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Atomic Structure of Cu49Hf42Al9 Metallic Glass with High Glass-Forming Ability and Plasticity

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Acta Metallurgica Sinica(English Letters) 2019年第7期32卷 803-807页

作者： Kai li Yu-Jen Chou Fang-liang Gao guo-qiang li State Key Laboratory of Luminescent Materials and Devices South China University of Technology Guangzhou 510640 China Engineering Research Center on Solid-State lighting and Its Informationisation of Guangdong Province South China University of Technology Guangzhou 510640 China Department of Electronic Materials School of Materials Science and Engineering South China University of Technology Guangzhou 510640 China Department of Materials University of Oxford Parks Road Oxford OXI 3PH UK

Electron diffraction was used to study the local atomic structure of Cu49Hf42Al9 metallic glasses (MGs). The amorphous nature of the MG was fully retained after the compression test. The partial radial distribution functions (PRDFs) of the MG structure obtained from the atomic model using reverse Monte Carlo and density functional theory optimization display that the peaks of the first nearest-neighbour distances for Cu-Cu, Hf-Cu and Hf-Hf atomic pairs were located at 2.56 A, 2.78 A and 3.23 A, respectively. The wide distribution of PRDF for Hf-Hf atomic pair explained the high plasticity of the material.

关键词： Metallic glass Radial distribution function Electron diffraction Density functional theory Atomic structure

Effect of bainite microstructure during two-step quenching and partitioning process on strength and toughness properties of a 0.3%C bainitic steel

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Journal of Iron and Steel Research International 2018年第2期25卷 235-242页

作者： Cheng-hui Su qiang-guo li Xue-fei Huang Wei-gang Huang College of Materials Science and Engineering SichuanUniversity Chengdu 610065 Sichuan China

The effect of bainite transformation and microstructure on the mechanical properties in 0.3%C bainitic steel was investigated via the heat treatment process of quenching at higher initial temperature and partitioning below martensite-start temperature. The results show that bainite transformation takes place with the partitioning time increasing during partitioning below martensite-start temperature. The microstructure of samples treated by this two-step quenching and partitioning process consists of lath bainite, lath martensite and retained austenite. This kind of multiphase microstructure exhibits better strength of 1420 MPa, ductility of 21.8 % and the product of strength and elongation of 30.8 GPa%. Furthermore, the excellent impact toughness of 103 J is exhibited by partitioning at 280 ℃ for 3 h. In addition, the coalescence of bainite platelets was found in the sample treated by partitioning for 8 h, leading to the deterioration of toughness.

关键词： Quenching and partitioning Bainitic steel Impact toughness Coalesced bainite

Two new olean-type triterpene fatty esters from Scorzonera mongolica

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Chinese Chemical Letters 2007年第6期18卷 708-710页

作者： Bin Wang guo qiang li Pei Ju Qiu Hua Shi Guan Institute of Marine Drugs and Food of Ocean University of China Qingdao 266003 China

Two new triterpene fatty esters, 3β-tetradecanoyl moradiol 1 and 3β-dodecanoyl moradiol 2, were isolated from Scorzonera mongolica. Their structures were elucidated as 3β-tetradecanoyloxy-28-hydroxylolean-18-ene and 3β-dodecanoyl-28-hydroxyl-olean-18-ene on the basis of IR, MS, 1D NMR and extensive 2D NMR spectroscopic analyses.

