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41.
This article proposed and tested a multilevel and interactional model of individual innovation in which weekly moods represent a core construct between context, personality, and innovative work behavior. Adopting the circumplex model of affect, innovative work behavior is proposed as resulting from weekly positive and high‐activated mood. Furthermore, drawing on the Big Five model of personality and cognitive appraisal theory, openness to experience and support for innovation are proposed as individual and contextual variables, respectively, which interplay in this process. Openness to experience interacts with support for innovation leading to high‐activated positive mood. Furthermore, openness interacts with these feelings leading to greater levels of innovative work behavior. Overall, the model entails a moderated mediation process where weekly high‐activated positive mood represents a crucial variable for transforming contextual and individual resources into innovative outcomes. These propositions were tested and supported using a diary methodology and multilevel structural equation modeling, on the basis of 893 observations of innovative work behavior and moods nested in 10 weekly waves of data. This information was collected from 92 individuals of diverse occupations employed in 73 distinct companies. Theoretical and practical implications are discussed. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
42.
Phytoaccumulation of heavy metals by aquatic plants   总被引:14,自引:0,他引:14  
Three aquatic plants were examined for their ability to remove heavy metals from contaminated water: parrot feather (Myriophylhum aquaticum), creeping primrose (Ludwigina palustris), and water mint (Mentha aquatic). The plants were obtained from a Solar Aquatic System treating municipal wastewater. All the three plants were able to remove Fe, Zn, Cu, and Hg from the contaminated water. The average removal efficiency for the three plant species was 99.8%, 76.7%, 41.62%, and 33.9% of Hg, Fe, Cu, and Zn, respectively. The removal rates of zinc and copper were constant (0.48 mg/l/day for Zn and 0.11 mg/l/day for Cu), whereas those of iron and mercury were dependent on the concentration of these elements in the contaminated water and ranged from 7.00 to 0.41 mg/l/day for Fe and 0.0787 to 0.0002 mg/l/day for Hg. Parrot feather showed greater tolerance to toxicity followed by water mint and creeping primrose. The growth of creeping primrose was significantly affected by heavy metal toxicity. The selectivity of heavy metals for the three plant species was the same (Hg>Fe>Cu>Zn). The mass balance preformed on the system showed that about 60.45-82.61% of the zinc and 38.96-60.75% of the copper were removed by precipitation as zinc phosphate and copper phosphate, respectively.  相似文献   
43.
The ‘Blue Economy’ is an increasingly popular term in modern marine and ocean governance. The concept seeks to marry ocean-based development opportunities with environmental stewardship and protection. Yet different actors are co-opting this term in competing, and often conflicting ways. Four conceptual interpretations of the Blue Economy are identified, through examination of dominant discourses within international Blue Economy policy documents and key ‘grey’ literature. The way the Blue Economy is enacted is also examined, through an analysis of the Blue Economy ‘in practice’, and the actors involved. Finally, the scope of the Blue Economy is explored, with a particular focus on which particular marine industries are included or excluded from different conceptualizations. This analysis reveals areas of both consensus and conflict. Areas of consensus reflect the growing trend towards commodification and valuation of nature, the designation and delimitation of spatial boundaries in the oceans and increasing securitization of the world's oceans. Areas of conflict exist most notably around a divergence in opinions over the legitimacy of individual sectors as components of the ‘Blue Economy’, in particular, carbon-intensive industries like oil and gas, and the emerging industry of deep seabed mining.  相似文献   
44.
