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101.
Introduction: Restraint systems (seat belts and airbags) are important tools that improve vehicle occupant safety during motor vehicle crashes (MVCs). We aimed to identify the pattern and impact of the utilization of passenger restraint systems on the outcomes of MVC victims in Qatar.

Methods: A retrospective study was conducted for all admitted patients who sustained MVC-related injuries between March 2011 and March 2014 inclusive.

Results: Out of 2,730 road traffic injury cases, 1,830 (67%) sustained MVC-related injuries, of whom 88% were young males, 70% were expatriates, and 53% were drivers. The use of seat belts and airbags was documented in 26 and 2.5% of cases, respectively. Unrestrained passengers had greater injury severity scores, longer hospital stays, and higher rates of pneumonia and mortality compared to restrained passengers (P = .001 for all). There were 311 (17%) ejected cases. Seat belt use was significantly lower and the mortality rate was 3-fold higher in the ejected group compared to the nonejected group (P = .001). The overall mortality was 8.3%. On multivariate regression analysis, predictors of not using a seat belt were being a front seat passenger, driver, or Qatari national and young age. Unrestrained males had a 3-fold increase in mortality in comparison to unrestrained females. The risk of severe injury (relative risk [RR] = 1.82, 95% confidence interval [CI], 1.49–2.26, P = .001) and death (RR = 4.13, 95% CI, 2.31–7.38, P = .001) was significantly greater among unrestrained passengers.

Conclusion: The nonuse of seat belts is associated with worse outcomes during MVCs in Qatar. Our study highlights the lower rate of seat belt compliance in young car occupants that results in more severe injuries, longer hospital stays, and higher mortality rates. Therefore, we recommend more effective seat belt awareness and education campaigns, the enforcement of current seat belt laws, their extension to all vehicle occupants, and the adoption of proven interventions that will assure sustained behavioral changes toward improvements in seat belt use in Qatar.  相似文献   

