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Growth of Ni Films Observed by Scanning Tunneling Microscopy and X-ray

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Chinese Physics Letters 1999年第5期16卷 370-372页

作者： WANG de-liang u.Geyer National Laboratory for Superconductivity Institute of PhysicsChinese Academy of SciencesBeijing 100080 I.Physikalisches Institut der universitaet Goettingen Bunsenstrasse 9D-37073 GoettingenGermany

Scanning tunneling microscopy was used to measure the mean lateral dimensions D of grains at the surface of Ni films with thicknesses ranging from 15 to *** same films were analyzed by x-ray diffraction to obtain the average linear dimensionsδof coherent scattering regions in the direction normal to the film plane(coherence depths).For thin Ni films condensed on single sapphire substrate at room temperature,these two lengths D andδare equal and increase with film *** for films thicker than 130nm,these two lengths have different constant values and D>δ.This is because the coherent scattering depth is not only limited by the grain sizes but also by various defects in the *** difference between the constant values of D andδdisappears for films after annealing for 30min at 423k in the ultra-high vacuum system.

关键词： dimensions coherent film

A　Study　in　Search　of　Interconnection　between　Surface　Parameters　and　Surrounding　Synoptic　And　Subsynoptic　Features

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Advances in Atmospheric Sciences 1995年第4期12卷 475-486页

作者： R. Pradhan u. k. de P. k. Sen Atmospheric Science Research Group Department of Physics Jadavpur University Calcutta India department of Mathematics Jadavpur University Calcutta India

The paper reveals that the variations in parameters like u *, the scaling velocity and θ*. The scaling temperature during the various phases of monsoon might be linked with subsynoptic features. The rise in u * is mainly connected with the presence of lower tropospheric cyclonic vorticity over a subsynoptic scale of the site. However the variations in θ. is mainly linked with the various phases of monsoon and θ * shows a sharp rise in presence of low level convective *** the correlation studies of u and u., θv and θv, θv-θv0 and θv, * are undertaken. The correlation between θv and θv * is poor. In other two cases correlations are good. Besides u / u * has shown good coefficient of variation values within the ξ range.

关键词： Scaling velocity Scaling temperature Subsynoptic feature Correlation coefficient Coefficient of variation

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

Pressure and Spectral density of Fermions at Finite Temperature

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Chinese Physics Letters 1999年第10期16卷 709-711页

作者： HOu de-fu u.Heinz LI Jia-rong Institute of Particle Physics Huazhong Normal UniversityWuhan 430079 Institut fur Theoretische Physik Universitat RegensburgD-93040 RegensburgGermany

The pressure of a fermion system is expressed as a mass integral over the full two-point spectral densities within the real time formalism by use of the keldysh representation for the *** simpliSes the calculation significantly and allows a Dyson *** expression is used to demonstrate that potential infrared divergences are rendered *** apply it to check the pressures of an ideal fermion gas and of a chemically non-equilibrated quantum chromodynamics plasma.

关键词： Fermi apply render

Synthesis of Nano-sized Barium Titanate Powder by Solid-state Reaction between Barium Carbonate and Titania

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Journal of Materials Science & Technology 2007年第5期23卷 655-658页

作者： u.Manzoor D.k.kim department of Physics COMSATS Institute of Information TechnologyIslamabadPakistan department of Materials Science and Engineering Korea Advanced Institute of Science and Technology(KAIST)DaejeonKorea

Size control of BaTiO3 in solid-state reaction between BaCO3 and TiO2 was demonstrated by varying the size of TiO2 and milling conditions of BaCO3. The smaller TiO2 particles had higher surface area, resulting in faster initial reaction. The mechanically milled BaCO3 particles accelerated the diffusion process and decreased the calcinations temperature. It can be deduced from the results that the size control is possible and nano-sized BaTiO3 particles with about 60 nm can be synthesized by using the conventional solid-state reaction between BaCO3 and TiO2.

关键词： Barium tltanate Mechanical milling Solid-state reaction Nano particles

Saddle Point Criteria in Nonsmooth Semi-Infinite Minimax Fractional Programming Problems

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Journal of Systems Science & Complexity 2018年第2期31卷 446-462页

作者： MISHRA S k SINGH Yadvendra VERMA R u department of Mathematics Banaras Hindu University Varanasi-221005 India. department of Mathematics Texas State University USA

This paper considers a nonsmooth semi-infinite minimax fractional programming problem（SIMFP） involving locally Lipschitz invex functions. The authors establish necessary optimality conditions for SIMFP. The authors establish the relationship between an optimal solution of SIMFP and saddle point of scalar Lagrange function for SIMFP. Further, the authors study saddle point criteria of a vector Lagrange function defined for SIMFP.

