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101.
Grabens are formed under the influence of extensional forces in a normal fault system. The Gulf of Gökova is an active graben located in SW Turkey. Active grabens such as the Gökova enclose highly faulted rocky coasts. Despite the existence of these rocky coasts, examination of google earth images, field studies, DEM analysis and previous studies in the Gulf of Gökova graben revealed that there could be different types of coasts in the region. In this study the factors causing the occurrence and potential environmental effects of the diverse coast types are evaluated. By using the Fairbridge (2004) coastal classification system, the coast types identified in the Gulf of Gökova graben can be classified as; A. Soft-less consolidated-erodible; A1: relatively Insoluble: detrital and loose beach, A2: soluble: beachrock and eolinite B. hard-cliffed-rocky, B1: longevity of hard-rock coast and B2: fault controlled cliffs. The percentages of these classes generally decreased from B1 (79%), A1 (12.4%), B2 (8.3%) and A2 (0.3%) in the study area. As a result of longshore currents, A1-type coasts usually develop as large plain adjacent streams and also in pocket beaches as narrow-long strips near rocky coasts. A2 type is observed in one location within the Gökova region, possibly due to local environmental conditions. However, B1 type developed in peridotites, cherty limestone and cliffs probably because of the active fault system and where the fault plane cut the coast, B2 type occurred. Possible threats to the Gökova region can be attributed to sea level rise owing to tectonism and global warming. It is anticipated that inundation, coastal erosion and salt water intrusion may also affect it.  相似文献   
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Geochemical study of groundwater from a structurally deformed granitic terrain near Hyderabad (India) was carried out to understand and evaluate the hydrogeochemical processes and quality of groundwater. Several trace elements (Fe, Mn, Be, Al, V, Cr, Co, Ni, Cu, Zn, As, Sr, Mo, Cd, Sb, Ba, Pb, U) along with major ions and minor elements were precisely estimated in shallow and drilled wells to know the suitability of water for drinking and irrigation purposes. Analytical data shows that pH and major ion chemistry in dug wells and bore wells do not vary significantly, while some trace elements (Fe, Mn, Al, Be, Co, Pb, U and Zn) vary in dug wells and bore wells, which can be attributed to differential mineral weathering and dissolution/precipitation reactions along fractures/joints. Although the water is not potable, it was found to be suitable for irrigation with little danger in the development of harmful level of exchangeable sodium. It is inferred that the chemical composition of the groundwater in this region is likely to have its origin from silicate weathering reactions and dissolution/precipitation processes supported by rainfall and groundwater flow.  相似文献   
104.
The acute salinity tolerance of three tropical freshwater cladoceran species, M. macleayi, C. rigaudii and D. brachyurum was determined. The existence of these species represented new records for Trinidad and Tobago, a tropical Caribbean island. It has a large oil based industry, in which, the primary effluent (saline produced water) is discharged directly into many freshwater systems. Cladoceran species are used routinely in temperate regions, to assess the impacts of chemicals and effluents in freshwater systems. However, relatively few studies have assessed the salinity tolerance of these organisms. Test organisms were assayed using seven salinity treatments (0, 1, 3, 5, 10, 15, 20, 25‰) prepared by volumetrically mixing natural filtered seawater with dilution water. C. rigaudii had a 48 h LC50 of 1.6‰, M. macleayi 1.5‰ and D. brachyurum <1‰. The CSmax (critical salinity maximum) for C. rigaudii and M. macleayi was 3‰ after 48 h, compared to 1‰ for D. brachyurum. There was no salinity value at which there was 100% survival. The resulting salinity response curve was a straight line which indicated that each species was intolerant of salt. Consequently, any of these can be considered as a representative freshwater organism for toxicity testing in Trinidad and Tobago.  相似文献   
105.
