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531.
Sheikh Imran Uddin Ahmed 《环境质量管理》2019,29(2):51-55
This study reports the probability of increased mortality of people within the political border of Bangladesh due to the emission of fine particulate matter with diameters of 2.5 microns or less (PM2.5) from the Matarbari coal power plant (MCPP). A Gaussian plume dispersion model has been used for this estimation. The PM2.5 emission rate data are unavailable as the construction of MCPP is still in its initial stage; therefore, the anticipated PM2.5 emission rate has been estimated based on data from a number of coal‐fired power plants in India and China. To make this study more meaningful, two different emission rates have been considered representing the best‐case and worst‐case scenarios. In both cases, the intake fraction has been found to be 0.12×10?2, and the value of relative risk varies between 1.134 and 1.374, respectively. Finally, it is estimated that approximately 11.5 million people inside Bangladesh will be exposed to the PM2.5 emission from MCPP, and between 7,667 and 17,675 people will experience premature death every year. 相似文献
532.
Ahmed E. Awadallah Ateyya A. Aboul-Enein Abdellatif H. Mahmoud Sayed S. Abd El Rehim Ahmed K. El-Ziaty Ahmed K. Aboul-Gheit 《International Journal of Green Energy》2018,15(10):568-576
Zirconia-magnesia supported cobalt catalysts with various Zr/Mg atomic ratios were prepared and evaluated for non-oxidative catalytic decomposition of methane to produce COx-free hydrogen and carbon nanotube. The catalytic performance of the catalysts was performed in a continuous fixed bed flow reactor at 700°C under atmospheric pressure. The fresh and spent catalysts were characterized by XRD, TPR, BET, TEM, and Raman spectroscopy. The results showed that the change in Zr/Mg ratio of the mixed oxide support has a significant effect on the catalytic performance of the active Co metal. The catalyst 30%Co/Zr0.8Mg0.2 showed the highest activity and stability within the used series of catalysts with hydrogen yield reached up to 79%. Both Co/Mg1.0 and Co/Zr1.0 showed poor stability due to strong Co-Mg interaction and aggregation of Co species on Zr support, respectively. All catalysts produced mainly MWCNTs with different diameters depending on the Zr/Mg ratio. The outer diameter increased with increasing Zr content in the catalyst due to the enlargement of the particle size of cobalt as a result of aggregation. 相似文献
533.
Ahmed I. El-Seesy Hamdy Hassan Latif Ibraheem Manzoore Elahi M Soudagar 《International Journal of Green Energy》2020,17(12):793-804
ABSTRACT The main challenge of utilizing ethanol in diesel engines in blending mode is the phase separation issue. Therefore, an attempt has been performed to enhance the stability feature of ethanol/Jatropha biodiesel (JME) blends by using n-butanol as co-solvent. The 10% by volume of n-butanol is added to the mixtures of 10% and 20% ethanol and 70% and 80% JME, which is denoted as JME10Bu10E and JME10Bu20E, respectively. The phase stability of the evaluated fuels is examined employing visual approach and Thermogravimetric analysis. These methods confirm that there is no phase separation for more than 2 months under ambient conditions. Then, the combustion and emission features are investigated utilizing a diesel engine run with different loads and constant speed. The findings demonstrate that the pmax. and HRR are increased by adding ethanol. The ignition delay is extended with the addition of ethanol while the combustion period is almost the same. The bsfc is decreased by adding ethanol compared to JME fuel. The CO, UHC, and NOx formations are reduced markedly by 40%, 40%, and 40%, respectively, with adding ethanol. Finally, using n-butanol and JME as co-solvents with ethanol supports the growth of renewable energy in the CI engine. 相似文献
534.
Radwa A. El-Salamony Enas Amdeha Nagwa A. Badawy Salwa A. Ghoneim Ahmed M. Al-Sabagh 《毒物与环境化学》2018,100(2):143-156
Four composites of metal oxide doped with activated carbon with a metal oxide weight of 20% were prepared using mechano-mixing method. The nano-catalysts were characterized by N2-adsorption–desorption, X-ray diffraction analysis, transmission electron microscopy, Fourier-transform infrared spectroscopy, UV-diffuse reflectance, and photoluminescence spectroscopy. Photo-catalytic degradation of methylene blue dye under UV 254 nm and visible light was examined. In general, prepared catalysts are more active for degradation of dye under visible light than UV, reaching 96% within 180?min irradiation using the SnO catalyst. Photo-degradation of methylene blue followed pseudo first order reaction mechanism with a rate constant of 14.8?×?10?3?min?1, and the time required for removal of 50% of dye was 47?min. 相似文献
535.
Abboud IA 《Environmental geochemistry and health》2008,30(1):11-20
Due to the increase in the number of urinary calculi disease cases in Jordan, stone samples were collected from patients from
various Jordanian hospitals (Princes Basma (PBH), King Abdullah University (KAUH), Al-Basheer (ABH) and Al-Mafraq (AMH)).
