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Effect of pressure on thermostability of Fe_3B

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Chinese science Bulletin 1997年第21期42卷 1796-1798页

作者： YAO Bin, LIN Xiaomin, LI Fushan, SU Wenhui, DING Bingzhe and HU Zhuangqi1. Department of Physics, Jilin university, Changchun 13002., china 2. {2. key laboratory of Rapidly Solidified Non-equilibrium Alloys, Institute of Metal Research, Chinese Academy of sciences, Shenyang 110015, china Department of Physics Jilin University Changchun 130023 China

EFFECT of pressure on thermostability of metastable materials has been one of the importantsubjects in high-pressure research field. In the past ten odd years, much work has been donefor amorphous materials but a little for metastable crystalline materials, which indicates thatthe effect of pressure on the amorphous materials is closely related to their properties and crys-tallization mode, and is determined by two opposite influences of pressure on diffusion andnucleation, which make the thermostability of amorphous materials either increase or de-

关键词： pressure phase transition thermostability.

Phase evolutions of two kinds of co-precipitated indium-tin oxide pre-cursors by heat-treatment

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Rare Metals 2005年第2期24卷 146-150页

作者： CHENShuguang LIChenhui XIONGWeihao LIULangming WANGHui ZhnzhouSmelterGroupCo.Ltd. Zhuzhou412004China statekeyLabforPlasticFormingSimulation＆DieandMould{2. HnazhongUniversityofScienceandTechnologyWuhan430074China／／ZhnzhouSmelterGroupCo.Ltd.Zhuzhou412004China statekeyLabforPlasticFormingSimulation＆DieandMould{2. HnazhongUniversityofScienceandTechnologyWuhan430074China

Two kinds of indium-tin oxide (ITO) precursors, cubic indium hydroxide(In(OH)_3) and orthorhombic indium oxide hydroxide (InOOH), were prepared by a co-precipitationmethod. With the help of X-ray diffraction (XRD), thermo-gravimetric analysis (TGA) and differentialthermal analysis (DTA), phase evolutions from cubic In(OH)_3 and orthorhombic InOOH to cubic ITOsolid solution and rhombohedral ITO solid solution by heat-treatment had been comprehensivelyinvestigated. The transformation from cubic In(OH)_3 to cubic ITO solid solution started as low as150 deg C and ended at about 300 degC, and it exhibited an endothermic behavior. The transformationfrom orthorhombic InOOH to rhombohedral ITO solid solution started at 2.0 deg C and ended at about430 deg C. Moreover, this transformation was composed of two processes: the one was the dehydrationof InOOH exhibiting an endothermic behavior and the other was the transformation from dehydrationproducts to rhombohedral ITO solid solution exhibiting a strong exothermic behavior. RhombohedralITO solid solution was metastable in air and it would transform to cubic ITO solid solution byheat-treatment. The transformation from rhombohedral ITO solid solution to cubic ITO solid solutionstarted at 578 deg C and ended below 800 deg C, and it exhibited a weak exothermic behavior.

关键词： inorganic and nonmetallic materials crystal structure X-ray techniques indium-tin oxide

Phase-selection and metastable phase formation in highly undercooled eutectic Ni78.6Si2..4alloys

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Progress in Natural science:materials International 2006年第3期16卷 287-291页

作者： LU Yiping, YANG Gencang, YANG Changlin, WANG Haipeng and ZHOU Yaohe (state key {2. of Solidification Processing, Northwestern Polytechnical university, Xi'an 710072. china Department of Applied Physics, Northwestern Polytechnical university, Xi'an 710072. china) [a]state key {2. of Solidification Processing Northwestern Polytechnical University Xi'an China [b]Department of Applied Physics Northwestern Polytechnical University Xi'an China

A large undercooling (2.0 K) was achieved in eutectic Ni78.6 Si2..4 melt by the combination of molten-glass denucleation and cyclic superheating. The metastable phase formation process in the bulk undercooled eutectic Ni78.6 Si2..4 melts was investigated. With the increase of undercooling, different metastable phases form in eutectic Ni78.6 Si2..4 melts and part of these metastable phases can be kept at room temperature through slow post-solidification. Under large undercooling, the metastable phases β2.Ni3Si, Ni31Si12.and Ni3Si2.were identified. Especially, the Ni3Si2.phase was obtained in eutectic Ni78.6 Si2..4 alloy for the first time. Based on the principle of free energy minimum and transient nucleation theory, the solidification behavior of melts was analyzed with regard to the metastable phase formation when the melts were in highly undercooled state.

关键词： undercooling molten-glass metastable phase rapid solidification.

