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Study of Luminous Emission from a Coaxial Plasma Discharge Device in the Presence of External Transverse Magnetic Field

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Energy and Power Engineering 2011年第4期3卷 444-449页

作者： tarek M. Allam Hanaa A. el-Sayed Hanaa M. Soliman 不详

The experimental investigations in this paper are focused on the study of luminous radiation emission from coaxial plasma discharge device and the effect of applied transverse magnetic field Btr on it. The experiment was done in (1.5 KJ - 10 KV) coaxial plasma discharge device. The discharge is operated in Nitrogen gas at pressures from 1 to 2.2 torr. Helmholtz magnetic coils are placed outside the coaxial electrodes with its axis at a distance = 3 cm from the coaxial electrodes muzzle, then Btr with a maximum induction ≈ 0.85 T is applied perpendicularly to the expanded plasma from the coaxial electrodes muzzle. The diagnostics used in the measurements include a Rogowsky coil and a photomultiplier tube equipped with light collimator. The experimental results showed that the maximum intensity of luminous radiation is detected at axial distance (side view) z = 8 cm and gas pressure, P = 2.2 torr. It also showed that the maximum value of axial luminous plasma zone velocity = 2.383 × 106 cm/s at z = 11 cm and P = 1.4 torr. In mode of presence of external Btr, the investigations have shown that, at P = 1.4 torr the maximum intensity of luminous radiation (detected at end-view position) is reduced by 17%, the full width at half maximum, FWHM of luminous radiation signal is increased by 40 times, while the luminous radiation signal is delayed by ta = 438 μs. In two modes of operation ta and FWHM have approximately a minimum values at P = 1.4 torr.

关键词： Coaxial Discharge Luminous Radiation Transverse Magnetic Field Energy Losses

配方对富燃复合推进剂力学性能影响的实验研究(英文)

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含能材料 2015年第8期23卷 802-806页

作者： tarek M elhedery 梁国柱北京航空航天大学宇航学院北京100191

为实验研究推进剂配方对基于端羟基聚丁二烯粘结剂(HTPB)/过氯酸铵氧化剂(AP)/铝粉燃料(Al)的富燃复合推进剂力学性能的影响。综合混合、浇铸和固化影响因素,制备了11种不同推进剂试样10 kg,并在25℃下采用Zwick试验机以50 mm·min-1的... 详细信息

为实验研究推进剂配方对基于端羟基聚丁二烯粘结剂(HTPB)/过氯酸铵氧化剂(AP)/铝粉燃料(Al)的富燃复合推进剂力学性能的影响。综合混合、浇铸和固化影响因素,制备了11种不同推进剂试样10 kg,并在25℃下采用Zwick试验机以50 mm·min-1的速率对标准JANNAF试件进行了测试。结果表明,当粘结剂的含量从74.5%减小到34.5%、以AP和Al替代时,推进剂的应变减小,抗拉强度、杨氏模量和硬度增大。AP的颗粒尺寸和含量对推进剂的力学性能有影响,AP细颗粒可充当了活性的填充物并增强复合推进剂的力学性能,当AP颗粒的平均直径从55.9μm减小到9μm时,推进剂的抗拉强度、杨氏模量和硬度增大,应变减小,表明该类富燃复合推进剂力学性能主要受到粘结剂和AP平均颗粒尺寸的影响。

关键词：复合推进剂富燃推进剂力学性能 AP颗粒尺寸粘结剂

Cloning and characterization of 66 kDa streptavidin-binding peptides(SBP)of Pisum sativum *** specific to ***

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BIOCelL 2019年第3期43卷 155-166页

作者： MAHMOUD MOUSTAFA SAAD ALAMRI tarek TAHA ALI SHATI SULAIMAN ALRUMMAN MOHAMED ALKAHTANI Department of Biology College of ScienceKing Khalid University9004AbhaKingdom of Saudi Arabia Department of Botany Faculty of ScienceSouth Valley UniversityQenaEgypt Environmental Biotechnology Department Genetic Engineering and Biotechnology Research Institute(GEBRI)City of Scientific Research and Technological Applications(SRTA-City)New Borg El-Arab City21934AlexandriaEgypt

