全文获取类型
收费全文 | 5261篇 |
免费 | 331篇 |
国内免费 | 2292篇 |
专业分类
安全科学 | 390篇 |
废物处理 | 321篇 |
环保管理 | 384篇 |
综合类 | 3154篇 |
基础理论 | 919篇 |
环境理论 | 2篇 |
污染及防治 | 2039篇 |
评价与监测 | 238篇 |
社会与环境 | 179篇 |
灾害及防治 | 258篇 |
出版年
2024年 | 17篇 |
2023年 | 112篇 |
2022年 | 275篇 |
2021年 | 263篇 |
2020年 | 222篇 |
2019年 | 191篇 |
2018年 | 219篇 |
2017年 | 272篇 |
2016年 | 304篇 |
2015年 | 380篇 |
2014年 | 422篇 |
2013年 | 578篇 |
2012年 | 458篇 |
2011年 | 438篇 |
2010年 | 383篇 |
2009年 | 354篇 |
2008年 | 353篇 |
2007年 | 300篇 |
2006年 | 282篇 |
2005年 | 195篇 |
2004年 | 143篇 |
2003年 | 183篇 |
2002年 | 184篇 |
2001年 | 153篇 |
2000年 | 148篇 |
1999年 | 148篇 |
1998年 | 153篇 |
1997年 | 116篇 |
1996年 | 113篇 |
1995年 | 121篇 |
1994年 | 105篇 |
1993年 | 70篇 |
1992年 | 65篇 |
1991年 | 46篇 |
1990年 | 41篇 |
1989年 | 24篇 |
1988年 | 12篇 |
1987年 | 10篇 |
1986年 | 13篇 |
1985年 | 7篇 |
1984年 | 3篇 |
1983年 | 5篇 |
1982年 | 3篇 |
排序方式: 共有7884条查询结果,搜索用时 0 毫秒
121.
122.
油田回注水中优势硫酸盐还原菌的分离鉴定与生理特性研究 总被引:2,自引:0,他引:2
从胜利油田回注水中筛选得到一株硫酸盐还原菌,命名为zsz1209。经过16SrDNA序列分析,鉴定zsz1209为梭菌属(Clostridium)。实验研究了zsz109的生理特性,并对通过调节环境pH来抑制菌株zsz1209生长繁殖的可行性进行了探讨。实验结果表明:菌株zsz1209的理想碳源为乙酸钠,在30~60℃之间可较好地生长;SOi浓度低至50mg/L时,生长未受到明显抑制。当培养环境pH高至8.5~9.0或低至3.5~4.0时,检测菌株zsz1209对SO4^2-和碳源(COD)的利用情况,发现zsz1209的生长受到明显抑制,结果表明利用改变环境pH来抑制微生物对油田的腐蚀具有可行性。 相似文献
123.
利用脱硫废碱液对酸化后的含铬废水进行处理,研究了废水初始pH、脱硫废碱液加入量和静置时间等对Cr(Ⅵ)转化率的影响.实验结果表明,在废水初始pH为1.4、静置时间为30 min的条件下,处理30 mL Cr(Ⅵ)质量浓度为126.5 mg/L的含铬废水,适宜的脱硫废碱液加入量为6 mL,此条件下Cr(Ⅵ)转化率接近10... 相似文献
124.
Yin Yuanyuan Li Tong Kuang Duyi Lu Yuanan Shen Yan Xu Jun Jiang Songhui Wang Xia 《Environmental science and pollution research international》2019,26(6):5485-5499
Environmental Science and Pollution Research - Nitrosamines (NAms) are potent genotoxic and carcinogenic but widely detected in drinking water. This study aimed to investigate the occurrence of... 相似文献
125.
Richao Cong Toru Matsumoto Wenchao Li He Xu Takamasa Hayashi Changjun Wang 《Journal of Material Cycles and Waste Management》2017,19(4):1423-1436
With the rapid economic development in China, the amount of plastic waste (PW) generated has greatly increased and much of the waste is currently not treated. To reduce greenhouse gas (GHG) emissions from recycling of PW, we estimated the PW flow and considered methods to improve the household PW recycling system in Tianjin by adjusting processes during transportation and establishing a PW recycling factory in Zi’ya Industrial Park. The goal of the study was to identify reasonable improvements for the recycling system and clarify the environmental load. Geographic information system (GIS) technology was used to simulate transport processes for comparing GHG emissions from the transport processes between the present case and an improved case. Life cycle assessment (LCA) was used to compare GHG emissions between a projected scenario and a baseline scenario. Estimated GHG emissions during transport processes in the improved case were reduced by about 12,197 t CO2 eq per year compared to the present case, equivalent to about 65.9 % of the total emissions in the present case. GHG emissions in the projected scenario were about 101,738 t CO2 eq less per year than the baseline scenario, equivalent to about 75.5 % of the total emissions in the baseline scenario. 相似文献
126.
