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排序方式: 共有1353条查询结果,搜索用时 78 毫秒
871.
Analysis of driver injury severity levels at multiple locations using ordered probit models 总被引:4,自引:0,他引:4
Abdel-Aty M 《Journal of Safety Research》2003,34(5):597-603
Problem: The occurrence and outcome of traffic crashes have long been recognized as complex events involving interactions between many factors, including the roadway, driver, traffic characteristics, and the environment. This study is concerned with the outcome of the crash. Method: Driver injury severity levels are analyzed using the ordered probit modeling methodology. Models were developed for roadway sections, signalized intersections, and toll plazas in Central Florida. All models showed the significance of driver's age, gender, seat belt use, point of impact, speed, and vehicle type on the injury severity level. Other variables were found significant only in specific cases. Results: A driver's violation was significant in the case of signalized intersections. Alcohol, lighting conditions, and the existence of a horizontal curve affected the likelihood of injuries in the roadway sections' model. A variable specific to toll plazas, vehicles equipped with Electronic Toll Collection (ETC), had a positive effect on the probability of higher injury severity at toll plazas. Other variables that entered into some of the models were weather condition, area type, and some interaction factors. This study illustrates the similarities and the differences in the factors that affect injury severity between different locations. 相似文献
872.
Ahmed Irfan Socci Claudio Pretaroli Rosita Severini Francesca Deriu Stefano 《Environment, Development and Sustainability》2022,24(1):426-453
Environment, Development and Sustainability - In August and October 2016, and January 2017, Central Italy was shaken by four strong earthquakes followed by other earthquake swarms. These disruptive... 相似文献
873.
Chentouf Mohammed Allouch Mohamed 《Environment, Development and Sustainability》2022,24(9):10945-10974
Environment, Development and Sustainability - Energy security is a multi-dimensional concept that is gaining a growing interest worldwide for studying the sustainability of a given energy sector.... 相似文献
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876.
Saima Noor Shamaila Sajja Sajjad Ahmed Khan Leghari Cristina Flox Saeed Ahmad 《环境科学学报(英文版)》2021,33(10):107-119
The promising solar irradiated photocatalyst by pairing of bismuth oxide quantum dots (BQDs) doped TiO2 with nitrogen doped graphene oxide (NGO) nanocomposite (NGO/BQDs-TiO2) was fabricated. It was used for degradation of organic pollutants like 2,4-dichlorophenol (2,4-DCP) and stable dyes, i.e. Rhodamine B and Congo Red. X-ray diffraction (XRD) profile of NGO showed reduction in oxygenic functional groups and restoring of graphitic crystal structure. The characteristic diffraction peaks of TiO2 and its composites showed crystalline anatase TiO2. Morphological images represent spherical shaped TiO2 evenly covered with BQDs spread on NGO sheet. The surface linkages of , , and vibrational modes are observed by Fourier transform infrared spectroscopy (FTIR) and Raman studies. BQDs and NGO modified TiO2 results into red shifting in visible region as studied in diffused reflectance spectroscopy (DRS). NGO and BQDs in TiO2 are linked with defect centers which reduced the recombination of free charge carriers by quenching of photoluminescence (PL) intensities. X-ray photoelectron spectroscopy (XPS) shows that no peak related to in NGO/BQDs-TiO2 is observed. This indicated that doping of nitrogen into GO has reduced some oxygen functional groups. Nitrogen functionalities in NGO and photosensitizing effect of BQDs in ternary composite have improved photocatalytic activity against organic pollutants. Intermediate byproducts during photo degradation process of 2,4-DCP were studied through high performance liquid chromatography (HPLC). Study of radical scavengers indicated that has significant role for degradation of 2,4-DCP. Our investigations propose that fabricated nanohybrid architecture has potential for degradation of environmental pollutions. 相似文献
877.
Haeba MH Mohamed AI Mehdi AW Nair GA 《Journal of environmental biology / Academy of Environmental Biology, India》2002,23(3):231-237
Non-lethal dose of 70% ethanol extract of the Nerium oleander dry leaves (1000 mg/kg body weight) was subcutaneously injected into male and female mice once a week for 9 weeks (total 10 doses). One day after the last injection, final body weight gain (relative percentage to the initial body weight) had a tendency, in both males and females, towards depression suggesting a metabolic insult at other sites than those involved in myocardial function. Multiple exposure of the mice to the specified dose failed to express a significant influence on blood parameters (WBC, RBC, Hb, HCT, PLT) as well as myocardium. On the other hand, a lethal dose (4000 mg/kg body weight) was capable of inducing progressive changes in myocardial electrical activity ending up in cardiac arrest. The electrocardiogram abnormalities could be brought about by the expected Na+, K(+)-ATPase inhibition by the cardiac glycosides (cardenolides) content of the lethal dose. 相似文献
878.
