全文获取类型
收费全文 | 5487篇 |
免费 | 27篇 |
国内免费 | 25篇 |
专业分类
安全科学 | 131篇 |
废物处理 | 296篇 |
环保管理 | 432篇 |
综合类 | 829篇 |
基础理论 | 1356篇 |
环境理论 | 1篇 |
污染及防治 | 1357篇 |
评价与监测 | 398篇 |
社会与环境 | 712篇 |
灾害及防治 | 27篇 |
出版年
2023年 | 43篇 |
2022年 | 76篇 |
2021年 | 60篇 |
2020年 | 29篇 |
2019年 | 42篇 |
2018年 | 75篇 |
2017年 | 90篇 |
2016年 | 111篇 |
2015年 | 70篇 |
2014年 | 146篇 |
2013年 | 417篇 |
2012年 | 168篇 |
2011年 | 242篇 |
2010年 | 214篇 |
2009年 | 219篇 |
2008年 | 254篇 |
2007年 | 250篇 |
2006年 | 240篇 |
2005年 | 207篇 |
2004年 | 190篇 |
2003年 | 215篇 |
2002年 | 176篇 |
2001年 | 254篇 |
2000年 | 161篇 |
1999年 | 101篇 |
1998年 | 41篇 |
1997年 | 58篇 |
1996年 | 53篇 |
1995年 | 60篇 |
1994年 | 64篇 |
1993年 | 59篇 |
1992年 | 58篇 |
1991年 | 61篇 |
1990年 | 66篇 |
1989年 | 52篇 |
1988年 | 56篇 |
1987年 | 54篇 |
1986年 | 55篇 |
1985年 | 41篇 |
1984年 | 47篇 |
1983年 | 47篇 |
1982年 | 48篇 |
1980年 | 30篇 |
1979年 | 32篇 |
1978年 | 29篇 |
1977年 | 28篇 |
1976年 | 28篇 |
1974年 | 31篇 |
1973年 | 30篇 |
1972年 | 27篇 |
排序方式: 共有5539条查询结果,搜索用时 15 毫秒
231.
Forty-six bacterial cultures, including one culture collection strain, thirty from the rhizosphere of Alyssum murale and fifteen from Ni-rich soil, were tested for their ability to tolerate arsenate, cadmium, chromium, zinc, mercury, lead, cobalt, copper, and nickel in their growth medium. The resistance patterns, expressed as minimum inhibitory concentrations, for all cultures to the nine different metal ions were surveyed by using the agar dilution method. A large number of the cultures were resistant to Ni (100%), Pb (100%), Zn (100%), Cu (98%), and Co (93%). However, 82, 71, 58 and 47% were sensitive to As, Hg, Cd and Cr(VI), respectively. All cultures had multiple metal-resistant, with heptametal resistance as the major pattern (28.8%). Five of the cultures (about of 11.2% of the total), specifically Arthrobacter rhombi AY509239, Clavibacter xyli AY509235, Microbacterium arabinogalactanolyticum AY509226, Rhizobium mongolense AY509209 and Variovorax paradoxus AY512828 were tolerant to nine different metals. The polymerase chain reaction in combination with DNA sequence analysis was used to investigate the genetic mechanism responsible for the metal resistance in some of these gram-positive and gram-negative bacteria that were, highly resistant to Hg, Zn, Cr and Ni. The czc, chr, ncc and mer genes that are responsible for resistance to Zn, Cr, Ni and Hg, respectively, were shown to be present in these bacteria by using PCR. In the case of, M. arabinogalactanolyticum AY509226 these genes were shown to have high homology to the czcD, chrB, nccA, and mer genes of Ralstonia metallidurans CH34. Therefore, Hg, Zn, Cr and Ni resistance genes are widely distributed in both gram-positive and gram-negative isolates obtained from A. murale rhizosphere and Ni-rich soils. 相似文献
232.
