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701.
Yoganandan N Pintar FA Gennarelli TA Martin PG Ridella SA 《Traffic injury prevention》2008,9(2):162-167
A majority of laboratory-driven side-impact injury assessments are conducted using postmortem human subjects (PMHS) under the pure lateral mode. Because real-world injuries occur under pure and oblique modes, this study was designed to determine chest deflections and injuries using PMHS under the latter mode. Anthropometrical data were obtained and x-rays were taken. Specimens were seated on a sled and lateral impact acceleration corresponding to a change in velocity of 24 km/h was applied such that the vector was at an angle of 20 or 30 degrees. Chestbands were fixed at the level of the axilla (upper), xyphoid process (middle), and tenth rib (lower) location. Deflection contours as a function of time at the levels of the axilla and mid-sternum, representing the thorax, and at the tenth rib level, representing the abdomen, were evaluated for peak magnitudes. All data were normalized using mass-scaling procedures. Injuries were identified following the test at autopsy. Trauma graded according to the Abbreviated Injury Score, 1990 version, indicated primarily unilateral rib fractures and soft tissue abnormalities such as lung contusion and diaphragm laceration occurred. Mean peak deflections at the upper, middle, and lower levels of the chest for the 30-degree tests were 96.2, 78.5, and 76.8 mm. For the 20-degree tests, these magnitudes were 77.5, 89.9, and 73.6 mm. Statistical analysis indicated no significant (p > 0.05) differences in peak chest deflections at all levels between the two obliquities although the metric was significantly greater in oblique than pure lateral impacts at the mid and lower thoracic levels. These response data are valuable in oblique lateral impact assessments. 相似文献
702.
703.
A Quantitative Analysis of Biodiversity and the Recreational Value of Potential National Parks in Denmark 总被引:1,自引:0,他引:1
Denmark has committed itself to the European 2010 target to halt the loss of biodiversity. Currently, Denmark is in the process
of designating larger areas as national parks, and 7 areas (of a possible 32 larger nature areas) have been selected for pilot
projects to test the feasibility of establishing national parks. In this article, we first evaluate the effectiveness of the
a priori network of national parks proposed through expert and political consensus versus a network chosen specifically for
biodiversity through quantitative analysis. Second, we analyze the potential synergy between preserving biodiversity in terms
of species representation and recreational values in selecting a network of national parks. We use the actual distribution
of 973 species within these 32 areas and 4 quantitative measures of recreational value. Our results show that the 7 pilot
project areas are not significantly more effective in representing species than expected by chance and that considerably more
efficient networks can be selected. Moreover, it is possible to select more-effective networks of areas that combine high
representation of species with high ranking in terms of recreational values. Therefore, our findings suggest possible synergies
between outdoor recreation and biodiversity conservation when selecting networks of national parks. Overall, this Danish case
illustrates that data-driven analysis can not only provide valuable information to guide the decision-making process of designating
national parks, but it can also be a means to identify solutions that simultaneously fulfill several goals (biodiversity preservation
and recreational values). 相似文献
704.
Michael J. Mason Jeremy Mennis J. Douglas Coatsworth Thomas Valente Frank Lawrence Patricia Pate 《Journal of environmental psychology》2009
Geographic and substance use data were collected from 301 urban adolescents to compare the perceived and observed risk and safety associated with their home and activity space locations (routine locations). The geographic characteristics of the neighborhood surrounding each location was summarized according to features theorized to be risky, such as criminal activity and alcohol sales, and features theorized to be safe, such as recreation centers and churches. Data on socioeconomic status, derived from U.S. Bureau of the Census data, were also used to characterize locations. Adolescents' homes were typically perceived as safe despite observed measures of risk such as density of crimes and proximity to alcohol outlets. This held for both substance users and non-users. Differences in geographic characteristics for safe and risky activity spaces were observed for both substance users and non-users, with non-users appearing to be more sensitive to the presence of risky characteristics in the environment than substance users. Results highlight the need and provide a methodology to collect fine-grained activity space data instead of relying only on home residence when attempting to represent place and health behaviors with urban youth. 相似文献
705.
Gallagher FJ Pechmann I Bogden JD Grabosky J Weis P 《Environmental pollution (Barking, Essex : 1987)》2008,153(2):351-361
Anthropogenic sources of toxic elements have had serious ecological and human health impacts. Analysis of the soil samples from a brownfield within Liberty State Park, Jersey City, NJ, USA, showed that arsenic, chromium, lead, zinc and vanadium exist at concentrations above those considered ambient for the area. Accumulation and translocation features were characterized for the dominant plant species of four vegetative assemblages. The trees Betula populifolia and Populus deltoides were found to be accumulating Zn in leaf tissue at extremely high levels. B. populifolia, P. deltoides and Rhus copallinum accumulated Cr primarily in the root tissue. A comparison of soil metal maps and vegetative assemblage maps indicates that areas of increasing total soil metal load were dominated by successional northern hardwoods while semi-emergent marshes consisting mostly of endemic species were restricted primarily to areas of low soil metal load. 相似文献
706.
