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911.
James G. Edinger Morris H. McCutchan Paul R. Miller Bill C. Ryan Mark J. Schroeder Joseph V. Behar 《Journal of the Air & Waste Management Association (1995)》2013,63(11):882-886
On June 18, 19, and 20, 1970, two aircraft, a rawinsonde, two pibal stations, and four ground stations provided simultaneous samples of total oxidant, temperature, and winds up to 8000 ft in an area extending from Santa Monica, Calif., east to Redlands and north across the San Bernardino Mountains. It was shown that photochemical oxidant formed in the marine layer is vented up the slopes and over the crest of the San Bernardino Mountains during the day. Layers of high oxidant concentrations were detected above the inversion base, suggesting that some pollution is vented up the slopes and subsequently advected back to the south. The diurnal changes in the temperature inversion also contribute to the high concentration found above the inversion base. These processes result in multi-layers of pollution. The study suggests that oxidant air pollution is transported up to 80 mi to forested mountains, where severe damage to conifer species has been documented. 相似文献
912.
James E. Carson 《Journal of the Air & Waste Management Association (1995)》2013,63(7):523-528
Concern for the biological and ecological effects of heated water has resulted in legal actions that will prevent power companies from dumping the waste heat from the majority of their new generating units into rivers and lakes. Many nuclear- and fossil-fueled plants now under construction, and even some now online, are being required to change from once-through cooling systems to other methods, such as wet cooling towers, cooling ponds, and spray canals, despite higher costs and lower thermal efficiencies. Yet, these alternate cooling procedures are not without their own environmental problems. The primary weather change due to once-through cooling on a large water body is a small local increase in fogginess at the plant outfall. But the relative probability of significant local meteorological effects is much higher with alternate cooling procedures, since these reduce the area of heat and moisture transfer. It is therefore concluded that, from a meteorological point of view, the least undesirable way to dispose of waste heat is by using once-through cooling on large water bodies. 相似文献
913.
James H. Turner 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1182-1187
It has been amply demonstrated that there are reasons for improving the collection of fine participates. Some areas of research and development which may prove fruitful in extending fabric filter capabilities have been suggested. 相似文献
914.
Anthony F. Casalinuovo James M. Riddell 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1107-1109
For years educators have been striving for vocational realism in the classroom, that is, an in vivo work training program. Drawbacks to this system, however, have been student attitudes and conceptions of the nature of the programs. To the student population, vocational programs resembled the usual stereotype “school.” The solution to this problem was not simple. In order to achieve a real life simulation of work, teachers would need to grant additional freedom to students, which presents a calculated risk to the student and the instructor. 相似文献
915.
Wm. J. Veigele James H. Head 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1139-1140
The Prevention of Significant Deterioration (PSD) doctrine has been one of the most hotly contested aspects of U. S. air pollution law. In its present form, it exerts powerful influence on land-use planning and plant siting. It has worked in the past and will presumably work in the future to increase the amount of air pollution to which the average American is regularly exposed. It has serious technical flaws. Some alternative PSD policies which remedy these flaws are proposed. 相似文献
916.
Menachem Luria Kenneth J. Olszyna James F. Meagher 《Journal of the Air & Waste Management Association (1995)》2013,63(5):483-497
On June 5 and 6 of 1980, two parallel plume oxidation studies were carried out in the vicinity of the Tennessee Valley Authority's Colbert Steam Plant. One study was performed in a smog chamber into which stack gases were injected and mixed with ambient air. The other study included direct airborne sampling of the power plant plume. Atmospheric oxidation rates for the conversion of SO2 to SO4 2- and the removal rates of NO x (which is presumably the rate of NO3 - formation) were estimated for both studies. The SO2 to SO4 2- rate coefficients were found to be 0.022 ± 0.009 h-1 for both chamber experiments and the first airborne sampling day. For the second day, a rate constant of 0.041 ± 0.052 h-1 was estimated from the aircraft data. The large deviation in this value is explained by the fact that the plume from the power plant combined and reacted with the urban plume from the city of Florence, AL. The formation of a very large "O3 bulge" on this day is also attributed to the mixed plumes. The first order rate coefficients for NO x removal were estimated to be 0.27 ± 0.14 h-1 for both chamber experiments and the first airborne sampling day. A NO x removal rate could not be determined for the second airborne sampling day. 相似文献
917.
918.
Peter A. Gabele James O. Baugh Frank Black Richard Snow 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1168-1175
Exhaust and evaporative emissions were examined from vehicles fueled with methanol or a gasoline-methanol blend. Regulated automobile pollutants, as well as detailed hydrocarbons, methanol, and aldehydes were measured, and exhaust emission trends were obtained for vehicle operation over five different driving cycles. Results indicated that use of the blended fuel does not generally have any significant effect on base-line exhaust emission rates of regulated pollutants; however, emission rates of aldehydes increased during the Federal Test Procedure. Aldehyde emissions from the methanol-fueled car were roughly an order of magnitude higher than those resulting from blended fuel usage. The hydrocarbon composition of evaporative emissions with the blended fuel was similar to that with the base-line fuel except when canister breakthrough occurred. Evaporative emissions during breakthrough were comprised chiefly of N-butane. 相似文献
919.
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
920.
James J. Huntzicker Emily K. Heyerdahl Stephen R. McDow John A. Rau Wayne H. Griest Carolyn S. MacDougall 《Journal of the Air & Waste Management Association (1995)》2013,63(6):705-709
Organic and elemental carbon and a number of carboxylic acids and n-alkanes were measured in aerosol samples collected at three sites in the Ohio River Valley between October 1980 and August 1981. Approximately 100 filters were analyzed for organic and elemental carbon for each site. For the 11-month period organic and elemental carbon comprised about 19 percent of the total aerosol mass with about two-thirds of the carbon as organic. Regression analysis showed that the principal source of organic carbon was combustion. The measurements of the specific organic compounds indicated a weak biogenic component to the organic aerosol. 相似文献