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961.
The coastal landscapes in southwestern Korea include a diverse array of tidal wetlands and salt marshes. These coastal zones
link the ecological functions of marine tidal wetlands and freshwater ecosystems with terrestrial ecosystems. They are rich
in biological diversity and play important roles in sustaining ecological health and processing environmental pollutants.
Korean tidal wetlands are particularly important as nurseries for economically important fishes and habitats for migratory
birds. Diking, draining, tourism, and conversion to agricultural and urban uses have adversely affected Korean tidal wetlands.
Recent large development projects have contributed to further losses. Environmental impact assessments conducted for projects
affecting tidal wetlands and their surrounding landscapes should be customized for application to these special settings.
Adequate environmental impact assessments will include classification of hydrogeomorphic units and consideration of their
responses to biological and environmental stressors. As is true worldwide, Korean laws and regulations are changing to be
more favorable to the conservation and protection of tidal wetlands. More public education needs to be done at the local level
to build support for tidal wetland conservation. Some key public education points include the role of tidal wetlands in maintaining
healthy fish populations and reducing impacts of nonpoint source pollution. There is also a need to develop procedures for
integrating economic and environmental objectives within the overall context of sustainable management and land uses. 相似文献
962.
Richard M. Ryan Netta Weinstein Jessey Bernstein Kirk Warren Brown Louis Mistretta Marylène Gagné 《Journal of environmental psychology》2010
Five studies utilizing survey, experimental, and diary methods assessed the effects of being outdoors on subjective vitality. In Study 1, we used a vignette method to examine whether being outdoors was associated with vitality, above and beyond the influences of physical activity and social interactions. Study 2 explored the effects of being outdoors on vitality through an experimental design contrasting indoor and outdoor walks. In Study 3, participants were exposed to photographic scenes of either nature or buildings. Results showed that only the nature scenes enhanced subjective vitality. Studies 4 and 5 used a diary methodology to examine within-person variations in subjective energy as a function of being outdoors, again controlling for physical and social activity. Being outdoors was associated with greater vitality, a relation that was mediated by the presence of natural elements. Limitations of these studies are discussed, as well as their implications for research on energy and vitalization. 相似文献
963.
Analysis of arable land loss and its impact on rural sustainability in Southern Jiangsu Province of China 总被引:2,自引:0,他引:2
Rapid urbanization and industrialization in southern Jiangsu Province have consumed a huge amount of arable land. Through comparative analysis of land cover maps derived from TM images in 1990, 2000 and 2006, we identified the trend of arable land loss. It is found that most arable land is lost to urbanization and rural settlements development. Urban settlements, rural settlements, and industrial park-mine-transport land increased, respectively, by 87 997 ha (174.65%), 81 041 ha (104.52%), and 12 692 ha (397.99%) from 1990 to 2006. Most of the source (e.g., change from) land covers are rice paddy fields and dryland. These two covers contributed to newly urbanized areas by 37.12% and 73.52% during 1990–2000, and 46.39% and 38.86% during 2000–2006. However, the loss of arable land is weakly correlated with ecological service value, per capita net income of farmers, but positively with grain yield for some counties. Most areas in the study site have a low arable land depletion rate and a high potential for sustainable development. More attention should be directed at those counties that have a high depletion rate but a low potential for sustainable development. Rural settlements should be controlled and rationalized through legislative measures to achieve harmonious development between urban and rural areas, and sustainable development for rural areas with a minimal impact on the ecoenvironment. 相似文献
964.
