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91.
This paper presents the assessment of gaseous and particulate emissions from thermal power plants operating on different combustion technologies. Four thermal power plants operating on heavy furnace oil were selected for the study, among which three were based on diesel engine technology, while the fourth plant was based on oil-fired steam turbine technology. The stack emissions were monitored for critical air pollutants carbon monoxide, carbon dioxide, oxides of nitrogen, sulfur dioxide, particulate matter, lead, and mercury. The pollutant emissions were measured at optimum load conditions for a period of 6 months with an interval of 1 month. The results of stack emissions were compared with National Environmental Quality Standards of Pakistan and World Bank guidelines for thermal power plants, and few parameters were found higher than the permissible limits of emissions. It was observed that the emissions carbon monoxide, oxides of nitrogen, and particulate matters from diesel engine-based power plants were comparatively higher than the turbine-based power plants. The emissions of sulfur dioxide were high in all the plants, even the plants with different technologies, which was mainly due to high sulfur contents in fuel.  相似文献   
92.
Director of environmental studies at the Indira Gandhi Centre for Human Ecology, Environmental and Population Studies at the University of Rajasthan. This paper describes the biodiversity in the north-western Indian State of Rajasthan, its relationship with the environment and the existing human and livestock populations. As the biodiversity is depleting in this area due to zoogenic and anthropogenic reasons, certain pragmatic conservation strategies are advocated. The north-western part of India is occupied by a desert ecosystem, the Thar Desert. Animal husbandry is the major livelihood in the region, followed by agriculture. The vegetation, which is predominantly xerophytic and quite sparse, occurs in great variety. Six hundred and eighty-two plant species and 390 animal species have been identified from the Thar Desert. Many plant and animal species have become endangered due to zoogenic and anthropogenic activities. Plants such as Calligonum polygonoides, Tecomella undulata and Prosopis cineraria urgently require conservation.  相似文献   
93.
ABSTRACT: In projects involving ground water problems, dependence on the mathematical modeling of the ground water flow phenomena is inescapable. At present, two dimensional flow models, which require tremendous amounts of computer time and storage, are generally used. When such bulky models are used for planning purposes, the two requirements (computer time and storage) can severely limit the number of alternatives that can be considered. A simple quantity and quality simulation model is developed here which requires considerably less computer time and storage and gives reasonably accurate results. The model was applied to simulate a ground water basin in San Luis Rey River in Southern California. The results were compared with those obtained by a USGS model. It was found that the simple model gave results which were consistentaly within five percent of the USGS model results, while the requirements on computer time and storage were drastically reduced.  相似文献   
94.
The International Natural Rubber Agreement (INRA) 1979 is the first, and so far the only, commodity agreement to emerge from the negotiations under the Integrated Programme for Commodities (IPC). The agreement is examined in the context of the issues relating to international stock and as an indicator for future development. The author concludes that while the principle of joint responsibility for financing international stock has been for the first time accepted in INRA, this has been achieved at the cost of reducing the scope of the regulatory mechanism, and that the single-instrument pattern that the agreement has adopted may not be suitable or acceptable in other commodities.  相似文献   
95.
Dermal treatments with crufomate 100 or 50 mg/kg or crufomate vehicle 100 mg/kg were applied to mice either on days 35 and 21 before mating or on days 70, 56, 35, and 21 before mating. Two, but not four dermal treatments, with both doses of crufomate reduced the mating reponse and conception rate in mice. The mice either did not produce a litter or the litter died before the age of 7 days. Four treatments with crufomate 100 mg/kg, but not with 50 mg/kg, reduced the weaning weight of progeny weaned at the age of 21 days. The vehicle had no effects on reproduction and increased the weights at maturity of female and male progeny of mice given two and four treatments, respectively.  相似文献   
96.
Stored wheat treated with radiolabelled pirimiphos-methyl (0-2-diethyl-amino-6-methyl-pyrimidin-4-yl 0,0-dimethyl phosphorothioate) formed bound (nonextractable) 14C residues. Supercritical fluid extraction, gas chromatography and mass spectrometric techniques were used to identify and quantitate the 14C bound residues in wheat grains. The amount of bound 14C residues present after 28 weeks of storage was about 9.9% of the applied radioactivity. Pirimiphos-methyl accounted for 80% of the bound residue. Grain-bound residues were fed to rats for 5 days. After a total period of 8 days a substantially large percentage of the administered bound 14C residues (72.9%) was eliminated in urine while feces contained only 17.9%. Bound pirimiphos-methyl in wheat grain was metabolized in rats by processes involving hydrolysis, N-dealkylation and 0-demethylation. The results indicate that wheat-bound residues of pirimiphos-methyl are highly bioavailable to the rat and may possess a toxicological potential as manifested by a significant reduction in body weight gain.  相似文献   
97.