表面活性剂对多壁碳纳米管吸附Pb~(2+)的影响 总被引:1,自引:0,他引:1
多壁碳纳米管(MWNT)在吸附有毒气体和重金属离子方面具有极高的应用价值.针对MWNT对水溶液中Pb2+的净化吸附进行了研究,从吸附量,吸附速率、动力学角度考察了表面活性剂、Pb2+浓度对MWNT吸附Pb2+的影响.结果表明,司班-60、吐温-20、阿拉伯树胶等表面活性剂的加入,促进了MWNT在溶液中的分散,导致在Pb2+摩尔浓度为3~18 mmol/L的Lang-muir和Freundlich等温吸附方程中的吸附常数(K)变大,使得MWNT对Pb2+的吸附速率和平衡吸附量都得到提高;随着溶液中Pb2+浓度的增大,MWNT对其吸附量渐至饱和,随后由于Pb2+的位阻作用.吸附量下降;在这3种表面活性剂中,由于司班-60具有相对较小的分子量,其分散的MWNT在Pb2+摩尔浓度为14 mmol/L时,吸附量最大,为230 mg/g. 相似文献
127.
城镇杂用再生水的水质安全评价关键指标探讨 总被引:2,自引:0,他引:2
污水再生利用是解决中国淡水资源短缺的有效途径,再生水的水质安全问题一直以来受到广泛关注.以城镇杂用再生水的水质安全为目标,从再生水中残留的化学污染物和病原微生物出发,通过全面分析污染物在回用过程中危害人体健康和生态环境的可能途径,结合当前国内外城镇杂用水的水质标准,提出了包括综合毒性指标、生物学指标、可吸附有机卤化物指标、挥发性有机物指标等在内的城镇杂用再生水水质安全评价关键指标. 相似文献
128.
Yu Ren Aijun Ding Tao Wang Xinhua Shen Jia Guo Jiamin Zhang Yan Wang Pengju Xu Xinfeng Wang Jian Gao Jeffrey L. Collett 《Atmospheric environment (Oxford, England : 1994)》2009,43(9):1702-1711
Measurement of ambient gas-phase total peroxides was performed at the summit of Mount Tai (Mt. Tai, 1534 m above sea level) in central-eastern China during March 22–April 24 and June 16–July 20, 2007. The hourly averaged concentration of peroxides was 0.17 ppbv (± 0.16 ppbv, maximum: 1.28 ppbv) and 0.55 ppbv (± 0.67 ppbv, maximum: 3.55 ppbv) in the spring and summer campaigns, respectively. The average concentration of peroxides at Mt. Tai, which is in a heavily polluted region, was much lower than hydrogen peroxide measurements made at some rural mountain sites, suggesting that significant removal processes took place in this region. An examination of diurnal variation and a correlation analysis suggest that these removal processes could include chemical suppression of peroxide production due to the scavenging of peroxy and hydroxy radicals by high NOx, wet removal by clouds/fogs rich in dissolved sulfur dioxide which reacts quickly with peroxides, and photolysis. These sinks competed with photochemical sources of peroxides, resulting in different mean concentrations and diurnal pattern of peroxides in the spring and summer. A principal component analysis was conducted to quantify the major processes that influenced the variation of peroxide concentrations. This analysis shows that in the spring photochemical production was an important source of peroxides, and the major sink was scavenging during upslope transport of polluted and humid air from the lower part of the planetary boundary layer (PBL) and wet removal by synoptic scale clouds. During the summer, highly polluted PBL air (with high NOx) was often associated with very low peroxides due to the chemical suppression of HO2 by high NOx and wet-removal by clouds/fogs in this sulfur-rich atmosphere, especially during the daytime. Higher concentrations of peroxides, which often appeared at mid-nighttime, were mainly associated with subsidence of air masses containing relatively lower concentrations of NOy. 相似文献
129.
采用电称冲击低压系统(ELPI)将无烟室和吸烟室内的空气颗粒物(0.03~10.00 μm)分成12级,对其粒子数和质量浓度进行测定.结果表明,吸烟室PM0.03~10.00的日平均粒子数和质量浓度分别是无烟室的1.50、1.13倍.烟草烟雾对室内颗粒物粒子数的影响集中在0.03~1.00 μm粒径段;对室内颗粒物质量浓度的影响表现为双模态结构,峰值分别在0.20~0.70、5.00~8.20 μm粒径段.烟草烟雾颗粒物的粒子数和质量浓度随烟雾消散时间的增加而减少,粒径越小,减小的越明显;烟草烟雾颗粒物在室内消散缓慢,会在长时间内造成影响,应引起足够关注. 相似文献
130.
Juan G. Navea Shihe Xu Charles O. Stanier Mark A. Young Vicki H. Grassian 《Atmospheric environment (Oxford, England : 1994)》2009,43(26):4060-4069
We have carried out kinetic studies to characterize the heterogeneous decay of octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5) in the presence of representative mineral dust aerosol in order to obtain a better understanding of the atmospheric fate of these siloxanes. The heterogeneous chemistry of D4 and D5 with various mineral dusts was studied in an environmental aerosol reaction chamber using FTIR absorption spectroscopy to monitor the reaction. The apparent heterogeneous uptake coefficient, γapp, for D4 and D5 with various mineral dusts was measured under dry conditions and as a function of relative humidity (RH). In addition, the effect of initial D4 and D5 concentration on the rate and yield of the reaction was examined. The uptake coefficient, γapp, for D4 and D5 was similar for the most reactive aerosols tested, with kaolinite ≈hematite > silica. Limited uptake onto carbon black and calcite surfaces was observed for either siloxane. Reaction with hematite and kaolinite resulted in multilayer coverages, suggesting extensive polymerization of D4 and D5 on the aerosol surface. 相似文献