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Improving outdoor air quality based on building morphology: Numerical investigation

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Frontiers of Architectural Research 2020年第2期 319-334页

作者： Asmaa Mohammed Hassan ashraf abdel fatah el mokadem Naglaa Ali Megahed Osama Mahmoud Abo eleinen Architecture and Urban Planning Department Faculty of Engineering Port Said University

Due to rapid urbanization around the world, high concentrations of vehicular pollutants have deteriorated the outdoor air quality, which can affect the physical and psychological well-being of humans. Numerous strategies have been proposed to overcome these harmful impacts by improving the dispersion of air pollutants. Consequently, a question arises regarding the potential effects of building morphology on the dispersion of pollutants. Subsequently, transient three-dimensional Computational Fluid Dynamics(CFD) simulations are performed to examine the effect of building morphology on PM10dispersion. eleven cases with various prototypes and morphological methods are compared with a simple building form to identify the patterns of PM10dispersion within a given time sequence under a prevailing inflow condition. The results indicate that the different designs of building morphology with varying Relative compactness(RC) indicator highlight the importance of considering morphological factors to improve outdoor air quality. In addition, the proposed prototypes can reduce PM10concentrations by approximately 30%-90% at specific points in the studied time sequence. In particular, the vertical, horizontal, and grid folded prototypes can be considered more effective as an approximate decrease between 70% and 90% in PM10concentrations is observed,which reflects the influence of building morphology on improving outdoor air quality.

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Astrophysical parameters of ten poorly studied open star clusters

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Research in Astronomy and Astrophysics 2012年第1期12卷 75-83页

作者： ashraf Latif Tadross Reda el-Bendary Anas Osman Nader Ismail abdel Aziz Bakry National Research Institute of Astronomy & Geophysics Faculty of Science Al-Azhar University

We present the fundamental parameters of ten open star clusters, nominated from Kronberger et al. who presented some newly discovered stellar groups on the basis of the Two Micron All Sky Survey photometry and Digitized Sky Survey visual images. Star counts and photometric parameters （radius, membership, distance, color excess, age, luminosity function, mass function, total mass, and dynamical relaxation time） have been determined for these ten clusters for the first time. In order to calibrate our procedures, the main parameters （distance, age, and color excess） have been reestimated for another five clusters, which are also studied by Kronberger et al.

关键词： Galaxy: open clusters and associations: general-- stars: luminosity func-tion mass function -- catalogs surveys -- infrared: stars

IL28B polymorphism and cytomegalovirus predict response to treatment in Egyptian HCV type 4 patients

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World Journal of Gastroenterology 2013年第2期19卷 290-298页

作者： Mostafa K el Awady Noha G Bader el Din ashraf Tabll Yaser el Hosary ashraf O abdel Aziz Hesham el Khayat Mohsen Salama Tawfeek H abdelhafez Department of Microbial Biotechnology National Research CenterCairoGiza 12622Egypt Department of Internal Medicin National Research CenterCairoGiza 12622Egypt Department of Tropical Medicine Cairo UniversityGiza 12622Egypt Theodor Bilharz Research Institute Giza 12622Egypt National Liver Institute Shebeen El Kom 32512Egypt

