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Equivalent Characterization of Centralizers on B(H)

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Acta Mathematica Sinica,English Series 2016年第9期32卷 1113-1120页

作者： Wen Si XU Run Ling AN Jin Chuan HOU Department of Mathematics Taiyuan University of Technology Taiyuan 030024 P. R. China

Let H be a Hilbert space with dimH ≥2 and Z ∈ B（H） be an arbitrary but fixed operator. In this paper we show that an additive map （I）： B（H）→ B（H） satisfies Ф（AB） = Ф（A）B = AФ（B） for any A, B ∈ B（H） with AB = Z if and only if Ф（AB） = Ф（A）B = AФ（B）, A, B ∈ B（H）, that is, （I） is a centralizer. Similar results are obtained for Hilbert space nest algebras. In addition, we show that Ф（A2） = AФ（A） = Ф（A）A for any A ∈ B（H） with A2 = 0 if and only if Ф（A） = AФ（I） = Ф（I）A, A ∈ B（H）, and generalize main results in Linear Algebra and its Application, 450, 243-249 （2014） to infinite dimensional case. New equivalent characterization of centralizers on B（H） is obtained.

关键词： Centralizers full-centralized points von Neumann algebras nest algebras

Positional cloning of PmCH1357 reveals the origin and allelic variation of the Pm2 gene for powdery mildew resistance in wheat

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The Crop Journal 2019年第6期7卷 771-783页

作者： Fang Chen Haiyan Jia Xiaojun Zhang Linyi Qiao Xin Li Jun Zheng Huijuan Guo Carol Powers Liuling Yan Zhijian Chang College of Life Science Shanxi UniversityTaiyuan 030006ShanxiChina The shanxi Province Key Laboratory of Crop Genetics and Gene Improvement Institute of Crop ScienceShanxi Academy of Agricultural SciencesTaiyuan 030031ShanxiChina Department of Plant and Soil Sciences Oklahoma State UniversityStillwaterOK 74078USA The Applied Plant Genomics Laboratory of Crop Genomics and Bioinformatics Centre Nanjing Agricultural UniversityNanjing 210095JiangsuChina Institute of Wheat Research Shanxi Academy of Agricultural SciencesLinfen 041000ShanxiChina

Powdery mildew, caused by the biotrophic fungus Blumeria graminis f. sp. tritici(Bgt), is a prevalent disease in common wheat(Triticum aestivum L.) and causes serious yield losses worldwide. We used a map-based approach to clone the major broad-spectrum powdery mildew resistance gene Pm CH1357 from wheat breeding line CH1357. Pm CH1357 was mapped to a 526 kb region containing only Traes CS5 D01 G044600. The Traes CS5 D01 G044600 sequence of the susceptibility allele in Taichung 29(TC29) was identical to that in Chinese Spring, whereas the sequence of the resistance allele in CH1357 was identical to Pm2a previously cloned from the germplasm Ulka/*8Cc. The susceptibility allele in TC29 contained a 7 bp deletion in exon 1, resulting in loss of 856 of the 1277 amino acids in the predicted nucleotide-binding domain leucine-rich repeat containing Pm2a *** CH1357/Pm2a sequence was also isolated from the Chinese wheat landraces and cultivars that were previously reported to possess the resistance gene Pm2b, Pm2c,PmLX66, or PmND399. The Pm CH1357/Pm2a resistance allele was present in 10 of 495 accessions in core germplasm and contemporary cultivars from China and the USA. A newly developed diagnostic marker for the 7 bp In Del in the resistance gene can be used to eliminate the susceptibility allele in wheat breeding programs.

关键词： Map-based cloning Natural variation Bgt isolate E09 Triticum aestivum Molecular breeding

Structural, thermodynamics and elastic properties of Mg_(17)Al_(12), Al_2Y and Al_4Ba phases by first-principles calculations

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Journal of Central South University 2012年第6期19卷 1475-1481页

作者：黄志伟赵宇辉侯华赵宇宏牛晓峰韩培德 College of Materials Science and Engineering North University of China Department of Mechanical and Electronic Engineering Hebei College of Industry and Technology College of Materials Science and Engineering Taiyuan University of Technology

