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Pack Aluminizing of Copper

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Journal of materials Science & Technology 1997年第2期13卷 127-132页

作者： m.E.Abd El-Azim h.m.soliman (metallurgy Dept., Atomic Energy Authority Cairo, Egypt) metallurgy Dept. Atomic Energy Authority Cairo Egypt

Aluminizing of Cu by a pack cementation process was performed to improve its surface *** effect of variation of pack aluminizing temperature from 800 to 900℃ and aluminizing time from 1 to 6 h on the microstructure and the thickness of the aluminide coating of Cu was investigated. Pack aluminizing of Cu significantly improved the microhardness and the oxidation resistance. The microhardness was increased about seven times and the oxidation resistance,after 96 h exposure in air at 900℃, was extremely increased ten times by aluminizing Cu at 900℃ for 3 h.

关键词： VhN Pack Aluminizing of Copper

Performance of the Aluminide Coating of SomeLow Alloy Steels

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Journal of materials Science & Technology 1997年第6期13卷 462-466页

作者： h.m.soliman and m.E.Abd E1-Azim(metallurgy Dept., Atomic Energy Authority, Cairo, Egypt ) metallurgy Dept. Atomic Energy Authority Cairo Egypt

Two low alloy steels 0.5Cr-0.5mo-0.25V and h85 were pack-aluminized at 900°for 4 h by using fe-Al powder mixture containing 48% fe, 20.6% Al- 29.4% Al2O3 and 2% Nh4Cl by weight. The microhardness and oxidation resistance at 900℃ of the aluminide coatings were studied. It was found that pack-aluminizing improves the microhardness of the 0.5Cro.5mo-0.25V steel while it reduces the microhardness of the h85 steel. Pack aluminizing highly improves the oxidation resistance after 20h exposure at 900℃ in air for the investigated steels.

关键词： Cr Performance of the Aluminide Coating of SomeLow Alloy Steels

Oxidation Resistance of the Aluminide Coating formed on Carbon Steels

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Journal of materials Science & Technology 1997年第5期13卷 383-388页

作者： soliman, h.m. mohamed, K.E. Abd El-Azim, m.E. hammad, f.h. metallurgy Dept. Atomic Energy Authority Cairo Egypt

Low and medium carbon steels were aluminized by the pack aluminizing technique using halideactivated pure-Al and fe-Al packs. The effect of mixture composition, aluminizing temperatureand time and C content of the steel substrate on the structure and thickness of the aluminidelayer, and on the oxidation resistance was investigated. The optimum oxidation resistance canbe achieved with a low carbon steel substrate when the intermetallic phases fe3Al and feAlform the surface of the aluminide layer. In this case, the Al concentration at the surface of thealuminide coating is at least ≥15 wt pct. formation of high Al concentration phases (feAl3 andfe2Al5) during aluminizing should be avoided as they tend to embrittle the aluminide layer andreduce its oxidation resistance.

关键词： OO figure Oxidation Resistance of the Aluminide Coating formed on Carbon Steels

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4 kJ Plasma focus

中国核科技报告 1999年第S4期 374-375页

作者： h.m.soliman,G.m.Elkashef Plasma Physics and Nuclear fusion Department Nuclear Research Center Atomic Energy Authority Cairo Egypt Plasma Physics and Nuclear fusion Department Nuclear Research Center Atomic Energy Authority Cairo Egypt

The work described in this paper is a combination of plasma focus electrical parameters and plasma sheath axial phase dynamics. 4 kJ plasma focus device of mather type, is powered by two modules capacitor bank of 61.68 μf capacity, has been constructed for this course of study. The discharge takes place in helium gas with an operating pressure ranging from 0.5 to 1.5 Torr (1 Torr=133.3224 Pa). The experiments are conducted with charging voltages changes from 8 to 12 kV.

关键词： kJ Plasma focus

Optical and electrical characterizations of nanoparticle Cu_2S thin films

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Chinese Physics B 2014年第4期23卷 476-481页

作者： m.Saadeldin h.S.soliman h.A.m.Ali K.Sawaby Physics Department Faculty of Science Cairo University Physics Department Faculty of Education Ain-Shams University

Copper sulfide thin films are deposited onto different substrates at room temperature using the thermal evaporation technique. X-ray diffraction spectra show that the film has an orthorhombicchalcocite （7-Cu2S） phase. The atomic force microscopy images indicate that the film exhibits nanoparticles with an average size of nearly 44 nm. Specrtophotometric measurements for the transmittance and reflectance are carried out at normal incidence in a spectral wavelength range of 450 nm-2500 nm. The refractive index, n, as well as the absorption index, k is calculated. Some dispersion parameters are determined. The analyses of el and e2 reveal several absorption peaks. The analysis of the spectral behavior of the absorption coefficient, c~, in the absorption region reveals direct and indirect allowed transitions. The dark electrical resistivity is studied as a function of film thickness and temperature. Tellier＇s model is adopted for determining the mean free path and bulk resistance.

