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Effect of concrete buildings on the environmental neutron flux by using the reaction ^(197)Au (n,γ) ^(198)Au and extremely low level gamma ray spectroscopy

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Nuclear Science and Techniques 2004年第6期15卷 368-374页

作者： K. KOMURA N.K. ahmed A.h. EL-KAMEL A.M.M. YOUSEF Low Level Radioactivity Laboratory Kanazawa University Wake Tatsunokuchi Ishikawa 923-1224 JapanPhysics Department Faculty of Science South Valley University Kena EgyptPhysics Department Faculty of Science Assiut University Assiut EgyptPhysics Department Faculty of Science South Valley University Kena Egypt

The activation of gold by environmental neutrons through the reaction 197Au (n,γ) 198Au was used to study the effect of concrete buildings on the neutron flux, and to estimate the thermal neutron flux inside and outside these buildings. The results showed that three ceilings of thickness 34 g/cm2 decrease the fast neutrons to 26% from its original value. however, the same reinforced concrete decreases the slow neturon flux to only 62% of its original value. The thermal neutron flux at 283 m from the center of Training Reactor of Kinki University, was twice higher than the environmental neutron background.

关键词：金活性混凝土环境中子宇宙射线

Variation of environmental neutron flux with altitude and depth of both water and soil

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Nuclear Science and Techniques 2004年第4期15卷 248-256页

作者： K.KOMURA N.K.ahmed A.h.EL-KAMEL A.M.M.YOUSEF Low Level Radioactivity Laboratory Kanazawa UniversityWake TatsunokuchiIshikawa 923-1224JapanPlrysics DepartmentFaculty of Science.South Valley UniversityKenaEgyptPhysics DepartmentFaculty of ScienceAssiut UniversityAssiutEgyptPhysics DepartmentFaculty of Science.South Valley UniversityKenaEgypt

Applying the extreme low-level γ-ray spectroscopic analysis the environmental neutron flux is measured using different moderator construction and environment through the reaction 197Au (n, γ) 198Au. The contribution of thermal and resonance neutrons is separated using the cadmium difference technique, while fast neutrons are measured by the paraffin moderator. The results of altitude dependence of the neutron flux are discussed. The thermal neutron flux near the surface of sea water is less than its value at 100 cm over ground near sea water, while the value over the surfaces of fresh water is higher than that near the surface of sea water. Also the thermal neutron flux at 5 cm soil depth increases, then decreases to its original value at 10 cm depth and still constant until 25 cm, then decreases rapidly to reach 27% of its original value at 60 cm depth. The soil compositions, corresponding neutron temperatures and effective absorption cross sections of earth are the most effective factors on the equilibrium region of thermal neutrons in the ground.

关键词：环境中子流金活化作用 γ射线光谱学环境放射学水土壤

Mosquito autogeny in Aedes caspius （Diptera： Culicidae）： alterations of larval nourishments reservation upon bacterial infection

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Insect Science 2013年第4期20卷 472-484页

作者： Ashraf M. ahmed Zoology Department College of Science King Saud University SaudiArabia Zoology Department College of Science Minia UniversityEl-Minia Egypt

The present study recorded mosquito autogeny for the first time amongst Aedes caspius species in the Eastern region of Saudi Arabia. Laboratory rearing showed an obligatory autogenous species of Ae. caspius since it foregoes blood feeding during its first ovarian cycle, even in the presence of the hosts （CD mouse）, but produces its second egg batch only if ingested a blood meal. Both morphological and molecular identification confirmed that both autogenous and anautogenous strains belong to the same species of Ae. caspius. Data from biochemical analysis showed significant 2, 1.6, and 1.4 folds higher total carbohydrates, proteins, and lipids reserves respectively in the fourth larval instar of the autogenous strain compared to that of the anautogenous ones. In addition, exposing the fourth larval instars of autogenous strain to the infection stress by the mosquito larvicidal bacterium, Bacillus thuringiensis var kurstaki has significantly reduced total carbohydrates, proteins and lipids reserves by 29%, 35%, and 46%, respectively, at 12 h postinfection compared to those of uninfected ones. These reductions in nourishment reserves were more pronounced at 24 h postinfection in the case of proteins and lipids, but not carbohydrates. These results may indicate that bacterial infection is a health stress that significantly reduced nourishments reservation, which may interrupt the success of adult autogeny. however, the impact of infection-induced decline in larval nourishments reservation on successful adult autogeny is still to be investigated.

