全文获取类型
收费全文 | 604篇 |
免费 | 8篇 |
国内免费 | 18篇 |
专业分类
安全科学 | 26篇 |
废物处理 | 22篇 |
环保管理 | 150篇 |
综合类 | 60篇 |
基础理论 | 147篇 |
污染及防治 | 163篇 |
评价与监测 | 39篇 |
社会与环境 | 19篇 |
灾害及防治 | 4篇 |
出版年
2022年 | 2篇 |
2021年 | 2篇 |
2020年 | 3篇 |
2019年 | 2篇 |
2018年 | 8篇 |
2017年 | 4篇 |
2016年 | 12篇 |
2015年 | 11篇 |
2014年 | 11篇 |
2013年 | 81篇 |
2012年 | 16篇 |
2011年 | 14篇 |
2010年 | 11篇 |
2009年 | 19篇 |
2008年 | 32篇 |
2007年 | 30篇 |
2006年 | 22篇 |
2005年 | 20篇 |
2004年 | 28篇 |
2003年 | 24篇 |
2002年 | 24篇 |
2001年 | 20篇 |
2000年 | 15篇 |
1999年 | 12篇 |
1998年 | 9篇 |
1997年 | 6篇 |
1996年 | 7篇 |
1995年 | 8篇 |
1994年 | 10篇 |
1993年 | 5篇 |
1992年 | 15篇 |
1991年 | 8篇 |
1990年 | 6篇 |
1989年 | 9篇 |
1988年 | 9篇 |
1987年 | 4篇 |
1986年 | 8篇 |
1985年 | 9篇 |
1984年 | 11篇 |
1983年 | 15篇 |
1982年 | 9篇 |
1981年 | 8篇 |
1980年 | 16篇 |
1979年 | 7篇 |
1978年 | 7篇 |
1977年 | 3篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有630条查询结果,搜索用时 15 毫秒
181.
Ashik Sathish Katherine Glaittli Ronald C. Sims Charles D. Miller 《Journal of Polymers and the Environment》2014,22(2):272-277
In addition to biodiesel production from algae, the production of other valuable bioproducts facilitates the development of an algae-based biorefinery platform. The goal of this study was to utilize the aqueous fraction from a novel algal wet lipid extraction procedure as the medium for the production of a bio product, poly(3-hydroxybutyrate) (PHB), via the growth of recombinant Escherichia coli. PHB yield was measured at 34 % of the E. coli dry cell mass, and was increased to 51 % when the algae aqueous medium was supplemented with glucose. While the addition of inorganic nutrients to the aqueous phase did not increase PHB production or growth of E. coli, growth of E. coli was observed to increase with the supplementation of carbon substrate (glucose). The addition of carbon rich waste to the aqueous fraction of wastewater-derived algae may in the future provide a sustainable alternative. Future research will be directed at evaluating this concept to develop a sustainable process for the production of bioplastics through an algae-based biorefinery platform. 相似文献
182.
Ronald A. Burt Gregory L. Christians Samuel P. Williams David J. Wilson 《Environmental monitoring and assessment》2001,72(3):297-326
Two dense nonaqueous phase liquid (DNAPL) tracer tests werecarried out in a shallow aquifer north of Fort Worth, TX. i-Propanolwas used as the nonpartitioning tracer; n-hexanol and n-octanol werethe partitioning tracers. Field data, mathematical modeling, theresults of column tests, and field tracer tests with NaCl were usedin designing the DNAPL tracer tests. The results indicated the presenceof DNAPL at both sites tested; semi-quantitative estimates of theamounts of DNAPL present were obtained by mathematical modeling.Interpretation was complicated by heterogeneity of the aquifer andmass transport effects. 相似文献
183.
Robert L. Stenburg Ronald R. Horsley Robert A. Herrick Andrew H. Rose JR. 《Journal of the Air & Waste Management Association (1995)》2013,63(2):114-120
The particle and gas properties that profoundly affect design and performance of fly ash precipitators are discussed and evaluated in this section. Relation of the coal burned to these properties and to the precipitator gas cleaning problem is broadly examined. The need for a high order of technology consistently applied to cope successfully with the wide and often uncertain variations in coal and ash properties encountered in precipitation practices is emphasized. 相似文献
184.
Andrew H. Rose JR. Robert L. Stenburg Morton Corn Ronald R. Horsley Daniel R. Allen Paul W. Kolp 《Journal of the Air & Waste Management Association (1995)》2013,63(4):297-309
A survey of academic programs in air pollution control was made. Results from the 127 schools reporting are tabulated by state. Faculty involved in air pollution instruction are identified. Some conclusions and recommendations are presented. 相似文献
185.
