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Investigation on high-volume fly ash pastes modified with micro-size metakaolin subjected to high temperatures

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Journal of Central South University 2020年第1期27卷 231-241页

作者： alaa m RASHAD Building materials Research and Quality Control Institute Housing & Building National Research Center (HBRC) Civil Engineering Department College of engineering Shaqra University

Portland cement(PC) containing high-volume fly ash(HVFA) is usually used to obtain economical and more sustainable merits, but these merits suffer from dramatically low compressive strength especially at early ages. In this work, the possibility of using micro-size metakaolin(mSK) particles to improve the compressive strength of HVFA paste before and after subjecting to high temperatures was studied. To produce HVFA paste, cement was partially substituted with 70% fly ash(FA), by weight. After that, FA was partially substituted with mSK at ratios fluctuating from 5% to 20% with an interval of 5%, by weight. The effect of mSK on the workability of HVFA mixture was measured. After curing, specimens were subjected to different high temperatures fluctuating from 400 to 1000 ℃ with an interval of 200 ℃ for 2 h. The results were analyzed by different techniques named X-ray diffraction(XRD), thermogravimetry(TGA) and scanning electron microscopy(SEm). The results showed that the incorporation of mSK particles into HVFA mixture exhibited a negative effect on the workability and a positive effect on the compressive strength before and after firing.

关键词： high-volume fly ash micro-size metakaolin high-temperature property workability remaining compressive strength

One-pot multicomponent Synthesis, Spectroscopy, Crystal Structures and Theoretical Calculations of 3-Cyano-4-(4-hydroxy-3-methoxyphenyl)-6-phenyl-2(1H)-pyridinone and 3-Cyano-4-chlorophenyl-6-(4-tolyl)-2(1H)-pyridinone

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Chinese Journal of Structural Chemistry 2019年第3期38卷 448-463页

作者： mUHAmmAD Nadeem Arshad HASSAN m.Faidallah ABDULLAH m.Asiri osman I.osman FAISAL m.S.Aqlan Chemistry Department Faculty of Science King Abdulaziz University Centre of Excellence for Advanced materials Research (CEAmR) King Abdulaziz University Department of Chemistry University of Jeddah Department of Chemistry University of IBB

Pyridinone derivatives are of great interest in medicinal chemistry where they were found to be potent to various diseases. Their metal complexes added more value to their applications. Here, we have synthesized two 2-pyridinone derivatives(3-cyano-4-(4-hydroxy-3-methoxyphenyl)-6-phenyl-2(1 H)-pyridinone and 3-cyano-4-chlorophenyl-6-(4-tolyl)-2(1 H)-pyridinone) using one-pot multicomponent system. They were well characterized using spectroscopic techniques like nuclear magnetic resonance(NmR-1 H & 13 C), Fourier transform infrared(FT-IR) and UV/Vis spectroscopy. The final structures were determined using single-crystal X-ray diffraction technique which helps us to determine their geometries. Density functional theory(DFT) and time-dependent density functional theory(TD-DFT) with suitable basis-sets of calculations have correctly simulated these spectroscopic parameters. The intramolecular charge transfer(ICT) of both substrates has been discussed using natural bond orbital(NBO) technique. molecular electrostatic potential(mEP) surfaces showed their reactive locations for intermolecular charge transfer. Compared to p-nitroaniline(pNA), both substrates were shown to have substantial molecular hyperpolarizability.

关键词： crystal structures NBO one-pot multicomponent system 2-pyridinone TD-DFT

Some aspects affecting the response of RC compartment structures subjected to internal blast loads

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Earthquake Engineering and Engineering Vibration 2022年第1期21卷 135-148页

作者： osman m.O.Ramadan m.Galal El Sherbiny Ahmed m.Khalil Faculty of Engineering Cairo UniversityCairo 12411Egypt Higher Technological Institute(HTI)at 10th of Ramadan City Sharqia 13658Egypt Structural Engineering and Construction management Department Faculty of Engineering&TechnologyFutureUniversity in Egypt-FUECairo 16383Egypt

