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Energy and centrality dependence of light nuclei production in relativistic heavy-ion collisions

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Nuclear Science and Techniques 2022年第4期33卷 62-71页

作者： Li-lin zhu Bo Wang Meng Wang Hua Zheng Department of Physics Sichuan UniversityChengdu 610064China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China

We study the energy and centrality dependence of deuteron and triton(helium-3)production in relativistic heavy-ion collisions at the BNL Relativistic Heavy Ion Collider(RHIC)and CERN Large Hadron Collider(LHC)using the Tsallis distribution,blast-wave(BW)model,and stationary Fokker-Planck(FP)*** study shows that good agreement can be reached between the fitting results from the stationary FP solution and the experimental data for Au+Au collisions from the beam energy scan(BES)program of RHIC at√SNN=7.7,11.5,14.5,19.6,27,39,62.4,and 200 GeV and for Pb+Pb collisions at√SNN=2.76 *** Tsallis distribution and BW model can reasonably describe the deuteron and triton(helium-3)trans verse momentum spectra obtained at RHIC and LHC.A more comprehensive comparison among the three methods suggests that the stationary FP solution is a sensible method,which is able to describe the energy dependence of the light nuclei yield ratio N_(t)N_(p)/N_(d)^(2) and provide a coherent description of deuteron and triton(helium-3)production for all centralities and various colliding energies at RHIC and LHC.

关键词： Light nucleiproduction Heavy-ioncollisions Tsallis distribution Blast-wavemodel Fokker–Planck solution

Traveling wave solutions for a diffusive predator-prey model with predator saturation and competition

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International Journal of Biomathematics 2017年第6期10卷 231-253页

作者： lin zhu Shi-Liang Wu School of Mathematics and Statistics Xidian University Xi'an Shanxi 710071 P. R. China

The purpose of this paper is to study the traveling wave solutions of a diffusive predator- prey model with predator saturation and competition functional response. The system admits three equilibria： a zero equilibrium E0, a boundary equilibrium E1 and a posi- tive equilibrium E. under some conditions. We establish the existence of two types of traveling wave solutions which connect E0 and E. and E1 and E., respectively. Our main arguments are based on a simplified shooting method, a sandwich method and constructions of appropriate Lyapunov functions. Our particular interest is to investi- gate the oscillation of both types of traveling wave solutions when they approach the positive equilibrium.

关键词： Diffusive predator prey model traveling wave solution shooting argument Wazewski's set LaSalle's invariance principle.

Novel Photodetectors Based on Double-Walled Carbon Nanotube Film/TiO2 Nanotube Array Heterodimensional Contacts

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Nano Research 2011年第9期4卷 901-907页

作者： Mingjie Yang Jia-lin zhu Wei Liu Jia-lin Sun Department of Physics and State Key Lab of Low-Dimensional Quantum Physics Tsinghua University Beijing 100084 China Laboratory of Advanced Materials Department of Material Science and Engineering Tsinghua University Beijing 100084 China

A new kind of photodetector based on a double-walled carbon nanotube （DWCNT） film and a TiO2 nanotube array with hetrodimensional non-ohmic contacts has been fabricated. Due to the dimensionality difference effect, the DWCNT film/TiO2 nanotube array photodetector exhibits a much higher photocurrent-to-dark current ratio and photoresponse relative to an Au film/TiO2 nanotube array device, even at small bias voltage. The photocurrent-to-dark current ratio reached four orders of magnitude and a high photoresponse of 2467 A/W was found upon irradiation at 340 nm. Furthermore, the photosensitive regions could be extended into the visible range. The photocurrent-to-dark current ratio reached approximately three orders of magnitude upon irradiation at 532 nm, where the photon energy is much lower than the band gap of TiO2.

关键词： Photodetectors double-wailed carbon nanotube (DWCNT) films TiO2 nanotube arrays heterodimensional contacts

Variable-K double trenches SOI LDMOS with high-concentration P-pillar

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Chinese Physics B 2020年第5期29卷 498-503页

作者： Lijuan Wu lin zhu Xing Chen The Hunan Provincial Key Laboratory of Flexible Electronic Materials Genome Engineering School of Physics&Electronic ScienceChangsha University of Science&TechnologyChangsha 410114China

A variable-K trenches silicon-on-insulator(SOI)lateral diffused metal-oxide-semiconductor field-effect transistor(MOSFET)with a double conductive channel is proposed based on the enhancement of low dielectric constant media to electric *** device features variable-K dielectric double trenches and a P-pillar between the trenches(VK DT-P LDMOS).The low-K dielectric layer on the surface increases electric field of *** a variable-K material introduces a new electric field peak to the drift region,so as to optimize electric field inside the *** of the high-concentration vertical P-pillar between the two trenches effectively increases doping concentration of the drift region and maintains charge balance inside ***,breakdown voltage(BV)of the device is *** double conductive channels provide two current paths that significantly reduce specific on-resistance(Ron,sp).Simulation results demonstrate that a 17-μm-length device can achieve a BV of 554 V and a low on-resistance of 13.12 mΩ·cm^*** Ron,sp of VK DT-P LDMOS is reduced by 78.9%compared with the conventional structure.

