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EFFECT OF MAGNETIC FIELD ON CALCITONIN GENE-RELATED PEPTIDE IN PERIODONTAL LIG AMENTS OF RATS

X. Chang , K. Qin and Y.L.Lu Orthodontic Department of Stomatology College , China Medical University , Sheny ang 110001 , China

金属学报(英文版)

proach change of CGRP with time in periodontal ligaments of rats in magnetic field, maxillae of 28 Wistar rats of 6 7 weeks were placed in magnetic fields of permanent magnets Nd 2 Fe 4 B. Changes of CGRP with t ime in maxillary periodontal ligaments of the rats were studied by immunohistochemistry. The result showed that: magnetic field had dynamic effect and some promotional effect on recove?E F F E C T O F M A G N E T I C F I E L D O N C A L C I T O N I N G E N E- R E L A T E D P E P T I D E I N P E R I O D O N T A L L I G A M E N T S O F R A T S X. Chang , K. Qin and Y. L. Lu Orthodontic Department of Stomatology College , China Medical University , Shenyang 110001 , China Manuscript received 24 June 1999 In order to approach change of C G R P with tim e in periodontal liga m ents of rats in m agneticfield , m axillae of 28 Wistar rats of 6 7 weeks w ere placed in m agnetic fields of per m anentm agnets Nd 2 Fe4 B. Changes of C G R P with tim e in m axillary periodontal liga ments of therats were stu died by i m m unohistoche mistry . The result sho wed that : m agnetic field had dy na m ic effect an d so m e pro motional effect on recovering and reconstruction of the periodontaltissues in it . This provided a better theoretical evidence for clinical use of per m anent m agnets .

关键词: per m anent m agnet Nd 2 Fe4 B , null , null , null

Yb0.005Y0.708Lu0.287VO4混晶的生长和材料性质

张炳涛 , 滕冰 , 钟德高 , 曹丽凤 , 李建宏 ,

人工晶体学报

采用提拉法生长出Ybb0.005Y0.708Lu0.287VO4晶体.在室温下,对Yb0.005Y0.708Lu0.287VO4晶体进行了XRPD测试,计算了晶格常数(a=b=0.7091 nm,c=0.6273 nm)和密度(4.826 g/cm3).对混晶的(100)面进行了腐蚀,腐蚀坑呈四棱锥形状.平均线膨胀系数α1=1.285×10-6 K-1,α3=7.030 ×10-6 K-1,温度在330.15 K和570.15 K之间变化时,比热为0.494 ~0.617 J/g·K.

关键词: 钒酸盐晶体 , 腐蚀坑 , 膨胀系数 , 比热 , 热导率

TEMPERATURE-DEPENDENCE OF THE MAGNETIC-PROPERTIES OF THE RARE-EARTH TRANSITION-METAL INTERMETALLIC LU2FE14C

Journal of Magnetism and Magnetic Materials

Magnetization curves of the ternary tetragonal compound Lu2Fe14C were measured in an extracting-sample magnetometer in the temperature range from 1.5 to 300 K. The temperature dependence of the magnetic properties of Lu2Fe14C is discussed.

关键词: anisotropy

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

COMPARATIVE STUDY OF CLINICALLY USED NiTi ORTHODONTIC WIRES

International Journal of Modern Physics B

The purpose of the study was to comparatively investigate two NiTi orthodontic wires. It is valuable to determine the phase transformation temperature and corrosion characteristics of the orthodontic wires to further study the shape memory effect and corrosion resistance properties. Optical microscope and EDX analysis were used for microstructure characteristics and composition analysis. Differential scanning calorimetry (DSC) was carried out to identify the phase transformation behavior of the two wires. Electrochemical tests in artificial saliva at 37 +/- 1 degrees C including polarization and electrochemical impedance spectroscopy (EIS) were used to assess the corrosion resistance and corrosion mechanism of the wires. It was found that the transformation temperature range of A-wire (imported) is narrower while the A(s) and A(f) are close to the body temperature, which is more suitable in the orthodontic operation at early stage. The corrosion current density of A-wire is lower than that of B-wire (domestically made) while the corrosion potential is higher. EIS test results indicated that the corrosion mechanism was the same. However, the oxide layer formed on the surface of A-wire is more protective.

关键词: NiTi orthodontic wire;shape memory effect;phase transformation;DSC;polarization;EIS;shape-memory alloys;transformation characteristics;phase-transformation;corrosion;behavior

A study of spin-hamiltonian parameters for Hf3+ ions in orthophosphate MPO4 (M = Sc, Lu, Y) crystals

Solid State Communications

The spin-Hamiltonian (SH) parameters (g factors g parallel to, g perpendicular to and hyperfine structure constants (177)A parallel to, (179)A parallel to, (177)A perpendicular to, (179)A perpendicular to) of 5d(1) ion Hf3+ in zircon-type orthophosphate MPO4 (M = Sc, Lu, Y) crystals are calculated from two microscopic SH theory methods, the perturbation theory method (PTM) and the complete diagonalization (of energy matrix) method (CDM). The calculated results show that when the high-order (i.e., the third-order rather than the conventional second-order) perturbation formulas in PTM are used, the calculated values from both PTM and CDM methods are not only close to each other, but also in good agreement with the experimental values. This suggests that the two microscopic SH theory methods based on crystal-field theory are effective to the explanations of SH parameters for 5d(n) ions in crystals. The covalence effect, the signs of constants A(i) (i = parallel to or perpendicular to) and the core polarization constants K obtained from the calculations are also discussed. (c) 2007 Elsevier Ltd. All rights reserved.

