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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

Network Analysis for Projects with High Risk Levels in Uncertain Environments

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Computers, materials & Continua 2022年第1期70卷 1281-1296页

作者： mohamed Abdel-Basset Asmaa Atef mohamed Abouhawwash Yunyoung Nam Nabil m.AbdelAziz Faculty of Computers and Informatics Zagazig UniversityZagazig44519Egypt Department of mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Computational mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast Lansing48824MIUSA Department of Computer Science and Engineering Soonchunhyang UniversityAsan31538Korea

The critical path method is one of the oldest and most important techniques used for planning and scheduling *** main objective of project management science is to determine the critical path through a network representation of *** critical path through a network can be determined by many algorithms and is useful for managing,monitoring,and controlling the time and cost of an entire *** essential problem in this case is that activity durations are uncertain;time presents considerable uncertainty because the time of an activity is not always easily or accurately *** issue increases the need to use neutrosophic theory to solve the critical path ***-world problems are characterized by a lack of precision,consistency,and *** concept of neutrosophic sets has been introduced as a generalization of fuzzy,intuitionistic fuzzy,and crisp sets to overcome the ambiguity surrounding real-world ***-,falsity-,and indeterminacy-membership functions are used to express neutrosophic *** study was performed to examine a neutrosophic event-oriented algorithm for determining the critical path in activity-on-arc *** activity time estimates are presented as trapezoidal neutrosophic numbers,and score and accuracy functions are used to obtain a crisp model of the *** appropriate numerical example is then used to explain the proposed method.

关键词： Project management project life cycle project planning project scheduling CPm neutrosophic set theory trapezoidal neutrosophic number

Electron Acceleration by microwave Radiation Inside a Rectangular Waveguide

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Plasma Science and Technology 2011年第3期13卷 357-361页

作者： B. F. mohamed A.m. GOUDA Plasma Physics Department N.R.C. Atomic Energy Authority Cairo Egypt

Electron dynamics in the fields associated with a transverse magnetic （Tm） wave propagating inside a rectangular waveguide is analytically studied. The relativistic momentum and energy equations for an electron are solved, which was injected initially along the propagation direction of the microwave. Expressions of the acceleration gradient and deflection angle are obtained. In principle, it is shown that the electron can be accelerated in this condition and there is no deflection when the electron is injected from the centre of the waveguide front. However, it is found that the acceleration gradient and deflection angle depend strongly on the parameters of the microwave （intensity, frequency, etc.） and the dimensions of the waveguide.

关键词： waveguide electron acceleration polarized microwave

Geochemistry of lamprophyres associated with uranium mineralization, Southeastern Desert, Egypt

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Chinese Journal Of Geochemistry 2007年第4期26卷 356-365页

作者： mohamed E. Ibrahim mohamed m. El-Tokhi Gehad m. Saleh mamdouh A. Hassan mohamed A. Rashed Nuclear materials Authority P. O. Box 530 El Maadi Cairo Egypt Geology Deprtment Faculty of Science United Arab Emirates University United Arab Emirates

Two brecciated shear zones (NNW-SSE) are found crosscutting cataclastic rocks. The cataclastic rocks (3.0 km2) occupy the core of the granitic pluton and enclose a roof pendant of mafic-ultramafic rocks. The NNW-SSE-extending lamprophyre dykes vary in thickness from 0.5 m to 1 m and up to 800 m long, cutting the cataclastic rocks and are composed mainly of plagioclases, amphiboles, relics of pyroxenes and K-feldspar phenocrysts embedded in fine-grained groundmass. They are characterized as being peraluminous, calc-alkaline in composition (chemical trap) and enriched in calcite, sulfide and P2O5. The lamprophyres were affected by hydrothermal alteration (chlorite-carbonate alteration) while the cataclastic rocks were affected by diagenetic alteration (K-feldspar-albite alteration). Uranium mineralization is the product of hydrothermal events and has been investigated by X-ray diffraction (XRD) and environmental scanning electron microscopy (ESEm), involving primary uranium minerals (U3O8) and secondary uranium minerals (uranophane and beta-uranophane, kasolite, torbernite, autonite and meta-autonite) in addition to U- bearing minerals (astrocyanite, betafite and fergusonite). The presence of different mineral parageneses associated with clay minerals indicates that the lamprophyres were subjected to acidic and alkaline mineralizing solutions. moreover, the U-Zr/U, U-Ce/U values show negative correlations, confirming U-enrichment in both cataclastic rocks and shear zones while the Th-eU/eTh, Th-Zr/Th and Th-Ce/Th values show negative correlations, indicating that the U-bearing solutions are rich in Th in the cataclastic rocks only.