This study concentrates on the effect of trace metals in patients of urinary calculi. Trace metals were detected in 110 urinary
calculi samples using X-ray fluorescence (XRF) and atomic absorption spectroscopy (AAS) techniques. Of the calculi examined,
21 were pure calcium oxalate (CaOax), 29 were mixed calcium oxalate/uric acid, 23 were mixed calcium oxalate/phosphate (apatite),
25 were phosphate calculi (apatite/struvite), five were mixed calcium oxalate monohydrate/struvite, four were urate calculi
(mixed ammonium acid urate/sodium acid urate) and three were pure cystine calculi. The concentration measurement of Ca and
other trace metals levels has been found useful in understanding the mechanism of stone formation and in evaluating pathological
factors. It has been found that Ca is the main constituent of the urinary calculi, especially those stones composed of calcium
oxalate and calcium phosphate. The concentration of most of the trace metals that were analyzed was (Ca = 48.18, Na = 1.56,
K = 0.9, Mg = 3.08, Fe = 1.17, Al = 0.49, Zn = 0.7, Cu = 0.19, Mn = 0.029, P = 10.35, S = 1.88, Sr = 0.306, Mo = 0.2, Cr = 0.146,
Co = 0.05, Ni = 0.014)%. In conclusion, metals concentration in Jordanian patient’s urinary calculi samples was higher than
its equivalents of other patients’. It has been noted that there is no concentration of toxic trace elements (like Li, V,
Pb, Cd, and As). Some heavy metals, however, were detected Mo, Cr, Co and Ni as traces. P and S ions are present in few calculi
stones as traces. 相似文献
536.
537.
Hubert J. Montas Rabi H. Mohtar Ahmed E. Hassan Farqad A. AlKhal 《Journal of contaminant hydrology》2000,43(3-4)
An optimization methodology for designing groundwater quality monitoring networks applicable to stochastic flow fields is presented and evaluated. The approach sets itself apart from previous techniques by incorporating the time dimension directly into the objective function. This function is extremized using a directed partial enumeration strategy guided by physical considerations related to transport processes. The result is a set of monitoring well locations and a sampling schedule that minimizes plume characterization error while satisfying constraints on the maximum number of wells and allowable number of active wells. The method is evaluated using hypothetical plumes with varying degrees of heterogeneity. Results indicate that the proposed approach is successful in generating near-optimal sampling networks that satisfy all imposed constraints. Monitoring networks with as little as three active wells and a total of 12 wells are found to provide adequate plume characterization for low toxicity contaminants. 相似文献
538.
Akther Tanzina Ahmed Morshad Shohel Mohammad Ferdousi Farhana Khanom Salam Abdus 《Environmental science and pollution research international》2019,26(6):5475-5484
Environmental Science and Pollution Research - Real-time particulate matters (PM1, PM2.5, PM4, PM7, PM10, and TSP) with AEROCET 531S (USA), gaseous pollutants (NO2 and TVOC) with Aeroquel 500 gas... 相似文献
539.
Ahmed F. El-Aswad Maher I. Aly Mohamed R. Fouad Mohamed E. I. Badawy 《Journal of environmental science and health. Part. B》2019,54(6):475-488
The behavior of chlorantraniliprole (CAP) and dinotefuran (DNF) insecticides was investigated in clay loam soil, a common type of the Egyptian soil. Effect of temperature, pH and particle size of the soil on the adsorption process was studied. Adsorption isotherm by bulk soil and its constituents; humic acid (HA), clay, silt and sand fractions was measured using batch equilibration technique. The results showed that the adsorption of the insecticides tested was significantly affected by the temperature and was a spontaneous interfacial process in the soil. Freundlich model accurately predicted the adsorption behavior of both insecticides. The interaction between soil and insecticides was endothermic and the highest adsorption for CAP and DNF was obtained at pH 9. However, the effect of pH on the adsorption of DNF was lower than that of CAP. Sorption of CAP and DNF on HA fraction was significantly greater than on clay fraction and bulk soil. In addition, the adsorption was significantly increased with particle size decrease. It could be inferred that the adsorption of CAP and DNF on clay loam soil was physical in nature and greatly influenced by the soil components, pH and temperature. 相似文献
540.
Ahmed Belgacem Rachid Rebiai Hocine Hadoun Sihem Khemaissia Mohamed Belmedani 《Environmental science and pollution research international》2014,21(1):684-694
In this study, activated carbon was prepared from waste tire by KOH chemical activation. The pore properties including the BET surface area, pore volume, pore size distribution, and average pore diameter were characterized. BET surface area of the activated carbon was determined as 558 m2/g. The adsorption of uranium ions from the aqueous solution using this activated carbon has been investigated. Various physico-chemical parameters such as pH, initial metal ion concentration, and adsorbent dosage level and equilibrium contact time were studied by a batch method. The optimum pH for adsorption was found to be 3. The removal efficiency has also been determined for the adsorption system as a function of initial concentration. The experimental results were fitted to Langmuir, Freundlich, and Dubinin–Radushkevich (D-R) isotherm models. A comparison of best-fitting was performed using the coefficient of correlation and the Langmuir isotherm was found to well represent the measured sorption data. According to the evaluation using the Langmuir equation, the saturated monolayer sorption capacity of uranium ions onto waste tire activated carbon was 158.73 mg/g. The thermodynamic equilibrium constant and the Gibbs free energy were determined and results indicated the spontaneous nature of the adsorption process. Kinetics data were best described by pseudo-second-order model. 相似文献