Cities in Bangladesh produce large amounts of solid waste (SW) through various human activities which severely pollutes our native environment. As a result, SW pollutes the three basic environmental elements (air, water, and soil) by increasing pathogenic microbial load, which might be hazardous to public health directly or indirectly. In this study, we conducted 30 samples (i.e., soil, water, and air) collected from areas where municipal solid wastes are dumped (Tangail Sadar Upazila, Bangladesh). All the samples were analyzed to assess bacteriological quality for presumptive viable and coliform count using different agar media. We performed serial dilution 10−3–10−10 times for soil and water samples, and the diluted samples were spread on Mac-Conkey agar and nutrient agar plates. For the air sample, the sterile media containing petri-dish was placed adjacent to the dumpsite of the municipal waste and kept for an hour. Then all the samples were incubated at 37°C overnight for total viable count (TVC) and total coliform count (TCC). Biochemical tests and PCR were performed for the identification of these microorganisms. The antibiogram study was performed to reveal their (identified bacteria) susceptibility against clinically used antibiotics according to the standard disk diffusion technique. The highest bacterial loads were found in the air: TVC 3.273 × 103 and TCC 1.059 × 103 CFU/plate; tube-well water: TVC 8.609 × 103, and TCC 8.317 × 103 CFU/mL; in surface water: TVC 6.24 × 1013 CFU/mL and TCC 2.2 × 1012 CFU/mL; in soil: TVC 2.88 × 1011 and TCC 1.02 × 1011 CFU/g, respectively. Microbes from SW can be transmitted through air, dust particles, or flies, and here we found an average of 1120 microbes spread over 63.61 cm2 area per hour. Eight bacterial isolates (Pseudomonas spp., Klebsiella spp., E. coli, Proteus spp., V. cholera, Salmonella spp., Shigella spp., and Vibrio spp.) were identified by the biochemical test. Among them, E. coli and Shigella spp. were further ensured by PCR targeting bfpA and ipaH genes. Antibiotic susceptibility test results showed that E. coli isolates were highly resistant to erythromycin (80%); Shigella spp. were resistant to nalidixic acid (90%), whereas Salmonella spp. was found resistant to kanamycin (90%). Vibrio spp. were also resistant to azithromycin (80%) and erythromycin (80%), which should be a great concern for us. A semi-structured survey revealed that 63% of respondents suffered from different clinical conditions (intestinal diseases) due to SW pollution. So, steps should be taken to improve the proper management and disposal of solid waste and liquid effluent to save our environment and public health.  相似文献   
45.
This paper reports a numerical study on dam-break waves over movable beds. A one-dimensional (1-D) model is built upon the Saint-Venant equations for shallow water waves, the Exner equation of sediment mass conservation and a spatial lag equation for non-equilibrium sediment transport. The set of governing equations is solved using an explicit finite difference scheme. The model is tested in various idealized experimental cases, with fairly good agreement between the numerical predictions and measurements. Discrepancies are observed at the earlier stage of the dam-break wave and around the dam location due to no vertical velocity component being taken into account. Sensitivity tests confirm that the friction coefficient is an important parameter for the evaluation of sediment transport processes operating during a dam-break wave. The influence of the non-equilibrium adaptation length (or the lag distance) is negligible on the wavefront celerity and weak on the free surface and bed profiles, which indicates that one may ignore the spatial lag effect in dam-break wave studies. Finally, the simulation of the Lake Ha!Ha! dyke-break flood event shows that the model can provide relevant results if a convenient formula for computing the sediment transport capacity and an appropriate median grain diameter of riverbed material are selected.  相似文献   
46.
Environmental Science and Pollution Research - Although increased attempts to preserve biodiversity ecosystems have been widely publicized, bibliometric research of biodiversity loss remains...  相似文献   
47.
Journal of Material Cycles and Waste Management - Growing concern over fossil fuel depletion and the environmental impact of greenhouse gases have driven the demand for solid biofuel energy as an...  相似文献   
48.