AIM:To test whether the status of positive cytomegalovirus(CMV) DNA detection adds to the predictive value of IL28B and to further categorize C/T allele ***:This study included 166 chronic hepatitis C(CHC) patients who received combined interferon and ribavirin therapy for 48 wk,84 spontaneous hepatitis C virus(HCV) resolvers who were positive for IgG anti-HCV antibody and negative for HCV RNA,and 100 healthy subjects who were negative for both HCV antibodies and RNA as *** DNA from peripheral blood was used for IL28B rs.12979860 single nucleotide polymorphism(SNP) and CMV DNA detection.A 139 bp fragment containing IL28B SNP was amplified in all subjects by polymerase chain reaction using a specifically designed *** the IL28B rs.12979860 SNP was detected by restriction fragment length polymorphism(RFLP) *** presence of CMV DNA was tested by amplification of the gB1 gene using nested polymerase chain *** role of CMV and IL28B rs.12979860 SNP genotypes in determining the response rate to combined interferon therapy and clinical status of patients were statistically ***:Current data showed that 67% of patients carrying the IL28B 12979860 C/C allele had a sustained viral response(SVR) while the genotypes C/T and TT were associated with lower SVR rates,50% and 48%,*** rates for the C/C allele were lower than other HCV genotypes and/or other *** CC was associated with the response to interferon(P = 0.025).Genotype C/C was reduced from 48% in controls to 14% in CHC patients suggesting its protective role against progression to *** majority of spontaneously cleared subjects(86%) were C/C,confirming its protective *** C/T allele was present in 71% of CHC patients compared with 38% of controls,so the use of IL28B SNP genotyping only in these patients may be of little value as a predictor of *** reactivation occurred in 40% of CHC ***-infection with

关键词： Hepatitis C Interleukin 28B Genetic polymorphisms Human cytomegalovirus Spontaneous clearance

Dolomite apatite separation by amphoteric collector in presence of bacteria

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Journal of Central South University 2013年第6期20卷 1645-1652页

作者： elmahdy Ahmed el-Mofty Salah abdel-Khalek Mohamed abdel-Khalek Nagui el-MidanyAyman Central Metallurgical Research and Development Institute Mining Petroleum and Metallurgical Engineering DepartmentCairo University

Bioflotation represents one of the growing trends to enhance the selectivity of conventional flotation processes. It utilizes the micro-organisms to replace or to interact with the chemical reagents to increase the gap between surface properties of similar minerals and to enhance the separation selectivity. In this work, dolomite-phosphate separation was investigated using amphoteric collector （dodecyl-N-carboxyethyl-N-hyroxyethyl-imidazoline） in presence of bacteria. Two types of bacteria, Corynebacterium- diphtheriae-intermedius （CDI）, and Pseudomonas aeruginosa （PA）, were used. The collector-bacteria interaction was characterized by Fourier transform infra-red （FTIR）, frothing height and Zeta potential. The results show that the collector-bacteria interaction improves the flotation selectivity. Although, the PA positively affects the separation results, the CDI cannot lower the MgO to less than 1%. A phosphate content of 0.7% MgO and 31.77% P205 with a recovery of 68% at pH 11, 3.0 kg/t amphoteric collector, 4× 10^7 cells of PA is obtained.

关键词： dolomite phosphate amphoteric collector bacteria bio-flotation carbonate minerals

Modeling and Simulation of Nanotechnology Based Tag Antennas

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材料科学与工程（中英文版） 2011年第1期5卷 94-102页

作者： ashraf Shamseldin Yahia Nashwa Mohamed Shaalan Mostafa abdel fatah el-Aasser Mohamed Husseinabdel Razik electronics Group Physics Department Faculty of Science Ain Shams University Cairo 11566 Egypt

Simulation of electromagnetic Radiation Patterns of Microstrip Antennas in RFID Systems

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材料科学与工程（中英文版） 2011年第3期5卷 354-361页

NANOPOROUS MATERIALS BASED ON SPIROKETAL AND SPIROTHIOKETAL POLYMERS FOR SEPARATING METHANOL-TOLUENE MIXTURE

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Chinese Journal of Polymer Science 2011年第4期29卷 450-455页

作者： Hamada Hamada abdel-Razik Zeinhom Mohamed el-Bahy Chemistry Department Faculty of Science and Education(Alkhurma Branch)Taif UniversitySaudi Arabia

