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Defects Energetics and Electronic Properties of Li Doped ZnO： A Hybrid Hartree-Fock and Density Functional Study

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Chinese Journal of Chemical Physics 2012年第3期25卷 261-268,373页

作者： xu sun You-song Gu xue-qiang Wang Yue Zhang Department of Material Physics and Chemist04 University of Science and Technology Beijing Beij'ing100083 China

The electronic properties and stability of Li-doped ZnO with various defects have been stud- ied by calculating the electronic structures and defect formation energies via first-principles calculations using hybrid Hartree-Fock and density functional methods. The results from formation energy calculations show that Li pair complexes have the lowest formation energy in most circumstances and they consume most of the Li content in Li doped ZnO, which make the p-type conductance hard to obtain. The formation of Li pair complexes is the main obstacle to realize p-type conductance in Li doped ZnO. However, the formation energy of Lizn decreases as environment changes from Zn-rich to O-rich and becomes more stable than that of Li-pair complexes at highly O-rich environment. Therefore, p-type conductance can be obtained by Li doped ZnO grown or post annealed in oxygen rich atmosphere.

关键词： Li doped ZnO Multi-defects Hybrid density functional

On Lu xun’s“Memes”——Taking the Example of the Tie between Lu xun and Shaanxi

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2020年第1期14卷 134-156页

作者： LI Jikai sun xu Institute for Advanced Study of Humanities and Social Sciences School of Chinese Language and Literature Shaanxi Normal UniversityXi’an 710119China

It is of great necessity to observe Lu xun from the human-geographical or cultural geographical *** the couple of corresponding case studies are able to reveal the whole ***“memes”of Lu xun existed in the tie of Lu xun with Shaanxi province,in the existential and imaginary relationships between him and the two cities of“An”(Xi’an and Yan’an),in Lu xun studies conducted by Shaanxi’s academic community,and in a variety of cultural events and phenomena such as Shaanxi writers,publications,as well as conferences and calligraphy activities in Shaanxi,are hinting from the indirect aspects at the profound impacts of Lu xun over the modern and contemporary culture in *** transmission,reception and transformation of Lu xun in Shaanxi during various historical stages also indicate the changes occurring to political ideology,aesthetic judgment,values and academic *** discuss Lu xun’s“memes”in the regional culture of Shaanxi,which closely combines the region in the physical sense of cultural geography and Lu xun study,is an important component of Lu xun studies,as well as an effective path to delve into the research on the ties of Lu xun with China,or even with the world,for the further attempt to comprehensively understand the significance and value of Lu xun to the new culture in China,as well as to the modern and contemporary culture.

关键词： the May Fourth Movement Lu xun memes Shaanxi

Optimal Feeder Routing in Urban Distribution Networks Planning with Layout Constraints and Losses

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Journal of Modern Power Systems and Clean Energy 2020年第5期8卷 1005-1014页

作者： Alessandro Bosisio Alberto Berizzi Edoardo Amaldi Cristian Bovo xu Andy sun IEEE Department of Energy Politecnico di MilanoVia La Masa3420165 MilanoItaly Department of Electronics Informationand BioengineeringPolitecnico di MilanoVia Ponzio34/520133 MilanoItaly H.Milton Stewart School Georgia Institute of Technology775 Ferst DriveAtlanta GA 30332USA

We address the problem of optimally re-routing the feeders of urban distribution network in Milano,Italy,which presents some peculiarities and significant design *** has two separate medium-voltage(MV)distribution networks,previously operated by two different utilities,which grew up independently and *** results in a system layout which is inefficient,redundant,and difficult to manage due to different operating *** current utility UNARETI,which is in charge of the overall distribution system,aims at optimally integrating the two MV distribution networks and moving to a new specific layout that offers advantages from the perspectives of reliability and *** present a mixed-integer programming(MIP)approach for the design of a new network configuration satisfying the so-called 2-step ladder layout required by the *** model accounts for the main electrical constraints such as power flow equations,thermal limits of high-voltage(HV)/MV substation transformers,line thermal limits,and the maximum number of customers per *** power losses are taken into account via a quadratic formulation and a piecewise linear *** tests on a small-scale system and on a part of the Milano distribution network are reported.

