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Implementation of a multiple round quantum dense coding using nuclear magnetic resonance

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science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 706-715页

作者： ZHANG Jingfu1, XIE Jingyi2, WANG Chuan1, DENG Zhiwei3, LU Zhiheng4, & LONG Guilu1,5 1. Key Laboratory For Quantum Information and Measurements of MOE, department of Physics, Tsinghua university, beijing 100084,china 2. department of materials science and engineering, beijing normal university, beijing 100875, china 3. Testing and Analytical Center, beijing normal university, beijing 100875,china 4. department of Physics, beijing normal university, beijing 100875, china 5. Key Laboratory For atomic and Molecular Nanosciences, Tsinghua university, beijing 100084,china Key Laboratory For Quantum Information and Measurements Department of Physics Tsinghua University Beijing 100084 China department of materials science and engineering Beijing Normal University Beijing 100875 China Testing and Analytical Center Beijing Normal University Beijing 100875 China department of Physics Beijing Normal University Beijing 100875 China Key Laboratory for Atomic and Molecular Nanosciences Tsinghua University Beijing 100084 China

A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance (NMR) quantum computer. Using an m + 1 qubit system, Bob can transmit one of 2m+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m + 1 bits as compared to m bits in a classical scheme. The scheme has been demonstrated in NMR system, and the experimental results show a good agreement between theory and experiment.

关键词： quantum dense coding, multiple round, nuclear magnetic resorance

Compatibility between glass sealants and electrode materials of solid oxide fuel cells

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Rare Metals 2008年第4期27卷 378-383页

作者： PIAO Jinhua SUN Kening Chen Xinbing department of Applied Chemistry Harbin Insstnte of Technology Harbin 150001 China department of materials science and engineering Beijing Normal University Beijing 100875 China

BaO-CaO-Al2O3-SiO2-La2O3-B2O3 system glass materials were investigated as sealants for a solid oxide fuel cell （SOFC）. The transition temperature （Tg and the crystal temperature （Td） values decrease greatly with the increase of BaCO3 content when the other components do not change. For the thermal expansion coefficient （TEC） values, the trend is inverse. The sealant has superior thermal expansion coefficient matching properties with La（Sr）MnO3 （LSM） cathode, La（Sr）FeO3 （LSF） cathode, Ni-LDC （La doped CeO2） anode, and Ni-YSZ （yttria stabilized zirconia） cermet anode. The sealant also has superior stability, compatibility, and good bonding characteristic with these electrode materials at 800-900℃. The results indicate that the aluminosilicate system glass sealant possesses superior compatibility with electrode materials of the solid oxide fuel cell

关键词： solid oxide fuel cell aluminosilicate sealant glass-ceramic compatibility interface

Synthesis of vertically aligned carbon nanotube arrays on silicon substrates

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science china(Technological sciences) 2004年第5期47卷 616-624页

作者： ZHENG Ruiting1, CHENG Guoan1, PENG Yibin1, 2, ZHAO Yong1, 3, LIU Huaping1 & LIANG Changlin1 1. Key Laboratory of Radiation Beam Technology and materials Modification of Ministry of Education, department of materials science and engineering, beijing normal university, beijing 100875, china 2. School of science, Civil Aviation university of china, Tianjin 300300, china 3. department of Physics, Nanchang university, Nanchang 330047, china Correspondence should be addressed to Zheng Ruiting Key Laboratory of Radiation Beam Technology and materials Modification of Ministry of Education Department of Materials Science and Engineering Beijing Normal University Beijing China School of science Civil Aviation University of China Tianjin China department of Physics Nanchang University Nanchang China

The growth of well-aligned carbon nanotube (CNT) arrays using a heat chemical vapor deposition system on silicon substrates is reported. The growth properties of CNT arrays are studied as a function of synthesis conditions. It is found that 750°C and 10 nm Fe film are suitable conditions for the growth of well-aligned CNT arrays. CNT arrays with a uniform diameter, thick tube wall and firm cohesion to the Si substrate can be grown for C2H2 concentration of 27%. Based on the experiment, the processes of improving the alignment of CNT arrays and cohesion between CNT arrays and Si substrates are discussed.

关键词： carbon nanotubes, vertically aligned, silicon substrate, chemical vapor deposition.

Photoluminescence and radiation effect of Er and Pr implanted silicon-rich silicon oxide thin films

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Photoluminescence and radiation effect of Er and Pr implante...