The aim of the current research was to clone and to characterize the partial 66 kDa streptavidin-binding peptide(SBP)found in the germinated embryos of Pisum sativum *** pea(*** ***)embryos possess prominent 66 kDa SBPs that gradually disappeared after few hours of germination in germinated embryos,but not in the *** total RNA was isolated from embryos of *** but could not be isolated from the *** partial nucleotides sequences of 66 kDa SBPs of embryonic stalk(*** ***)were cloned and identified using pMOSBlue vector.66 kDa(SBP)gene from the embryos of *** *** possesses 327 bp having an open reading frame(ORF)region in a part of the gene that encoded for 108 amino *** showed similarity among 66 kDa SBPs *** ***,with *** seed biotinylated protein(SBP65)and *** sbp65a mRNA with DNA distance matrix between 0.0094 to ***-TOF mass spectrometry analysis of 66 kDa(SBP)proteins showed it had similar short peptides to 19 proteins found in different organisms,especially Convicilin precursor,and the seed biotinylated protein in *** alignment results of both nucleotide sequences and amino acid residues either from cloning or MALDI-TOF-MS showed differences with related species,especially *** mRNA was found in the cotyledons during seeds germination,which means no metabolic activities and this part may act only as food reservoirs for growing newly embryos.

关键词： Cloning Embryo 66 kDa Pisum sativum Streptavidin-binding peptides(SBP)

Cutaneous leishmaniasis in Al Hassa, Saudi Arabia: Epidemiological trends from 2000 to 2010

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Asian Pacific Journal of Tropical Medicine 2013年第8期6卷 667-672页

作者： tarek Tawfik Amin Hamdan Ibrahim Al-Mohammed Feroze Kaliyadan Balghonaim Salah Mohammed King Faisal University Cairo University Vector Control Unit Preventive Medicine Department Local Health Directorate Al Hofuf Ministry of Health

Objective: To study epidemiological trends related to cutaneous leishmaniasis (CL) in Al Hassa, an endemic area in Saudi Arabia. Methods: This retrospective study included the spatial/ temporal analysis of the reported cases of CL using the available surveillance database for the disease at the regional Vector Control Unit, from 2000 to 2010. Results: The incidence of CL was declining at a stable rate especially during the last 3 years of the study (2008-2010). An interesting finding was the percentage of expatriates affected was increasing over the last 10 years compared to that of the Saudis. Conclusions: A definite declining trend in the incidence of CL was observed in Al Hassa. Further studies are warranted to assess whether special public health measures are needed for better control of CL in expatriate populations in Saudi Arabia.

关键词： Cutaneous leishmaniasis Epidemiology Saudi Arabia

Removing Iron Ions Contaminants from Groundwater Using Modified Nano-Hydroxyapatite by Nano Manganese Oxide

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Journal of Water Resource and Protection 2019年第6期11卷 789-809页

作者： Mohammed Abd-el-Aal Ahmed Ayash tarek Ahmed Seaf elnasr Madiha Hassan Soliman Sohag Company for Water and Waste Water Dar El Salam Sohag Egypt Chemistry Department Faculty of Science Al-Azhar University Assiut Egypt Chemistry Department Collage of Science Jouf University KSA Chemistry Department Faculty of Science Helwan University Cairo Egypt

In this article, we study modified nano-hydroxyapatite (HAp) by nano manganese oxide (Mn3O4) as adsorbent material to remove iron ions from groundwater. Different parameters were studied to option optimum conditions of removing such as contact time, pH, initial concentration, a dosage of adsorbent, agitation speed and temperature. Kinetics studies included first order (R2 = 0.915), pseudo-first order (R2 = 0.936), second order (R2 = 0.948), pseudo-second order (R2 = 0.995), elovich equation model (R2 = 0.977), intraparticle diffusion (R2 = 0.946), Natarajan and Khalaf (R2 = 0.915) were carried out, the obtained results revealed that the pseudo-second order is the best to describe the adsorption process because the correlation coefficient is approaching one (R2 = 0.995). Adsorption isotherm was calculated by using Freundlich, Langmuir and Temkin constants, adsorption capacity from Langmuir model was 0.606 mg/g. Thermodynamic parameters (ΔG, ΔH = ?51 KJ/mol, and ΔS = ?142 (KJ/mol)) for the adsorption process were also calculated and discussed.

