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Nuclear Science and Techniques 2022年第2期33卷 1-13页

作者： khaled M.el-Azony Nader M.A.mohamed dalal A.Aloraini Radioactive Isotopes and Generators department Hot Labs.CenterEgyptian Atomic Energy AuthorityP.O.Box 13759CairoEgypt Reactors department Egyptian Atomic Energy AuthorityP.O.Box 13759CairoEgypt Physics department College of SciencePrincess Nourah Bint Abdulrahman UniversityRiyadhKingdom of Saudi Arabia

Production routes were recorded on available reactions for^(111)Ag production from nuclear reactors or cyclotrons using a natural palladium target based on^(110)Pd(n,γ)and^(110)pd(d,n)reactions,respectively.^(nat)Cd(γ,x)based on^(110)Cd(γ,p)has also been studied as a prospective reaction for the production of^(111)***,these nuclear reactions are difficult to utilize because,in some cases,they reduce the specific activity of^(111)*** is a consequence of the stable silver isotopes produced in high *** isotopes include^(107,109)Ag and,in other cases,the high impurity of silver radioisotopes,such as^(110)m,^(106)m,^(105)Ag,that are produced during parallel nuclear *** to a scarcity of data regarding the(γ,α)reaction,the gamma reaction on natural indium for^(111)Ag production based on the^(115)In(γ,α)reaction was *** ^(nat)In(γ,α)reaction satisfies the criteria as a possible reaction to produce^(111)Ag with a sufficient yield and purity as consequence of the high^(115)In(95.7%)abundance as an enriched form and a relatively soft background caused by the parallel nuclear reactions.

关键词： Silver-111 Nuclear data Natural cadmium Natural palladium Natural indium

Multiple sclerosis: New insights and trends

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Asian Pacific Journal of Tropical Biomedicine 2016年第5期6卷 429-440页

作者： khaled mohamed mohamed Koriem department of Medical Physiology Medical Research DivisionNational Research Centre

Multiple sclerosis(MS) is the most famous autoimmune disease attacking the central nervous system. It attacks people from age 20–50 years old and the females' attacks double than males' attacks. MS is an autoimmune disease affecting principally the central nervous system that cause nerve sheath demyelination followed by axon damage and paralysis. MS symptoms include muscle weakness, weak reflexes, muscle spasm, difficult in move, miss-coordination and unbalance with others. There are many factors may be responsible for MS: microbial, viral, smoking, stress, environmental toxins, contaminated diet, and gout. MS is wide spread in the populations in North Europe and this related to lack of vitamin d due to decrease of sunlight exposure. MS biomarkers include nitric oxide, interleukin-6, nitric oxide synthase, fetuin-A and osteopontin. MS is not a genetic disease where MS occurs when human leukocyte antigen system related genes are changed in chromosome 6. The physiology of MS is monitored by activation of immuneinflammatory, oxidative, and nitrosative stress pathways. MS is including two main steps:(1) myelin sheath destruction and formation of lesions and,(2) inflammation. Four types of MS can be distinguished: relapsing-remitting, primary progressive, secondary progressive and progressive relapsing. Nine treatments have been accepted for relapsingremitting MS type: interferon b-1a, interferon b-1b, mitoxantrone, natalizumab, glatiramer acetate, fingolimod, dimethyl fumarate, teriflunomide, and alemtuzumab, however,the only treatment used is mitoxantrone for progressive MS but many of MS treatments side effects are recorded. Complementary treatments also used in MS treatments such as:vitamin d, Yoga, medicinal plants, oxygen therapy, acupuncture and reflexology.

