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Structure and Aromaticity of AlCO-substituted Semibullvalene

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Chinese Journal of Structural Chemistry 2007年第8期26卷 897-901页

作者： yao wen-Zhi WU Hai-Shun Chemistry and Material Science Institute Shanxi Normal University Linfen 041004 China

The structures, energies and aromaticity （the nuclear-independent chemical shifts,NICS） of AlCO-substituted semibullvalenes were investigated at the B3LYP/6-311＋G＊＊ *** to BCO-substituted analogues, [2,6]-AlCO-semibullvalene is neutral *** NICS values reveal that the aromaticity of AlCO-substituted structures is smaller than that of BCO analogues.

关键词： DFT semibullvalene AlCO aromaticity

Is playing-as-downloading feasible in an eMule P2P file sharing system?

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第6期11卷 465-475页

作者： wen-yi WANG yao-wu CHEN Advanced Digital Technology and lnstruments Institute Zhejiang University Hangzhou 310027 China

Peer-to-peer(P2P) swarm technologies have been shown to be very efficient for large scale content distribution systems, such as the well-known BitTorrent and eMule ***, these systems have been designed for generic file sharing with little consideration of media streaming support, and the user cannot start a movie playback before it is completely *** playing-as-downloading capability would be particularly useful for a downloading peer to evaluate if a movie is valuable to be downloaded, and it could also help the P2P content distribution system to locate and eliminate the polluted *** this paper we address this issue by introducing a new algorithm, wish driven chunk distribution(WDCD), which enables the P2P file sharing system to support the video-on-demand(VOD) function while keeping the P2P native downloading speed.A new parameter named next-play-frequency is added to the content chunk to strike a replication balance between downloading and streaming *** modify the eMule as the test bed by adding the WDCD algorithm and then verify the prototype implementation by *** experimental results show that the proposed algorithm can keep the high downloading throughput performance of the eMule system with a good playing-as-downloading function.

关键词： Peer-to-peer(P2P) Video-on-demand(VOD) Playing-as-downloading eMule

Acyclic Edge Coloring of Triangle-free 1-planar Graphs

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Acta Mathematica Sinica,English Series 2015年第10期31卷 1563-1570页

作者： wen yao SONG Lian Ying MIAO Institute of Mathematics China University of Mining and TechnologyXuzhou

A proper edge coloring of a graph G is acyclic if there is no 2-colored cycle in G. The acyclic chromatic index of G, denoted by X＇a（G）, is the least number of colors such that G has an acyclic edge coloring. A graph is 1-planar if it can be drawn on the plane so that each edge is crossed by at most one other edge. In this paper, it is proved that X＇a（G） ≤△ A（G）＋ 22, if G is a triangle-free 1-planar graph.

关键词： Acyclic chromatic index acyclic edge coloring 1-planar graph

The dynamic response of a high-density polyethylene slow-release structure under launching overload

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Defence Technology（防务技术） 2023年第8期26卷 143-156页

作者： Ke-Bin Zhang wen-Bin Li Yu Zheng wen-Jin yao Chang-Fang Zhao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China

Based on the 60 mm artillery grenade,a slow-release structure was designed to reduce the severity of ammunitions response to accidental thermal stimulation and improve the thermal stability of *** slow-release structure was made of high-density polyethylene(HDPE) and connected the fuse and the projectile body through internal and external *** study the safety of the slowrelease structure under artillery launching overload,mechanical analysis of the slow-release structure was simulated via finite element analysis(FEA).The impacts of various factors(e.g.,fuse mass,number of threads,and nominal diameter of internal threads of the slow-release structure) on the connection strength of the slow-release structure were studied.A strength-prediction model based on the fuse mass and internal thread parameters was established by fitting the maximum effective stress of the slowrelease *** led to good prediction *** conclusion,this study provides references and theoretical support for the design of thermal protection structures insensitive to ammunition.