Catalytic nucleation of a meta-stable δ phase in phase-seeded undercooled Fe75Ni2. melts

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Progress in Natural science:materials International 2012年第3期22卷 258-262页

作者： Y.Z. Chen, X.H. Shi, F. Liu, G.C. Yang, Y.H. Zhou state key {2. of Solidification Processing, Northwestern Polytechnical university, Xi’an, Shaanxi 710072. china state key {2. of Solidification Processing Northwestern Polytechnical University Xi’an Shaanxi 710072 China

Undercooled Fe75Ni2. melts were phase-seeded by a high purity iron. It was found that above a critical undercooling, △Tc 135 K, a metastable δ phase (b.c.c) solidifies from the iron-seeded melts instead of a thermodynamically stable γ phase (f.c.c). While undercooling of the melt (△T) is below △Tc, solidification of the γ phase prevails in the iron-seeded melts. For the undercooled melts subjected to spontaneous nucleation, the γ phase always solidifies. After solidification, the as-solidified γ phase transforms completely to martensite; whereas the as-solidified metastable δ phase partially transforms to the γ phase, and then to martensite. The untransformed δ phase retains as a-ferrite particles in the microstructures. Based on the classical nucleation theory, catalytic nucleation of the metastable δ phase in the phase-seeded undercooled Fe75Ni2. melts was analyzed. It was quantitatively demonstrated that when △T>△Tc, the formation of the δ phase can be ascribed to a better catalytic effect of the iron on its nucleation than that on the nucleation of the γ phase.

关键词： Iron-nickel alloy Rapid solidification Microstructure Nucleation Undercooling

高温超导双晶结dc SQUID的I～V特性仿真研究

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系统仿真学报 2004年第7期16卷 1421-1424页

作者：漆汉宏田永君王天生郑东宁燕山大学亚稳材料制备技术与科学重点实验室秦皇岛066004 中科院物理所超导国家重点实验室北京100080

根据dcSQUID等效电路理论推导出描述dcSQUID特性的方程组,采用Matlab仿真工具软件对对称型高温超导双晶结dcSQUID进行仿真研究。仿真研究表明dcSQUID的输出电压是外磁通的周期性函数,其周期为一个磁通量子0。仿真研究的结果还为制备dcSQ... 详细信息

根据dcSQUID等效电路理论推导出描述dcSQUID特性的方程组,采用Matlab仿真工具软件对对称型高温超导双晶结dcSQUID进行仿真研究。仿真研究表明dcSQUID的输出电压是外磁通的周期性函数,其周期为一个磁通量子0。仿真研究的结果还为制备dcSQUID时,器件各参量的确定提供了有力的依据。

关键词：双晶结 dc SQUID 仿真 Matlab

Development of the entire roller inlayed block intelligence cold strip shape meter and its industrial application

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Baosteel Technical Research 2010年第S1期4卷 112-页

作者： LIU Hongmin,YU Bingqiang,YANG Lipo and PENG Yan Engineering Research Center of Rolling Equipment and Complete technology of Ministry of Education,state {2. laboratory of metastable materials science & technology,yanshan university,qinhuangdao 066004,{12.,china

The entire roller inlayed block intelligence cold strip shape meter is developed successfully in this paper,which can stably work chronically in the cold rolling workshop,the independent innovation of the key technology of cold strip shape measuring,the foreign technical monopoly and blockade are broken *** structural form which is different from the international popular segmented detection roller is put forward,the entire detection roller inlayed block is developed,a group of elastic blocks in that the sense organs are installed are inlayed in the radial symmetry rectangular grooves of the detection roller body,the entire roller structure is composed of elastic pieces and the roller body,the scratch of the strip surface due to different thermal expansion of the traditional detection roller measuring unit is avoided *** signal transmission form which is different form the international popular dry slip ring is put forward,the spray wet slip ring is developed,slip ring and detection roller can be taken down and installed as possibly as fast,so the maintain is convenient,while through the section auto-spray cleaning,lubrication and cooling, the service life is remarkable improved and the outside interference signal is *** signal processing form which is different form the international popular gathering card is put forward,the embedded DSP shape signal processing hardware system is developed,the electromagnet,temperature,humidity and vibration's interference of industry practice to shape transmission signal can be effectively avoided,which can guarantee the instantaneity and measured precision of shape measured *** shape signal processing software system whose function contains error compensation,pattern recognition,establishment of the target shape and the closed-loop control calculation is built,the shape meter' computer human interaction is friendly,and function of shape meter is strong,at the same time the intellectualized level

关键词： cold strip shape meter entire roller inlayed block detection roller spray wet slip ring digital signal processing hardware system intelligentized software system