关键词： Aedes caspius anautogeny autogeny Bacillus thuringiensis nourishmentsreservation

助剂对甲烷干重整 Ni/γ-Al_2O_3催化剂性能的影响(英文)

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催化学报 2011年第10期32卷 1604-1609页

作者： ahmed S.A.AL-FATESh Anis h.FAKEEhA ahmed E.ABASAEED Chemical Engineering Department College of EngineeringKing Saud UniversityP.O.Box 800Riyadh 1142Saudi Arabia

The Ni catalysts supported on γ-Al2O3 were synthesized by an impregnation *** catalytic performance in methane dry reforming was *** reforming reactions were carried out in a microreactor using a CO2:Ch4 feed ratio of 1:1,a F/W = 2640 ml/(h·g),reaction temperatures between 500-850 ?C,and at atmospheric *** influence of Ca,Ce,and Zr promoters on catalyst stability,coke deposition,and the h2/CO ratio were also *** were analyzed using an online gas chromatograph equipped with a thermal conductivity *** spent and fresh catalysts were characterized by scanning electron microscopy and thermogravimetric *** was found that 3%Ni/γ-Al2O3 promoted with 0.15% Ce and 0.05% Ca gave the best performance and resulted in less coke *** highest Ch4 and CO2 conversion activities were found to be 94.1% and 98.3% at 850 ?C,*** tests were carried out for 130 h and this provided a h2 yield of 91%.Moreover,the amount of formed carbon was negligible and did not increase to more than 1.5 wt%.

关键词：稳定性合成气焦碳合成方法

hepatoprotective Effect of Camel Thorn Polyphenols in Concanavalin A-Induced hepatitis in Mice

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Chinese Journal of Integrative Medicine 2024年第12期30卷 1090-1100页

作者： Nageh ahmed El-Mahdy Thanaa ahmed El-Masry ahmed Mahmoud El-Tarahony .Fatemah AAlherz Enass Youssef Osman Department of Pharmacology and Toxicology Faculty of PharmacyTanta UniversityTanta 31527Egypt Department of Pharmaceutical Sciences College of PharmacyPrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia

Objective:To explore the prophylactic and therapeutic effects of Alhagi maurorum ethanolic extract(AME)in concanavalin A(Con A)-induced hepatitis(CIh)as well as possible underlying ***:Polyphenols in AME were characterized using high performance liquid chromatography(hPLC).Swiss albino mice were divided into 4 *** group received intravenous phosphate-buffered saline(PBS);Con A group received 40 mg/kg intravenous Con *** group administered 300 mg/(kg·d)AME orally for 5 days before Con A *** group received intravenous Con A then administered300 mg/kg AME at 30 min and 3 h after Con A *** 24 h of Con A injection,hepatic injury,oxidative stress,and inflammatory mediators were *** examination and markers of apoptosis,inflammation,and CD4^(+)cell infiltration were also ***:hPLC analysis revealed that AME contains abundant polyphenols with pharmacological constituents,such as ellagic acid,gallic acid,ferulic acid,methylgallate,and *** alleviated Con A-induced hepatic injury,as manifested by a significant reduction in alanine aminotransferase,aspartate aminotransferase and alkaline phosphatase(Phe antioxidant effect of AME was revealed by a significant reduction in oxidative stress markers(nitric oxide and malondialdehyde)and restored glutathione(Phe levels of proinflammatory cytokines(tumor necrosis factor-α,interferon-γ,and interleukin-6)and c-Jun N-terminal kinase(JNK)activity were reduced(Phistopathological examination of liver tissue showed that AME significantly ameliorated necrotic and inflammatory lesions induced by Con A(Phe expression of nuclear factor kappa B,pro-apoptotic protein(Bax),caspase-3,and CD4^(+)T cell hepatic infiltration(Phe expression of anti-apoptotic protein Bcl-2 was increased(Phas hepatoprotective and ameliorative effects in CIh mice

关键词： concanavalin A-induced hepatitis Alhagi maurorum ethanolic extract hepatoprotective effect

Waste heat Recovery from a Drier Receiver of an A/C Unit Using Thermoelectric Generators

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Energy Engineering 2023年第8期120卷 1729-1746页

作者： Ali Jaber Abdulhamed Aws Al-Akam ahmed A.Abduljabbar Mohammed h.Alkhafaji Energy Engineering Department Faculty of Engineering/AL-MussayibUniversity of BabylonHillaBabylonIraq Construction and Projects Department Al Iraqia UniversityBaghdadIraq Department of Electrical Engineering University of TechnologyBaghdadIraq

Thermoelectric generators(TEGs)are considered promising devices for waste heat recovery from various *** Seebeck effect can be utilized to generate power using the residual heat emitted by the filter dryer receiver(FDR)of an air conditioning(A/C)system,which would otherwise go to *** study aims to build a set of thermoelectric generators(TEG)to collect the waste heat of the FDR and generate low-power electricity.A novel electrical circuit with two transformers is designed and fabricated to produce a more stable voltage for operation and *** thermoelectric generator(TEGs)was installed on the FDR of the A/C *** test showed that climate conditions have a significant impact on the output power generated from the *** results showed that the peak voltage recorded in the current study is 5.2 V per day(wet,cold,and wind weather)with an output power of 0.2 *** values are acceptable for powering the load and charging a single battery with 3.5 V as the voltage increases battery 0.1 V/20 min charge.A case study of operating the emergency signs in a building was *** current heat recovery system is deemed to be easily installed and can be connected to a network of TEGs to produce more power.

