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Study the Entanglement Dynamics of an Anisotropic two-Qubit Heisenberg XYZ System in a magnetic Field

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Journal of Quantum Information Science 2017年第4期7卷 160-171页

作者： A. R. mohammed t. m. el-shahat mathematics Department Faculty of Science Al-Azhar University Cairo Egypt

We investigate the entanglement dynamics of an anisotropic two-qubit Heisenberg XYZ system with Dzyaloshinskii-moriya (Dm) interaction in the presence of both inhomogeneity of the external magnetic field b and intrinsic decoherence which has been studied. the behavior of quantum correlation and the degree of entanglement between the two subsystems is quantified by using measurement-induced disturbance (mID), negativity (N) and Quantum Discord (QD), respectively. It is shown that in the presence of an inhomogeneity external magnetic field occur the phenomena of long-lived entanglement. It is found that the initial state is the essential role in the time evolution of the entanglement.

关键词： Different Dzyaloshinski-moriya Interactions Entanglement Decoherence

Effect of Y^(3+), Gd^(3+) and La^(3+) dopant ions on structural, optical and electrical properties of o-mullite nanoparticles

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Journal of Rare Earths 2014年第1期32卷 37-42页

作者： m.m.S.Sanad m.m.Rashad E.A.Abdel-Aal m.F.el-shahat K.Powers Central metallurgical R & D Institute Particle Engineering Research Center University of Florida Faculty of Science Ain Shams University

Dielectric ceramics of m（x）Al6（1-x）Si2O13 doped mullite were synthesized via co-precipitation technique. the X-ray diffrac-tion profiles revealed that these nanoparticles were crystallized well and the volume of mullite unit cell was increased as a function of the ionic radius of dopant ion. tEm images showed regular orthorhombic crystal morphology for the pure mullite sample. meanwhile, the doped samples exhibited slightly distorted crystal morphology of larger particle sizes. DSC thermograms evinced that the exo-thermic peak temperature of mullite was shifted to the lower value with m3＋ion insertion. the photoluminescence spectra were stud-ied for mullite samples, and it was found that the intensity of the emission spectra was affected by the m3＋ion type. It was found that, Y3＋doped mullite achieved the minimum dielectric loss value of 0.01 in the radio wave frequency region （1 mHz）. meanwhile, Gd3＋doped mullite achieved the minimum dielectric loss value of 0.09 in the microwave frequency region （1 GHz）.

关键词： rare earths doped mullite photoluminescence crystallization temperature dielectric ceramics

Alternating current characterization of nano-Pt(Ⅱ)octaethylporphyrin(PtOEP) thin film as a new organic semiconductor

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Chinese Physics B 2016年第6期25卷 426-432页

作者： m Dongol m m el-Nahass A el-Denglawey A A Abuelwafa t Soga Nano and thin Film Laboratory Physics DepartmentFaculty of ScienceSouth Valley University Physics Department Faculty of EducationAin Shams University Physics Department Faculty of Applied Medical ScienceTaif University Department of Frontier materials Nagoya Institute of Technology

Alternating current（AC） conductivity and dielectric properties of thermally evaporated Au/Pt OEP/Au thin films are investigated each as a function of temperature（303 K–473 K） and frequency（50 Hz–5 mHz）.the frequency dependence of AC conductivity follows the Jonscher universal dynamic *** AC-activation energies are determined at different *** is found that the correlated barrier hopping（CBH） model is the dominant conduction *** variation of the frequency exponent s with temperature is analyzed in terms of the CBH *** barrier height Wm,hopping distance Rω,and the density of localized states N（EF） are valued at different *** constant ε1（ω,t） and dielectric loss ε2（ω,t） are discussed in terms of the dielectric polarization *** dielectric modulus shows the non-Debye relaxation in the *** extracted relaxation time by using the imaginary part of modulus（m’’）is found to follow the Arrhenius law.

关键词： PtOEP thin films AC conductivity dielectric constants organic semiconductors solar cell nano materials

Valorization of sustainable vegetable oil deodorizer distillate as a novel fatliquor

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Collagen and Leather 2023年第3期5卷 60-72页

