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Plant Diversity 2019年第5期41卷 323-329页

作者： Lin-Lin Wang zhi-Qiang Zhang Yong-ping Yang yuan-Wen Duan Key Laboratory for Plant Diversity and Biogeography of East Asia Germplasm Bank of Wild SpeciesInstitute of Tibetan Plateau Research at KunmingKunming Institute of BotanyChinese Academy of SciencesKunmingYunnan650201China University of the Chinese Academy of Sciences Beijing100049China Laboratory of Ecology and Evolutionary Biology Yunnan UniversityKunmingYunnan650091China

Dasiphora fruticosa comprises male,female and hermaphrodite plants,which are distributed sympatrically in some populations on the Qinghai-Tibet *** explore what governs the coexistence of these three sexual phenotypes,we investigated the DNA contents,pollen and ovule production,pollen deposition,and performed hand-pollination in both hermaphroditic and dioecious individuals of *** cytometry confirmed that the DNA content of males and females were almost twice as much as that of the *** and female flowers produced more pollen grains and ovules than hermaphroditic ***-pollinated treatments showed that unisexual flowers were sterile in one sexual function and bisexual flowers were fertile for both functions,but no sterile seeds were produced between unisexual and bisexual *** findings imply that polyploidy is related to gender dimorphism,and both are likely to play a strong role in the coexistence of two cryptic biological species of ***(low ploidy hermaphroditic species and high ploidy dioecious species)in the Qinghai-Tibet Plateau.

关键词： Gender polymorphism Dioecy Dasiphora fruticosa Polyploidy Reproductive isolation

Catalytical oxidation of styrene by molecularly imprinted polymer with phenylacetic acid as template and hemin as co-monomer

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Chinese Chemical Letters 2007年第8期18卷 981-984页

作者： Jun Wang zhi Yong Chen Mei ping Zhao yuan Zong Li The Key Laboratory of Bioorganic Chemistry and Molecular Engineering College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

This letter used the molecular imprinting technology to build up the microenvironment around co-monomer bemin to mimic the cytochrome P450 catalyzing the epoxidation of styrene. The results showed that the conversion rates of products were obviously enhanced by molecularly imprinted polymers, compared to free heroin solution, using three kinds of oxidants. The used axial ligand in polymers synthesis also improved the total conversion rates.

关键词： Molecularly imprinted polymers Enzyme mimic Cytochrome P450 Styrene Epoxidation

Surface metallization of PTFE and PTFE composites by ion implantation for low-background electronic substrates in rare-event detection experiments

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Nuclear Science and Techniques 2022年第7期33卷 37-47页

作者： Shao-Jun Zhang yuan-yuan Liu Sha-Sha Lv Jian-ping Cheng Bin Liao Pan Pang zhi Deng Li He College of Nuclear Science and Technology Beijing Normal UniversityJoint Laboratory of Jinping Ultra-low Radiation Background Measurement of Ministry of Ecology and Environment Beijing Normal UniversityKey Laboratory of Beam Technology of Ministry of EducationBeijing Normal UniversityBeijing100875China Beijing Radiation Center Beijing100875China Department of Engineering Physics Key Laboratory of Particle and Radiation Imaging of Ministry of EducationTsinghua UniversityBeijing100084China Joint Research Center Nuctech Company LimitedBeijing100084China

Polytetrafluoroethylene(PTFE)is a low-background polymer that is applied to several applications in rare-event detection and underground low-background ***-based electronic substrates are important for reducing the detection limit of high-purity germanium detectors and scintillator calorimeters,which are widely applied in dark matter and 0υββdetection *** traditional adhesive bonding method between PTFE and copper is not conducive to working in liquid nitrogen and extremely low-temperature *** avoid adhesive bonding,PTFE must be processed for surface metallization owing to the mismatch between the PTFE and copper conductive ***-background PTFE matrix composites(m-PTFE)were selected to improve the electrical and mechanical properties of PTFE by introducing SiO_(2)/TiO_(2) *** microstructures,surface elements,and electrical properties of PTFE and m-PTFE were characterized and analyzed following ion *** and m-PTFE surfaces were found to be broken,degraded,and cross-linked by ion implantation,resulting in C=C conjugated double bonds,increased surface energy,and increased surface ***,the surface roughness,bond strength,and conjugated double bonds of m-PTFE were significantly more intense than those of ***,the interface bonding theory between PTFE and the metal copper foil was analyzed using the direct metallization ***,the peel strength of the optimized electronic substrates was higher than that of the industrial standard at extremely low temperatures,while maintaining excellent electrical properties.