关键词： Scorzonera mongolica Moradiol Triterpene fatty esters

Three new non-brominated pyrrole alkaloids from the South China Sea sponge Agelas nakamurai

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Chinese Chemical Letters 2017年第6期28卷 1210-1213页

作者： Mei-Jun Chu Xu-li Tang guo-Fei Qin Nicole J.de Voogd Ping-lin li guo-qiang li Key Laboratory of Marine Drugs Chinese Ministry of Education School of Medicine and Pharmacy Ocean University of China Qingdao 266003 China Laboratory of Marine Drugs and Biological Products National Laboratory for Marine Science and Technology Qingdao 266235 China College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China National Museum of Natural History 2300 RA Leiden The Netherlands

Three new non-brominated pyrrole alkaloids,nakamurines A-C（1-3） were isolated from the South China Sea sponge Agelas *** structures were elucidated on the basis of spectroscopic *** 2 showed weak antimicrobial activ... 详细信息

关键词： Marine sponge The South China Sea Agelas nakamurai Pyrrole alkaloids Antimicrobial

Synthesis,Characterization and Standard Molar Formation Enthalpy of [Sm(C_7H_5O_3)_2(C_4H_6NO_2S)]·2H_2O

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Chemical Research in Chinese Universities 2009年第4期25卷 564-568页

作者： li Xu YANG De-jun li qiang-guo li Ai-tao YE li-juan JIANG Jian-hong Department of Chemistry and life Science Xiangnan University Chenzhou 423000 P. R. China

[Sm（C7H5O3）2（C4H6NO2S）]·2H2O was synthesized from the reaction of samarium chloride hexahydrate with salicylic acid and thioproline,and characterized by IR,elemental analysis and thermogravimatric *** standard molar enthalpies of the solutions of SmCl3·6H2O（s）,2[C7H6O3（s）],[C4H7NO2S（s）] and [Sm（C7H5O3）2·（C4H6NO2S）·2H2O（s）] in a mixed solvent of absolute ethyl alcohol,dimethyl formamide（DMF） and 3 mol/L HCl were,respectively,determined by calorimetry to be ΔsHm^Θ [SmCl3·6H2O（s）,298.15 K]=（-46.68±0.15） kJ/mol,ΔsHm^Θ [2C7H6O3（s）,298.15 K]=（25.19±0.02） kJ/mol,ΔsHm^Θ [C4H7NO2S（s）,298.15 K]=（16.20±0.17） kJ/mol and ΔsHm^Θ {[Sm（C7H5O3）2（C4H6NO2S）]·2H2O（s）,298.15 K}=（-81.24±0.67） kJ/*** enthalpy change of the reaction SmCl3·6H2O（s）＋2C7H6O3（s）＋C4H7NO2S（s）=[Sm（C7H5O3）2（C4H6NO2S）]·2H2O（s）＋3HCl（g）＋4H2O（l） was determined to be ΔrHm^Θ =（123.45±0.71） kJ/*** the data in the literature,the standard molar formation enthalpy of [Sm（C7H5O3）2（C4H6NO2S）]·2H2O（s） was estimated to be Δf Hm^Θ {[Sm（C7H5O3）2（C4H6NO2S）]·2H2O（s）,298.15 K}=（-2912.03±3.1） kJ/mol through Hess＇ law.

关键词： Samarium chloride hexahydrate Salicylic acid Thioproline Standard molar formation enthalpy

An approach for evaluating fire resistance of high strength Q460 steel columns

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Frontiers of Structural and Civil Engineering 2014年第1期8卷 26-35页

作者： Wei-Yong WANG guo-qiang li Bao-lin YU School of Civil Engineering Chongqing University Chongqing 400045 China State Key Laboratory for Disaster Reduction in Civil Engineering School of Civil Engineering Tongji University Shanghai 200092 China Department of Civil and Environmental Engineering Michigan State University East Lansing M1 48824 USA

To develop a methodology for evaluating fire resistance of high strength Q460 steel columns, the load bearing capacity of high strength Q460 steel columns is investigated. The current approach of evaluating load bearing capacity of mild steel columns at room temperature is extended to high strength Q460 steel columns with due consideration to high temperature properties of high strength Q460 steel. The critical temperature of high strength Q460 steel column is presented and compared with mild steel columns. The proposed approach was validated by comparing the predicted load capacity with that evaluated through finite element analysis and test results. In addition, parametric studies were carried out by employing the proposed approach to study the effect of residual stress and geometrical imperfections. Results from parametric studies show that, only for a long column （slenderness higher than 75）, the magnitude and distribution mode of residual stress have little influence on ultimate load bearing capacity of high strength Q460 steel columns, but the geometrical imperfections have significant influence on any columns. At a certain slenderness ratio, the stability factor first decreases and then increases with temperature rise.