The author examines the provisions of the New International Economic Order (NIEO), and maintains that with or without a Common Fund, International Commodity Agreements are, and will remain, a recognized instrument for achieving the objectives of the NIEO. Because of various factors conducive to effective organization — including the convergence of interests among producing and consuming countries — the International Tin Agreement (ITA) has made some useful contributions. But wider objectives can only be achieved by appropriate structural reforms in commodity organization.  相似文献   
98.
Khan KS  Joergensen RG 《Chemosphere》2006,65(6):981-987
Two incubation experiments were conducted to evaluate differences in the microbial use of non-contaminated and heavy metal contaminated nettle (Urtica dioica L.) shoot residues in three soils subjected to heavy metal pollution (Zn, Pb, Cu, and Cd) by river sediments. The microbial use of shoot residues was monitored by changes in microbial biomass C, biomass N, biomass P, ergosterol, N mineralisation, CO(2) production and O(2) consumption rates. Microbial biomass C, N, and P were estimated by fumigation extraction. In the non-amended soils, the mean microbial biomass C to soil organic C ratio decreased from 2.3% in the low metal soil to 1.1% in the high metal soils. In the 42-d incubation experiment, the addition of 2% nettle residues resulted in markedly increased contents of microbial biomass P (+240%), biomass C (+270%), biomass N (+310%), and ergosterol (+360%). The relative increase in the four microbial properties was similar for the three soils and did not show any clear heavy metal effect. The contents of microbial biomass C, N and P and ergosterol contents declined approximately by 30% during the incubation as in the non-amended soils. The ratios microbial biomass C to N, microbial biomass C to P, and ergosterol to microbial biomass C remained constant at 5.2, 26, and 0.5%, respectively. In the 6-d incubation experiment, the respiratory quotient CO(2)/O(2) increased from 0.74 in the low metal soil to 1.58 in the high metal soil in the non-amended soils. In the treatments amended with 4% nettle residues, the respiratory quotient was constant at 1.13, without any effects of the three soils or the two nettle treatments. Contaminated nettle residues led generally to significantly lower N mineralisation, CO(2) production and O(2) consumption rates than non-contaminated nettle residues. However, the absolute differences were small.  相似文献   
99.
The effect of copper on adsorption of p-nitrophenol on two typical Chinese soils was investigated using a batch-equilibration method. Adsorption experiments were carried out when both copper and p-nitrophenol were adsorbed simultaneously, and when copper was previously adsorbed on soils. It was observed that adsorption of p-nitrophenol decreased with increasing copper concentrations thereby indicating a competition between copper and p-nitrophenol for occupying the adsorption sites on soils. Moisture increased the hydrated sphere and the acidity of water surrounding the cation, which further reduced the adsorption of p-nitrophenol. Fourier transform infrared spectroscopy study provided the direct evidence for the coordination of p-nitrophenol sorbed by soils with metal cation in n-hexane system. It was observed that the perturbations included a red shift of the nu(asym) (NO) band, a concomitant blue-shift of the nu(sym) (NO) band and a blue-shift of C-N band when compared with the infrared spectra obtained from water solution.  相似文献   
100.
Effective environmental management through life cycle assessment   总被引:6,自引:0,他引:6  
Unplanned and unsustainable development (particularly rapid industrialisation) has placed great pressure in every dimension of the environment (air, water, soil, health, etc.). The resulting disturbance in the natural ecological balance is a serious concern. Sustainable development is the need of the hour; it can only be achieved through effective environmental management. Environmental management will become indispensable in the future as regulatory restrictions tighten and public expectations of environmental performance increase. The day is not far away when a customer will prefer to buy products produced by an environmentally committed organisation. In short, the environmental commitment of an organisation will become a market strategy.

Environmental management is a set of actions based on a structured methodology to ensure that an organisation is committed to the environment and that the production process has minimal/no adverse affect on it. This article emphasises environmental management in the real engineering sense of the term, and discusses how to develop an effective environmental management system through life cycle assessment. It further demonstrates through a real life case study how an industry has achieved landmark success in managing its environment, production, as well as winning the good faith of society.  相似文献   

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