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(ba_(1-x)pb_x)tio_3半导体陶瓷的振动光谱研究  [PDF]
王国梅
武汉理工大学学报 , 1993,
Abstract: ?本文报道了ptc(ba_(1-x)pb_x)tio_3陶瓷的红外光谱和喇曼光谱。对室温时的红外吸收峰和喇曼散射峰的归属进行了分析,讨论了pb~(2+)的加入量对振动光谱的影响,以及在25~340℃范围内五种样品处于四方铁电相和立方顺电相时喇曼光谱与温度的关系。
居里点Tc高于300℃(Ba_(1-x)Pb_x)TiO_3系PTC陶瓷发热元件研制  [PDF]
陈宏金
福州大学学报(自然科学版) , 1991,
Abstract: 制造高居里点PTC热敏陶瓷用的高铅粉体掺杂瓷料,具有易分层、易挥发、不均匀等特点.通过设计合理配方、改进均化和细化粉体的加工、制定非等温速率的阶梯状快速升降温制度。获得性能和结构都较好的居里点Tc>300℃的PTC陶瓷发热元件。
Softening of high energy phonons by insulator-superconductor transition in Ba1-xKxBiO3 system  [cached]
H Khosroabadi,J Kobayashi,K Tanaka,SH Miyasaka
Iranian Journal of Physics Research , 2010,
Abstract: Single crystals of Ba1-xKxBiO3 compound for 0 < x
退化系统本征值、本征向量的摄动计算
吴善初
力学与实践 , 1989,
Abstract: 本文通过估计参数改变后相重(或相近)本征值对应的本征向量的可能方向,给出了退化系统本征值、本征向量的摄动计算方法.
退化系统本征值、本征向量的摄动计算  [PDF]
吴善初
力学与实践 , 1989, DOI: 10.6052/1000-0992-1989-011
Abstract: 本文通过估计参数改变后相重(或相近)本征值对应的本征向量的可能方向,给出了退化系统本征值、本征向量的摄动计算方法.
土壤质量诊断与评价理化指征及其应用  [PDF]
胡春胜
中国生态农业学报 , 1999,
Abstract: 介绍了澳大利亚科工组织建立的流域健康诊断指征体系的指征选择原则、13项诊断指征、指征评价方法与评价过程。并以此方法筛选和评价出太行山前平原农田土壤质量诊断的理化指征,提出了以经验性指征、形态学与物理学指征和化学指征综合评价该区土壤质量的指征体系。
ON THE SUPERCONDUCTING MECHANISM OF K3C60 AND Ba1-xKxBiO3

ZHANG LI-YUAN,ZHOU YUN-SONG,JIN GUANG-HAI,

中国物理 B , 1994,
Abstract: A superconducting mechanism for K3C60 and Ba1-xKxBiO3 has been suggested. This is the combining picture of the Cooper pair and the Ogg pair. Numerical calculations within the framework of this picture have been done for K3C60 and Ba1-xKxBiO3, and the overall consistency with the experimental data of superconducting properties is good.
手征负折射研究进展  [PDF]
董建峰,徐超,徐键
量子电子学报 , 2009,
Abstract: 负折射介质自从被实验实现起就因其所具有的新奇特性而引起了广泛的关注和研究。综述了通过手征方法实现负折射的研究进展,通过对手征负折射理论、手征结构的模拟计算和实验研究的概述,显示了用手征方法实现负折射的特点和优势,展现了该方法的潜在应用前景。
Phase Diagram of Ba1-xKxFe2As2  [PDF]
Sevda Avci,Omar Chmaissem,Duck-Young Chung,Stephan Rosenkranz,Eugene A. Goremychkin,John-Paul Castellan,Ilya S. Todorov,John A. Schlueter,Helmut Claus,Aziz Daoud-Aladine,Dmitry D. Khalyavin,Mercouri G. Kanatzidis,Raymond Osborn
Physics , 2012, DOI: 10.1103/PhysRevB.85.184507
Abstract: We report the results of a systematic investigation of the phase diagram of the iron-based superconductor, Ba1-xKxFe2As2, from x = 0 to x = 1.0 using high resolution neutron and x-ray diffraction and magnetization measurements. The polycrystalline samples were prepared with an estimated compositional variation of \Deltax <~ 0.01, allowing a more precise estimate of the phase boundaries than reported so far. At room temperature, Ba1-xKxFe2As2 crystallizes in a tetragonal structure with the space group symmetry of I4/mmm, but at low doping, the samples undergo a coincident first-order structural and magnetic phase transition to an orthorhombic (O) structure with space group Fmmm and a striped antiferromagnet (AF) with space group Fcmm'm'. The transition temperature falls from a maximum of 139K in the undoped compound to 0K at x = 0.252, with a critical exponent as a function of doping of 0.25(2) and 0.12(1) for the structural and magnetic order parameters, respectively. The onset of superconductivity occurs at a critical concentration of x = 0.130(3) and the superconducting transition temperature grows linearly with x until it crosses the AF/O phase boundary. Below this concentration, there is microscopic phase coexistence of the AF/O and superconducting order parameters, although a slight suppression of the AF/O order is evidence that the phases are competing. At higher doping, superconductivity has a maximum Tc of 38 K at x = 0.4 falling to 3 K at x = 1.0. We discuss reasons for the suppression of the spin-density-wave order and the electron-hole asymmetry in the phase diagram.
Electrical properties of resistive switches based on Ba1-xSr xTiO3 thin films prepared by RF co-sputtering
Márquez-Herrera, A.;Hernández-Rodríguez, E.;Cruz, M.P.;Calzadilla-Amaya, O.;Meléndez-Lira, M.;Guillén-Rodríguez, J.;Zapata-Torres, M.;
Revista mexicana de física , 2010,
Abstract: in this work, we propose the use of ba1-xsrxtio3(0 ≤ x ≤ 1) thin films for the construction of mim (metal-insulator-metal) heterostructures; and their great potential for the development of non-volatile resistance memories (reram) is shown. the deposition of ba1-xsrxtio3 thin films was done by the rf co-sputtering technique using two magnetron sputtering cathodes with batio3 and srtio3 targets. the chemical composition (x parameter) in the deposited ba1-xsrxtio3 thin films was varied through the rf power applied to the targets. the constructed mim heterostructures were al/ba1-xsrxtio3/nichrome. the i-v measurements of the heterostructures showed that their hysteretic characteristics change depending on the ba/sr ratio of the ba1-xsrxtio3 thin films; the ba/sr ratio was determined by employing the energy dispersive spectroscopy; sem micrographs showed that ba1-xsrxtio3 thin films were uniform without cracks or pinholes. additionally, the analysis of the x-ray diffraction results indicated the substitutional incorporation of sr into the batio3 lattice and the obtainment of crystalline films for the entire range of the x values.
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