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101.
Shortcoming associated with past water demand studies are evaluated. To overcome these shortcomings, pooled, time series, cross section data from -6, Sweden, are used in an ordinary Least squares analysis to estimate the demand for residential water. Elasticities for five variables, including price and income, are estimated. An approach for the conduct of future water demand studies is suggested.  相似文献   
102.
Two gasoline qualities, European unleaded certified gasoline (EUCG) and California phase 2 reformulated gasoline (P2 RFG), were analysed. EUCG contained about twice the amount of alkyl benzenes compared to P2 RFG and a large amount of cyclohexane. As a balance, P2 RFG contained higher amounts of isooctane and MTBE. The gasolines were burned in a premixed laminar flame burner at 1 atm and at about stoichiometric fuel/air ratio. The species profiles were measured using on-line GC/MS. About 40 compounds were be detected in the gasoline flames. The EUCG resulted in formation of more reactive and toxic compounds. The combustion profiles of the fuel components showed a similar slope, which suggests that the fuel components burn quite independently of each other. Ethene and propene were the dominating species produced from the two gasolines. Commonly, substantial amounts of higher alkenes were found. Combustion of P2 RFG produced higher amounts of isobutene, propene, propyne, propadiene and methanol compared to combustion of EUCG. The high amount of isobutene is reasonably a result of high concentration of isooctane and MTBE in the fuel. The high amount of methanol formed is probably due to the MTBE present in the gasoline. EUCG produced significantly higher amounts of 1,3-butadiene, which quite likely is formed from the cyclohexane in the fuel. The benzene profiles from both gasolines shows an almost constant level up to 800 microm from the burner surface; this is probably due to formation of benzene from alkyl benzenes.  相似文献   
103.

Emission inventories (EIs) are the fundamental tool to monitor compliance with greenhouse gas (GHG) emissions and emission reduction commitments. Inventory accounting guidelines provide the best practices to help EI compilers across different countries and regions make comparable, national emission estimates regardless of differences in data availability. However, there are a variety of sources of error and uncertainty that originate beyond what the inventory guidelines can define. Spatially explicit EIs, which are a key product for atmospheric modeling applications, are often developed for research purposes and there are no specific guidelines to achieve spatial emission estimates. The errors and uncertainties associated with the spatial estimates are unique to the approaches employed and are often difficult to assess. This study compares the global, high-resolution (1 km), fossil fuel, carbon dioxide (CO2), gridded EI Open-source Data Inventory for Anthropogenic CO2 (ODIAC) with the multi-resolution, spatially explicit bottom-up EI geoinformation technologies, spatio-temporal approaches, and full carbon account for improving the accuracy of GHG inventories (GESAPU) over the domain of Poland. By taking full advantage of the data granularity that bottom-up EI offers, this study characterized the potential biases in spatial disaggregation by emission sector (point and non-point emissions) across different scales (national, subnational/regional, and urban policy-relevant scales) and identified the root causes. While two EIs are in agreement in total and sectoral emissions (2.2% for the total emissions), the emission spatial patterns showed large differences (10~100% relative differences at 1 km) especially at the urban-rural transitioning areas (90–100%). We however found that the agreement of emissions over urban areas is surprisingly good compared with the estimates previously reported for US cities. This paper also discusses the use of spatially explicit EIs for climate mitigation applications beyond the common use in atmospheric modeling. We conclude with a discussion of current and future challenges of EIs in support of successful implementation of GHG emission monitoring and mitigation activity under the Paris Climate Agreement from the United Nations Framework Convention on Climate Change (UNFCCC) 21st Conference of the Parties (COP21). We highlight the importance of capacity building for EI development and coordinated research efforts of EI, atmospheric observations, and modeling to overcome the challenges.

  相似文献   
104.
The institutional and legislative framework of Swedish environmental protection is presented with special reference to the role of consultation in the policy process. The functions and duties of the National Environment Protection Board, the Franchise Board for Environment Protection, the Environment Advisory Board, and the Product Control Board are outlined. The main thrust of the 1969 Environment Protection Act, the 1972 Hazardous Products Control Act, and the environmental impact assessment requirements of the Planning and Building Legislation is presented. The character of consultation within this framework is also discussed, with reference to the role of public participation and of organized regulated interests. It is found that the main functions of consultation in policy-making are “feeding back on former policy,” “foreseeing future policies,” and “canvassing for consensus.” In the stage of policy clarification, consultation is found to be a means of “catering for compliance” and “creating coherence.” In policy implementation, consultation is an important means of gathering information from parties possibly affected by implementative decisions.  相似文献   
105.
