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Non-centrosymmetric topological phase probed by non-linear Hall effect

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National Science Review 2024年第6期11卷 180-188页

作者： Naizhou Wang Jing-Yang You Aifeng Wang Xiaoyuan Zhou Zhaowei Zhang Shen Lai Yuan-Ping Feng Hsin Lin Guoqing Chang Wei-bo Gao Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University Department of Physics National University of Singapore Low Temperature Physics Laboratory College of Physics and Center for Quantum Materials and Devices Chongqing University Centre for Advanced 2D Materials National University of Singapore Institute of Physics Academia Sinica The Photonics Institute and Centre for Disruptive Photonic Technologies Nanyang Technological University

Non-centrosymmetric topological material has atracted intense atention due to its superior characteristics as compared with the centrosymmetric one, although probing the local quantum geometry in non-centrosymmetric topological material remains challenging. The non-linear Hall（NLH） effect provides an ideal tool to investigate the local quantum geometry. Here, we report a non-centrosymmetric topological phase in ZrTe5, probed by using the NLH effect. The angle-resolved and temperature-dependent NLH measurement reveals the inversion and ab-plane mirror symmetries breaking at <30 K, consistently with our theoretical calculation. Our findings identify a new non-centrosymmetric phase of ZrTe5and provide a platform to probe and control local quantum geometry via crystal symmetries.

关键词： non-linear Hall effect topological insulator ZrTe5

p-wave resonances in the exponential cosine screened Coulomb potential

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Communications in Theoretical Physics 2024年第7期76卷 105-113页

作者： Yuan-Cheng Wang Li Guang Jiao Aihua Liu Yew Kam Ho Stephan Fritzsche College of Physical Science and Technology Shenyang Normal UniversityShenyang 110034China College of Physics Jilin UniversityChangchun 130012China Helmholtz-Institut Jena D-07743 JenaGermany GSI Helmholtzzentrum fur Schwerionenforschung GmbH D-64291 DarmstadtGermany Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China Institute of Atomic and Molecular Sciences Academia SinicaTaipei 10617TaiwanChina

We perform benchmark calculations of the p-wave resonances in the exponentially cosine screened Coulomb potential using the uniform complex-scaling generalized pseudo-spectral *** present results show significant improvement in calculation accuracy compared to previous predictions and correct the misidentification of resonance electron configuration in previous *** is found that the resonance states approximately follow an n^(2)-scaling law which is similar to the bound *** birth of a new resonance would distort the trajectory of an adjacent higher-lying resonance.

关键词： complex-scaling method shape resonance generalized pseudospectral method exponential cosine screened Coulomb potential

SOLUBLE POLYACETYLENE OBTAINED WITH RARE-EARTH CATALYST AND SOME ASPECTS OF POLYMERIZATION MECHANISM

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Chinese Journal of Polymer Science 1987年第3期5卷 221-227页

作者：胡孝东王佛松赵晓江颜德岳 Department of Applied Chemistry Shanghai Jiaotong University Changchun Institute of Applied Chemistry academia sinica changchum

Soluble polyacetylene （PA） with well--defined nature has been synthesized with catalyst system Nd（i-OPr）3/AIR3 （R=C2H5-, i-C4H9-） and characterized by IR, Raman and ESR Spectra etc. Number average molecular weight of the soluble specimen were determined by VPO to be about 500g/mol. or lower. The IR and NMR spectra and end group analysis of' the soluble polyacetylene fully demonstrate that polymerization of acetylene with rare-earth catalyst is realized through monomer insertion between the transition metal-carbon bond.

关键词： Soluble polyacetylene Rare Earth Catalyst

THIRD ORDER NONLINEAR OPTICAL PROPERTIES OF PERNIGRANILINE SOLUTION IN CONCENTRATED SULFURIC ACID

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Chinese Journal of Polymer Science 1996年第1期14卷 80-85页

作者：万梅香李明米辛姜谦叶佩弦 Institute of Chemistry Academia Sinica Beijing 100080 Institute of Physics Academia Sinica Beijing 100080

The fully oxidized state of polyaniline (PANI), pernigraniline (PN), was synthesized by oxidation of the emeraldine base form of PAM dissolved in NMP solvent with m-chloroperoxybenzoic acid. The resulted PN was characterized by FTIR and UV-Visible spectra. The third-order nonlinear optical properties of PN in concentrated sulfuric acid (PN/H2SO4) were measured by a degenerated four wave mixing (DFWM) method. The results obtained suggest that the soliton-pair intermediate state associated with the degenerated state does not play a major role in the third order nonlinear optical properties of PANI.