Recommendation Method for Contrastive Enhancement of Neighborhood Information

9th International Conference on Computer Simulation of Radiation Effects in Solids

作者： Fang Zhu~1,Zhisong Xiao~(1,*),Lu Yan~1,Feng Zhang~1,Kun Zhong~2,Guoan Cheng~2 1 department of Physics,School of science,Beihang university,beijing 100191,china 2 department of materials science and engineering,beijing normal university,beijing 100875,china

Er and Pr ions were implanted into silicon-rich silicon oxide(SRSO) thin films with Si nanocrystals embedded in SiO *** 524 and 548 nm luminescence peaks were clearly observed in Er-only doped film,but disappeared fro... 详细信息

关键词： Er Pr SRIM Si/SiO2 photoluminescence

来源： cnki会议评论

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cnki会议

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Computers, materials & Continua 2024年第1期78卷 453-472页

作者： Hairong Wang beijing Zhou Lisi Zhang He Ma School of Computer science and engineering North Minzu UniversityNingxia750021China

Knowledge graph can assist in improving recommendation performance and is widely applied in various person-alized recommendation ***,existing knowledge-aware recommendation methods face challenges such as weak user-item interaction supervisory signals and noise in the knowledge *** tackle these issues,this paper proposes a neighbor information contrast-enhanced recommendation method by adding subtle noise to construct contrast views and employing contrastive learning to strengthen supervisory signals and reduce knowledge ***,first,this paper adopts heterogeneous propagation and knowledge-aware attention networks to obtain multi-order neighbor embedding of users and items,mining the high-order neighbor informa-tion of users and ***,in the neighbor information,this paper introduces weak noise following a uniform distribution to construct neighbor contrast views,effectively reducing the time overhead of view *** paper then performs contrastive learning between neighbor views to promote the uniformity of view information,adjusting the neighbor structure,and achieving the goal of reducing the knowledge noise in the knowledge ***,this paper introduces multi-task learning to mitigate the problem of weak supervisory *** validate the effectiveness of our method,experiments are conducted on theMovieLens-1M,MovieLens-20M,Book-Crossing,and Last-FM *** results showthat compared to the best baselines,our method shows significant improvements in AUC and F1.

关键词： Contrastive learning knowledge graph recommendation method

ENERGY FLOWS IN COMPLEX ECOLOGICAL SYSTEMS:A REVIEW

维普期刊数据库评论

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维普期刊数据库

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Journal of Systems science & Complexity 2009年第3期22卷 345-359页

作者： Jiang ZHANG department of Systems science,School of Management,beijing normal university,beijing 100875,china. department of Systems science School of Management Beijing Normal University Beijing China

Energy flow drives the complex systems to *** allometric scaling as the universalenergy flow pattern has been found in different scales of ecological *** reflects the generalpower law relationship between flow and *** underlying mechanisms of energy flow patterns areexplained as the branching transportation networks which can be regarded as the result of systematicoptimization of a biological target under *** flows in the ecological system may bemodelled by the food web model and population dynamics on the *** paper reviews thelatest progress on the energy flow patterns,explanatory models for the allometric scaling and modellingapproach of flow and network evolution dynamics in ***,the possibility of generalizingthese flow patterns,modelling approaches to other complex systems is discussed.

关键词： Allometric scaling energy flow flows in complex systems food web.

Recovery of functions via their irregular sampling values

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Chinese science Bulletin 1998年第4期43卷 268-271页

作者： FANG Gensun department of Mathematics, beijing normal university, beijing 100875, china department of Mathematics Lkijing Normal University Beijing China

It is proved that if a function can be completely reconstructed by tempered splines which satisfy the real Kiesz basis condition as the degree of spline goes to infinity, then the function is band limited.

关键词： band limited function cardinal splines irregular sampling.

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Saturated models

Chinese science Bulletin 1998年第7期43卷 562-564页

作者： CHEN Guolong department of Mathematics, beijing normal university, beijing 100875, china department of Mathematics Beijing Normal University Beijing China

An equivalent description of saturated models is given, and some properties of countable saturated models, almost saturated models and full models are discussed. New proofs of two important theorems of the related doc... 详细信息

关键词： almost saturated model full model power type.

TEXTURE DETERMINATION OF THIN FILM ZrO_2 BY ELECTRON DIFFRACTION

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Acta Metallurgica Sinica(English Letters) 1993年第12期6卷 472-473页

作者： WANG Yinghua Tsinghua university,beijing,china department of materials science and engineering,Tsinghua university,beijing 100084,china Tsinghua Univ Beijing China

A method for semi-quantitative determination of thin film texture using electron diffrac- tion is *** texture state of a zirconia thin film with a cubic structure has been determined in this way and is presented as an... 详细信息

关键词： texture thin film electron diffraction ZrO_2