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471.
The effects of the five herbicides propanil, quinclorac, molinate/propanil, 2,4-D amine, and bensulfuron on Odonata diversity and abundance at the experimental rice plots was investigated. A total of 13 Odonata morphospecies belonging to two families have been identified. Treated plots exhibited higher species richness (up to 12 species) than the control plot (8 species). Ishnura spp. was the most abundant species in the treated plots with a mean density of 194.2 individuals per m2, (ind m?2) followed by Brachythemis contaminata (152 ind m?2) and Agriocnemis spp. (124 ind m?2). In the control plots, Agrocnemis spp. was the dominant species (153 ind m?2) followed by Ishnura spp. (143 ind m?2) and Neurothemis fluctuans (59 ind m?2). In the propanil-treated plot, the highest number of odonate species (10 species) was recorded followed by the plots treated with quinclorax and molinate/propanil (9 species). On the 2,4-D amine or bensulfuron-treated plots as well as the control plot, only eight odonate species were recorded. This study revealed that herbicide application had a positive effect on Odonata diversity. This seems reasonable as Odonata are non-target organisms for herbicides. Furthermore, the decomposed weeds resulting from herbicide application would enrich the water with necessary organic matter.  相似文献   
472.
Cigarette smoking is one of the main risk factors for premature human death which is associated with a variety of respiratory and vascular diseases, and cancer due to exposure to hundreds of toxicants. Rat mitochondria were obtained by differential ultracentrifugation and incubated with different concentrations (1%, 10%, or 100%) of standardized cigarette smoke extract (CSE). Our results showed that CSE induced a rise in mitochondrial reactive oxygen species (ROS) formation, lipid peroxidation, and mitochondrial membrane potential (MMP) collapse before mitochondrial swelling ensued in isolated pulmonary mitochondria. Disturbance in oxidative phosphorylation was also confirmed by decrease in ATP concentration in the CSE-treated mitochondria. In addition, collapse of MMP and mitochondrial swelling produced release of cytochrome c via outer membrane rupture or mitochondrial permeability transition (MPT) pore opening. Our results suggested that CSE-induced toxicity in lung tissue is the result of disruptive effect on mitochondrial respiratory chain that leads to ROS formation, lipid peroxidation, MMP decline, and cytochrome c expulsion which results in apoptosis signaling and cell loss.  相似文献   
473.
Carbonate shells have an astonishing ability in the removal of Cd2+ in a short time period with emphasis on being a low cost adsorbent. In the present study, the sorption capacity of carbonate shells was studied for Cd2+ in batch experiments. The influence of different carbonate shell sizes and physico-chemical factors were evaluated and the results were analyzed for its correlation matrices by using Predictive Analytics Software (PASW). The mineralogy state of aqueous solution regarding the saturation index was simulated using PHREEQC to identify the Cd2+ uptake mechanism. The Cd uptake rates were calculated as well as Ca2+, HCO 3 ? concentration, pH, ambient humidity and temperature were measured. Cd2+ removal of 91.52% was achieved after 5 h adsorption. The adsorption efficiencies were significantly influenced by pH as they increased with the increase of pH from acidic solution (5.50±0.02) to slightly alkaline (7.60±0.05). In addition, the mineralogy state of aqueous solution calculated from PHREEQC confirmed that the increment of Ca2+ and HCO 3 ? concentrations in solution was attributed to the dissolution of carbonate shells. Moreover, the ion exchange adsorption mechanism of Cd2+ toward Ca2+ was identified as the process involved in Cd2+ uptake.  相似文献   
474.
Radionuclide contamination in terrestrial ecosystems has reached a dangerous level. The major artificial radionuclide present in the environment is 137Cs, which is released as a result of weapon production related to atomic projects, accidental explosions of nuclear power plants and other sources, such as reactors, evaporation ponds, liquid storage tanks, and burial grounds. The release of potentially hazardous radionuclides (radiocesium) in recent years has provided the opportunity to conduct multidisciplinary studies on their fate and transport. Radiocesium’s high fission yield and ease of detection made it a prime candidate for early radio-ecological investigations. The facility setting provides a diverse background for the improved understanding of various factors that contribute toward the fate and transfer of radionuclides in the terrestrial ecosystem. In this review, we summarize the significant environmental radiocesium transfer factors to determine the damaging effects of radiocesium on terrestrial ecosystem. It has been found that 137Cs can trace the transport of other radionuclides that have a high affinity for binding to soil particles (silts and clays). Possible remedial methods are also discussed for contaminated terrestrial systems. This review will serve as a guideline for future studies of the fate and transport of 137Cs in terrestrial environments in the wake of the Fukushima Nuclear Power Plant disaster in 2011.  相似文献   
475.
