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101.

As part of the studies related to the obligations of the UN Framework Convention on Climate Change, the Republic of Kazakhstan started activities to inventory greenhouse gas (GHG) emissions and assess of GHG mitigation options. The objective of this paper is to present an estimate of the possibility of mitigating GHG emissions and determine the mitigation priorities. It presents a compilation of the possible options and their assessment in terms of major criteria and implementation feasibility. Taking into account the structure of GHG emissions in Kazakhstan in 1990, preliminary estimates of the potential for mitigation are presented for eight options for the energy sector and agriculture and forestry sector. The reference scenario prepared by expert assessments assumes a reduction of CO2 emissions in 1996–1998 by about 26% from the 1990 level due to general economic decline, but then emissions increase. It is estimated that the total potential for the mitigation of CO2 emissions for the year 2000 is 3% of the CO2 emissions in the reference scenario. The annual reduction in methane emissions due to the estimated options can amount to 5%–6% of the 1990 level.

  相似文献   
102.
A semi-empirical mathematical model, Urban Street Model (USM), is proposed to efficiently estimate the dispersion of vehicular air pollution in cities. This model describes urban building arrangements by combining building density, building heights and the permeability of building arrangements relative to wind flow. To estimate the level of air pollution in the city of Krasnoyarsk (in Eastern Siberia), the spatial distribution of pollutant concentrations off roadways is calculated using Markov's processes in USM. The USM-predicted numerical results were compared with field measurements and with results obtained from other frequently used models, CALINE-4 and OSPM. USM consistently yielded the best results. OSPM usually overestimated pollutant concentration values. CALINE-4 consistently underestimated these values. For OSPM, the maximum differences were 160% and for CALINE-4 about 400%. Permeability and building density are necessary parameters for accurately modeling urban air pollution and influencing regulatory requirements for building planning.  相似文献   
103.
Chemical characterization to determine the organic and nitrogen fractions was performed on cloud water samples collected in a mountaintop site in Puerto Rico. Cloud water samples showed average concentrations of 1.09 mg L?1 of total organic carbon (TOC), of 0.85 mg L?1 for dissolved organic carbon (DOC) and of and 1.25 mg L?1 for total nitrogen (TN). Concentrations of organic nitrogen (ON) changed with the origin of the air mass. Changes in their concentrations were observed during periods under the influence of African dust (AD). The ON/TN ratios were 0.26 for the clean and 0.35 for the AD periods. Average concentrations of all these species were similar to those found in remote environments with no anthropogenic contribution. In the AD period, for cloud water the concentrations of TOC were 4 times higher and TN were 3 times higher than during periods of clean air masses associated with the trade winds. These results suggest that a significant fraction of TOC and TN in cloud and rainwater is associated to airborne particulate matter present in dust. Functional groups were identified using proton nuclear magnetic resonance (1H NMR) spectroscopy. This characterization led to the conclusion that water-soluble organic compounds in these samples are mainly aliphatic oxygenated compounds, with a small amount of aromatics. The ion chromatography results showed that the ionic species were predominantly of marine origin, for air masses with and without African dust influence, with cloud water concentrations of NO3? and NH4+ much lower than from polluted areas in the US. An increase of such species as SO42?, Cl?, Mg2+, K+ and Ca2+ was seen when air masses originated from northwest Africa. The changes in the chemical composition and physical properties of clouds associated with these different types of aerosol particles could affect on cloud formation and processes.  相似文献   
104.
This paper originated as a part of a comprehensive research project designed to develop ecologically sustainable, environmentally friendly, resource- and energy-saving industrial process technology for the production of a wide class of phosphorus containing substances. The essential feature of the research was designed for the replacement of tubular heat exchangers with Plate heat exchangers (PHEs) and for the installation of these units in new locations in the processes to optimally improve energy efficiency and to prevent pollution. Despite the severe operating conditions in the production of phosphoric acid PHEs of various designs find the application in these processes. For such a corrosive environment as a phosphoric acid production plant, the Hastelloy G30 alloy is used as the material for the plates and synthetic rubber EPDM is used as the material for inter-plate gaskets. The analysis of the data shows, that using mixed groupings of plates in the unit allows one to obtain optimal solutions. The simulation of barometric mixing condenser recycled water cooling with plate heat exchanger shows the possibility of an application which minimizes the waste water pollution by closing the condenser cooling water circuit. Software was developed for calculations of units working both with liquid and phase changing streams.  相似文献   
105.
The volcanic soils of southern Chile have demonstrated a high capacity to adsorb environmental pollutants, but for an industrial application, a stable solid material is necessary. The objective of this work was to produce a stable ceramic material through a process involving volcanic soil-polyurethane foam produced with recycled polyethylene terephthalate (PET)-polyols, and further thermal treatment. The selected foam formulation with 35.4% volcanic soil (< 63 microm) seems to be the most suitable for thermal treatment, with temperature steps at 700, 850, 1000 and 1200 degrees C. The porous ceramic material obtained has a stable solid form and an improved chlorophenols adsorption capacity (comparable to natural zeolites) that makes it suitable for advanced wastewater treatment and landfill leachate depuration.  相似文献   
106.
107.
This study was carried out in 32 communities neighbouring four Ramsar wetlands in Northern Greece. In particular, it concerns the study of local residents' attitude regarding the ways of management and exploitation of the wetlands and their sociological features, using the opinion poll method (1600 questionnaires were distributed). The aim of this investigation is the evaluation of findings for planning of effective management and conservation policy of wetlands, incorporating the opinions of local residents. Further protection of the wetlands, awareness of local residents of the value of wetlands, tourism or agriculture development (in some cases), as well as more governmental support, became obvious results from this research.  相似文献   
108.
Workers (n = 17 275) from 14 European Union (EU) member states provided data on job control, job dissatisfaction, perceived risk of occupational stress, and absence. For each state, level of research and development (R&D) activity was assessed. Associations between individual levels of control and occupational health were stronger where national R&D activity was higher. The moderation occurred for individuals' levels of control in relation to job dissatisfaction, perceived risk of occupational stress, and absence. The findings with job dissatisfaction and absence were replicated in a sample of workers from 10 Eastern European former Communist countries (n = 7926). Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
109.
This paper presents a methodology for the calculation of atmospheric stability classes in correlation with wind velocities for six sites of the Greek territory, namely Ellinikon (Athens), Elefsis, Megara, Heraklion, Chania and Patras, based on real data obtained from meteorological observations in these sites and on computations related with their geographic position. In addition to that, a comparison is presented of the atmospheric stability classes produced with online measurements for the Ellinikon (Athens) site with significant coincidence in the results.

These calculated values of the meteorological parameters (particularly of atmospheric stability) are most appropriate for uncertainty calculations in quantified risk assessments (QRAs) of hazardous installations sited in the above-mentioned areas, especially when risk and safety-related decisions need to be taken. Consequent results obtained with these parameters are more realistic compared to the “classical” assumption of D5/F2, which leads to significant diversification in the estimation of risk.  相似文献   

110.
Composts fractions were extracted by water from composts at the beginning and at the end of the composting process. These water extracts were characterized by elementary analysis and spectroscopies, and then, tested for their capacity to photosensitize the degradation of three aromatic compounds: Irgarol, fenuron, and 2,4,6-trimethylphenol. In solar light, the water extracts (25 mg/l) were found to completely degrade 2,4,6-trimethylphenol after 24 h, and afford a transformation of fenuron and Irgarol of 25% and 18%, respectively.An erratum to this article can be found at  相似文献   
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