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Magnetic,magetostrictive properties,spin reorientation and Mssbauer effect of Tb_(0.3)Dy_(0.7-x)Prx(Fe_(0.9)Al_(0.1))_(1.95) alloys

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Science china(Physics,Mechanics & Astronomy) 2009年第1期52卷 52-57页

作者： ZHENG XiaoPing1,2, ZHANG PeiFeng2,3, FAN DuoWang3 & LI FaShen3 1 Institute of electronic Information Science and technology, lanzhou City university, lanzhou 730070, china 2 key laboratory of opto-electronic technology and intelligent control, ministry of education, lanzhou jiaotong university, lanzhou 730070, china 3 key laboratory for Magnetism and Magnetic Materials, ministry of education, lanzhou university, lanzhou 730000, china 1. Institute of electronic Information Science and technology Lanzhou City University Lanzhou 730070 China 2. key laboratory of opto-electronic technology and intelligent control Ministry of Education Lanzhou Jiaotong University Lanzhou 730070 China 3. key laboratory for Magnetism and Magnetic Materials Ministry of Education Lanzhou University Lanzhou 730000 China

The effect of Pr substitution for Dy on the magnetic and magnetostrictive properties, anisotropy, spin reorientation and Mssbauer effect of a series of Tb0.3Dy0.7-xPrx(Fe0.9Al0.1)1.95 (x=0,0.1,0.20,0.25,0.30,0.35) alloys at room temperature have been investigated. It was found that a small amount of Pr substitution is beneficial to a decrease in the magnetocrystalline anisotropy for the Tb0.3Dy0.7-xPrx(Fe0.9Al0.1)1.95 alloys. The magnetostriction decreases drastically with increasing x and the magnetostrictive effect disappears for x>0.2. However, the magnetostriction exhibits a slightly bigger value at x=0.1 than the free alloys and is saturated more easily with the magnetic field H. The saturation magnetization and Curie temperature decrease monotonously, but the spontaneous magnetostriction increases linearly with increasing x, whereas the spin reorientation temperature increases first, then decreases rapidly and reaches the maximum at x=0.1. The analysis of Mssbauer spectra indicated that the easy magnetization direction in the {110} plane deviates slightly from the main axis of symmetry with the Pr concentration x, namely spin reorientation. Compared with Al substitution for Fe, the effect of Pr substitution for Dy on spin reorientation is relatively small. The hyperfine field increases with Pr concentration increasing, and the isomer shifts and the quadrupole splitting (QS) show weak concentration dependence.

关键词： magnetostriction anisotropy spin reorientation Mssbauer

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A computer simulation of nucleation and growth of thin films

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Science china(Physics,Mechanics & Astronomy) 2004年第4期47卷 442-451页

作者： ZHENG Xiaoping1,ZHANG Peifeng2,HE Deyan2,LIU Jun2& MA Jiantai3 1. key laboratory of opto-electronic technology and intelligent control, ministry of education, lanzhou jiaotong university, lanzhou 730070, china 2. School of Physical Science and technology, lanzhou university, lanzhou 730000, china 3. School of Chemistry and Chemistry Engineering, lanzhou university, lanzhou 730000, china key laboratory of opto-electronic technology and intelligent control Ministry of Education Lanzhou Jiaotong University Lanzhou China School of Physical Science and technology Lanzhou University Lanzhou China School of Chemistry and Chemistry Engineering Lanzhou University Lanzhou China

A three-dimensional kinetic Monte Carlo technique has been developed for simulating the nucleation and growth of thin films. This model involves incident atom attachment, surface diffusion of the atoms on the growing surface and atom detachment from the growing surface. It takes some new effects into account, such as a significant improvement in calculation of activation energy for the atom diffusion, which renders the model more reasonable. In addition three optimum temperatures and the consistency of their dependence on deposition rate have been found out; the dependence of the surface roughness and relative density on the deposition rate has been discussed; and the approximation of freezing neighbour atoms and periodic boundary conditions has been applied.

关键词： Monte Carlo, thin film, nucleation, surface roughness, relative density.

