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Chinese Physics B 2010年第10期19卷 477-484页

作者： M. A. Yeganeh sh. rahmatallahpur A. Nozad r. k. Mamedov Faculty of Physics Baku State University Academic Zahid Xlilov Küsi-23 AZ 1148 Iran Material research School POB 55515196 Binab Iran

Small high-quality Au/n type-GaAs Schottky barrier diodes （SBDs） with low reverse leakage current are produced using lithography. Their effective barrier heights （BHs） and ideality factors from current-voltage （I-V） characteristics are measured by a Pico ampere meter and home-built I-V instrument. In spite of the identical preparation of the diodes there is a diode-to-diode variation in ideality factor and barrier height parameters. Measurement of topology of a surface of a thin metal film with atomic force microscope （AFM） shows that Au-n type-GaAS SD consists of a set of parallel-connected micro and nanocontacts diodes with sizes approximately in a range of 100-200 nm. Between barrier height and ideality factor there is an inversely proportional dependency. With the diameter of contact increasing from 5 μm up to 200 μm, the barrier height increases from 0.833 up to 0.933 eV and its ideality factor decreases from 1.11 down to 1.006. These dependencies show the reduction of the contribution of the peripheral current with the diameter of contact increasing. We find the effect of series resistance on barrier height and ideality factor.

关键词： Schottky barrier diodes conducting probe-atomic force microscope barrier height andideality factor

Effect of porosity on active damping of geometrically nonlinear vibrations of a functionally graded magneto-electro-elastic plate

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Defence Technology（防务技术） 2022年第6期18卷 891-906页

作者： L.sh Esayas Subhaschandra kattimani Department of Mechanical Engineering National Institute of Technology KarnatakaSurathkal575025India

This paper investigates the effect of porosity on active damping of geometrically nonlinear vibrations(GNLV)of the magneto-electro-elastic(MEE)functionally graded(FG)plates incorporated with active treatment constricted layer damping(ATCLD)*** perpendicularly/slanted reinforced 1-3 piezoelectric composite(1-3 PZC)constricting *** constricted viscoelastic layer of the ATCLD is modeled in the time-domain using Golla-Hughes-Mc Tavish(GHM)*** types of porosity distribution in the porous magneto-electro-elastic functionally graded PMEE-FG plate graded in the thickness *** the coupling effects among elasticity,electrical,and magnetic fields,a three-dimensional finite element(FE)model for the smart PMEE-FG plate is obtained by incorporating the theory of layer-wise shear *** geometric nonlinearity adopts the von k arm an *** study presents the effects of a variant of a power-law index,porosity index,the material gradation,three types of porosity distribution,boundary conditions,and the piezoelectric fiber’s orientation angle on the control of GNLV of the PMEE-FG *** results reveal that the FG substrate layers’porosity significantly impacts the nonlinear behavior and damping performance of the PMEE-FG plates.

关键词： Nonlinear vibration Magneto-electro-elastic(MEE)plates Active treatment constricted layer damping(ATCLD) Porosity distribution Porous functionally graded

Inverse Heat Transfer Problem of Thermal Contact Conductance Estimation in Periodically Contacting Surfaces

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Journal of Thermal Science 2009年第2期18卷 150-159页

作者： M.H.shojaeefard k.Goudarzi M.sh.Mazidi Dept. of Mechanical Engineering Iran University of Science and Technology

The problems involving periodic contacting surfaces have different practical applications. An inverse heat conductionproblem for estimating the periodic Thermal Contact Conductance (TCC) between one-dimensional, constantproperty contacting solids has been investigated with conjugate gradient method (CGM) of function *** method converges very rapidly and is not so sensitive to the measurement errors. The advantage of thepresent method is that no a priori information is needed on the variation of the unknown quantities, since the solutionautomatically determines the functional form over the specified domain. A simple, straight forward techniqueis utilized to solve the direct, sensitivity and adjoint problems, in order to overcome the difficulties associatedwith numerical methods. Two general classes of results, the results obtained by applying inexact simulatedmeasured data and the results obtained by using data taken from an actual experiment are presented. In addition,extrapolation method is applied to obtain actual results. Generally, the present method effectively improves theexact TCC when exact and inexact simulated measurements input to the analysis. Furthermore, the results obtainedwith CGM and the extrapolation results are in agreement and the little deviations can be negligible.

