全文获取类型
收费全文 | 3393篇 |
免费 | 231篇 |
国内免费 | 1260篇 |
专业分类
安全科学 | 242篇 |
废物处理 | 210篇 |
环保管理 | 250篇 |
综合类 | 1984篇 |
基础理论 | 578篇 |
环境理论 | 2篇 |
污染及防治 | 1143篇 |
评价与监测 | 159篇 |
社会与环境 | 171篇 |
灾害及防治 | 145篇 |
出版年
2024年 | 12篇 |
2023年 | 79篇 |
2022年 | 189篇 |
2021年 | 195篇 |
2020年 | 155篇 |
2019年 | 98篇 |
2018年 | 159篇 |
2017年 | 171篇 |
2016年 | 217篇 |
2015年 | 219篇 |
2014年 | 298篇 |
2013年 | 338篇 |
2012年 | 289篇 |
2011年 | 302篇 |
2010年 | 207篇 |
2009年 | 210篇 |
2008年 | 241篇 |
2007年 | 159篇 |
2006年 | 186篇 |
2005年 | 148篇 |
2004年 | 89篇 |
2003年 | 111篇 |
2002年 | 81篇 |
2001年 | 85篇 |
2000年 | 102篇 |
1999年 | 86篇 |
1998年 | 87篇 |
1997年 | 76篇 |
1996年 | 72篇 |
1995年 | 57篇 |
1994年 | 44篇 |
1993年 | 32篇 |
1992年 | 43篇 |
1991年 | 13篇 |
1990年 | 8篇 |
1989年 | 6篇 |
1988年 | 8篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1966年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有4884条查询结果,搜索用时 109 毫秒
291.
292.
南京大气细粒子中重金属污染特征及来源解析 总被引:2,自引:0,他引:2
利用2011年1月、4月、7月和10月在南京市区和北郊采集的气溶胶样品,研究了南京大气细粒子中zn、Ph、Hg、As和cd5种重金属的污染水平,通过元素相关性分析和因子分析方法,对细粒子中这些重金属的污染来源进行了初步解析。结果表明,南京大气细粒子及其重金属污染严重,北郊普遍比市区严重;As严重超标,cd在南京北郊超标约5倍,zn在市区与北郊的质量浓度均高于其他重金属元素。每种重金属的浓度均随季节而变化。市区细粒子中,As和zn可能主要与燃煤、轮胎灰尘和建筑扬尘等有关,Pb、Hg和cd主要来自交通尘、城市垃圾焚烧等。北郊细粒子中,As、Hg和zn主要来源于燃煤、钢铁冶炼等工业,Pb和cd主要与农作物秸秆燃烧、汽车尾气、道路扬尘等影响有关。 相似文献
293.
294.
Two industrial sites were investigated based on years of available hydrogeologic information and monitoring data for soil and groundwater. Collected data were forensically evaluated using age-dating and fingerprinting methods. The previous business uses of the project sites were as a gas station, laundry/dry-cleaning service, and car wash with petroleum underground storage tanks (USTs). As a result, these sites were exposed to a number of toxic contaminants at relatively high concentrations. Source control was necessary for successful remediation and the ultimate removal of the remaining compounds from these industrial sites. Although contaminated soil around the source was excavated during the remedial action and the high concentrations of contaminants were reduced, typical groundwater contaminants such as petroleum hydrocarbons as gasoline (TPH-G), benzene, toluene, ethylbenzene, xylenes (BTEX), and oxygenates including methyl tert-butyl ether (MTBE), diisopropyl ether (DIPE), ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME), and tert-butyl alcohol (TBA) were persistently found at the studied sites around the source points. The plume and concentration of contaminants had changed their shapes and strength for all monitoring periods. Thus, additional source control seems to be a requirement for the complete removal of source contamination, which must be ascertained with groundwater and soil monitoring on a regular time base. For the study sites, monitored natural attenuation was relatively feasible for the long-term plan; however, it did not offer a perfect remediation solution for an ultimate goal because of residual toxic compounds that might have affected the surrounding residential areas at higher concentrations than their health limits. Therefore, as a remediation strategy, the combination of clean-up technology and natural attenuation with monitoring activities are more highly recommended than either clean-up or natural attenuation used separately. 相似文献
295.
