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Maximum entropy mobility spectrum analysis for the type-ⅠWeyl semimetal TaAs

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Chinese Physics B 2022年第5期31卷 588-592页

作者： wen-Chong li ling-Xiao Zhao Hai-Jun Zhao Gen-Fu Chen Zhi-xiang Shi School of Physics and Key Laboratory of MEMS of the Ministry of Education Southeast UniversityNanjing 211189China Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing 100190China

Due to non-saturating magnetoresistance(MR)and the special compensation mechanism,the Weyl semimetal Ta As single crystal has attracted considerable attention in condensed matter ***,we use maximum entropy mobility spectrum analysis(MEMSA)to extract charge carrier information by fitting the experimentally measured longitudinal and transverse electric transport curves of Ta *** carrier types and the number of bands are obtained without any *** of the temperature dependence shows details of carrier property *** quantitative results explain the nonsaturated magnetoresistance and Hall sign change phenomena of TaAs.

关键词： Weyl semimetal mobility spectrum analysis magnetoresistance electrical transportation

Perturbative Quantum Chromodynamics Effects in Bc →PP Decays

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Chinese Physics Letters 2001年第4期18卷 498-500页

作者： GUO li-Bo DU dong-Sheng Department of Physics Wuhan UniversityWuhan 430072 Institute of High Energy Physics Chinese Academy of SciencesBeijing 100039

Using the leading order low energy effective Hamiltonian, we calculate Bc →PP (where P stands for pseudoscalar meson) decays induced by pure W-emission mechanisms. In order to estimate the hadronic matrix elements, we apply the perturbative quantum chromodynamics (PQCD) method proposed by Szczepaniak et al. [Phys. Lett. B 243 (1990) 287] and developed by Simma et al. [Phys. Lett. B 272 (1991) 395]. Comparing with predictions of other models, we find that the PQCD method is suitable for these decays and therefore the spectator ansatz seems questionable.

关键词： decay apply Hamiltonian

Non-parabolic effect for femtosecond laser-induced ultrafast electro-absorption in solids

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Chinese Physics B 2020年第1期29卷 446-451页

作者： li-Bo liu Hong-xiang Deng Xiao-Tao Zu Xiao-dong Yuan Wan-Guo Zheng School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China Research Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900China

A theoretical study for femtosecond laser-induced ultrafast electro-absorption of bulk solids is *** numerical results show that,in the case of low intensity of the pump laser where the interaction between the pump laser and solids is in the multi-photon regime,the energy band of solids can be approximately taken as a parabolic band and electro-absorption spectrums from the parabolic band and real band are nearly the ***,in the case of high intensity where the interaction is in the tunneling regime,spectrums from the parabolic band and real band are quite *** physical mechanism for the difference in the tunneling regime is *** find that the non-parabolic parts of the real energy band and Bragger scattering of electrons near the first Brillouin zone boundaries,which are neglected in previous studies,strongly influence the electro-absorption spectrum in the tunneling *** two physical processes cause the difference of *** theoretical results are in accordance with the experiment result.

关键词： ultrafast electro-absorption red-shift of absorption edge Bragger scattering effect multi-photon process

Cohomology of the Universal Enveloping Algebras of Certain Bigraded lie Algebras

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Acta Mathematica Sinica,English Series 2018年第10期34卷 1611-1625页

作者： li Nan ZHONG Hao ZHAO wen Huai SHEN School of Mathematical Sciences South China Normal University Guangzhou 510631 P. R. China Department of Mathematics Yanbian University Yanji 133000 P. R. China

Let p be an odd prime and q = 2（p- 1）. Up to total degree t - s 〈 max（（5p^3 ＋ 6p^2 ＋6p ＋4）q- 10,p^4q}, the generators of H^s,t（U（L））, the cohomology of the universal enveloping algebra of a bigraded lie algebra L, are determined and their convergence is also verified. Furthermore our results reveal that this cohomology satisfies an analogous Poindare duality property. This largely generalizes an earlier classical results due to J. P. May.

