全文获取类型
收费全文 | 284篇 |
免费 | 3篇 |
国内免费 | 38篇 |
专业分类
安全科学 | 8篇 |
废物处理 | 12篇 |
环保管理 | 47篇 |
综合类 | 83篇 |
基础理论 | 45篇 |
污染及防治 | 93篇 |
评价与监测 | 31篇 |
社会与环境 | 5篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 4篇 |
2022年 | 3篇 |
2021年 | 4篇 |
2020年 | 5篇 |
2019年 | 3篇 |
2018年 | 7篇 |
2017年 | 4篇 |
2016年 | 11篇 |
2015年 | 11篇 |
2014年 | 14篇 |
2013年 | 21篇 |
2012年 | 22篇 |
2011年 | 25篇 |
2010年 | 11篇 |
2009年 | 29篇 |
2008年 | 18篇 |
2007年 | 15篇 |
2006年 | 9篇 |
2005年 | 7篇 |
2004年 | 8篇 |
2003年 | 18篇 |
2002年 | 10篇 |
2001年 | 5篇 |
2000年 | 13篇 |
1999年 | 6篇 |
1998年 | 6篇 |
1997年 | 4篇 |
1996年 | 5篇 |
1995年 | 4篇 |
1994年 | 6篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 4篇 |
1984年 | 2篇 |
1982年 | 2篇 |
1978年 | 1篇 |
排序方式: 共有325条查询结果,搜索用时 31 毫秒
281.
Enhancement of copper and cadmium adsorption on kaolin by the presence of humic acids 总被引:18,自引:0,他引:18
The competitive adsorption equilibrium isotherms of Cu2+ and Cd2+ on kaolin have been measured at 298 K, in the presence and the absence of humic acids (HAs). HAs were found to enhance the metal adsorption capacity of mineral surfaces, in particular kaolin. This enhancement was also observed in the competitive adsorption of copper and cadmium on kaolin and kaolin–HA complex. This competitive adsorption shows that the presence of Cd2+ has not an important effect on Cu2+ adsorption, whereas a dramatic decrease is observed on the adsorption of Cd2+ in the presence of Cu2+. The Freundlich isotherm equation was found to provide an excellent fit to the experimental data. These results were compared with the independent adsorption of both heavy metals. 相似文献
282.
Sea salts (seven brands from six commercially-available sources) were dissolved in water to develop 30 g/l solutions, and selected water quality characteristics were then monitored for 96 h. One or more water quality characteristics changed significantly during the 96 h period in six of the reconstituted sea salts. Measured characteristics of sea water diluted to 30 g/l demonstrated no changes during the observation period. The sea salts from different sources also demonstrated differences in absolute concentrations of some characteristics measured. Application of the Biotic Ligand Model to predict copper toxicity to the bivalve Mytilus edulis in solutions of the salts tested yielded 96-h median-lethal concentrations that ranged from 2 to 13 μg/l. Since water quality affects toxicity of many environmental pollutants, the source of the sea salt and equilibration time should be considered when planning toxicity tests. 相似文献
283.
Phenotypic plasticity in Scenedesmus incrassatulus (Chlorophyceae) in response to heavy metals stress 总被引:1,自引:0,他引:1
Peña-Castro JM Martínez-Jerónimo F Esparza-García F Cañizares-Villanueva RO 《Chemosphere》2004,57(11):1629-1636
The microalgae genus Scenedesmus is commonly found in freshwater bodies, wastewater facilities and water polluted with heavy metals. Phenotypic plasticity in Scenedesmus has been documented in response to a wide variety of conditions; however, heavy metals have not been comprehensively documented as phenotypic plasticity inducers. In this study, we report the phenotypic plasticity of Scenedesmus incrassatulus (a non-spiny, four-cell coenobium forming species) in response to EC50 value of copper, cadmium and hexavalent chromium. S. incrassatulus was grown in batch cultures in the presence of each metal. Chlorophyll-a content, cell size, parameters derived from the schematic energy-flux model for photosystem II, and morphotype expressions were recorded. Divalent cation metals induced unicellular forms, and hexavalent chromium produced out-of-shape coenobia corresponding to various stages of autospore formation. The changes induced by divalent metals were interpreted as phenotypic plasticity, because they were always associated to population doublings and were reversible when toxicant pressure was removed (only for Cu). Copper was the best inductor of unicellular forms and also affected significantly all the photosynthetic parameters measured. The developed morphotypes could confer ecological advantages to S. incrassatulus in metal stressed environments. 相似文献
284.