Air pollution is a major issue leading to many serious illnesses. Exposure to formaldehyde may occur by breathing contaminated indoor air, tobacco smoke, or ambient urban air. Exposure to formaldehyde has been associated with lung and nasopharyngeal cancer. Therefore, there is a need for methods to degrade formaldehyde. Here, we studied the photocatalytic decomposition of gaseous formaldehyde over nanosized ZnO particles on bone char. The conditions were UV/bone char, UV/ZnO nanoparticles, and UV/ZnO-bone char in continuous flow mode. We investigated the effects of humidity, initial formaldehyde concentration, and residence time on decomposition of formaldehyde. Agglomeration of ZnO particles in the bone char pores was characterized by Brunauer, Emmett, and Teller surface area, and scanning electron micrograph. Results show that maximum decomposition efficiency of formaldehyde was 73 %. The optimal relative humidity was by 35 %. Findings also indicated that immobilization of ZnO nanoparticles on bone char has a synergetic action on photocatalytic degradation. This is explained by the strong adsorption of formaldehyde molecules on bone char, resulting in higher diffusion to the catalytic ZnO and thus a higher rate of photocatalysis.  相似文献   
476.
The demand to travel by rail is ever increasing because it benefits both passengers and freight; therefore it is of utmost importance for railway administrators to carry passengers and freight safely to their destinations. Undergoing safety procedures and developing safety systems require awareness of what is causing unsafe conditions. This can be accomplished by learning from the past. This research has been performed to analyze the data from past accidents of the Iranian Railway (RAI) by applying association rules data mining techniques in order to discover and reveal unknown relationships and patterns among the data. By the application of CRISP-DM as the data mining methodology and utilizing Clementine 12.0 as the software tool, the mentioned objectives of this paper were fulfilled. For this research some 6500 accident records were selected from the accidents database from 1996 to 2005. The ultimate relationships and patterns extracted can been utilized to develop regulations and rules. This research considers accident conditions and relationships discovered among the most common accident factors (human error, wagon and track) with other fields of the database in order to prevent them from occurring in the future.  相似文献   
477.
Environmental Science and Pollution Research - Fewer fossil fuel deposits, price volatility, and environmental concerns have intensified biofuel-based studies. Saccharification, gasification, and...  相似文献   
478.
Environmental Science and Pollution Research - Various treatments of choice are available to overcome contamination of bisphenol A (BPA) in the environment including membrane technologies; however,...  相似文献   
479.
Journal of Material Cycles and Waste Management - Methane has tremendous potential for energy production, and enormous amounts of energy can be produced using suitable technology. To address this...  相似文献   
480.
The global demand for wood is set to increase significantly over the next two decades. The growth is to be particularly pronounced in the Asia Pacific, and timber plantations are expected to be a major source of wood fiber. Indonesia is taking steps to meet the global demand for wood by expanding its pulp production and timber plantations. However, there are concerns about the environmental trade-offs of this expansion. The pulp sector continues to rely on natural forests for timber. The size and productivity of timber plantations are uncertain because of unreliable data. The employment and poverty alleviation potential of the pulp sector are overstated. The pulp sector continues to attract large-scale foreign capital due to high returns on undervalued timber from natural forest. However, environmentally and socially, it is a high-risk investment. The pulp sector in Indonesia can be environmentally sustainable and economically profitable, but the conversion of natural forest must be stopped; the use of non-forest land for plantations must be maximized; and smallholder tree-growing schemes must be made simpler and more attractive. Careful revision of the pulp growth targets and greater investor due diligence are needed to ensure a more sustainable future.  相似文献   
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