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Optimizing the Preparation Parameters of Nanocrystalline Zirconia for Catalytic Applications

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Acta metallurgica Sinica(English Letters) 2013年第5期26卷 565-573页

作者： m.m.Abd El-Latif m.S.Showman A.m.Ibrahim m.m.Soliman Fabrication Technology Department Advanced Technology and New Materials Research Institute(ATNMRI) City of Scientific Research and Technological Applications (SRTA-City) Dharyya Colleges for Science and Atrs Qassim University Surface Chemistry and Catalysis Laboratory Physical Chemistry Department National Research Center Department of materials Science Institute of Graduate Studies and Research Alexandria University

Nanocrystalline zirconia powder with high surface area and high tetragonal phase percentage is prepared by the precipitation method using ammonium hydroxide as a precipitating agent. The pH of precipitation, preparation temperature and calcinations＇ temperature are *** size, specific surface area, tetragonal phase percentage and the thermal stability of the prepared samples are identified by diferent characterization tools such as X-ray difraction（XRD）, thermo gravimetric analysis（TGA）, diferential scanning calorimetry（DSC）, BET surface area, scanning electron microscopy（SEm） and transmission electron microscopy（TEm）. The optimum preparation parameters for obtaining nanocrystalline zirconia with high percentage of tetragonal phase and high surface area are pH 9, preparation temperature of 80℃ and calcinations＇ temperature of 400℃. The sample prepared under optimized conditions showed a high specific surface area of 179.2 m2/g, high tetragonal phase percentage of 81% and high catalytic activity（60%） for synthesis of butyl acetate ester.

关键词： Tetragonal zirconia Nanocrystalline zirconia Precipitation synthesis Catalytic properties of zirconia Esterification with zirconia

Dissipative dynamics of an entangled three-qubit system via non-Hermitian Hamiltonian: Its correspondence with markovian and non-markovian regimes

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Chinese Physics B 2021年第3期30卷 283-292页

作者： m Rastegarzadeh m K Tavassoly Laser and Optics Group Faculty of PhysicsYazd UniversityYazd 89195-741Iran

We investigate an entangled three-qubit system in which only one of the qubits experiences the decoherence effect by considering a non-Hermitian Hamiltonian,while the other two qubits are isolated,i.e.,do not interact with environment,***,the time evolution of the density matrix(for the pure as well as mixed initial density matrix)and the corresponding reduced density matrices are obtained,by which we are able to utilize the dissipative non-Hermitian Hamiltonian model with markovian and non-markovian regimes via adjusting the strange of the non-Hermitian term of the total Hamiltonian of the under-considered system.

关键词： non-Hermitian Hamiltonian entanglement concurrence measure markovian and non-markovian regimes

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01期 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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Dynamic simulation of beam-like structure with a crack subjected to a random moving mass oscillator

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Earthquake Engineering and Engineering Vibration 2009年第3期8卷 447-458页

作者： m.m.Ettefagh m.H.Sadeghi m.Rezaee Vibration and modal Analysis Laboratory 51666-14766Department of Mechanical EngineeringUniversity of TabrizTabrizIran

In this paper, dynamic simulation of a beam-like structure with a transverse open crack subjected to a random moving mass oscillator is investigated. The simultaneous effect of a crack and a random oscillator has not been addressed up to now. The crack in the beam at different locations and with different depths is considered as one group of damage, each as an individual imperfection. In addition, bearing immobility is considered as another type of problem in the beam. mass, stiffness, damping and velocity of the oscillator are assumed to be random parameters. An improved perturbation technique is applied to reduce the simulation time. It was found that there is a maximum value of the variance of each uncertain parameter, in which the maximum reliability of the perturbation method can be achieved, and that this maximum value can be obtained by the Alpha-Hilber monte-Carlo simulation method. The simulation results reveal that the mass and the velocity uncertainty cause high uncertainty in the deflection of the beam. Also, the pattern of the deflection is not affected by different random oscillator parameters, and as a result, the type of damage can be identified even with high uncertainty. moreover, the deflection in the nodes around the mid-span of the beam provides the best information regarding the imperfections, and consequently leads to the best sensor locations in an actual experiment.

