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191.
192.
For more than two decades a number of frameworks for scientific knowledge production are being proposed by science and technology researchers. They all advocate an extended involvement of non-specialists, in particular when it comes to knowledge production applicable to practical societal problems. We look to what extent these new frameworks have taken ground within a particular research community: the ACCENT Network of Excellence which coordinates European atmospheric chemistry and physics research applicable to air pollution and climate change. We did so by stimulating a debate through a “blog”, a survey and in-depth interviews with ACCENT scientists about the interaction between science, policy making and civil society, to which a great deal of ACCENT member contributed in writing or verbally. Most of them had interactions with policy makers and/or the general public, and they generally believe that interactions with spheres other than the scientific are needed. While such interactions give personal insight and satisfaction, they seem to have little impact on the goals and the practice of the scientific work itself. Extended frameworks of science production that go beyond the disciplinary mode seem to emerge at the level of individual scientists, yet they still need to find their way to the level of scientific project management. In this paper we discuss the justifications and barriers to implement a higher degree of extended knowledge integration in applied science projects such as ACCENT. It is felt that the community of atmospheric chemists and physicists is mature for such an implementation and recommendations are given to help and make this happen.  相似文献   
193.
Eighteen representative sites for the Austrian grain-growing and eight for the potato-growing zones (soils and crops) were investigated. On each site, total element contents (B, Ba, Ca, Cd, Co, Cu, Fe, K, Li, Mg, Mn, Mo, Na, P, Sr and Zn) were determined in 4–12 varieties of winter wheat (n = 136), 6 varieties of spring durum wheat (n = 30), 5 varieties of winter durum wheat (n = 15), 7 varieties of rye (n = 49), 5 varieties of spring barley (n = 30) and 5 varieties of potatoes (n = 40). Element accumulations in grain species and potato tubers varied significantly with site conditions, with the main exceptions for B in potatoes and wheat as well as for Zn, Cu and Co in durum wheat. On average, across all investigated sites, differences in varieties occurred concerning the elements Ca, Cd, Ba, Sr and Zn (except Zn in potatoes and winter durum). A rough estimation revealed that an average Austrian consumer of wheat, rye and potatoes meets more than 50% of the needs of daily element intake for K, P and Mg, between 36 and 72% for Fe, Zn and Cu, and more than 100% for Co, Mo and Mn. In particular, the elements Ca and Na have to be added from other sources.  相似文献   
194.
Catalytic oxidation is an air pollution control technique in which volatile organic compounds (VOCs) and vapor-phase air toxics in an air emission stream are oxidized with the help of a catalyst Design of catalytic systems for control of point source emissions is based on stream-specific characteristics and desired control efficiency. This paper discusses the key emission stream characteristics and VOC characteristics that affect the applicability of catalytic oxidation. The application of catalytic oxidation technology to four types of air emission sources is discussed: (1) groundwater stripping operations; (2) graphic arts facilities; (3) flexographic printing plants; and (4) latex monomer production. The characteristics of each of these emissions are discussed along with the catalytic technology used to control these emissions.  相似文献   
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196.
Air pollution abatement has been a constant concern for the ceramic indudry over the last four decades. The multiplicity of materials involved, numbering in the hundreds of fluxes and refractories for the manufacture of many different types of glasses, results in gaseous as well as particulate reaction products. Methods of abatement through various means have been developed and are in use in the United States and world-wide today.  相似文献   
197.
198.
Since primary environmental concept for long storage of nuclear waste involved assessment of water in uranium complexes depending on migration processes, the paper emphasized solid-state matrix-assisted laser desorption/ionization (MALDI) mass spectrometric (MS) and IR spectroscopic determination of UO2(NO3)2·6H2O; UO2(NO3)2·3H2O, α-, β-, and γ-UO3 modifications; UO3·xH2O (x?=?1 or 2); UO3·H2O, described chemically as UO2(OH)2, β- and γ-UO2(OH)2 modifications; and UO4·2H2O, respectively. Advantages and limitation of vibrational spectroscopic approach are discussed, comparing optical spectroscopic data and crystallographic ones. Structural similarities occurred in α–γ modifications of UO3, and UO2(OH)2 compositions are analyzed. Selective speciation achieved by solid-state mass spectrometry is discussed both in terms of its analytical contribution for environmental quality assurance and assessment of radionuclides, and fundamental methodological interest related the mechanistic complex water exchange of UO3·H2O forms in the gas phase. In addition to high selectivity and precision, UV-MALDI-MS, employing an Orbitrap analyzer, was a method that provided fast steps that limited sample pretreatment techniques for direct analysis including imaging. Therefore, random and systematic errors altering metrology and originating from the sample pretreatment stages in the widely implemented analytical protocols for environmental sampling determination of actinides are significantly reduced involving the UV-MALDI-Orbitrap-MS method. The method of quantum chemistry is utilized as well to predict reliably the thermodynamics and nature of U–O bonds in uranium species in gas and condensed phases.  相似文献   
199.
The diamond cartel has remained effective in controlling diamond supplies and prices for a longer period than any other major minerals cartel in the twentieth century. This paper examines the diamond pipeline from mine to the jewellery market. Particular attention is given to the characteristics of diamonds and of the industry structure that make the long-term stability of the cartel possible. The strategies of De Beers Consolidated Diamond Mines in controlling rough gem supplies and prices are examined, and projections are made to 2000. The paper shows that in spite of a projected decrease in the share of total diamond production sold through the De Beers' cartel in the 1990s, the cartel is expected to continue effectively to control supplies and prices.  相似文献   
200.
This article describes the selection and field evaluation of dredging equipment and techniques for removal of highly contaminated sediments from the upper estuary of the Acusbnet River, a portion of the New Bedford Harbor Supetfund Project. Site conditions as related to dredge selection and operation, factors considered in selection of equipment, and various dredge types considered for use are described. Each of the dredge types is ranked according to the following criteria: availability, safety, potential for sediment resuspension, maneuverability, cleanup precision, cost and production, flexibility, required water depth for operation, ability to access the site, and compatibility with disposal options. A field pilot study comparing three dredge types indicated that dredging could be conducted at the site without a significant increase in the contaminant release from the upper estuary to the lower harbor.  相似文献   
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