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Higher-Order Lagrangian Equations of Higher-Order Motive Mechanical System

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Communications in Theoretical Physics 2008年第2期49卷 479-481页

作者： zhao hong-Xia MA Shan-Jun SHI Yong College of Physics and Communication Electronics Jiangxi Normal University Nanchang 330022 China

In this paper, if the condition of variation δt = 0 is satisfied, the higher-order Lagrangian equations and higher-order Hamilton＇s equations, which show the consistency with the results of traditional analytical mechanics, are obtained from the higher-order Lagrangian equations and higher-order Hamilton＇s equations. The results can enrich the theory of analytical mechanics.

关键词： higher-order Lagrange function Hamilton function higher-order Lagrangian equation

Perturbation to Symmetries and Adiabatic Invariants of Nonholonomic System in Terms of Quasi-coordinates

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Communications in Theoretical Physics 2005年第5X期44卷 773-778页

作者： CHEN Xiang-Wei zhao Yong-hong LI Yan-Min Department of Physics Shangqiu Teachers College Shangqiu 476000 China

Based on the theory of Lie symmetries and conserved quantities, the exact invariants and adiabatic invariants of nonholonomic system in terms of quasi-coordinates are studied. The perturbation to symmetries for the nonholonomic system in terms of quasi-coordinates under small excitation is discussed. The concept of high-order adiabatic invariant is presented, and the forms of exact invariants and adiabatic invariants as well as the conditions for their existence are given. Then the corresponding inverse problem is studied.

关键词： nonholonomic system in terms of quasi-coordinates perturbation exact invariant adiabatic invariant

A computational investigation of topological insulator Bi2Se3 film

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Frontiers of physics 2014年第6期9卷 760-767页

作者： Yi-Bin Hu Yong-hong zhao Xue-Feng Wang Department of Physics MeGill University 3600 rue University Montrdal Qudbec H3A 2T8 Canada College of Physics and Electronic Engineering Institute of Solid State Physics Sichuan Normal University Chengdu 610068 China Department of Physics Soochow University Suzhou 215006 China

Topological insulators have a bulk band gap like a.n ordinary insulator and conducting states on their edge or surface which are formed by spin orbit coupling and protected by time-reversal sylnmetry. W＇e report theoretical analyses of tile electronic properties of three-dimensional topological insulator Bi2Sea film on different energies. We choose five different energies （ 123, -75, 0, 180. 350 meV） around the Dirac cone （ 113 meV）. When energy is close to the Dirac cone. the properties of wave function Inatch the topological insulator＇s halhnark perfectly. When energy is far way from tile Dirac cone, the halhnark of topological insulator is broken and the helical states disappear. The electronic properties of helical states are dug out fi＇om the calculation results. The spin-inomentum locking of the helical StatES are confirmed. A 3-fold symmetry of the helical states in Brillouin zone is also revealed. The penetration depth of tile helical states is two quintuple layers which can be identified from layer projection. Tile charge contribution on each quintuple layer depends on the energy, and has completely different behavior along K and M direction in Brillouin zone. From orbital projection, we can find that the maximum charge contribution of the helical states is p： orbit and the charge contribution on py and Px orbits have 2-fold symmetry.

关键词： topological insulator spin-orbit coupling helical state

Progress in Modeling of Phase Transformation Kinetics

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Journal of Iron and Steel Research International 2006年第3期13卷 68-73页

作者： zhao hong-zhuang LIU Xiang-hua WANG Guo-dong State Key Lab of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

Several methods representing the evolution of microstructure were introduced, which include the Johnson-Mehl-Avrami-Kolmogorov （JMAK） equation, Internal State Variable （ISV） framework, Koistinen-Marburger （K-M） equation, modified Magee＇s rule and phase field model, etc. By combining calculation of martensite transformation kinetics, considering the selection of parameters with the effect of austenite grain size （AGS）, some suitable ways of obtaining better results have been proposed.