作者： el-shahat H.A.Nashy Adel Gabr Abdel-Razek minar mahmoud m.Hassanein Ghada A.Abo-elwafa Hamed elsayed Chemical Industries Research Institute National Research CentreDokkiCairo 12622Egypt Department of Fats and Oils National Research CentreDokkiCairo 12622Egypt

the deodorizer distillate(DD)is a byproduct of vegetable oil processing industry and is rich in functional bioactive *** study aimed to employ phosphorylation modification for DD to produce a new sustainable *** bioactive ingredients in DD,namely fatty acids,sterols,and tocopherols,were determined by using HPLC and *** results revealed that the DD sample contained a high percentage of unsaturated fatty acids(72.3%)and high levels ofγandδ-tocopherols(54.8%and 31.60%,respectively).mechanical parameters(tensile strength,elongation at break,and tear strength)of leather were improved after being treated with the prepared fatliquor ***,SEm showed that the texture of the fatliquored leather had been remarkably ***,the fatliquored leather possessed effective antibacterial effect against the specified+ve,-ve bacteria,and Candida albicans *** strength,fullness,soft handle,and elasticity of leather were all improved,and the grain of leather was protected from becoming loose after drying.

关键词： Vegetable oil Deodorizer distillate Bioactive components Fatliquor Phosphorylation Chrome tanned leather

CO oxidation and 4-nitrophenol reduction over ceria-promoted platinum nanoparticles impregnated with ZSm-5 zeolite

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Journal of Rare Earths 2022年第8期40卷 1247-1254页

作者： Zeinhom m.el-Bahy mohammed t.Alotaibi Salah m.el-Bahy Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City11884CairoEgypt Department of Chemistry Turabah University CollegeTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

Active new ceria-promoted platinum supported on ZSm-5 catalysts were prepared and characterized by X-ray diffraction(XRD),Fourier transform infrared spectra(FtIR),transform electron microscopy(tEm),temperature programmed desorption(tPD),and FtIR of CO *** samples were prepared by the incipient wetness impregnation method and calcined at 500℃.the XRD patterns and FtIR spectra prove that the zeolite framework is kept unaltered after metal *** images prove the presence of Pt nanoparticles with particle size starting from 14 to 27 *** FtIR data suggest the formation of Pt-O-Ce ***-situ FtIR of CO adsorption over reduced samples proves the presence of Pt~0 only,and no Pt^(n+)-CO species are *** prepared catalysts were tested in both oxidation reaction(CO oxidation) in the gas phase and in reduction reaction(4-nitrophenol reduction) in the aqueous ***,CO oxidation by O_(2) results in the formation of a CO_(2) peak at 2347 cm^(-1) as the only CO oxidation product in the studied frequency *** intensity of the CO_(2) peak increases after the addition of Ce,and it is 4 times higher in Pt_(1) Ce_(0.5)ZSm-5 than that in the Ce-free *** to the FtIR data and previous reports,the increase in the catalytic activity may be due to the formation of Pt-O-Ce ***,Ce-promoted Pt_(1) ZSm5 also exhibits enhanced catalytic activity towards the reduction of 4-nitrophenol to 4-aminophenol by NaBH_(4) in the aqueous *** first-order rate constant of the reduction increases ≈13 times after incorporating equal ratios of Pt and Ce(Pt_(1) Ce_(1)ZSm-5),and the activation energy(E_(a)) decreases to 40% of that in the reaction over Pt_(1) ZSm-5.

关键词： 4-Nitrophenol CO oxidation tPD-CO Platinum-cerium ZSm-5 Rare earths

Effects of penicillamine, hypotaurine, and epinephrine on motility, hyperactivity, acrosome reaction of fresh ram sperm

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Asian pacific Journal of Reproduction 2017年第6期6卷 283-288页

作者： K.H.el-shahat m.I.taysser m.R.Badr K.A.Zaki Department of theriogenology Faculty of Veterinary MedicineCairo University Department of Animal Reproduction and Artificial Insemination Reproduction Research Institute Agriculture Research CenterEgypt el-Shieh Zaied Veterinary Clinic Egypt

Objective:to determine the effects of different concentrations of penicillamine, hypotaurine, and epinephrine (PHE) as well as incubation time on motility, hyperactivity and acrosome reaction (AR) of ram spermin ***: Freshly ejaculated spermatozoa from three ram were collected, pooled and subjected to swim up technique in modified sperm tyrode's albumin lactate pyruvate medium supplemented with different concentrations of PHE (10, 20, 30, 40, 50, 75 and 100 mm/mL). then best concentrations were compared and examined for motility, hyperactivity and ***: A high concentrations of PHE (30, 40, 50, 75 and 100mm/mL) showed a significant increase in motility when compared to control immediately after dilution and exist for the first and second hour of incubation period. However, when longer incubation time were used, a significant (Pmotility was achieved. Similar finding was observed in hyperactivity. Stained semen samples showed a maximum percentage of incomplete AR after 1 h incubation corresponding to 50 and 75 mm/mL of PHE;however, spermatozoa treated with 75 mm/mL had a higher tendency to undergo complete AR after further incubation up to 4 h. A dose dependent relationship was detected where the maximum value of total AR was shown in spermatozoa treated with 75 mm/mL PHE for 4 h. Conclusions: to obtain better motility, hyperactivity and AR, treatment of ram spermatozoa with 75 mm/mL PHE for 4 h before being used in insemination was considered the best concentration of PHE to be used in the process ofin-vitro fertilization.