Nitrogen oxides(NO_x:NO,NO_2)are a concern due to their adverse health effects.Diesel engine transport sector is the major emitter of NO_x.The regulations have been strengthened and to comply with them,one of the two methods commonly used is the selective catalytic reduction of NO_xby NH_3(NH_3-SCR),NH_3being supplied by the in-situ hydrolysis of urea.Efficiency and durability of the catalyst for this process are highly required.Durability is evaluated by hydrothermal treatment of the catalysts at temperature above 800°C.In this study,very active catalysts for the NH_3-SCR of NO_xwere prepared by using a silicoaluminophosphate commercial zeolite as copper host structure.Characterizations by X-ray diffraction(XRD),scanning electron microscopy(SEM)and temperature programmed desorption of ammonia(NH_3-TPD)showed that this commercial zeolite was hydrothermally stable up to 850°C and,was able to retain some structural properties up to950°C.After hydrothermal treatment at 850°C,the NO_xreduction efficiency into NH_3-SCR depends on the copper content.The catalyst with a copper content of 1.25 wt.%was the most active.The difference in activity was much more important when using NO than the fast NO/NO_2reaction mixture. 相似文献
285.
Effects of copper chloride on formation of polychlorinated dibenzo-p-dioxins in model waste incineration 总被引:1,自引:0,他引:1
Combustion experiments in a laboratory-scale fluidized-bed reactor were conducted to elucidate the effects of copper chloride as a catalyst on polychlorinated dibenzo-p-dioxins (PCDDs) formation in municipal waste incineration. We used model wastes with and without copper chloride (CuCl2 · 2H2O), both of which contained polyvinyl chloride as a chlorine source. Combustion temperature was set to 900 °C, and the amount of air supplied was twice the stoichiometric ratio. The experimental setup was carefully planned to suppress the influences of experimental conditions except the waste composition. Results of these experiments showed that copper chloride in the waste increased the amount of PCDDs formed and made the homologue profile to shift towards the highly chlorinated species. Copper chloride contributes to the PCDDs formation by promoting chlorination, whereby the reaction is important in that organic matter is chlorinated directly by copper compounds. Copper chloride did not exert a great influence on the isomer distribution patterns of PCDDs, while there appeared a significant difference in the case of PCDFs. This points out the difference of the major formation mechanisms between PCDDs and PCDFs. PCDDs are less formed by the catalytic reactions from carbon/polycyclic aromatic hydrocarbons than PCDFs in our experimental conditions. 相似文献
286.
Summary In this work we attained a successful cysticidal effect against Vahlkampfia hartmanni cysts using mild to moderate experimental conditions, regarding light energy delivered and concentrations of aluminium phthalocyanine
tetrasulfonate (AlPCS4). The dark and phototoxic activity of AlPCS4 towards the cyst forms of Vahlkampfia hartmanni, a freshwater amoeba previously isolated from keratitic patients, were tested. The photosensitized deactivation of the cyst
form of this amoeba depends mainly on the concentration of AlPCS4 and the light fluence rate as well as the total fluence
delivered during the irradiation process. Upon irradiation of the cyst suspension at 100 mW/cm2 for 10 minutes in the presence of 3 μ M AlPCS4, a complete photodamaging effect on the cysts was induced. The photodamaging
effect on Vahlkampfia cysts induces a state of inability of the cysts to excyst, vacuolation of the inner contents as well as a significant damage
of the outer cyst wall upon microscopic examination. 相似文献
287.
开发玉龙铜矿的经济评价 总被引:1,自引:0,他引:1
本文分析了开发玉龙铜矿床的优势条件.对玉龙铜矿的开发进行了效益评估,并提出了可持续开发对策. 相似文献
288.
289.
Measuring heavy metal migration rates in a low-permeability soil 总被引:2,自引:0,他引:2
Heavy metals at high concentrations are often toxic to living organisms, and their environmental toxicity depends on soil
properties. It has long been thought that in clay-rich, low-permeability soils, heavy metals are bound to soil particles,
and thus there are only few toxicity risks. This study questioned this perception and tested heavy metal mobility in such
a soil, of the London Clay series, using a benchtop centrifuge. Soil columns were placed in the centrifuge and were infiltrated
with solutions of Cu, Ni and Zn ions, while the centrifuge was running at three different gravity levels, at 5,280, 2,600
and 1,300 gravities. The measured rates of migration of Cu, Ni and Zn ions were extrapolated down to 1 gravity, which represents
field conditions, the conditions for which an assessment of risk due to metal toxicity would be needed. It was found that
heavy metal movement was significant in London Clay, Ni being the most mobile metal in the study, followed by Zn and then
Cu ions. Centrifuge infiltration tests were proven to be a valuable tool in the study and quantification of metal mobility
in low-permeability soil, because they were easy to run and precise in predicting metal movement in London Clay.
Electronic Publication 相似文献
290.
Peggy?Gunkel Estelle?Roth Bernard?FabreEmail author 《Environmental Chemistry Letters》2004,2(2):99-103
We studied copper uptake by maize grown on soils that have been contaminated with CuSO4. In soil the total copper level ranged from 24 to 135 mg kg–1. The copper distribution in soil fractions was assessed by sequential extraction, showing that anthropogenic copper is mainly concentrated in oxides fractions. The copper concentration of maize at the maturity stage reached values from 36.3 to 65.9 mg kg–1 compared to copper levels usually found in non-contaminated crops (5–30 mg kg–1). Here we demonstrate that copper can be accumulated by maize and that copper concentration in maize can be predicted by equations including copper concentration of soil fractions. 相似文献