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681.
Objectives: Considering the high mortality rate of pedestrians in traffic accidents in Iran, the present study aimed to determine the high-risk and low-risk areas of accidents resulting in pedestrian deaths and the spatial analysis of their mortality rates.

Methods: This cross-sectional study included 4,371 deceased pedestrians reported by the Legal Medicine Organization in Iran from March 2012 to March 2013. For spatial analysis, the collected data were entered into ArcGIS software version 10.2 and a spatial map of the mortality rate was drawn according to the distribution of data in the provinces. Using this software, high-risk and low-risk areas were identified by calculating the spatial autocorrelation of the data. The Moran’s index of road accident patterns was surveyed and high-risk and low-risk points were identified using the local Getis index.

Results: The age-standardized incidence rate was 6.8 per 100,000. After analyzing the data using ArcGIS software, the local Moran’s index showed a cluster pattern with a high mortality rate in 3 provinces of Mazandaran, Gilan, and Qazvin. In identifying high-risk and low-risk points, the local Getis index showed 3 hot spots with a confidence interval of 99% in Qom, Qazvin, and Mazandaran and 5 hot spots with a 95% confidence interval in Markazi, Tehran, Zanjan, Gilan, and Golestan provinces.

Conclusions: According to the cluster pattern of accidents in the 3 provinces and the presence of hot spots in 9 provinces, it is necessary to identify factors that increase the risk of death in the study provinces in order to reduce the mortality rate among pedestrians due to traffic accidents. Therefore, to reduce the pedestrian mortality rate, especially in high-risk provinces, some studies need to be conducted to determine the risk factors in pedestrian mortality.  相似文献   

682.

This study investigated the characteristics of iron corrosion scales in pipes at tube well, overhead tank, and consumers’ end in older untreated water distribution system in Peshawar city, Pakistan. Effect of water quality conditions on corrosion scales and that of scales on drinking water quality in such systems was also assessed by undertaking a comparison with new piped distribution systems. The scales were analyzed for chemical composition and morphology using X-ray diffraction (XRD), inductively coupled plasma (ICP), and a scanning electron microscope (SEM), while water quality was examined for physicochemical and biological characteristics. The main crystalline phases of corrosion scales were goethite, magnetite, siderite, and quartz. From tube well to consumers’ end, goethite increased from 36 up to 48%, quartz declined from 22 to 15%, while magnetite fluctuated and siderite disappeared. Elemental composition of scales showed the deposition of Zn, Al, Mn, Cr, Pb, Cu, As, and Cd with Zn (13.9 g/kg) and Al (3.6 g/kg) in highest proportion. The SEM analysis illustrated the presence of microbial communities indicating the formation of biofilms in the corrosion scales. The significant difference (P <?0.05) in levels of dissolved oxygen (DO), Cl?, SiO44?, electrical conductivity (EC), SO42?, NO3?, alkalinity, hardness, and trace metals between old (DS-O) and new piped systems indicated their role in corrosion scale formation/destabilization and the effect of scale dissolution on water quality. In DS-O, EC, Cu, and Mn were significantly higher (P?<?0.05), whereas turbidity, EC, DO, and SiO44? significantly increased from source to consumers’ end implying a higher dissolution of scales and lowered corrosion rates in DS-O to utilize SiO44? and DO for iron oxidation.