关键词： Surface modification Polytetrafluoroethylene Ion implantation Surface metallization Low temperature resistance

Short-Time Dynamics of the Random n-Vector Model

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Communications in Theoretical Physics 2001年第11期36卷 611-616页

作者： CHEN yuan LI zhi-Bing FANG Hai HE Shun-Shan SITU Shu-ping Department of Physics Guangzhou UniversityGuangzhou 510405China Department of PhysicsZhongshan UniversityGuangzhou 510275China Department of PhysicsZhongshan UniversityGuangzhou 510275China Department of PhysicsZhongshan UniversityGuangzhou 510275China Department of PhysicsZhongshan UniversityGuangzhou 510275China

Short-time critical behavior of the random n-vector model is studied by the theoretic renormalization-group *** scaling laws are studied in a frame of the expansion in e = 4 - d for n ≠ 1 and for n = *** d ＜ 4,the initial slip exponents θ′ for the order parameter and θ for the response function are calculated up to the second order in e ＝ 4 - d for n ≠ 1 and for n ＝ 1 at the random fixed point *** results show that the random impurities exert a strong influence on the short-time dynamics for d ＜ 4 and n ＜ nc.

关键词： n-vector model,short-time critical dynamics,quenched impurities,initial slip exponent

FK506 contributes to peripheral nerve regeneration by inhibiting neuroinflammatory responses and promoting neuron survival

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Neural Regeneration Research 2025年第7期20卷 2108-2115页

作者： Yuhui Kou Zongxue Jin Yusong yuan Bo Ma Wenyong Xie Na Han Department of Trauma and Orthopedics Peking University People’s HospitalBeijingChina National Center for Trauma Medicine Peking University People’s HospitalBeijingChina Key Laboratory of Trauma and Neural Regeneration(Peking University) Ministry of EducationBeijingChina Trauma Medicine Center Peking University People’s HospitalBeijingChina Department of Orthopedics China-Japan Friendship HospitalBeijingChina

FK506(Tacrolimus)is a systemic immunosuppressant approved by the *** and Drug ***506 has been shown to promote peripheral nerve regeneration,however,its precise mechanism of action and its pathways remain *** this study,we established a rat model of sciatic nerve injury and found that FK506 improved the morphology of the injured sciatic nerve,increased the numbers of motor and sensory neurons,reduced inflammatory responses,markedly improved the conduction function of the injured nerve,and promoted motor function *** findings suggest that FK506 promotes peripheral nerve structure recovery and functional regeneration by reducing the intensity of inflammation after neuronal injury and increasing the number of surviving neurons.

关键词： FK506 inflammation motor neurons nerve regeneration neuron peripheral nerve injury sensory neurons

Prediction of novel layered indium halide superconductors

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Chinese Physics B 2024年第10期33卷 388-393页

作者： zhi-Hong yuan Jing-Jing Meng Rui Liu Peng-Yu Zheng zhi-ping Yin School of Physics&Astronomy and Center for Advanced Quantum Studies Beijing Normal UniversityBeijing 100875China School of Physics and Information Engineering Shanxi Normal UniversityTaiyuan 030031China Key Laboratory of Multiscale Spin Physics(Ministry of Education) Beijing Normal UniversityBeijing 100875China

We design two new layered indium halide compounds LaOInF_(2)and LaOInCl_(2)by means of first-principles calculations and evolutionary crystal structure *** find both compounds crystallize in a tetragonal structure with P4/nmm space group and have indirect band gaps of 2.58 eV and 3.21 eV,*** substituting O with F,both of them become metallic and superconducting at low *** F-doping leads to strong electron-phonon coupling in the low-energy acoustic phonon modes which is mainly responsible for the induced *** total electron-phonon coupling strength are 1.86 and 1.48,while the superconducting transition temperature(T_(c))are about 7.2 K and 6.5 K with 10%and 5%F doping for LaOInF_(2)and LaOInCl_(2),respectively.

关键词： superconductor LaOInF_(2) LaOInCl_(2) electron-phonon coupling

Co/Co_(7)Fe_(3)heterostructures with controllable alloying degree on carbon spheres as bifunctional electrocatalyst forrechargeable zinc-air batteries

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 476-487页

作者： Junkang Chen Yongyue Zhuang Yanxin Qiao Yu Zhang Aihua yuan Hu Zhou School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Exploring efficient and nonprecious metal electrocatalysts of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is crucial for developing rechargeable zinc-air batteries(ZABs).Herein,an alloying-degree control strategy was employed to fabricate nitrogen-doped carbon sphere(NCS)decorated with dual-phase Co/Co_(7)Fe_(3)heterojunctions(CoFe@NCS).The phase composition of materials has been adjusted by controlling the alloying *** optimal CoFe_(0.08)@NCS electrocatalyst displays a half-wave potential of 0.80 V for ORR and an overpotential of 283 mV at 10 mA·cm^(-2)for OER in an alkaline *** intriguing bifunctional electrocatalytic activity and durability is attributed to the hierarchically porous structure and interfacial electron coupling of highly-active Co_(7)Fe_(3)alloy and metallic Co *** the CoFe_(0.08)@NCS material is used as air-cathode catalyst of rechargeable liquid-state zinc-air battery(ZAB),the device shows a high peak power-density(157 mW·cm^(-2))and maintains a stable voltage gap over 150 h,outperforming those of the benchmark(Pt/C+RuO_(2))-based *** particular,the as-fabricated solid-state flexible ZAB delivers a reliable compatibility under different bending *** work provides a promising strategy to develop metal/alloy-based electrocatalysts for the application in renewable energy conversion technologies.