关键词： phase transformation kinetics modeling numerical simulation

Analgesic and anti-inflammatory activity of Cotinus coggygria *** in vivo

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Asian Pacific Journal of Tropical Biomedicine 2024年第6期14卷 225-235页

作者： Kai Lu Chong-Yu Yang zhao-hong Yan Department of Anesthesiology Qiantang Campus Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou310018China Department of Anesthesiology 3201 HospitalHanzhong723000China Department of Anesthesiology The Second Affiliated Hospital of the Chinese People’s Liberation Army Air Force Medical UniversityXi’an710038China

Objective:To assess the analgesic and anti-inflammatory effects of standardized extract of Cotinus coggygria(***)in different animal ***:*** extracts(25,50,and 100 mg/kg)were administered to rats and mice(n=6)during hot plate,tail-flick,acetic acid-induced writhing,and formalin tests to determine its analgesic *** anti-inflammatory activity of *** extracts was evaluated by histamine and carrageenan-induced paw edema,cotton pellet-induced granuloma,and acetic acid-induced peritoneal capillary dye leakage ***:*** extracts(50 and 100 mg/kg)significantly alleviated thermal and chemical-induced pain in rodents(P<0.05).It also demonstrated notable anti-inflammatory properties by mitigating histamine and carrageenan-induced paw edema,granuloma deposits,and vascular permeability(P<0.05).Moreover,*** extracts remarkably reduced TNF-α,IL-1β,IL-6,COX-2,and oxidative stress in rat paws(P<0.05).Carrageenan-induced histological aberrations in hind paw tissues were effectively(P<0.05)mitigated by treatment with *** ***:*** *** show analgesic and anti-inflammatory effects via inhibition of COX-2 and inflammatory and oxidative mediators.

关键词： Antioxidant Carrageenan Cotinus coggygria Scop. Anti-inflammatory Analgesic Pain TNF-α Fustin

Causes for the Unimodal Pattern of Leaf Carbon Isotope Composition in Abies faxoniana Trees Growing in a Natural Forest along an Altitudinal Gradient

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Journal of Mountain Science 2015年第1期12卷 39-48页

作者： zhao hong-xia DUAN Bao-li LEI Yan-bao Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences

Leaf morphological and physiological traits of Abies faxoniana growing in a natural forest along an altitudinal gradient were measured with the aim to identify the central mechanism for the marked variation in foliar δ13C determined by an isotope ratio mass spectrometer. There is a unimodal pattern of plant functional traits in these temperate and semi- humid areas. Stomatal parameters, specific leaf area, and C/N ratio increased, whereas C, N and δ13C values decreased with increasing altitude below 3000 m a.s.1. In contrast, they exhibited opposite trends above 3000 m a.s.l.. Our results demonstrated that high-altitude plants achieve higher water use efficiency （WUE） at the expense of decreasing nitrogen use efficiency （NUE）, whereas plants at 3000 m can maintain a relatively higher NUE but a lower WUE. Such intra-specific differences in the trade-off between NUE and WUE may partially explain the altitudinal distribution of the plants in relation to moisture and nutrient availability. Our results clearly indicate that the functional relations between nutritional status and the structure of leaves are responsible for the altitudinal variations associated with δ13C. The pivotal role of specific leaf area in regulating plant adaptive responses provides a potential physiological mechanism for the observed growth advantage of populations occupying the medium altitude. These adaptive responses altitudinal gradients showed that an altitude to of approximately 3000 m a.s.1, is the optimum distribution zone for A. faxoniana, allowing the most vigorous growth and metabolism. These results improve our understanding of the various roles of environmental and biotic variables upon δ13C dynamics and provide useful information for subalpine coniferous forest management.

