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Chinese Physics B 2018年第4期27卷 170-177页

作者： S Golkar m k Tavassoly Atomic and molecular Group Faculty of PhysicsYazd University

Preventing quantum entanglement from decoherence effect is of theoretical and practical importance in the quantum information processing *** this regard,we consider the entanglement dynamics of two identical qubits where the qubits which are coupled to two independent（markovian and/or non-markovian） as well as a common reservoir at zero temperature are further interacted with a classical driving laser ***,we study the preservation of generated two-qubit entanglement in various situations using the concurrence *** is shown that by applying the classical driving field and so the possibility of controlling the Rabi frequency,the amount of entanglement of the two-qubit system is improved in the off-resonance condition between the qubit and the central cavity frequencies（central detuning） in both non-markovian and markovian *** the central detuning has a constructive role,the detuning between the qubit and the classical field（laser detuning） affects negatively on the entanglement *** obtained results show that long-living entanglement in the non-markovian reservoir is more accessible than in the markovian *** demonstrate that,in a common reservoir non-zero stationary entanglement is achievable whenever the two-qubit system is coupled to the reservoir with appropriate values of relative coupling strengths.

关键词： entanglement markovian and non-markovian reservoir Rabi frequency concurrence

Petrology, geochemistry, radioactivity, and m–W type rare earth element tetrads of El Sela altered granites, south eastern desert,Egypt

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Acta Geochimica 2019年第1期38卷 95-119页

作者： A.m.El mezayen m.A.Heikal m.G.El-Feky H.A.Shahin I.k.Abu Zeid S.R.Lasheen Geology Department Faculty of Science Al Azhar University Nuclear material Authority

The southern part of the Eastern Desert of Egypt—about 30 km southwest of Abu-Ramad city—is mainly covered by ophiolitic rocks(Sul Hamed), island arc assemblage, younger granites(muscovite granites of Qash Amer and two mica granites of El Sela), and various acidic and basic dikes. Field, petrological, and geochemical studies indicate that the El Sela shear zone has been subject to hydrothermal and supergene alteration such as kaolinization, albitization, sericitization, and hematitization. It is invaded by quartz ENE–WSW veins associated with hydrothermal alteration accompanied by radioactive mineralization. The investigated younger granitic rocks had very low contents of compatible elements, such as Cr, Ni,and Co; and high contents of incompatible elements, such as Zr, and large ion lithophiles, such as Sr, especially in the El Sela shear zone. major oxide and trace element analyses revealed calc-alkaline affinity and peraluminous *** highly differentiated granitic rocks' lower Zr/Hf and higher Y/Ho than the normal ratio are consistent with hydrothermal alteration. most samples had rare earth element(REE)-patterns with an m-type tetrad effect in the first and fourth segments and a W-type tetrad in the third segment. The average ∑REE in the studied granites was lower than the world granite average; the ratio of light to heavy REEs greater. The main radioactive, uranium-bearing, and uraniferous Fe and mn minerals are uranothorite,autunite, uranophane and autunite as compounds, kasolite,columbite, xenotime, uranophane-bearing zircon and jarosite, silver-bearing pyrite, hematite, and autunite-bearing pyrolusite.

关键词： Geochemistry REE-tetrad effect Radioactive minerals Radiometric measurements Qash Amer El Sela

Clustering Gene Expression Data Through modified Agglomerative m-CURE Hierarchical Algorithm

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Computer Systems Science & Engineering 2022年第6期41卷 1027-1041页

作者： E.kavitha R.Tamilarasan N.Poonguzhali m.k.Jayanthi kannan A Constituent College of Anna University University College of EngineeringVillupuram605103India A Constituent College of Anna University University College of EngineeringPattukkottai614701India Department of Computer Science and Engineering Manakula Vinayagar Institute of TechnologyPuducherry605107India Department of Computer Science Engineering Faculty of Engineering and TechnologyJAIN(Deemed-To-Be University)Bangalore562112India

Gene expression refers to the process in which the gene information isused in the functional gene product synthesis. They basically encode the proteinswhich in turn dictate the functionality of the cell. The first step in gene expressionstudy involves the clustering usage. This is due to the reason that biological networks are very complex and the genes volume increases the comprehending challenges along with the data interpretation which itself inhibit vagueness, noise andimprecision. For a biological system to function, the essential cellular moleculesmust interact with its surrounding including RNA, DNA, metabolites and proteins. Clustering methods will help to expose the structures and the patterns inthe original data for taking further decisions. The traditional clustering techniquesinvolve hierarchical, model based, partitioning, density based, grid based and softclustering methods. Though many of these methods provide a reliable output inclustering, they fail to incorporate huge data of gene expressions. Also, thereare statistical issues along with choosing the right method and the choice of dissimilarity matrix when dealing with gene expression data. We propose to use amodified clustering algorithm using representatives (m-CURE) in this workwhich is more robust to outliers as compared to k-means clustering and also ableto find clusters with size variances.