North Scandinavian bank voles (Clethrionomys glareolus) differ from south Scandinavian conspecifics both in population dynamics and in activity, social behaviour, density-related sensitivity in sexual maturation and in reproduction. Some ecologists think that cyclically fluctuating rodents are particularly aggressive, at least in certain cycle phases. This hypothesis was tested in dyadic encounters between animals from southern and northern Sweden, respectively. Univariate analyses showed significant differences between regions in four separate behavioural traits, but not in behaviour related to aggression. Laboratory breeding for several generations did not affect the level of aggressivity. Multivariate analyses revealed two main components of activity and sociability, both with regional variation. Activity components (also including “freezing” behaviour) were chiefly related to age while sociability showed mainly regional variation. Differences observed may be due to the geographic location or earlier cyclicity, as the cyclic pattern was weak at the time when the test animals were sampled. An adaptation to high-density situations appears likely as the sympatric field vole (Microtus agrestis) shows similar regional differences although it lives in a different habitat. Cyclic animals appear to disperse at increasing densities while non-cyclic animals show clumped distributions. Received: 19 February 1996/Accepted after revision: 17 August 1996  相似文献   
106.
Sludge from gullies, on two types of streets with different traffic intensity, was investigated using two recommended EU methods for leachability testing of waste: a two-stage batch test and an up-flow percolation test. The main purpose of this investigation was to gain more knowledge about these leaching test methods to be able to make future decisions on the general applicability of the proposed tests. A number of parameters were determined in the sludge as well as in the eluates obtained from the two leaching tests. These include pH, conductivity, dissolved organic carbon and inorganic ions as chloride ions. A number of metals as Cd, Cr, Cu, Hg, Ni and Zn, were determined by inductive coupled plasmamass spectrometry and organic compounds were screened by high performance liquid chromatography-diode array UV detection and gas chromatography-mass spectrometry. It was found that the concentrations of metals and organic compounds in the sludge were several orders of magnitudes higher than the actual eluate concentrations. For all metals the concentrations were well below the proposed limit values for non-hazardous waste included in the Council decision document 2003/33/EC. Generally, concentrations obtained in batch test were equal or higher than from percolation tests. The repeatability of the percolation and the batch test were in average 28 and 17%, respectively.  相似文献   
107.
While new environmental policies and procedures often are developed incrementally, they can also result from crises or other significant events. In situations where policies and procedures are introduced in response to a crisis, questions about the strengths and weaknesses of existing mechanisms, and the extent to which they can be used to address concerns, may be ignored. This paper explores the complexities of introducing new policies and processes where planning systems and procedures already exist. Drinking water source protection policies that are being developed in response to the tragic events in Walkerton, Ontario, Canada serve as the context for the inquiry. Three case study watersheds were selected to reflect the diversity of municipal jurisdictions and water supply systems in Ontario. A content analysis was undertaken on regulatory and non-regulatory policy documents to determine the extent to which they addressed elements of the multi-barrier approach for drinking water safety. Findings from the research reveal considerable evidence of the multi-barrier approach in the policy and guiding documents analyzed. Policy development in response to a crisis can advance progress on the issue of drinking water safety and coincide with emerging governance strategies. Policy effectiveness may be enhanced by considering existing policies as well as contextual and jurisdictional differences.  相似文献   
108.
The results of (14)C measurements in the annual tree rings from the Ignalina Nuclear Power Plant (INPP) surroundings, Lithuania, for the period of its operation from 1984 to 2002 are presented. The terrestrial samples, mainly moss and related soil, are studied in places as well. The tree rings have shown slightly enhanced (14)C activity due to operation of the nuclear power plant. The maximal calculated normalized (14)C release of 11TBqGW(e)(-1)year(-1) and the maximal effective dose of 2.0x10(-3)mSvyear(-1) resulting from the (14)C were estimated for 1999. For other years of INPP operation these values are lower. The excess of (14)C specific activity measured in the moss and soil samples from moss-covered sites near the nuclear power plant (up to 0.5km) showed highly elevated (14)C contents (up to 813pMC), probably indicating releases of particulate material.  相似文献   
109.
Many organisms show differences between males and females in growth rate and crucial life history parameters, such as longevity. Considering this, we may expect levels of toxic metabolic by-products of the respiratory chain, such as reactive oxygen species (ROS), to vary with age and sex. Here, we analyse ROS levels in female Australian painted dragon lizards (Ctenophorus pictus) and their offspring using fluorescent probes and flow cytometry. Basal level of four ROS species (singlet oxygen, peroxynitrite, superoxide and H2O2) measured with a combined marker, and superoxide measured specifically, varied significantly among families but not between the sexes. When blood cells from offspring were chemically encouraged to accelerate the electron transport chain by mitochondrial uncoupling, net superoxide levels were three times higher in daughters than sons (resulting in levels outside of the normal ROS range) and varied among mothers depending on offspring sex (significant interaction between maternal identity and offspring sex). In offspring, there were depressive effects on ROS of size-controlled relative clutch size, which relies directly on circulating levels of vitellogenin, a confirmed antioxidant in some species. Thus, levels of reactive oxygen species varies among females, offspring and in relation to reproductive investment in a manner that makes its regulatory processes likely targets of selection.  相似文献   
110.
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