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The band structures of some transition metals and their Nacl-type compounds

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chinese Journal of chemistry 1996年第5期14卷 385-392页

作者： cai, sh Liu, cW cHINESE AcAD ScI FUJIAN INST RES STRUCT MATTERSTATE KEY LAB STRUCT CHEMFUZHOU 350002FUJIANPEOPLES R CHINA

The band structures of Group IVB (Ti, Zr, Hf), VB (V, Nb, Ta) and VIE (cr, Mo, W) transition metals and some of their carbides and nitrides (TiN, ZrN, HfN, Vc, Nbc, Tac, VN, NbN, TaN) with Nacl-type (B1-type) structure have been calculated by using the tight-binding method within the Extended Huckel approximation (EHT). The energy bands, densities of states and crystal orbital overlap populations are given. The relationship between the bonding properties and the superconducting transition temperatures (T-c) of them is discussed. The influences of various kinds of metallic atoms and changes of bond lengths on T-c are also discussed.

关键词： transition metals and their Nacl-type compounds tight-binding energy band calculation superconducting transition temperatures

Essential commutant of analytic Toeplitz operators

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chinese Science Bulletin 1997年第7期42卷 548-552页

作者： Ding, XH Sun, sh Department of Mathematics Sichuan Union University Chengdu China

LET Bn be the unit ball of cn. The n-dimensional vector space over the complex field c, Sn=（?）Bn is the boundary of Bn. We use σ to denote the unique rotation-invariant probability measure on Sn. The Lebesgue space... 详细信息

关键词： Toeplitz operators inner function essential commutant.

PREPARATION OF cr-POLYSTYRENE cOMPLEX BY METALVAPOR SYNTHESIS

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chinese chemical Letters 1996年第7期7卷 679-680页

作者： Wu, sh Zhu, cY Huang, WP NANKAI UNIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA

chromium atom-hexane solution prepared in a metal atom reactor was transferred into a solution containing polystyrene in diethylene glycol dibutyl ether at -78 degrees c, followed by gently warming the mixture to 0 degrees c to react for two hows, yielding a brown-green solid product Ultraviolet-visible and infrared spectra showed that the product was a bi- (eta(6)-arene) chromium complex.

关键词： cr PREPARATION OF cr-POLYSTYRENE cOMPLEX BY METALVAPOR SYNTHESIS

Discontinuous Sturm-Liouville Problems containing Eigenparameter in the Boundary conditions

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Acta Mathematica Sinica,English Series 2006年第5期22卷 1519-1528页

作者： M.KADAKAL O.sh.MUKHTAROV Ondokuz Mayis University Science and Arts Faculty Department of MathematicsKurupelit 55139 Samsun Turkey Gaziosmanpasa University Science and Arts Faculty Department of MathematicsTokat 60000 Turkey

In this paper, discontinuous Sturm-Liouville problems, which contain eigenvalue parameters both in the equation and in one of the boundary conditions, are investigated. By using an operatortheoretic interpretation we extend some classic results for regular Sturm-Liouville problems and obtain asymptotic approximate formulae for eigenvalues and normalized eigenfunctions. We modify some techniques of [Fulton, c. T., Proc. Roy. Soc. Edin. 77 （A）, 293-308 （1977）], [Walter, J., Math. Z., 133, 301-312 （1973）] and [Titchmarsh, E. c., Eigenfunctions Expansion Associated with Second Order Differential Equations I, 2nd edn., Oxford Univ. Pres, London, 1962], then by using these techniques we obtain asymptotic formulae for eigenelement norms and normalized eigenfunctions.

关键词： Sturm-Liouville problem discontinuous boundary-value problem eigenvalue and eigenfunction eigenelement normalized eigenfunctions

corrosion protection and mechanical properties of the electroless Ni-P-MOF nanocomposite coating on AM60B magnesium alloy

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Journal of Magnesium and Alloys 2022年第8期10卷 2280-2295页

作者： Z.Rajabalizadeh D.Seifzadeh A.Khodayari sh.Sohrabnezhad Applied chemistry Department University of Mohaghegh ArdabiliArdabil ***Iran Department of chemistry Faculty of ScienceUniversity of GuilanP.O.Box 1914RashtIran

Al-based MIL-53 MOF nanostructure was synthesized hydrothermally and then co-deposited in the electroless nickel coating on AM60B magnesium alloy using Zr pretreatment as an eco-friendly *** MIL-53(Al)nanostructure was synthesized in the form of layered semi-cube crystals with the surface area and mean pore diameter of 985.72 m^(2)g^(-1) and 2.00 nm,*** SEM images captured with two various zooming scales from the surface of the plain and MOF containing electroless layers showed cauliflower-like morph.logy with even distribution of nodule ***,the sub-grains of the plain coating disappeared after incorporation of the ***,both the normal and nanostructure-containing electroless layers have crystalline-amorph.us structure,but the nanocomposite coating showed less *** average surface roughness of the plain electroless coating was about 309 nm,which decreased to about 222 nm after incorporation of the *** XRD patterns showed that the characteristic peak of Ni broadened after incorporation of the MOF,probably due to the decreasing of the *** the heat-treated normal and MOF containing coatings at 200℃ no ph.se transition takes place,but new peaks appeared for heat-treated coatings at 400℃ due to the crystallization and second-ph.se *** results of the EIS tests showed an increase in the amount of the charge transfer resistance(from 19 to 29 kΩcm^(2))after addition of the MOF,which means an improvement in the corrosion ***,low Jcorrof the composite coating represents its higher corrosion resistance with respect to the plain *** micro-hardness values of the composite coating before and after the heat treatment were higher than the plain ***,the Ni-P-MOF coating has a lower wear rate both before and after the heat treatment due to an improvement in its micro-hardness.

