全文获取类型
收费全文 | 170篇 |
免费 | 3篇 |
专业分类
安全科学 | 14篇 |
废物处理 | 4篇 |
环保管理 | 27篇 |
综合类 | 22篇 |
基础理论 | 52篇 |
环境理论 | 2篇 |
污染及防治 | 42篇 |
评价与监测 | 5篇 |
社会与环境 | 4篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 1篇 |
2020年 | 1篇 |
2019年 | 3篇 |
2018年 | 5篇 |
2017年 | 2篇 |
2016年 | 9篇 |
2015年 | 4篇 |
2014年 | 3篇 |
2013年 | 15篇 |
2012年 | 4篇 |
2011年 | 3篇 |
2010年 | 15篇 |
2009年 | 7篇 |
2008年 | 12篇 |
2007年 | 10篇 |
2006年 | 6篇 |
2005年 | 6篇 |
2004年 | 7篇 |
2003年 | 10篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1993年 | 1篇 |
1991年 | 3篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1980年 | 1篇 |
1978年 | 3篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1966年 | 1篇 |
1963年 | 1篇 |
1961年 | 1篇 |
1950年 | 1篇 |
排序方式: 共有173条查询结果,搜索用时 15 毫秒
151.
Jodi D. Hoffman Diana W. Bianchi Lisa M. Sullivan Brenda L. Mackinnon Jamie Collins Fergal D. Malone T. Flint Porter David A. Nyberg Christine H. Comstock Radek Bukowski Richard L. Berkowitz Susan J. Gross Lorraine Dugoff Sabrina D. Craigo Ilan E. Timor-Tritsch Stephen R. Carr Honor M. Wolfe Mary E. D'Alton 《黑龙江环境通报》2008,28(13):1204-1208
152.
Hermle S Günthardt-Goerg MS Schulin R 《Environmental pollution (Barking, Essex : 1987)》2006,144(2):703-714
Young Populus tremula, Salix viminalis, Betula pendula and Picea abies trees were grown together in large open-top chambers. The treatments were: without or with (Cu/Zn/Cd/Pb=640/3000/10/90 mg kg-1) metal contamination in the topsoil, irrigation pH 3.5 or 5.5, and acidic or calcareous subsoil. Growth, metal allocation to foliage and wood, as well as leaf gas exchange were measured. Biomass was reduced in P. tremula and B. pendula by the metal-contaminated topsoil relative to uncontaminated topsoil, whereas in P. tremula photosynthesis and transpiration were decreased. These effects were related to the elevated foliar Zn accumulation in P. tremula. S. viminalis showed a significant reduction in growth and an increased Zn and Cd accumulation on acidic vs. calcareous subsoil. Acidic irrigation produced only a few significant effects. P. abies showed the lowest metal uptake and no growth response to metal contamination. 相似文献
153.
Diagnosis of abiotic and biotic stress factors using the visible symptoms in foliage 总被引:1,自引:0,他引:1
Vollenweider P Günthardt-Goerg MS 《Environmental pollution (Barking, Essex : 1987)》2006,140(3):562-571
Visible symptoms in the foliage of trees are recorded to monitor the effects of abiotic and biotic stress. Difficulties are reported in diagnosing the origin of stress. The present paper discusses several diagnostic criteria which are usable in different species for a better determination of the stress factor type. A new diagnosis scheme to differentiate between classes of abiotic and biotic stress factors is supplied. Abiotic stress generates gradients of symptoms. The symptom specificity is determined by the degree of interaction between the stress factor and plant defense system. Symptoms caused by abiotic stress and natural autumnal senescence can be morphologically different or undistinguishable according to the stress and plant species. With biotic stress, the class of parasitic is generally recognizable on the basis of the visible symptoms. Structurally and physiologically based explanations of the symptom morphology are still missing for many stress factors. 相似文献
154.
155.
L. K. Porter 《Journal of contaminant hydrology》1995,20(3-4)
Deep percolation of nitrate can contribute to the deterioration of groundwater resources. Leaching of nitrate is a complex process affected by fertilizer and irrigation practices, efficiency of N use by the crop, and how the soil's water holding capacity and water transmission properties are affected by soil texture. Depleted (15NH4)2SO4 fertilizer at N rates of 0, 125, 250 and 375 kg ha−1 was applied annually for 3 years to continuous corn grown within three different water regimes. This time period and the labeled N permitted an evaluation of N use efficiency by the crop and NO3 leaching and carryover on a Weld silty clay loam, a fine-textured soil, typical of the “hardland” soils of the semi-arid Great Plains. Three water regimes, W1 ( 1.5 ET), W2 ( ET) and W3 ( 0.8 ET), were used. Beneath each plot within each water regime, Duke-Haise vacuum trough extractors were installed under undisturbed soil profiles at 1.22-m depth to measure weekly percolate and the NO3 concentration in the percolate. The corn was harvested in the fall in the dent stage to measure the total above-ground biomass N uptake. Soil profiles (1.8 m) were sampled annually in the fall after crop harvest to determine NO3---N in the soil or carryover.Great variability was encountered in measuring the amount of extractor water and its NO3 content under each water regime, which made estimates of N03 leaching losses unreliable. Also, the variability demonstrates formidable problems in quantifying percolation losses with vacuum trough extractors under undisturbed fine-textured soil profiles. With the highest N rate of 376 kg ha−1 yr−1 and within the water regime W1, where leaching was expected to be greatest, only 1% of the cumulative labeled N applied was found in extractor waters and most movement of the labeled N into extractors occurred the third year. The 125-kg-ha−1 yr−1 fertilizer N rate significantly increased the crop yield over the unfertilized plots without increasing residual NO3---N accumulation; whereas fertilizer N rates of > 125 kg ha−1 yr−1 did not appreciably increase plant yields over the 125-kg-ha−1-N rate, but did appreciably increase residual NO3. 相似文献
156.