Structural stabilities, thermodynamics stabilities, elastic properties and electronic structures of Mgl7Al12, Al2Y and AlaBa phases were analyzed by first-principles calculations with Castep and Drool3 program based on the density functional theory. The calculated results of heat of formation indicate that AI2Y phase has the strongest alloying ability. The calculated thermodynamic properties show that the thermal stability of these compounds gradually increases in the order ofMgl7Al12, A12Y and Al4Ba phases. Y or Ba addition to the Mg-Al alloys could improve the heat resistance. The calculated bulk modulus B, shear modulus G, elastic modulus E and Poisson ratio v show that the adding Y or Ba to Mg-Al alloys could promote the brittleness and stiffness, and reduce tenacity and plasticity by forming Al4Ba and Al2Y phases. The calculated cohesive energy and density of state （DOS） show that Al2Y has the strongest structural stability, then AlaBa and finally Mg17Al12. The calculated electronic structures show that Al2Y has the strongest structure stability because of the strong ionic bonds and covalent bonds combined action.

关键词： Mg-Al alloys thermodynamics properties elastic properties electronic structure first-principles

Cavitation of a Submerged Jet at the Spherical Valve Plate/Cylinder Block Interface for Axial Piston Pump

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Chinese Journal of Mechanical Engineering 2020年第5期33卷 197-211页

作者： Bin Zhao Weiwei Guo Long Quan College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024China Transducers and Intelligent Control System of Ministry of Education and shanxi Province Taiyuan University of TechnologyTaiyuan 030024China The State Key Laboratory of Fluid Power&Mechatronic Systems Zhejiang UniversityHangzhou 310027China

The spherical valve plate/cylinder block pair has the advantages of strong overturning resistance and large bearing ***,the configurations of the unloading and pre-boosting triangular grooves on the spherical valve plate are different from those in the planar valve plate,resulting in special cavitation phenomenon on the spherical port plate *** order to study cavitation characteristics of spherical port plate pair,a dynamic CFD model of the piston pump including turbulence model,cavitation model and fluid compressibility is established.A detailed UDF compilation scheme is provided for modelling of the micron-sized spherical oil film mesh,which makes up for the lack of research on the meshing of the spherical oil *** this paper,using CFD simulation tools,from the perspectives of pressure field,velocity field and gas volume fraction change,a detailed analysis of the transient evolution of the submerged cavitation jet in a axial piston pump with spherical valve plate is carried *** study indicates the movement direction of the cavitation cloud cluster through the cloud image and the velocity vector direction of the observation *** sharp decrease of velocity and gas volume fraction indicates the collapse phenomenon of bubbles on the part wall *** discoveries verify the special erosion effect in case of the spherical valve plate/cylinder block *** submerged cavitation jet generated by the unloading triangular grooves distributed on the spherical valve plate not only cause denudation of the inner wall surface of the valve plate,but also cause strong impact and denudation on the lower surface of the cylinder ***,the direction of the unloading triangular groove was modified to extend the distance between it and the wall surface which can effectively alleviate the erosion effect.

关键词： Cavitation submerged jet Spherical valve plate/cylinder block pair Axial piston pump

Deposition of Ag Nanoparticles on Carbon Microspheres Surface：Evaluation of Structures,Electrochemical and Optical Properties

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Journal of Wuhan University of Technology(Materials Science) 2016年第4期31卷 743-749页

作者：杨维佳 HAO Yamin YAN Lingpeng 杨永珍陈永康 LIU Xuguang XU Bingshe Key Laboratory of lnterface Science and Engineering in Advanced Materials Taiyuan University of Technology Taiyuan 030024 China Research Center on Advanced Material Science and Technology Taiyuan University of Technology Taiyuan 030024 China College of Chemistry and Chemical Engineering Taiyuan University of Technology Taiyuan 030024 China

A hybrid material of carbon microspheres（CMSs） with Ag decoration（Ag/CMSs） was ***（3-hexylthiophene）：Ag/CMSs composite film was prepared by *** electron microscopy,transmission electron microscopy,Fourier transform infrared spectrometry,X-ray diffraction,thermogravimetric analysis and cyclic voltammetry were employed to analyze the morphologies,structures,thermal properties and energy levels of Ag/*** optical property of the composite films was characterized by ultraviolet-visible spectrophotometry and fluorescent *** results indicate that silver nanoparticles（AgNPs,d = 10-20 nm） are distributed on the surface of *** and HOMO energy levels of Ag/CMSs are-3.97 and-5.52 e V,below the vacuum energy level,respectively,indicating that it is feasible to use Ag/CMSs as an electron *** NPs are blended into the active layer to trigger localized surface plasmon resonance,and consequently enhance light *** coupling of surface plasmons and excitons increased the probability of exciton dissociation.