关键词： Electroless plating MOF Magnesium alloy Wear EIS

Nanoscale potential barrier distributions and their effect on current transport in Ni/n type Si Schottky diode

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Journal of Semiconductors 2015年第12期36卷 74-80页

作者： M.Yeganeh N.Balkanian sh.Rahmatallahpur West North Research complex

We have experimentally studied the Ni/n-Si nano Schottky barrier height （SBH） and potential difference between patches in the nano Schottky diodes （SD） using contact atomic force microscopy （c-AFM） in tapping mode and scanning tunneling microscopy （STM）. Topology measurement of the surface with c-AFM showed that, a single Ni/n-Si SD consists of many patches with different sizes. These patches are sets of parallel diodes and electrically interacting contacts of 5 to 50 nm sizes and between these individual diodes, there exists an additional electric field. In real metal semiconductor contacts （MSc）, patches with quite different configurations, various geometrical sizes and local work functions were randomly distributed on the surface of the metal. The direction and intensity of the additional electric field are distributed in homogenously along the contact metal surface. SBH controls the electronic transport across the MS interface and therefore, is of vital importance to the successful operation of semiconductor devices.

关键词： nano Schottky diode additional electrical field nanopatch STM and c-AFM

Structure of A=11 double-Λ hypernuclei studied with three-body forces

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chinese ph.sics c 2013年第5期37卷 22-27页

作者： H. Sadeghi sh. Nahidinejad K. Bahraminejad Department of ph.sics Faculty of Science Arak University

The energy levels and AA bond energy of the double-A hypernucleus nBe are calculated considering two- and three-nucleon forces. The interactions between the constituent particles are contact interactions that reproduce the low-energy binding energy of the nuclei. Effective action is constructed to involve the three-body forces. In this paper, we compare the binding energy result that is obtained with the experimental and other modern nucleon- nucleon potentials. The results of all the schemes agree very well, showing the high accuracy of our present ability to calculate the many-nucleon bound state with three-body forces. The experimental value of BAA（Be）=20.83 MeV seems to be more compatible with our calculated value of BAA（Be）=-19.31 MeV in comparison with the calculated result of 18.23 MeV by Hiyama et al.

关键词： five-body cluster A=11 double-A hypernuclei binding energy three-body forces

Estimation of wind speeds inside Super Typh.on Nepartak from AMSR2 low-frequency brightness temperatures

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Frontiers of Earth Science 2019年第1期13卷 124-131页

作者： Lei ZHANG Xiaobin YIN Hanqing sh Zhenzhan WANG Qing XU Institute of Meteorology and Oceanograph. National University of Defense TechnologyNanjing 211101China Beijing Piesat Information Technology co.Ltd Beijing 100195China National Space Science center Chinese Academy of SciencesBeijing 100190China college of Oceanograph. Hohai UniversityNanjing 211101China

Accurate estimations of typh.on-level winds are highly desired over the westem Pacific Ocean.A wind speed retrieval algorithm is used to retrieve the wind speeds within Super Typh.on Nepartak (2016)using 6.9- and 10.7-GHz brightness temperatures from the Japanese Advanced Microwave Scanning Radiometer 2 (AMSR2) sensor on board the Global change Observation Mission-Water 1 (GcOM-Wl)*** results show that the retrieved wind speeds clearly represent the intensification process of Super Typh.on Nepartak.A good agreement is found between the retrieved wind speeds and the Soil Moisture Active Passive wind speed *** mean bias is 0.51 m/s,and the root-mean-square difference is 1.93 m/s between *** retrieved maximum wind speeds are 59.6 m/s at 04:45 UTc on July 6 and 71.3 m/s at 16:58 UTc on July *** two results demonstrate good agreement with the results reported by the china Meteorological Administration and the Joint Typh.on Warning *** addition,Feng-Yun 2G (FY-2G) satellite infrared images,Feng-Yun 3c (FY-3c)microwave atmosph.ric sounder data,and AMSR2 brightness temperature images are also used to describe the development and structure of Super Typh.on Nepartak.

关键词： microwave radiometer sea surface wind retrieval AMSR2 Nepartak SMAP

Synthesis of Wc powder through microwave heating of WO_3–c mixture

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International Journal of Minerals,Metallurgy and Materials 2017年第2期24卷 202-207页

作者： Amir Karimzadeh Behnami Arman Hoseinpur Masoud Sakaki Mohammad sh. Bafghi Kazumichi Yanagisawa School of Metallurgy and Materials Engineering Iran University of Science and Technology (IUST) Narmak Tehran 16846-13114 Iran Department of Materials Engineering Faculty of Engineering Malayer University Malayer 65719-95863 Iran Research Laboratory of Hydrothermal chemistry Faculty of Science Kochi University Kochi 780-8073 Japan

A simple, easy, and low-cost process for the fabrication of tungsten carbide （Wc） powder through microwave heating of WO3-c mixtures was developed. Thermodynamic calculations and experimental investigations were carried out for WO3-and W-c systems, and a formation mechanism was proposed. In the results, for the synthesis of Wc, the use of over stoichiometric amount of c together with a spe- cially assembled experimental setup （which effectively retains heat in the system） is necessary. The Wc powder is successfully obtained by heating WO3：5c mixture for 900 s in a domestic microwave oven.

关键词： tungsten carbide microwave heating carbothermic reduction thermodynamic analysis