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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

Recovery of some valuable elements from lamprophyre dykes in the Abu Rusheid area, Southeastern Desert, Egypt

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Chinese Journal Of Geochemistry 2012年第1期31卷 64-73页

作者： Zaki D.I. Shawky N. el-sheikh E.m. Ahmed F.Y. Ibrahim.m.E. Nuclear materials Authority El MaadiP.O.Box 530 CairoEgypt Chemistry Dept. Faculty of Science for GirlAl-Azhar UniversityEgypt

In the Abu Rusheid area, Southeastern Desert of Egypt, polymineralized (HREEs, U, Zn and Pb) lam-prophyre dykes are recently recorded. The lamprophyre dykes cut cataclastic rocks along share zones in NNW-SSE trends. The secondary U-minerals are essentially represented by uranophane, kasolite, torbernite and autunite. Ex-perimental work was carried out on the lamprophyre dykes for the recovery of uranium and other valuable elements (e.g. Zn, Pb and Al) from 50 kg of technological sample. The optim.m conditions were: 100 g/L sulfuric acid con-centration, 1:5 S/L (solid/liquid) and soaking for 15 days at room temperature. The leaching efficiencies for the re-covery of uranium and other elements like Al, Zn and Pb were 40, 33.6, 98.8 and 78, respectively.

关键词：有价元素煌斑岩岩脉沙漠埃及价值最佳工艺条件实验工作

Some studies of the interaction between two two-level atoms and SU(1,1) quantum systems

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Chinese Physics B 2018年第10期27卷 116-122页

作者： T m el-Shahat m Kh Ismail Faculty of Science Al-Azhar University. Assiut 71524 Egypt

Herein, we present an approach to look for the best phenomenon to measure quantum correlation. The system of two isolated qubits each interacting with a single-mode cavity was theoretically created to study the quantum correlation. Some of the phenomena, such as the quantum discord and concurrence, were generated through such a system. The influences of initial state purity, qubit motion, and detuning parameters were discussed for the phenomena. These parameters for a specific value show that the behavior of phenomena are analogous. It is interesting to mention that some values of detuning undergo a sudden death of phenomena, and the quantum discord still captures the qubits quantum correlation. We predict that the quantum discord may be a better measure of quantum correlation than concurrence.

关键词： an isolated atom with a cavity SU (1,1) quantum discord concurrence

Effect of Conductive Fillers on the Cyclic Stress-Strain and Nano-Scale Free Volume Properties of Silicone Rubber

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Chinese Journal of Polymer Science 2014年第5期32卷 558-567页

作者： m.H.Abd-el Salam S.el-Gamal m.mohsen D.m.Abd el-maqsoud Physics Department Faculty of Education Ain Shams University Physics Department Faculty of Science Ain Shams University

The effect of carbon black （CB） and graphite （G） powders on the macroscopic and nano-scale free volume properties of silicone rubber based on poly（di-methylsiloxane）（PDmS） was studied through thermal and cyclic mechanical measurements, as well as with positron annihilation lifetime spectroscopy （PALS）. The melting temperature of the composites （Tm） and the endothermic enthalpy of melting （ΔHm） were estimated by differential scanning calorimetry （DSC）. Tm and the degree of crystallinity （χc） of PDmS composites were found to decrease with increasing the CB content. This can be explained due to the increase in physical cross-linking which results in a decrease in the crystallite thickness. Besides, χc was found to be dependent on the filler type. Cyclic stress-strain behavior of PDmS loaded with different contents of filler has been studied. mullins ratio （Rm） was found to be dependent on the filler type and content. It was found that, Rm increases with increasing the filler content due to the increase in physical cross-linking which results in a decrease in the size of free volume, as observed through a decrease of the o-Ps lifetime τ3 measured by PALS. moreover, the hysteresis in PDmS-CB composites was more pronounced than in PDmS-G composites. Furthermore, a correlation was established between the free volume Vf and the mechanical properties of PDmS composites containing different fillers. A negative correlation was observed between Vf and Rm.

关键词： Positron annihilation Positronium Free volume Si-rubber Composite Cyclic mechanical properties.

Nuclear radiation shielding effectiveness and corrosion behavior of some steel alloys for nuclear reactor systems

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Defence Technology（防务技术） 2019年第4期15卷 621-628页

作者： m.m. Sadawy R.m. el Shazly mining and Petroleum Engineering Department Al-Azhar University Nasr City Cairo 11371 Egypt Physics Department Faculty of Science Al-Azhar University Nasr City Cairo 11884 Egypt

Different types of nuclear parameters and corrosion behavior were deduced for carbon steel(AISI 1018),austenitic(304 SS),and duplex(2507 SS)stainless steel *** types of neutron energies as well as nine gamma ray energy lines(121.78-1407.92 keV)were used to evaluate the macroscopic neutron cross-sections(∑,cm^-1)and mass attenuation coefficients[σ,cm^2·g^-1)of gamma ray *** corrosion behavior was investigated using different electrochemical *** results showed that the stainless-steel alloys had a good attitude than that of carbon steel alloy for neutron and gamma ray parameters,especially the duplex stainless *** calculated values of mass attenuation coefficient using WinXcom computer program(Version 3.1),exhibited a very good agreement with the experimental values of that ***,the results indicated that duplex stainless-steel exhibited corrosion resistance higher than 304 SS and AISI 1018 steel alloys.