关键词： Generalized convexity Lagrange function nonsmooth programming problems saddlepoint semi-infinite minimax fractional programming problems.

Hybrid Active Contour Mammographic Mass Segmentation and Classification

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Computer Systems Science & Engineering 2022年第3期40卷 823-834页

作者： k.Yuvaraj u.S.Ragupathy department of Electronics and Instrumentation Engineering Kongu Engineering College PerunduraiErode638060India

This research implements a novel segmentation of mammographic *** methods are proposed,namely,segmentation of mass based on iterative active contour,automatic region growing,and fully automatic mask selectionbased active contour *** the first method,iterative threshold is performed for manual cropped preprocessed image,and active contour is applied *** overcome manual cropping in the second method,an automatic seed selection followed by region growing is *** that the result is only a few images owing to over segmentation,the third method uses a fully automatic active *** of the segmentation techniques are compared with the manual markup by experts,specifically by taking the difference in their mean ***,the difference in the mean value of the third method is 1.0853,which indicates the closeness of the ***,the proposed method is compared with the existing fuzzy C means and level set *** automatic mass segmentation based on active contour technique results in segmentation with high *** using adaptive neuro fuzzy inference system,classification is done and results in a sensitivity of 94.73%,accuracy of 93.93%,and Mathew’s correlation coefficient(MCC)of 0.876.

关键词： Feature optimization hybrid active contour segmentation mass classification mass feature extraction medical image analysis

Thermal Properties of Ni–Cr–Si–B–Fe Based Interlayer Material and Its Application in TLP Bonding of IN 718 Superalloy

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Acta Metallurgica Sinica(English Letters) 2020年第12期33卷 1666-1680页

作者： u.k.Tarai P.S.Robi Sukhomay Pal department of Mechanical Engineering IIT GuwahatiGuwahati 781039India

A new Ni–Cr–Si–B–Fe fi ller material is prepared for transient liquid-phase(TLP)bonding of Inconel 718 superalloy by mechanical alloying *** melting temperature range of the fi ller material and its activation energy of melting are determined by diff erential scanning calorimetry *** activation energy and melting temperature of the alloy powder decrease with increasing milling *** 718 alloy was joined via TLP by using the newly developed fi ller *** eff ect of TLP bonding temperature and time on microstructural evolution and mechanical properties of the joint was *** distinct microstructural regions were observed in the bonding area:isothermal solidifi cation zone consisting of a single-phase solid solution,diff usion aff ected zone consisting of extensive diff usion-induced precipitates of metallic boride,and unaff ected base *** ultimate shear strength and microhardness of the TLP-bonded joint increase with bonding time and temperature.

关键词： Transient liquid-phase(TLP)bonding kissinger plot Mechanical alloying Inconel 718

Effect of Ipomea carnea Jacq. flowers on hematological changes in toluene diisocyanate-induced inflammation in Wistar rats

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Chinese Journal of Natural Medicines 2014年第3期12卷 161-166页

作者： Jain Smita Patil u.k. department of Pharmacognosy VNS Institute of Pharmacy department of Pharmaceutical Sciences Dr. H.S. Gour Central University

AIM： To investigate the active chloroform fraction of the ethanol extract oflpomoea carnea flowers on hematological changes in toluene diisocyanate-induced inflammation in Wistar rats. METHOD： Except for the control group, all of the rats were sensitized with intranasal application of 5 μL of 10% toluene diiso- cyanate （TDI） for 7 days. One week after second sensitization, all of the rats were provoked with 5 ~tL of 5% TDI to induce airway hypersensitivity. After the last challenge, blood and bronchoalvelor lavage （BAL） fluid were collected and subjected to total and differential leucocytes count. Flash chromatography was performed on the most active chloroform fraction to isolate an individual component. RESuLTS： Treatment with the ethanolic extract and its chloroform fraction at an oral dose of 200 mg·kg^ -1 showed a significant decrease in circulating neutrophil and eosinophil in blood and BAL as compared with standard dexamethasone （deXA）. The structure of the compound obtained from chloroform fraction oflpomea carnea was elucidated as stigmast-5, 22-dien-3β-ol on the basis of spectral data analysis. CONCLuSION： The chloroform fraction was found to be more effective to suppress airway hyper reactivity symptoms, and de- creased count of both total and differential inflammatory cells.

关键词： Ipomea carnea Toluene diisocyanate Bronchoalvelor lavage Neutrophils Stigmasterol