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(K_(0.5)Na_(0.5))Nb_(1-x)Ta_(x)O_(3)铁电性的第一性原理研究

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原子与分子物理学报 2025年第4期42卷 138-146页

作者：褚新建雷博程刘晨曦刘纪博新疆科技学院信息科学与工程学院库尔勒841000 新疆大学物理科学与技术学院新疆固体物理与器件重点实验室乌鲁木齐830046 西安工业大学光电工程学院西安710032

随着铅基陶瓷的大量使用,造成了严重的环境和健康问题,为了能够找寻替代铅基陶瓷的材料,人们开始了对无铅陶瓷材料的探索.(K_(0.5)Na_(0.5))Nbo_(3)材料由于其优异的铁电压电性能,成为了无铅陶瓷材料的代表,但是碱性组分在高温下的高挥... 详细信息

随着铅基陶瓷的大量使用,造成了严重的环境和健康问题,为了能够找寻替代铅基陶瓷的材料,人们开始了对无铅陶瓷材料的探索.(K_(0.5)Na_(0.5))Nbo_(3)材料由于其优异的铁电压电性能,成为了无铅陶瓷材料的代表,但是碱性组分在高温下的高挥发性使其应用范围受到了极大的限制.基于这样的考虑,本文基于密度泛函理论的第一性原理方法,探究了(K_(0.5)Na_(0.5))Nb_(1-x)TaxO_(3)(x=0.125,0.25,0.375,0.5,0.625,0.75,0.875,1)九种体系的铁电性能,结果表明:随着Ta浓度的增加,晶格常数发生了突变,由此猜测KNN材料随着Ta浓度的增加,发生了正交-单斜的相变;Ta的掺入能够降低KNN材料的烧结难度,且随着Ta浓度的增加,形成难度逐渐降低;掺杂体系中,Ta-4f轨道与Na-3p,K-4p以及O-2s轨道电子发生了杂化,使导带底Nb-4d与Na-3p电子的态密度峰向高能区移动,禁带宽度呈现增加的趋势;在分析KNN材料铁电性作用机理时发现KNN的铁电极化类型是离子位移型极化,且在[001]方向上不具有极化能力.分析掺杂后各个体系的极化强度,发现随着Ta浓度的增加,极化强度逐渐降低,但是在低浓度掺杂时极化有向上增加的趋势,这可能是体系在低浓存在着正交与单斜的准同型相界(Morphotropic phase boundary,MPB)导致的,由此可以判断,低浓度掺杂有利于提高KNN材料的铁电性能.

关键词：第一性原理钙钛矿结果 KNN 铁电性

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Efficient quantum private comparison protocol based on one direction discrete quantum walks on the circle

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Chinese Physics B 2022年第5期31卷 150-156页

作者： Jv-Jie Wang Zhao Dou xiu-bo chen Yu-Ping Lai Jian Li Information Security Center State Key Laboratory of Networking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing 100876China Information Security Center School of Cyberspace SecurityBeijing University of Posts and TelecommunicationsBeijing 100876China

We propose an efficient quantum private comparison protocol firstly based on one direction quantum *** the help of one direction quantum walk,we develop a novel method that allows the semi-honest third party to set a flag to judge the comparing result,which improves the qubit efficiency and the maximum quantity of the participants’secret ***,our protocol can judge the size of the secret messages,not only ***,the quantum walks particle is disentangled in the initial *** only requires a quantum walks operator to move,making our proposed protocol easy to implement and reducing the quantum *** security analysis,we prove that our protocol can withstand well-known attacks and brute-force *** also reveal that our protocol is correct and practical.