关键词： Clustering gene identifiers representatives dimension reduction

Effect of Oxygen Admittance Temperature on the Growth of ZnO microcrystals by Thermal Evaporation Technique

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Journal of materials Science & Technology 2012年第4期28卷 317-320页

作者： k.m.k. Srivatsa Deepak Chhikara m. Senthil kumar Physics of Energy Harvesting Division National Physical Laboratory Council of Scientific & Industrial Research (CSIR) New Delhi 110012 India

Hexagonally well-faceted microcrystals of ZnO have been grown by thermal evaporation of Zn powder in oxygen ambient at 700℃ under atmospheric pressure. It has been observed that the properties （size and quality） of ZnO microcrystals have a strong dependence on the reactor temperature at which the oxygen gas is admitted into the growth zone. The microcrystals grown with oxygen admittance at 450℃ have a length of 1 μm and a diameter of 0.75 μm while that grown with oxygen admittance at 600 ℃ have a length of 1.5-2 μm and a diameter of 1 μm. Room temperature photoluminescence spectra show a ultraviolet （UV） emission peak at 385 nm with a green band emission at around 500 nm. The UV-to-green band emission ratio for the microcrystals grown with oxygen admittance at 450℃ is observed to be 1.25 and the ratio decreases to 0.45 for the sample grown with oxygen admittance at 600℃.

关键词： ZnO microcrystals Thermal evaporation Scanning electron microscopy Transmission electron microscopy Room temperature photoluminescence

Synthesis of Anatase Titania Nanostructures at Room Temperature by PECVD Technique

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Journal of materials Science & Technology 2011年第8期27卷 696-700页

作者： k.m.k. Srivatsa Deepak Chhikara m. Senthil kumar materials Physics and Engineering Division National Physical Laboratory Council of Scientific & Industrial Research (CSIR) Physics of Energy Harvesting Division National Physical Laboratory Council of Scientific & Industrial Research (CSIR)

titania nanostructures have been synthesized at room temperature by plasma enhanced chemical vapor deposition （PECVD） process on silicon （100） substrates using titanium tetraisopropoxide [Ti（OC3H7）4, TTIP] vapor, argon and oxygen mixtures under various deposition pressures. The deposited titania has been characterized for its structural, morphological and chemical composition by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray （EDX） spectroscopy and Fourier transform infrared （FTIR） spectroscopy recordings. With the variation of deposition pressure, titania assumes various nanostructures viz. nanocrystals, nanoparticles, noanorods and comb-like structure. EDX and FTIR measurements show that the deposited titania is of high chemical purity. The possible growth mechanisms for the observed titania nanostructures have been discussed.

关键词： Nanostructures Plasma enhanced chemical vapor deposition Anatase titania

Production of dimethylether(DmE) as a clean fuel using sonochemically prepared CuO and /or ZnO- modified γ- alumina catalysts

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燃料化学学报 2014年第3期42卷 350-356页

作者： Sameh m.k.Aboul-Fotouh Ain Shams University Faculty of EducationChemistry Department

The catalytic conversion of methanol to dimethylether(DmE)was studied over CuO/Al2O3,ZnO/Al2O3and ZnOCuO/Al2O3nanocatalysts prepared in presence or absence of ultrasonic *** catalysts were characterized by X-ray diffraction(XRD),surface characterization method(BET),scanning electron microscope(SEm),H2-temperature programmed reduction(H2-TPR)and temperature programmed desorption of ammonia(NH3-TPD).The experimental results show that during catalytic dehydration of methanol to dimethylether,the activities of the CuO/Al2O3,ZnO/Al2O3and ZnO-CuO/Al2O3catalysts prepared using ultrasonic treatment are much higher than those prepared in absence of *** shows that the use of ultrasonication results in much smaller *** and XRD show that the ultrasonication increases the surface area and pore volume of the catalysts.H2-TPR profiles indicated that reducibility of the sonicated nanocatalysts is carried out at lower ***3-TPD shows that ultrasound irradiation has enhanced the acidity of the nanocatalyst and hence enhanced catalytic performance for DmE formation.