关键词： physical properties of Cu2S thermal evaporation nanoparticle Cu2S thin films

Influence of thyroid volume reduction on absorbed dose in ^(131)I therapy studied by using Geant4 monte Carlo simulation

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Chinese Physics C 2014年第5期38卷 62-68页

作者： Ziaur Rahman Sikander m mirza waheed Arshed Nasir m mirza waheed Ahmed health Physics Division Pakistan Institute of Nuclear Science and Technology Department of Physics and Applied mathematics Pakistan Institute of Engineering and Applied Sciences

A simulation study has been performed to quantify the effect of volume reduction on the thyroid absorbed dose per decay and to investigate the variation of energy deposition per decay due to β- and γ-activity of 131I with volume/mass of thyroid, for water, ICRP- and ICRU-soft tissue taken as thyroid material. A monte Carlo model of the thyroid, in the Geant4 radiation transport simulation toolkit was constructed to compute the β- and γ-absorbed dose in the simulated thyroid phantom for various values of its volume. The effect of the size and shape of the thyroid on energy deposition per decay has also been studied by using spherical, ellipsoidal and cylindrical models for the thyroid and varying its volume in 1-25 cm3 range. The relative differences of Geant4 results for different models with each other and mCNP results lie well below 1.870%. The maximum relative difference among the Geant4 estimated results for water with ICRP and ICRU soft tissues is not more than 0.225%. S-values for ellipsoidal, spherical and cylindrical thyroid models were estimated and the relative difference with published results lies within 3.095%. The absorbed fraction values for beta particles show a good agreement with published values within 2.105% deviation. The Geant4 based simulation results of absorbed fractions for gammas again show a good agreement with the corresponding mCNP and EGS4 results （±6.667%） but have 29.032% higher values than that of mIRD calculated values. Consistent with previous studies, the reduction of the thyroid volume is found to have a substantial effect on the absorbed dose. Geant4 simulations confirm dose dependence on the volume/mass of thyroid in agreement with mCNP and EGS4 computed values but are substantially different from mIRD8 data. Therefore, inclusion of size/mass dependence is indicated for 131I radiotherapy of the thyroid.

关键词： mean absorbed dose rate Geant4 monte Carlo simulation and 131I therapy

Nitriles in heterocyclic synthesis: studies on ethyl 3-amino-4,4-dicyano-3-butenoate

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Chinese Journal of Chemistry 1991年第5期9卷 461-466页

作者： soliman A.Y BAKEER h.m Department of Chemistry faculty of Education fayoum Cairo University Egypt Department of Chemistry Faculty of Education Fayoum Cairo University Egypt

New polyfunctionally substituted heterocyclic compounds were synthesized from ethyl 3-amino-4, 4-dicyano-3-butenoate (1) as a starting material.

关键词： CI studies on ethyl 3-amino-4,4-dicyano-3-butenoate Nitriles in heterocyclic synthesis

Continuous query scheduler based on operators clustering

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Journal of Central South University 2011年第3期18卷 782-790页

作者： m.Sami soliman 谭冠政 School of Information Science and Engineering Central South University

Data stream management system (DSmS) provides convenient solutions to the problem of processing continuous queries on data *** approaches for scheduling these queries and their operators assume that each operator runs in separate thread or all operators combine in one query plan and run in a single *** approaches suffer from severe drawbacks concerning the thread overhead and the stalls due to expensive *** overcome these drawbacks,a novel approach called clustered operators scheduling (COS) is proposed that adaptively clusters operators of the query plan into a number of groups based on their selectivity and computing cost using S-mean *** evaluation is provided to demonstrate the potential benefits of COS scheduling over the other scheduling *** can provide adaptive,flexible,reliable,scalable and robust design for continuous query processor.

关键词： data stream management systems operators scheduling continuous query clustering

E-mail Spam Classification Using Grasshopper Optimization Algorithm and Neural Networks

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Computers, materials & Continua 2022年第6期71卷 4749-4766页

作者： Sanaa A.A.Ghaleb mumtazimah mohamad Syed Abdullah fadzli waheed A.h.m.Ghanem faculty of Informatics and Computing Universiti Sultan Zainal AbidinKuala Terengganu22200Malaysia faculty of Ocean Engineering Technology and Informatics Universiti Malaysia TerengganuKuala Terengganu21030Malaysia faculty of Engineering University of AdenAdenYemen faculty of Education(Aden-Saber) University of AdenAdenYemen

Spam has turned into a big predicament these days,due to the increase in the number of spam emails,as the recipient regularly receives piles of *** only is spam wasting users’time and *** addition,it limits the storage space of the email box as well as the disk ***,spam detection is a challenge for individuals and organizations *** advance spam email detection,this work proposes a new spam detection approach,using the grasshopper optimization algorithm(GOA)in training a multilayer perceptron(mLP)classifier for categorizing emails as ham and ***,mLP and GOA produce an artificial neural network(ANN)model,referred to(GOAmLP).Two corpora are applied Spam Base and UK-2011Web spam for this ***,the finding represents evidence that the proposed spam detection approach has achieved a better level in spam detection than the status of the art.

关键词： Grasshopper optimization algorithm multilayer perceptron artificial neural network spam detection approach