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Chinese Physics B 2018年第12期27卷 64-70页

作者： guo-yang ca Cheng Zhang Shao-Long Wu Dong Ma Xiao-Feng Li School of Optoelectronic Science and Engineering &Collaborative Innovation Center ofSuzhou Nano Science and Technology Soochow University Suzhou 215006China Key Laboratory of Advanced Optical Manufacturing Technologies of Jiangsu Province Key Laboratory of Modern Optical Technologies of the Education Ministry of ChinaSoochow UniversitySuzhou 215006China School of Rail Transportation Soochow UniversitySuzhou 215131China

Ultrathin optical interference in a system composed of absorbing material and metal reflector has attracted extensive attention due to its potential application in realizing highly efficient optical absorption by using extremely thin semiconductor material. In this paper, we study the physics behind the high absorption of ultrathin film from the viewpoint of destructive interference and admittance matching, particularly addressing the phase evolution by light propagation and interface reflection. The physical manipulations of the ultrathin interference effect by controlling the substrate material and semiconductor material/thickness are examined. We introduce typical two-dimensional materials — i.e., MoS2and WSe2— as the absorbing layer with thickness below 10 nm, which exhibits ～ 90% absorption in a large range of incident angle(0°～70°). According to the ultrathin interference mechanism, we propose the ultrathin(cation and carefully examine the detailed optoelectronic responses by coupled multiphysics simulation. By comparing the same cells on SiO2substrate, both the short-circuit current density(up to 20 mA/cm~2) and the photoelectric conversion efficiency(up to 9.5%) are found to be increased by ～200%.

关键词： photovoltaic subwavelength structures interference coating

The centrosymmetric to non-centrosymmetric transformation induced by alkaline-earth cations producing infrared nonlinear optical AeMn_(6)Ga_(6)S_(16)(Ae=ca,Sr)

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Science China Chemistry 2024年第9期67卷 2941-2948页

作者： yang-Ping Zhang Shao-Min Pei Wen-Fa Chen Bin-Wen Liu Xiao-Ming Jiang guo-Cong guo State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China School of Physical Science and Technology Shanghai Tech UniversityShanghai 201210China

Non-centrosymmetric(NCS)structure is an indispensable prerequisite for second-order nonlinear optical(NLO)***,the mainstream approach for designing new NCS structures still relies on chemical substitution,necessitating an urgent infusion of fresh *** this work,two isomorphic sulfides AeMn_(6)Ga_(6)S_(16)(Ae=ca,1;Sr,2)are afforded by modifying the skeleton of centrosymmetric(CS)Mn_(2)Ga_(2)S_(5) via introducing strong electropositive alkaline-earth ***,the incorporation of ca^(2+)/Sr^(2+)cations allows the elementary[MnGaS_(9)]_(∞)chains to reconfigure into bumpy[MnS_(6)]-[GaS_(4)]layers in a new engagement manner,thus enabling the conversion from CS to NCS *** modifications cause not only strong second-harmonic generation(SHG)responses(~1.5×benchmark AgGaS_(2)@1,700 nm),but also significantly feasible bandgaps(2.60-2.64 e V)compared to the sulfide Mn_(2)Ga_(2)S_(5)(1.36 e V),which ultimately facilitate ultrahigh laser-induced damage thresholds(4.4-6.6×AgGaS_(2)@1,064 nm for compounds 1 and 2).The present study offers an ingenious approach for the transformation of CS to NCS structure.

关键词： second-harmonic generation non-centrosymmetrical structure NLO functional motif solid-state method

Destruction of charge ordering phase in La_(0.4)ca_(0.6)MnO_3 induced by low Cr doping

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Rare Metals 2011年第3期30卷 241-246页

作者： PENG Zhensheng yang Gang WANG Guiying TANG Yonggang guo Huanyin MAO Qiang Anhui Key Laboratory of Spintronic and Nanometric Materials Cultivating Base Suzhou College Suzhou 234000 China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of China Hefei 230026 China Department of Electronics and Electric Engineering Suzhou College Suzhou 234000 China