关键词：碎裂岩石剪切区域煌斑岩热液蚀变埃及西南地区沙漠地带

A new technique for fault diagnosis in transformer insulating oil based on infrared spectroscopy measurements

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High Voltage 2024年第2期9卷 319-335页

作者： mohamed m.F.Darwish mohamed H.A.Hassan Nagat m.K.Abdel-Gawad matti Lehtonen Diaa-Eldin A.mansour Department of Electrical Engineering Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of Electrical Engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland Department of Electrical Power Engineering Egypt-Japan University of Science and Technology(E-JUST)New Borg El-Arab CityEgypt Department of Electrical Power and machines Engineering Faculty of EngineeringTanta UniversityTantaEgypt

Condition monitoring of the insulating system within power transformers has a massive importance according to the electrical *** gas analysis(DGA)is frequently used for this ***,DGA lacks the necessary level of accuracy to identify all equipment faults,particularly in their initial stages of ***,it does not have the capability for real-time monitoring and relies on manual sampling and laboratory testing,causing potential delays in fault ***,the interpretation of DGA data necessitates specialised expertise,which may pose difficulties for smaller entities that have limited access to ***,the contribution of this research is to use infrared spectroscopy measurements as a new effective technique substituting the DGA method for fault diagnosis in insulating *** inception faults that were considered in this study were the electrical fault(discharges of high energy)and the thermal fault(300°Cmperaturemulation processes inside the laboratory for both types of inception ***,six samples of pure paraffinic mineral oil were taken to be degraded in the *** that,all of them besides another sample that were not subjected to any kind of faults were taken to be examined by Fourier transform infrared(FTIR)spectroscopy to obtain an overview of the oil's behaviour in each fault *** that,the FTIR analysis was initially verified utilising the DGA ***,for further affirmation,the dielectric dissipation factor(DDF)for all samples was *** the final analysis,the verification tests provide experimental evidence about the outperformance of this new optical technique in detecting the transformer's inception faults in addition to proving its potential for being a superior alternative to the well-known traditional diagnostic techniques.

关键词： fault diagnosis spectroscopy

macrobenthos monitoring in the Gulf of Suez,Egypt

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Acta Oceanologica Sinica 2008年第2期27卷 55-80页

作者： mohamed m.El-Komi National Institute of Oceanography and Fisheries

The biogeography of macrobenthic communities with large-scale differences in species distribution and abundance was studied along the eastern and western coastal regions of the Gulf of Suez to indicate biodiversity of benthos in relation to the prevailing environmental conditions. In general, benthos have a wide variety of species of mainly polychaet worms, crustaceans, bivalves, and other bottom invertebrates living in burrows in/or on the sediment surface. Coastal development clearly affects the ecosystem after the construction of coastal projects. The highest values of benthic diversity, evenness, richness and dominance are found at the Gulf of Suez （WG 1, WG 3）, Ras Gharib （WG 7, WG 8） and Ras Shukier （WG 9a） by contrast to others. The abundance of macrobenthic organsims along the coasts of Gulf of Suez can be arranged in the following sequence： other groups （34%） greater than crustaceans （25%） greater than polychaetes （22%） greater than molluscs （17%） greater than echinoderms （2%）. The biomass of benthic assemblages at different sampling sites can also be ranked as follows： echinoderms （52%） greater than molluscs （27%） greater than crustaceans （16%） greater than polychaetes （2%） greater than other groups （3%）. Some benthic groups or species indicated a distinctive correlation to pollution sources in the marine ecosystem which obviously increased in the coastal areas due to the extension of the coastal development. These activities needed regular information to establish database for the biology and distribution of marine benthic communities. The density and diversity of benthos are significantly affected by eutrophication at Ain Sukhna, whereas the benthos in the open Gulf of Suez do not seem to be adversely affected by pollution.

关键词： macrobenthos assessment impact Gulf of Suez

Citrus reticulata Blanco (the common mandarin) fruit:An updated review of its bioactive,extraction types,food quality,therapeutic merits,and bio-waste valorization practices to maximize its economic value

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Food Bioscience 2022年第3期47卷 67-80页

作者： mohamed Shorbagi Nesrin m.Fayek Ping Shao mohamed A.Farag Department of Special Chemistry Faculty of ScienceBenha UniversityAl Qalyubia GovernorateEgypt Pharmacognosy Department College of PharmacyCairo UniversityKasr El Aini st.11562CairoEgypt College of Food Science and Technology Zhejiang University of TechnologyZhejiangHangzhou310014PR China

Fruits are regarded as the richest dietary sources of polyphenols,carotenoids,terpenoids,and limonoids,making them highly desired prospects for the functional food *** waste that remains after fruit processing is also regarded as a valuable source of value-added phytochemicals.A comprehensive analysis of mandarin composition as a determinant of fruit functional properties,health benefits,and valorization into useful products is represented together with the effect of different processes such as light,wax coating,auxin addition,ozone treatment,and ethylene *** reviewing evidence is an essential precondition for improving the selling market of mandarin and highlighting its waste valorization potential and its incorporation into useful products produced by pharmaceutical *** this study,the phytochemical and biological reports presented to emphasize the needed priority for agricultural techniques to provide a certain mandarin product or *** addition,the paper summarizes the optimum conditions applied for the updated extraction techniques for phenolic acids,flavonoids,and oils at a commercial scale from mandarin peels and to enhance its global marketing.A brief representation is given towards potential mandarin patents and the valorization of its bio-waste fruits into commercial products of added *** review can guide researchers to produce future potentially marketed functional food enriched with mandarin extracts and/or bioactives.

