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981.
Abinesh Bose Najam Akhtar Shakil Pankaj Jitendra Kumar Manish K. Singh 《Journal of environmental science and health. Part. B》2013,48(3):254-261
A series of novel N-alkyl substituted amides, synthesized by enzyme catalysis, were evaluated against root-knot nematode, Meloidogyne incognita and found to have potential antinemic activity. The corresponding amides were prepared by the condensation of equimolar amounts of carboxylic acids with different alkyl amines in the presence of Candida antarctica lipase at 60–90°C in 16–20 h. The reactions were carried out in a non - solvent system without the use of any activating agents. All the products were obtained in appreciable amounts and the yields for different compounds varied between 77.4–82.3%. The synthesized compounds were characterized using spectroscopy techniques namely Infra Red (IR) and Nuclear Magnetic Resonance (NMR) (1H and 13C). Nematicidal activity of synthesized amides was evaluated against J2s of Meloidogyne incognita at 500, 250, 125 and 62.5 ppm concentrations after 24 h, 48 h and 72 h of exposure. Among all the tested compounds, N-propyl-butyramide, N-propyl-pentanamide and N-propyl-hexanamide were found to possess significant activity with LC50 values of 67.46, 83.49 and 96.53 respectively. N-propyl-butyramide with LC50 value of 67.46 ppm was found to be most active amide against J2s of Meloidogyne incognita. The bioactivity study showed that an increase in alkyl chain significantly decreased the activity of amides against root-knot nematode. 相似文献
982.
Evaluation of the individuality of white rot macro fungus for the decolorization of synthetic dye 总被引:1,自引:0,他引:1
Priyanka Pandey Ram Praksh Singh Kailash Nath Singh Paramasivam Manisankar 《Environmental science and pollution research international》2013,20(1):238-249
Introduction
A biosorbent was developed by simple dried Agaricus bisporus (SDAB) and effectively used for the biosorption of cationic dyes, Crystal Violet and Brilliant Green.Materials and methods
For the evaluation of the biosorbent system, all the batch equilibrium parameters like pH, biomass dose, contact time, and temperature were optimized to determine the decolorization efficiency of the biosorbent. The maximum yields of dye removal were achieved at pH 4.0 for Crystal Violet (CV) and pH 5.0 for Brilliant Green (BG), which are closer to their natural pH also.Result and discussion
Equilibrium was established at 60 and 40 min for CV and BG, respectively. Pseudo first-order, pseudo second-order, and intraparticle-diffusion kinetic models were studied at different temperatures. Isotherm models such as Freundlich, Langmuir, and Dubinin–Radushkevich were also studied. Biosorption processes were successfully described by Langmuir isotherm model and the pseudo second-order kinetic model.Conclusions
The biosorption capacity of A. bisporus over CV and BG were found as 21.74 and 12.16 mg gm?1. Thermodynamic parameters indicated that the CV and BG dye adsorption onto A. bisporus is spontaneous and exothermic in the single and ternary systems. Scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy were used for the surface morphology, crystalline structure of biosorbent, and dye–biosorbent interaction, respectively. This analysis of the biosorption data confirmed that these biosorption processes are ecofriendly and economical. Thus, this biomass system may be useful for the removal of contaminating cationic dyes. 相似文献983.
Vermiremediation of dyeing sludge from textile mill with the help of exotic earthworm Eisenia fetida Savigny 总被引:1,自引:0,他引:1
Sartaj Ahmad Bhat Jaswinder Singh Adarsh Pal Vig 《Environmental science and pollution research international》2013,20(9):5975-5982
The aim of present study was for the vermiremediation of dyeing sludge from textile mill into nutrient-rich vermicompost using earthworm Eisenia fetida. The dyeing sludge was mixed with cattle dung in different ratios, i.e., 0:100 (D0), 25:75 (D25), 50:50 (D50), 75:25 (D75), and 100:0 (D100) with earthworms, and 0:100 (S0), 25:75 (S25), 50:50 (S50), 75:25 (S75), and 100:0 (S100) without earthworms. Minimum mortality and maximum population build-up were observed in a 25:75 mixture. Nitrogen, phosphorus, sodium, and pH increased from the initial to the final products with earthworms, while electrical conductivity, C/N ratio, organic carbon, and potassium declined in all the feed mixtures. Vermicomposting with E. fetida was better for composting to change this sludge into nutrient-rich manure. 相似文献
984.