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A structural, magnetostrictive and Mssbauer study of Tb0.3Dy0.7(Fe0.9T0.1)1.95 alloys

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Science china(Physics,Mechanics & Astronomy) 2005年第6期Mechanics & Astronomy) .卷 750-756页

作者： ZHENG Xiaoping1,2, ZHANG Peifeng1,3, FAN Duowang1, LI Fashen3 & HAO Yuan4 1. key laboratory of opto-electronic technology and intelligent control, education ministry of china, lanzhou jiaotong university, lanzhou 730070, china 2. lanzhou Teachers College, lanzhou 730070, china 3. key laboratory for Magnetism and Magnetic Materials, education ministry of china, lanzhou university, lanzhou 730000, china 4. State key laboratory of New Nonferrous Metal Materials, lanzhou university of technology, lanzhou 730050, china

The effect of Ⅲ A metal and transition metal T substitution for Fe on crystal structure, magnetostriction and spontaneous magnetostriction, anisotropy and spin reorientation of a series of polycrystalline Tb0.3Dy0.7(Fe0.9T0.1)1.95 (T = Mn, Fe, Co, B, Al, Ga) alloys at room temperature were investigated systematically. It was found that the primary phase of the Tb0.3Dy0.7(Fe0.9T0.1)1.95 alloys is the MgCu2-type cubic Laves phase structure for different substitution. The magnetostriction λs decrases greatly for the substitution of IIIA metal B, Al and Ga, but is saturated more easily for Al and Ga substitution, showing that the Al and Ga substitution is beneficial to a decrease in the magnetocrystalline anisotropy of Tb0.3Dy0.7(Fe0.9T0.1)1.95 alloys. However, the substitution of transition metal Mn and Co decreases slightly the magnetostriction λs. It was also found that the effect of different substitutions on the spontaneous magnetostriction λ111 is distinct. The analysis of the M?ssbauer spectra indicates that the easy magnetization direction in the {110} plane deviates slightly from the main axis of symmetry for Al and Ga substitution, namely spin reorientation, but it does not change evidently for B, Mn and Co substitution.

关键词： magnetostriction cubic Laves phase spin reorientation M?ssbauer.

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Soft Imprint Lithography for Pixel Array Manufacturing in OLED

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兰州交通大学学报 2007年第6期 157-158页

作者： Wang Chenglong1, Fan Duowang1, Liu Hongzhong2(1.key laboratory of opto-electronic technology and Intelligence control,ministry of education,lanzhou jiaotong university,lanzhou 730070,china 2.State key laboratory for Manufacturing Systems Engineering,Xi'an jiaotong university,Xi'an 710049,china)

Introduction During the last two decades,organic light-emitting diodes (OLED) have attracted considerable interest owing to their promising applications by replacing cathode ray tubes (CRTs) or liquid crystal displays... 详细信息

关键词： Soft Imprint Lithography for Pixel Array Manufacturing in OLED PDMS

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Structure, spin reorientation and Mssbauer effect studies of Tb0.3Dy0.7(Fe1-xAlx)1.95 alloys

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Science china(Physics,Mechanics & Astronomy) 2006年第2期Mechanics & Astronomy) .卷 149-157页

作者： ZHENG Xiaoping1,2,4, ZHANG Peifeng1,3, FAN Duowang1, LI Fashen3 & HAO Yuan41. key laboratory of opto-electronic technology and intelligent control, ministry of education, lanzhou jiaotong university, lanzhou 730070, china 2. Institute of electronic Information Science and technology,lanzhou Teachers College, lanzhou 730070, china 3. key laboratory for Magnetism and Magnetic Materials, ministry of education, lanzhou university, Lan-zhou 730000, china 4. State key Lab. of Advanced Non-Ferrous Materials, Gansu Province, lanzhou university of technology, lanzhou 730050, china

The effect of Al substitution for Fe on crystal structure, magnetostriction and spontaneous magnetostriction, anisotropy and spin reorientation of a series of polycrys-talline Tb0.3Dy0.7(Fe1?xAlx)1.95 alloys (x = 0, 0.05, 0.1, 0.15, 0.20, 0.25, 0.30, 0.35) at room temperature and 77 K was investigated systematically. It was found that the primary phase of Tb0.3Dy0.7(Fe1?xAlx)1.95 is the MgCu2-type cubic Laves phase structure when x 0.15 at room temperture, but at 77 K the alloys still remain magnetic phase even for x = 0.2. At room temperature and 77 K, the hyperfine field de-creases and the isomer shifts increase with Al concentration increasing.

关键词： magnetostriction cubic Laves phase spin reorientation M?ssbauer.

