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methanol conversion to DmE as a blue fuel：The beneficial use of ultrasonic irradiation for the preparation of CuO/H-mOR nanocatalyst

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燃料化学学报 2014年第11期42卷 1340-1350页

作者： Sameh m.k. Aboul-Fotouh Ain Shams University Faculty of Education Chemistry Department Roxy Cairo 11566 Egypt

methanol conversion to DmE was investigated over CuO /H-mOR nanocatalyst prepared by precipitation and /or by precipitation flowed by ultrasonic irradiation methods. BET,XRD,SEm,NH3-TPD and H2-TPR techniques were used to characterize nanocatalysts. The effective ultrasonication factors encountered during carrying out the dehydration of methanol on Cuo /H-mOR zeolite catalysts to produce dimethylether are studied in the present work. These factors include: the type of ultrasonication media,the ultrasonication time,and the fixed weight of the solid catalyst per the volume of the ultrasonication liquid media( Wcatalyst/ Vliquidratio). XRD showed that structure of H-mOR is not damaged even after it is loaded with CuO nanoparticles or with ultrasonication. H2-TPR profiles indicated that reducibility of sonicated CuO / H-mOR nanocatalyst is higher than non-sonicated catalyst. It is found that employing ultrasound energy for 60 min has the highest influence on the surface properties of nanocatalyst and its catalytic performance( activity and stability) of CuO / H-mOR catalyst. Surface morphology( SEm) of the sonicated CuO /H-mOR catalysts have clarified that methanol by itself used as an ultrasonication medium gives the best results concerning the homogeneity of particle sizes compared to the non-sonicated catalyst,where large agglomerates and non-homogeneous clusters appeared. Water used as a sonication medium showed many large agglomerates in addition to some smaller particles resulted in lowcatalytic activity. The different alcohols and( Wcatalyst/ Vliquid) ratio were examined to give precise correlation with the catalytic activity of the sonicated CuO / H-mOR zeolite catalyst. These findings certified that ultrasonication has a deep effect on the surface morphology and hence on the catalytic behavior of the dehydration of methanol to DmE. NH3-TPD shows that ultrasound irradiation has enhanced the acidity of CuO / H-mOR catalyst and hence it's catalytic performance for

关键词：燃料化学催化原理催化反应

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Correction of failure in antenna array using matrix pencil technique

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Chinese Physics B 2017年第6期26卷 491-498页

作者： S U khan m k A Rahim Advanced RF & microwave Research Group Department of Communication Engineering Faculty of Electrical Engineering Universiti Teknologi Malaysia 81310 Skudai Johor Malaysia

In this paper a non-iterative technique is developed for the correction of faulty antenna array based on matrix pencil technique（mPT）. The failure of a sensor in antenna array can damage the radiation power pattern in terms of sidelobes level and nulls. In the developed technique, the radiation pattern of the array is sampled to form discrete power pattern information set. Then this information set can be arranged in the form of Hankel matrix（Hm） and execute the singular value decomposition（SVD）. By removing nonprincipal values, we obtain an optimum lower rank estimation of Hm. This lower rank matrix corresponds to the corrected pattern. Then the proposed technique is employed to recover the weight excitation and position allocations from the estimated matrix. Numerical simulations confirm the efficiency of the proposed technique, which is compared with the available techniques in terms of sidelobes level and nulls.

关键词： array correction low rank estimation matrix pencil technique singular value decomposition

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Effect of (Ba_(0.6)Sr_(0.4))TiO_3(BST) Doping on Dielectric Properties of CaCu_3Ti_4O_(12)(CCTO)

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Journal of materials Science & Technology 2012年第12期28卷 1137-1144页

作者： I. Norezan A.k. Yahya m.k. Talari Faculty of Applied Sciences Universiti Teknologi MARAShah Alam Selangor Malaysia