Anil Kumar Singh Swaranjit Singh Cameotra 《Environmental science and pollution research international》2013,20(10):7367-7376
This study describes the potential application of lipopeptide biosurfactants in removal of petroleum hydrocarbons and heavy metals from the soil samples collected from industrial dumping site. High concentrations of heavy metals (like iron, lead, nickel, cadmium, copper, cobalt and zinc) and petroleum hydrocarbons were present in the contaminated soil samples. Lipopeptide biosurfactant, consisting of surfactin and fengycin was obtained from Bacillus subtilis A21. Soil washing with biosurfactant solution removed significant amount of petroleum hydrocarbon (64.5 %) and metals namely cadmium (44.2 %), cobalt (35.4 %), lead (40.3 %), nickel (32.2 %), copper (26.2 %) and zinc (32.07 %). Parameters like surfactant concentration, temperature, agitation condition and pH of the washing solution influenced the pollutant removing ability of biosurfactant mixture. Biosurfactant exhibited substantial hydrocarbon solubility above its critical micelle concentration. During washing, 50 % of biosurfactant was sorbed to the soil particles decreasing effective concentration during washing process. Biosurfactant washed soil exhibited 100 % mustard seed germination contradictory to water washed soil where no germination was observed. The results indicate that the soil washing with mixture of lipopeptide biosurfactants at concentrations above its critical micelle concentration can be an efficient and environment friendly approach for removing pollutants (petroleum hydrocarbon and heavy metals) from contaminated soil. 相似文献
985.
Loha KM Shakil NA Kumar J Singh MK Srivastava C 《Journal of environmental science and health. Part. B》2012,47(7):687-691
In the present investigation, bioefficacy of developed β-cyfluthrin formulations, utilizing laboratory synthesized poly(ethylene glycols) based amphiphilic copolymers, were evaluated against Callosobruchus maculatus (Coleoptera: Bruchidae). The bioefficacy data indicated that the formulations developed by utilizing polymers having PEG - 1500 (3c) and PEG - 2000 (3d) as the hydrophilic segment showed greater efficacy after 14 days as evident from EC(50) values (2.2 and 1.58 mg L(-1) respectively). Also, release from the commercial SC formulation was faster than developed formulations as the commercial formulation had the lowest EC(50) value on the first day (0.51 mg L(-1)). The mean EC(50) of the commercial formulation against C. maculatus was quite high as compared to those of developed formulations. The results suggest that depending upon the polymer matrix used, the application rate of β-cyfluthrin can be optimized to achieve insect control at the desired level and period. The results described in this paper are promising and provide a comparison of developed formulations with the commercial one showing an earlier degradation of β-cyfluthrin in the latter and relatively prolonged activity in the former. 相似文献
986.
Adsorption of metolachlor and atrazine was studied in the fly ash (Inderprastha and Badarpur)- amended Inceptisol and Alfisol soils using batch method. Results indicated that sorption of both the herbicides in soil+fly ash mixtures was highly nonlinear and sorption decreased with a higher herbicide concentration in the solution. Also, nonlinearity increased with an increase in the level of fly ash amendment from 0-5%. Three two-parameter monolayer isotherms viz. Langmuir, Temkin, Jovanovic and one imperical Freundlich models were used to fit the experimental data. Data analysis and comparison revealed that the Temkin and the Freundlich isotherms were best-suited to explain the sorption results and the observed and the calculated adsorption coefficient values showed less variability. The study suggested that sorption mechanism of metolachlor and atrazine involved the physical association at the sorbate surface and the nonlinearity in the sorption at higher pesticide or fly ash concentration was due to a decrease in the heat of adsorption and higher binding energy. 相似文献
987.
Antecedents of organizational and community embeddedness: The roles of support,psychological safety,and need to belong
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Defining embeddedness as a psychological construct that influences individuals to stay, we draw on conservation of resources theory to develop and test a model of the influence of contextual social support resources on both organizational and community forms of embeddedness. In addition to the direct relationship between support and embeddedness, we also assess the mediating influence of organizational and community psychological safety and the moderating impact of need to belong. Using a multisource sample of employees and coworkers (N = 165), we found support for most of the hypotheses. Social support resources emanating from the organization and the community were positively associated with embeddedness in each domain, and psychological safety mediated these relationships. We also found that need to belong was an important boundary condition in the determination of organizational embeddedness. We discuss the theoretical contributions and practical implications of our findings. 相似文献
988.