关键词： ultraviolet silver voltammetry plasmon visible consequently exciton dissociation blended localized

Influence of Modified Medical Stone on Behavior of Sulfur during Pyrolysis of Longma Coal

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China Petroleum Processing & Petrochemical Technology 2017年第1期19卷 81-91页

作者： Li Jingkuan Zhao Shuguang Wang Baofeng Jin Yan Zhang Jinjun Cheng Fangqin College of Electrical and Power Engineering Taiyuan University of Technology Taiyuan 030024 School of Chemistry & Material Science Shanxi Normal University Linfen 041004 Research Institute of Resources and Environment Engineering Shanxi University State Environmental Protection Key Laboratory of Efficient Utilization of Waste Coal Resources Taiyuan 030006

The influence of Co Mo P/medical stone and SO_4^(2-)/medical stone on sulfur behavior during the Longma coal pyrolysis was investigated in a fixed bed reactor. Moreover, the kinetics was also studied. It is found that adding SO_4^(2-)/medical stone was favorable to removal of volatile matter, while adding Co Mo P/medical stone could inhibit the emission of volatiles. Moreover, the results also showed that adding Co Mo P/medical stone made the total sulfur retention higher, while adding SO_4^(2-)/medical stone made the total sulfur retention lower. Adding modified medical stone was beneficial to removal of sulfate sulfur and pyritic sulfur, while it was beneficial to retaining organic sulfur in the residue. Furthermore, adding Co Mo P/medical stone and SO_4^(2-)/medical stone all could increase the emission of H_2S when the temperature was higher than 450℃. Judging from the kinetics study, it also can be known that addition of the natural minerals could result in a decrease of the pre-exponential factor and also change the apparent activation energy upon comparing the apparent activation energy and the pre-exponential factor of raw Longma coal at 435—537℃.

关键词： coal modifed medical stone sulfur behavior pyrolysis kinetics

A resilient trust management scheme for defending against reputation time-varying attacks based on BETA distribution

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Science China(Information Sciences) 2017年第4期60卷 60-70页

作者： Weidong FANG Wuxiong ZHANG Yang YANG Yang LIU Wei CHEN Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai Research Center for Wireless Communication School of Computer Science and Technology China University of Mining and Technology

Compared with the encryption and the authentication which can prevent the external attacks,the trust management schemes are the better approaches for defending against the internal attacks in wireless sensor network(WSN). The reputation time-varying(RTV) attacks are internal attacks. In the reputation timevarying attacks, the reputation value of nodes is manipulated to adjust dynamically by the compromised nodes or malicious attackers. Hence, these attacks have greater covert and invasive. In this paper, we propose a Timewindow-based Resilient Trust Management Scheme(TRTMS) to defend against the reputation time-varying attacks in wireless sensor network. In this scheme, based on BETA distribution, the behaviors of compromised nodes are analyzed for a period of time, and then the difference judgment and the trend analysis are utilized to identify the abnormality of nodes’ reputation value, meanwhile, the control factor Fc and the time window are introduced to verify and remove the compromised modes from the suspected malicious nodes, which refer to those nodes’ reputation value changes are caused by the wireless channel changes. The result of simulation shows that our proposed scheme can defend reputation time-varying attacks effectively and it is convenient to implement.

