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91.
Glycerine supply currently exceeds its demand by a significant margin as it is formed as by-product in biodiesel production. Different routes for its utilisation are currently being looked into, especially ones that would allow its use as a fuel addition. However these routes are not as energy efficient as its direct combustion.Previously glycerine and other very low cetane number calorific liquids were thought impossible to be used as fuels in compression ignition engines. We have developed a combustion cycle that permits the utilisation of glycerine as a fuel in a compression ignition engine without the need for pilot fuels or cetane improving additives. The paper discusses the results of glycerine combustion in standard unmodified Lister-Petter and Deutz compression ignition engines.  相似文献   
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On-site septic systems require appropriate soil characteristics to provide effective wastewater treatment. The objective of this study was to evaluate siting practices and treatment efficacy of on-site septic systems within the Cannonsville Reservoir watershed (115900 ha) in the state of New York. Using digital soil survey data, a database of on-site conditions was developed from more than 1100 existing septic system siting records. Soil map units were grouped into four classes based on their suitability to meet common septic system design criteria. A geographic information system was found to be a useful tool for assessment and visual display of septic system and landscape information. Geographic information system analysis indicated that while 80% of soils in the watershed were found to have characteristics that interfere with septic system function, 69% of septic systems installed were of designs suited for soils with no or few restrictive parameters. Since the designs of many septic systems have relied heavily on horizontal distance to streams (mean = 130 m) to provide adequate treatment, potential failures would lead to discharge of compounds of environmental concern, such as phosphorus, with public health implications. The results imply that many septic systems functioning in the watershed are in need of design improvements.  相似文献   
94.
The degradability of several degradable polymers was examined using three types of degradation environments. These include exposure in a laboratory-scale composting test system containing material representative of the organic fraction of municipal solid waste (MSW), exposure in a thermal hydrolytic environment consisting of water at 60‡C, and exposure in a thermal-oxidative, dry oven environment of 60‡C. The results of the investigation clearly indicate that, in addition to chemical and biological activity which can lead to polymer degradation, physical restructuring and reorganization of the macromolecular structure may also occur at temperatures typically found in a compost environment, resulting in changes in the mechanical properties of the polymer films. In the case of the polyethylene-modified polymers evaluated in this study, all behaved similarly, but differently from the other polymer types. The polyethylene-based films appeared to be susceptible to oxidative degradation and should degrade in a composting environment providing that there is sufficient air in contact with the film for a sufficient period of time. However, when exposed in a laboratory composter, it appears that although ideal temperature-time curves may be obtained, the test time period was insufficient in comparison to the induction period required to achieve the desired thermal oxidative degradation. Issued as NRCC No. 37620.  相似文献   
95.
This paper reports results from two studies that test a refinement of the equity sensitivity construct first in an experimental setting and second in a field setting. Results from Study 1 show that benevolents express tolerance for both overreward and underreward relative to entitleds and equity sensitives and that benevolents report relatively high levels of satisfaction regardless of reward condition. Study 1 results also show that manipulation of outcomes produce a more dramatic effect on satisfaction than does manipulation of inputs. Results from Study 2 reveal significantly different exchange ideologies for benevolents and entitleds and show that entitleds place more importance on pay whereas benevolents place more importance on the work itself. For both benevolents and entitleds, there is a positive correlation between assessments of distributive justice and job satisfaction. Implication of the findings both for equity theory research and the practice of management are discussed.  相似文献   
96.
Summary In Queensland, Australia, instream resources planning ranges from "fragmentary" to overlooked. But the State of Queensland, with engineer dominant water management, is only a little behind some other Australian States and Western countries in evaluating the environmental uses and values of river systems. Management is pragmatic about its abundant water endowment! Highly contrasting biophysical environments, from arid to tropical rainforest, as well as a dominance of ephemeral river systems should not preclude instream assessment. The new coastal $A430 million, Burdekin Falls Dam, the "1800's dream" has radically altered that river and delta region for economically amorphous agricultural purposes and, seemingly, to encourage crocodiles to recreate. In comparison, the "urbanised" Brisbane River is the focus of southern state water use competition issues such as flooding, eutrophication, turbidity, public access, preservation of river islands, sand and gravel mining, and recreation. A veritable host of river related management authorities preside!Dr Diana Day is trained as a fluvial geomorphologist and a water policy analyst. Her research has focused on natural resources management especially related to water and soil/land assets. Dr Day is an editor of the newAustralian Journal of Soil and Water Conservation. Her many publications include a recent book entitledWater and Coal -Industry, Environment and Institutions in the Hunter Valley, N.S.W., published by The Australian National University, Canberra, where until recently she was a Research Fellow. Dr Day is currently a Water Planner in the public sector.  相似文献   
97.
Intensified surface mining, power generation, and smelting operations in the Hunter River lowlands, NSW, Australia have posed numerous new environmental management problems. Legislative controls over water, soils, and land use management have been clearly insufficient and remain so. The complex range of environmental changes is challenging government agencies as well as coal developers. While water demands are increasing in the region the proportionally greatest competitors are power generation and irrigation. Comprehensive regional water quality assessment is inadequate and divided between a number of agencies with fragmentary interests. Coal development inquiries signal further controversy over appropriate management solutions and are an ongoing phenomenon in the region. The early 1980s resource boom has been followed by lower rates of economic growth, which have resulted in disparate agency responses to major ongoing environmental questions. While issue attention cycles are often remarkably short in environmental management, matters of water, land, and air quality require intensive and ongoing monitoring and policy development.  相似文献   
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99.
A recent turn towards a more contextually sensitive apprehension of the challenge of making everyday life less resource hungry has been partly underwritten by widespread evidence that the environmental values people commonly profess to hold do not often translate into correspondingly low impact actions. Yet sometimes the contexts of everyday life can also conspire to make people limit their consumption without ever explicitly connecting this to the environmental agenda. This paper considers this phenomenon with reference to UK studies from both ends of the generational spectrum. The first questioned how older people keep warm at home during winter and the second examined how young people get rid of no longer wanted possessions. Both found that, though the respondents involved were acting in certain ways that may be deemed comparatively low impact, they were hitherto relatively indifferent to the idea of characterising these actions as such. We outline three ways in which sustainability advocates might respond to the existence of such “inadvertent environmentalists” and consider how they might inspire studies that generate fresh intervention ideas instead of lingering on the dispiriting recognition that people do not often feel able to act for the environment.  相似文献   
100.
Testing the Accuracy of Population Viability Analysis   总被引:3,自引:0,他引:3  
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