Receptor modeling for source apportionment of polycyclic aromatic hydrocarbons in urban atmosphere 总被引:1,自引:0,他引:1
Singh KP Malik A Kumar R Saxena P Sinha S 《Environmental monitoring and assessment》2008,136(1-3):183-196
This study reports source apportionment of polycyclic aromatic hydrocarbons (PAHs) in particulate depositions on vegetation
foliages near highway in the urban environment of Lucknow city (India) using the principal components analysis/absolute principal
components scores (PCA/APCS) receptor modeling approach. The multivariate method enables identification of major PAHs sources
along with their quantitative contributions with respect to individual PAH. The PCA identified three major sources of PAHs
viz. combustion, vehicular emissions, and diesel based activities. The PCA/APCS receptor modeling approach revealed that the
combustion sources (natural gas, wood, coal/coke, biomass) contributed 19–97% of various PAHs, vehicular emissions 0–70%,
diesel based sources 0–81% and other miscellaneous sources 0–20% of different PAHs. The contributions of major pyrolytic and
petrogenic sources to the total PAHs were 56 and 42%, respectively. Further, the combustion related sources contribute major
fraction of the carcinogenic PAHs in the study area. High correlation coefficient (R
2 > 0.75 for most PAHs) between the measured and predicted concentrations of PAHs suggests for the applicability of the PCA/APCS
receptor modeling approach for estimation of source contribution to the PAHs in particulates. 相似文献
989.
Visibility impairing aerosols in the urban atmosphere of Delhi 总被引:1,自引:0,他引:1
Singh T Khillare PS Shridhar V Agarwal T 《Environmental monitoring and assessment》2008,141(1-3):67-77
To study the visual air quality of Delhi, size fractionated aerosols – coarse and fine fractions of PM10 – were collected and analysed for and EC at three sites with different background activities. The analysed species constitute a smaller portion of coarse fraction
(39%) but a larger portion of fine fraction (69%). The sampling was performed from June 2003 to November 2003 which covers
monsoon and post monsoon seasons.Aerosol data was used to describe the spatial variation of Visibility Range as a function
of chemical composition of visibility impairing aerosols. During the study period, visibility was found to be poor varying
between 4.7 and 13 km with an average value of 9.4 km. It is observed that visibility impairment was more due to carbonaceous
aerosol followed by sulphate. 相似文献
990.
Barman SC Singh R Negi MP Bhargava SK 《Environmental monitoring and assessment》2008,137(1-3):495-504
The present study deals with the effect of fireworks on ambient air quality during Diwali Festival in Lucknow City. In this
study, PM10, SO2, NO
x
and 10 trace metals associated with PM10 were estimated at four representative locations, during day and night times for Pre Diwali (day before Diwali) and Diwali
day. On Diwali day 24 h average concentration of PM10, SO2, and NO
x
was found to be 753.3, 139.1, and 107.3 μg m−3, respectively, and these concentrations were found to be higher at 2.49 and 5.67 times for PM10, 1.95 and 6.59 times for SO2 and 1.79 and 2.69 for NO
x
, when compared with the respective concentration of Pre Diwali and normal day, respectively. On Diwali day, 24 h values for
PM10, SO2, and NO
x
were found to be higher than prescribed limit of National Ambient Air Quality Standard (NAAQS), and exceptionally high (7.53
times) for PM10. On Diwali night (12 h) mean level of PM10, SO2 and NO
x
was 1,206.2, 205.4 and 149.0 μg m−3, respectively, which was 4.02, 2.82 and 2.27 times higher than their respective daytime concentrations and showed strong
correlations (p < 0.01) with each other. The 24 h mean concentration of metals associated with PM10 was found to be in the order of Ca (3,169.44) > Fe (747.23) > Zn (542.62) > Cu (454.03), > Pb (307.54) > Mn (83.90) > Co
(78.69) > Cr (42.10) > Ni (41.47) > Cd (34.69) in ng m−3 and all these values were found to be higher than the Pre Diwali (except Fe) and normal day. The metal concentrations on
Diwali day were found to be significantly different than normal day (except Fe & Cu). The concentrations of Co, Ni, Cr and
Cd on Diwali night were found to be significantly higher than daytime concentrations for Pre Diwali (control). The inter correlation
of metals between Ca with Pb, Zn with Ni and Cr, Cu with Co, Co with Mn, Ni with Cd, Mn with Cd, Ni with Cd and Cr, and Cr
with Cd showed significant relation either at p < 0.05 or P < 0.01 levels, which indicated that their sources were the same. The metals Cu, Co, Ni, Cr and Cd showed significant (p < 0.01) association with PM10. These results indicate that fireworks during Diwali festival affected the ambient air quality adversely due to emission
and accumulation of PM10, SO2, NO
x
and trace metals.
ITRC Communication Number 2538 相似文献