Protective compartments are typically used to protect some specific structures from internal explosions,such as industrial buildings that contain devices that may explode in certain *** research investigates how the response of reinforced concrete(RC)compartment structures subjected to internal blast loads are affected by the following aspects:introduction of material nonlinearity in the analysis,reinforcement ratio,and aspect ratio of the *** achieve this goal,a calibrated and sophisticated FE numerical model is introduced,and a parametric study for the intended aspects is carried out.A discussion of the results and conclusions are offered,which show the role of each aspect in the dynamic performance of the compartment *** main conclusions are as follows:introduction of material nonlinearity in this type of analysis and for these structures is very important and significant in obtaining accurate outputs that are similar to actual behavior;the reinforcement ratio has a significant effect on the response and its effect varies depending on the thickness of the compartment;in general,increasing the reinforcement ratio enhances the behavior and reduces the stresses in the compartment;and the aspect ratio of the compartment does not show a clear pattern on the response of such structures under internal blast loads.

关键词： blast loads protective structures nonlinear analysis explicit dynamic analysis

The Tauride Ophiolites of Anatolia(Turkey):A Review

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Journal of Earth Science 2016年第6期27卷 901-934页

作者： osman Parlak Cukurova On Universitesi Jeoloji Muhendisligi Bolumu Balcah Adana 01380 Turkey

The Tauride ophiolites lie on the northern and southern flanks of an E-W-trending Tanride carbonate platform. They mainly consist of three tectonic units namely in ascending order, ophiolitic melange, sub-ophiolitic metamorphic sole and oceanic lithospheric remnants. They were generated above intra-oceanic subduction zones and emplaced over the Tauride carbonate platform from different Neotethyan oceanic basins in the Late Cretaceous. Tauride ophiolites from west to east are described and reviewed. All are underlain by well-preserved dynamothermal metamorphic soles of varied structural thicknesses up to 500 m that have a constant structural position between ophiolitic melange below and harzburgitic mantle tectonites above and display typical inverted metamorphic sequences from amphibolite facies above to greenschist facies below. The metamorphic soles are shown to have evolved during the initiation of subduction and emplacement processes. In the PozantlKarsantl area the contact between the metamorphic sole and the overlying serpentinized harzburgites is characterized by a 1.5-2-m-thick zone of sheared serpentinized harzburgitic mantle intercalated with amphibolites and cut by thick mafic dykes （7-8 m） which postdate intraoceanic metamorphism and high-temperature ductile deformation. This contact is interpreted as an intra-oceanic decoupling surface along which volcanics from the upper levels of the down-going plate were metamorphosed to amphibolite facies and accreted to the base of the hanging wall plate. The metamorphic soles and overlying ophiolitic rocks were intruded by numerous isolated post-metamorphic diabase dykes filled by island arc tholeiitic magma. Subduction initiation and roll-back processes best explain the structural and petrological relationships of Late Cretaceous ophiolite genesis, metamorphic sole formation and subsequent dyke emplacement of the Tauride ophiolites.

关键词： ophiolite metamorphic sole dyke emplacement roll-back subduction initiation.

Relaxation theory of spin-3/2 Ising system near phase transition temperatures

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Chinese Physics B 2010年第8期19卷 257-269页

作者： osman Canko mustafa Keskin Department of Physics Erciyes University

Dynamics of a spin-3/2 Ising system Hamiltonian with bilinear and biquadratic nearest-neighbour exchange interactions is studied by a simple method in which the statistical equilibrium theory is combined with the Onsager＇s theory of irreversible thermodynamics. First, the equilibrium behaviour of the model in the molecular-field approximation is given briefly in order to obtain the phase transition temperatures, i.e. the first- and second-order and the tricritical points. Then, the Onsager theory is applied to the model and the kinetic or rate equations are obtained. By solving these equations three relaxation times are calculated and their behaviours are examined for temperatures near the phase transition points. moreover, the z dynamic critical exponent is calculated and compared with the z values obtained for different systems experimentally and theoretically, and they are found to be in good agrement.

