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Experiments and Studies of Edge Plasma Radial Transport and Confinement Property on the HL-1M Tokamak 被引量:1
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作者 洪文玉 王恩耀 +1 位作者 潘宇东 李强 《Plasma Science and Technology》 SCIE EI CAS CSCD 2000年第4期347-356,共10页
This paper describes a Mach/Langmuir probe array with five pins and six pins, which can measure not only parallel flows and the flow perpendicular to the magnetic field but also the radial and the poloidal electric fi... This paper describes a Mach/Langmuir probe array with five pins and six pins, which can measure not only parallel flows and the flow perpendicular to the magnetic field but also the radial and the poloidal electric field E. arid E as well. Experimental measurements of the edge fluctuations, velocities of the toroidal, the poloidal flow and electric field have been carried out on both of SOL and the boundary region of HL-1M for Ohmic, biased H-mode, Lower Hybrid Current Drive (LHCD), Supersonic Molecular Beam Injection (MBI), Multi-shot Pellet Injection (MPI), Neutral Beam Injection (NBI), Ion Cyclotron Resonance Heating (ICRH) and Electric Cyclotron Resonance Heating (ECRH) discharges. The results show that the suppressions of the fluctuations are related to poloidal rotations produced by different discharge modes in the improved particle confinement property, simultaneously the change of the radial and poloidal electric field is generated and becomes more negative at the Tokamak plasma edge, and the sheared poloidal flow is related to the reduction in fluctuation level, and the poloidal velocity is mainly dominated by the E × B drift. 展开更多
关键词 LHCD Experiments and Studies of Edge Plasma Radial Transport and Confinement property on the HL-1M Tokamak ICRH ECRH HL
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ON WEAK CHEBYSHEV SUBSPACES AND THE PROPERTY AWC1 A SURVEY
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作者 A. Kamal (S.Q. University, Sultanate of Oman) 《Analysis in Theory and Applications》 2001年第4期77-89,共13页
The property awc1 was used by many authors to obtain results concerning approximation by elements of weak Chebyshev subspaces. In this paper the author studies this property in details, by collecting the scattered res... The property awc1 was used by many authors to obtain results concerning approximation by elements of weak Chebyshev subspaces. In this paper the author studies this property in details, by collecting the scattered results concerning it and by finding new ones. 展开更多
关键词 AWC ON WEAK CHEBYSHEV SUBSPACES Math AND THE property AWC1 A SURVEY
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Synthesis, Crystal Structure, Fluorescent Property and DFT Study of a Novel 1D Polymer [Zn(HMICD)(bpy)]_n·2nH_2O
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作者 郭瑞 刘广 +4 位作者 张杨 李朝阳 齐靖宇 刘宣文 苏娜 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第9期1420-1426,共7页
A new one-dimensional(1D) polymer, [Zn(HMIDC)(bpy)]n·2n H2O(1, H3MIDC = 2-methyl-imidazole-4,5-dicarboxylic acid, bpy = 2,2-bipyridine), has been solvothermally synthesized and characterized by single-cry... A new one-dimensional(1D) polymer, [Zn(HMIDC)(bpy)]n·2n H2O(1, H3MIDC = 2-methyl-imidazole-4,5-dicarboxylic acid, bpy = 2,2-bipyridine), has been solvothermally synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy, UV-vis spectrum and fluorescence measurements. Complex 1 crystallizes in orthorhombic system, space group Pbca with a = 14.404(3), b = 8.6900(17), c = 26.570(5) , V = 3325.8(11) -3, Dc = 1.700 g/cm-3, Mr = 425.70, Z = 8, F(000) = 1744, μ = 1.522 mm-(-1), the final R = 0.0421 and w R = 0.1018. The Zn(Ⅱ) ion is six-coordinated by O and N atoms from one HMIDC ligand, two O atoms from another HMIDC ligand and two N atoms from the bpy ligand. The HMIDC anion, which acts as a tetradentate ligand, chelates two Zn ions to form a one-dimensional(1D) zigzag chain structure. We analyzed the electronic structure and orbital energies of complex 1 by DFT methods, and the results are consistent with the UV-vis spectrum. And we also discussed the luminescent mechanism of complex 1 in detail. 展开更多
关键词 2-methyl-imidazole-4 5-dicarboxylic acid solvothermal synthesis 1D structure DFT fluorescence properties
