全文获取类型
收费全文 | 2332篇 |
免费 | 48篇 |
国内免费 | 27篇 |
专业分类
安全科学 | 98篇 |
废物处理 | 94篇 |
环保管理 | 715篇 |
综合类 | 142篇 |
基础理论 | 497篇 |
环境理论 | 1篇 |
污染及防治 | 608篇 |
评价与监测 | 160篇 |
社会与环境 | 74篇 |
灾害及防治 | 18篇 |
出版年
2023年 | 15篇 |
2022年 | 24篇 |
2021年 | 22篇 |
2020年 | 25篇 |
2019年 | 25篇 |
2018年 | 32篇 |
2017年 | 34篇 |
2016年 | 48篇 |
2015年 | 39篇 |
2014年 | 41篇 |
2013年 | 307篇 |
2012年 | 76篇 |
2011年 | 94篇 |
2010年 | 91篇 |
2009年 | 64篇 |
2008年 | 102篇 |
2007年 | 103篇 |
2006年 | 115篇 |
2005年 | 95篇 |
2004年 | 64篇 |
2003年 | 92篇 |
2002年 | 84篇 |
2001年 | 26篇 |
2000年 | 37篇 |
1999年 | 27篇 |
1998年 | 43篇 |
1997年 | 31篇 |
1996年 | 32篇 |
1995年 | 30篇 |
1994年 | 26篇 |
1993年 | 22篇 |
1992年 | 27篇 |
1991年 | 24篇 |
1990年 | 26篇 |
1989年 | 22篇 |
1988年 | 28篇 |
1987年 | 20篇 |
1986年 | 22篇 |
1985年 | 25篇 |
1984年 | 42篇 |
1983年 | 32篇 |
1982年 | 36篇 |
1981年 | 37篇 |
1980年 | 26篇 |
1979年 | 42篇 |
1978年 | 28篇 |
1977年 | 22篇 |
1976年 | 19篇 |
1971年 | 11篇 |
1970年 | 9篇 |
排序方式: 共有2407条查询结果,搜索用时 15 毫秒
771.
William R. King 《Journal of the Air & Waste Management Association (1995)》2013,63(3):275-277
There are economic and regulatory incentives for considering alternatives to the direct land disposal of solvent-bearing hazardous waste streams (EPA Hazardous Waste Codes: F001, F002, F003, F004, and F005). These alternatives include recycle/reuse (including use as a fuel substitute), destruction of a stream's solvent component, and treatment prior to land disposal. This paper reviews these three waste management alternatives and discusses their applicability to solvent waste streams having various physical characteristics. Seven waste treatment techniques which may be used to handle solvent wastes are described: incineration, agitated thin-film evaporation, fractional distillation, steam stripping, wet oxidation, carbon adsorption, and activated sludge biological treatment. 相似文献
772.
Christopher E. Johnson William C. Malm Gerald Persha John V. Molenar James R. Hein 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1261-1265
An automated scanning densitometer system developed to estimate visibility-related parameters from photographic slides was tested in comparison to similar teleradiometric measurements. Parameters such as target-sky contrast, visual range, atmospheric light extinction coefficient, and plume and layered contrast can be estimated using this system; however, only target-sky radiance ratios and standard visual ranges were compared. More than 1600 concurrent densitometer and teleradiometer data pairs from eight National Park Service air quality and visibility monitoring locations in the western United States were analyzed using the techniques of correlation, linear regression, average bias and difference calculation, and cumulative frequency distribution generation. Correlation coefficients were good, especially with middle-range camera vistas around 50 km distant. Regression slopes approached unity with intercepts near zero. Average bias introduced into the determination of radiance ratios from slides ranged from near zero to 6 percent, depending on target distance. Standard visual range data distributions compared favorably at the low end with some minor differences at the high end. 相似文献
773.