关键词： Artillery ammunition HDPE Finite element analysis Slow-release structure Threaded connection

A novel current-sharing scheme based on magamp

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第8期9卷 1150-1156页

作者： wen-xi yao Xiao-yuan HONG Zheng-yu LU School of Electrical Engineering Zhejiang University Hangzhou 310027 China

The magamp (magnetic amplifier) is widely used in power supplies due to its low cost, simplicity and other advan-tages. This paper discusses a novel application of the magamp in switching power supplies, where the magamp is used to regulate pulse width modulation (PWM) instead of power signal in the main circuit. This method extends the application of the magamp in power supplies, and makes it possible to further regulate control signal when PWMs have been generated. Based on this applica-tion, a new current-sharing (CS) scheme using the magamp is proposed, which uses a modified inner loop CS structure. In this scheme PWMs are generated by one main controller, and CS is achieved by regulating PWMs using a magamp in each module. Compared with traditional application of the magamp, the new CS scheme can be used in most topologies and only requires magamps of low power capacity. Then a test circuit of parallel power supply is developed, in which CS is achieved by a PWM regulator with the magamp. The proposed scheme is also used to upgrade an electroplate power to make it capable of paralleling supplies. Experimental results show that the proposed scheme has good CS performance.

关键词： Current-sharing (CS) Magnetic amplifier (magamp) Parallel

Reducing porcine corneal graft rejection, with an emphasis on porcine endogenous retrovirus transmission safety: a review

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International Journal of Ophthalmology(English edition) 2019年第2期12卷 324-332页

作者： yao-wen Song Zhi-Qiang Pan Beijing Tongren Eye Center Beijing Tongren Hospital Capital Medical University Beijing Ophthalmology and Visual Science Key Laboratory

Donor cornea shortage is a primary hurdle in the development of corneal transplantation. Of all species, porcine corneas are the ideal transplantation material for humans. However, the xenoimmune rejection induced by porcine corneal xenotransplantation compromises surgical efficacy. Although the binding of IgM/IgG in human serum to a genetically modified porcine cornea is significantly weaker than that of the wild type(WT), genetically modified porcine corneas do not display a prolonged graft survival time in vivo. Conversely, costimulatory blockade drugs, such as anti-CD40 antibodies, can reduce the xenoimmune response and prolong graft survival time in animal experiments. Moreover, porcine endothelial grafts can survive for more than 6mo with only the subconjunctival injection of a steroid-based immunosuppressants regime; therefore, they show great value for treating corneal endothelial disease. In addition, zoonotic transmission is a primary concern of xenotransplantation. Porcine endogenous retrovirus(PERV) is the most significant virus assessed by ophthalmologists. PERV integrates into the porcine genome and infects human cells in vitro. Fortunately, no evidence from in vivo studies has yet shown that PERV can be transmitted to hosts.

关键词： corneal xenotransplantation genetically modified pigs wild type pigs costimulatory blockade drugs porcine endothelial grafts porcine endogenous retrovirus safety

Morphological and molecular response of small intestine to lactulose and hydrogen-rich water in female piglets fed Fusarium mycotoxins contaminated diet

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Journal of Animal Science and Biotechnology 2019年第3期10卷 694-707页

作者： Xu Ji Qing Zhang Weijiang Zheng wen yao Laboratory of Gastrointestinal Microbiology Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal HealthCollege of Animal Science and TechnologyNanjing Agricultural UniversityNanjing 210095JiangsuChina Key Lab of Animal Physiology and Biochemistry Ministry of AgricultureNanjing 210095JiangsuChina