关键词： quantum private comparison protocol one direction quantum walks efficiency brute-force attack

Synthesis, Crystal Structure and Reactivity of (2,4-C_7H_(11) )_2Yb·DME

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Chemical Research in Chinese Universities 2001年第1期17卷 14-19页

作者： ZHANG Suo-bo LIU Ju-zheng ZHUANG xiu-li HUANG Jing-qin HU Ning-hai chen Wen-qi Department of Chemistry Jilin UniversityChangchun 130023P.R.China Changchun Institute of Applied Chemistry Chinese Academy of SciencesChangchun 130022P.R.China

(2,4 C 7H 11 ) 2Yb·DME was synthesized by the reaction of YbCl 3 with K(2,4 C 7H 11 )(2,4 dimethylpentadienyl potassium), and the single crystal X ray diffraction showed that the complex exists in a cis staggered conformation. The crystal of the compound belongs to the monoclinic space group P2 1/n with a =0.875 2 (1) nm, b =1.490 6(1) nm, c =1.529 3(2) nm, β =97 55(2)° , V =1.977 79(4) nm 3, Z =4, F (000)=735.8 e, μ =49.49 cm -1 , R =0.033 and R w=0.032 . The title complex can be used as a catalyst for the polymerization of methyl methacrylate(MMA).

关键词： Dimethylpentadienyl Synthesis Crystal structure Catalyst Polymerization

Predicting CircRNA-Disease Associations Based on Improved Weighted Biased Meta-Structure

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Journal of Computer Science & Technology 2021年第2期36卷 288-298页

作者： xiu-Juan Lei chen Bian Yi Pan School of Computer Science Shaanxi Normal UniversityXi'an 710119China School of Computer Science and Control Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Department of Computer Science Georgia State UniversityAtlantaGA 30302U.S.A

Circular RNAs(circRNAs)are RNAs with a special closed loop structure,which play important roles in tumors and other *** to the time consumption of biological experiments,computational methods for predicting associations between circRNAs and diseases become a better *** the limited number of verified circRNA-disease associations into account,we propose a method named CDWBMS,which integrates a small number of verified circRNA-disease associations with a plenty of circRNA information to discover the novel circRNA-disease *** adopts an improved weighted biased meta-structure search algorithm on a heterogeneous network to predict associations between circRNAs and *** terms of leave-one-out-cross-validation(LOOCV),10-fold cross-validation and 5-fold cross-validation,CDWBMS yields the area under the receiver operating characteristic curve(AUC)values of 0.9216,0.9172 and 0.9005,***,case studies show that CDWBMS can predict unknow circRNA-disease *** conclusion,CDWBMS is an effective method for exploring disease-related circRNAs.

关键词： circular RNA(circRNA) circRNA-disease association meta-structure heterogeneous network

Performance Investigation of All-Optical NRZ-to-Manchester Format Conversion with SOA-MZI Based XOR Logic Gate

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Chinese Physics Letters 2011年第2期28卷 112-115页

作者： chen Jian-bo ZHOU Rui ZHANG Qi YU Chong-xiu XIN Xiang-Jun Institute of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876

All-optical format conversion between non-return-to-zero(NRZ)and the Manchester code is implemented by using an optical exclusive-OR(XOR)logic gate based on a semiconductor optical amplifier Mach-Zehnder Interferometer(SOA-MZI).There is 10 Gbit/s all-optical NRZ-to-Manchester conversion implemented in our simulation system and BER performance of the format conversion is *** performances of the converted Manchester coded signal are discussed in terms of transmission length and received optical power.

关键词： NRZ SOA Manchester

boundary Control of Coupled Non-Constant Parameter Systems of Time Fractional PDEs with Different-Type boundary Conditions

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Journal of Systems Science & Complexity 2023年第1期36卷 273-293页

作者： chen Juan ZHUANG bo Aliyun School of Big Data Changzhou UniversityChangzhou 213164China School of Information Engineering Binzhou UniversityBinzhou 256600China

This paper addresses a boundary state feedback control problem for a coupled system of time fractional partial differential equations(PDEs)with non-constant(space-dependent)coefficients and different-type boundary conditions(BCs).The BCs could be heterogeneous-type or ***,this coupled system has different BCs at the uncontrolled side for heterogeneous-type and the same BCs at the uncontrolled side for *** main contribution is to extend PDE backstepping to the boundary control problem of time fractional PDEs with space-dependent parameters and different-type *** the backstepping transformation and the fractional Lyapunov method,the Mittag-Leffler stability of the closed-loop system is obtained.A numerical scheme is proposed to simulate the fractional case when kernel equations have not an explicit solution.