Polycrystalline samples of La0.4cao.6Mn1-xCrxO3 （x = 0.00, 0.02, 0.04, 0.06） were prepared by the solid state reaction method. The influence of Cr3＋ substitution for Mn3＋ on the magnetic property and charge ordering phase of La0.4ca0.6MnO3 was studied through the measurements of X-ray diffraction （XRD）, magnetization-temperature （M-T） curves and electron spin resonance （ESR） spectra. The experimental results indicate that the mother＇s body of La0.4ca0.6MnO3 has very complicated magnetic structure, exhibits charge ordering phase at 258 K, and shows long-range strongly correlated charge ordering-antiferromagnetism （CO-AFM） phase from 175 to 50 K. Spin glass state appears when the temperature decreases to about 41 K. When the Cr substitution amount is x = 0.06, the charge ordering phase of the mother＇s body is de-stroyed, because the Cr3＋ substitution for Mn3＋ destroys the spin order of CE-type antiferromagnetism, and thus leads to the melting of charge ordering. It is verified experimentally that the strong coupling between charge order and spin order exists in the charge order system of CE-type antiferromagnetism.

关键词： perovskite manganite chromium doping charge ordering spin-glass state

Effect of rolling technologies on the properties of Pb?0.06wt%ca?1.2wt%Sn alloy anodes during copper electrowinning

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International Journal of Minerals,Metallurgy and Materials 2015年第11期22卷 1205-1211页

作者： Jian yang Bu-ming Chen Hui Hang Zhong-cheng guo Shuai Wang Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology Kunming Hendera Science and Technology Co. Ltd.

The objective of this work was to study the effect of different rolling technologies on the properties of Pb-0.06wt%ca-1.2wt%Sn anodes during copper electrowinning and to determine the relationship between the properties of the anodes and rolling techniques during copper electrowinning. The anode process was investigated via anodic polarization curves, cyclic voltammetry curves, electrochemical impedance spectra, and corrosion tests. The microscopic morphology and phase composition of the anodic oxide layers were observed by scanning electron microscopy and X-ray diffraction, respectively. Observable variations in the electrocatalytic activity and reaction kinetics of anodes during electrowinning indicated that the electrochemical behavior of the anodes was strongly affected by the rolling technology. An increase in the rolling number tended to decrease the oxygen evolution overpotential and the corrosion rate of the anodes. These trends are contrary to that of the apparent exchange current density. Furthermore, the intensities of diffraction peaks associated with PbO, PbOx, and α-PbO2 tended to increase with increasing rolling number. In addition, the rolled anodes exhibited a more uniform microstructure. Compared with one-way rolled anodes, the eight-time cross rolled anodes exhibited better electrocatalytic activity and improved corrosion resistance.

关键词： anode materials lead calcium tin alloys rolling electrocatalysis corrosion rate electrowinning

Targeting TrkB–PSD-95 coupling to mitigate neurological disorders

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Neural Regeneration Research 2025年第3期20卷 715-724页

作者： Xin yang Yu-Wen Alvin Huang John Marshall Department of Molecular Biology Cell Biology and BiochemistryBrown UniversityProvidenceRIUSA Department of Neurology Warren Alpert Medical School of Brown UniversityProvidenceRIUSA Center for Translational Neuroscience Robert J.and Nancy D.Carney Institute for Brain Science and Brown Institute for Translational ScienceBrown UniversityProvidenceRIUSA

Tropomyosin receptor kinase B(TrkB)signaling plays a pivotal role in dendritic growth and dendritic spine formation to promote learning and *** activity-dependent release of brain-derived neurotrophic factor at synapses binds to pre-or postsynaptic TrkB resulting in the strengthening of synapses,reflected by long-term ***,the association of postsynaptic density protein-95 with TrkB enhances phospholipase Cγ-ca^(2+)/calmodulin-dependent protein kinaseⅡand phosphatidylinositol 3-kinase-mechanistic target of rapamycin signaling required for long-term *** this review,we discuss TrkB-postsynaptic density protein-95 coupling as a promising strategy to magnify brain-derived neurotrophic factor signaling towards the development of novel therapeutics for specific neurological disorders.A reduction of TrkB signaling has been observed in neurodegenerative disorders,such as Alzheimer's disease and Huntington's disease,and enhancement of postsynaptic density protein-95 association with TrkB signaling could mitigate the observed deficiency of neuronal connectivity in schizophrenia and *** with brain-derived neurotrophic factor is problematic,due to poor pharmacokinetics,low brain penetration,and side effects resulting from activation of the p75 neurotrophin receptor or the truncated TrkB.T1 *** TrkB agonists and antibodies that activate TrkB are being intensively investigated,they cannot distinguish the multiple human TrkB splicing isoforms or cell type-specific *** TrkB–postsynaptic density protein-95 coupling provides an alternative approach to specifically boost TrkB signaling at localized synaptic sites versus global stimulation that risks many adverse side effects.

