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541.
Rajiv Kumar Sharma Pooja Sharma 《Journal of Loss Prevention in the Process Industries》2012,25(6):883-904
The research implications of reliability, availability and maintainability (RAM) aspects of engineering systems in recent years have increased substantially due to rising operation and maintenance costs. To strike a balance between the two the paper presents a framework which makes use of both qualitative and quantitative techniques to optimize RAM and cost decisions in a process plant. In the quantitative analysis, the imprecise and vague information regarding the system failure behavior is quantified by using the principles of fuzzy mathematics in terms of fuzzy and crisp values. Further, to manage the system reliability for best economic performance a resource optimization model based on multi-stage decision making (MSDM) has been proposed. The model makes use of crisp output values of unit's reliability along with relevant system information (number of components, manpower, cost ranges). In the qualitative analysis the in-depth analysis of the system is carried out using Root Cause analysis (RCA) and Failure Mode & Effects Analysis (FMEA). The ambiguities associated with the traditional FMEA are handled using Fuzzy Decision Making System (FDMS) and Grey Relation Analysis (GRA). The suggested framework has been illustrated with the help of a case. 相似文献
542.
Water quality index and suitability assessment of urban ground water of Hisar and Panipat in Haryana
Kaushik A Kumar K Kanchan Taruna Sharma HR 《Journal of environmental biology / Academy of Environmental Biology, India》2002,23(3):325-333
Ground water quality in two well-developed cities of Haryana, viz. Hisar and Panipat was assessed for drinking purpose based on water quality parameters like pH, EC, turbidity, TDS, alkalinity, total hardness, calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), chloride (Cl), nitrate (NO3), phosphate (PO4), sulphate (SO4) and fluoride (F) with respect to different land-use areas viz. residential, industrial, commercial and agricultural. Water quality index based on 9 parameters showed that at Panipat, underground water in all the land-use zones was fit for consumption (WQI < 50), whereas at Hisar, water in agricultural areas was good in quality, but that in other areas varied in magnitude of pollution (WQI > 50 to 100). 相似文献
543.
Environmental contamination by pesticides has been documented in biotic and abiotic components. These persistent organic pollutants are lipid soluble, nonbiodegradable, and endocrine disrupters. The present study was therefore planned to determine whether the levels of these pesticides like DDT and its metabolites DDD and DDE, dieldrin, heptachlor, and HCH and its isomers (alpha, beta, and gamma) were higher in blood of breast cancer patients when compared with normal women who did not suffer from major diseases like blood pressure, tuberculosis, diabetes, thyroid dysfunction, arthritis, cancer, etc. and had not undergone any major surgery. The results indicated that organochlorine pesticides taken for analysis were found significantly high in breast cancer patients irrespective of age, diet, and geographic distribution. 相似文献
544.
Gupta K Sharma A 《Journal of environmental biology / Academy of Environmental Biology, India》2005,26(2):205-211
Various pollution indicators of stream Ban-Ganga have been identified on the basis of presence/absence/numerical abundance at various stations. They have been categorized as pollution tolerant, facultative and pollution intolerant groups in relation with the water quality at different stations of stream. 相似文献
545.
Tripathi G Gaur A Sharma BM 《Journal of environmental biology / Academy of Environmental Biology, India》2005,26(2):265-268
Impact of temperature related seasonal changes in density of Golgi complex were studied in brain, heart and intestine of the freshwater catfish, Clarias batrachus (Linnaeus). The density of Golgi complex was more in these organs of the fish acclimatized to a lower temperature (20 degrees C) than that to a higher temperature (29 degrees C). This suggests that lower temperature induces secretory activity in cells to cope up with the changes in surrounding environment. It could be a kind of histophysiological adaptation in poikilothermic animal. 相似文献
546.
Soil, water and nutrient conservation in mountain farming systems: case-study from the Sikkim Himalaya 总被引:3,自引:0,他引:3
The Khanikhola watershed in Sikkim is agrarian with about 50% area under rain-fed agriculture representing the conditions of the middle mountains all over the Himalaya. The study was conducted to assess overland flow, soil loss and subsequent nutrient losses from different land uses in the watershed, and identify biotechnological inputs for management of mountain farming systems. Overland flow, soil and nutrient losses were very high from open agricultural (cropped) fields compared to other land uses, and more than 72% of nutrient losses were attributable to agriculture land use. Forests and large cardamom agroforestry conserved more soil compared to other land uses. Interventions, like cultivation of broom grass upon terrace risers, N2-fixing Albizia trees for maintenance of soil fertility and plantation of horticulture trees, have reduced the soil loss (by 22%). Soil and water conservation values (> 80%) of both large cardamom and broom grass were higher compared to other crops. Use of N2-fixing Albizia tree in large cardamom agroforestry and croplands contributed to soil fertility, and increased productivity and yield. Bio-composting of farm resources ensured increase in nutrient availability specially phosphorus in cropped areas. Agricultural practices in mountain areas should be strengthened with more agroforestry components, and cash crops like large cardamom and broom grass in agroforestry provide high economic return and are hydroecologically sustainable. 相似文献
547.
548.
549.
Asbjørn Aaheim Ranjith Gopalakrishnan Rajiv Kumar Chaturvedi N. H. Ravindranath Anitha D. Sagadevan Nitasha Sharma Taoyuan Wei 《Mitigation and Adaptation Strategies for Global Change》2011,16(2):229-245
We examine the potential for adaptation to climate change in Indian forests, and derive the macroeconomic implications of
forest impacts and adaptation in India. The study is conducted by integrating results from the dynamic global vegetation model
IBIS and the computable general equilibrium model GRACE-IN, which estimates macroeconomic implications for six zones of India.
By comparing a reference scenario without climate change with a climate impact scenario based on the IPCC A2-scenario, we
find major variations in the pattern of change across zones. Biomass stock increases in all zones but the Central zone. The
increase in biomass growth is smaller, and declines in one more zone, South zone, despite higher stock. In the four zones
with increases in biomass growth, harvest increases by only approximately 1/3 of the change in biomass growth. This is due
to two market effects of increased biomass growth. One is that an increase in biomass growth encourages more harvest given
other things being equal. The other is that more harvest leads to higher supply of timber, which lowers market prices. As
a result, also the rent on forested land decreases. The lower prices and rent discourage more harvest even though they may
induce higher demand, which increases the pressure on harvest. In a less perfect world than the model describes these two
effects may contribute to an increase in the risk of deforestation because of higher biomass growth. Furthermore, higher harvest
demands more labor and capital input in the forestry sector. Given total supply of labor and capital, this increases the cost
of production in all the other sectors, although very little indeed. Forestry dependent communities with declining biomass
growth may, however, experience local unemployment as a result. 相似文献
550.