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631.
Geochemistry in the modern soil survey program 总被引:1,自引:0,他引:1
Wilson MA Burt R Indorante SJ Jenkins AB Chiaretti JV Ulmer MG Scheyer JM 《Environmental monitoring and assessment》2008,139(1-3):151-171
Elemental analysis has played an important role in the characterization of soils since inception of the soil survey in the
US. Recent efforts in analysis of trace and major elements (geochemistry) have provided necessary data to soil survey users
in a variety of areas. The first part of this paper provides a brief overview of elemental sources, forms, mobility, and bioavailability;
critical aspects important to users of soil survey geochemical data for appropriate use and interpretations. Examples are
provided based on data gathered as part of the US soil survey program. The second part addresses the organization of sample
collection in soil survey and how soil surveys are ideally suited as a sampling strategy for soil geochemical studies. Geochemistry
is functional in characterization of soil types, determining soil processes, ecological evaluation, or issues related to soil
quality and health, such as evaluating suitability of soils for urban or agricultural land use. Applications of geochemistry
are on-going across the US and are documented herein. This analytical direction of soil survey complements historic efforts
of the National Cooperative Soil Survey Program and addresses the increasing need of soil survey users for data that assists
in understanding the influence of human activities on soil properties. 相似文献
632.
Mohamed H. Mohamed Lee D. Wilson John V. Headley Kerry M. Peru 《Process Safety and Environmental Protection》2008,86(4):237
A nanofiltration strategy for tailing pond waters (TPWs) that utilizes cyclodextrin (CD)-based polymeric materials as supramolecular sorbents is proposed. Naphthenic acids (NAs) from the Athabasca TPWs are investigated as the target sorbate molecules.The sorption properties of several supramolecular porous materials were characterized using equilibrium sorption isotherms in aqueous solution wherein electrospray ionization mass spectrometry was used to monitor the concentration of NAs in aqueous solution. The characterization of the supramolecular sorbents was performed using 13C NMR and IR spectroscopy, while nitrogen porosimetry was used to estimate their surface area and pore structure properties. Independent estimates of surface area were obtained using a chromophore dye adsorption method in aqueous solution.The sorption results for NAs in solution were compared between a commercially available standard; granular activated carbon (GAC) and three types of synthetic materials. The sorption capacities for GAC ranged from 100 to 160 mg NAs/g of material whereas the polymeric materials ranged from 20 to 30 mg NAs/g of material over the experimental conditions investigated. In general, differences in the sorption properties between GAC and the CD-based sorbents were observed and related to differences in the surface areas of the materials and the chemical nature of the sorbents. The CD-based supramolecular materials displayed sorption capacities ranging from 36.2 to 657 m2/g as compared to that for GAC (795 m2/g). 相似文献
633.
Schlindweinn Elizabeth Bianchini Chacon Wilson Daniel Caicedo Koop Betina Luiza de Matos Fonseca Jéssica Monteiro Alcilene Rodrigues Valencia Germán Ayala 《Journal of Polymers and the Environment》2022,30(9):3547-3565
Journal of Polymers and the Environment - Anthocyanins (ACNs) are natural pigments broadly used in the food industry due to their color, antioxidant, and antimicrobial properties, however, these... 相似文献
634.
John R. Post Hillary G. M. Ward Kyle L. Wilson George L. Sterling Ariane Cantin Eric B. Taylor 《Conservation biology》2022,36(3):e13783
Use of extensive but low-resolution abundance data is common in the assessment of species at-risk status based on quantitative decline criteria under International Union for Conservation of Nature (IUCN) and national endangered species legislation. Such data can be problematic for 3 reasons. First, statistical power to reject the null hypothesis of no change is often low because of small sample size and high sampling uncertainty leading to a high frequency of type II errors. Second, range-wide assessments composed of multiple site-specific observations do not effectively weight site-specific trends into global trends. Third, uncertainty in site-specific temporal trends and relative abundance are not propagated at the appropriate spatial scale. A common result is the propensity to underestimate the magnitude of declines and therefore fail to identify the appropriate at-risk status for a species. We used 3 statistical approaches, from simple to more complex, to estimate temporal decline rates for a designatable unit (DU) of rainbow trout in the Athabasca River watershed in western Canada. This DU is considered a native species for purposes of listing because of its genetic composition characterized as >0.95 indigenous origin in the face of continuing introgressive hybridization with introduced populations in the watershed. Analysis of abundance trends from 57 time series with a fixed-effects model identified 33 sites with negative trends, but only 2 were statistically significant. By contrast, a hierarchical linear mixed model weighted by site-specific abundance provided a DU-wide decline estimate of 16.4% per year and a 3-generation decline of 93.2%. A hierarchical Bayesian mixed model yielded a similar 3-generation decline trend of 91.3% and the posterior distribution showed that the estimate had a >99% probability of exceeding thresholds for an endangered listing. We conclude that the Bayesian approach was the most useful because it provided a probabilistic statement of threshold exceedance in support of an at-risk status recommendation. 相似文献
635.
Lichtfouse Eric Morin-Crini Nadia Bradu Corina Boussouga Youssef-Amine Aliaskari Mehran Schfer Andrea Iris Das Soumya Wilson Lee D. Ike Michihiko Inoue Daisuke Kuroda Masashi Don Sbastien Fievet Patrick Crini Grgorio 《Environmental Chemistry Letters》2022,20(3):2019-2041
Environmental Chemistry Letters - Worldwide contamination of waters by metals, metalloids, and organometallic pollutants is a major health issue. In particular, the occurrence of the selenium... 相似文献