关键词： Angelman syndrome autism brain-derived neurotrophic factor depression neurodegenerative disorder neurodevelopmental disorder postsynaptic density protein-95 synaptic plasticity TrkB

Longitudinal vibrations of arbitrary non-uniform rods

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Acta Mechanica Solida Sinica 2015年第2期28卷 187-199页

作者： Shuqi guo Shaopu yang Department of Engineering Mechanics Shijiazhuang Tiedao University School of Mechanical Engineering Shijiazhuang Tiedao University

Free and steady-state forced longitudinal vibrations of non-uniform rods are investi- gated by an iteration method, which results in a series solution. The series obtained are convergent and linearly independent. Its convergence is verified by convergence tests, its linear independence confirmed by the nonzero value of the corresponding Wronski determinant. Then, the solution obtained is an exact one reducible to a classical solution for the case of uniform rods. In order to verify the method, two examples are presented as an application of the proposed method. The results obtained are equivalent to the method in literature. In contrast to the proposed method ca- pable of dealing with arbitrary non-uniform rods in principle, the method in literature is confined to work on special cases.

关键词： longitudinal vibration arbitrary non-uniform rod series solution convergence

Structural phase transition, precursory electronic anomaly, and strong-coupling superconductivity in quasi-skutterudite (Sr1-xcax)3Ir4Sn13 and ca3Rh4Sn13

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Chinese Physics B 2018年第7期27卷 163-170页

作者： Jun Luo Jie yang S Maeda Zheng Li guo-Qing Zheng Institute of Physics Chinese Academy of Sciences and Beijing National Laboratory for Condensed Matter Physics Beijing 100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing 100049 China Department of Physics Okayama University Okayama 700-8530 Japan

The interplay between superconductivity and structural phase transition has attracted enormous interest in recent years. For example, in Fe-pnictide high temperature superconductors, quantum fluctuations in association with structural phase transition have been proposed to lead to many novel physical properties and even the superconductivity itself. Here we report a finding that the quasi-skutterudite superconductors （Sr1-xcax）3Ir4Sn13 （x = 0, 0.5, 1） and ca3Rh4Snl3 show some unusual properties similar to the Fe-pnictides, through 119Sn nuclear magnetic resonance （NMR） measurements. In （Sr1-xcax）3Ir4Sn13, the NMR linewidth increases below a temperature T＊ that is higher than the structural phase transition temperature Ts. The spin-lattice relaxation rate （1/T1 ） divided by temperature （T）, 1/TI T and the Knight shift K increase with decreasing T down to T＊, but start to decrease below T＊, and followed by more distinct changes at Ts. In contrast, none of the anomalies is observed in ca3Rh4Sn13 that does not undergo a structural phase transition. The precursory phenomenon above the structural phase transition resembles that occurring in Fe-pnictides. In the superconducting state of ca3Ir4Sn13, 1/T1 decays as exp（-△/kBT） with a large gap △ = 2.21kBTc, yet without a Hebel-Slichter coherence peak, which indicates strong-coupling superconductivity. Our results provide new insight into the relationship between superconductivity and the electronic-structure change associated with structural phase transition.