William H. Prokop Hinrich L. Bohn 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1332-1338
Biofilter technology has been applied recently to treating rendering odors. Soil beds are one class of biofilter but as yet have not been used for this application. Although wet scrubbers have been a traditional method of odor control, their capital and operating costs are impacting more severely. Soil bed systems are less expensive to install and operate. A soil bed system was installed at a rendering plant in Arizona and has been in operation since September 1983. The soil bed treats 1100 m3/h (650 cfm) of cooker noncondensables with a surface area of 420 m2(4500 ft2). The pressure drop across the soil bed is 5 cm (2 in.) of water. Odor sensory testing with the MTRI forced-choice triangle dynamic olfactometer indicates an odor removal efficiency of 99.9 percent is obtained with the soil bed. Soil bed odor removal efficiency is equivalent to or superior than that for incineration or scrubbing of high intensity odors from the rendering process. Recent experience during this past winter indicates a soil bed is a viable method for operation in a northern climate with severe winter weather conditions. Also, monitoring of the leachate from a soil bed indicated no contamination. 相似文献
774.
775.
John Wooley William W. Nazaroff Alfred T. Hodgson 《Journal of the Air & Waste Management Association (1995)》2013,63(8):1114-1120
Liquid laundry and hand dish washing detergents contain volatile organic compounds, Including ethanol, that may be liberated during use and contribute to photochemical air pollution. In this study, the release of ethanol to the atmosphere during simulated household use of liquid detergents was measured. Three replicate experiments, plus a blank, were conducted In a 20-m3 environmental chamber for each of four conditions: “typical” dish washing (DT), “high-release” dish washing (DH), “typical” laundry (LT), and “high-release” laundry (LH). Average amounts of ethanol transferred to the atmosphere per use (and the fraction of ethanol used so liberated) were 32 mg (0.038) for DT, 100 mg (0.049) for DH, 18 mg (0.002) for LT, and 110 mg (0.011) for LH. Thus, a large fraction of the ethanol added to wash solutions with liquid detergents is discharged to the sewer rather than transferred to the atmosphere during use. 相似文献
776.
Dennis D. Baldocchi Randall White J. William Johnston 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1549-1556
A wind tunnel study was conducted to determine the optimal design features of a large, open-top chamber, as needed for pollution exposure studies on mature trees. An optimally-designed, open-top chamber must minimize the incursion of ambient air through its opening and maintain a uniform treatment concentration throughout the chamber. The design features of interest are the diameter and height of the chamber and the deflection angle and opening size of any frustum that may be mounted on top of a model chamber. Design specifications depend on the turbulence regime about the chamber, which is influenced by the nature of the surrounding vegetation. Consequently, our investigation was performed on scale-model, open-top chambers in a wind tunnel populated with a model coniferous forest. Turbulence measurements demonstrated the similarity between the turbulence regime of the model and a natural forest. A hydrocarbon tracer was injected into the wind tunnel flow to characterize chamber performance. The main design features of open-top chambers are the velocity of air exiting through the top and the relationship between the length scale of the turbulence and the diameter of the chamber opening. As exit velocities increase, the proportion of eddies with sufficient force to penetrate into the chamber decrease. Therefore, for equal volumetric air flows, smaller opening sizes increase the exit velocities and reduce the number and extent of ambient air incursions. Almost total exclusion of ambient air is achieved as the exit velocity of the air exceeds the magnitude of one standard deviation of the vertical wind velocity measured at the chamber top. The incursion of ambient air is also reduced when the diameter of the chamber opening is smaller than the characteristic length scale of the turbulence, a measure of mean eddy size. Frusta deflect air flow over the chamber. Three prototypes, with 30?, 45? and 60-degree angles were tested. A 30-degree frustum slightly improves the performance of the chamber and is more effective in preventing ambient air from entraining into the chamber opening than frusta with either a 45? or 60-degree angle. A flatter frustum allows for a smoother transition in the wind velocity streamline and is less apt to cause wake turbulence, as is the case with steeper frusta. Knowledge of the turbulence characteristics of plant canopies are readily available in the literature and can aid scientists and engineers in designing the optimal chamber and frusta dimensions for their particular application. Therefore, the empirical approach to chamber design can be avoided, and substantial savings can be realized. 相似文献
777.