This paper reviews the use of ion exchange resins for adsorbing proteins and viruses and for purifying viral suspensions. The analysis of resin performance under different conditions provides some information on the fundamental nature of virus/protein-resin interaction.A variety of systems are considered and the influence of factors such as resin type, resin pretreatment, chemical characteristics of the solution and virus type on adsorption are discussed and compared. Analogies are made between virus-host and virus-resin interactions, both of which are specific to the virus-host or virus-resin pair. Consideration is given to the use of proteins as models for virus adsorption. The use of viral parameters such as iso-electric point and the amino acid content of the protein coat for predicting virus adsorption behavior is also discussed. Anion exchange resins were found to be more effective virus sorbents than cation exchange resins. Cation exchange resins were ineffective in low ionic strength media, while anion exchange resins were most effective in low ionic strength media. 相似文献
157.
Arlindo Canigo Gomes Isolina Cabral Gon?alves Maria Norberta de Pinho John Jefferson Porter 《Water environment research》2007,79(5):498-506
The filtration characteristics of simulated dyeing effluents containing Acid Orange 7, sodium sulfate, and a pH buffer made of acetic acid and sodium acetate is described using a commercially available nanofiltration membrane. The original membrane filtration properties were characterized with deionized water to provide a baseline of membrane performance. At high volumetric concentration of the test solutions, greater than 98% rejection of dye and sodium sulfate were obtained. Rejection of buffering chemicals was approximately 50% in all experiments, giving a permeate water not suitable for reuse in most dyeing operations. The final composite concentrate had a chemical oxygen demand (COD) value > 2000 mg/L. No problems were encountered with anaerobic treatment of the concentrate obtained from the dyeing wastewater. Adjusting the sulfate concentration to give COD-to-sulfate ratios to 2.9, 5.4, and 18.2 in the reactor feed had no significant alterations in the performance of the upflow anaerobic sludge blanket reactor. 相似文献
158.
Sustainability has come to play a dominant discursive role in the UK planning system, particularly relating to urban regeneration. The purpose of this paper is to evaluate the role that sustainability plays in a major regeneration programme, known as Eastside, currently underway in Birmingham, the UK. That this £6 billion redevelopment is now widely talked about by such key players as Birmingham City Council and the Regional Development Agency, Advantage West Midlands, as having a central sustainability agenda points to the growing importance of the ideal of sustainability in planning and regeneration agendas. In this paper, we investigate in detail how and why sustainability has become part of the planning discourse for Eastside and critically evaluate what impact, if any, this is having on public policy decision-making. 相似文献
159.
Philip Heilman Jerry L. Hatfield Martin Adkins Jeffrey Porter Russell Kurth 《Journal of the American Water Resources Association》2004,40(2):333-345
ABSTRACT: Water quality issues in agriculture are growing in importance. A common theme is the provision of better information to decision makers. This study reports the trial of a prototype decision support system by the U.S. Department of Agriculture Natural Resources Conservation Service and the Agricultural Research Service in the NRCS Harrison County Field Office in 1998. Observed data collected at the Deep Loess Research Station (DLRS) near Treynor, Iowa, were extrapolated using a modified GLEAMS field scale simulation model that included a nitrogen leaching component and a crop growth component. An accounting tool was used to convert crop yield estimates into crop budgets. A model interface was built to specify the climate, soil, and topography of the field, as well as the management scenarios for the alternative management systems. For the Deep Loess Hills area of Harrison County, a total of six soil and slope groups, with 66 total combinations of management practices forming management systems, were defined and simulated based on previously calibrated data from DLRS. A multi‐objective decision support system, the Water Quality Decision Support System, or WQDSS, was used to examine the tradeoffs in a comprehensive set of variables affected by alternative management systems with farmers in Harrison County. The study concluded that a multiobjective decision support system should be developed to support conservation planning by the NRCS. Currently, a larger scale effort to improve water quality decision making is underway. 相似文献
160.
William A. Battaglin Earl M. Thurman Stephen J. Kalkhoff Stephen D. Porter 《Journal of the American Water Resources Association》2003,39(4):743-756
ABSTRACT: Most herbicides applied to crops are adsorbed by plants or transformed (degraded) in the soil, but small fractions are lost from fields and either move to streams in overland runoff, near surface flow, or subsurface drains, or they infiltrate slowly to ground water. Herbicide transformation products (TPs) can be more or less mobile and more or less toxic in the environment than their source herbicides. To obtain information on the concentrations of selected herbicides and TPs in surface waters of the Midwestern United States, 151 water samples were collected from 71 streams and five reservoir outflows in 1998. These samples were analyzed for 13 herbicides and 10 herbicide TPs. Herbicide TPs were found to occur as frequently or more frequently than source herbicides and at concentrations that were often larger than their source herbicides. Most samples contained a mixture of more than 10 different herbicides or TPs. The ratios of TPs to herbicide concentrations can be used to determine the source of herbicides in streams. Results of a two‐component mixing model suggest that on average 90 percent or more of the herbicide mass in Midwestern streams during early summer runoff events originates from the runoff and 10 percent or less comes from increased ground water discharge. 相似文献