关键词： Mixed-integer programming(MIP) graph theory power system planning urban distribution network feeder routing optimization

Early-age Hydration Characteristics of Composite Binder Containing Graphite Powder

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Journal of Wuhan University of Technology(Materials Science) 2022年第6期37卷 1252-1261页

作者： HE Wei SONG Shaomin MENG Xia ZHANG Pengchong sun xu School of Civil and Transportation Engineering Beijing University of Civil Engineering and ArchitectureBeijing 100044China Architectural Design and Research Institute of Tsinghua University Co. Ltd.Beijing 100084China

The early-age hydration characteristics of composite binder containing graphite powder(GP)with two different finenesses were investigated by determining the hydration heat,thermo gravimetric,morphology of hardened paste as well as the compressive strength of *** experimental results show that:replacing 2%-6%of cement with graphite powder significantly improves the piezoresistive effect of early age mortar,can be used to monitor accidental loads caused by dropped objects,collisions,or other accident events,and thus avoids initial *** GP provides additional nucleation sites that lead to a fast formation of hydration products(nucleation-site effect).However,due to the almost hydrophobic water contact angle,most of the GP causes a large number of micro-cracks in the hydrated paste(gap effect).Because of the lamellar shape and high surface energy,GP is easily balled and can not be uniformly distributed in the composite,resulting in clumping together and wrapping some of the cement particles(barrier effect).Due to nucleation-site effect,when the dosages of coarse and fine GP reached 2%and 4%,1 d strength were increased by 9.1%and 9.6%,*** 3 days,as the interior damage caused by the gap effect gradually increased,and the retarding effect on cement hydration caused by barrier effect was *** has an obvious negative effect on compressive ***,micro-cracks caused by fine GP are less,so its negative effect on 3 d compressive strength is lower.

关键词： graphite powder Portland cement early-age hydration piezoresistive effect comprehensive strength

Vehicle LED detection and segmentation recognition based on deep learning for optical camera communication

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Optoelectronics Letters 2022年第8期18卷 508-512页

作者： CHENG Qing MA Haitao sun xu Department of Communications Engineering Jilin UniversityChangchun 130012China

In the vehicle to vehicle(V2V)communication based on optical camera communication(OCC)system,how to achieve high reliability and low latency communication is still a *** this paper,we propose a lightweight light-emitting diode(LED)detection algorithm based on deep learning to detect the vehicle LED position at different communication distances,which can improve LED detection accuracy and inference *** addition,we design an LED segmentation recognition algorithm to reduce the bit error rate(BER)of the vehicle OCC *** experimental results demonstrate the effectiveness of the proposed algorithms in real traffic scenes.

关键词： optical communication algorithm

Research on optimization design method of actuator parameters with stepless capacity control system for reciprocating compressor

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High Technology Letters 2020年第2期26卷 168-177页

作者： Zhou Chao Zhang Jinjie sun xu Wang Yao Compressor Health and Intelligent Monitoring Center of National Key Laboratory of Compressor Technology Beijing University of Chemical TechnologyBeijing 100029P.R.China State Key Laboratory of Compressor Technology Anhui Provincial Laboratory of Compressor TechnologyHefei 230031P.R.China Beijing Key Laboratory of Health Monitoring Control and Fault Self-Recovery for High-End Machinery Beijing University of Chemical TechnologyBeijing 100029P.R.China