Organic microporous materials based on spiroketal and spirothioketal polymers were synthesized through 1,3- dioxol-forming polymerization reaction between pentaerythritol or pentaerythritol tetrathiol and different types of cyclohexa- 1,4-dione derivatives. The structure of the prepared polymers was confirmed by NMR spectroscopy and molecular mass measurements. Nitrogen adsorption/desorption isotherms of the prepared polymers show a large amount of nitrogen adsorbed at low relative pressure indicating microporosity. These polymers have Brunauer Emmitt and Teller （BET） surface areas in the range from 492 （m^2g^-1） to 685 （m^2 g^-1）. The prepared polymers were found to be useful for pervaporation separation of methanol-toluene mixture with a separation factor up to 12.5 and fluxes, varying between 6.7×10-3 kg/（m^2 h） and 13.4 × 10^-3 kg/（m^2 h）.

关键词： Spiroketal polymers Nanoporous materials Separation membranes.

Effect of Heat Input on the Microstructure and Properties of Dissimilar Weld Joint Between Incoloy 28 and Superaustenitic Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2014年第2期27卷 259-266页

作者： M.S.abdel Rahman N.A.abdel Raheem M.R.el Koussy Department of Metallurgy Faculty of EngineeringCairo University

Abstract This work focuses on studying the effect of welding heat input within the range from 1 to 5 kJ/mm on the microstructure and the corresponding mechanical and corrosion properties of dissimilar joint between superaustenitic stainless steel （UNS S31254） and Incoloy 28 （UNS N08028）. The two materials were butt-welded with ER NiCrMo3. The metallurgical changes associated with welding of SASS and Incoloy 28 were studied using optical microscope, SEM, and EDX. The mechanical and corrosion properties were investigated using tensile test, Vickers hardness test, and pitting and crevice corrosion tests. The weld metal microstructure showed precipitates with needle-like shape at 3 and 5 kJ/mm. Also, the microstructure showed unmixed zone （UMZ） at the fusion line of both SASS and Incoloy 28 sides at all the investigated heat inputs. The Mo microsegregation within UMZ at Incoloy 28 side increased as the heat input increased from 1 to 5 k J/ram but that in SASS increased with increasing heat input from 1 to 3 kJ/mm and then decreased with increasing from 3 to 5 kJ/mm. The ultimate tensile strengths for all specimens at all the investigated heat inputs are acceptable. The average hardness noticeably changed in weld metal as the heat input increased from 1 to 5 kJ/mm. Other zones such as HAZ or UMZ did not demonstrate marked changes in the average hardness. The pitting and crevice corrosion rates of the weld joint were found significant at l and 3 kJ/mm but insignificant at 5 kJ/mm according to ASTM G48.

关键词： Superaustenitic Incoloy 28 Welding Heat input Unmixed zone Microsegregation Corrosion

Performance Evaluation and Design of RO Desalination Plant: Case Study

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Journal of Geoscience and Environment Protection 2016年第2期4卷 53-63页

作者： Mona A. abdel-fatah Ayman el-Gendi Fatma Ashour Department of Chemical Engineering & Pilot Plant National Research Center Giza Egypt Department of Chemical Engineering Faculty of Engineering Cairo University Giza Egypt

The aim of this paper is to design a water desalination plant using Reverse Osmosis membrane to treat salt water to be usable for drinkable, domestic, industrial or agricultural uses. RO unit is designed to conservative standards for versatility in the event of feed water quality variations. The design includes a feed water flush cycle to minimize membrane fouling and piping corrosion during shutdown. The system will be all appropriate controls and instrumentation for automatic operation. All system components are available and of heavy duty industrial design and fabricated with the highest quality workmanship. Quality control will be maintained throughout all manufacturing processes. The system will produce permeate water minimum of 3600 m3/day with a quality of approximately 100 ppm total dissolved solids (TDS) when operating on well feed water with a 10,000 ppm TDS and a temperature of 25 - 30 degrees C. The design permeate recovery is 50%;and energy recovery device which saves $30,556.28/year.

关键词： Desalination Brackish Water RO Design Unit Energy Recovery Systems