关键词： Ram sperm Capcitation Hyperactivation Acrosome reaction PHE VF

Separation of rare earth elements from sulfate leach liquor by heterocyclic nitrogen compound

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Journal of Rare Earths 2008年第4期26卷 544-551页

作者： GHADA m. mahmoud NABIL t. el Hazek AHmAD m. Farag OmNEYA m. el Hussaini Nuclear materials Authority P.O. Box 530 El Maadi Cairo Egypt Chemistry department Faculty of Science Cairo University Giza Egypt

Separation of rare earth dements by solvent extraction has actually been widely used in various fields from analytical chemistry to hydrometallurgy. A representative ore sample obtained from Kadabora Batholiths-Eastern Desert of Egypt, containing the multiple oxides rare earth minerals： Samarskite, Fergusonite, Betafite, and Pyrochlore, was subjected to sulfuric acid leaching. Different sets of equilibrium loading experiments were carded out on a bench scale for the extraction of rare earths （cerium and yttrium） from the sulfate leach liquor using 8,9-dihydro[1,2,4]triazolo[1,5-a]quinazolin-6（tH）-one {tQ} dissolved in methylene chloride. Stripping was carded out by 20% sodium hydroxide. A rare earth cake was produced by oxalic acid precipitation. Its purity reached 87.3%.

关键词： triazolopyrimidine extraction stripping precipitation rare earths

transport Properties of Bi_2S_3 Single Crystals

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Journal of materials Science & technology 2008年第5期24卷 757-760页

作者： H.t.Shaban m.m.Nassary m.S.el-Sadek Physics Department Faculty of ScienceSouth Valley Univ.QenaEgypt.

Bi2S3 single crystals were grown by using a modification of Bridgman method. measurements of the electrical conductivity, Hall effect and thermoelectric power （tEP） were preformed in two crystallographic directions （parallel and perpendicular to the c-axis）. the measurements showed that the electrical conductivity, Hall mobility, and Seebeck coefficient have anisotropic nature. From these measurements some physical parameters were estimated and the crystals showed n-type of conduction mechanism. Also, values of the energy gap were found to be different in the two directions.

关键词： Bi2S3 Hall effect thermoelectric power electrical conductivity

electronic and magnetic properties of V-and Cr-doped zinc-blende AlN

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Communications in theoretical Physics 2021年第12期73卷 168-175页

作者： t el-Achari F Goumrhar L B Drissi m Drissi el Bouzaidi R Ahl Laamara LPHE-modeling and Simulations Faculty Of SciencesMohammed V University in RabatMorocco Centre of Physics and mathematics CPM-MoroccoMohammed V University in RabatMorocco Higher School of Education and training of el Jadida(ESEF) Chouaib Doukkali UniversityEl JadidaMorocco Laboratoire des Sciences de l’lngenieur pour l’Energie Ecole Nationale des Sciences Appliquees d El Jadida(ENSA-J)BP 1166EL Jadida Plateau24002Morocco College of Physical and Chemical Sciences Hassan II Academy of Sciences and TechnologyKm 4Avenue Mohammed VIRabatMorocco National School of Architecture of tetouan(ENA) Abdelmalek Essaadi UniversityTetouanMorocco

the electronic and magnetic properties of the zinc-blende aluminum nitride doped with V and Cr are studied using the density functional theory(DFt),namely the KKR-CPA-PBE *** Al N is found to be a wide band gap semiconductor,and doping V and Cr single impurities generate ferromagnetic half-metallic ***,the values of the formation energy reveal that these compounds are stable systems for all dopant concentrations.A self-consistent energy minimization scheme determines the ferromagnetic state as the stable magnetic state for V-and Cr-doping Al N.A double exchange mechanism is identified as the mechanism responsible for magnetism in our *** increasing doping impurities,the total magnetic moments increase linearly and the Curie temperature tC,calculated using the mean-field approximation,shows a significant *** present findings reveal Cr-and V-doped zincblende Al N as potential candidates for high Curie temperature ferromagnetic materials.

关键词： AlN compounds CPA-KKR-GGA method Curie temperature Ferromagnetic half-metals tm dopants