William F. Jaynes Stephen A. Boyd 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1649-1653
Homoionic trimethylphenylammonium (TMPA)- and tetramethylammonium (TMA)-clays were prepared by Ion-exchange reactions using two smectite clays that differed in their cation exchange capacities and surface charge densities. These clays are referred to as a low-charge (SAC) and high-charge (SWa)-smectite. The organo-clays were evaluated as adsorbents of water soluble aromatic hydrocarbons including benzene, toluene, ethylbenzene, p-xylene, butylbenzene, and naphthalene. All of the aromatic hydrocarbons tested were effectively removed from water by the low-charge TMPA-smectite. The low-charge TMA-smectite was an effective adsorbent for benzene but was ineffective in the removal of the alkylbenzenes and naphthalene from water. The effect of surface charge on the adsorption properties of TMPA-smectite was pronounced. The uptake of benzene and toluene by the high-charge TMPA-smectite was greatly reduced as compared to the low-charge TMPAsmectite. These results suggest the utility of TMPA-smectite as a liner material for petroleum storage containers and waste disposal reservoirs. The use of TMPA-smectite in conjunction with Na-smectite would provide a barrier with the ability to impede the flow of water and to effectively adsorb dissolved organic contaminants. 相似文献
778.
Mary K. Stinson Herbert S. Skovronek William D. Ellis 《Journal of the Air & Waste Management Association (1995)》2013,63(1):96-103
A pilot-scale soil washing process, patented by BioTrol, Inc., was demonstrated on soil contaminated by wood treating waste, primarily pentachlorophenol (PCP) and creosote-derived polynuclear aromatic hydrocarbons (PAHs). Although soil washing was the main object of this demonstration, the treatment train that was evaluated included two other BioTrol technologies for treatment of waste streams from the soil washer. The three technologies were: ? The BioTrol Soil Washer (BSW)—a volume reduction process, which uses water to separate contaminated soil fractions from the bulk of the soil. ? The BioTrol Aqueous Treatment System (BATS)—a biological water treatment process. ? The Slurry Bioreactor (SBR)—a BioTrol biological slurry treatment process conducted in an EIMCO BIOLIFTtm reactor. The sandy soil at the site, consisting of less than 10 percent of fines, was well suited for treatment by soil washing. The soil washer was evaluated in two tests on soil samples containing 130 ppm and 680 ppm of PCP, respectively. The BSW successfully separated the feed soil (dry weight basis) into 83 percent of washed soil, 10 percent of woody residues, and 7 percent of fines. The washed soil retained about 10 percent of the feed soil contamination while 90 percent of the feed soil contamination was contained within the woody residues, fines, and process water. The soil washer achieved up to 89 percent removal of PCP and 88 percent of total PAHs, based on the difference between their levels in the as-is (wet) feed soil and the washed soil. PCP concentrations of 14 ppm and 87ppm in the washed soil were achieved from PCP concentrations of 130 ppm and 680ppm in the feed soil. Concentrations of total PAHs were reduced from 247 ppm to 42 ppm and 404 ppm to 48 ppm, respectively, in the two tests. The BATS degraded up to 94 percent of PCP in the process water from soil washing. PAH removal could not be determined due to low influent concentrations. The SBR achieved over 90 percent removals of PCP and 70 to 90 percent removals of PAHs from the slurry of contaminated fines from soil washing. However, steady state operation was not achieved during the single test and the results were variable. Cost of a commercial-scale soil washing, assuming use of all three technologies, was estimated to be $168 per ton of soil treated. Incineration of woody material accounts for 76 percent of the cost. 相似文献
779.
780.
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