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THE ELECTRIC PROPERTY OF SINGLET CARBENE AND ITS ISOELECTRONIC SYSTEM^1——Electrophilic and Nucleophilic Directions of an Atom in the Molecule
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作者 Jing Jiang LIU Lian De LU Department of Chemistry,Nankai University,Tianjin,300071 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第1期9-12,共4页
The electrostatic potential of carbene and nitrene,have been calculated by AB INITIO method with 6-31G** basis set,there are positive potential regions in the directions of vacant P orbitals,and negative regions in th... The electrostatic potential of carbene and nitrene,have been calculated by AB INITIO method with 6-31G** basis set,there are positive potential regions in the directions of vacant P orbitals,and negative regions in the directions of lone-pair electrons. Therefore,atoms in these molecules have different electric properties in different directions.The idea of electrophilic and nucleophilic directions of an atom in molecules should be introduced. 展开更多
关键词 ATOM Electrophilic and Nucleophilic Directions of an Atom in the Molecule THE ELECTRIC property OF SINGLET CARBENE AND ITS ISOELECTRONIC SYSTEM~1 ITS
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Effect of Trace Sc and Zr on the Mechanical Properties and Microstructure of A1 Alloy 2618 被引量:6
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作者 Kun YU, Songrui LI and Wenxian LI (Department of Materials Science and Engineering, Central South University of Technology, Changsha 410083, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第4期416-420,共5页
An experimental 2618(Al-Cu-Mg-Fe-Ni) alloy added with trace Sc and Zr was prepared by ingot metallurgy (IM) method. The aging behavior of the alloy was studied by Vickers hardness measurement at 200℃ and 300℃. and ... An experimental 2618(Al-Cu-Mg-Fe-Ni) alloy added with trace Sc and Zr was prepared by ingot metallurgy (IM) method. The aging behavior of the alloy was studied by Vickers hardness measurement at 200℃ and 300℃. and the tensile properties of alloy specimens were measured at 20℃, 200℃, 250℃ and 300℃. The microstructure was observed by using optical microscope, SEM and TEM. It was found that the addition of Sc and Zr to 2618 alloy resulted in a primary Al_3(Sc,Zr) phase which could refine the grain because it acts as nuclei of heterogeneous crystallization in the melt during solidification. The secondary Al_3(Sc,Zr) particles were full coherent with matrix and had obvious precipitation hardening effect. They also made the S' phase precipitate more homogeneous. So the strength of alloy increases at both ambient and elevated temperatures without a decrease of ductility. The ductile fracture of alloy occurs by microvoid nucleation, growth and coalescence, so the microvoid coalescence is the dominant fracture mechanism. 展开更多
关键词 Sc ZR Effect of Trace Sc and Zr on the Mechanical Properties and Microstructure of A1 Alloy 2618
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SYNTHESIS AND PROPERTIES OF 1-(2-IMIDAZOLYLAO)2-NAPHTHOL-4-SULFONIC ACID
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作者 Fu You PAN Sun Wei ZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第12期917-918,共2页
Synthesis of 1-(2-imidazolylazo)-2-naphthol-4-sulfonic acid is described including its physical and chemical properties and spectroscopic data. The reagent reacts with various transition metal ions to form water-solub... Synthesis of 1-(2-imidazolylazo)-2-naphthol-4-sulfonic acid is described including its physical and chemical properties and spectroscopic data. The reagent reacts with various transition metal ions to form water-soluble and colored chelates which can be decomposed by EDTA exoept cobalt chelate. Present method has good selectivity. 展开更多
关键词 SYNTHESIS AND PROPERTIES OF 1 IMIDAZOLYLAO)2-NAPHTHOL-4-SULFONIC ACID
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Electron Transport Properties of Two-Dimensional Si_1P_1 Molecular Junctions
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作者 Rui-Fang Gao Wen-Yong Su +1 位作者 Feng-Wang Wan-Xiang Feng 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第2期88-91,共4页