关键词： thermal contact inverse problem conjugates gradient method

PrEDICTION OF STOrM SUrGES IN THE BAY OF BENGAL

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Tropical Cyclone research and review 2012年第1期1卷 51-54页

作者： sh.sh.r k.dube Indian Institute of Technology

The destruction due to storm surge flooding is a serious concern along the coastal regions of the countries around the Bay of Bengal. About 300,000 lives were lost in one of the most severe cyclones that hit Bangladesh(then East Pakistan) in November 1970. More recently the Nargis cyclone of May 2008 killed about 140,000 people in Myanmar as well as caused enormous property damage. Thus, provision of precise prediction and warning of storm surges is of great interest in the region. The main objective of the present paper is to highlight the recent developments in storm surge prediction in the Bay of Bengal and also the future plan to enhance storm surge forecasting capability in the region.

关键词： destruction storm Bengal

Characteristic Assessment of Stabilized Polyacrylonitrile Nanowebs for the Production of Activated Carbon Nano-Sorbents

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Chinese Journal of Polymer Science 2014年第4期32卷 449-457页

作者： S.rafiei B.Noroozi sh.Arbab A.k.Haghi Department of Textile Engineering University of Guilan

Polyacrylonitrile （PAN） nanofibers with average diameter of 300 nm were produced by electro-spinning. The nanofibers were stabilized at different temperatures in the range of 180-270 ℃in several duration times and heating rates. Fourier transforms infrared （FTIr） spectroscopy, differential scanning calorimetry （DSC） and X-ray diffraction （XrD） analyzing techniques were employed to measure the extent of stabilization reaction. By all procedures, the ranges of temperature and duration time recommended were about 250-270 ℃ and 1-2 h, respectively. Increasing the activation temperature from 800 ℃ to 1200 ℃ caused porosity and pore volume development up to 60% and 0.532 cm3/g, respectively. Pore width of all samples was calculated to be about 0.7 nm confirming micro-pore structure of the produced PAN based activated carbon nanofibers. Comparing dye adsorption for different adsorbents including chitin and granular activated carbon （GAC） showed the highest efficiency for the produced activated carbon nanofibers （ACNFs）.

关键词： Polyacrylonitrile Electro-spinning Stabilization Activated carbon nanofibers Adsorbent.

SLOW PELLETING COAGULATION OF POLYMEr LATEX EMULSION

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Chinese Chemical Letters 1996年第3期7卷 297-298页

作者： Li, YM Chen, MW Xu, GJ Ou, sh Wang, k ZHEJIANG UNIV DEPT POLYMER SCI & ENGNHANGZHOU 310027PEOPLES R CHINA

In this paper, slow pelleting flocculation of polymer latex consisting of butadiene, styrene and methyl methacrylate(MBS) were investigated, using aqueous H2SO4 as coagulant. It is found that spherical particles with uniform particle size and high bulk density were produced in the narrow range of pH. In order to obtain good particle morphology, well-distributed concentration, temperature and shear field in the coagulating system were required. Polymer latex made from emulsion polymerization often needs to be converted into dry powders. Usually, we simply add excessive coagulant, such as inorganic acid, salt, etc., into latex emulsion to make it coagulate. The particles formed with such method always have irregular shape and high fines content. In recent years, more attention has been paid to the method of getting coagulated particles with satisfactory particle morphology(1-3)].