关键词： bridge-vehicle interaction moving mass oscillator random parameters monte-Carlo simulation perturbation method

Cracking in orthotropic half-plane with a functionally graded coating under anti-plane loading

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Acta mechanica Solida Sinica 2015年第2期28卷 210-220页

作者： m. m. monfared m. Ayatollahi Faculty of Engineering University of Zanjan

This investigation evaluates, by the dislocation method, the dynamic stress intensity factors of cracked orthotropic half-plane and functionally graded material coating of a coating- substrate material due to the action of anti-plane traction on the crack surfaces. First, by using the complex Fourier transform, the dislocation problem can be solved and the stress fields are obtained with Cauchy singularity at the location of dislocation. The dislocation solution is utilized to derive integral equations for multiple interacting cracks in the orthotropic half-plane with functionally graded orthotropic coating. Several examples are solved and dynamic stress intensity factors are obtained.

关键词： orthotropic half-plane multiple cracks functionally graded coating

SWELLING BEHAVIOR OF ACRYLAmIDE HYDROGEL IN DIFFERENT SOLVENTS AND pHs

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Chinese Journal of Polymer Science 2005年第3期23卷 269-274页

作者： m.F.mina m.m.Alam Institute of Nuclear Science and Technology Atomic Energy Research EstablishmentGPO Box-3787Dhaka-1000BangladeshInstitute of Nuclear Science and TechnologyAtomic Energy Research EstablishmentGPO Box-3787Dhaka-1000Bangladesh

Swelling property of acrylamide hydrogels,prepared from aqueous solutions of acrylamide monomer havingconcentrations in the range of 10-60 wt% by ray irradiation method using a Co-60 gamma radiation source at dosesranging 1-30.0 kGy,has been investigated under various swelling *** swelling media were basically solvents(solutions),produced by dissolving methanol,ethanol,glucose,sucrose,sodium chloride and sodium persulfate individuallywith distilled water,and solutions prepared with pHs=3,7 and *** investigation was performed in order to observe theeffect of these solvents and pHs as well as the influence of monomer concentrations,radiation doses and times on swellingbehavior of *** values were found higher for hydrogels prepared with lower monomer concentrations(ca.20 wt%)and radiation doses(ca.5 kGy)and showed a leveling off tendency within 24 *** glucose solvent and the buffersolution of pH=10 revealed significant increase of swelling of hydrogels as compared to other *** areexplained based on crosslinking density in hydrogel,polymer-solvent/polymer-polymer interactions in solutions,permeability of molecules in solutions and ionization capacity of hydrogel in pH.

关键词： Acrylamide Hydrogel Co-60 gamma radiation source Swelling.

metabolic surgery and intestinal gene expression:Digestive tract and diabetes evolution considerations

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World Journal of Gastroenterology 2015年第22期21卷 6990-6998页

作者： marcos Ricardo da Silva Rodrigues marco Aurelio Santo Giovani marino Favero Elaine Cristina Vieira Roberto Ferreira artoni Viviane Nogaroto Egberto Gaspar de moura Patricia Lisboa Fabio Quirillo milleo Laboratório multidisciplinar da Universidade Estadual de Ponta Grossa-Campus Uvaranas Avenida General Carlos Cavalcanti