We focus on two new 21) materials, i.e., monolayer and bilayer silicon phosphides (Sil P1). Based on the elastic- scattering Green's function, the electronic-transport properties of two-dimensional monolayer and b... We focus on two new 21) materials, i.e., monolayer and bilayer silicon phosphides (Sil P1). Based on the elastic- scattering Green's function, the electronic-transport properties of two-dimensional monolayer and bilayer Au- Si1P1-Au molecular junctions are studied. It is found that their bandgaps are narrow (0.16eV for a monolayer molecular junction and 0.26 e V for a bilayer molecular junction). Moreover, the calculated current-voltage char- acteristics indicate that the monolayer molecular junction provides constant output current (20 hA) over a wide voltage range, and the bilayer molecular junction provides higher current (42 hA). 展开更多
关键词 Electron Transport Properties of Two-Dimensional Si1P1 Molecular Junctions SI
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Synthesis,Structure,and Surface Photo-electric Properties of a New Zn(Ⅱ)Coordination Complex Constructed from 2-(1H-benzotriazol-1-yl)acetic Acid and 1,10-Phenanthroline Ligands 被引量:2
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作者 李家明 史忠丰 何坤欢 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第1期135-142,共8页
A new binuclear Zn^Ⅱ coordination complex,Zn2(bta)(phen)2(Cl)3(1,Hbta = 2-(1Hbenzotriazol-1-yl)acetic acid and phen = 1,10-phenanthroline),has been synthesized and characterized by single-crystal X-ray diff... A new binuclear Zn^Ⅱ coordination complex,Zn2(bta)(phen)2(Cl)3(1,Hbta = 2-(1Hbenzotriazol-1-yl)acetic acid and phen = 1,10-phenanthroline),has been synthesized and characterized by single-crystal X-ray diffraction,IR spectroscopy,elemental,and photoluminescent analysis.Complex 1 crystallizes in triclinic system,space group P1 with a = 9.3040(19),b = 10.694(2),c =16.841(3) A°,α = 101.18(3),β = 105.77(3),γ = 91.72(3)°,V= 1575.8(5) A°3,C(32)H(22)Zn2Cl3N7O2,Mr =773.66,Dc = 1.631 g/cm^3,Z = 2,F(000) = 780,μ = 1.820 mm^-1,the final R = 0.1238 and wR =0.1131.X-ray diffraction analyses indicate that 1 displays two crystallographic independent Zn^Ⅱmetal centers with a distorted tetragonal pyramidal(ZnN4O) and a tetrahedral(ZnNCl3) geometries,respectively.The phen serves as a common N,N'-bidentate ligand,and the bta^- as a unique N,O-bridged ligand in 1.In the crystal,1 forms a stable 3D supramolecular architecture by trifurcated hydrogen bonding C-H…C1 interactions and C-H…π,π…π stacking.1 showed photo-electric conversion properties. 展开更多
关键词 photo-electric property zinc(Ⅱ) complex 2-(1H-benzotriazol-1-yl)acetic acid synthesis crystal structure
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GPCR/endocytosis/ERK signaling/S2R is involved in the regulation of the internalization,mitochondria-targeting and-activating properties of human salivary histatin 1
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作者 Dandan Ma Wei Sun +6 位作者 Cuicui Fu Kamran Nazmi Enno C.I.Veerman Richard T.Jaspers Jan G.M.Bolscher Floris J.Bikker Gang Wu 《International Journal of Oral Science》 SCIE CAS CSCD 2022年第3期334-348,共15页
Human salivary histatin 1(Hst1)exhibits a series of cell-activating properties,such as promoting cell spreading,migration,and metabolic activity.We recently have shown that fluorescently labeled Hst1(F-Hst1)targets an... Human salivary histatin 1(Hst1)exhibits a series of cell-activating properties,such as promoting cell spreading,migration,and metabolic activity.We recently have shown that fluorescently labeled Hst1(F-Hst1)targets and activates mitochondria,presenting an important molecular mechanism.However,its regulating signaling pathways remain to be elucidated.We investigated the influence of specific inhibitors of G protein-coupled receptors(GPCR),endocytosis pathways,extracellular signal-regulated kinases1/2(ERK1/2)signaling,p38 signaling,mitochondrial respiration and Na+/K+-ATPase activity on the uptake,mitochondria-targeting and-activating properties of F-Hst1.We performed a si RNA knockdown(KD)to assess the effect of Sigma-2 receptor(S2R)/Transmembrane Protein 97(TMEM97)—a recently identified target protein of Hst1.We also adopted live cell imaging to monitor the whole intracellular trafficking process of F-Hst1.Our results showed that the inhibition of cellular