关键词： DmE 燃料化学氧化铜氧化锌

Effect of ultrasonic irradiation and /or halogenation on the catalytic performance of γ-Al_2O_3 for methanol dehydration to dimethyl ether

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燃料化学学报 2013年第9期41卷 1077-1084页

作者： Sameh m.k.Aboul-Fotouh Ain Shams University Faculty of EducationChemistry DepartmentRoxyCairo 11566Egypt

Dimethyl ether(DmE) is amongst one of the most promising alternative,renewable and clean fuels being considered as a future energy *** this study,the comparative catalytic performance of the halogenated γ-Al 2 O 3 prepared from two halogen precursors(ammonium chloride and ammonium fluoride) is *** impact of ultrasonic irradiation was evaluated in order to optimize both the halogen precursor for the production of DmE from methanol in a fixed bed *** catalysts were characterized by SEm,XRD,BET and NH *** reaction conditions where the temperature ranged from 200 to 400 ℃ with a WHSV = 15.9 h-1was found that the halogenated catalysts showed higher activity at all reaction ***,the halogenated alumina catalysts prepared under the effect of ultrasonic irradiation showed higher performance of γ-Al 2 O 3 for DmE *** chlorinated γ-Al 2 O 3 catalysts showed a higher activity and selectivity for DmE production than fluorinated versions.

关键词：化学原理方法化学动力学

Preparation of Sm2O3 and Co3O4 from SmCo magnet swarf by hydrometallurgical processing in chloride media

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Journal of Rare Earths 2018年第7期36卷 725-732页

作者： k.Sahoo A.k.Nayak m.k.Ghosh k.Sarangi CSIR-Institute of minerals and materials Technology Bhubaneswar-751013OdishaIndia

The recycling of rare earth elements（REE） from end-of-life REE based products is an environment friendly proposition. Waste Sm-Co based permanent magnet generated during machining is a good source for both Sm and Co. In the present study a simpler process of acid leaching at 80 ℃ followed by solvent extraction, oxalate precipitation and calcination is described for producing pure Sm2 O3 and Co3 O4. With either 10 vol% H2SO4 or 15 vol% HCI at 80 ℃ more than 95% Sm and Co are leached in 1 *** of Sm from sulphate leach liquor with TBP or Aliquat 336 was poor. Although extraction with TOPS-99 is quantitative but Sm from sulphate leach liquor precipitated as Sm2（SO4）3·8 H2O. The chloride leach liquor at an initial pH of 2.5 and with 1.2 mol/L TOPS-99 shows requirement of 4-stages at A：O = 3：2. Stripping with oxalic acid precipitates Sm-oxalate which is calcined at 800 ℃ to produce Sm2 O3. Co3 O4 is recovered from the raffinate through oxalate precipitation followed by calcination at450℃.

关键词： SmCo magnet Samarium Cobalt TOPS-99 Solvent extraction Precipitation stripping

Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 123-138页

作者： Chentong GAO Huiyu SUN Jianping GU W.m.HUANG College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics School of mechanical and Aerospace Engineering Nanyang Technological University Jiangsu key Laboratory of Advanced Structural materials and Application Technology School of Materials Science and EngineeringNanjing Institute of Technology

Currently, there are a limited number of dynamic models available for braided composite plates with large overall motions, despite the incorporation of three-dimensional(3D) braided composites into rotating blade components. In this paper, a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established. Based on kirchhoff's plate assumptions, the displacement variables of the plate are expressed. By incorporating the braiding directions into the constitutive equation of the braided composites, the dynamic model of the plate considering braiding directions is obtained. The effects of the speeds, braiding directions, and braided angles on the responses of the plate with fixed-axis rotation and translational motion, respectively, are investigated. This paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions. It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications.

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Simulation of the spatio-temporal evolution of the electron energy distribution function in a pulsed hollow-cathode discharge

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Plasma Science and Technology 2023年第3期25卷 87-94页

作者： N A ASHURBEkOV k O ImINOV k m RABADANOV G S SHAkHSINOV m Z ZAkARYAEVA m B kURBANGADZHIEVA Dagestan State University Department of Physics Harbin Institute of Technology Institute of Physics Dagestan Federal Research CenterRussian Academy of Sciences

This article presents the 2D simulation results of a nanosecond pulsed hollow cathode discharge obtained through a combination of fluid and kinetic *** spatio-temporal evolution of the electron energy distribution function(EEDF)of the plasma column and electrical characteristics of the nanosecond pulsed hollow cathode discharge at a gas pressure of 5 Torr are *** results show that the discharge development starts with the formation of an ionization front at the anode *** ionization front splits into two parts in the cathode cavity while propagating along its lateral *** ionization front formation leads to an increase in the fast isotropic EEDF component at its front,as well as in the anisotropic EEDF *** accelerated electrons enter the cathode cavity,which significantly contributes to the formation of the highenergy EEDF component and EEDF anisotropy.

关键词： pulsed nanosecond discharge electron energy distribution fuinction hollow cathode electron kinetics gas discharge