关键词： nuclear magnetic resonance antiferromagnetic fluctuation structural phase transition phase diagram

Abnormal Twinning Behavior and Constitutive Modeling of a Fine-Grained Extruded Mg-8.0Al-0.1Mn-2.0ca Alloy under High-Speed Impact along Various Directions

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Acta Metallurgica Sinica(English Letters) 2023年第2期36卷 281-294页

作者： Fei-yang Chen Peng-Cheng guo Zi-Han Jiang Xiao Liu Tie-Jun Song Chao Xie College of Mechanical and Electrical Engineering Central South University of Forestry and TechnologyChangsha410004China College of Mechanical Engineering and Mechanics Ningbo UniversityNingbo315211China College of Mechanical Engineering Xiangtan UniversityXiangtan411105China College of Material Science and Engineering Hunan University of Science and TechnologyXiangtan411201China

To understand the mechanical and twinning behaviors of a fine-grained extruded Mg-8.0Al-0.1Mn-2.0ca alloy under high-speed impact,impact tests were carried out using a split Hopkinson pressure bar,and microstructures at strains of 0.05,0.10 and 0.20 were obtained using a series of stop rings manufactured by high-strength *** stress response and twinning behavior are closely related to loading direction and applied strain *** true stress-true strain curves are s-shaped in extrusion direction(ED)and c-shaped in transverse direction(TD),showing apparent anisotropy,while the yield strength is insensitive to loading *** identical strain-rate sensitivity is demonstrated by the stress in ED and ***,de-twinning is apparent as the applied strain increases to 0.20,and it is enhanced with increasing the applied strain *** contrast,the twin density in ED samples is clearly higher than that in TD *** modifying the terms of strain hardening and strain rate hardening in the classical JC model,an optimized model is built,which can accurately predict the stress response behavior of the studied alloy under high-speed impact along ED and *** correlation coefficient(R)and average absolute relative error(AARE)are 98.63%and 0.0199 for ED,and 96.88%and 0.0202 for TD,respectively.

关键词： High-speed impact Magnesium alloy Twinning behavior Constitutive model Anisotropy

Optical spectroscopy study of charge density wave orderOptical spectroscopy study of charge density wave order in Sr_3Rh_4Sn_(13) and (Sr_(0.5)ca_(0.5))3_Rh_4Sn_(13)

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Science China(Physics,Mechanics & Astronomy) 2017年第4期60卷 57-61页

作者： Qian Wan KuiJuan Jin JieSu Wang HongBao Yao JunXing Gu HaiZhong guo XiuLai Xu guoZhen yang Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences Collaborative Innovation Center of Quantum Matter

The ultrafast laser-excited magnetization dynamics of ferromagnetic （FM） La0.67Sr0.33MnO3 （LSMO） thin films with BiFeO3 （BFO） coating layers grown by laser molecular beam epitaxy are investigated using the optical pump-probe technique. Uniform magnetization precessions are observed in the films under an applied external magnetic field by measuring the time-resolved magneto-optical Kerr effect. The magnetization precession frequencies of the LSMO thin films with the BFO coating layers are lower than those of uncoated LSMO films, which is attributed to the suppression of the anisotropy field induced by the exchange interaction at the interface between the antiferromagnetic order of BFO and the FM order of LSMO.

关键词： magnetization precession ultrafast time-resolved magneto-optical Kerr effect perovskite oxide interface

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Hydrothermal synthesis,characterization and nonlinear optical effect of orthorhombic phase ca_(2)B_(6)O_(11)·H2O

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Chinese Science Bulletin 2000年第19期45卷 1756-1760页

作者： Fan guo Peizhen Fu Junxin Wang Feng Liu Zhiping yang Yicheng Wu Department of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Department of Chemistry University of Science and Technology of ChinaHefei 230026China

Hydrothermal treatment of calcium oxide and boric acid mixtures at temperaturesbetween 234 ℃ and 300 ℃ has produced a colorless, transparent, orthorhombic compound ca2B6O11 · H2O. Of the seven known members of the series of hydrated dicalcium hexaborate containing boron-oxygen six-membered ring anionic group (B3O8)7, only the title compound has been found to have the nonlinear optical effect. The second harmanic generation (SHG) effect of its crystal is larger than that of KH2PO4 (KDP). The reflection spectrum has shown that this compound has no absorption in the experimental wavelength range (800-240 nm). Its crystal structure is favorable for generating the nonlinear optical effect.

关键词： nonlinear optical crystal hydrothermal synthesis ca_(2)B_(6)O_(11)·H2O calcium borate (B_(3)O_(8))^(7)