Vulnerability and adaptation of European farmers: a multi-level analysis of yield and income responses to climate variability 总被引:6,自引:3,他引:3
Pytrik Reidsma Frank Ewert Alfons Oude Lansink Rik Leemans 《Regional Environmental Change》2009,9(1):25-40
Climate change will affect crop yields and consequently farmers’ income. The underlying relationships are not well understood,
particularly the importance of crop management and related factors at the farm and regional level. We analyze the impacts
of trends and variability in climatic conditions from 1990 to 2003 on trends and variability in yields of five crops and farmers’
income at farm type and regional level in Europe considering farm characteristics and other factors. While Mediterranean regions
are often characterized as most vulnerable to climate change, our data suggest effective adaptation to variable and changing
conditions in these regions largely attributable to the characteristic farm types in these regions. We conclude that for projections
of climate change impacts on agriculture, farm characteristics influencing management and adaptation should be considered,
as they largely influence the potential impacts. 相似文献
707.
Hang Xiao Hayley Hung Ying Duan Lei Frank Wania 《Atmospheric environment (Oxford, England : 1994)》2009,43(15):2401-2409
At locations without access to the electrical grid, a flow-through sampler (FTS) collects large volumes of air for the analysis of semi-volatile organic compounds (SVOCs). To test its performance under field conditions, an FTS and a traditional pumped high volume air sampler, both using polyurethane foam (PUF) as sampling medium, were co-deployed at the campus of the University of Toronto Scarborough from August 2006 to June 2007. Polybrominated diphenyl ethers (PBDEs) and various pesticides were quantified in the samples taken by both samplers to test the FTS's applicability to relatively non-volatile and slightly polar SVOCs. Air concentrations in samples taken with the FTS over five 2-week periods compare favourably with the average of the concentrations in several 24-h active high volume samples taken during the same period. In particular, time trends, temperature dependence relationships, and isomer ratios show a reasonable agreement between the two sampling techniques. An empirical linear solvation energy relationship for predicting the apparent theoretical plate number of the PUF assembly used in the FTS illustrates the effect of chemical properties, as well as temperature and wind speed, on sampling efficiency. In the absence of electrical power, the FTS can collect SVOCs from large air volumes as reliably and quantitatively as traditional HiVol samplers, although without separating gas and particle phase. 相似文献
708.
Estrogens-sulphates such as 17beta-estradiol-3-sulphate and estrone-3-sulphate are excreted by livestock in the urine. These conjugates are precursors to the free counterparts 17beta-estradiol and estrone, which are endocrine disrupting chemicals. In this study microcosm laboratory experiments were conducted in three pasture soils from New Zealand to study the aerobic degradation and metabolite formation kinetics of 17beta-estradiol-3-sulphate at three different incubation temperatures. The degradation of 17beta-estradiol-3-sulphate followed a first-order kinetic and the temperature dependence of the rate constants was sufficiently described by the Arrhenius equation. Degradation was different between the three investigated soils and the rate constants across the soils were significantly correlated to the arylsulphatase activity at 7.5 and 15 degrees C. Estrone-3-sulphate and 17beta-estradiol were identified as primary metabolites and estrone as a secondary metabolite. Results suggest arylsulphatase activity originating from soil microbial biomass is the main driver for the degradation of 17beta-estradiol-3-sulphate. 相似文献
709.
Effect of phosphogypsum and dicyandiamide as additives on NH3, N2O and CH4 emissions during composting 总被引:1,自引:0,他引:1
Yiming Luo Guoxue Li Wenhai Luo Frank Schuchardt Tao Jiang Degang Xu 《环境科学学报(英文版)》2013,25(7):1338-1345
A laboratory scale experiment of composting in a forced aeration system using pig manure with cornstalks was carried out to investigate the effects of both phosphogypsum and dicyandiamide (DCD, C2H4N4) as additives on gaseous emissions and compost quality. Besides a control, there were three amended treatments with different amounts of additives. The results indicated that the phosphogypsum addition at the rate of 10% of mixture dry weight decreased NH3 and CH4 emissions significantly during composting. The addition of DCD at the rate of 0.2% of mixture dry weight together with 10% of phosphogypsum further reduced the N2O emission by affecting the nitrification process. Reducing the phosphogypsum addition to 5% in the presence of 0.2% DCD moderately increased the NH3 emissions but not N2O emission. The additives increased the ammonium content and electrical conductivity significantly in the final compost. No adverse effect on organic matter degradation or the germination index of the compost was found in the amended treatments. It was recommended that phosphogypsum and DCD could be used in composting for the purpose of reducing NH3, CH4 and N2O emissions. Optimal conditions and dose of DCD additive during composting should be determined with different materials and composting systems in further study. 相似文献
710.
Perfluorooctanoic acid and perfluorooctane sulfonate in the sediment of the Roter Main river, Bayreuth, Germany 总被引:2,自引:0,他引:2
Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are widely distributed in aquatic ecosystems. Their sources are known but few studies about their accumulation potential in river sediments exist. The aim of this study is to assess the concentrations of PFOA and PFOS in sediments in relation to their levels in river water receiving effluent from a waste water treatment plant (WWTP). PFOS accumulates by a factor of about 40 relative to river water, PFOA only up to threefold. In contrast to previous suggestions, in this case the enrichment on sediment is not correlated to the total organic carbon contents. 相似文献