Nickel oxide nanoparticles decorated carbon nanotube nanocomposites(Ni O·CNT NCs)were prepared in a basic medium by using facile wet-chemical routes. The optical,morphological, and structural properties of Ni O·CNT NCs were characterized using Fourier transformed infra-red(FT-IR), Ultra-violet visible(UV/Vis) spectroscopy, field-emission scanning electron microscopy(FESEM), X-ray energy dispersed spectroscopy(XEDS), X-ray photoelectron spectroscopy(XPS), and powder X-ray diffraction(XRD) methods. Selective4-aminophenol(4-AP) chemical sensor was developed by a flat glassy carbon electrode(GCE, surface area: 0.0316 cm~2) fabricated with a thin-layer of NCs. Electrochemical responses including higher sensitivity, large dynamic range(LDR), limit of detection(LOD), and long-term stability towards 4-AP were obtained using the fabricated chemical sensors. The calibration curve was found linear(R~2= 0.914) over a wide range of 4-AP concentration(0.1 nmol/L–0.1 mol/L). In perspective of slope(2 × 10~(-5)μA/μM), LOD and sensitivity were calculated as 15.0 ± 0.1 pM and ~ 6.33 × 10~(-4)μA/(μM·cm) respectively. The synthesized Ni O·CNT NCs using a wet-chemical method is a significant route for the development of ultrasensitive and selective phenolic sensor based on nano-materials for environmental toxic substances. It is suggested that a pioneer and selective development of 4-AP sensitive sensor using Ni O·CNT NCs by a facile and reliable current vs voltage(I–V)method for the major application of toxic agents in biological, green environmental, and health-care fields in near future.  相似文献   
106.
Regional Environmental Change - The soils of the Mediterranean Basin are the products of soil processes that have been governed by a unique convergence of highly differentiated natural and...  相似文献   
107.
/ This study aims to investigate the ISO 14001 implementation process and its implications for regional environmental management. The region of Central Japan (known as Chubu in Japanese, which literally means center) was chosen for this case study. The study focuses on selected issues such as the: (1) trends and motives of private firms in the implementation of an ISO 14001-based environmental management system (EMS); (2) obstacles during system implementation; (3) role of the system in enhancing environmental performance within the certified organization; and (4) relation between the major stakeholders, local citizens, governments, and firms after adopting the system. To achieve these objectives, a questionnaire survey was mailed to all certified firms in the region. A 58% response was achieved overall. The results show that the main aims behind the adoption of ISO 14001 by firms in the Chubu region are to improve the environmental aspects within the enterprises and to enhance the employees' environmental awareness and capacity. The results have also shown that the ISO 14001-based EMS has had a great effect on a firm's environmental status as certified firms have claimed that natural resources such as fuel, water, and paper consumption have been more efficiently managed after adopting the system. Implementation of the system causes the firms to consider the role of the local people and the government in more effectively involving the local people in the firm's daily environmental activities. It also helps to enhance the environmental awareness among the local people. Adopting the system also promotes a better relation within the enterprises affiliated to the same group, such as more attention given by the parent firms (head offices) towards other firms working for the same group, or branches-mainly small and medium sized enterprises (SMEs)-in the field of EMS. Finally, the results show that firms give serious consideration to their final products' impacts on the environment. In other words, attention is given to life cycle analysis (LCA) among certified firms.  相似文献   
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109.
Environmental Science and Pollution Research - The agricultural waste of orange peels (OPs) was utilized as a cheap biosorbent and then tested for its ability to treat the reactive red (RR) dye...  相似文献   
110.
Usage of plastics has been ever increasing and now poses a tremendous threat to the environment. Millions of tons of plastics are produced annually worldwide, and the waste products have become a common feature at overflowing bins and landfills. The process of converting waste plastic into value-added fuels finds a feasible solution for recycling of plastics. Thus, two universal problems such as problems of waste plastic management and problems of fuel shortage are being tackled simultaneously. Converting waste plastics into fuel holds great promise for both the environmental and economic scenarios. In order to carry out the study on plastic wastes, the pyrolysis process was used. Pyrolysis runs without oxygen and in high temperature of about 250–300 °C. The fuel obtained from plastics is blended with B20 algae oil, which is a biodiesel obtained from microalgae. For conducting the various experiments, a 10-HP single-cylinder four-stroke direct-injection water-cooled diesel engine is employed. The engine is made to run at 1500 rpm and the load is varied gradually from 0 to 100 %. The performance, emission and combustion characteristics are observed. The BTE was observed to be higher with respect to diesel for plastic-biodiesel blend and biodiesel blend by 15.7 and 12.9 %, respectively, at full load. For plastic-biodiesel blend, the emission of UBHC and CO decreases with a slight increase in NO x as compared to diesel. It reveals that fuel properties are comparable with petroleum products. Also, the process of converting plastic waste to fuel has now turned the problems into an opportunity to make wealth from waste.  相似文献   
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