An improved chemical oxidation pretreatment method has been developed for the determination of elemental carbon (EC) [also known as black carbon (BC) or soot] in lake sediments, using a thermal–optical transmittance (TOT) carbon analyzer. The method employs six steps: (1) removal of carbonates by treatment with HCl; (2) removal of silicates by treatment with HF + HCl; (3) removal of any remaining carbonates by treatment with HCl; (4) removal of humic acids by treatment with NaOH; and (5) oxidation of kerogens by K2Cr2O7 + H2SO4. A critical step of zinc chloride treatment was added; this apparently changes EC's morphology and enhances retention on quartz fiber filter, resulting in several-fold increased chemical yield. EC was determined using the TOT method with modified combustion timings. Carbon black (acetylene) and four NIST standard reference materials (SRMs) were used for quality control, and to assess the precision of the analysis. The EC recoveries from 18 carbon black samples varied from 90 to 111%, with a mean value of 99 ± 6%. The high EC recoveries confirmed the validity of the method. Char reference materials (i.e. chestnut wood and grass char) were used to determine potential contribution to EC in our measurements. The char references containing about 700 mg total organic carbon (OC) contributed ~1.5% EC. The measured EC values from four NIST standards were 17.0 ± 0.6, 24.2 ± 3.2, 5.6, and 1.9 ± 0.1 mg gdw?1 for SRM-1648, SRM-1649a, SRM-1941b and SRM-8704, respectively. These values in SRMs were in agreement (<±4%) with the previously reported values. The method was applied to determine the EC in sediment cores from an urban lake and a remote mountain lake in the Northeastern United States. The EC concentrations in two lakes mimic the model EC emissions from the industrial revolution in United States.  相似文献   
49.
Abstract

The mutagenic activity of chlordimeform and two of its breakdown products, 4‐chloro‐o‐toludine and 4‐chloro‐N‐formyl‐o‐toluidine were determined with five histidine dependent strains of Salmonella typhimurium (TA1535, TA1537, TA1538, TA98, TA100) and five tryptophan dependent strains of E. coli WP2. (WP2, WP2uvrA, WP67, CM611, CM571) with and without rat liver microsomal enzymes. 4‐chloro‐o‐toluidine increased the number of the reversions of the S. typhimurium strain TA1535 more than two fold over spontaneous at the concentration of 400 μg/plate.

The results of the DNA repair tests in the Salmonella TA1538/TA1978 and E. coli multirepair deficient systems showed that both breakdown products were active in inducing damage not repaired in at least one repair deficient strain while chlordimeform itself was inactive.  相似文献   
50.
Many freshwater bodies worldwide that suffer from harmful algal blooms would benefit for their management from a simple ecological model that requires few field data, e.g. for early warning systems. Beyond a certain degree, adding processes to ecological models can reduce model predictive capabilities. In this work, we assess whether a simple ecological model without nutrients is able to describe the succession of cyanobacterial blooms of different species in a hypereutrophic reservoir and help understand the factors that determine these blooms. In our study site, Karaoun Reservoir, Lebanon, cyanobacteria Aphanizomenon ovalisporum and Microcystis aeruginosa alternatively bloom. A simple configuration of the model DYRESM-CAEDYM was used; both cyanobacteria were simulated, with constant vertical migration velocity for A. ovalisporum, with vertical migration velocity dependent on light for M. aeruginosa and with growth limited by light and temperature and not by nutrients for both species. The model was calibrated on two successive years with contrasted bloom patterns and high variations in water level. It was able to reproduce the measurements; it showed a good performance for the water level (root-mean-square error (RMSE) lower than 1 m, annual variation of 25 m), water temperature profiles (RMSE of 0.22–1.41 °C, range 13–28 °C) and cyanobacteria biomass (RMSE of 1–57 μg Chl a L?1, range 0–206 μg Chl a L?1). The model also helped understand the succession of blooms in both years. The model results suggest that the higher growth rate of M. aeruginosa during favourable temperature and light conditions allowed it to outgrow A. ovalisporum. Our results show that simple model configurations can be sufficient not only for theoretical works when few major processes can be identified but also for operational applications. This approach could be transposed on other hypereutrophic lakes and reservoirs to describe the competition between dominant phytoplankton species, contribute to early warning systems or be used for management scenarios.  相似文献   
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