The effect of （Ba（0.6）Sr（0.4））TiO3（BST） addition on dielectric properties of CaCu3Ti4O（12）（CCTO） ceramic was investigated. Ceramic samples with the chemical formula （1-x）CaCu3Ti4O（12）＋ x（Ba（0.6）,Sr（0.4））TiO3 （x=0, 0.05, 0.1, and 0.2） were synthesized from high purity oxide powders by the conventional solid-state synthesis method. X-ray diffraction （XRD） analysis showed the existence of BST as a secondary phase alongside CCTO. Scanning electron microscopy （SEm） investigation showed a slight decrease in grain size of doped CCTO samples. Density measurements showed that porosity content increased with increasing BST addition indicating low densification due to high melting point secondary phase addition. Dielectric constant of undoped CCTO （x=0） showed lack of stability with frequency which dropped drastically between 104 and 105Hz and accompanied by high dielectric loss. Addition of BST into CCTO caused the dielectric constant to slightly decrease but improved stability with frequency compared to the undoped sample. The decrease in dielectric constant of doped CCTO samples was suggested to be partly due to the decrease in average grain size and increase in porosity with BST addition. Nevertheless, a high value of dielectric constant was still maintained around ～104 range for all doped samples. The dielectric loss （tanδ） of all BST-doped samples was lower than that of pure CCTO sample at the frequency range of 103 to 105 Hz probably due to the increase of grains boundary resistivity. The activation energy of grains boundary （E（gb）） showed higher values as compared to the activation energy of grains （Eg ） for all samples and conforms to the internal barrier layer capacitor （IBLC） model.

关键词： CaCu3Ti4O(12)(CCTO) Dielectric properties (Ba(0.6)Sr(0.4))TiO3(BST)

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Corrosion and wear resistance of coatings produced on AZ31 mg alloy by plasma electrolytic oxidation in silicate-based k2TiF6 containing solution:Effect of waveform

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Journal of magnesium and Alloys 2022年第9期10卷 2574-2587页

作者： maryam Rahmati keyvan Raeissi mohammad Reza Toroghinejad Amin Hakimizad monica Santamaria Department of materials Engineering Isfahan University of TechnologyIsfahan 84156-83111Iran Yekta mobaddel Pars Co. Science and Technology CampusYazd UniversityYazd 89158-18411Iran Dipartimento di Ingegneria Università di PalermoViale Delle ScienzeEd.690128PalermoItaly

In this research,plasma electrolytic oxidation coatings were prepared on AZ31 mg alloy in a silicate-based solution containing k_(2)TiF_(6) using bipolar and soft sparking waveforms with 10,20,and 30%cathodic duty *** coatings displayed a net-like surface morphology consisted of irregular micro-pores,micro-cracks,fused oxide particles,and a sintered *** to the incorporation of TiO_(2) colloidal particles and the cathodic pulse repair effect,most of the micro-pores were ***-term corrosion performance of the coatings was investigated using electrochemical impedance spectroscopy during immersion in 3.5 wt.%NaCl solution up to 14 *** coating grown by the soft sparking waveform with a 20%cathodic duty cycle having the lowest porosity(6.2%)and a sharp layer concentrated in F element at the substrate/coating interface shows the highest corrosion *** friction coefficient of this coating has remained stable during the sliding even under 5 N normal load,showing relatively higher wear resistance than other *** coating produced using the equivalent unipolar waveform,as the reference specimen,showed the highest friction coefficient and the lowest wear resistance despite its highest micro-hardness.

关键词： Plasma electrolytic oxidation Pulsed waveforms AZ31 mg alloy Dipotassium titanium hexafluoride Corrosion resistance Wear resistance

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Cell-type specificity of β-actin expression and its clinicopathological correlation in gastric adenocarcinoma

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World Journal of Gastroenterology 2014年第34期20卷 12202-12211页

作者： Shafqat A khan monica Tyagi Ajit k Sharma Savio G Barreto Bhawna Sirohi mukta Ramadwar Shailesh V Shrikhande Sanjay Gupta Epigenetics and Chromatin Biology Group Cancer Research InstituteAdvanced Centre for Treatment Research and Education in CancerTata Memorial CentreKhargharNavi MumbaiMH 410210India Gastrointestinal and Hepato-Pancreato-Biliary Service Department of Surgical OncologyTata Memorial HospitalTata Memorial CentreMumbaiMH 400012India medanta Institute of Hepatobiliary and Digestive Sciences MedantaThe MedicityGurgaonHaryana 122001India medical Oncology-GI and Breast Unit Tata Memorial HospitalTata Memorial CentreMumbaiMH 400012India Department of Pathology Tata Memorial HospitalTata Memorial CentreMumbaiMH 400012India

AIm: To investigate cell type specific distribution of β-actin expression in gastric adenocarcinoma and its correlation with clinicopathological parameters.