关键词： Citrus reticulata Phytochemical composition Biological effects Waste valorization Extraction techniques Processing effect

An adaptive neuro-fuzzy sliding mode controller for mImO systems with disturbance

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Chinese Journal of Chemical Engineering 2017年第4期25卷 463-476页

作者： mahmoud m.Saafan mohamed m.Abdelsalam mohamed S.Elksas Sabry F.Saraya Fayez F.G.Areed Computers and Control Systems Engineering Department Faculty of EngineeringMansoura UniversityEgypt

This paper introduces the mathematical model of ammonia and urea reactors and suggested three methods for designing a special purpose controller. The first proposed method is Adaptive model predictive controller, the second is Adaptive Neural Network model Predictive Control, and the third is Adaptive neuro-fuzzy sliding mode controller. These methods are applied to a multivariable nonlinear system as an ammonia–urea reactor system. The main target of these controllers is to achieve stabilization of the outlet concentration of ammonia and urea, a stable reaction rate, an increase in the conversion of carbon monoxide(CO) into carbon dioxide(CO_2) to reduce the pollution effect, and an increase in the ammonia and urea productions, keeping the NH_3/CO_2 ratio equal to 3 to reduce the unreacted CO_2 and NH_3, and the two reactors' temperature in the suitable operating ranges due to the change in reactor parameters or external disturbance. Simulation results of the three controllers are compared. Comparative analysis proves the effectiveness of the suggested Adaptive neurofuzzy sliding mode controller than the two other controllers according to external disturbance and the change of parameters. moreover, the suggested methods when compared with other controllers in the literature show great success in overcoming the external disturbance and the change of parameters.

关键词： disturbance sliding ammonia stabilization outlet predictive monoxide dioxide overcome steam

Fabrication,characterization,and electrical conductivity properties of Pr_6O_(11) nanoparticles

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Journal of Rare Earths 2013年第7期31卷 701-708页

作者： Bahaa m.Abu-Zied Youssef A.mohamed Abdullah m.Asiri Chemistry Department Faculty of ScienceKing Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia Chemistry Department Faculty of ScienceAssiut University71516 AssiutEgypt Center of Excellence for Advanced materials Research(CEAmR) King Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia

PrrOll nanoparticles were obtained by subsequent thermal decomposition of the as-prepared precipitate formed under ambient temperature and pressure using NaOH as precipitant. The calcination process was affected, for 1 h in static air atmosphere, at 400-700 ℃ temperature range. The different samples were characterized using X-ray diffraction （XRD）, transmission electron microscopy （TEm）, field emission scanning electron microscopy （FE-SEm）, thermogravimetric analysis （TGA）, in situ electrical conductivity, and N2 adsorption/desorption. The obtained results demonstrated that nano-crystalline Pr6O11, with crystallites size of 6-12 nm, started to form at 500 ℃. Such value increased to 20-33 nm for the sample calcined at 700℃. The as-synthesized PrrOll nanoparticles presented high electrical conductivity due to electron hopping between Pr（III）-Pr（IV） pairs.

关键词： nanocrystalline praseodymium oxide Pr6O11 nano structured materials electrical conductivity rare earths

A robust multi-objective and multi-physics optimization of multi-physics behavior of microstructure

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Journal of Central South University 2016年第12期23卷 3225-3238页

作者： Hamda Chagraoui mohamed Soula mohamed Guedri Research Unit in Structural Dynamics Modeling and Engineering of Multi-Physics SystemsSDMESMNabeul Preparatory Engineering Institute-IPEINUniversity of Carthage Laboratory of Applied mechanics and Engineering ENITDepartment of Mechanical engineering ENSITTunis University of Tunisia

A new strategy is presented to solve robust multi-physics multi-objective optimization problem known as improved multi-objective collaborative optimization （ImOCO） and its extension improved multi-objective robust collaborative （ImORCO）. In this work, the proposed ImORCO approach combined the ImOCO method, the worst possible point （WPP） constraint cuts and the Genetic algorithm NSGA-II type as an optimizer in order to solve the robust optimization problem of multi-physics of microstructures with uncertainties. The optimization problem is hierarchically decomposed into two levels： a microstructure level, and a disciplines levels, For validation purposes, two examples were selected： a numerical example, and an engineering example of capacitive micro machined ultrasonic transducers （CmUT） type. The obtained results are compared with those obtained from robust non-distributed and distributed optimization approach, non-distributed multi-objective robust optimization （NDmORO） and multi-objective collaborative robust optimization （mcRO）, respectively. Results obtained from the application of the ImOCO approach to an optimization problem of a CmUT cell have reduced the CPU time by 44% ensuring a Pareto front close to the reference non-distributed multi-objective optimization （NDmO） approach （mahalanobis distance, D2m =0.9503 and overall spread, So=0.2309）. In addition, the consideration of robustness in ImORCO approach applied to a CmUT cell of optimization problem under interval uncertainty has reduced the CPU time by 23% keeping a robust Pareto front overlaps with that obtained by the robust NDmORO approach （D2m =10.3869 and So=0.0537）.

关键词： multi-physics multi-objective optimization robust optimization collaborative optimization non-distributed anddistributed optimization uncertainty interval