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Immune secondary response and clonal selection inspired optimizers

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Progress in Natural Science:Materials International 2009年第2期19卷 237-253页

作者： Maoguo Gong a,Licheng Jiao a,Lining Zhang a,Haifeng Du b a key laboratory of intelligent Perception and Image Understanding of ministry of education of china,Institute of intelligent Information Processing,Xidian university,Xi’an 710071,china b School of Public Policy and Administration,Xi’an jiaotong university,Xi’an 710049,china key laboratory of intelligent Perception and Image Understanding of ministry of education of china Institute of Intelligent Information Processing Xidian University Xi’an 710071 China School of Public Policy and Administration Xi’an Jiaotong University Xi’an 710049 China

The immune system’s ability to adapt its B cells to new types of antigen is powered by processes known as clonal selection and affinity maturation. When the body is exposed to the same antigen,immune system usually calls for a more rapid and larger response to the antigen,where B cells have the function of negative adjustment. Based on the clonal selection theory and the dynamic process of immune response,two novel artificial immune system algorithms,secondary response clonal programming algorithm (SRCPA) and secondary response clonal multi-objective algorithm (SRCMOA),are presented for solving single and multi-objective optimization problems,respectively. Clonal selection operator (CSO) and secondary response operator (SRO) are the main operators of SRCPA and SRCMOA. Inspired by the clonal selection theory,CSO reproduces individuals and selects their improved maturated progenies after the affinity mat-uration process. SRO copies certain antibodies to a secondary pool,whose members do not participate in CSO,but these antibodies could be activated by some external stimulations. The update of the secondary pool pays more attention to maintain the population diversity. On the one hand,decimal-string representation makes SRCPA more suitable for solving high-dimensional function optimiza-tion problems. Special mutation and recombination methods are adopted in SRCPA to simulate the somatic mutation and receptor edit-ing process. Compared with some existing evolutionary algorithms,such as OGA/Q,IEA,IMCPA,BGA and AEA,SRCPA is shown to be able to solve complex optimization problems,such as high-dimensional function optimizations,with better performance. On the other hand,SRCMOA combines the Pareto-strength based fitness assignment strategy,CSO and SRO to solve multi-objective optimization problems. The performance comparison between SRCMOA,NSGA-Ⅱ,SPEA,and PAES based on eight well-known test problems shows that SRCMOA has better performance in converging to approximate Pareto

关键词： Clonal selection Secondary response Artificial immune systems Evolutionary algorithms

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Crystal Structure,UV-vis Absorption and Fluorescent Properties of a Novel Coumarin Derivative

Crystal Structure,UV-vis Absorption and Fluorescent Properti...

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国际纳光电子学研讨会

作者： Peng Zhang(1 student) Tianzhi Yu(2) Yuling Zhao(3) Duowang Fan(4) Author 1 2and 4:key laboratory of opto-electronic technology and intelligent control lanzhou jiaotong university ministry of education lanzhou 730070 People’s Republic of china 3:School of Chemical and Biological Engineering lanzhou jiaotong university lanzhou 730070 People’s Republic of china

＜正＞A novel 3-（1H-4-methyl-benzotriazol-1-yl）-4-methyl-benzo[7,8]coumarin（MBMBC）containing an electron- transporting moiety（benzotriazole）was characterized single crystal X-ray crystallography and UV-vis absorption *** compound exhibits strong blue emission and may prove to be important class of OLED material.

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Optimal user scheduling and power control in multi-user cognitive broadcast systems

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Science china(Information Sciences) 2012年第6期55卷 1402-1414页

作者： WANG QunHuan 1,2,3,WANG HuiMing 1,2,3 & YIN QinYe 1,3 1 School of electronic and Information Engineering,Xi'an jiaotong university,Xi'an 710049,china 2 State key Lab for Integrated Services Networks,Xidian university,Xi'an 710071,china 3 ministry of education key Lab for intelligent Networks and Network Security,Xi'an jiaotong university,Xi'an 710071,china. School of electronic and Information Engineering Xi’an Jiaotong University Xi’an China State key Lab for Integrated Services Networks Xidian University Xi’an China ministry of education key Lab for intelligent Networks and Network Security Xi’an Jiaotong University Xi’an China