Victor Darde Kaj Thomsen Willy J.M. van Well Erling H. Stenby 《International Journal of Greenhouse Gas Control》2010,4(2):131-136
The chilled ammonia process absorbs the CO2 at low temperature (2–10 °C). The heat of absorption of carbon dioxide by ammonia is significantly lower than for amines. In addition, degradation problems can be avoided and a high carbon dioxide capacity is achieved. Hence, this process shows good perspectives for decreasing the heat requirement. However, a scientific understanding of the processes is required. The thermodynamic properties of the NH3–CO2–H2O system were described using the extended UNIQUAC electrolyte model developed by Thomsen and Rasmussen in a temperature range from 0 to 110 °C and pressure up to 100 bars. The results show that solid phases consisting of ammonium carbonate and bicarbonate are formed in the absorber. The heat requirements in the absorber and in the desorber have been studied. The enthalpy calculations show that a heat requirement for the desorber lower than 2 GJ/ton CO2 can be reached. 相似文献
965.
966.
Romeu Casarano Denise F. S. Petri Michael Jaffe Luiz H. Catalani 《Journal of Polymers and the Environment》2010,18(1):33-44
A new aliphatic block copolyester was synthesized in bulk from transesterification techniques between poly((R)-3-hydroxybutyrate)
(PHB) and poly(isosorbide succinate) (PIS). Additionally, other two block copolyesters were synthesized in bulk either from
transesterification reactions involving PHB and poly(l-lactide) (PLLA) or from ring-opening copolymerization of l-lactide and hydroxyl-terminated PHB, as result of a previous transesterification reactions with isosorbide. Two-component
blends of PHB and PIS or PLLA were also prepared as comparative systems. SEC, MALDI-TOF mass spectrometry (MALDI-TOFMS), 1H and 13C NMR spectroscopy, WAXD, solubility tests, and TG thermal analysis were used for characterization. The block copolymer structures
of the products were evidenced by MALDI-TOFMS, 13C NMR, and WAXD data. The block copolymers and the corresponding binary blends presented different solubility properties,
as revealed by solubility tests. Although the incorporation of PIS sequences into PHB main backbone did not enhance the thermal
stability of the product, it reduced its crystallinity, which could be advantageous for faster biodegradation rate. These
products, composed of PHB and PIS or PLLA sequences, are an interesting alternative in biomedical applications. 相似文献
967.
P. Noorunnisa Khanam H. P. S. Abdul Khalil M. Jawaid G. Ramachandra Reddy C. Surya Narayana S. Venkata Naidu 《Journal of Polymers and the Environment》2010,18(4):727-733
The variation of mechanical properties such as tensile and flexural properties of randomly oriented unsaturated polyester
based sisal/carbon fibre reinforced hybrid composites with different fibre weight ratios have been studied. The chemical resistance
test of these hybrid composites to various solvents, acids and alkalies were studied. The effect of NaOH treatment of sisal
fibres on the tensile, flexural and chemical resistance properties of these sisal/carbon hybrid composites has also been studied.
The hybrid composites showed an increase in tensile and flexural properties with increase in the carbon fibre loading. The
tensile properties and flexural properties of these hybrid composites have been found to be higher than that of the matrix.
Significant improvement in tensile properties and flexural properties of the sisal/carbon hybrid composites has been observed
by alkali treatment. The chemical resistance test results showed that these untreated and alkali treated hybrid composites
are résistance to all chemicals except carbon tetra chloride. Hand lay-up technique was used for making the composites and
tests are carried out by using ASTM methods. 相似文献
968.