Background: Following the intake of Fusarium mycotoxin-contaminated feed,small intestines may be exposed to high levels of toxic substances that can potentially damage intestinal functions in *** is well known that Fusarium mycotoxins will lead a breakdown of the normally impeccable epithelial barrier,resulting in the development of a "leaky" gut.H2 administration with different methods has been proved definitely potentials to prevent serious intestinal *** goal of this study is to investigate the roles of lactulose(LAC) and hydrogenrich water(HRW) in preventing intestinal dysfunction in piglets fed Fusarium mycotoxin-contaminated ***: A total of 24 female piglets were evenly assigned to 4 groups: negative control(NC) group,mycotoxincontaminated(MC) feed group,MC feed with LAC treatment(MC + LAC),and MC feed with HRW treatment(MC +HRW),*** in the NC group were fed uncontaminated control diet,while remaining piglets were fed Fusarium mycotoxin-contaminated *** the NC and MC groups,10 mL/kg body weight(BW) of hydrogen-free water(HFW) was orally administrated to piglets twice daily;while in the MC + LAC and MC + HRW groups,piglets were treated with the same dose of LAC solution(500 mg/kg BW) and HRW twice daily,*** d 25,serum was collected and used for biochemical *** tissues were sampled for morphological examination as well as relative genes and protein expression ***: Our data showed that Fusarium mycotoxins induced higher serum diamine oxidase(DAO) activities(P < 0.05),D-lactic acid levels(P < 0.01),and endotoxin status(P < 0.01),lower villus height(P < 0.01) and ratio of villus height to crypt depth(P < 0.05) in small intestine,greater apoptosis index and higher mRNA expression related to tight junctions(P < 0.05).In addition,the distribution and down-regulation of claudin-3(CLDN3) protein in the small intestinal was also *** expected,oral administrations of HRW and L

关键词： Fusarium mycotoxins Hydrogen-rich water Lactulose Piglets Small intestine

Rapid Hypoeutectic Growth Within a Highly Undercooled Liquid Under containerless Condition

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Chinese Physics Letters 2002年第4期19卷 584-587页

作者： Han Xiu-Jun yao wen-Jing Wei Bing-Bo Department of Applied Physics Northwestern Polytechnical University Xi'an 710072

Rapid hypoeutectic growth from a highly undercooled liquid was accomplished by containerless processing Ni-32%Sb hypoeutectic alloy in a 3m drop tube. The containerless state during the free fall of the droplet produces substantial undercooling up to 350K (0.24TL). The growth mechanism is found to transform from primary α-Ni dendrite plus lamellar eutectic to lamellar eutectic and finally to anomalous eutectic if droplet undercooling exceeds the two thresholds of 112K and 242K, respectively. Based on the current eutectic and dendritic growth models, the eutectic coupled zone is calculated and used to explain the growth mechanism transition. Calculations also indicate that the growth of α-Ni primary dendrite was mainly controlled by solute diffusion.

关键词： Drops

A machine learning surrogate modeling benchmark for temperature field reconstruction of heat source systems

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Science China(Information Sciences) 2023年第5期66卷 162-181页

作者： Xiaoqian CHEN Zhiqiang GONG Xiaoyu ZHAO Weien ZHOU wen yao Defense Innovation Institute Chinese Academy of Military Science

The temperature field reconstruction of heat source systems(TFR-HSS) with limited monitoring sensors in thermal management plays an important role in the real-time health detection systems of electronic equipment in engineering. However, prior methods with common interpolations usually cannot provide accurate reconstruction performance as required. In addition, no public dataset exists for the wide research of reconstruction methods to further boost reconstruction performance and engineering applications. To overcome this problem, this work develops a machine learning surrogate modeling benchmark for the TFRHSS task. First, the TFR-HSS task is mathematically modeled from a real-world engineering problem, and four types of computational modelings are constructed to transform the problem into discrete mapping ***, this work proposes a set of machine learning surrogate modeling methods, including general machine learning methods and deep learning methods, to advance the state-of-the-art methods over temperature field reconstruction. More importantly, this work develops a novel benchmark dataset, namely the temperature field reconstruction dataset(TFRD), to evaluate these machine learning surrogate modeling methods for the TFR-HSS task. Finally, a performance analysis of typical methods is given on the TFRD, which can serve as the baseline results on this benchmark.

关键词： temperature field reconstruction heat-source systems computational modeling temperature field reconstruction dataset machine learning surrogate modeling deep learning