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GEOID: GrID Services for Earth Observation Image Data Processing

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International Journal of Digital Earth 2013年第2期6卷 185-195页

作者： Nitant dube r.ramakrishnan k.S.Dasgupta Space Applications Centre ISROAhmedabadIndia Indian Institute of Space Science and Technology ThiruvananthapuramIndia

recent developments in space technology and exponential increase in demand of earth observation data from space have generated a requirement of a data processing environment,where users can discover the data and process,based on their *** Services for Earth Observation Image Data Processing(GEOID)is proposed with a motivation to cater to future earth observation applications requirements of digital *** paper discusses the overview of the GEOID architecture,its deployment scenario,use-cases and simulation *** technologies used for implementation include Grid computing and Service Oriented *** provides capability to address require-ments of applications such as real-time monitoring,time series data processing and processing with user required quality to meet the requirements of end user *** allows users to access the archive products or the raw satellite data stream and process their area of *** show that applications such as time series analysis show considerable improvement in processing time by using GEOID.

关键词： earth observation digital earth GrID GEOID service oriented architecture GridSIM

Lower Bounds for Local Cohomology Modules with respect to a Pair of Ideals

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Algebra Colloquium 2016年第2期23卷 329-334页

作者： M. Lotfi Parsa sh. Payrovi Faculty of Science Sayyed Jamaleddin Asadabadi University Postal code: 65418-3-5583 Asadabad Iran Department of Mathematics Imam Khomeini International University Postal code: 34149-1-6818 Qazvin Iran

Let r be a Noetherian ring, I and J two ideals of r, M an r-module and t an integer. Let S be a Serre subcategory of the category of r-modules satisfying the co ondition CI, and N be a finitely generated r-module with SupprN= V（a） for some a ∈ W（I, J）. It is shown that if Extr^J（N,HI^i,J（M）） ∈ S for all i 〈 t and all j 〈 t - i, then Ha^i（M） ∈ S for all i 〈 t. Let S be the class of all r-modules N with divmr N ≤ k, where k is an integer. It is proved that if Ha^i（M） ∈ S for all i 〈 t and all a ∈ W（I, J）, then HI^i,j（M） ∈ S for all i 〈 t. It follows that inf{i ： HI^i,j（M） S} = inf（inf{i ： Ha^i（M） S）： a ∈W（I,J）}.

关键词： extension functor local cohomology Serre subcategory

The s-Ordered Fock Space Projectors Gained by the General Ordering Theorem

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Chinese Physics Letters 2012年第9期29卷 5-7页

作者： Farid shähandeh Mohammad reza Bazrafkan Mahmoud Ashrafi Department of Physics Faculty of ScienceI.K.I.UniversityQazvinIran

Employing the general ordering theorem(GOT),operational methods and incomplete 2-D Hermite polynomials,we derive the t-ordered expansion of Fock space *** the result,the general ordered form of the coherent state projectors is *** indeed gives a new integration formula regarding incomplete 2-D Hermite *** addition,the orthogonality relation of the incomplete 2-D Hermite polynomials is derived to resolve Dattoli's failure.

关键词： incomplete ordered Fock

Selective Dealumination of ZSM-5 by Hydrothermal Treatment

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Chinese Chemical Letters 1998年第4期9卷 397-400页

作者： Zhang, k Zhang, HB Xiang, sh Liu, SY Li, HX He, F Nankai Univ Dept Chem Catalysis Lab Tianjin 300071 Peoples R China Tianjin Univ State Key Lab C Chem Tianjin 300072 Peoples R China

We studied the factors affecting the framework aluminium distribution in the ZSM-5 structure by hydrothermal treatment under different conditions. (27)AlMASNMr, XPS and chemical analysis revealed that with steaming at lower water vapor pressure, the framework aluminium located at the external surface is less stable. Steaming at higher water vapor pressure is beneficial in removing the framework Al in HZSM-5, and especially helpful in removing that located at the internal surface of HZSM-5. By changing steaming conditions, one may control the framework aluminium distribution in the HZSM-5 structure.

关键词： selective dealumination water vapor pressure steaming HZSM-5