关键词： bifunctional electrocatalysts oxygen reduction reaction oxygen evolution reaction zinc-air battery metal/alloy carbon sphere

Microstructure and antibacterial property of stainless steel implanted by Cu ions

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中国有色金属学会会刊：英文版 2004年第z1期14卷 328-331页

作者： XU Bo-fan NI Hong-wei XIONG ping-yuan XIONG Juan DAN zhi-gang School of Material and Metallurgy Wuhan University of Science and Technology Wuhan 430081 China School of Material and Metallurgy Wuhan University of Science and Technology Wuhan 430081 China School of Medicine Science Wuhan 430081 China School of Material and Metallurgy Wuhan University of Science and Technology Wuhan 430081 China School of Material and Metallurgy Wuhan University of Science and Technology Wuhan 430081 China

Copper ions were implanted into AISI 304 austenitic stainless steel by metal vapor vacuum are (MEVVA) with 60 - 100 keV energy and a dose range (0.2 - 5.0) × 1017 cm-2. Then Cu-implanted stainless steel was treated by a special antibacterial treatment. Antibacterial rates of Cu-implanted stainless steel, Cu-implanted stainless steel with special antibacterial treatment and un-implanted stainless steel were obtained by agar plate method. Phase composition in the implanted layer was analyzed by glancing X-ray diffraction (GXRD). Microstructure of antibacterial stainless steel was observed with transmission electron microscopy (TEM), and changes of the bacterium appearance after 24 h antibacterial action on the surface of un-implanted and Cu-implanted stainless steel with antibacterial treatment were observed with bio-TEM respectively. The results show that stainless steel obtains antibacterial property against E. coli when the Cu ions dose approaches to the saturated one. A suitable amount of Cu-rich phase uniformly disperses on the surface of Cu-implanted stainless steel that is treated by the special antibacterial treatment. The Cu-rich phase naked on the surface has a function of damage to pericellular membrane and cell wall,the pericellular membrane is thickened and the karyon degraded, and finally, bacteria die. Cu-rich phase naked on the surface endows stainless steel with best antibacterial property.

关键词： stainless steel copper ion implantation antibacterial property

Substrate effects on spin relaxation in two-dimensional Dirac materials with strong spin-orbit coupling

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npj Computational Materials 2023年第1期9卷 1880-1889页

作者： Junqing Xu yuan ping Department of Chemistry and Biochemistry University of CaliforniaSanta CruzCA 95064USA

Understanding substrate effects on spin dynamics and relaxation is of key importance for spin-based information ***, the key factors that determine such effects, in particular for materials with strong spin-orbit coupling (SOC), have notbeen well understood. Here we performed first-principles real-time density-matrix dynamics simulations with SOC and the electron-phonon and electron-impurity scattering for spin lifetimes (τ_(s)) of supported/free-standing germanene, a prototypical strong SOC 2DDirac material. We show that the effects of different substrates on τ_(s) can surprisingly differ by two orders of magnitude. We find thatsubstrate effects on τs are closely related to substrate-induced modifications of the SOC-field anisotropy, which changes the spin-flip scattering matrix elements. We propose a new electronic quantity, named spin-flip angle θ↑↓, to characterize spin relaxationthrough intervalley spin-flip scattering. We find that T_(s)^(-1) is approximately proportional to the averaged value of sin^(2)( θ↑↓/2 ) , whichserves as a guiding parameter of controlling spin relaxation.

关键词： material relaxation coupling

Nanophotonics in China： Overviews and highlights

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Frontiers of physics 2012年第6期7卷 601-631页

作者： zhi-yuan Li Laboratory of Optical Physics Institute of PhysicsChinese Academy of SciencesP.O.Box 603Beijing 100190China

The major purpose of this paper is to present a brief overview of the history and the current status of nanophotonics research in China, and to highlight some research results in the past years made by the Chinese nanophotonics communities. I will first briefly introduce the principles of nanophotonics and several of its major disciplines including photonic crystals, plasmonics and metamaterials, and related artificial acoustic structures. Then I will highlight some major progresses made by Chinese research groups in these areas with the selection made merely based on my personal taste. The aim is to let these results better known and appreciated by researchers in the Chinese communities of nanophotonics and related areas, and provide better opportunities of researchers in different areas to have more communications. I also hope that this brief introduction will help to make a better bridge to connect Chinese nanophotonics communities with the broader communities in the world.

关键词： nanophotonics photonic crystals plasmonics metamaterials phononic crystals