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551.
Oksana Mykytczuk Jennifer Harlow Sabah Bidawid Nathalie Corneau Neda Nasheri 《Food and environmental virology》2017,9(2):208-218
Infection with the hepatitis E virus (HEV) is very common worldwide. HEV causes acute viral hepatitis with approximately 20 million cases per year. While HEV genotypes 1 and 2 cause large waterborne and foodborne outbreaks with a significant mortality in developing countries, genotypes 3 and 4 are more prevalent in developed countries with transmission being mostly zoonotic. In North America and Europe, HEV has been increasingly detected in swine, and exposure to pigs and pork products is considered to be the primary source of infection. Therefore we set out to investigate the prevalence of HEV in retail pork products available in Canada, by screening meal-size portions of pork pâtés, raw pork sausages, and raw pork livers. The presence of the HEV genomes was determined by RT-PCR and viral RNA was quantified by digital droplet PCR. Overall, HEV was detected in 47% of the sampled pork pâtés and 10.5% of the sampled raw pork livers, but not in the sampled pork sausages, and sequencing confirmed that all HEV strains belonged to genotype 3. Further phylogenetic analysis revealed that except for one isolate that clusters with subtype 3d, all isolates belong to subtype 3a. Amino acid variations between the isolates were also observed in the sequenced capsid region. In conclusion, the prevalence of HEV in pâtés and raw pork livers observed in this study is in agreement with the current HEV distribution in pork products reported in other developed countries. 相似文献
552.
Susana L. H. Rebelo A. Melo R. Coimbra M. Emília Azenha Mariette M. Pereira Hugh D. Burrows Mohamed Sarakha 《Environmental Chemistry Letters》2007,5(1):29-33
The photodegradation of the herbicides atrazine and ametryn with visible light in aerated neutral aqueous solutions and 5,
10, 15, 20-tetrakis (2,6-dichloro-3-sulfophenyl) porphyrin or 5, 10, 15, 20-tetrakis (4-sulfophenyl) porphyrin as sensitizers
are reported for the first time. Our findings show that the degradation percentage reached 30% for atrazine and 63% for ametryn.
The final photoproducts were characterized as dealkylated s-triazines. Photolysis of the pesticides in the presence of a singlet oxygen quencher showed only a minor contribution of
this type of mechanism, while a bimolecular quenching reaction between the triplet state of the sensitizer and the pesticides
is excluded by flash photolysis studies. It is proposed that the mechanism may involve the formation of a superoxide radical
anion from the triplet state of the sensitizer and molecular oxygen, followed by a radical decomposition pathway.
Selected article from 1st International Meeting on Photochemistry, Photocatalysis and Environmental Applications, Agadir,
2006, organised by Prof. Dr. Ait Ichou, University Ibn Zohr, Agadir, Morocco 相似文献
553.
Highly efficient photodegradation of the pesticide metolcarb induced by Fe complexes 总被引:1,自引:1,他引:1
Here we show the efficient photoinduced degradation of the pesticide metolcarb, in less than 400 min, using iron(III) aquacomplexes and 365 nm light. The degradation is mainly due to the formation of hydroxyl radical. It was complete when molecular oxygen was present. The analytical study gives evidence for the primary formation of several byproducts formed from 1) the scission of the O–C bond, 2) the hydroxylation of the aromatic moiety and 3) the attack of the two methyl groups. Under prolonged irradiation and in aerated solutions, efficient mineralization was evidenced by the study of total organic carbon evolution as a function of irradiation time. 相似文献
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557.
Volatile organic compounds (VOCs) have been determined to be human risk factors in urban environments, as well as primary contributors to the formation of photochemical oxidants. Ambient air quality measurements of 54 VOCs including hydrocarbons, halogenated hydrocarbons and carbonyls were conducted in or near 13 urban locations in the United States during September 1996 to August 1997. Air samples were collected and analyzed in accordance with US Environmental Protection Agency-approved methods. The target compounds most commonly found were benzene, toluene, xylene and ethylbenzene. These aromatic compounds were highly correlated and proportionally related in a manner suggesting that the primary contributors were mobile sources in all the urban locations studied. Concentrations of total hydrocarbons ranged between 1.39 and 11.93 parts per billion, by volume (ppbv). Ambient air levels of halogenated hydrocarbons appeared to exhibit unique spatial variations, and no single factor seemed to explain trends for this group of compounds. The highest halogenated hydrocarbon concentrations ranged from 0.24 ppbv for methylene chloride to 1.22 ppbv for chloromethane. At participating urban locations for the year of data considered, levels of carbonyls were higher than the level of the other organic compound groups, suggesting that emissions from motor vehicles and photochemical reactions strongly influence ambient air concentrations of carbonyls. Of the most prevalent carbonyls, formaldehyde and acetaldehyde were the dominant compounds, ranging from 1.5-7.4 ppbv for formaldehyde, to 0.8-2.7 ppbv for acetaldehyde. 相似文献
558.
Remediation of heavy metal contaminated soils via integrated electrochemical processes 总被引:1,自引:0,他引:1
A.M.O. Mohamed 《Waste management (New York, N.Y.)》1996,16(8):741-747
The thrust of this study is to develop an in-situ method/technique capable of modifying the contaminated soil environment and maximizing contaminant extraction. Contaminated soils were compacted in electrokinetic cells to densities similar to natural field conditions. Conditioning fluids were used during the application of a direct current to solubilize the precipitated forms of heavy metals. Mobilization of contaminants as a function of time was quantified by analysing metal ion concentrations in the extracted effluents at both the anode and cathode and in the compacted specimens. For each conditioning fluid used, the removal efficiencies were evaluated based on both effluent and soil concentrations. 相似文献
559.
Communities in Cabo Delgado have a long tradition of using medicinal plants. In Mozambique, rural populations in general are highly dependent on natural resources. One example is the use of surrounding vegetation by people from Cabo Delgado. They use plants for food, handicrafts, construction, as a primary energy source and even for medicine purposes. In this survey, we examined the diversity of plant usage for medicinal purposes by 146 individuals, including adults and youth living in the Cabo Delgado province. This community quoted 16 species of plants, belonging to 13 families. Utilisation by different categories of people based on sex and age was compared and differences were found among some groups. In general, older people show a deeper knowledge of medicinal plants than younger people. Men and women show similar knowledge of medicinal plants. 相似文献
560.
Mohamed A. Mohamed Ali M. Eltamaly Abdulrahman I. Alolah A.Y. Hatata 《International Journal of Green Energy》2019,16(1):86-100
Hybrid renewable energy systems (HRES) turned into an appealing choice for supplying loads in remote areas. The application of smart grid principals in HRES provides a communication between the load and generation from the HRES. Using smart grid in the HRES will optimally utilize the generating resources to reschedule the loads depending on its importance. This paper presents a new proposed design and optimization simulation program for techno-economic sizing of grid-independent hybrid PV/wind/diesel/battery energy system using Cuckoo search (CS) optimization algorithm. Using of CS will help to get the global minimum cost condition and prevent the simulation to be stuck around local minimum. A new proposed simulation program (NPSP) is acquainted using CS to determine the optimum size of each component of the HRES for the lowest cost of generated energy and the lowest value of dummy energy, at highest reliability. A detailed economic methodology to obtain the price of the generated energy has been introduced. Results showed that using CS reduced the time required to obtain the optimal size with higher accuracy than other techniques used iterative techniques, Genetic Algorithm (GA), and Particle Swarm Optimization (PSO). Numerous significant outcomes can be extracted from the proposed program that could help scientists and decision makers. 相似文献