关键词： Groundwater Adsorption Nano Materials Hydroxyapatite Manganese Oxide Iron Ions Kinetic Thermodynamic

Investigating Diesel Engine Performance and Emissions Using CFD

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Energy and Power Engineering 2013年第2期5卷 171-180页

作者： tarek M. Belal el Sayed M. Marzouk Mohsen M. Osman Department of Mechanical Engineer Alexandria University Alexandria Egypt Department of Mechanical Engineering Umm Al-Qura University Makka KSA

Fluid flow in an internal combustion engine presents one of the most challenging fluid dynamics problems to model. This is because the flow is associated with large density variations. So, a detailed understanding of the flow and combustion processes is required to improve performance and reduce emissions without compromising fuel economy. The simulation carried out in the present work to model DI diesel engine with bowl in piston for better understanding of the in cylinder gas motion with details of the combustion process that are essential in evaluating the effects of ingesting synthetic atmosphere on engine performance. This is needed for the course of developing a non-air recycle diesel with exhaust management system [1]. A simulation was carried out using computational fluid dynamics (CFD) code FLU- ENT. The turbulence and combustion processes are modeled with sufficient generality to include spray formation, delay period, chemical kinetics and on set of ignition. Results from the simulation compared well with that of experimental results. The model proved invaluable in obtaining details of the in cylinder flow patterns, combustion process and combustion species during the engine cycle. The results show that the model over predicting the maximum pressure peak by 6%, (p-θ), (p-v) diagrams for different engine loads are predicted. Also the study shows other engine parameters captured by the simulation such as engine emissions, fuel mass fraction, indicated gross work, ignition delay period and heat release rate.

关键词： Numerical Simulation Unsteady Flow Combustion Diesel Engine

Liuwei Dihuang, a traditional Chinese herbal formula, suppresses chronic inflammation and oxidative stress in obese rats

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Journal of Integrative Medicine 2014年第5期12卷 447-454页

作者： Benjamin Perry Junzeng Zhang tarek Saleh Yanwen Wang Aquatic and Crop Resource Development Life Sciences Branch National Research Council CanadaCharlottetown PE Canada C1A 4P3 Department of Biomedical Sciences University of Prince Edward IslandCharlottetown PE CanadaC1A 4P3 Department of Chemistry University of Prince Edward IslandCharlottetown PE Canada C1A 4P3

OBJECTIVE： To investigate the anti-inflammatory, anti-oxidative stress, and adipokine-ameliorating effects of Liuwei Dihuang （LWDH）, a traditional Chinese herbal formula, in obese rats. METHODS： After 2 weeks of acclimation with free access to regular rodent chow and water, obese-prone-caesarean-derived （OP-CD） rats were fed a modified AIN-93G diet containing 60% energy from fat. Treatment was performed twice daily by gavage feeding with 500, 1 500, or 3 500 mg/kg body weight LWDH suspended in water （n=12 rats per group）. Twelve obese-resistant-CD （OR-CD） rats were fed the atherogenic diet and gavaged with water, and served as the normal control. Blood biomarkers of inflammation, oxidative stress and adiponectin were measured post-sacrifice and used to determine the treatment effect of LWDH and assess the suitability of OR/OP-CD rats for studying these parameters. RESULTS： After 9 weeks of treatment, LWDH lowered serum C-reactive protein （CRP） and tumour necrosis factor-α （TNF-α） levels. Serum interleukin-6 （IL-6） levels showed a tendency towards reduction, but were not significantly different from the OP-CD control. Liver superoxide dismutase （SOD） activity was increased in response to all three doses of LWDH, while the levels of reduced （GSH） and oxidized glutathione （GSSG） and thiobarbituric acid reactive substances （TBARS） were unchanged. Serum adiponectin levels were increased in response to oral administration of LWDH at the dose of either 500 or 1 500 mg/kg body weight. In addition, comparisons between OR-CD and OP-CD rats revealed differential, and for some biomarkers, conflicting characteristics of high-fat diet-fed OP-CD rats in reference to obese human subjects in terms of inflammatory and oxidative stress biomarkers and circulating adiponectin levels. CONCLUSION： The results show, for the first time, the anti-inflammatory, anti-oxidative stress and adiponectin-ameliorating effects of LWDH in obese rats. The suitability of the OP-JOP-CD rat model as a res