Maria Lourdes P. Dalida Kristine Marfe S. Amer Chia-Chi Su Ming-Chun Lu 《Environmental science and pollution research international》2014,21(2):1208-1216
This study investigated the photocatalytic degradation of acetaminophen (ACT) in synthetic titanium dioxide (TiO2) solution under a visible light (λ >440 nm). The TiO2 photocatalyst used in this study was synthesized via sol–gel method and doped with potassium aluminum sulfate (KAl(SO4)2) and sodium aluminate (NaAlO2). The influence of some parameters on the degradation of acetaminophen was examined, such as initial pH, photocatalyst dosage, and initial ACT concentration. The optimal operational conditions were also determined. Results showed that synthetic TiO2 catalysts presented mainly as anatase phase and no rutile phase was observed. The results of photocatalytic degradation showed that LED alone degraded negligible amount of ACT but with the presence of TiO2/KAl(SO4)2, 95 % removal of 0.10-mM acetaminophen in 540-min irradiation time was achieved. The synthetic TiO2/KAl(SO4)2 presented better photocatalytic degradation of acetaminophen than commercially available Degussa P-25. The weak crystallinity of synthesized TiO2/NaAlO2 photocatalyst showed low photocatalytic degradation than TiO2/KAl(SO4)2. The optimal operational conditions were obtained in pH 6.9 with a dose of 1.0 g/L TiO2/KAl(SO4)2 at 30 °C. Kinetic study illustrated that photocatalytic degradation of acetaminophen fits well in the pseudo-first order model. Competitive reactions from intermediates affected the degradation rate of ACT, and were more obvious as the initial ACT concentration increased. 相似文献
296.
Zhifu Qi Tong Chen Sihong Bai Mi Yan Shengyong Lu Alfons Buekens Jianhua Yan Cora Bulmău Xiaodong Li 《Environmental science and pollution research international》2014,21(6):4697-4704
Thermal desorption is widely used for remediation of soil contaminated with volatiles, such as solvents and distillates. In this study, a soil contaminated with semivolatile polychlorinated biphenyls (PCBs) was sampled at an interim storage point for waste PCB transformers and heated to temperatures from 300 to 600 °C in a flow of nitrogen to investigate the effect of temperature and particle size on thermal desorption. Two size fractions were tested: coarse soil of 420–841 μm and fine soil with particles <250 μm. A PCB removal efficiency of 98.0 % was attained after 1 h of thermal treatment at 600 °C. The residual amount of PCBs in this soil decreased with rising thermal treatment temperature while the amount transferred to the gas phase increased up to 550 °C; at 600 °C, destruction of PCBs became more obvious. At low temperature, the thermally treated soil still had a similar PCB homologue distribution as raw soil, indicating thermal desorption as a main mechanism in removal. Dechlorination and decomposition increasingly occurred at high temperature, since shifts in average chlorination level were observed, from 3.34 in the raw soil to 2.75 in soil treated at 600 °C. Fine soil particles showed higher removal efficiency and destruction efficiency than coarse particles, suggesting that desorption from coarse particles is influenced by mass transfer. 相似文献
297.
Carolina Fernández-Ramos Oscar Ballesteros Alberto Zafra-Gómez Francisco Javier Camino-Sánchez Rosario Blanc Alberto Navalón José Luís Vílchez 《Environmental science and pollution research international》2014,21(6):4286-4296
The study describes the environmental monitoring of anionic surfactants―alcohol sulfates (AS) and alcohol ethoxysulfates (AES)—in marine sediments. Concentration values were obtained after pressurised liquid extraction (PLE) and liquid chromatography–tandem mass spectrometry analysis (LC–MS/MS). Samples were collected from a range of wastewater discharge points along the coast of the provinces of Huelva, Málaga, Granada and Almería. Urban, agricultural and industrial wastewaters are discharged at the selected 38 sampling sites. Principal component analysis was carried out in order to evaluate the distribution and behaviour of these compounds in these coastal environments. Evaluation of the data revealed that the behaviour and sources of AS and AES in marine sediments are different, and that the distribution of AES depends on the length of the alkyl chain, while the number of ethoxylated units is not relevant. Additionally, the 38 sampling sites can be grouped into only two types of outfalls according to their AS distribution. The concentration of compounds in sediment samples ranged from 7.52 to 13.50 mg kg?1 for AS, from 3.04 to 10.68 mg kg?1 for AES–C12Ex and from 3.83 to 11.56 mg kg?1 for AES–C14Ex. 相似文献
298.