关键词： Thermoelectric generator waste heat filter dryer receiver air conditioning heat recovery

Bilateral same-session intravitreal injections of antivascular endothelial growth factors

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International Journal of Ophthalmology(English edition) 2014年第6期7卷 1017-1021页

作者： Nakhleh E.Abu-Yaghi ahmed N Shokry Rami h Abu-Sbeit Department of Ophthalmology Faculty of Medicinethe University of Jordan

AIMTo document the indications, safety and possible complications of bilateral same-session intravitreal anti-vascular endothelial growth factor (VEGF) injections performed in the ophthalmic operating room.

关键词： anti-vascular endothelial growth factor diabetic macular edema age-related macular degeneration endophthalmitis visual acuity

Mineralogy and geochemistry of fine-grained Dahab stream sediments, Southeastern Sinai, Egypt: emphasis on the intergrowths of Fe–Ti oxides

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Acta Geochimica 2021年第6期40卷 871-894页

作者： Adel A.Surour ahmed.M.A.El-Kammar Ebtisam h.Arafa hala M.Korany Petroleum and Mining Geology Faculty of SciencesGalala University43511 New Galala CityEgypt Department of Geology Faculty of ScienceCairo UniversityGiza 12613Egypt

Mineralogical and geochemical characteristics of stream sediments collected from 30 stations in the Dahab-Wadi Kid area(southeastern Sinai,Egypt)are *** studied sediments contain considerable amounts of heavy minerals,including abundant Fe–Ti oxides,with up to 25.94%index figure that measures the relative abundance of heavy minerals to light *** of the sediments and nature of Fe–Ti oxide intergrowths,in addition to some non-opaque heavy minerals,indicate multiple provenances with contributions from a variety of Neoproterozoic mafic to felsic *** amounts of heavy minerals are derived from schists that belong to the so-called Wadi Kid volcanosedimentary *** to the considerable contribution of the felsic intrusions represented by within-plate granites,the sediments are enriched in REE-bearing minerals(e.g.,monazite,cerianite,La-cerianite and allanite),V-bearing thorite,zircon,and a ZrO_(2) *** majority of Fe–Ti oxides are derived from the mafic intrusions,and they show evidence of pre-,syn-and post-depositional phases of alteration and formation of *** to the geochemical signature of the bulk silt fraction,there is remarkable enrichment of LREEs with distinct negative Eu anomaly,and this supports dominance of a provenance dominated by felsic intrusions(i.e.,the A-type within-plate granite and associated pegmatites).Also,the felsic provenance is responsible for slight abnormality of ∑PU+Th content(up to~37 ppm)and few anomalous samples bear uraniferous zircon and Ce-type *** present paper sheds light on the fertility of the Dahab stream sediments in some economic minerals for possible future exploitation,not for gold only,but for potential REEbearing minerals that are needed for a wide spectrum of modern technological industries.

关键词： Dahab stream sediments Silt fraction Fe-Ti oxides Textural variations Rees enrichment

Inducing opto-electronic and spintronic trends in bilayer h-BN through TMO3 clusters incorporation: Ab-initio study

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Chinese Physics B 2019年第11期28卷 284-294页

作者： Irfan ahmed Muhammad Rafique Mukhtiar ahmed Mahar Abdul Sattar Larik Mohsin Ali Tunio Yong Shuai Mehran University of Engineering and Technology SZABCampusKhairpur Mirs’Pakistan School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Mehran University of Engineering and Technology JamshoroSindhPakistan

The band structure, magnetism, charge distribution, and optics parameters of TMO3–h-BN hybrid systems are investigated by adopting first-principles study(FPS) calculations. It is observed that the TMO3 clusters add finite magnetic moments to bilayer h-BN(BL/h-BN), thereby making it a magnetic two-dimensional(2D) material. Spin-polarized band structures for various TMO3–BL/h-BN hybrid models are calculated. After the incorporation of TMO3, BL/h-BN is converted into semimetal or conducting material in spin up/down bands, depending on the type of impurity cluster present in BL/h-BN lattice. Optics parameters are also investigated for the TMO3–BL/h-BN complex systems. The incorporation of TMO3 clusters modifies the absorption and extinction coefficient in visible range, while static reflectivity and refraction parameter increase. It can be surmised that the TMO3 substitution in BL/h-BN is a suitable technique to modify its physical parameters thus making it functional for nano/opto-electronic applications, and an experimental approach can be adapted to reinforce the outcomes of this study.

关键词： bilayer h-BN band structure density of states magnetic moments optics