,在检测尿液中PAHs单羟基代谢物(HO-PAHs)的基础上,对受试人群体内的PAHs暴露水平,1-羟基芘(1-HOP)与其他HO-PAHs的相关性进行了分析.结果表明,尿样中共检测出7种HO-PAHs,除4-羟基菲(4-HOPhe)外,其余HO-PAHs的检出率均为100%.检出的2-羟基萘(2-HON)、2-羟基芴(2-HOFlu)、2-+3-羟基菲(2-+3-HOPhe,由于2-羟基菲(2-HOPhe)和3-羟基菲(3-HOPhe)属共溢出峰,因此以2-+3-HOPhe表示)、9-羟基菲(9-HOPhe)、4-HOPhe和1-HOP的浓度中位数分别为5.34、4.09、0.08、0.80、0.03、0.35 μmol/mol(以尿肌酐计).受试人群尿液中2-HON、2-HOFlu、总HOPhe浓度(简称∑HOPhe)和1-HOP的浓度中位数高于南方沿海某市中学生,1-HOP浓度的中位数也高于国内类似背景人群.1-HOP浓度与其他HO-PAHs浓度的相关性并不好(相关系数为0.213~0.653),且与2-HON、9-HOPhe和检出的∑HOPhe浓度的相关性均不显著,显示多种HO-PAHs的联合测定可能更能客观评价人体内的PAHs暴露水平. 相似文献
992.
Xiao-Huan Liu Yang Zhang Shu-Hui Cheng Jia Xing Qiang Zhang David G. Streets Carey Jang Wen-Xing Wang Ji-Ming Hao 《Atmospheric environment (Oxford, England : 1994)》2010,44(20):2415-2426
The U.S. EPA Models-3 Community Multiscale Air Quality (CMAQ) modeling system with the process analysis tool is applied to China to study the seasonal variations and formation mechanisms of major air pollutants. Simulations show distinct seasonal variations, with higher surface concentrations of sulfur dioxide (SO2), nitrogen dioxide (NO2), and particulate matter with aerodynamic diameter less than or equal to 10 μm (PM10), column mass of carbon monoxide (CO) and NO2, and aerosol optical depth (AOD) in winter and fall than other seasons, and higher 1-h O3 and troposphere ozone residual (TOR) in spring and summer than other seasons. Higher concentrations of most species occur over the eastern China, where the air pollutant emissions are the highest in China. Compared with surface observations, the simulated SO2, NO2, and PM10 concentrations are underpredicted throughout the year with NMBs of up to ?51.8%, ?32.0%, and ?54.2%, respectively. Such large discrepancies can be attributed to the uncertainties in emissions, simulated meteorology, and deviation of observations based on air pollution index. Max. 1-h O3 concentrations in Jan. and Jul. at 36-km are overpredicted with NMBs of 12.0% and 19.3% and agree well in Apr. and Oct. Simulated column variables can capture the high concentrations over the eastern China and low values in the central and western China. Underpredictions occur over the northeastern China for column CO in Apr., TOR in Jul., and AODs in both Apr. and Jul.; and overpredictions occur over the eastern China for column CO in Oct., NO2 in Jan. and Oct., and AODs in Jan. and Oct. The simulations at 12-km show a finer structure in simulated concentrations than that at 36-km over higher polluted areas, but do not always give better performance than 36-km. Surface concentrations are more sensitive to grid resolution than column variables except for column NO2, with higher sensitivity over mountain and coastal areas than other regions. 相似文献
993.
土地利用/覆被变化是生态环境演变最重要的因素之一,其研究对于促进区域生态经济协调发展有重要意义。根据1976年和2006年玛纳斯河流域两期遥感影像资料,基于生态经济学的最新方法采用卫星遥感技术以及Costanza等的生态系统服务价值评价手段,对期间玛纳斯河流域生态服务系统服务功能价值变化进行分析研究。结果表明:①玛纳斯流域土地利用结构变化在30年间表现为草地、林地、不断减少,而耕地、水域、沙地和建设用地不断增加,反映出人类因素及生态环境恶化的趋势;②该流域生态系统服务功能价值总额由1976年123.831 08元减少至2006年101.521 08元。减幅:18.02%,年均减少0.741 08元,通过对玛纳斯河流域生态系统服务功能价值进行评价,为玛纳斯河流域生态开发和治理,以及环境整治提供决策依据。 相似文献
994.
995.
996.
997.
Lin Zhou Gui Fu Yujingyang Xue 《International journal of occupational safety and ergonomics》2018,24(3):329-340
Human and organizational factors have been proven to be the prime causes of Chinese hazardous chemical accidents (HCAs). A modified version of the Human Factors Analysis and Classification System (HFACS), namely the HFACS-Hazardous Chemicals (HC), was developed to identify the human factors involved in Chinese HCAs. The ‘8.12’ Tianjin Port fire and explosion, the costliest HCA in recent years, was reanalyzed using this framework, and the results were compared with the official accident inquiry report to determine their differences related to the identification of human and organizational factors. The study revealed that interacting human factors from different levels in Ruihai Company led to this catastrophe, and the inquiry report had limitations in the identification of human factors and the guidance for similar accident prevention. This study showed the applicability of the HFACS-HC in HCA analyses as well as the necessity to recommend this approach for future HCA investigations. 相似文献
998.
Song Cui Qiang Fu Yi-Fan Li Wen-long Li Tian-xiao Li Min Wang Zhen-xiang Xing Lu-ji Zhang 《Environmental science and pollution research international》2016,23(16):15952-15962
This study investigated the contamination levels, homologue, and congener profiles and evaluated the residue inventory of polychlorinated biphenyls (PCBs) in sediment of the Songhua River in the vicinity of cement plant. The total concentration of detected 35 PCB congeners ranged from 1.12 to 2.19 ng/g dry weight (dw) in sediment, with a mean value of 1.56 ng/g dw, and the concentration of PCBs decreased in the following order: the downstream?>?cement plant?>?upstream. The results of total organic carbon (TOC)-normalized PCB concentrations indicate that the sediments have low potential ecological risk in this area. The study results on homologue and congener of PCBs show that the emissions from cement production could be the major sources of PCBs in sediment, and the low-chlorinated PCBs will be exchanged among air, water, and sediment with increasing temperature during summer and flow to downstream with water during the wet season. The spatial density and total burden of PCBs in the surface sediments were 17.2 ng/cm2 and 1.2 kg, respectively. To our knowledge, this study is the first to explore the pollution characteristics of unintentionally produced PCB emissions from cement industry by means of monitoring sediment samples. 相似文献
999.
研究了亚铁盐中NO3-、SO42-、Cl-、Br-等阴离子对Fenton氧化降解高浓度聚乙烯醇(PVA)效果的影响。实验结果表明:酸性条件下具有氧化性的阴离子NO3-或能被氧化形成具有氧化性物质的离子Cl-、Br-对Fenton氧化降解PVA有协同促进作用,且氧化性越强越容易促使PVA大分子链断裂;含NO3-、Cl-、Br-和SO42-的Fenton氧化降解PVA,COD去除率分别为70.05%、70.60%、72.40%和87.90%。采用COD去除率相差不大、产物分子量较小的硝酸亚铁、氯化亚铁、溴化亚铁中的一种作为Fenton试剂催化降解PVA较适宜。 相似文献
1000.
Environmental Science and Pollution Research - As the largest developing country in the world, China has witnessed fast-paced urbanization over the past three decades with rapid economic growth. In... 相似文献