关键词： Gastric cancer β-actin Immunohistochemistry Epithelial cells Inflammatory cells Tumor infiltrating immune cells Adjacent mucosa Resection margin

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magnetic, Dielectric and Complex Impedance Properties of xBa_(0.95)Sr_(0.05)TiO_3–(1-x)BiFe_(0.9)Gd_(0.1)O_3multiferroic Ceramics

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Acta metallurgica Sinica(English Letters) 2016年第6期29卷 505-517页

作者： m.J.miah A.k.m.Akther Hossain Department of Physics Bangladesh University of Engineering and Technology Department of Physics Comilla University

xBa_（0.95）Sr_（0.05）TiO_3–（1-x）BiFe_（0.9）Gd_（0.1）O_3[x BST–（1-x）BFGO]（x = 0.00, 0.10, 0.20 and 0.25） multiferroic ceramics were prepared by the standard solid-state reaction technique. Structural characterization was performed by X-ray diffraction. All the samples showed rhombohedral distorted perovskite structure. Surface morphology of the ceramics was studied by the field emission scanning electron microscope（FESEm）. From the FESEm observation, the grain size was observed to be decreased with increasing BST content. Enhanced magnetic properties were observed in BFGO with the increase in BST content because of large lattice distortion. The complex initial permeability increased with the increasing of BST content. The study of dielectric properties showed that the dielectric constant increased, whereas dielectric loss decreased with increasing of BST content due to the reduction of oxygen vacancies. An analysis of the electric impedance and modulus with frequency was performed at different temperatures. Non-Debye-type relaxation processes occur in the compound which was confirmed from the nature of the Cole–Cole plot. The DC conductivity was found to increase with the rise in temperature which indicates the semiconducting behavior of the compound with characteristics of the negative temperature coefficient of resistance. The activation energy, responsible for the relaxation determined from the modulus spectra（0.246 eV）, was found to be almost same as the value obtained from the impedance study（0.240 eV）, indicating that charge carriers overcome the same energy barrier during relaxation. The frequency response of imaginary parts of electric impedance and modulus suggested that the relaxation in xB ST–（1-x）BFGO ceramics follows the same mechanism at various temperatures.

关键词： magnetic properties Dielectric properties Impedance spectroscopy Activation energy

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Role of Ag microalloying on glass forming ability and crystallization kinetics of ZrCoAgAlNi amorphous alloy

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Chinese Physics B 2021年第1期30卷 471-476页

作者： A Surendar k Geetha C Rajan m Alaazim Department of Pharmacology Saveetha Dental College and HospitalSaveetha Institute of Medical and Technical SciencesChennaiIndia CSE Excel Engineering CollegePallakapalayamKomarapalayam637303India IT K S Rangasamy College of Technology TiruchengodeNamakkalTamil Nadu 637215India Faculty of Engineering Universitas Muhammadiyah Surakarta(UMS)Indonesia

Bulk metallic glasses(BmGs) with new chemical compositions(ZrCoAgAlNi) were fabricated and the effects of Ag minor addition on the glass forming ability(GFA) and crystallization kinetics were studied. The x-ray diffraction(XRD) test was applied to identify the amorphousness of BmGs or possible crystalline phases. Using differential scanning calorimeter(DSC), the thermal stability and crystallization kinetics under a non-isothermal condition at the different heating rates were studied. Considering the heating rate dependency of glass transition and crystallization kinetics, the activation energy was evaluated and measured for the mentioned processes. It was revealed that the rise in Ag content led to the decrease in activation energy for glass transition, while the activation energy for crystallization increased. The thermal stability and GFA were also studied and it was found that the Ag addition strongly affected the inherent features of BmGs. With the increase in Ag content, the atomic mobility and structural rearrangement changed in the material and consequently, the GFA and thermal stability were significantly improved.