Electrochemical degradation applied to the metabolites of Acid Orange 7 anaerobic biotreatment 总被引:1,自引:0,他引:1
The electrochemical oxidation of the biotic degradation products of the textile dye C.I. Acid Orange 7 (AO7) was achieved using a boron doped diamond electrode (BDD). Tests were performed with model solutions of the biotic degradation products, sulphanilic acid (SA) and 1-amino-2-naphthol (AN), and also with real effluents obtained in experiments carried out in an up-flow anaerobic sludge blanket (UASB) reactor, fed with a simulated textile effluent containing AO7, working in mesophilic or thermophilic conditions. Bulk electrolysis was studied using two different supporting electrolytes - NaCl and Na(2)SO(4). The influence of initial metabolite concentration and current density on the electrodegradation rates of the biotic products was investigated. For the UASB effluents, oxidation tests were carried out for different electrolytes and at different current densities. Samples were collected at pre-selected intervals and absorbance measurements, chemical oxygen demand (COD) and total organic carbon (TOC) tests and high performance liquid chromatography (HPLC) analysis were performed. Results have shown an almost complete elimination of the persistent pollutants and a COD removal higher than 70% for both AN and SA. For the UASB effluents, COD removals between 45% and 90% and TOC removals varying from 19% to 41% were obtained. 相似文献
233.
The present study deals with the biodegradation of catechol through co-metabolism with glucose in aqueous solution as primary substrate in an upflow anaerobic sludge blanket (UASB) reactor. Batch studies indicated that the 1000mgl(-1) glucose concentration was sufficient to cometabolize and degrade catechol in an aqueous solution up to a concentration of 1000mgl(-1). The reactor operated at 35+/-2 degrees C, and at a constant hydraulic retention time of 8h with a gradual stepwise increase in catechol concentration from 100 to 1000mgl(-1) along with glucose as a cosubstrate. The results showed that the catechol was successfully mineralized in an UASB reactor in which microbial granulation was achieved with only glucose as the substrate. The reactor showed > or = 95% COD removal efficiency with 500-1000mgl(-1)catechol concentration in the feed and a glucose concentration of 1500mgl(-1) as a cosubstrate. Similar efficiency was obtained at a constant catechol concentration of 1000mgl(-1) with 500-1000mgl(-1) glucose concentration. Once the reactor got acclimatized with catechol, higher concentrations of catechol can be mineralized with a minimum amount of glucose as the cosubstrate without affecting the performance of the UASB reactor. 相似文献
234.
Somerset VS Klink MJ Baker PG Iwuoha EI 《Journal of environmental science and health. Part. B》2007,42(3):297-304
The behavior of an amperometric organic-phase biosensor consisting of a gold electrode modified first with a mercaptobenzothiazole self-assembled monolayer, followed by electropolymerization of polyaniline in which acetylcholinesterase as enzyme was immobilized, has been developed and evaluated for organophosphorous pesticide detection. The voltammetric results have shown that the formal potential shifts anodically as the Au/MBT/PANI/AChE/PVAc thick-film biosensor responded to acetylthiocholine substrate addition under anaerobic conditions in selected organic solvent media containing 2% v/v 0.05 M phosphate buffer, 0.1 M KCl (pH 7.2) solution. Detection limits in the order of 0.147 ppb for diazinon and 0.172 ppb for fenthion in acetone-saline phosphate buffer solution, and 0.180 ppb for diazinon and 0.194 ppb for fenthion in ethanol-saline phosphate buffer solution has been achieved. 相似文献
235.
Gutiérrez-Ortiz JI de Rivas B López-Fonseca R Martín S González-Velasco JR 《Chemosphere》2007,68(6):1004-1012
The catalytic activity and selectivity of manganese zirconia mixed oxides were evaluated for the oxidation of two common chlorinated pollutants found in waste streams, namely 1,2-dichloroethane (DCE) and trichloroethylene (TCE). Mixed oxides with varying Mn-Zr content were prepared by coprecipitation via nitrates, and subsequent calcination at 600 degrees C for 4 h in air. These catalysts were characterised by means of several techniques such as atomic emission spectrometry, N2 adsorption-desorption, powder X-ray diffraction, temperature-programmed desorption of ammonia, pyridine adsorption followed by diffuse reflectance infrared spectroscopy and temperature-programmed reduction with hydrogen. The active catalytic behaviour of Mn-Zr mixed oxides was ascribed to a substantial surface acidity combined with readily accessible active oxygen species. Hence, the mixed oxide with 40 mol% manganese content was found to be an optimum catalyst for the combustion of both chlorocarbons with a T50 value around 305 and 315 degrees C for DCE and TCE oxidation, respectively. The major oxidation products were carbon dioxide, hydrogen chloride and chlorine. It was observed that the formation of both CO2 and Cl2 was promoted with Mn loading. 相似文献
236.