关键词： Steel alloys macroscopic cross-section mass attenuation coefficient Passive film Pitting

Calculation of photon shielding properties for some neutron shielding materials

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Nuclear Science and Techniques 2017年第5期28卷 74-80页

作者： A. m. el-Khayatt Physics Department College of Science Al Imam Mohammad Ibn Saud Islamic University (IMSIU) RiyadhSaudi Arabia Reactor Physics Department NRC Atomic Energy Authority 13759 Cairo Egypt

The objective of the present study is to calculate photon shielding parameters for seven polyethylene-based neutron shielding materials. The parameters include the effective atomic number(Z_(eff)), the effective electron density(N_(eff)) for photon interaction and photon energy absorption,and gamma-ray kerma coefficient(kc). The calculations of Z_(eff)are presented as a single-valued and are energy dependent. While Z_(eff)values were calculated via simplistic powerlaw method, the energy-dependent Z_(eff)for photon interaction(Z_(PI-eff)) and photon energy absorption(Z_(PEA-eff)) are obtained via the direct method for energy ranges of 1 keV–100 GeV and 1 keV–20 me V, respectively. The kccoefficients are calculated by summing the contributions of the major partial photon interactions for energy range of 1 keV–100 meV. In most cases, data are presented relative to pure polyethylene to allow direct comparison over a range of energy. The results show that combination of polyethylene with other elements such as lithium and aluminum leads to neutron shielding material with more ability to absorb neutron and crays. Also, the kerma coefficient first increases with Z of the additive element at low photon energies and then converges with pure polyethylene at energies greater than 100 keV.

关键词： Neutron shielding materials Effective atomic number Kerma coefficient c-rays

Solution-processed quantum dot SnO_(2) as an interfacial electron transporter for stable fully-air-fabricated metal-free perovskite solar cells

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Journal of materiomics 2022年第6期8卷 1172-1183页

作者： Rabie m.Youssef A.m.S.Salem Ahmed Shawky Shaker Ebrahim.moataz Soliman mohamed S.A.Abdel-mottaleb Said m.el-sheikh Nanostructured materials and Nanotechnology Department Advanced Materials InstituteCentral Metallurgical Research and Development Institute(CMRDI)P.O.Box:87HelwanCairo11421Egypt Nano-Photochemistry and Solar Chemistry Labs. Department of ChemistryFaculty of ScienceAin Shams UniversityAbbassiaCairoEgypt Department of materials Science Institute of Graduate Studies and ResearchAlexandria UniversityEgypt

Perovskite solar cells could strongly compete with the silicon solar cells in the market soon as illustrated in recent *** this work,promising and stable metal-free perovskite solar cells(PSCs)has been successfully fabricated using an inorganic SnO_(2)/Quantum dot SnO_(2)(QD-SnO_(2))double layer as an efficient electron transport layer via a low-temperature solution *** fully-air fabricated PSCs in the form of FTO/SnO_(2)/QD-SnO_(2)/CH3NH3PbI3/Carbon were tested at different annealed QD-SnO_(2) between 300 and 500℃.The as-prepared QD-SnO_(2) and the fabricated devices are characterized by various techniques,including XRD,XPS,HR-TEm,FE-SEm,UVeviseNIR spectroscopy,PL,and solar *** prepared QD-SnO_(2) at 300℃ has shown well-ordered nanoparticles of 5.6 nm in diameter with superior carrier density(1.5×10^(15) cm^(-3))and highest carrier mobility(64.1 cm^(2)·V^(-1)·s^(-1)),accelerating the carriers separation process within the *** best devices demonstrated a maxim.m power conversion effi-ciency(PCE)of 11.7%,VOC 0.81 V,JSC 19.5 mA·cm^(-2),and FF 74%.The presence of an interfacial layer of QDSnO_(2) over the blocking SnO_(2) upsurges the band gaps alignment and accelerates the carriers extraction rate affecting the performance of the fabricated perovskite ***,the optimized fabricated devices revealed a shelf stability-life of four months in humid air(40%-50%)with>83%of its initial *** simple synthetic approach can develop the opportunities to transfer the cell from the lab to the market,which will be compatible with large-scale production.

