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New topological semimetai Candidate of nonsymmorphic PdSb2 with unique six-fold degenerate point

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Frontiers of physics 2019年第4期14卷 1-3页

作者： Guangcun Shan hai-Bin gao School of Instrument Science and Opto-electronic Engineering & Institute of Quantum Sensing Beihang University Beijing 100083 China Max Planck Institute for Chemical Physics of Solids Nothnitzer Str. 40 D-01187 Dresden Germany Institute of Experimental Physics Saarland University 66123 Saarbriicken Germany

Since the discovery of Majorana fermions in condensed matter systems, new quasiparticle predictions of novel fermions have been predicted in solid state systems which exhibit three, six or eight fold degenerate band crossings protected by crystal symmetty in presence of spin orbit coupling and time reversal symmetry [1]. The nontrivial topology in condensed matter systems results from the crossings of conduction and valence bands. And the cases of g = 3, 6, and 8 are of particularly interesting as they can only be found in condensed matter systems, having no high energy analogues as constrained by Poincare symmetry [2].

关键词： discovery fermions time

CROSSLINKED ORGANOSILOXANE HYBRID MATERIALS PREPARED BY CONDENSATION OF SILANOL AND MODIFIED SILICA: SYNTHESIS AND CHARACTERIZATION

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Chinese Journal of Polymer Science 2013年第7期31卷 974-983页

作者： Da-hai gao 贾梦秋 Ying Luo College of Materials Science and Engineering Beijing University of Chemical Technology Nuclear Power Institute of China

Hybrid materials based on polymethylphenylsiloxane （PMPS） and organic functionalized silica were synthesized via condensation reaction between silanol and alkoxysilyl groups in the presence of quaternary ammonium hydroxide. The structure of prepared materials was investigated by FTIR and NMR, which indicate that the products have incorporated modified silica into the polymer matrix. The prepared hybrid materials show a satisfactory thermal resistance because the initial decomposition of typical product occurred at nearly 100 K higher than that of the pure polymer according to the thermogravimetric analysis （TGA） results. Differential thermogravimetric analysis （DTGA） data confirm that the thermal degradation of prepared hybrid materials comprises of two steps, of which the first one could be controlled by adjusting the content of silica particles and the ratio of surface groups on the particles. The coating films obtained from hybrid products exhibit good thermal mechanical properties. Therefore, the materials are hoped to be used for the application in thermal resistant coating.

关键词： Hybrid material Crosslinked polysiloxane Condensation polymerization Thermal stability.

Manufacture and characteristics of Al2O3 composite coating on steel substrate by SHS process

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Rare Metals 2019年第7期38卷 704-712页

作者： hai-Dong gao Ze-Hua Wang Jia Shao College of Mechanics and Materials Hohai University

Many steel components are needed to be reinforced on their surface to have a high abrasive resistance and corrosion resistance. Based on self-propagating hightemperature synthesis, a process to making Al2O3 composite coatings on mild steel substrate in atmospheric environment with the help of simple auxiliary facilities was developed successfully. A pre-coated bilayer coating was employed. The effects of Fe content in pre-coated transition layer on phase composition, porosity and interfacial bon ding were studied using scanning electron microscopy (SEM), energy-dispersive spectrum (EDS) and X-ray diffraction (XRD). The thermal shock resistance and abrasive resistance were investigated. When Fe content changes from 0 wt% to 50 wt%, the bond quality at first becomes better and then worse gradually. When Fe content is less 20 wt%, there is a small gap between the transition layer and the substrate;when Fe contents are 30 wt% and 40 wt%, working layer, the transition layer and the substrate bond together well. The working layer is mainly composed of Al2O3, Fe-Cr and Al(Cr)2O3 phases and has a dense structure with porosity of less than 1 %. The coating has a good thermal shock resistance and abrasive resistance. The abrasive resistance of the working layer is about ten times that of the substrate.