关键词： polyaniline pernigraniline degenerated four waves mixing (DFWM) third-order nonlinear optical properties

ELECTROCHEMICAL STUDIES ON CONDUCTING COMPOSITE FILMS FROM POLYURETHANE AND POLYPYRROLE

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Chinese Journal of Polymer Science 1988年第4期6卷 377-385页

作者：毕先同裴啟兵李永舫 Institute of Chemistry academia sinica academia sinica Beijing

A study on the electrooxidative polymerization of pyrrole onto polyurethane-coated platinum electrodes and the electrochemical properties of the composite polyurethane/polypyrrole films （PU/PPy） as-prepared is presented. It is found that polypyrrole grows layer by layer from the polyurethane/platinum interface through the polyurethane matrix, and ca. 20 wt.% of polypyrrole will fill up the matrix. Cyclic voltemmograms show that the composite films are porous, and the reduction-reoxidation （redox） rate of the composite films is limited by the diffusion of counteranions through the films. Larger anion size leads to slower diffusion process. The composite films can also act as modified electrodes.

关键词： Polypyrrole, Conducting composite Electrochemistry

Instantaneous Temperature-rise History and Nonequilibrium Thermophysical Properties of Thin Films Irradiated by Transient Laser Pulse

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Science China Mathematics 1993年第1期36卷 109-116页

作者：唐大伟曹卉周本濂何冠虎张才根 Institute of Metal Research academia sinica International Center for Materials Physics Academia Sinica Shanghai Institute of Technical Physics Academia Sinica

Recent development in the study of nonequilibrium thermophysical properties of thin films in our lab is reported. A high-speed indirect heating system by using 0.1 μs CO_2 laser pulse was established. A photoelectric installation for micrometric length-change measurement, an infrared radiation pyrometer for transient temperature measurement, a high-speed acquisition system as recording device and microcomputer system for data treatmeat were developed. Using the systems, the traditional flash method is extended to the measurement of thermal diffusivity of the thin films of around 50 μm in thickness, and deviations of this method is analyzed for the case of thin film specimens. Nonsynchronous change of temperature rise and thermal expansion under transient heating was observed.

关键词： instantaneous temperature-rise history thin films nonequilibrium thermophysical properties transient laser pulse.

EXPRESSION OF SURFACE ANTIGEN GENE OF HUMAN HEPATITIS B VIRUS SEROTYPE adr IN Escherichia coli

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中国科学B辑(英文版) 1985年第6期28卷 618-625页

作者：敖世洲周翊钟潘铁城李载平 Shanghai Institute of Biochemistry academia sinica academia sinica

The construction of an expression plasmid of hepatitis B virus surface antigen (HBsAg) gone from the cloned hepatitis B virus (HBV) genome subtype adr is reported. The expression products of this plasmid in E. coli were detected by means of radioimmunoassay in competitive suppression and polyacrylamide-SDS gel electrophoresis. The presence of a fusion protein containing HBsAg was confirmed.

关键词： plasmid cloned SURFACE suppression competitive Agarose linker polyacrylamide agarose HBsAb

THE RHEO-OPTICAL FTIR STUDY OF POLYESTERPOLYETHER SEGMENTED COPOLYMER

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Chinese Journal of Polymer Science 1988年第4期6卷 325-331页

作者：闻再庆沈德言赵恒奇 Institute of chemistry academia sinica academia sinica Beijing

The polyester-polyetber segmented copolymer has been investigated by rheo-optical FTIR during stretehing for the informastion on strain induced crystallizatinn of soft segment chains, hard and soft chain *** room temperature 15℃, the soft segment chains of polyester-polyether being to crystallize at 220% strain and the degree of crystallixation increa(?)e with draw ratio, but there will not be any soft segment chains crystallization above 21℃even at bigber strain. The average orientation of hard segment chains are higher than that of the soft chain at high strain level, both are positive oriented into the stretching direction at allover strain level. This indicates that the b(?)d (?)ent ch(?)ins are dispersed into the elastomeric phase and without forming spherulite.

关键词： Rheo-optical FTIR Segmented copolymer Polyester-Polyether

MECHANISM OF INTERFERON ACTION Ⅹ——ANTAGONISTIC EFFECT OF ATP ON pppA2’p5’A2’p5’A RECEPTOR

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中国科学B辑(英文版) 1988年第3期31卷 304-312页

作者：李世武刘新垣 Shanghai Institute of Biochemistry academia sinica academia sinica

pppA2’p5’A2’p5’A （2’-5’P3A3） receptor may be the first one in the oligonucleotide *** ATP can compete with 2’-5’P3A3 for the receptor. This raises a question whether this is anATP receptor. If not, what is the role of ATP for this receptor? Data available in this arti-cle show that ATP can bind to macrophages with saturability and reversibility. So ATPappears to be also a ligand of the receptor for 2’-5’P2A3. But the binding of ATP did notdevelop phagocytic effect as mentioned before[11]. Moreover, ATP inhibited the enhancementof phagocytosis of macrophages by 2’-5’P3A3 when it acted together with 2’-5’P3A3 on mac-rophages at the same time. It is concluded that ATP is an antagonist of 2’-5’P3A3 *** macrophages were treated with ATP prior to 2’-5’P3A3 and the binding sites for 2’-5’P3A3P were first occupied by ATP, both the binding ability and the biological effect of2’-5’P3A3 were all markedly blocked. The above data convincingly show that the action of2’-5’P3A3 is

关键词： macrophages ACTION markedly phagocytic inhibited blocked prior compete mentioned antagonist