Some technical issues in managing PCBs 总被引:1,自引:0,他引:1
Zhifu Qi Alfons Buekens Jie Liu Tong Chen Shengyong Lu Xiaodong Li Kefa Cen 《Environmental science and pollution research international》2014,21(10):6448-6462
Polychlorinated biphenyls (PCBs) were important industrial chemicals featuring high thermal and chemical stability and low flammability. They were widely used as dielectric and thermal fluid in closed electro-technical applications (transformers, capacitors…) and also in numerous dispersive uses, ranking from auto-copying paper to sealant or coatings. During the 1960s, severe environmental consequences started becoming apparent. The stability of PCBs contributed to their persistence in the environment, their lipophilic character to bio-magnification. Fish-eating species seemed threatened in their existence. In Japan and in Taiwan, thousands of people consumed PCB-contaminated oil. The production of PCBs stopped completely during the 1980s. Usage could continue in closed applications only. In this paper, particular attention is given to two issues: the cleaning of PCB electric transformers and the potential impact of PCB-containing building materials. Other contributions will cover the management and treatment of PCB-contaminated soil, sludge or fly ash. The complete survey is being prepared by request of the Knowledge Center for Engineers and Professionals. 相似文献
299.
Degree of phosphorus saturation of an Oxisol amended with biosolids in a long-term field experiment 总被引:1,自引:0,他引:1
Luís Reynaldo Ferracciú Alleoni Antonio Rodrigues Fernandes Murilo de Campos 《Environmental science and pollution research international》2014,21(8):5511-5520
When applied to agricultural soils, phosphate fertilizers and the mineral or organic compounds present in solid and/or liquid waste may raise phosphorus (P) content and increase soil P saturation. The degree of phosphorus saturation (DPS) is a good indicator of potential P loss from agricultural soils. The purpose of this study was to calculate the DPS of samples from an Oxisol amended for 5 years with biosolids and mineral fertilizer. DPS was calculated based on P, iron, and aluminum extracted by ammonium oxalate and oxalic acid (DPSox) or by Mehlich-1 solution (DPSM1). Treatments included NPK mineral fertilization (175 kg ha?1 of P), B1?=?19.02 t ha?1 of biosolids (350 kg ha?1 of P), B2?=?38.17 t ha?1 of biosolids (703 kg ha?1 of P), B3?=?76.26 t ha–1 of biosolids (1,405 kg ha?1 of P), and a control (no P added). Water-extractable P (WEP) was also measured. Critical levels of DPSox and DPSM1 (21 and 24 %, respectively) were only achieved in the topsoil (0–0.1 m) at the highest biosolid dose. Concentration of WEP was positively correlated to DPSox and DPSM1. The DPSM1 method may be an alternative to DPSox for assessing the environmental risk of P loss from soil into surface runoff. 相似文献
300.
Haiying Lu Linzhang Yang Sadaf Shabbir Yonghong Wu 《Environmental science and pollution research international》2014,21(14):8782-8791
To explain the detailed process involved in phosphorus removal by periphyton, the periphyton dominated by photoautotrophic microorganisms was employed in this study to remove inorganic phosphorus (P i ) from wastewater, and the removal kinetics and isotherms were then evaluated for the P i removal process. Results showed that the periphyton was capable of effectively removing P i that could completely remove the P i in 24 h at an initial P i concentration of 13 mg P L?1. Furthermore, the P i removal process by the periphyton was dominated by adsorption at initial stage (~24 h), which involved physical mechanistic process. However, this P i adsorption process was significantly influenced by environmental conditions. This work provides an insight into the understanding of phosphorus adsorption by periphyton or similar microbial aggregates. Graphical Abstract
? 相似文献