Richard C. Warner Carmen T. Agouridis Page T. Vingralek Alex W. Fogle 《Journal of the American Water Resources Association》2010,46(4):724-732
Warner, Richard C., Carmen T. Agouridis, Page T. Vingralek, and Alex W. Fogle, 2010. Reclaimed Mineland Curve Number Response to Temporal Distribution of Rainfall. Journal of the American Water Resources Association (JAWRA) 46(4): 724-732. DOI: 10.1111/j.1752-1688.2010.00444.x Abstract: The curve number (CN) method is a common technique to estimate runoff volume, and it is widely used in coal mining operations such as those in the Appalachian region of Kentucky. However, very little CN data are available for watersheds disturbed by surface mining and then reclaimed using traditional techniques. Furthermore, as the CN method does not readily account for variations in infiltration rates due to varying rainfall distributions, the selection of a single CN value to encompass all temporal rainfall distributions could lead engineers to substantially under- or over-size water detention structures used in mining operations or other land uses such as development. Using rainfall and runoff data from a surface coal mine located in the Cumberland Plateau of eastern Kentucky, CNs were computed for conventionally reclaimed lands. The effects of temporal rainfall distributions on CNs was also examined by classifying storms as intense, steady, multi-interval intense, or multi-interval steady. Results indicate that CNs for such reclaimed lands ranged from 62 to 94 with a mean value of 85. Temporal rainfall distributions were also shown to significantly affect CN values with intense storms having significantly higher CNs than multi-interval storms. These results indicate that a period of recovery is present between rainfall bursts of a multi-interval storm that allows depressional storage and infiltration rates to rebound. 相似文献
969.
É. Joó H. Van Langenhove M. Šimpraga K. Steppe C. Amelynck N. Schoon J.-F. Müller J. Dewulf 《Atmospheric environment (Oxford, England : 1994)》2010,44(2):227-234
Volatile organic compounds (VOCs) have been the focus of interest to understand atmospheric processes and their consequences in formation of ozone or aerosol particles; therefore, VOCs contribute to climate change. In this study, biogenic VOCs (BVOCs) emitted from Fagus sylvatica L. trees were measured in a dynamic enclosure system. In total 18 compounds were identified: 11 monoterpenes (MT), an oxygenated MT, a homoterpene (C14H18), 3 sesquiterpenes (SQT), isoprene and methyl salicylate. The frequency distribution of the compounds was tested to determine a relation with the presence of the aphid Phyllaphis fagi L. It was found that linalool, (E)-β-ocimene, α-farnesene and a homoterpene identified as (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), were present in significantly more samples when infection was present on the trees. The observed emission spectrum from F. sylvatica L. shifted from MT to linalool, α-farnesene, (E)-β-ocimene and DMNT due to the aphid infection. Sabinene was quantitatively the most prevalent compound in both, non-infected and infected samples. In the presence of aphids α-farnesene and linalool became the second and third most important BVOC emitted. According to our investigation, the emission fingerprint is expected to be more complex than commonly presumed. 相似文献
970.
Chuan-Yao Lin C.-C. Chang C.Y. Chan C.H. Kuo W.-C. Chen D. Allen Chu Shaw C. Liu 《Atmospheric environment (Oxford, England : 1994)》2010,44(2):182-193
To quantify the possible sources of the high ambient ozone concentration in the low troposphere over Taiwan, ozone sounding data from a two-year intensive field measurement program conducted in April and early May of 2004 and 2005 in northern Taiwan has been examined. We found that the vertical ozone distributions and occurrence of enhanced ozone in the lower troposphere (below 6 km) mainly resulted from (1)Type NE: the long-range transport of ozone controlled by the prevailing northeasterly winds below 2 km, (2)Type LO: the local photochemical ozone production process, and (3)Type SW: the strong southwest/westerly winds aloft (2–6 km). In the boundary layer (BL), where Asian continental outflow prevails, the average profile for type NE is characterized by a peak ozone concentration of nearly 65 ppb at about 1500 m altitude. For type LO, high ozone concentration with an average ozone concentration greater than 80 ppb was also found in the BL in the case of stagnant atmospheric and sunny weather conditions dominated. For type SW, significant ozone enhancement with average ozone concentration of 70–85 ppb was found at around 4 km altitude. It is about 10 ppb greater than that of the types NE and LO at the same troposphere layer owing to the contribution of the biomass burning over Indochina. Due to Taiwan's unique geographic location, the complex interaction of these ozone features in the BL and aloft, especially features associated with northeasterly and south/southwesterly winds, have resulted in complex characteristics of ozone distributions in the lower troposphere over northern Taiwan. 相似文献