关键词： spin-3/2 Ising system 0nsager theory

Information security through controlled quantum teleportation networks

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Digital Communications and Networks 2020年第4期6卷 463-470页

作者： Hala Hamdoun alaa Sagheer Center for Artificial Intelligence and RObotics(CAIRO) Department of Computer ScienceAswan UniversityAswanEgypt Department of Computer Science College of Computer Science and Information TechnologyKing Faisal UniversitySaudi Arabia

Information security is the backbone of current intelligent systems,such as the Internet of Things(IoT),smart grids,and machine-to-machine(m2m)*** increasing threat of information security requires new models to ensure the safe transmission of information through such ***,quantum systems have drawn much attention since they are expected to have a significant impact on the research in information *** paper proposes a quantum teleportation scheme based on controlled multi-users to ensure the secure information transmission among *** teleportation is an original key element in a variety of quantum information tasks as well as quantum-based technologies,which plays a pivotal role in the current progress of quantum computing and *** the proposed scheme,the sender transmits the information to the receiver under the control of a third user or ***,we show that the efficiency of the proposed scheme depends on the properties of the transmission channel and the honesty of the *** with various teleportation scheme presented recently in the literature,the most important difference in the proposed scheme is the possibility of suspicion about the honesty of the controller and,consequently,taking proper precautions.

关键词： Information security machine-to-machine communication Intelligent secure systems Quantum teleportation Quantum networks

Chromium Substitution Effect on the magnetic Structure of Iron Oxides

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Chinese Physics Letters 2012年第5期29卷 217-220页

作者： osman murat Ozkendir mersin University Tarsus Technical Faculty of EducationTarsusTurkey UVSOR FacilityInstitute for Molecular ScienceOkazaki 444-8585Japan

The local magnetic and electronic structures of chromium substituted iron oxide polycrystalline samples are investigated via Fe L-edge x-ray absorption near-edge structural and magnetic circular dichroism measurements.A strong dependence of atomic magnetic levels on the applied external magnetic field is *** magnetic behavior of Cr-doped iron oxides are determined to be dominantly governed by the d-d hybridization between Fe and Cr valence *** addition,the formation of CrO_(2) and Cr_(2)O_(3) chromium oxide clusters in the sample are observed to determine the magnetic ordering,***-ferromagnetic or ferromagnetic with the changing external magnetic *** results highly agree with the previous studies.

关键词： chromium ferromagnetic magnetic

multi-solitons of Thermophoretic motion Equation Depicting the Wrinkle Propagation in Substrate-Supported Graphene Sheets

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Communications in Theoretical Physics 2019年第4期71卷 362-366页

作者： Ahmad Javid Nauman Raza m.S.osman Department of mathematics University of the Punjab Quaid-e-Azam Campus Department of mathematics Faculty of Science Cairo University Department of mathematics Duba University College University of Tabuk

The paper addresses the thermophoretic motion(Tm) equation, which is serviced to describe soliton-like thermophoresis of wrinkles in graphene sheet based on Korteweg-de Vries(KdV) equation. The generalized uni?ed method is capitalized to construct wrinkle-like multiple soliton solutions. Graphical analysis of one, two, and threesoliton solutions is carried out to depict certain properties like width, amplitude, shape, and open direction are adjustable through various parameters.

关键词： thermophoretic motion equation generalized unified method multiple soliton solution graphene sheets

Yields of projectile fragments in sulphur-emulsion interactions at 3.7 A GeV

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Chinese Physics C 2017年第5期41卷 97-103页

作者： S.Kamel W.osman m.Fayed Physics Department Faculty of EducationAin Shams University Physics Department Faculty of ScienceCairo University

This work presents the basic characteristics of singly,doubly and heavily charged projectile fragments（PFs） emitted in inelastic interactions of ^（32）S ions with photo-emulsion nuclei at Dubna energy（3.7 A GeV）.Our experimental data are compared with the corresponding data for other projectiles at the same incident *** study of mean multiplicities of different charged PFs against the projectile mass shows a power-law *** multiplicity distributions of singly and doubly charged PFs have been fitted well with a Gaussian distribution *** yields of PFs broken up from the interactions of ^（32）S projectile nuclei with different target nuclei are *** beam energy dependence in terms of the various order moments is studied as well.

关键词： projectile nuclei emulsion multiplicity charged doubly sulphur emitted nucleus relativistic