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Interfacial Tunnel-type GMR in Granular Perovskite La1-xSrx MnO3

Ning ZHANG , Minyu ZENG , Weiping DING , Wei ZHONG , Youwei DU

材料科学技术(英文)

The spin-dependent interfacial tunneling and the corresponding tunnel-type magnetoresistance (TMR) have been observed in granular perovskite La1-xSrxMnO3 with x from 0.05 to 0.45. Study shows that the interfacial tunneling originates from the magnetic difference between the grain core and the surface, and the TMR stems from the field-induced change of magnetic order in the interface.

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A Coprecipitation Coating Synthesis of SiC/YAG Composites

Ning ZHANG , Hongqiang RU , Xudong SUN , Qingkui CAI

材料科学技术(英文)

The α-SiC in 0.5μm size powders were coated with Al2O3 and Y2O3 by a coprecipitation coating (CPC) method for fabrication of SiC/YAG composites. The same powder preparation was carried out by conventional mechanical mixing (MM) method for comparison. Two kinds of SiC/YAG composites were manufactured by pressureless sintering using the different powders, named CPC composite and MM composite thereafter respectively. It is shown that the CPC composite has the advantages of homogeneous distribution of YAG phase and of being sintered to high density at a low temperature, 100℃ lower than that of MM composite. The strength (573 MPa) and hardness (23.3 GPa) of the CPC composite are significantly higher than those (323 MPa and 13.5 GPa) of the MM composite, respectively.

关键词: Coprecipitation , null , null

Improving the electrochemical properties of natural graphite spheres by coating with a pyrolytic carbon shell

新型炭材料

Two kinds of modified natural graphite (MNG) spheres with a pyrolytic carbon shell on smooth or granular surface were obtained using fluidized bed chemical vapor deposition of acetylene by adjusting the reaction parameters. The core of the NING has a highly ordered graphite structure and the shell has a disordered structure. Compared with natural graphite (NG) spheres, MNG with a core-shell structure shows improved first cycling efficiency and cyclability. Especially, the NING spheres with a granular surface possess 84% retention of the first discharge capacity after 41 cycles, owing to effective decrease of the contact resistance and increase of contact area between the NING spheres.

关键词: fluidized bed chemical vapor deposition;core-shell structure;pyrolytic;carbon;modified natural graphite;lithium ion secondary battery;lithium-ion batteries;chemical-vapor-deposition;1st-cycle charge loss;anode material;encapsulated graphite;surface-area;infiltration;performance;improvement;pyrocarbon

Ion sputter erosion in metallic glass-A response to "Comment on: Homogeneity of Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass" by L-Y. Chen, Y-W. Zeng, Q-P. Cao, B-J. Park, Y-M. Chen, K. Hono, U. Vainio, Z-L. Zhang, U. Kaiser, X-D. Wang, and J-Z Jiang J. Mater. Res. 24, 3116 (2009)

Journal of Materials Research

The morphology of the dark and bright regions observed by transmission electron microscopy for the Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass strongly depends on the ion beam parameters used for ion milling. This indicates that the ion beam could introduce surface fluctuation to metallic glasses during ion milling.

关键词: room-temperature

Broer-Kaup-Kupershmidt方程的新精确解

杨立娟 , 杨琼芬 , 杜先云

量子电子学报 doi:10.3969/j.issn.1007-5461.2012.02.003

CK方法是求解非线性发展方程的一种有效的直接方法.利用推广的CK方法,求得(2+1)维Broer-Kaup-Kupershmidt方程的Backlund公式,从而获得方程的大量新的精确解,推广了Xu和Zhang的结果.

关键词: 非线性发展方程 , Broer-Kaup-Kupershmidt方程 , 精确解 , CK方法 , Backlund变换

Three-dimensional (3D) Ising universality in magnets and critical indices at fluid-fluid phase transition

Phase Transitions

Experimental data for critical exponents in some magnetic materials are compared with recent theoretical results on the three-dimensional (3D) Ising model, as derived by one of us (ZDZ) based on two conjectures [Z.D. Zhang, Conjectures on the exact solution of three-dimensional (3D) simple orthorhombic Ising lattices, Phil. Mag. 87 (2007), pp. 5309-5419]. It is found that critical exponents in some bulk magnetic materials indeed form a 3D Ising universality. Our attention is then focused on the critical indices at fluid-fluid phase transition. We suggest to use Zhang's exponent = 3/8 to fit the experimental data over the wider asymptotic region near the critical point of a fluid-fluid phase transition. The 3D Ising universality should exist for critical indices in a certain class of magnets and at fluid-fluid phase transition.

关键词: magnetically ordered materials;fluid-fluid;phase transitions;order-disorder effects;ferromagnetic curie temperature;liquid critical phenomena;x-ray-scattering;critical exponents;critical-point;coexistence;curves;binary-solutions;ionic-solutions;behavior;equation

Response to the Comment on 'Conjectures on exact solution of three-dimensional (3D) simple orthorhombic Ising lattices'

Philosophical Magazine

The error of Equation (15b) in my article [Z.D. Zhang, Phil. Mag. 87 (2007) p.5309] in the application of the Jordan-Wigner transformation does not affect the validity of the putative exact solution, since the solution is not derived directly from that equation. Other objections of Perk's comment [J.H.H. Perk, Phil. Mag. 89 (2009) p.761] are the same as those in Wu et al.'s comments [F.Y. Wu et al., Phil. Mag. 88 (2008) p.3093; p.3103], which do not stand on solid ground and which I have sought to refute in my previous response [Z.D. Zhang, Phil. Mag. 88 (2008) p.3097]. The conjectured solution can be utilized to understand critical phenomena in various systems, whereas the conjectures are open to rigorous proof.

关键词: 3D Ising model;exact solution;conjecture;critical phenomena;ferromagnetism;magnetic phase transition;model;analyticity

不同掺杂的钇系-123薄膜磁通特性

张鹰子 , 王志 , 向建勇 , 闻海虎

低温物理学报 doi:10.3969/j.issn.1000-3258.2005.z1.087

我们在磁场中分别测量了最佳掺杂的YBa2Cu3O7-δ、钙0.2掺杂的Y1-xCaxBa2Cu3O7-δ及钙0.5掺杂的Pr1-xCaxBa2Cu3O7-δ薄膜的电阻温度关系.利用最近Zhang et al. [Phys. Rev. B 71(2005), 052502 ]提出的热激活能的分析方法对薄膜的磁通特性进行了分析、比较与讨论.

关键词: Y-123薄膜 , 涡旋特性 , 激活能

1998 COMPREHENSIVE TABLE OF CONTENTS

中国腐蚀与防护学报

N。1Atmospheric Corrosivlty for Steels………………………………………………… .LIANG Caideng HO[I i。-tat(6)Caustic Stress Corrosion Cr。king of Alloy 800 Part 2.The Effect of Thiosul执e……………………………………… KONG De-sheng YANG Wu ZHAO Guo-zheng HUANG De.ltL。ZHANG Yu。。he CHEN She。g-bac(13)SERS slid E16CttOCh6iniC81 Stlldy Of Illhibit1Oli M6ch&tllsth Of ThlollY68 Oil ITOll ID H....

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