关键词： Al2O3 composite coating Self-propagating high-temperature synthesis Interfacial bonding Thermal shock resistance Abrasive resistance

Synthesis, Characterization, and Catalytic Ethylene Oligomerization of Pyridine-imine Palladium Complexes

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Chinese Journal of Polymer Science 2018年第2期36卷 176-184页

作者： Xiao-Lin Chen Jie gao Heng Liao hai-Yang gao Qing Wu School of Materials Science and Engineering Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education Guangdong Laboratory of High-performance Polymer Composites Sun Yat-sen University

Two neutral five-membered pyridine-imine palladium complexes with the bulky dibenzhydryl（CH（Ph）2） substituted aniline were synthesized and fully characterized by nuclear magnetic resonance（NMR） and X-ray crystal diffraction. Well-defined cationic palladium complexes were further obtained by treatment of chloromethylpalladium complexes with sodium tetrakis（3,5-bis（trifluoromethyl）phenyl）borate（NaBArF） in CH3CN. Cationic palladium complexes were capable of catalyzing ethylene oligomerization without any cocatalysts. The influences of catalyst structure, reaction temperature, and ethylene pressure on ethylene oligomerization were studied in detail. The introduction of bulky benzhydryl（CH（Ph）2） on the ortho position of the aniline moiety enhanced catalytic activity, thermal stability of the catalyst, and molecular weight of the obtained products. Highly branched oligomers with molecular weights of 600-800 g/mol and narrow polydispersities（1.03-1.12） were produced.

关键词： Palladium Ethylene Oligomerization Branching

Raman and UV-Vis Spectroscopy Applied to the Analysis of Liver Tissues from Rats with Myocardial Ischemia Induced by Isoproterenol

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Chemical Research in Chinese Universities 2011年第4期27卷 570-573页

作者： gao hai-cheng ZOU Ying-gang HUANG Yu-xin gao hai-mei CHEN Lei PEI Jin School of Pharmaceutical Sciences Jilin University Changchun 130012 P. R. China Department of Obstetrics ＆ Gynecology the Second Hospital of Jilin University Changchun 130041 P. R. China Basic Science College Changchun University of Technology Changchun 130012 P. R. China Key Laboratory for Molecular Enzymology and Engineering Ministry of Education Jilin University Changchun 130012 P. R. China

The application of the laser Raman spectroscopic（LRS） technique for the analysis of liver tissues from rats with myocardial ischemia induced by isoproterenol（ISO） was *** model of myocardial ischemia was established for rats induced by *** were randomly divided into four groups as normal group and myocardial ischemia *** observed the successful myocardial ischemia model via serum enzymes levels and hematoxylin-eosin（HE） staining,and detected the liver tissue of the rats from normal group and liver tissue of the rats from myocardial ischemia groups via UV-Vis spectroscopy（UV-Vis） and LRS,and the changes of the absorbance spectra were compared in the above four different *** results show that ISO can induce rat myocardial ischemia *** spectrum of normal liver tissue supernatant exhibits a strong absorption band at 968 nm,but no absorption band appears in the spectra of liver tissue supernatant solutions from the rats with myocardial ischemia induction after 2,12 and 72 h presented at 968 *** results show that Raman intensities of the precipitates suffered from ISO-treatment after 2,12 and 72 h were obviously increased compared with that of the precipitate of the liver tissue of the normal rats suffered from 0.9 g/L normal saline（NS） *** results indicate that LRS and UV-Vis can be harmless,nondestructive,rapid and effective methods for analyzing different pathological specimens of liver tissue from myocardial ischemia rats.

