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931.
Abstract

The effects of wastewater from olive processing on seed germination and early plant growth of different vegetable species were examined. Three types of wastewater at different concentrations were tested: raw wastewater, wastewater with organic matter removed and deionized wastewater.

Results generally indicate an inhibitory effect on seed germination and early plant growth by all treatments containing any kind of wastewater. Of the three types of effluent, raw wastewater had the greatest depressive effect, followed by deionized wastewater and finally effluent with organic matter removed. Barley showed the least sensitivity to phytotoxic effects while tomato was the plant most affected. The remaining vegetable species showed an intermediate sensitivity.  相似文献   
932.
Abstract

The susceptibility of wild mallard ducklings to the delayed neurotoxic effect of the neurotoxic organophosphorus insecticides cyanofenphos and leptophos was evaluated following a daily dosing regimen. Ducklings were treated daily with either cyanofenphos or with leptophos at different dose levels for 90 days, or until they died, or became paralyzed. A control group of ducklings given corn oil at 1 ml/kg daily for 90 days was used for comparison. All treated birds were observed daily for any clinical signs of neurotoxicity during the course of this study. All of the surviving ducklings that were treated with cyanofenphos at 4 mg/kg/day or leptophos at 10 mg/kg/day developed clinical signs of delayed neurotoxicity after 7 to 11 weeks of intoxication. Symptoms included leg weakness, ataxia, severe ataxia and paralysis. The observed clinical signs were confirmed by histological changes found in the spinal cords of the treated birds. These changes were of the type associated with organophosphorus‐induced delayed neuropathy (OPIDN). These results demonstrate that wild mallard ducklings are susceptible to OPIDN and this avian species can be used in screening organophos‐phorus compounds for such effect.  相似文献   
933.
Abstract

Human serum transferrin (HSTF), human serum albumin (HSA) and rat serum were compared for their interaction with AlCl3 , in a Tris‐HCl buffer solutions (pH 7.4). The AlCl3 was tested in series of concentrations in the range of 50 μM up to 500 μM . HSTF, HSA and their 1:1 mixture and rat serum were incubated at 37°C with series of AlCl3 concentrations. The protein profile of the incubated solutions were compared to control using SDS‐PAGE and FPLC tests. The results indicated that HSTF was more specifically responsive to AlCl3showing a characteristic increase in its UV absorption, peak and area dimensions. Simultaneously, HSA was less affected, but it showed a significant shift with an increase in molecular weight accompanied with a change in its profile. The respective bands of transferrin and albumin in rat serum behaved similarly. The SDS‐PAGE and FPLC data coincided and confirmed the preferential affinity of HSTF to bind with Al3+ . These results support the suggestion of using HSTF for monitoring levels of Al3+ in human blood samples of exposed population. The importance of further developing such a biomarker is the increased demand for early detection of the hazardous levels of Al3+ in relation to its long term neurotoxic adverse effects.  相似文献   
934.
Abstract

The mobility of seven pesticides in a chromic cambisol soil was studied by soil thin layer chromatography. Pesticide mobilities were determined by means of conventional autoradiographs of the chromatograms, as well as from sequential series of curves and images of the pesticide spots provided by a linear analyser. The R f values obtained from the autoradiographs and those provided by the linear analyser were quite consistent. Based on such values, pesticide mobility decreased in the following order: acephate > fluometuron > atrazine > ethofumesate > metolachlor > diazinon > glyphosate. According to the mobility scale proposed by Helling and Turner (1968), acephate is highly mobile; atrazine, fluometuron, ethofumesate and metolachlor are moderately mobile; diazinon is slightly mobile; and glyphosate is immobile. The images provided by the linear analyser allow to determine the R f values for the zones of maximum activity in the pesticide spots (R f max), as well as the activities of different spot zones and those corresponding to R f and R f max. The results obtained show the image analyser to provide more expeditious R f measurements from the chromatograms and open up new prospects for using soil TLC to investigate pesticide mobility.  相似文献   
935.
Abstract

A bacteria additives treatment experiment in assessing the changes in gaseous mass transfer from stored swine manure is presented. The experiment is tested for ammonia, methane, hydrogen sulfide, and carbon dioxide emission data sampled from pilot swine manure columns and analyzed by GC/MS. The result shows that bacteria additives slightly reduce the methane and carbon dioxide releases, while the same additives do not show any effect on the reduction of ammonia. The hydrogen sulfide contents of stored swine manure continued to be low. Gas concentrations emitted from treated and untreated stored swine manure were: 3.76 and 2.2 ppm for methane, 0.35 and 0.11 ppm for ammonia, and 1000 and 470 ppm for carbon dioxide, respectively. A simple model to estimate gas emission rates is also developed from the viewpoint of two‐film resistance theory. The average emission rates calculated from the model for methane, ammonia, and carbon dioxide are respectively: 0.01, 0.0005, and 13.98 g/min from untreated stored manure; while 0.07, 0.096, and 0.55 g/min from treated manure. The emission model also indicates that for most gaseous pollutants of environmental concern, liquid phase transfer coefficient controls the rate of volatile compounds emitted from stored swine manure and gas phase transfer coefficient has insignificant effect in the calculation of overall mass transfer coefficient.  相似文献   
936.
Abstract