关键词： Multiple sclerosis diagnosis Genetics Physiology Treatments

Loading characteristics of mechanical rib bolts determined through testing and numerical modeling

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International Journal of Mining Science and Technology 2020年第1期30卷 17-24页

作者： khaled mohamed Gamal Rashed Zorica Radakovic-Guzina Centers for disease Control National Institute for Occupational Safety and HealthPittsburghPA 15236USA ITASCA Consulting Group MinneapolisMN 55401USA

Underground coal mines use mechanical bolts in addition to other types of bolts to control the rib deformation and to stabilize the yielded coal *** research has been conducted to understand the performance of the mechanical bolts in coal *** from the National Institute for Occupational Safety and Health(NIOSH)conducted this work to understand the loading characteristics of mechanical bolts(stiffness and capacity)installed in coal ribs at five underground coal *** pull-out tests were performed in this study to define the loading characteristics of mechanical rib *** installation torques were applied to the tested bolts based on the strength of the coal seam.A typical tri-linear load-deformation response for mechanical bolts was obtained from these *** was found that the anchorage capacity depended mainly on the coal *** for modeling mechanical bolts have been developed using the tri-linear load-deformation *** outcome of this research provides essential data for rib support design.

关键词： Coal rib Mechanical bolt Conventional bolt Tension bolt Point-anchored bolt Rib support Pull-out test Numerical modeling FLAC3d

Effect of Si-addition as a grain refiner on microstructure and properties of Ti-6Al-4V Alloy

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Transactions of Nonferrous Metals Society of China 2013年第7期23卷 1863-1874页

作者： khaled M.IBRAHIM Abdel Hamied HUSSEIN mohamed ABdelKAWY Central Metallurgical R&d Institute CMRDICairoEgypt Cairo University GizaEgypt

Two different Ti alloys were cast in a graphite mould using vacuum induction skull melting furnace. The first alloy was Ti-6Al-4V and the second was Ti-6Al-4V 0.5Si. Silicon as a grain refiner was added into Ti-6Al-4V alloy, and the effects of Si-addition on the microstructure and properties of the as-cast and swaged alloys were investigated. Hot swaging at 900 °C was performed on the cast samples and then two different thermal treatments were applied. The first treatment was done by heating the swaged samples at 1050 °C to produce fine lamella structure, while the second treatment was carried out at 1050 °C and then decreased the temperature to 800 °C for getting coarse lamella structure. An addition of 0.5% Si to Ti-6Al-4V alloy decreased the grain size of the as-cast sample from 627 to 337 μm. There was an increase in ultimate tensile strength of about 25 MPa for the as-cast Ti-6Al-4V 0.5Si alloy compared to Ti-6Al-4V due to the refinement effect caused by Si addition. A maximum ultimate tensile strength of 1380 MPa and a minimum corrosion rate （1.35×10 6 mm/a in Hank’s solution and 5.78×10 4 mm/a in NaCl solution） were reported for the heat treated fine lamella structure of Ti-6Al-4V 0.5Si alloy. The wear rate was decreased to about 50% by adding 0.5% Si at low sliding speeds and to about 73% at high sliding speeds.

关键词： Ti-6Al-4V alloy silicon casting grain refinement heat treatment wear

Investigation of the volatile oils,lipid constituents and biological activity of Ballota andreuzziana,Teucrium zanonii and Verbena tenuisecta in Libya

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Asian Pacific Journal of Tropical Medicine 2010年第8期3卷 594-601页

作者： khaled A Abdelshafeek Adnan A elgattar Aziza H Zarkoon mohamed A Alwahash Abdelaaty A Shahat Al-Tahady University Faculty of ScienceChemistry DepartmentPO 674SirtLibya Phytochemistry department National Research Centre12311 DokkiCairoEgypt Sebha University Faculty of Science Chemistry DeptartmentSebhaLibya