关键词： Steenrod algebra Hopf algebra lie algebra spectral sequence stable homotopy groups of sphere

Effect of Potassium on Ultrastructure of Maize Stalk Pith and Young Root and Their Relation to Stalk Rot Resistance

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Agricultural Sciences in China 2010年第10期9卷 1467-1474页

作者： li wen-juan HE Ping JIN Ji-yun Key Laboratory of Plant Nutrition and Nutrient Cycling Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China

To study the mechanism of potassium （K） application on improvement of maize resistance to stalk rot at cellular level, scanning electron microscope and transmission electron microscope were used to observe the effect of K on the ultrastructure of maize stalk pith tissue and young root tip cell influenced by K and pathogen. In K deficient treatment, parenchyma cells of stalk pith had abnormal structure, and the cell wall between upper and lower adjacent cell was damaged, resulting in the loss of connections between vascular cells and insufficient supporting capacity. However, an improved K nutrition helped to keep a quite tight arrangement of root cell with thick cell wall, and prevent the invasion of pathogen effectively. Moreover, K treated root cell had abundant golgi apparatus, which could excrete large amount of secretions to degrade mycelium. Papillary and highly electronic intensity dot were accumulated at the invading point to prevent the deveJopment of the mycelium. Improved K nutrition could increase the resistant ability of maize plant to stalk rot, through keeping cell structure stability, preventing the expansion of intracellular space to reduce the chances of pathogen invasions, and through reinforcing cell wall and formation of intercellular and intracellular material to restrict further development of pathogen in host cell.

关键词： potassium (K) maize stalk rot ultrastructure disease resistance

Design and application of microgrid operation control system based on IEC 61850

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Journal of Modern Power Systems and Clean Energy 2014年第3期2卷 256-263页

作者： wen LU Yangdong ZHAO Weixing li Hongwei DU School of Electrical Engineering and Automation Harbin Institute of Technology UniversityHarbin 150001China State Grid Electric Research Institute Nanjing 211000China

We consider the microgrid operation control technology including design of microgrid operation control system,MG control device and control *** pay much attention on microgrid operation control device which is core control *** order to solve the contradiction of quick speed about microgrid operation mode shift and slow speed about the management system,threelayers control architecture based on IEC61850 is designed and adaptive control strategy is used on MG operation control *** system has been applied in a distributed generation/energy storage power *** actual operation shows that the system can be effectively and flexibly connected to distribution network.

关键词： Distributed generator Microgrid Selfadaptive operation control V/f control IEC61850

Pharmacokinetics and Biodegradation Performance of a Hydroxypropyl Chitosan Derivative

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Journal of Ocean University of China 2015年第5期14卷 888-896页

作者： SHAO Kai HAN Baoqin dong wen song Fulai liU Weizhi liU Wanshun College of Marine life Science Ocean University of China

Hydroxypropyl chitosan(HP-chitosan) has been shown to have promising applications in a wide range of areas due to its biocompatibility, biodegradability and various biological activities, especially in the biomedical and pharmaceutical fields. However, it is not yet known about its pharmacokinetics and biodegradation performance, which are crucial for its clinical applications. In order to lay a foundation for its further applications and exploitations, here we carried out fluorescence intensity and GPC analyses to determine the pharmacokinetics mode of fluorescein isothiocyanate-labeled HP-chitosan(FITC-HP-chitosan) and its biodegradability. The results showed that after intraperitoneal administration at a dose of 10 mg per rat, FITC-HP-chitosan could be absorbed rapidly and distributed to liver, kidney and spleen through blood. It was indicated that FITC-HP-chitosan could be utilized effectively, and 88.47% of the FITC-HP-chitosan could be excreted by urine within 11 days with a molecular weight less than 10 k Da. Moreover, our data indicated that there was an obvious degradation process occurred in liver(lity and biodegradability, suggesting the potential applications of hydroxypropyl-modified chitosan as materials in drug delivery, tissue engineering and biomedical area.