关键词： Solution-processed nanomaterials Perovskite solar cells electron transport layer Thin film Quantum Dot-SnO_(2)

Feasibility of new ladle-treated Hadfield steel for mining purposes

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International Journal of minerals,metallurgy and materials 2018年第3期25卷 300-309页

作者： m.K. el Fawkhry Central metallurgical Research and Development Institute (CmRDI) Box 87 Helwan Egypt

A debate has arisen over the possibility of using a new ladle-treated Hadfield steel instead of conventional heat-treated Hadfield steel in mining applications. This debate might be solved by identifying the differences between the mechanical properties and strain-hardening properties of conventional heat-treated Hadfield steel and its counterpart ladle-treated Hadfield steel. Tensile and compression tests demonstrated that the ductility of ladle-treated Hadfield steel is similar to that of conventional heat-treated steel. However, the strain-hardening property of the ladle-treated Hadfield steel is almost two times higher than that of the heat-treated Hadfield steel. The results of this study demonstrate that the improvement of the strain-hardening behavior is attributable to the low stacking-fault energy of the main austenite matrix, which results from the high segregation coefficient of carbon and manganese solutes of the main austenite matrix into the new eutectic phase. Superior wear abrasion resistance is a potential consequence of different strain-hardening properties under low and high loads.

关键词： Hadfield steel ladle treatment process wear abrasion resistance strain hardening properties mechanical properties

Softζ-Rough Set and Its Applications in Decision making of Coronavirus

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Computers, materials & Continua 2022年第1期70卷 267-285页

作者： m.A.el Safty Samirah Al Zahrani m.K.el-Bably m.el Sayed Department of mathematics and Statistics College of ScienceTaif UniversityTaif21944Saudi Arabia Department of mathematics Faculty of ScienceTanta UniversityTantaEgypt Department of mathematics College of Science and ArtsNajran UniversityNajran66445Saudi Arabia

In this paper,we present a proposed method for generating a soft rough approximation as a modification and generalization of Zhaowen et *** were obtained between our approach and the previous study and ***,an application on Coronavirus(COVID-19)has been presented,illustrated using our proposed concept,and some influencing results for symptoms of Coronavirus patients have been ***,following these concepts,we construct an algorithm and apply it to a decision-making problem to demonstrate the applicability of our proposed ***,a proposed approach that competes with others has been obtained,as well as realistic results for patients with ***,we used mATLAB programming to obtain the results;these results are consistent with those of theWorld Health Organization and an accurate proposal competing with the method of Zhaowen et *** been ***,it is recommended that our proposed concept be used in future decision making.

关键词： Soft set soft rough set softζrough set COVID-19 intelligence discovery decision making

Geochemical and geochronological characteristics of the Um Rus granite intrusion and associated gold deposit,Eastern Desert,Egypt

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Geoscience Frontiers 2020年第1期11卷 325-345页

作者： Basem Zoheir Richard Goldfarb Astrid Holzheid Hassan Helmy Ahmed el sheikh Department of Geology Faculty of ScienceBenha University13518BenhaEgypt Institute of Geosciences University of KielLudewig-Meyn Str.1024118KielGermany State Key Laboratory of Geological Processes and mineral Resources China University of Geosciences(Beijing)Beijing100083China Department of Geology Faculty of ScienceMinia University61519MiniaEgypt Department of Geology Faculty of ScienceSohag UniversityEgypt

The Um Rus tonalite-granodiorite intrusion(~6 km2)occurs at the eastern end of the Neoproterozoic,ENE-trending Wadi muba rak shear belt in the Central Eastern Desert of ***-bearing quartz veins hosted by the Um Rus intrusion were mined intermittently,and initially by the ancient Egyptians and until the early 1900 *** relationship between the gold mineralization,host intrusion,and regional structures has always been *** present new geochemical and geochronological data that help to define the tectonic environment and age of the Um Rus *** addition,field studies are integrated with EPmA and LA-ICP-mS data for gold-associated sulfides to better understand the formation and distribution of gold *** bulk-rock geochemical data of fresh host rocks indicate a calc-alkaline,metaluminous to mildly peraluminous,I-type granite *** trace element composition reflects a tectonic setting intermediate between subduction-related and within-plate environments,presumably transitional between syn-and post-collisional *** crystallization age of the Um Rus intrusion was determined by in situ SHRImP 206 Pb/238 U and 207Pb/235U measurements on accessory monazite *** resultant monazite U-Pb weighted mean age(643±9 ma;mSWD 1.8)roughly overlaps existing geochronological data for similar granitic intrusions that are confined to major shear systems and are locally associated with gold mineralization in the Central Eastrn Desert(e.g.,Fawakhir and Hangaliya).This age is also consistent with magmatism recognized as concomitant to transpressional tectonics(D2:~650 ma)during the evolution of the Wadi mubark *** of the gold-bearing quartz veins in NNE-SSW and N-S striking fault segments was likely linked to the change from transpressional to transtensional tectonics and terrane exhumation(D3:620-580 ma).The development of N-S throughgoing fault arrays and dike swarms(~595 ma)led to heterogeneous deformation and recrystallizat

关键词： Um Rus intrusion Whole-rock geochemistry SHRImP U-Pb monazite dating Gold mineralization LA-ICP-mS data of pyrite and arsenopyrite