Objective:To determine the chemical composition of essential oils and lipid constituents of Ballola andreuzziana(***),Teucrium zanonii(***) and Verbena tenuisecta(V. tenuisecta) growing in Libya,and to test the antibacterial activity of different extracts of Teucrium ***:The volatile oils of all plants were extracted by hydrodistillation method and analyzed by GC/MS *** lipid constituents of plants were obtained by extraction with petroleum ether and fractionated into fatty alcohols,fatty acids and unsapoinfiable matters. Antibacterial activity of *** extracts and antioxidant activity of different extracts of T. zanonii were also ***:The volate oil of *** was found to consists of 20 compounds in which caryophyllin is the main one(63.1%),the volatile oil of *** consists of 74 compounds in which germacrene-d was the main compound,while the volatile oil of V. tenuisecta consists of 13 compounds with l-octen-3- ol as a major constituent(52.87%).The study of antimicrobial activity of different extracts of *** showed that,both methanol and butanol extracts exhibited the highest activity against Mycobacterium phlei(***) and Candida albicans(***) respectively,while petroleum ether,fatty alcohols and unsaponifiable fractions had no antimicrobial activity against all the tested microorganisms. Investigation of the antioxidant activity of different extracts of *** using dPPH method proved that,the ethyl acetate and butanol fractions showed the highest activity where the inhibition percentage(1%) are 93.6 and 92.1 ***:This is the first report about the volatile oils of these plants where *** have the highest content and the highest number of the identified *** study of antioxidant *** extracts proved that,the ethyl acetate,butanol and aqueous extracts have the highest antioxidant *** and butanol extracts of *** exhibi

关键词： Ballota andreuzziana Teucrium zanonii Verbena tenuisecta Volatile oil Lipid constituents Biological activity

Multiphysics simulation of VVER-1200 fuel performance during normal operating conditions

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Nuclear Science and Techniques 2023年第2期34卷 139-152页

作者： khaled M.Yassin mohamed H.Hassan Mohammad M.Ghoneim Mostafa S.elkolil Adel Alyan Said A.Agamy Nuclear Research Center Egyptian Atomic Energy AuthorityAbo Zaabal 13759CairoEgypt department of Nuclear and Radiological Engineering Faculty of EngineeringAlexandria UniversityAlexandria 21544Egypt Faculty of Engineering Egyptian Russian UniversityBadr 11829Egypt

Nuclear fuel performance modeling and simulation are critical tasks for nuclear fuel design optimization and safety analysis under normal and transient *** performance is a complicated phenomenon that involves thermal,mechanical,and irradiation mechanisms and requires special multiphysics *** this study,a fuel performance model was developed using the COMSOL Multiphysics *** modeling was performed for a 2d axis-symmetric geometry of a UO2fuel pellet in the E110 clad for VVER-1200 *** modeling considers all relevant phenomena,including heat generation and conduction,gap heat transfer,elastic strain,mechanical contact,thermal expansion,grain growth,densification,fission gas generation and release,fission product swelling,gap/plenum pressure,and cladding thermal and irradiation *** model was validated using a code-to-code evaluation of the fuel pellet centerline and surface temperatures in the case of constant power,in addition to validation of fission gas release(FGR)*** prediction proved that the model could perform according to previously published VVER nuclear fuel performance parameters.A sensitivity study was also conducted to assess the effects of uncertainty on some of the model *** model was then used to predict the VVER-1200 fuel performance parameters as a function of burnup,including the temperature profiles,gap width,fission gas release,and plenum pressure.A compilation of related material and thermomechanical models was conducted and included in the modeling to allow the user to investigate different material/performance *** the model was developed for normal operating conditions,it can be modified to include off-normal operating conditions.