CoxCu1-x复相纳米线阵列的制备及其磁性的研究

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物理学报 2008年第7期57卷 4527-4533页

作者：刘晓旭陈贵锋李养贤徐世峰吴光恒徐秋王鸿雁刘宝海师宏伟王冀霞赵郁海河北科技师范学院数理系秦皇岛066004 河北工业大学材料学院天津300130 中国科学院物理研究所北京凝聚态物理国家实验室北京100190

利用电化学沉积方法在同一种富Co2.溶液Co2./Cu2.=10∶1中,利用不同的沉积电位成功地制备了一系列不同成分(x=0.38—0.87)和复合相结构的CoxCu1-x纳米线阵列.发现随着纳米线中Cu含量的变化,CoxCu1-x纳米线的复相结构随之发生规律的变化... 详细信息

利用电化学沉积方法在同一种富Co2.溶液Co2./Cu2.=10∶1中,利用不同的沉积电位成功地制备了一系列不同成分(x=0.38—0.87)和复合相结构的CoxCu1-x纳米线阵列.发现随着纳米线中Cu含量的变化,CoxCu1-x纳米线的复相结构随之发生规律的变化,最终导致纳米线的磁性也随之规律的变化.随着纳米线中Cu含量的不断增加,一部分Cu与Co形成面心立方结构(fcc)的CoCu固溶体,减弱了磁晶各向异性与形状各向异性的竞争,从而提高样品的方形度;一部分Cu以fcc结构的Cu单质的形式存在于纳米线中,并随着Cu颗粒大小的不同分别起到破坏磁晶各向异性和钉扎畴壁的作用,从而增加纳米线的方形度和矫顽力.对比不同成分的样品,发现CoxCu1-x纳米线的方形度和矫顽力的最大值分别出现在Co75Cu2.和Co60Cu40中,并且由于其特殊的复相结构致使它们的值要好于相同直径的单相结构的结果.

关键词：纳米线电化学沉积磁性

Atomic stick-slip friction between commensurate self-assembled monolayers

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Progress in Natural science:materials International 2002年第7期 23-27页

作者： ZHANG Tao, ZHANG Jing, WANG Hui and HU Yuanzhong(The state key {2. of Tribology, Tsinghua university, Beijing 100084, china) The state key {2. of Tribology Tsinghua University Beijing 100084 China

The classical molecular dynamics simulations have been used to examine the compression and friction between commensurate selt-assembled monolayers (SAMs) on Au (111) . The friction force changes in a period corresponding to the geometric structure of sliding surfaces. The simulations reveal an ordered atomic stick-slip motion and discontinuous movements of diverse monomers, mainly head and tail groups. All of the head groups of the static film have 2.- 3 metastable positions (MPs). They oscillate around one of the MPs in stick phases and jump simultaneously to a new MP in slip phases. The tail groups of the sliding film are pulled forward together with opposite ones while sticking and jump forward half of the lattice constant relative to opposite ones while slipping. A complete vision of the motion of SAM chains is thereby built up and compared with the molecule behavior predicted by the Tomlinson model.

关键词： molecular dynamics simulation self-assembled monolayers sliding friction stick-slip.

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高温高压下氧化锌纳米晶的晶粒演化动力学

化学学报 2006年第16期64卷 1649-1653页

作者：邵光杰秦秀娟刘日平王文魁燕山大学亚稳材料科学与技术重点实验室燕山大学环境与化学工程学院秦皇岛066004 中国科学院物理研究所北京100080

用GS-1B型六面顶压机研究了ZnO纳米晶高温高压下的晶粒演化动力学,用MDI/JADE5X射线衍射仪(Cu靶)和XL30S-FEG场发射扫描电子显微镜对高压样品的相组成、晶粒尺寸及微观形貌进行了表征.实验发现300℃(包括300℃)以下,ZnO纳米材料中晶粒... 详细信息

用GS-1B型六面顶压机研究了ZnO纳米晶高温高压下的晶粒演化动力学,用MDI/JADE5X射线衍射仪(Cu靶)和XL30S-FEG场发射扫描电子显微镜对高压样品的相组成、晶粒尺寸及微观形貌进行了表征.实验发现300℃(包括300℃)以下,ZnO纳米材料中晶粒生长速率随着压力的升高先增大后减小,1～3GPa烧结体晶粒尺寸随着压力的升高而增大,4～6GPa烧结体晶粒尺寸随着压力的升高而减小.利用高压下晶粒生长速率方程求出1～3GPa,4～6GPa的激活体积分别为-5.82.9.66cm3/mol.400℃(包括400℃)以上,1～6GPa烧结体的晶粒尺寸随着压力的升高而不断增大.

关键词：氧化锌纳米晶高温高压晶粒演化动力学