关键词： Laser Raman spectroscopy UV-Vis spectroscopy Isoproterenol Myocardial ischemia Rat Liver tissue

SYNTHESIS OF BIMODAL POLYETHYLENE WITH UNSYMMETRICAL α-DIIMINE NICKEL COMPLEXES: INFLUENCE OF LIGAND BACKBONE AND UNSYM-SUBSTITUTED ANILINE MOIETY

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Chinese Journal of Polymer Science 2013年第4期31卷 563-573页

作者： hai-yang gao Feng-shou Liu hai-bin Hu Fang-ming Zhu 伍青 DSAPM Lab PCFM LabInstitute of Polymer ScienceSchool of Chemistry and Chemical EngineeringSun Yat-Sen University

A series of unsymmetrical a-diimine nickel complexes with various backbones and substituted aniline moieties were synthesized and characterized. The crystallographic analysis of the nickel complexes confirmed the existence of meso-and rac-configuration in solid structure. Nickel complexes after activation by MAO were screened for ethylene polymerization to evaluate backbone substituent effect on synthesis of bimodal PE. Acenaphthyl nickel complex with planar backbone afforded a bimodal PE with a broad polydispersity, whereas camphyl nickel complex with rigid and bulky backbone afforded a monomodal PE with a narrow polydispersity. Steric effect of aniline moiety for acenaphthyl nickel complex was also examined, and bimodal PE with dominant high-molecular-weight fraction was obtained by modifying substituents on aniline moiety.

关键词： a-Diimine nickel Stereo-isomer Polyethylene Bimodal molecular weight distribution.

A linear complementarity model for multibody systems with frictional unilateral and bilateral constraints

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Acta Mechanica Sinica 2011年第4期27卷 587-592页

作者： hai-Ping gao Qi Wang Shi-Min Wang Li Fu Department of dynamics and control Beihang University 100191 Beijing China

The Lagrange-I equations and measure differential equations for multibody systems with unilateral and bilateral constraints are constructed. For bilateral constraints, frictional forces and their impulses contain the products of the filled-in relay function induced by Coulomb friction and the absolute values of normal constraint reactions. With the time-stepping impulse-velocity scheme, the measure differential equations are discretized. The equations of horizontal linear complementarity problems （HLCPs）, which are used to compute the impulses, are constructed by decomposing the absolute function and the filled-in relay function. These HLCP equations degenerate into equations of LCPs for frictional unilateral constraints, or HLCPs for frictional bilateral constraints. Finally, a numerical simulation for multibody systems with both unilateral and bilateral constraints is presented.

关键词： Coulomb friction Bilateral constraint Unilat-eral constraint - Horizontal linear complementarity problem(HLCP) Time-stepping impulse-velocity algorithm

Risk analysis of gastrointestinal bleeding in hospital patients with acute myocardial infarction undergoing primary PCI

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Journal of Geriatric Cardiology 2023年第5期20卷 386-390页

作者： Yan-Yan JIN Ming YE hai gao Center for Coronary Artery Disease Division of CardiologyBeijing Anzhen HospitalCapital Medical UniversityBeijingChina

Dual antiplatelet therapy with aspirin and a P2Y12 inhibitor is the cornerstone of acute myocardial infarction(AMI)management,both invasive and conservative.[1,2]This dual strategy improved ischemic outcomes but was offset by an increased bleeding *** prognostic importance of bleeding events has been well established over the past decades,as several studies have shown a strong association between bleeding and mortality.[3]The CRUSADE score is superior to other scores in predicting in-hospital major bleeding *** this regard,in its non-ST elevation acute coronary syndromes(NSTE-ACS)guidelines,the European Society of Cardiology(ESC)stated that the CRUSADE score could be considered for bleeding risk quantification of coronary angiography in NSTE-ACS patients(class IIb,level B evidence).[4]However,the most common site of spontaneous.

关键词： bleeding acute patients

Multiple Nonnegative Solutions for Singular Positone Boundary Value Problems to the Delay One-dimension p-Laplacian

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Acta Mathematicae Applicatae Sinica 2005年第3期21卷 405-414页

作者： Xiao-ning Lin hai-yin gao Business School of Northeast Normal University Department of Mathematics Northeast Normal UniversityChangchun 130024 China Applied Science College Changchun University Changchun 130022 China

The existence of multiple nonnegative solutions for singular positone boundary value problems to the delay one-dimension p-Laplacian is discussed in this paper.

关键词： Existcnce multiple nonnegative solutions singular boundary value problem delay differential cquation