respiration hindered the internalization of F-Hst1.The inhibitors of GPCR,ERK1/2,phagocytosis,and clathrin-mediated endocytosis(CME)as well as siRNA KD of S2R/TMEM97 significantly reduced the uptake,which was accompanied by the nullification of the promoting effect of F-Hst1 on cell metabolic activity.Only the inhibitor of CME and KD of S2R/TMEM97 significantly compromised the mitochondria-targeting of Hst1.We further showed the intracellular trafficking and targeting process of F-Hst1,in which early endosome plays an important role.Overall,phagocytosis,CME,GPCR,ERK signaling,and S2R/TMEM97 are involved in the internalization of Hst1,while only CME and S2R/TMEM97 are critical for its subcellular targeting.The inhibition of either internalization or mitochondria-targeting of Hst1 could significantly compromise its mitochondria-activating property. 展开更多
关键词 GPCR/endocytosis/ERK signaling/S2R is involved in the regulation of the internalization mitochondria-targeting and activating properties of human salivary histatin 1 ERK
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Effects of A1 Additions on Microstructure and Mechanical Properties of MoSi_2
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作者 Jianlin LI Dongliang JIANG and Shouhong TAN(Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第6期578-580,共3页
The effects of Al additions on the microstructure and mechanical properties of MoSi2 have been studied. With the A1 additions from 2.5 wt pct to 5 wt pct, the siliceous grain boundary phase in hot pressed samples was ... The effects of Al additions on the microstructure and mechanical properties of MoSi2 have been studied. With the A1 additions from 2.5 wt pct to 5 wt pct, the siliceous grain boundary phase in hot pressed samples was eliminated because of the formation of Al2O3 particles. It was shown that Al and SiO2 reacted at 860℃. During the reaction, A1 atoms were mainly transferred to Al2O3 particles, and to some extent, diffused into MoSi2 grains. Both the toughness and strength of Al containing composites exceeded those of pure MoSi2 material. Bending strength and fracture toughness reach the highest value of 350 MPa, 4.05 MPa.m1/2, respectively, at ambient temperature when Al addition was of 3.5 wt pct. 展开更多
关键词 FIGURE MPa Effects of A1 Additions on Microstructure and Mechanical Properties of MoSi2
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Structures and Magnetic Properties of Europium-Transition Metal-Gallium Ternary Intermetallic Compounds with 1:3 Type
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作者 何强 郭永权 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第1期158-161,共4页
The crystal structures and magnetic properties of novel Eu TrGa3-r (T=Pd, It, Rh) in termetallic compounds are investigated by using powder x-ray diffraction and magnetic measurements. EuTrGa3-r crystallizes in orth... The crystal structures and magnetic properties of novel Eu TrGa3-r (T=Pd, It, Rh) in termetallic compounds are investigated by using powder x-ray diffraction and magnetic measurements. EuTrGa3-r crystallizes in orthorhombic structure with space group of Cmcm and Z = 4. There are four kinds of nonequivalent 4c crystal positions in EuTrGaa-r unit cell, which are occupied by 4Eu, 4GaⅠ, 4(GaⅡ, T) and 4GaⅢ, respectively. EuTrGa3-r ex- hibits the complex magnetic states in low-temperature regime, with the three-, two- and one-antiferromagnetic transitions occurring for T=Ir, T=Rh and T=Pd, respectively. It might be due to the Kondo effect: a localized antiferromagnetic interaction of the isolated impurity spins with the surrounding conduction electrons at low-temperature regime. 展开更多
关键词 Pd Ga Structures and Magnetic Properties of Europium-Transition Metal-Gallium Ternary Intermetallic Compounds with 1 Type Eu
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Hydrothermal Synthesis, Crystal Structure and Surface Photo-electric Properties of a New Nickel(Ⅱ) 3-D Metalorganic Framework Constructed from the Rigid 1,4-Bis(imidazol-1-yl) benzene Ligand
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作者 王爱荣 李家明 +2 位作者 史忠丰 何坤欢 高健 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第4期647-653,共7页