Experiments were carried out to evaluate the use of some agroindustrial wastes as supports in solid state cultures for the biodegradation of crude oil Maya in static column reactors over 15-20 days periods. Spent compost and cane bagasse wastes showed superior qualities over peat moss waste as support candidates with the advantage that they contain appreciable densities of autochthonous microorganisms in the order of 10(2) cfu g(-1). Mercuric chloride (2%) was able to completely inhibit growth of these microfloras. Biodegradation was enhanced in the presence of the IMP consortium and highest when microflora from cane bagasse only was the bioaugmentation partner (180.7 mg kg(-1) day(-1)). Combination of these waste materials (3:1 ratio, respectively) was observed to significantly biodegrade the crude oil by approximately 40% in 15 days from an initial concentration of 10,000 mg kg(-1) with a four order of magnitude increase in microbial density during this period. Spent compost and cane bagasse wastes are veritable solid support candidates for use in the biodegradation of crude oil polluted systems. 相似文献
237.
Rao PS Ansari MF Gavane AG Pandit VI Nema P Devotta S 《Environmental monitoring and assessment》2007,128(1-3):323-328
Petroleum refineries are largest chemical industries that are responsible for the emission of several pollutants into the
atmosphere. Benzene is among the most important air pollutants that are emitted by petroleum refineries, since they are involved
in almost every refinery process. Volatile organic compounds (VOCs) are a major group of air pollutants, which play a critical
role in atmospheric chemistry. These contribute to toxic oxidants, which are harmful to ecosystem, human health and atmosphere.
The variability of pollutants is an important factor in determining human exposure to these chemicals. The ambient air concentrations
of benzene were measured in several sites around the Digboi petroleum refinery, near the city of Gowahati in northeast India,
during winter and summer 2004. The seasonal and spatial variations of the ambient air concentrations of this benzene were
investigated and analyzed. An estimation of the contribution of the refinery to the measured atmospheric levels of benzene
was also performed. The ambient air mixing ratios of benzene in a large area outside the refinery was generally low, in ppbv
range, much lower than the ambient air quality standards. This article presents the temporal and spatial variation of air
pollution in and around petroleum refinery and showed that no health risk due to benzene is present in the areas adjacent
to the refinery. 相似文献
238.
Jiménez-Ramos MC Barros H García-Tenorio R García-León M Vioque I Manjón G 《Environmental pollution (Barking, Essex : 1987)》2007,145(2):391-394
The characterisation by ICP-MS of an isolated Pu-U hot particle originating from the nuclear weapons accident in Palomares (Spain) shows, for the first time, that its uranium content is highly enriched in (235)U. The enrichment has been confirmed by independent analyses of two surface soil samples collected in a heavily contaminated area close to the impact point of one of the bombs. This finding clarifies better the composition of the weapons involved in the accident and is of importance when the inventory of U and Pu in the contaminated area are to be calculated. 相似文献
239.
Real time remote monitoring of air pollutants and their online transmission to the web using internet protocol 总被引:1,自引:0,他引:1
Anjaneyulu Y Jayakumar I Bindu VH Rao PV Sagareswar G Ramani KV Rao TH 《Environmental monitoring and assessment》2007,124(1-3):371-381
Recent advances in both information and sensor technologies have enabled the development of Real Time Remote Monitoring (RTRM)
capabilities for environmental management. An online and real time remote monitoring system for air pollution has been designed
and installed at a traffic police station at Punjagutta in Hyderabad, India. The system is optimized using electrochemical
sensors and a real time particulate matter analyzer. The system also monitors meteorological parameters such as temperature,
humidity, rainfall, barometric pressure, wind speed and wind direction. The system periodically monitors both pollution and
meteorological parameters at pre- programmed intervals of hr during peak periods and 1 hr during non peak periods of the day and continuously uploads to a predestinated web site (www.appcb.org/home.htm)
using File Transfer Protocol. The web site renders a quick, simple and graphical display of air pollution levels and meteorological
parameters and their significance to humans. The present paper highlights design considerations of a pollution monitoring
system, system hardware and software requirements and practical limitations and future directions for real time remote monitoring
of air pollution. 相似文献
240.