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Generalized Green Correspondence of Graded Modules

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Chinese Annals of Mathematics,series B 2009年第4期30卷 413-420页

作者： salah el-Din s. HUssEIN Department of Mathematics Faculty of Science Ain Shams University Abasaya-Cairo 11566 Egypt.

The author studies the Green correspondence and quasi-Green correspondence for indecomposable modules over strongly graded rings. The motivation is to investigate the influence of induction and restriction processes o... 详细信息

关键词： Vertices sources Graded rings Graded modules Green correspondence

Cylindrical Three-Dimensional Dust-Ion Acoustic Propagation in Plasmas

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Communications in Theoretical Physics 2018年第9期69卷 325-330页

作者： s.K.el-Labany E.K.el-shewy H.N.Abd el-Razek A.A.el-Rahman Theoretical Physics Group Faculty of Science Domietta University Department of Physics Taibah University Theoretical Physics Group Faculty of Science Mansoura University Department of Physics Faculty of Science Assiut University

Wave properties of solitons in an unmagnetized four-component dusty plasma system contains isothermal distributed electrons, mobile ions, and negative-positive dusty grains have been examined. To study DIA wave properties,a reductive perturbation (RP) analysis is used. By a reductive perturbation (RP) analysis under convenient coordinate transformation, the three dimension Kadomtsev-Petviashvili equation in cylindrical coordinates is obtained. The effects of dust grain charge on soliton pulse structures are studied. More specifically, solitary profile depending on the axial,radial, and polar angle coordinates with time is discussed. This investigation may be viable in plasmas of the Earth’s mesosphere.

关键词： dust plasmas 3D-CKP equation dusty-ion acoustic solitary waves isothermal electrons

Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease

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Neural Regeneration Research 2025年第1期20卷 174-180页

作者： Yinglong Miao Michael s.Wolfe Computational Medicine Program and Department of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal Chemistry University of KansasLawrenceKSUSA

γ-secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as ***,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-*** this review,we focus on recent studies of structural dynamic mechanisms ofγ-*** mechanisms,including the“Fit-stay-Trim,”“sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental *** approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-*** addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations

关键词： Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics Notch

Hydrothermal Characteristics of Blended Cement Pastes Containing silica sand Using Cement Kiln Dust as an Activator

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Journal of Materials science & Technology 2002年第5期18卷 474-478页

作者： s.A.Abo-el-Enein F.I.el-Hosiny E.el-shimy T.A.Osman Faculty of sci. Ain Shams Univ. Abbassia-Cairo Egypt Building Res. Cent. Cairo P. O. Box 1770 Egypt

The hydrothermal reactivity of silica sand was studied using cement kiln dust (CKD) as an activator in addition to the Portland cement fraction of el-Karnak cement (a blend of ordinary Portland cement and ground sand). Autoclaved EI-Karnak cement pastes were studied at pressures of 0.507, 1.013 and 1.520 MPa of saturated steam with respect to their compressive strength, kinetics of hydrothermal reaction and the phase composition of the formed hydrates. The role of CKD in affecting the physicochemical and mechanical properties of EI-Karnak cement pastes was studied by autoclaving of several pastes containing 5, 7.5, 10 and 20% CKD at a pressure of 1.013 MPa of saturated steam. CKD was added either as a raw CKD (unwashed) or after washing with water (washed CKD). The results of these physicochemical studies obtained could be related as much as possible to the role of CKD (raw or washed) in affecting the hydrothermal reactivity of silica sand in EI-Karnak cement pastes.

关键词： Blended cement silica Cement kiln dust Hydrothermal characteristics

some Factorization Properties in A+B[Г^(*)]Domains

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Algebra Colloquium 2020年第3期27卷 643-650页

作者： E.Boulayat s.el Baghdadi Department of Mathematics Beni Mellal University FSTP.O.Box 523Beni MellalMorocco

Let A■B be an extension of integral domains andГa commutative,additive,cancellative,torsion-free monoid with T∩-Г=el.Let B[Г]be the semigroup ring ofГover B and setГ^(*)=Г\el.Then R=A+B[Г^(*)]is a subring of B[Г].We investigate various factorization properties which are weaker than unique factorization in the domainsof the form A+B[Г^(*)].