A new 3-D nickel(Ⅱ) metal-organic framework(MOFs) with formula [Ni(bib)_2(SO_4)]_n(1), where bib = 1,4-bis(imidazol-1-yl)benzene, has been synthesized and characterized by single-crystal X-ray diffraction... A new 3-D nickel(Ⅱ) metal-organic framework(MOFs) with formula [Ni(bib)_2(SO_4)]_n(1), where bib = 1,4-bis(imidazol-1-yl)benzene, has been synthesized and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and surface photovoltage spectroscopy(SPS). Complex 1 crystallizes in monoclinic system, space group C2/c with a = 19.5988(6), b = 9.7531(3), c = 11.8146(4) ?, β = 96.185(3)°, V = 2245.20(12) ?~3, C_(24)H_(20)N_8NiO_4S, M_r = 575.25, D_c = 1.702 g/cm^3, Z = 4, F(000) = 1184, μ = 1.011 mm-1, the final R = 0.0293 and w R = 0.0702. X-ray diffraction analyses indicated that the center Ni^(2+) ion is six-coordinated with an O_2N_4 donor set of two μ_2-SO_4^(2–) and four bib ligands, resulting in an ideal octahedral geometry. Topological analysis on complex 1 considers each Ni^(2+) as a 6-connected node, while bib and sulfate ion as linkers, giving an α-Po topology with short Schl?fli symbol 412·63. In the crystal packing, the components interact with pairs of intermolecular C–H×××O hydrogen bonds. The SPS of 1 indicates that there are positive response bands in the range of 300~600 nm showing photo-electric conversion properties. 展开更多
关键词 photo-electric property nickel(Ⅱ) complex 1 4-bis(imidazol-1-yl)benzene synthesis crystal structure
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Game Analysis for Intellectual Property Protection(IPP) of Multinational Corporations in the Context of R&D Internationalization
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作者 贺团涛 曾德明 《Journal of Donghua University(English Edition)》 EI CAS 2011年第1期109-114,共6页
In order to explore the impact relationship between intellectual property protection(IPP) system and technological innovation,a game model was constructed.The system of IPP is a set of game rules to protect the innova... In order to explore the impact relationship between intellectual property protection(IPP) system and technological innovation,a game model was constructed.The system of IPP is a set of game rules to protect the innovation under the background of R&D internationalization.Only when the main parties abide by the system of intellectual property,can the self-interest and collective interest of the two sides be maximized.The government must strengthen the penalties for intellectual property right(IPR) violations,reduce the cost of IPP declaration,reduce the cost of the innovator's own rights protection,and increase the cost of imitate behavior of IPR. 展开更多
关键词 R&D internationalization transnational corporations(TNCs) intellectual property protection(IPP) game1
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Hydrothermal Synthesis,Crystal Structure and Properties of a Novel 3D Metal-organic Coordination Polymer with Helical Chains Based on 5-(Imidazol-1-ylmethyl)isophthalic Acid
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作者 李付安 杨维春 +1 位作者 苗许 李松田 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第3期421-427,共7页
A novel 3D metal-organic coordination polymer with helical chains based on a flexible 5-(imidazol-1-ylmethyl)isophthalic acid(H_2L) as a main ligand and 1,2-bis(4-pyridyl)ethane(bpa) as a N-containing ancillar... A novel 3D metal-organic coordination polymer with helical chains based on a flexible 5-(imidazol-1-ylmethyl)isophthalic acid(H_2L) as a main ligand and 1,2-bis(4-pyridyl)ethane(bpa) as a N-containing ancillary ligand,[Cd L(bpa)_(0.5)]_n(1),has been obtained under hydrothermal conditions and characterized by elemental analysis,powder X-ray diffraction(PXRD),IR,thermal gravimetric analyses(TGA) and single-crystal X-ray diffraction.It crystallizes in monoclinic,space group P2_1/c with a = 10.984(2),b = 10.1829(12),c = 17.782(3) A,β = 123.156(11)o,V = 1665.1(5) A^3,Z = 4,Mr = 448.72,Dc = 1.790 g/cm^3,Rint = 0.0871,F(000) = 892,the final R = 0.0687 and w R = 0.1294 for 2920 observed reflections(I 〉 2σ(I)).In complex 1,the L^2- anions connect Cd(Ⅱ) ions to form two-dimensional metal-organic layers(Cd_2L_2)n,in which the 1D helical chains(Cd-L)_n are alternately arranged in a right-and left-handed sequence.These layers are further linked to build a 3D network by the bpa ligand.In addtion,photoluminescent properties for 1 are also investigated. 展开更多