  相似文献   
683.
Environmental Chemistry Letters - Global warming may be slowed down by carbon capture and storage systems that allow to sequester carbon dioxide from large fixed point sources such as power plants...  相似文献   
684.
685.
In this study, several bio-source-fuels like fresh and waste vegetable oil and waste animal fat were tested at different injector pressures (120, 140, 190, 210 bar) in a direct-injection, naturally aspirated, single-cylinder diesel engine with a design injection pressure of 190 bar. Using 2k factorial analysis, the effect of injection pressure (Pi) and fuel type on three engine parameters, namely, combustion efficiency (etac), mass fuel consumption (mf), and engine speed (N) was examined. It was found that Pi and fuel type significantly affected both etac and mf while they had a slight effect on engine speed. Moreover, with diesel and biodiesels, the etac increased to a maximum at 190 bar but declined at the higher Pi value. In contrast, higher Pi had a favorable effect on etac over the whole Pi range with all the other more viscous fuels tested. In addition, the mass fuel consumption consistently decreased with an increase in Pi for all the fuels including the baseline diesel fuel, with which the engine consistently attained higher etac and higher rpm compared to all the other fuels tested.  相似文献   
686.
The effects of unprocessed olive mill wastewaters (OMW) on soil characteristics were investigated. Phenolic compounds levels in the treated soil were compared to those of a control soil profile. Results showed that OMW infiltration caused a modification of soil physicochemical characteristics. Phenolic compounds were detected at a depth of 1.2m four months after the last application of OMW. A moderate phytotoxic residual phenolic fraction (F) was extracted from the superficial soil layer 1 year after the OMW application. This residual F had a phytotoxic potential comparable to that of 25-fold diluted OMW.  相似文献   
687.
A behavior based safety approach at a Kuwait research institution   总被引:4,自引:0,他引:4  
INTRODUCTION: Behavior based safety (BBS) initiatives are the current trend toward improving safety performance. METHOD: This study outlines the framework of the BBS process and summarizes several behavioral safety approaches to accident prevention. RESULTS: Although most of the published research has focused on the improvement of safe behavior in industry, this study is the first to apply the current approach of behavior based safety in a research/educational setting. An experiment conducted at a research institution demonstrated the effectiveness of a well-designed behavior based safety process. A follow-up study indicated that the BBS produced a lasting effect for the experimental group. IMPACT ON INDUSTRY: Results from this study can be the driving force to implement behavior-based safety processes into educational, research, and training organizations.  相似文献   
688.
The cement dust is one of the causes of pollution in the environment. In the present study, the cadmium concentrations of soil and plant specimens taken from a rural area exposed to cement factory emissions were determined and also the blood concentrations and sensitivity conditions in humans residing in this rural area were investigated. The 108 soil (36 for control) and plant specimens were collected from eight different directions of the cement plant located in Cukurhisar town in Eski?ehir city. Blood samples of the individuals residing in this area were taken from 258 subjects (258 for control) following a physical examination, and patch tests were also applied. The results show that the cadmium concentrations of the soil and plant specimens taken from different places in different directions of the factory were higher than in the control areas. The physical examination of subjects did not reveal results different from those of the control group except for the diagnosis of contact dermatitis. The analysis of venous blood samples showed that cadmium concentrations were found to be within the reference values given for both groups, but higher in the subjects (p<0.001). According to the results of patch tests, sensitivity to cadmium was found to be more frequent for the subject group than the control group (p<0.05). Those results show that, although clinical tools revealed no toxic effects for the subject, except contact dermatitis, the cement plant increases cadmium pollution on the surrounding environment.  相似文献   
689.
Ashek A  Lee C  Park H  Cho SJ 《Chemosphere》2006,65(3):521-529
In the present study we have performed comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) on structurally diverse ligands of Ah (dioxin) receptor to explore the physico-chemical requirements for binding. All CoMFA and CoMSIA models have given q(2) value of more than 0.5 and r(2) value of more than 0.84. The predictive ability of the models was validated by an external test set, which gave satisfactory predictive r(2) values. Best predictions were obtained with CoMFA model of combined modified training set (q(2) = 0.631, r(2) = 0.900), giving predictive residual value = 0.02 log unit for the test compound. Addition of CoMSIA study has elucidated the role of hydrophobicity and hydrogen bonding along with the effect of steric and electrostatic properties revealed by CoMFA. We have suggested a model comprises of four structurally different compounds, which offers a good predictability for various ligands. Our QSAR model is consistent with all previously established QSAR models with less structurally diverse ligands.  相似文献   
690.
Journal of Polymers and the Environment - This paper presents the effects of silane coupling agent, which includes interfacial adhesive strength, water treatment, polymer composites and coatings...  相似文献   
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