关键词： Abiesfaxoniana Age Altitude Carbonisotope ratio Nitrogen content

Tunable band structure and effective mass of disordered chalcopyrite

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Frontiers of physics 2017年第1期12卷 51-56页

作者： Ze-Lian Wang Wen-Hui Xie Yong-hong zhao College of Physics and Electronic Engineering Institute of Solid State Physics Sichuan Normal University Chengdu 610068 China Department of Physics East China Normal University Shanghai 200062 China

The band structure and effective mass of disordered chalcopyrite photovoltaic materials Cul-xAgxGaX2 （X = S, Se） are investigated by density functional theory. Special quasirandom structures are used to mimic local atomic disorders at Cu/Ag sites. A local density plus correction method is adopted to obtain correct semiconductor band gaps for all compounds. The bandgap anomaly can be seen for both sulfides and selenides, where the gap values of Ag compounds are larger than those of Cu compounds. Band gaps can be modulated from 1.63 to 1.78 eV for CU1-xAgxGaSe2, and from 2.33 to 2.64 eV for Cu1-xAgxGaS2. The band gap minima and maxima occur at around x = 0.5 and x = 1, respectively, for both sulfides and selenides. In order to show the transport properties of Cu1-xAgxGaX2, the effective mass is shown as a function of disordered Ag concentration. Finally, detailed band structures are shown to clarify the phonon momentum needed by the fundamental indirect-gap transitions. These results should be helpful in designing high-efficiency photovoltaic devices, with both better absorption and high mobility, by Ag-doping in CuGaX2.

关键词： disorder electronic structure effective mass

Effect of the synthesis method of SnSb anode materials on their electrochemical properties

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Journal of University of Science and Technology Beijing 2007年第4期14卷 345-349页

作者： Chaoli Yin Hailei zhao hong Guo Xianliang Huang Weihua Qiu Department of Inorganic Nonmetallic Materials University of Science and Technology Beijing Beijing 100083 China

SnSb alloy powders for the anode of Li-ion batteries were synthesized by two kinds of reduction precipitation methods： solution titration and rapid mixing. Two kinds of SnSb alloy powders showed different phase compositions and particle morphologies although the same starting materials were used. The SnSb alloy electrode synthesized by titration exhibits high reversible specific capacity and good cycling stability, whereas the rapid-mixing sample shows high irreversible capacity and fast capacity fade. The broad particle size distribution of SnSb powders synthesized by titration is considered to be responsible for the improvement of cycling stability. The initial charge-discharge efficiency exceeding 80% has been obtained for the titration sample. The electrochemical reaction process of two kinds of synthesized SnSb composite electrodes was characterized by cyclic voltammetry and AC impedance techniques.

关键词： SnSb alloys lithium-ion batteries anode electrochemical properties

Different Features of Jets and Isotropic Fireballs in Gamma-ray Burst Phase

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Chinese Journal of Astronomy and Astrophysics 2006年第1期6卷 69-76页

作者： Yun-Ming Dong Lan-Wei Jia Xiao-hong zhao Yunnan Astronomical Observatory/National Astronomical Observatories Chinese Academy ofSciences Kunming 650011 Graduate University of Chinese Academy of Sciences Beijing 100049

We investigated physical quantities including the spectrum, emission lines and pulse profiles expected from a uniform jet, a spherical fireball and the 1/Г region （the portion of the spherical fireball with opening angle 1/Г） in the prompt emission phase, after taking into consideration of the Doppler effect under the fireball framework. Our study shows that： a） for these physical quantities the spherical fireball and the uniform jets do not present obvious differences, so we cannot use these to distinguish a spherical fireball from a uniform jet; b） for the spherical fireball and a uniform jet, the observed quantities mainly come from the 1/Г region, so we can simply use the 1/Г region in approximate calculations; c） broadening of emission lines is a general phenomena, which mainly comes from the curvature effect; d） the 1/Г region plays different roles in different frequency ranges, and the radiation from the 1/Г region is greater in the higher than in the lower frequencies.

关键词： gamma-rays: bursts--gamma-rays: theory--radiation mechanisms: non-thermal --relativity