关键词 cadmium 5-(imidazol-1-ylmethyl)isophthalic acid PXRD luminescent properties
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Synthesis and electrochemical performance of micro-nano structured Li Fe1-xMnxPO4/C(0≤x≤0.05)cathode for lithium-ion batteries
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作者 Chunyang Li Guojun Li Xiaomei Guan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第3期923-929,共7页
Micro-nano structured Li Fe(1-x)MnxPO4/C(0≤x≤0.05)cathodes were prepared by spray drying,followed by calcination at 700°C.The spherical Li Fe(1-x)MnxPO4/C(0≤x≤0.05)particles with the size of 0.5 to5.0... Micro-nano structured Li Fe(1-x)MnxPO4/C(0≤x≤0.05)cathodes were prepared by spray drying,followed by calcination at 700°C.The spherical Li Fe(1-x)MnxPO4/C(0≤x≤0.05)particles with the size of 0.5 to5.0μm are composed of lots of nanoparticles of 20 to 30 nm,and have the well-developed interconnected pore structure.In contrast,when Mn doping content is 3 mol%(x=0.03),the Li Fe(0.97)Mn(0.03)PO4/C demonstrates maximum specific surface area of 31.30 m^2/g,more uniform pore size and relatively better electrochemical performance.The initial discharge capacities are 161.59,157.04 and 153.13 m Ah/g at a discharge rate of 0.2,0.5 and 1 C,respectively.Meanwhile,the discharge capacity retentions are~100%after 120 cycles.The improved electrochemical performance should be attributed to higher specific surface,smaller polarization voltage,and a high Li~+diffusion rate due to the micro-nano porous structure and lattice expansion produced by Mn doping. 展开更多
关键词 Li Fe1-xMnxPO4/C Spray drying Electrochemical property Micro-nano structure
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Synthesis and Properties of Non-isocyanate Crystallizable Aliphatic Thermoplastic Polyurethanes 被引量:2
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作者 LI Suqing DENG Yong +3 位作者 ZHAO Jingbo ZHANG Zhiyuan ZHANG Jnuying YANG Wantai 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第5期1275-1280,共6页
A simple non-isocyanate route synthesizing thermoplastic polyurethanes(TPUs) with good thermal and mechanical properties is described. Melt transurethane polycondensation of dimethyl 1,6-hexamethylene dicarbamate wi... A simple non-isocyanate route synthesizing thermoplastic polyurethanes(TPUs) with good thermal and mechanical properties is described. Melt transurethane polycondensation of dimethyl 1,6-hexamethylene dicarbamate with 1,4-butanediol and 1,6-hexanediol was conducted at different molar ratios under the catalysis of tetrabutyl titanate. A series of crystallizable non-isocyanate TPUs with high molecular weight were prepared. The TPUs were characterized by gel permeation chromatography, FT-IR, 1 H-NMR, differential scanning calorimetry, thermogravimetric analysis, wide angle X-ray diffraction, AFM, and tensile tests. The TPUs exhibited Mn ranging from 12 500 to 26 400 g/mol, Mw from 16 700 to 56 400 g/mol, Tm up to 151.4 °C, and initial decomposition temperature over 241.8 °C. Their tensile strength reached 42.99 MPa with a strain at break of 30.00%. TPUs constructed simply with butylene, hexylene, and urethane linkages were successfully synthesized through a non-isocyanate route. 展开更多
关键词 thermoplastic polyurethanes non-isocyanate route transurethane polycondensation properties dimethyl 1 6-hexamethylene dicarbamate
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Property(ω_1) and Single Valued Extension Property 被引量:1
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作者 Chen Hui SUN Xiao Hong CAO Lei DAI 《Journal of Mathematical Research and Exposition》 CSCD 2010年第6期1009-1014,共6页
In this note we study the property(ω1),a variant of Weyl's theorem by means of the single valued extension property,and establish for a bounded linear operator defined on a Banach space the necessary and sufficien... In this note we study the property(ω1),a variant of Weyl's theorem by means of the single valued extension property,and establish for a bounded linear operator defined on a Banach space the necessary and sufficient condition for which property(ω1) holds.As a consequence of the main result,the stability of property(ω1) is discussed. 展开更多
关键词 property(ω1 single valued extension property.