Mohamed A. Okbah Maie I. El-Gammal Mahmoud S. Ibrahim Yousef A. A. Waheshi 《Chemistry and Ecology》2020,36(3):236-255
ABSTRACTThe present study was performed to investigate surface sediment samples from Lake Edku of the Nile Delta Lagoons, Egypt. The Lake is important for fishing in the region. The importance of research is to understand the mobility and bioavailability of each studied metal. The study was carried out on 10 sampling sites during 2017. The sediments were subjected to the technique of sequential extraction to examine the chemical forms of some trace metals (Fe, Mn, Zn, Cu, Pb and Ni). Five stage extractions were done as the following order: soluble and exchangeable, carbonate, iron and manganese oxides, organic matter fraction and residual fraction. Attained results from the five fractions showed variations in the concentrations of metal contents of different sites under study. The overall metal concentrations (%) in the initial four extractable fractions (exchangeable, carbonate, oxides and organic matter fractions) were assessed to configure the mobility of each studied metal. The risk assessment code (RAC) represents the summation of exchangeable and carbonate fractions, it was between low and medium risk for aquatic environment. The range percentage of RAC for the metals was in the following order: 1.8–13, 4–23.5, 15–26, 5.7–19.5, 9–25 and 4.8–18.2 for Fe, Mn, Zn, Cu, Pb and Ni, respectively. Approximately 30% of the total copper was associated to the organic fraction, which may represent a high mobility of copper in these sediments. The highest mobility of metals in the sediments could be confirmed by its bioavailability factor (BF), which was within the ranges of 0.32–0.61, 0.36–0.59, 0.64–0.83, 0.36–0.72, 0.37–0.62 and 0.52–0.78 for Fe, Mn, Zn, Cu, Pb and Ni, respectively. The BF exhibited the following order: Zn > Ni > Cu > Pb ≈ Mn?>?Fe. The high levels of BF for the studied metals may represent the potentiality for toxic metals to be easily released into the aquatic environment. 相似文献
879.
Removal of basic dye from waste-water using silica as adsorbent 总被引:1,自引:0,他引:1
The kinetics of removal of Basic Blue 3 from a textile effluent was studied using silica as an adsorbent. The adsorption was found to follow a first-order process. The influences on the rate of adsorption of various factors, such as temperature, concentration of dye solution, pH of the system and the amount of adsorbent have been investigated. On the basis of the isotherm studies, the various thermodynamical parameters have been calculated. The effect of electrolytes and surfactants has also been seen on the removal of the dye from the waste-water. 相似文献
880.
Mohamed El Esawey Caitlin Sowers Joy Sengupta Raoul Jain 《Traffic injury prevention》2019,20(2):220-225
Objective: The objective of this study was to evaluate the safety effectiveness of cable barrier systems installation on rural highway sections in British Columbia, Canada.Methods: Data on police-attended serious collisions (injury?+?fatality) on a number of rural highway sections in British Columbia, Canada, were used in the analysis. An empirical Bayes (EB) approach was employed to ensure that the evaluation results were reliable and to account for the regression to the mean artifact. Safety performance functions (SPFs) were developed using data collected at similar sites. For both median cable barrier (MCB) and roadside cable barrier (RCB) sections, the evaluation was undertaken using all serious collisions, truck serious collisions, and off-road serious collisions.Results: For MCB sections, the evaluation results showed statistically significant reductions of 21.7, 53.8, and 34.8% in all serious collisions, truck serious collisions, and off-road left (ORL) combined with head-on (HO) serious collisions. For RCB sections, statistically significant reductions of 74.7, 100, and 100% were found in all serious collisions, truck serious collisions, and off-road right (ORR) serious collisions, respectively. The impact of the after period on the evaluation results was explored. It was found that the changes in safety become more stable using an after period of 2–5 years.Conclusions: Cable barriers were successful in reducing the frequency of serious collisions on provincial highways in British Columbia. 相似文献