Actuator and hydraulic system parameters have great influence on the performance,safety and reliability of the stepless capacity control system of reciprocating *** to the diversity and complex relationship of parameters,traditional parameters selected and calculated based on feasibility can’t make the system run efficiently,have limitations,and may have adverse effects on the system or ***,taking the spring stiffness of the actuator and the impact velocity of ejection,the inlet oil pressure of the hydraulic system,and the indicated power deviation of the compressor as objective functions,the multi-parameter and multi-objective optimization research of the actuator and hydraulic system with the stepless capacity control system based on non-dominated sorting genetic algorithm II(NSGA-II)is carried *** on fuzzy analytic hierarchy process(FAHP),the optimal solution is selected from the Pareto front,and compared with the traditional design value,the result is better than that obtained by the traditional design method.

关键词： reciprocating compressor stepless capacity control system non-dominated sorting genetic algorithm II(NSGA-II) fuzzy analytic hierarchy process(FAHP)

A Novel laser scanning method for metallization of alumina substrate by copper

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Rare Metals 2023年第3期42卷 844-852页

作者： Yu Hui Zhao-Lin Na Bo-Ming sun xu-Dong sun Jia-Lin Chen Liaoning Engineering Laboratory of Special Optical Functional Crystals College of Environmental and Chemical EngineeringDalian University Department of Chemistry Imperial College LondonLondon W120BZUK Institute of Ceramics and Powder Metallurgy School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals Kunming Institute of Precious MetalsKunming 650106China

A laser scanning method was developed to metalize the surface of alumina substrates with *** modeling of the heating and cooling rates of the samples during the laser scanning process indicates that the metallization process involves the rapid melting and solidification of Al_(2)O_(3) and Cu and the evaporation and deposition of part of the *** surface of the metalized alumina substrate was composed of copper spheres(~60μm in diameter)embedded into the alumina substrate and a thin layer of CuAlO_(2).

关键词： solidification copper laser

A new cyclostellettamine from sponge Amphimedon compressa

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Chinese Chemical Letters 2007年第8期18卷 947-950页

作者： Nian Jun xu xue sun Xiao Jun Yan Key Laboratory of Marine Biotechnology Faculty of Life Science and Biotechnology Ningbo University Ningbo 315211 China

A new compound, 8,8＇-dienecyclostellettamine, was isolated from the marine sponge Amphimedon compressa. Its structure was elucidated by spectroscopic methods including 1D and 2D NMR, UV, IR, ESI-MS, MALDI-MS techniques. It is probably an important precursor of the manzamine alkoids, and also showed vigorous antibacterial activities.

关键词： Amphimedon compressa Antibacterial 8,8'-Dienecyclostellettamine

InGaP/InGaAs/GaAs DHBT structural materials grown by GSMBE

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Rare Metals 2006年第z2期25卷 20-23页

作者： AI Likun xu Anhuai sun Hao ZHU Fuying QI Ming State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China Graduate School of Chinese Academy of Sciences Beijing 100039 China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China

Heterojunction bipolar transistor (HBT) is of great interest for the application to microwave power and analog circuits. As known, decreasing bandgap energy of the base layer in HBT can result in a smaller turn-on voltage. Using InGaAs as a base material in GaAs HBT is a possible approach to achieve the aim. In this work, a novel InGaP/InGaAs/GaAs double heterojunction bipolar transistor (DHBT) structure with an InGaAs base was designed and grown by gas source molecular beam epitaxy (GSMBE). High-quality InGaAs/GaAs hetero epi-layers and a good doping figure were obtained through optimizing the layer structure and the growth condition. The DHBT devices of a 120 μm×120 μm emitter area were fabricated by normal process and the good DC performance was obtained. A breakdown voltage of 10 V and an offset voltage of just 0.4 V were achieved. These results indicate that the InGaP/InGaAs/GaAs DHBT is suitable for low power-dissipation and high power applications.

关键词： double heterojunction bipolar transistor (DHBT) gas source molecular beam epitaxy (GSMBE) gallium arsenic (GaAs) indium gallium arsenic (InGaAs)