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791.
Reul-Chen CK Ross C Steele NL Winer AM 《Journal of the Air & Waste Management Association (1995)》2005,55(2):241-247
To reduce public exposure to diesel particulate matter (DPM), the California Air Resources Board has begun adoption of a series of rules to reduce these emissions from in-use heavy-duty vehicles. Passive diesel particulate filter (DPF) after-treatment technologies are a cost-effective method to reduce DPM emissions and have been used on a variety of vehicles worldwide. Two passive DPFs were interim-verified in California and approved federally for use in most 1994--2002 engine families for vehicles meeting min engine exhaust temperature requirements for successful filter regeneration. Some vehicles, however, may not be suited to passive DPFs because of lower engine exhaust temperatures. The purpose of this study was to determine the applicability of two types of passive DPFs to solid waste collection vehicles, the group of vehicles for which California recently mandated in-use DPM reductions. We selected 60 collection vehicles to represent the four main types of collection vehicle duty cycles--rolloffs, and front-end, rear, and side loaders--and collected second-by-second engine exhaust temperature readings for one week from each vehicle. As a group, the collection vehicles exhibited low engine exhaust temperatures, making the application of passive DPFs to these vehicles difficult. Only 35% of tested vehicles met the temperature requirements for one passive DPF, whereas 60% met the temperature requirements for the other. Engine exhaust temperatures varied by vehicle type. Side and front-end loaders met the engine exhaust temperature requirements in the greatest number of cases with approximately 50-90% achieving the required regeneration temperatures. Only 8-25% of the rear loader and roll-off collection vehicles met the engine exhaust temperature requirements. Solid waste collection vehicles represent a diverse fleet with a variety of duty cycles. Low engine exhaust temperatures will need to be addressed for successful use of passive DPFs in this application. 相似文献
792.
Lory JA Massey RE Zulovich JM Hoehne JA Schmidt AM Carlson MS Fulhage CD 《Journal of environmental quality》2004,33(3):1114-1123
Concerns about manure P and water quality have prompted new regulations imposing P limits on land application of manure. Previous research established that P limits increase land needs for animal feeding operations. We evaluated the effect of N, annual P, and rotation P limits on the feasibility of manure management. A mechanistic model characterized manure management practices on 39 swine operations (20 unagitated lagoon and 19 slurry operations) in five states (Iowa, Missouri, North Carolina, Oklahoma, and Pennsylvania). Extensive information collected from each operation was used to determine effects of manure storage type, ownership structure, and application limits on attributes of manure management. Phosphorus limits had substantially greater effect on slurry operations, increasing land needs 250% (0.3 hectares per animal unit [AU]) and time for manure application 24% (2.5 min AU(-1)) for rotation P limits and 41% (4.4 min AU(-1)) for annual P limits. Annual P limits were infeasible for current land application equipment on two operations and had the greatest effect on time and costs because they required all but three slurry operations to reduce discharge rate. We recommend implementing rotation P limits (not to exceed crop N need) to minimize time effects, allow most farmers to use their current manure application methods, and allow manure to fulfill crop N and P needs in the year of application. Phosphorus limits increased potential manure value but would require slurry operations to recover at least 61% of manure value through manure sales. Phosphorus limits are likely to shape the U.S. swine industry through differential effects on the various sectors of the swine industry. 相似文献
793.
Legislation regarding seat belt use in Canada is a provincial/territorial responsibility. Each of the 13 jurisdictions has enacted legislation and set the penalties regarding non-use of seat belts and appropriate child restraint systems. The federal government regulates occupant restraint systems and child restraints. In addition, Transport Canada (TC) gathers annual survey data on the use of seat belts and child restraints on Canadian roads and provides research support. National coordination toward the Canadian Road Safety Vision 2010 goal of a 40% reduction in fatalities and serious injuries related to non-belt/child restraint use and a 95% restraint usage rate is provided by the Canadian Council of Motor Transport Administrators' (CCMTA) National Occupant Restraint Program (NORP). The paper examines the history of legislation, provincial/territorial penalties, NORP, and TC involvement in promoting the use of occupant restraints. 相似文献
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The background of this work is the international decision process with regard to the selection of chemicals to be assessed with priority. In order to stress the precautionary principle, mass flows were analysed rather than concentrations, threshold values, etc., as preferred by the chemical legislation (which still excludes the marine area). Lindane, hexachlorobenzene (HCB), trichloroacetic acid and its sodium salt, medium-chained chlorinated paraffins and tributyltin (TBT) were selected due to their great relevance for the marine area. Trichloroacetic acid is an interesting model compound on account of its accidental formation by degradation of volatile chlorinated hydrocarbons and during chlorination processes. In addition, a hypothetical compound was modelled, representing a highly water-soluble substance with low vapour pressure. The balancing area is the Baltic Sea and its catchment area. In order to model the substance flows, the 'Input/Output-load model' has been developed. The model quantifies the shift and the distribution of a yearly load of the substance investigated from the terrestrial-limnic into the marine compartment (Baltic Sea). Water-soluble substances, which are usually considered to be of no concern, may enter the sea in great amounts and, if not degradable, remain there. It turned out to be necessary to take into account remobilisation, unintended formation and point as well as line-sources. 相似文献
796.
Four Illinois communities with different sociode-mographic compositions and at various stages of planning for solid waste
management were surveyed to determine the influence of sociodemographic variables and planning stages on the factors that
motivate recycling behavior. A factor analysis of importance ratings of reasons for recycling and for not recycling yielded
five factors interpreted as altruism, personal inconvenience, social influences, economic incentives, and household storage.
The four communities were shown to be significantly different in multivariate analyses of the five motivational factors. However,
attempts to explain these community differences with regression analyses, which predicted the motivational factors with dummy
codes for planning stages, a measure of self-reported recycling behavior, and sociodemographic measures were unsatisfactory.
Contrary to expectation, the solid waste management planning stages of the cities (curbside pickup, recycling dropoff center,
and planning in progress) contributed only very slightly to the prediction of motivational factors for recycling. Community
differences were better explained by different underlying motivational structures among the four communities. Altruistic reasons
for recycling (e.g., conserving resources) composed the only factor which was similar across the four communities. This factor
was also perceived to be the most important reason for recycling by respondents from all four communities. The results of
the study supported the notion that convenient, voluntary recycling programs that rely on environmental concern and conscience
for motivation are useful approaches to reducing waste. 相似文献
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