关键词： variable-K(VK) trench technology specific on-resistance(Ron,sp) breakdown voltage(BV)

Predicting the D_(s)(*)D_(s)(*)bound states as the partners of X(3872)

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Science Bulletin 2021年第13期66卷 1288-1295,M0003,M0004页

作者： Lu Meng Bo Wang Shi-lin zhu Ruhr-Universität Bochum Fakultät für Physik und AstronomieInstitut für Theoretische Physik IID-44780 BochumGermany Center of High Energy Physics Peking UniversityBeijing 100871China School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China

In this work,we investigate the SU(3)flavor symmetry,heavy quark spin symmetry and their breaking effects in the di-meson *** prove the existence of the[D_(s)(*)D_(s)(*)]^(0++),[D_(s)(*)D_(s)(*)]^(1++),and[D_(s)(*)D_(s)(*)]^(1++)bound states as the consequence of two prerequisites in the SU(3)flavor symmetry and heavy quark spin *** first prerequisite,the X(3872)as the weakly D*D=DD*bound state is supported by its mass and decay branching *** second prerequisite,the existence of the DsDs[D_(s)(*)D_(s)(*)]^(0++)bound state is supported by the lattice QCD calculation and the observation of X_(c0)(3930)by the LHCb *** hope the future experimental analyses can search for these bound states in the B→[D_(s)(*)D_(s)(*)]h processes(h denotes the light hadrons).The[D_(s)(*)D_(s)(*)]^(0++)bound state is also expected to be reconstructed in the J/ψФinal state in the B→//ψФK decay.

关键词： SU(3)flavor symmetry Hadronic molecule Xe3872T Tetraquark

Copper-Catalyzed Carbotrifluoromethylation of Unactivated Alkenes Driven by Trifluoromethylation of Alkyl Radicals

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Chinese Journal of Chemistry 2019年第5期37卷 452-456页

作者： Zhenzhen Zhang lin zhu Chaozhong Li Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China School of Materials and Chemical Engineering Ningbo University of Technology No. 201 Fenghua Rood Ningbo Zhejiang 315211 China

Summary of main observation and conclusion We report herein an unprecedented protocol for radical carbotrifluoromethylation of unactivated alkenes. With Cu(OTf)2 as the catalyst, the reaction of unactivated alkenes, TMSCF3 and activated alkyl chlorides at room temperature provides the corresponding carbotrifluoromethylation products in satisfactory yields. Directed by trifluoromethylation of alkyl radicals, the method exhibits an excellent regioselectivity that is opposite to those driven by CF3 radical addition.

关键词： Summary report addition

X（1835）： A Possible Baryonium？

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Communications in Theoretical Physics 2006年第2X期46卷 291-293页

作者： zhu Shi-lin GAO Chong-Shou Department of Physics Peking University Beijing 100871 China Research Center for Nuclear Physics Osaka University Japan

We point out that the large pp^- coupling of X（1835） and the suppression of the three-body strange final states strongly indicate that X（1835） may be a pp^- baryonium. We also point out that the branching ratio of X（1835） →ηππ should be bigger than that of X（1835） →η′ππ. We suggest BES search X（1835） in the ηππ channel Finally, X（1835） may be used a tetraquark generator if X（1835） is really established as a baryonium state.

关键词： baryonium new hadron states

Three-Qubit Entanglement Sudden Death

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Communications in Theoretical Physics 2008年第6期49卷 1443-1448页

作者： GE Min zhu lin-Fan QIU Liang Hefei National Laboratory for Physical Sciences at Microscale Department of Modern Physics University of Science and Technology of China Hefei 230026 China Department of Modern Physics University of Science and Technology of China Hefei 230026 China

We study entanglement dynamics of three-qubit system via negativity. Three atoms A, B, and C interact isolatedly with their own Jaynes-Cummings cavities a, b, and c. Aa system is prepared entangled with Bb and Cc, however, their mutual isolations forbid Aa interacting with system Bb and Cc. It is the same for system Bb and Cc. We show entanglement evolution of different three-qubit systems ABC, abc, Abc, and aBC and find entanglement sudden death effect.

关键词： entanglement sudden death J-C models

Highly dispersed Mn_2O_3 microspheres:Facile solvothermal synthesis and their application as Li-ion battery anodes

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Particuology 2015年第5期13卷 89-94页

作者： Jianfei Yu lin zhu Cheng Fan Cheng Zan ling Hu Shuhui Yang Qiang Zhang Wancheng zhu lin Shi Fei Wei Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua University Department of Chemical Engineering Qufu Normal University State Key Laboratory of Enhanced Oil Recovery Research Institute of Petroleum Exploration & DevelopmentChina National Petroleum Corporation Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Thermal EngineeringTsinghua University

Nanostructured transition metal oxides are promising alternative anodes for lithium ion batteries. Li-ion storage performance is expected to improve if high packing density energy particles are available. Herein, Mn2O3 microspheres with a ca. 18 μm diameter and a tapped density of 1.33 g/cm3 were synthesized by a facile solvothermal-thermal coversion route. Spherical MnCO3 precursors were obtained through solvotbermal treatment and they decomposed and converted into Mn2O3 microspheres at an annealing temperature of 700℃. The Mn2O3 microspheres consisted of Mn2O3 nanoparticles with an average 40 nm diameter. These porous Mn2O3 microspheres allow good electrolyte penetration and provide an ion buffer reservoir to ensure a constant electrolyte supply. The Mn2O3 microspheres have reversible capacities of 590 and 320 mAh/g at 50 and 400 mA/g, respectively. We thus report an efficient route for the fabrication of energy particles for advanced energy storage.

关键词： Mn2O3 MicrospheresLi-ion batteries Solvothermal synthesis Nanostructures