关键词： VVER-1200 Fuel performance COMSOL code Zr-1%Nb cladding UO2 fuel rod

Effect of Transcranial direct Current Stimulation of Motor Cortex versus Insula Cortex on Chronic Post-Mastectomy Pain: Randomized Sham-Controlled Trial

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Open Journal of Anesthesiology 2023年第10期13卷 197-211页

作者： Shereen Mamdouh Kamal khaled mohamed Fares Sahar Abdel-Baky mohamed Mohanad Ahmed mohamed Fatma Adel el Sherif Anaesthesia Intensive Care and Pain Management Department South Egypt Cancer Institute Assiut University Assiut Egypt

Background: Transcranial direct current stimulation (tdCS) across cortical brain areas appears to improve various forms of pain, yet evidence of tdCS efficiency and ideal stimulation target is lacking. This study aimed to compare the add-on analgesic efficacy of concentric electrode transcranial direct current stimulation (CE-tdCS) stimulation over the primary motor cortex versus the insular cortex on the management of chronic postmastectomy pain. Method: Prospective randomized double-blind sham-controlled study enrolled eighty patients with chronic postmastectomy pain that were randomly assigned to four groups: active motor (AM), sham motor (SM), active insula (AI) and sham insula (SI) group, each received 5 sessions for 20-minute duration with 2 mA tdCS over the targeted area of the contralateral side of pain. Our primary outcome was VAS score, the secondary outcomes were VdS score, LANSS score and depression symptoms by HAM-d scores, assessment was done at 4 time points (prestimulation, after 5th session, 15th day and one month after the last session). Results: Both active tdCS groups (motor and insula) showed reduction of VAS (P Conclusion: Active tdCS stimulation either targeting the primary motor cortex or the insula cortex has add-on analgesic effect for controlling neuropathic chronic post mastectomy pain and the maximum effect was at 15 days after the last session.

关键词： Transcranial direct Current Stimulation tdCS Postmastectomy Pain Motor Cortex Insular Cortex

Influence of Recycling Waste Glass as Fine Aggregate on the Concrete Properties

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Journal of Renewable Materials 2023年第6期11卷 2925-2940页

作者： Rafal A.Hadi Suhad M.Abd Hadee Mohammed Najm Shaker Qaidi Moutaz Mustafa A.eldirderi khaled mohamed Khedher department of Civil Engineering Bilad Alrafidain University CollegeDiyala32001Iraq department of Civil Engineering College of EngineeringUniversity of DiyalaDiyala32001Iraq department of Civil Engineering Zakir Husain Engineering CollegeAligarh Muslim UniversityAligarh202002India department of Civil Engineering College of EngineeringUniversity of DuhokDuhok42001Iraq department of Civil Engineering College of EngineeringNawroz UniversityDuhok42001Iraq department of Chemical Engineering College of EngineeringKing Khalid UniversityAbha61421Saudi Arabia department of Civil Engineering College of EngineeringKing Khalid UniversityAbha61421Saudi Arabia department of Civil Engineering High Institute of Technological StudiesMrezgua University CampusNabeul8000Tunisia

Recent years have witnessed an increase in the quantity of waste glass(WG)across the *** the fine aggregate with WG is one of the steps toward preserving the natural resources of the environment and creating low-cost *** present study is concerned with replacing fine aggregates with glass powder(GP)at(0%,15%,30%,and 50%).It has studied the fresh and hardened properties(compressive strength,tensile strength,hardened density,and slump)for all the mentioned percent *** findings have shown that all mixtures containing GP gave acceptable slump results within the design limits(2–5 cm)according to ACI standard *** has been observed that increasing the proportion of GP led to a decrease in the weight of ***,replacing GP with sand by 30%has led to an increase in the compressive strength by about 2.4%and 12.45%,and the tensile strength by about 2.5%and 26.54%at 7-and 28-d,respectively in comparison to normal concrete.