关键词： bulk metallic glass materials design crystallization kinetics glass forming ability

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Algebraic and group treatments to nonlinear displaced number states and their nonclassicality features:A new approach

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Chinese Physics B 2015年第6期24卷 334-340页

作者： N Asili Firouzabadi m k Tavassoly m J Faghihi Atomic and molecular Group Faculty of PhysicsYazd University The Laboratory of Quantum Information Processing Yazd University Physics and Photonics Department Graduate University of Advanced Technology

Recently, nonlinear displaced number states （NDNSs） have been manually introduced, in which the deformation function f（n） has been artificially added to the previously well-known displaced number states （DNSs）. Indeed, just a simple comparison has been performed between the standard coherent state and nonlinear coherent state for the formation of NDNSs. In the present paper, after expressing enough physical motivation of our procedure, four distinct classes of NDNSs are presented by applying algebraic and group treatments. To achieve this purpose, by considering the DNSs and recalling the nonlinear coherent states formalism, the NDNSs are logically defined through an algebraic consideration. In addition, by using a particular class of Gilmore-Perelomov-type of SU（1,1） and a class of SU（2） coherent states, the NDNSs are introduced via group-theoretical approach. Then, in order to examine the nonclassical behavior of these states, sub-Poissonian statistics by evaluating mandel parameter and Wigner quasi-probability distribution function associated with the obtained NDNSs are discussed, in detail.

关键词： displaced number state nonlinear coherent state Wigner function nonclassical state

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modelling two-layer nanofluid flow in a micro-channel with electro-osmotic effects by means of Buongiorno’s model

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Applied mathematics and mechanics(English Edition) 2020年第1期41卷 83-104页

作者： m.D.k.NIAZI Hang XU State key Lab of Ocean Engineering Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration (CISSE)School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong University

A fully developed steady immiscible flow of nanofluid in a two-layer microchannel is studied in the presence of electro-kinetic ***’s model is employed for describing the behavior of *** from the previous studies on two-layer channel flow of a nanofluid,the present paper introduces the flux conservation conditions for the nanoparticle volume fraction field,which makes this work new and unique,and it is in coincidence with practical *** governing equations are reduced into a group of ordinary differential equations via appropriate similarity *** highly accurate analytical approximations are *** physical quantities and total entropy generation are analyzed and discussed.A comparison is made to determine the significance of electrical double layer(EDL)effects in the presence of an external electric *** is found that the Brownian diffusion,the thermophoresis diffusion,and the viscosity have significant effects on altering the flow behaviors.

关键词： electrical double layer(EDL) entropy generation micro-channel nanofluid

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Structural,Dielectric and Complex Impedance Spectroscopy Studies of Lead Free Ca_(0.5+x)Nd_(0.5-x)(Ti_(0.5)Fe_(0.5))O_3

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Journal of materials Science & Technology 2013年第4期29卷 323-329页

作者： m.R.Shah A.k.m.Akther Hossain Department of Physics University of PrimeasiaBananiDhaka 1213Bangladesh Department of Physics Bangladesh University of Engineering and TechnologyDhaka 1000Bangladesh

Structural and various electrical properties of polycrystalline Ca0.5＋xNd0,5-x（Ti0.5Fe0.5）O3, prepared by standard solid state reaction technique, were studied. Formation of single phase orthorhombic structure of the compositions was confirmed by X-ray diffraction study. The composition dependence of lattice parameters, density and microstructural study show that they vary significantly with Ca content. The dielectric measurements were carried out at room temperature as function of frequency and composition. The experimental results reveal that the dielectric constant （ε′） increases with increasing Ca content. Similar behavior is observed for the dielectric loss （tanδ） and ac conductivity （σac）. In complex impedance analysis it is observed that the real part （Z′） vs imaginary part （Z″） graph exhibits a tendency of formation of a single semicircular arc for each composition of samples. Different parameters were determined by fitting the experimental data in Cole-Cole empirical formula. A dominance of grain boundary resistance （Rgb） is observed. The Rgb decreases with increasing Ca content. The high ε′ observed in present samples are suitable for fabrication of devices.

关键词： Crystal structure Dielectric properties Lead free Perovskite Solid state reaction

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