关键词： high strength Q460 steel load bearing capacity temperature

Magnetic Energy of Force-Free Fields with Detached Field lines

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Chinese Journal of Astronomy and Astrophysics 2003年第6期3卷 555-562页

作者： guo-qiang li and You-Qiu HuSchool of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026 School of Earth and Space Sciences University of Science and Technology of China Hefei 230026

Using an axisymmetrical ideal MHD model in spherical coordinates, we present a numerical study of magnetic configurations characterized by a levitating flux rope embedded in a bipolar background field whose normal field at the solar surface is the same or very close to that of a central dipole. The characteristic plasma β (the ratio between gas pressure and magnetic pressure) is taken to be so small (β = 10-4) that the magnetic field is close to being force-free. The system as a whole is then let evolve quasi-statically with a slow increase of either the annular magnetic flux or the axial magnetic flux of the rope, and the total magnetic energy of the system grows accordingly. It is found that there exists an energy threshold: the flux rope sticks to the solar surface in equilibrium if the magnetic energy of the system is below the threshold, whereas it loses equilibrium if the threshold is exceeded. The energy threshold is found to be larger than that of the corresponding fully-open magnetic field by a factor of nearly 1.08 irrespective as to whether the background field is completely closed or partly open, or whether the magnetic energy is enhanced by an increase of annular or axial flux of the rope. This gives an example showing that a force-free magnetic field may have an energy larger than the corresponding open field energy if part of the field lines is allowed to be detached from the solar surface. The implication of such a conclusion in coronal mass ejections is briefly discussed and some comments are made on the maximum energy of force-free magnetic fields.

关键词： Sun: magnetic fields - Sun: coronal mass ejections (CMEs) -methods: numerical

Images for diagnosis ：CD4＋CD56＋ hematodermic neoplasm in a child

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Chinese Medical Journal 2010年第3期 379-381页

作者： guo Xia li qiang ZHOU Chen-yan Department of Pediatric Hematology/Oncology West China Second University Hospital Sichuan University Chengdu Sichuan 610041 China

CD4＋CD56＋ hematodermic neoplasm （HN） is a rare, highly aggressive systemic neoplasm, which had been -described under various names including lymphoblastic lymphoma of natural killer （NK） phenotype, blastic NK cell lymphoma （BNK）, leukemic lymphoma of immature NK lineage and CD4＋CD56＋ HN. This malignancy is mainly involved in elderly people and usually a rapidly fatal disease, since consistently effective treatments have not yet been developed. It is relatively rare in children Herein we report a boy with CD4＋CD56＋ HN.

关键词： CD4+CD56+ hematodermic neoplasm blastic natural killer cell lymphoma children

Two new diterpene alkaloids from the South China Sea Sponge Agelas aff. nemoechinata

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Chinese Chemical Letters 2016年第7期27卷 1048-1051页

作者： Tao li Bin Wang Nicole J.de Voogd Xu-li Tang Qi Wang Mei-Jun Chu Ping-lin li guo-qiang li Marine Science and Technology College Zhejiang Ocean University Zhoushan 316022 China School of Food and Pharmacy Zhejiang Ocean University Zhoushan 316022 China C National Museum of Natural History 2300 RA Leiden Netherlands College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China School of Medicine and Pharmacy Ocean University of China Qingdao 266003 China

Two new N-methyladenine-containing diterpenes,nemoechines F（l）and G（2）,were isolated from the South China Sea sponge Agelas *** structures were assigned on the basis of spectroscopic *** 2 showed weak activity aga... 详细信息

关键词： South China Sea Marine sponge Agelas Diterpene alkaloids Cytotoxic