关键词： boundary control coupled systems heterogeneous mittag-leffler stability time fractional PDEs with space-dependent coefficients

Efficient quantum private comparison protocol utilizing single photons and rotational encryption

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Chinese Physics B 2022年第6期31卷 221-227页

作者： Tian-Yi Kou Bi-chen Che Zhao Dou xiu-bo chen Yu-Ping Lai Jian Li Information Security Center State Key Laboratory of Networking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing 100876China Information Security Center School of Cyberspace SecurityBeijing University of Posts and TelecommunicationsBeijing 100876China

As a branch of quantum secure multiparty computation,quantum private comparison is applied frequently in many fields,such as secret elections,private voting,and identification.A quantum private comparison protocol with higher efficiency and easier implementation is proposed in this *** private secrets are encoded as single polarized photons and then encrypted with a homomorphic rotational encryption *** on this method and the circular transmission mode,we implement the multiplexing of photons,raising the efficiency of our protocol to 100%.Our protocol is easy to realize since only single photons,unitary operation,and single-particle measurement are ***,the analysis shows that our protocol is also correct and secure.

关键词： quantum private comparison rotational encryption polarized single photons efficiency

Transcriptional Regulation of Plant Secondary Metabolism

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Journal of Integrative Plant Biology 2012年第10期54卷 703-712页

作者： Chang-Qing Yang Xin Fang xiu-Ming Wu Ying-bo Mao Ling-Jian Wang Xiao-Ya chen National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and Ecology Shanghai Institutes for BiologicalSciences the Chinese Academy of Sciences Shanghai 200032 China plant Science Research Center. Shanahai chensh-an botanical Garden. Shanahai 201602. China

Plant secondary metabolites play critical roles in plant-environment interactions. They are synthesized in different organs or tissues at particular developmental stages, and in response to various environmental stimuli, both biotic and abiotic. Accordingly, corresponding genes are regulated at the transcriptional level by multiple transcription factors. Several families of transcription factors have been identified to participate in controlling the biosynthesis and accumulation of secondary metabolites. These regulators integrate internal （often developmental） and external signals, bind to corresponding cis-elements -- which are often in the promoter regions -- to activate or repress the expression of enzyme-coding genes, and some of them interact with other transcription factors to form a complex. In this review, we summarize recent research in these areas, with an emphasis on newly-identified transcription factors and their functions in metabolism regulation.

关键词： Alkaloid phenylpropanoid secondary metabolism terpenoid transcription factor.

Assessments of coefficients of linear thermal expansions for magnetic elements Fe, Co and Ni

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Rare Metals 2016年第6期35卷 481-486页

作者： Dan Li Xiao-bo Li bo Zhang chen chen School of Mechanical Engineering Xiangtan University Xiangtan 411105 China Key Laboratory of Materials Design and Preparation Technology of Hunan Province Xiangtan 411105 China

The coefficients of linear thermal expansions （CLEs） of magnetic elements Fe, Co and Ni were assessed from experimental information using theoretical models combined with MATLAB calculations. Model parameters can be determined accurately, and the assessed data are in good agreement with the experimental results. To facilitate the assessments, theories of thermal expansion were applied to separate CLEs into its nonmagnetic and magnetic components. The calculations of nonmagnetic contribution to CLEs were based on the modified Gruineisen- Debye model, in which the Debye temperature was regarded as an undetermined constant. In order to put the prediction of CLEs at the magnetic transition region on a sound physical basis, two kinds of theoretical models were innovatively used to calculate the magnetic contribution to CLEs, i.e., the Bragg-Williams model and the Fermi-Dirac distribution function. Model parameters were evaluated from experimental data using least square method. Detailed comparisons were made with the published experimental data and the calculated total CLEs. A satisfactory agreement is reached.

关键词： Coefficients of linear thermal expansion Magnetic elements Theoretical models