关键词： Sustainable concrete glass powder fine aggregate partial replacement

A Speech Cryptosystem Using the New Chaotic System with a Capsule-Shaped Equilibrium Curve

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Computers, Materials & Continua 2023年第6期75卷 5987-6006页

作者： Mohamad Afendee mohamed Talal Bonny Aceng Sambas Sundarapandian Vaidyanathan Wafaa Al Nassan Sen Zhang khaled Obaideen Mustafa Mamat Mohd Kamal Mohd Nawawi Faculty of Informatics and Computing Universiti Sultan Zainal AbidinMalaysia department of Computer Engineering University of SharjahSharjah26666UAE department of Mechanical Engineering Universitas Muhammadiyah TasikmalayaIndonesia Research and development Centre Vel Tech UniversityAvadiChennaiIndia School of Artificial Intelligence and Automationand Key Laboratory of Image Processingand Intelligent Control of Education Ministry of ChinaHuazhong University of Scienceand TechnologyWuhan430074China Institute of Strategic Industrial decision Modeling School of Quantitative SciencesUniversiti Utara Malaysia06010UUM SintokKedahMalaysia

In recent years,there are numerous studies on chaotic systems with special equilibrium curves having various shapes such as circle,butterfly,heart and *** paper describes a new 3-d chaotic dynamical system with a capsule-shaped equilibrium *** proposed chaotic system has two quadratic,two cubic and two quartic nonlinear *** is noted that the proposed chaotic system has a hidden attractor since it has an infinite number of equilibrium *** is also established that the proposed chaotic system exhibits multi-stability with two coexisting chaotic attractors for the same parameter values but differential initial states.A detailed bifurcation analysis with respect to variations in the system parameters is portrayed for the new chaotic system with capsule equilibrium *** have shown MATLAB plots to illustrate the capsule equilibrium curve,phase orbits of the new chaotic system,bifurcation diagrams and *** an engineering application,we have proposed a speech cryptosystem with a numerical algorithm,which is based on our novel 3-d chaotic system with a capsule-shaped equilibrium *** proposed speech cryptosystem follows its security evolution and implementation on Field Programmable Gate Array(FPGA)*** results show that the proposed encryption system utilizes 33%of the FPGA,while the maximum clock frequency is 178.28 MHz.

关键词： Chaos chaotic systems hidden attractors multi-stability bifurcation speech cryptosystem FPGA design

Geophysical Investigation of the Triassic Salt Material Hazard: el Fahs Case Example (Northern Tunisia)

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International Journal of Geosciences 2020年第11期11卷 729-744页

作者： mohamed khaled Bouzid Adel Klai Romdhane Haddad mohamed Chedly Rabia Faculty of Sciences of Bizerte University of Carthage Tunis Tunisia Research Laboratory “Geomatics of Geosystems” LR19ES07 Faculty of Letters Arts and Humanities of Mannouba Mannouba University Manouba Tunisia

The Tunisian territory (area of diapirs) is exposed to the risks of ground movements linked to water, some of which are related to the phenomenon of dissolution of gypsum, allowing the appearance of underground cavities which present natural risks and set people in danger. The analysis of the hazard was determined by the field study coupled with the application of geophysical methods to locate and map the cavities and identify their dimensions and their positions in the subsoil. In the region of el Fahs (40 km NW of Tunis): we used a non-destructive method, georadar (GPR) with a 200 MHz antenna band-width, and an electric method, by using the electric tomography of which we have applicated the sequence of dipole-dipole measurement. The results ob-tained were examined and interpreted according to 2d profiles. The geophysi-cal methods of GPR and electrical tomography aim to detect many calvities in different depths. However, the geological radar was able to identify several cavities and the zones of dissolution whose investigation depth did not exceed the first 3 meters. On the contrary, the electric tomography method allowing the presence of several deeper underground cavities with larger dimensions ex-tended to 64 meters. To conclude, the geological and hydrogeological contexts of the terrain studied and on the state of the soil and subsoil allow us to better understanding the mechanisms of the establishment of the dissolution phe-nomenon and the appearance of cavities in the basement. The analysis of the predisposing factors present in the study area shows that the geodynamic con-text of the Triassic ascent takes place according to a precise thermodynamic process that favors the phenomenon of dissolution of the gypsum.

关键词： Triassic Materials Natural Hazards Underground Cavities Thermodynamic Process GPR electric Tomography