102.
In the present study short-term (96 hr) toxicity of mercury in relation to water hardness (270 and 560 mg/l) and temperature (16 degrees C and 35 degrees C) to the fingerlings of Indian major carps, i.e. catla, rohu and mrigal has been evaluated using static bioassay. The LC5o indicates that both water hardness and temperature played significant role in mercury toxicity. The test fishes were found most resistant with water hardness of 560 mg/l at 16 degrees C as compared to that of water hardness of 560 mg/l at 35 degrees C and water hardness of 270 mg/l at both the temperatures, i.e. 35 and 16 degrees C. Whereas the order of relative sensitivities of these fishes for mercury ions were recorded as catla>rohu>mrigal. The safe concentrations of mercury were ranged in between 12.133 to 19.689 microg/l for catla; 64.039 to 82.555 microg/l for rohu and 73.510 to 89.585 microg/l for mrigal for both the water hardness and temperature.  相似文献   
103.
In this review a brief introduction to thiram (tetramethylthiuram disulfide; TMTD) pesticide has been given along with other applications. All the important methods available are systematically arranged and are listed under various techniques. Some of these methods have been applied for the determination of thiram in commercial formulations, synthetic mixtures in grains, vegetables and fruits. A comparison of different methods is the salient feature of this review.  相似文献   
104.
This paper presents the risk associated with the release of toxic chemicals from a manufacturing facility, following the State of California's approach to risk assessment. The facility emits five toxic substances from eight stacks. The building downwash is considered during dispersion calculations. The zone of impact, identified using a risk criteria (i.e. excess cancer risk of 10 in a million), is located in the southeast quandrant from the plant. The size of the impact area is 3.3 km2. The cancer and non-cancer effects are considered for chromium (VI), benzene, formaldehyde, gasoline vapors, methylene chloride, and selenium using the California Air Pollution Control Officers Association Guidelines. No significant non-cancer effects are found due to the emissions. The maximum calculated risk is 1.197×10-5 and is an extremely conservative value. Analysis shows that the use of realistic assumptions for exposure duration and unit risk factors during the risk calculations could reduce the zone of impact to 0 km2.  相似文献   
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To evaluate the complex interactions of various types of water systems, a water resource management agency is invariably involved in the preliminary step of reviewing the available quantitative methods for formulating interdisciplinary aspects of the water systems. With a view to supplement their efforts, an attempt is made in this paper to review briefly the major useful concepts and models which are intended to broaden the technical horizon of the professionals associated with the regional water resource management programs. Initially, various pathways of model building procedure are outlined. Then associated ecological, economic, social, political, technological and environmental models are discussed in light of some reported quantitative examples. With the understanding of the basic mechanics of these interdisciplinary models, the adequacy of these models and their applications can be examined by the concerned professionals to aid the decision making process for the specific water system in question.  相似文献   
107.
A research tool for modeling the reactive flow and transport of groundwater contaminants in multiple dimensions is presented. Arbitrarily complex coupled kinetic–equilibrium heterogeneous reaction networks, automatic code generation, transfer-function based solutions, parameter estimation, high-resolution methods for advection, and robust solvers for the mixed kinetic–equilibrium chemistry are some of the features of reactive flow and transport (RAFT) that make it a versatile research tool in the modeling of a wide variety of laboratory and field experiments. The treatment of reactions is quite general so that RAFT can be used to model biological, adsorption/desorption, complexation, and mineral dissolution/precipitation reactions among others. The integrated framework involving automated code generation and parameter estimation allows for the development, characterization, and evaluation of mechanistic process models. The model is described and used to solve a problem in competitive adsorption that illustrates some of these features. The model is also used to study the development of an in situ Fe(II)-zone by encouraging the growth of an iron-reducing bacterium with lactate as the electron donor. Such redox barriers are effective in sequestering groundwater contaminants such as chromate and TCE.  相似文献   
108.
This study was designed to determine the protective effects of zinc (Zn) using liver marker enzymes in the serum and liver along with hepatic elemental profile in lead (Pb)-treated protein-deficient (PD) Sprague–Dawley male rats. Zn in the form of zinc sulfate at a dose of 227?mg?L?1 in drinking water was administrated to control, PD as well as Pb-treated PD rats for 8 weeks. Pb treatment was given orally as lead acetate at a dose level of 100?mg?kg?1 body weight to control and PD rats. The effects of different treatments were studied on the activities of enzymes that included alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum. The status of different elements (Cl, K, Mn, Fe, Cu, Zn, Se, Rb, Pb) in liver was also studied. Rats given PD diet and Pb showed significant inhibition in serum ALP activity associated with significant elevation in both AST and ALT activities. Serum ALP activity showed a significant inhibition week 1 until week 8 in Pb-treated PD rats. In contrast, serum AST activity was elevated both at 3 and 8 weeks while serum ALT activity was elevated at 8 weeks in Pb-treated PD rats. Pb treatment to PD rats elevated hepatic ALP, AST and ALT activities but depressed hepatic AST. Zn supplementation to Pb-treated PD rats restored the altered enzyme activities. The levels of K, Fe, Cu, Zn, Se and Rb were altered in protein deficiency. Furthermore, treatment with Pb to these animals depressed the Cu levels. Zn treatment to Pb-treated PD animals tended to restore the levels of altered elements. Hence, the present study clearly suggests that Zn plays an important role in regulating the liver marker enzymes and essential elements under conditions of Pb toxicity and protein deficiency.  相似文献   
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110.
ABSTRACT: Waste waters from various operations at the Miami International Airport are characterized. Servicing, maintenance, overhauling, and washing of aircraft seem to be the most significant waste water producing operations. Pollutional constitutents commonly found in the airport wastes include acids, alkalis, detergents, oil, grease, and oxygen demanding substances. Phenols are of concern when stripping and repainting operations occur. Although most airport wastes may be treatable, a great reduction in influent load can be achieved by proper housekeeping methods.  相似文献   
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