Ronald P. Young James L. DuBard Leslie E. Sparks 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1518-1522
Part I of this work has shown that electrical breakdown in dust layers obeys Paschen's Law, but occurs at applied field values which appear too small to initiate the breakdown. In this paper we will show how an effective dielectric constant characterizing the dust layer can be determined from ac dielectric measurements and the theory of Debye. When combined with an expression for the enhanced local electric field in the void spaces between particles in the layer, field strengths which are large enough to initiate electrical breakdown in the layer are predicted at relatively low values of applied field. The effect of temperature and dust layer thickness on the onset of electrical breakdown within the dust layer can also be explained by the dependence of the effective dielectric constant on these parameters. 相似文献
186.
187.
Ronald E. Sundberg 《Journal of the Air & Waste Management Association (1995)》2013,63(8):758-764
The application of air pollution control devices requires the prediction of overall collection efficiency from the particle size distribution of the dust and the fractional efficiency of the air pollution control device. The cumulative particle size distribution of dust resulting from industrial processes can usually be represented by a straight line on logarithmic probability paper or a log normal function. The fractional efficiency curves of many air pollution control devices such as cyclones or wet scrubbers can also be adequately represented by a log normal function. Only two parameters are required to define a log normal function, a median diameter and a geometric standard deviation. Both of these can easily be obtained from a plot on logarithmic probability paper. The overall collection efficiency has been found to be Very simply related to the four parameters required to define the log normal functions representing the particle size distribution and the collector fractional efficiency. These four parameters are: the mass median diameter and the geometric standard deviation of the dust size distribution, the cut diameter (50% efficiency diameter), and geometric standard deviation of collector fractional efficiency curve. Using this relationship the prediction of overall collection efficiency is greatly simplified with no loss of accuracy. 相似文献
188.
Ronald Harkov 《Journal of the Air & Waste Management Association (1995)》2013,63(7):783-784
The authors conducted a survey based on conjoint choice experiments in Milan, Italy, about mortality risk reductions delivered by hypothetical private behaviors and public programs, and used it to estimate the value of a prevented fatality (VPF) when the cause of death is cancer. Their estimate of the VPF is €4.2 million. The VPF is about €1 million larger when the risk reduction is delivered by a public program, but further analyses reveal that it is so only when the respondent believes that public programs are effective at reducing this particular type of mortality risk. This estimate of the VPF is higher than generic European Union–wide figures recommended by the European Commission Directorate-General for Environment (DG Environment) for environmental policy analyses, and is comparable to other VPFs that are appropriate for Italy, hazardous waste regulations, and enforcement-based cleanup programs. The authors use their VPF to compute the benefits of addressing leaking landfills, illegal disposal of hazardous wastes, and poor hazardous waste management practices in the provinces of Naples and Caserta in southern Italy. The authors also examine the importance of the discount rates, since the mortality benefits of remediation begin in 20 yr and are assumed to continue over 30 yr.
Implications: Cost-benefit analysis that includes monetized nonmarket goods and services such as adverse health and premature mortality effects has become a standard tool in project appraisal and policy decision-making. The authors' estimates of the mortality benefits of cleaning up hazardous waste sites in a region of southern Italy are much larger than previous calculations that relied on the guidelines by DG Environment, raising concerns that using one VPF for all member countries of the European Union, and/or VPF figures estimated in a private risk reduction setting, might considerably underestimate the benefits of cleanup policies. 相似文献
189.
190.
Michel P. Bonin William L. Flower Ronald F. Renzi Lawrence W. Peng 《Journal of the Air & Waste Management Association (1995)》2013,63(11):902-907
Abstract Optical measurements of particle size and concentration were made at the chromium plating tank and exhaust system at a commercial hexavalent chromium plating facility. Particles were examined at three locations in the exhaust system: 1) directly at the hexavalent chromium plating bath surface, 2) at the exit of a cyclone separator located in the exhaust system approximately three to four meters downstream of the bath, and 3) in the exhaust stack, downstream of the induced draft fan and all abatement devices. Particle diameters at the bath surface ranged from 0.3 to 25 μm. Downstream of the cyclone exit and mesh pad filters, particle top sizes were approximately 5 and 0.7 mm, respectively. On a mass basis, the collection efficiency of all abatement devices was 99.997%. Assuming that droplets in the flow consist primarily of water and chromium, correcting the total particle mass flow against water content gives a chromium emission rate of 64,000 μg/hr, which compares favorably with a value of 77,000 μg/hr measured with EPA methods. This initial agreement, which should be validated through additional measurements over a broad range of flow conditions, raises the possibility of continuous monitoring for chromium metal emissions using particle size/mass as a surrogate. 相似文献