关键词： wireless sensor network(WSN) reputation time-varying attack trust value trust management time window

Improving Network Availability through Optimized Multipath Routing and Incremental Deployment Strategies

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Computers, Materials & Continua 2024年第7期80卷 427-448页

作者： Wei Zhang Haijun Geng Computer Application Teaching and Research Section China University of Labor RelationsBeijing100048China School of Automation and Software Engineering Shanxi UniversityTaiyuan030006China

Currently,distributed routing protocols are constrained by offering a single path between any pair of nodes,thereby limiting the potential throughput and overall network *** approach not only restricts the flow of data but also makes the network susceptible to failures in case the primary path is *** contrast,routing protocols that leverage multiple paths within the network offer a more resilient and efficient *** routing,as a fundamental concept,surpasses the limitations of traditional shortest path first *** not only redirects traffic to unused resources,effectively mitigating network congestion,but also ensures load balancing across the *** optimization significantly improves network utilization and boosts the overall performance,making it a widely recognized efficient method for enhancing network *** further strengthen network resilience against failures,we introduce a routing scheme known as Multiple Nodes with at least Two Choices(MNTC).This innovative approach aims to significantly enhance network availability by providing each node with at least two routing *** doing so,it not only reduces the dependency on a single path but also creates redundant paths that can be utilized in case of failures,thereby enhancing the overall resilience of the *** ensure the optimal placement of nodes,we propose three incremental deployment *** algorithms carefully select the most suitable set of nodes for deployment,taking into account various factors such as node connectivity,traffic patterns,and network *** deployingMNTCon a carefully chosen set of nodes,we can significantly enhance network reliability without the need for a complete overhaul of the existing *** have conducted extensive evaluations of MNTC in diverse topological spaces,demonstrating its effectiveness in maintaining high network availability with minimal path *** results are impressive,sh

关键词： Multipath routing network availability incremental deployment schemes genetic algorithm

Effect of artesunate supplementation on bacterial translocation and dysbiosis of gut microbiota in rats with liver cirrhosis

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World Journal of Gastroenterology 2016年第10期22卷 2949-2959页

作者： Yun-Xia Chen Li-Na Lai Hui-Ying Zhang Yang-Hui Bi Li Meng Xu-Jiong Li Xiao-Xia Tian Li-Min Wang Yi-Min Fan Zhong-Fu Zhao De-Wu Han Cheng Ji Department of Microbiology Changzhi Medical College Department of Pharmacology Changzhi Medical College Department of Pathophysiology Changzhi Medical College Department of Physiology Changzhi Medical College Functional Integrative Laboratory Department of PathophysiologyChangzhi Medical College Institute of Hepatology Changzhi Medical College Institute of Hepatology Shanxi Medical University USC Research Center for Liver Disease Department of MedicineUniversity of Southern California

AIM: To evaluate the effect of artesunate(AS) supplementation on bacterial translocation(BT) and gut microbiota in a rat model of liver cirrhosis. METHODS: Fifty-four male Sprague-Dawley rats were randomly divided into a normal control group(N), a liver cirrhosis group(M) and a liver cirrhosis group intervened with AS(MA). Each group was sampled at 4, 6 and 8 wk. Liver cirrhosis was induced by injection of carbon tetrachloride(CCl4), intragastric administration of 10% ethanol, and feeding a high fat diet. Rats in the MA group were intragastrically administered with AS(25 mg/kg body weight, once daily). Injuries of the liver and intestinal mucosa were assessed by hematoxylineosin or Masson's trichrome staining. Liver index was calculated as a ratio of the organ weight(g) to body weight(g). The gut microbiota was examined by automated ribosomal intergenic-spacer analysis of fecal DNA. BT was assessed by standard microbiological techniques in the blood, mesenteric lymph nodes(MLNs), liver, spleen, and kidney. RESULTS: Compared to group N, the body weight was reduced significantly in groups M and MA due to the development of liver cirrhosis over the period of 8 wk. The body weight was higher in group MA than in group M. The liver indices were significantly elevated at 4, 6 and 8 wk in groups M and MA compared to group N. AS supplementation partially decreased the liver indices in group MA. Marked histopathologic changes in the liver and small intestinal mucosa in group M were observed, which were alleviated in group MA. Levels of pro-inflammatory interleukin-6 and tumor necrosis factor-α were significantly elevated at 8 wk in ileal homogenates in group M compared to group N, which were decreased after AS supplementation in group MA. The dysbiosis of gut microbiota indicated by the mean diversity(Shannon index) and mean similarity(Sorenson index) was severe as the liver cirrhosis developed, and AS supplementation had an apparent intervention effect on the dysbiosis of gu

关键词： Hepatic cirrhosis Gut microbiota Bacterial translocation Artesunate Intervention