AIm: To investigate the effects of bariatric surgery on metabolic parameters, incretin hormone secretion, and duodenal and ileal mucosal gene ***: Nine patients with type 2 diabetes mellitus(T2Dm), chronic serum hyperglycemia for more than2 years, and a body mass index(BmI) of 30-35 kg/m2 underwent metabolic surgery sleeve gastrectomy with transit bipartition between may 2011 and December2011. Blood samples were collected pre and 3, 6 and12 mo postsurgery. Duodenal and ileal mucosa samples were collected pre- and 3 mo postsurgery. Pre- and postoperative blood samples were collected in the fasting state before ingestion of a standard meal(520kcal) and again 30, 60, 90, and 120 min after the mealto determine hemoglobin A1c(HbA1c) levels and the lipid profile, which consisted of triglyceride and total cholesterol levels. Intestinal gene expression of p53 and transforming growth factor(TGF)-β was analyzed using quantitative reverse-transcription PCR. Gastric inhibitory polypeptide(GIP) and glucagon-like peptide-1(GLP-1)were quantified using the enzyme-linked immunoassay method and analyzed pre- and ***'s t test or repeated measurements analysis of variance with Bonferroni corrections were performed as ***: BmI values decreased by 15.7% within the initial 3 mo after surgery(31.29 ± 0.73 vs 26.398± 0.68, P mo postoperative, resulting in similar values 12 mo postoperatively(20-25 kg/m2). All of the patients experienced improved T2 Dm, with 7 patients(78%)achieving complete remission(HbA1c mproved diabetes(HbA1cmic agents). At 3 mo postoperatively, fasting plasma glucose had also decreased(59%)(269.55 ±18.24 mg/dL vs 100.77 ± 3.13 mg/dL, P mo postoperatively. In the first month postoperatively,there was a complete withdrawal of hypoglycemic medica

关键词： Diabetes mellitus Hyperglycemia Intestine Gene expression Hyperplasia Bariatric surgery

Plasma Treatment of Natural Jute Fibre by RIE 80 plus Plasma Tool

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Plasma Science and Technology 2010年第3期12卷 325-329页

作者： m.m.mORSHED m.m.ALAm S.m.DANIELS National Centre for Plasma Science and Technology Dublin City University Nanomaterials Processing Laboratory School of Electronic EngineeringDublin City University

Plasma treatment can be used to modify the structure of natural fibre like jute for a variety of applications. Environmentally friendly jute fibre was treated with argon and oxygen plasma. The treated samples were characterized by X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR） and optical microscope. The macromolecular and microstructural changes in cellulose confirmed the change by plasma treatment. The XRD results confirmed that the crystal size and the crystallinity of the plasma treated fibre increased. Argon plasma treated fibre had a smooth and compact surface, compared to oxygen plasma treated fibre. The maximum stain （i.e. stress） concentrated in the oxygen plasma treated fibre. Optical micrographs showed the oxygen plasma treated fibre tended to rupture due to higher strain （i.e., stress） compared to fibre with argon plasma treatment. FTIR results also provided the evidence of change in the chemical constituents with plasma treatment.

关键词： natural jute fibre plasma treatment crystallinity chemical composition

Interactions of ion acoustic multi-soliton and rogue wave with Bohm quantum potential in degenerate plasma

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Chinese Physics B 2017年第9期26卷 301-309页

作者： m S Alam m G Hafez m R Talukder m Hossain Ali Department of Applied mathematics University of RajshahiRajshahi-6205Bangladesh Plasma Science and Technology Lab Department of Applied Physics and Electronic EngineeringUniversity of RajshahiRajshahi-6205Bangladesh Department of mathematics Chittagong University of Engineering and TechnologyChittagong-4349Bangladesh

This work investigates the interactions among solitons and their consequences in the production of rogue waves in an unmagnetized plasmas composing non-relativistic as well as relativistic degenerate electrons and positrons, and inertial non-relativistic helium ions. The extended Poincare′–Lighthill–Kuo（PLK） method is employed to derive the two-sided Korteweg–de Vries（KdV） equations with their corresponding phase shifts. The nonlinear Schrodinger equation（NLSE） is obtained from the modified Kd V（mKdV） equation, which allows one to study the properties of the rogue waves. It is found that the Fermi temperature and quantum mechanical effects become pronounced due to the quantum diffraction of electrons and positrons in the plasmas. The densities and temperatures of the helium ions, degenerate electrons and positrons, and quantum parameters strongly modify the electrostatic ion acoustic resonances and their corresponding phase shifts due to the interactions among solitons and produce rogue waves in the plasma.

关键词： wave-wave interaction rogue waves degenerate plasmas Bohm potential