关键词： durgs, Chinese herbal Liuwei Dihuang obesity inflammation oxidative stress adiponectin rats

Epidemiological Aspects of Intrafamilial Spread of HCV Infection in Egyptian Population: A Pilot Study

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Open Journal of Gastroenterology 2014年第5期4卷 228-236页

作者： Mahmoud el-Bendary Gamal Esmat Mustafa Neamatallah Emily Kamel tarek Besheer Hatem elalfy Maged el-Setouhy Dalia Omran Department of Community Environmental and Occupational Medicine Ain-Shams Faculty of Medicine Ain-Shams University Cairo Egypt Medical Biochemistry Department Mansoura Faculty of Medicine Mansoura University Mansoura Egypt Public Health & Preventive Medicine Department Mansoura Faculty of Medicine Mansoura University Mansoura Egypt Tropical Medicine & Hepatology Department Cairo Faculty of Medicine Cairo University Giza Egypt Tropical Medicine & Hepatology Department Mansoura Faculty of Medicine Mansoura University Mansoura Egypt

Aim: Liver disease is a leading cause of morbidity and mortality among Egyptians. The major cause is infection with HCV, with 70 000 up to 140 000 newly reported cases annually. The objectives of this study were to determine the prevalence of anti-HCV antibodies among household contacts of HCV index cases and to identify the possible risk factors of transmission of HCV among Egyptian families. Material and Methods: The present external pilot study (double centre study) was performed on a convenient sample of 125 index cases and their 321 household family contacts recruited from Mansoura & Cairo University where 2 questionnaires were used to collect data from the index & their related contacts. The all were exposed to clinical examinations, routine laboratory testing & screening for the prevalence of Anti-HCV antibodies. Results: The prevalence of anti-HCV seropositivity among household contacts of index cases was found to be 13.7% which husbands of female index cases ranked first followed by wives of male index cases (36.36% versus 17.86% respectively,

关键词： HCV Intrafamilial Transmission Epidemiology

Distribution of Different Organotin and Organolead Compounds in Sediment of Suez Gulf

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Journal of Environmental Protection 2011年第5期2卷 545-554页

作者： Mohamed A. Shreadah tarek O. Said Safaa A. Abd el Ghani Abd el Moniem M. Ahmed 不详

Organotin and organolead compounds were determined in sediments of the Suez Gulf The concentrations of Tributyltin (TBT) ranged from 0.27 to 2.77 with an average value of 1.37 μgg-1;dry wt. However, the concentrations of dibutyltin (DBT) ranged from 0.07 to 2.27 with an average value of 0.58 μgg-1;dry wt. A significant correlation was found between TBT and DBT with r = 0.82, (p = 0.05) indicating that the occurrence of DBT is mainly related to the degradation of TBT. Generally, the high concentration of TBT was attributed to shipping activity in harbours. In addition, Diphenyltin (DPhT) concentrations ranged from not detected to 2.09 with an average of 1.10 μgg-1 dry wt. Antifouling agents, industrial discharge and the influence of sewage discharge are the main sources of pollution by DPhT compounds in Suez Gulf. On the other side, organolead (OLC) concentrations ranged from 10.88 - 440.2 with an average of 168.7 ngg-1;dry wt. A significant setting of OLC recorded in sediments of Suez Gulf was mainly attributed to cars exhaust and/or spelling and direct evaporation of fuels.

关键词： Organotin Organolead Sediment Suez Gulf Egypt