Cognitive radio systems should not only have the ability to sense and exploit "frequency spectrum holes",but also the ability to sense and utilize "spatial spectrum holes".In this paper,we consider the issue of maximizing the throughput of the cognitive systems by fully utilizing "spatial spectrum holes" brought in by multiple cognitive users,in the scenario where a pair of licensed users and a cognitive broadcast system share multiple spectrum *** exploiting the channel reciprocity under the premise that the licensed system adopts the time-division-duplexing (TDD) mode,we propose a more practical cognitive access scheme that can sense the interference at the licensed user caused by the cognitive transmitter,based on the existing feedback signals from the licensed user to the licensed base *** both interferences from the licensed base station to the cognitive receiver and from the cognitive transmitter to the licensed user into consideration,we investigate the optimal user scheduling and power allocation scheme that can maximize the ergodic sum rate of the cognitive *** show that scheduling the user whose channel gain to interference and noise ratio (CGINR) is the largest for each frequency band is *** also derive the dynamic power allocation scheme meeting the three practical constraints,i.e.,the transmitter's average transmission power constraint,the power amplifier's instantaneous transmission power constraint,and the interference power constraint at the licensed *** result shows that in different coherent time intervals and different frequency bands,the power allocation has a multi-level waterfilling *** analysis shows that the strategy scheduling user with the largest CGINR introduces significant performance improvement compared with the traditional strategy scheduling user with the largest channel gain to noise ratio (CGNR).We also illustrate the impact of power constraints and the number of users on system p

关键词： cognitive radio distributed spatial spectrum holes opportunistic scheduling power allocation

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Crystal structures and electronic properties of BaC_2 isomers by theoretical study based on DFT

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Science china Chemistry 2008年第6期51卷 545-550页

作者： FENG Jing1,XIAO Bing2 & CHEN JingChao1 1 key laboratory of Advanced Materials of Precious-Nonferrous Metals,education ministry of china,and key Lab of Advanced Materials of Yunnan Province,Kunming university of Science and technology,Kunming 650093,china 2 School of Materials Science and Engineering,Xi’an jiaotong university,Xi’an 710049,china key laboratory of Advanced Materials of Precious-Nonferrous Metals Education Ministry of China Kunming China key Lab of Advanced Materials of Yunnan Province Kunming University of Science and Technology Kunming China School of Materials Science and Engineering Xi’an Jiaotong University Xi’an China

Band structures and electronic properties of two BaC2 isomers were calculated by using density func-tional theory(DFT) *** ionic bond features are all typical between cation(Ba) and anion clusters(C2) in both structures of the ***,a much stronger covalent bond exists in anion clusters which can be seen by inspecting the electron distribution contour that has a dull bell like shape between two carbon *** shortest distance between Ba2+ and C22? and the bond length in anion clusters are different in these isomers of BaC2,which are 0.2945 nm and 0.1185 nm for the structure with the I4/mmm space group and 0.2744 and 0.1136 nm with the C2/c type,*** structures were clarified by combining the DOS to indicate the ionic bonding features more *** analysis provided further evidence on these *** calculation results reveal that the transition temperature of these two polymorphs of BaC2 locates near 132 K,which is consistent with the recent experimental results.

关键词： functional materials metal diaries phase transition electron density first principle calculation orbital bonding state

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High Performance of Fair Bandwidth Allocation Algorithm for an Ethernet PON

High Performance of Fair Bandwidth Allocation Algorithm for ...

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国际纳光电子学研讨会

作者： Guangwu Chen(1) Duowang Fan(2) Zongshou Wei(3) Yafei Fang(4) Yaqiong Qiao(5) key laboratory Opt-electronic technology and intelligent control lanzhou jiaotong university ministry of education lanzhou 730070 People’s Repubilic Of china

＜正＞The paper proposes an optimized CPDBA algorithm,which is based on the characteristics of scheduling mechanism of *** results indicated that the algorithm decreases the daley-time of data packets. Introduction With increasing application of stringencies,EPON quality of service（QoS）has become a major focus, and many dynamic bandwidth allocation（DBA）schemes have been proposed[1].Nevertheless,in practice,a single ONU will host many end-users and this mandates added intra-ONU considerations to ensure end-to-end service guarantees[2].This paper addresses these crucial concerns and is organized as ***（Credit and pdodty based dynamic bandwidth allocation）algorithm is optimized and brought forward in the 1st section of the paper. According to the analysis and simulation of the data packet,which demonstrates the effectiveness of algorithm in a better position to solve the existing problems of delay-time of packet? Finally,the 3rd section summarizes the paper.

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