A study was conducted from summer 1995 to summer 1997 to assess the seasonal occurrence of pesticide residues and other organic contaminants, polychlorinated biphenyls (PCBs), in water at the estuaries of Rosetta and Damiatta branches of the Nile river. The results indicated that organochlorine compounds (OCs) including HCB, lindane, p,p‘‐DDE, p,p‘DDD, p,p‘‐DDT, aroclor 1254 and aroclor 1260 were present in all the water samples at concentration levels ranging between 0.195–0.240, 0.286–0.352, 0.035–0.067, 0.019–0.033, 0.024–0.031, 0.390–0.70 and 0.166–0.330 μg/l, respectively. The levels of these compounds were higher in water of Damiatta branch than those found in water of Rosetta branch. Aldrin, dieldrin and endrin were not detected in all water samples. Only 4 compounds from 36 organophosphorus insecticides, fungicides and s‐triazine herbicides tested were detected in water samples collected during summer and autumn seasons from Rosetta branch. The concentration levels of these detected compounds, dimethoate, malathion, captan, and ametryne, ranged from 0.011 to 0.340 μg/l, respectively. Similar compounds during the same seasons as found in water of Rosetta branch were also detected in water of Damiatta branch except ametryne. The levels of the detected compounds (dimethoate, malathion and captan) ranged between 0.030 and 0.330 μg/l. The levels of detected organophosphorus insecticides, fungicides and s‐triazine herbicides were in the order: dimethoate > malathion > captan > ametryne.  相似文献   
937.
    
We introduce a rich class of models π( Y | C , θ ) for multivariate constrained, zero‐inflated counts data. We use new methodology for fast Bayesian inference on unobserved θ given matched training data and propose a new algorithm for fast inversion to π( C | Y ). Such models arise in palaeoclimate reconstruction, where Y represents vector of counts of a proxy such as pollen and C represents climate. Subsequently, is a vector of counts in a sample reflecting ancient pollen rain and thus ancient climate (the palaeoclimate). The methodology applies in principle to palaeoclimate reconstruction from other proxy types (e.g. chironomids, diatoms, testate amoebae). Furthermore, the generic issue—the statistical inversion of a multivariate relationship—is found in many areas of application (e.g. clustering, supervised classification, medical imaging, oil shale modelling). The contribution of the paper is the application of a Nested‐Dirichlet–Multinomial model in conjunction with models for zero inflation and non‐parametric response surface modelling. We present the models and the tools to perform fast Bayesian inference on the forward problem and inversion, by using integrated nested Laplace approximations. We demonstrate the increase in precision associated with including more climate proxies and the increase in error associated with doing this naïvely. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
938.
    
Electronics manufacturing industries have rapidly developed in South Korea. To reduce the use of fluorinated gases having high global warming potential (GWP) in their processes, companies have recently attempted to replace these gases with nitrous oxide (N2O). Unfortunately, N2O itself has a GWP of 310 and is one of the main greenhouse gases. The electronics manufacturing industries should therefore consider reducing N2O emissions from their processes. This study measured the N2O emission from a large display manufacturing plant in South Korea and investigated the removal of N2O at the site of the plant by either a catalytic decomposition process or a reduction process. We suggest a hybrid N2O reduction process to effectively reduce the N2O emissions of the electronics manufacturing industries. © 2012 Society of Chemical Industry and John Wiley & Sons, Ltd  相似文献   
939.
    
Uncontrolled massive release of the primary greenhouse gas carbon dioxide (CO2) into atmosphere from anthropogenic activities poses a big threat and adversely affects our global climate and natural environment. One promising approach to mitigate CO2 emission is carbon capture and storage (CCS), in which ideal adsorbent materials with high storage capacity and excellent adsorption selectivity over other gases are urgently needed. For practical applications in CO2 capture from flue gas of power plants, the biggest single contributor of anthropogenic CO2 emission, the adsorbent materials must also be chemically stable, be easy to regenerate with minimal energy input, and be easily synthesized with low capital cost. Metal‐organic frameworks (MOFs), highly crystalline porous materials constructed by metal ions and organic ligands, have emerged as a class of excellent adsorbent materials for carbon capture. Great progress in MOF materials for CO2 capture has been made in the past and reviewed accordingly, but new discoveries are constantly being made as the field quickly grows. In this paper, we provide a short review on the most recent advances in using MOFs for CO2 adsorption, storage, and separation that are directly related to CO2 capture. Some of the important properties of MOF adsorbents which are crucial for practical applications but are largely overlooked in research carried out so far are discussed. © 2012 Society of Chemical Industry and John Wiley & Sons, Ltd  相似文献   
940.
    
In many applications, observed spatial variables have skewed distributions. It is often of interest to model the shape of the skewed marginal distributions as well as the spatial correlations. We propose a class of stationary processes that have skewed marginal distributions. The covariance function of the process can be given explicitly. We study maximum likelihood inference through a Monte Carlo EM algorithm, and develop a method for the minimum mean‐square error prediction. We also present two applications of the process. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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