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Highly bioactive nano-hydroxyapatite/partially stabilized zirconia ceramics
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作者 WANG Qing-liang, GE Shi-rong, ZHANG De-kun College of Material Science and Engineering, China University of Mining and Technology, Xuzhou 221007, P.R. China 1 《Journal of Bionic Engineering》 SCIE EI CSCD 2004年第4期215-220,共6页
Nanocrystalline hydroxyapatite (HA) powders have been synthesized by precipitation using Ca(NO3)2 4H2O and? (NH4)2 HPO4 at room temperature and atmospheric pressure. Nanocomposites of HA and partially stabilized zirc... Nanocrystalline hydroxyapatite (HA) powders have been synthesized by precipitation using Ca(NO3)2 4H2O and? (NH4)2 HPO4 at room temperature and atmospheric pressure. Nanocomposites of HA and partially stabilized zirconia (HA/PSZ) were sintered at atmospheric pressure and 1300 for 2h in air. The preparation techniques, structure and me- chanical properties of these materials were characterized. The addition of nanosized PSZ reinforcing phase to HA may lead to an improvement of the macro and micro mechanical properties and not affect its biocompatibility and bioactivity. The bending strength, fracture toughness and nano-hardness were near to or greater than those for human cortical bone and human tooth (dentine and enamel). The composite was incubated in a fresh human plasma which confirmed the bioactivity of nanosized HA/PSZ materials. The bonding reaction between HA/PSZ ceramic and the plasma proteins was found, and he- matopoietic cell phosphatase (HCP) layers formed on surface of each composite incubated in human plasma for two weeks. The diameter of a single HCP globule was less than 100 nm. Furthermore, the precipitating mechanism investigation was carried out through a comparative experiment in this paper. 展开更多
关键词 bioactive ceramics HYDROXYAPATITE PSZ NANOINDENTATION mechanical properties 1
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Property (ω) for Operator Matrices
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作者 TIAN Junhong CAO Xiaohong SUN Chenhui 《Wuhan University Journal of Natural Sciences》 CAS 2013年第4期343-347,共5页
In this note,property (ω)and property 1 (ω)are variants of Weyl’s theorem. By means of topological uniform descent, the sufficient and necessary conditions of a bounded linear operator defined on a Hilbert spac... In this note,property (ω)and property 1 (ω)are variants of Weyl’s theorem. By means of topological uniform descent, the sufficient and necessary conditions of a bounded linear operator defined on a Hilbert space that satisfies property 1 (ω) and property (ω)is studied. Moreover, property 1 (ω)and property (ω)of 2 2operator matrices are discussed as well. 展开更多
关键词 property 1 (ω) property (ω) topological uniform descent
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Property(ω) and Its Perturbations 被引量:1
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作者 Wei Juan SHI Xiao Hong CAO 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2014年第5期797-804,共8页
Abstract A Hilbert space operator T is said to have property (ω1) if σα(T)/σaw(T) π00(T), where σα(T) andσαw(T) denote the approximate point spectrum and the Weyl essential approximate point sp... Abstract A Hilbert space operator T is said to have property (ω1) if σα(T)/σaw(T) π00(T), where σα(T) andσαw(T) denote the approximate point spectrum and the Weyl essential approximate point spectrum of T respectively, and π00(T) ---- {λ∈ iso σ(T), 0 〈 dim N(T- λI) 〈 ∞}. Ifσα(T)/σαw(T) = π00(T), we say T satisfies property (w). In this note, we investigate the stability of the property (wi) and the property (w) under compact perturbations, and we characterize those operators for which the property (wi) and the property (w) are stable under compact perturbations. 展开更多
关键词 property (ω1 property (ω) compact perturbations
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