关键词： monoid factorization atomic ACCP BFD

The micropolar fluid model for blood flow through a tapered artery with a stenosis

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Acta Mechanica sinica 2008年第6期24卷 637-644页

作者： Kh.s.Mekheimer M.A.el Kot Department of Mathematics Faculty of ScienceAl-Azhar UniversityNasr CityCairo 11884Egypt Department of Mathematics Faculty of EducationSuez Canal UniversitySuezEgypt

A micropolar model for axisymmetric blood flow through an axially nonsymmetreic but radially symmetric mild stenosis tapered artery is presented. To estimate the effect of the stenosis shape, a suitable geometry has been considered such that the axial shape of the stenosis can be changed easily just by varying a parameter （referred to as the shape parameter）. The model is also used to study the effect of the taper angle Ф. Flow parameters such as the velocity, the resistance to flow （the resistance impedance）, the wall shear stress distribution in the stenotic region and its magnitude at the maximum height of the stenosis （stenosis throat） have been computed for different values of the shape parameter n, the taper angle Ф, the coupling number N and the micropolar parameter m. It is shown that the resistance to flow decreases with increasing the shape parameter n and the micropolar parameter m while it increases with increasing the coupling number N. so, the magnitude of the resistance impedance is higher for a micropolar fluid than that for a Newtonian fluid model. Finally, the velocity profile, the wall shear stress distribution in the stenotic region and its magnitude at the maximum height of the stenosis are discussed for different values of the parameters involved on the problem.

关键词： Micropolar fluid Blood flow Tapered artery

Major and trace elemental analysis in milk powder by inductively coupled plasma-optical emission spectrometry(ICP-OEs) and instrumental neutron activation analysis(INAA)

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Journal of Environmental sciences 2003年第4期15卷 570-576页

作者： A.sroor N.Walley el-Dine A.el-shershaby A.s.Abdel-Haleem NuclearPhysicsLaboratory NuclearPhysicsLaboratoryNuclearPhysicsLaboratoryHotLaboratories FacultyofGirlsAinShamsUniversityCairoEgyptFacultyofGirlsAinShamsUniversityCairoEgyptFacultyofGirlsAinShamsUniversityCairoEgyptAtomicEnergyAuthorityCairoEgypt

Major and trace element in seven different kinds of milk powder were studied. The concentration of 24 elements were determined by ICP OEs method, from these elements 9 elements determined by INAA. The determination of trace element contents of foodstuffs, especially milk as daily drink for all peoples age which being a complex food has great importance. The elemental analysis of milk is important both as an indicator of environmental contamination and because milk is a significant pathway for toxic metal intake and a source of essential nutrients for humans. The major elements are Ca, K, Mg, Na, P and s. While trace element are B, Ba, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, sb, se, sn, sr, V, W and Zn. ICP OEs technique is shown to be a powerful tool for trace determinations in powder samples. This is shown by its use for analysis of a series of the milk powders mentioned and comparative results of other direct technique such as instrumental neutron activation analysis. Analysis of both standard reference material A 11 milk powder and NBs Orchard leaves for quality accurance had been completed, and used for a relative method calculate. The importance of the major and trace elements to human health was discussed.

关键词： milk powder ICP OEs INAA

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.

Improved RC6 Block Cipher Based on Data Dependent Rotations

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Computers, Materials & Continua 2022年第1期70卷 1921-1934页

作者： Osama s.Faragallah Ibrahim F.elashry Ahmed AlGhamdi Walid el-shafai s.el-Rabaie Fathi E.Abd el-samie Hala s.el-sayed Mohamed A.elaskily Department of Information Technology College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of electrical Communications Faculty of EngineeringKafrelsheikh UniversityKafrelsheikhEgypt Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of electronics and electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Department of electrical Engineering Faculty of EngineeringMenoufia UniversityShebin El-Kom32511Egypt Department of Informatics Electronic Research Institute(ERI)CairoEgypt

This paper introduces an Improved RC6(IRC6)cipher for data encryption based on data-dependent *** proposed scheme is designed with the potential of meeting the needs of the Advanced Encryption standard(AEs).Four parameters are used to characterize the proposed *** parameters are the size of the word(w)in bits,the number of rounds(r),the length of the secret key(b)in bytes,and the size of the block(L)in *** main feature of IRC6 is the variable number of working registers instead of just four registers as in RC6,resulting in a variable block size for plaintext and *** IRC6 cipher is designed to improve the robustness against attacks by increasing the diffusion for each round and providing greater security with fewer *** effectiveness of the proposed IRC6 scheme is verified against theoretical *** proposed IRC6 scheme depends on full diffusion and confusion mechanisms regardless of the utilized block *** proposed IRC6 scheme saves 70%of the encryption time and 64%of the decryption time of *** simulation results prove that the IRC6 achieves a better encryption/decryption time compared to the ***,the proposed IRC6 is anticipated to fulfill the market needs and system security requirements.

关键词： Cryptography block cipher RC6,IRC6,AEs