关键词： hydroxypropyl chitosan fluorescein isothiocyanate pharmacokinetics biodegradation performance biomedicalmaterial

Dynamic Weapon Target Assignment Based on Intuitionistic Fuzzy Entropy of Discrete Particle Swarm

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China Communications 2017年第1期14卷 169-179页

作者： Yi Wang Jin li wenlong Huang Tong wen State Key Laboratory of Astronautic Dynamics Xi'an 7 10043 China Northwest University School of Information and Technology Xi'an 710127 China Air Defense and Antimissile Institute Air Force Engineering University Xi'an 710051 China

Aiming at the problems of convergence-slow and convergence-free of Discrete Particle Swarm Optimization Algorithm(DPSO) in solving large scale or complicated discrete problem, this article proposes Intuitionistic Fuzzy Entropy of Discrete Particle Swarm Optimization(IFDPSO) and makes it applied to Dynamic Weapon Target Assignment(WTA). First, the strategy of choosing intuitionistic fuzzy parameters of particle swarm is defined, making intuitionistic fuzzy entropy as a basic parameter for measure and velocity mutation. Second, through analyzing the defects of DPSO, an adjusting parameter for balancing two cognition, velocity mutation mechanism and position mutation strategy are designed, and then two sets of improved and derivative algorithms for IFDPSO are put forward, which ensures the IFDPSO possibly search as much as possible sub-optimal positions and its neighborhood and the algorithm ability of searching global optimal value in solving large scale 0-1 knapsack problem is intensified. Third, focusing on the problem of WTA, some parameters including dynamic parameter for shifting firepower and constraints are designed to solve the problems of weapon target assignment. In addition, WTA Optimization Model with time and resource constraints is finally set up, which also intensifies the algorithm ability of searching global and local best value in the solution of WTA problem. Finally, the superiority of IFDPSO is proved by several simulation experiments. Particularly, IFDPSO, IFDPSO1~IFDPSO3 are respectively effective in solving large scale, medium scale or strict constraint problems such as 0-1 knapsack problem and WTA problem.

关键词： intuitionistic fuzzy entropy discrete particle swarm optimization algorithm 0-1 knapsack problem weapon target assignment

Modulation of the Intensity of Nascent Tibetan Plateau Vortices by Atmospheric Quasi-Biweekly Oscillation

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Advances in Atmospheric Sciences 2018年第11期35卷 1347-1361页

作者： Lun li Renhe ZHANG Min wen Jianping DUAN State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Institute of Atmospheric Sciences Fudan UniversityShanghai 200433China Chinese Academy Science Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China Institute of Atmospheric Physics Chinese Academy ScienceBeijing 100029China

The modulation of the intensity of nascent Tibetan Plateau vortices(ITPV) by atmospheric quasi-biweekly oscillation(QBWO) is investigated based on final operational global analysis data from the National Centers for Environmental Prediction. The spatial and temporal distributions of the ITPV show distinct features of 10–20-day QBWO. The average ITPV is much higher in the positive phases than in the negative phases, and the number of strong TPVs is much larger in the former,with a peak that appears in phase 3. In addition, the maximum centers of the ITPV stretch eastward in the positive phases,indicating periodic variations in the locations where strong TPVs are generated. The large-scale circulations and related thermodynamic fields are discussed to investigate the mechanism by which the 10–20-day QBWO modulates the ITPV. The atmospheric circulations and heating fields of the 10–20-day QBWO have a major impact on the ITPV. In the positive QBWO phases, the anomalous convergence at 500 hPa and divergence at 200 hPa are conducive to ascending motion. In addition, the convergence centers of the water vapor and the atmospheric unstable stratification are found in the positive QBWO phases and move eastward. Correspondingly, condensational latent heat is released and shifts eastward with the heating centers located at 400 hPa, which favors a higher ITPV by depressing the isobaric surface at 500 hPa. All of the dynamic and thermodynamic conditions in the positive QBWO phases are conducive to the generation of stronger TPVs and their eastward expansion.

关键词： quasi-biweekly oscillation Tibetan Plateau vortex modulation