关键词: insulators;point defects;crystal and ligand fields;electron;paramagnetic resonance;electron-paramagnetic-res;phosphate single-crystals;epr parameters;cr3+ ions;laser;ruby

Y3+掺杂Ce∶Li6Lu(BO3)3闪烁体的发光性能研究

孙丹丹 , 潘尚可 , 任国浩 , 吴云涛 , 商珊珊 , 张国庆

无机材料学报 doi:10.3724/SP.J.1077.2013.12735

针对Ce:Li6Lu(BO3)3晶体有效原子序数(zeff)高的问题,采用低原子序数的Y3+离子部分置换晶体中的Lu3+离子.通过固相合成法制备了Ce:Li6Lu1-xYx(BO3)3(0≤x≤1)固溶体.X射线粉末衍射(XRD)分析表明,该系列固溶体结构与Li6Gd(BO3)3晶体相同,空间群为P21/c.其X射线激发发射(XSL)的发光强度随着Y3+的含量增加而降低,当x=0.5时,固溶体的有效原子序数与Li6Gd(BO3)3闪烁体相当,但XSL发光强度是其1.4倍.Ce:Li6Lu0.5Y0.5(BO3)3的XSL光谱和PL光谱都在400 nm附近出现Ce3+离子的特征峰,可拟合出361和419 nm两个发光分量,分别对应于Ce3+离子的激发态电子的5d1→2F5/2和5d1→2F7/2能级跃迁.Ce:Li6Lu0.5Y0.5(BO3)3固溶体的衰减时间比Ce:Li6Lu(BO3)3略长,为19.6 ns.当x=0.50~0.70时,Ce:Li6Lu1-xYx(BO3)3(0≤x≤1)闪烁体比较适合作为中子探测材料.

关键词: 固相合成 , Ce∶Li6LU1-xYx(BO3)3 , X射线激发发射谱 , PL光谱 , 衰减时间

LuxY1-xAl 3:Ce晶体中伴生(Lu,Y3 Al5O12:Ce相成因研究

丁栋舟 , 陆晟 , 潘尚可 , 张卫东 , 王广东 , 任国浩

无机材料学报 doi:10.3724/SP.J.1077.2008.00434

采用提拉法制备了LuxY1-xAlO3:Ce晶体样品, 通过XRD物相分析和成分分析, 并结合Lu2O 3-Al2O3二元体系相图以及LuxY1-x AlO3:Ce结构稳定性方面的分析与讨论, 结果表明: 随着熔体中Lu元素含量的增加, 熔体分层加剧, 析晶LuxY1-xAlO3:Ce相的熔体组成区间将向富Lu一侧偏移, 这使得晶体上部易伴生(Lu,Y)3Al5O12:Ce相; 而随着Lu元素含量的提高, LuxY1-xAlO3:Ce晶体的热稳定性降低, 氧空位的存在则使晶体的热稳定性进一步降低, 在接种过程中籽晶表面易发生相分解反应生成(Lu,Y)3 Al5O12:Ce和(Lu,Y) 4 Al2O9:Ce, 籽晶表面相分解产物(Lu,Y)3Al5O12:Ce提供了诱导析晶(Lu,Y)3Al5O12 :Ce相所需的晶核, 这使得晶体的外
表面处易伴生(Lu,Y)3Al5O12:Ce相. 调整配料组成使 n(Lu,Y)2O3 ): n (Al2O3)=1.17~1.00, 加大熔体内部和固液界面处的温度梯度以改善熔体对流、抑制熔体分层以及籽晶表面处的相分解等有助于高Lu元素含量LuxY1-xAlO3 :Ce晶体的获得.

关键词: 铝酸钇镥晶体 , perovskite , garnet , accompany

LuxY1-xAlO3:Ce晶体中伴生(Lu,Y)3Al5O12:Ce相成因研究

丁栋舟 , 陆晟 , 潘尚可 , 张卫东 , 王广东 , 任国浩

无机材料学报 doi:10.3321/j.issn:1000-324X.2008.03.004

采用提拉法制备了LuxY1-xAlOa:Ce晶体样品,通过XRD物相分析和成分分析,并结合Lu2O3-Al2O3二元体系相图以及LuxY1-xAlO3:Ce 结构稳定性方面的分析与讨论,结果表明:随着熔体中Lu元素含量的增加,熔体分层加剧,析晶LuxY1-xAlO3:Ce相的熔体组成区间将向富Lu一侧偏移,这使得晶体上部易伴生(Lu,Y)3Al5O12:Ce相;而随着Lu元素含量的提高, LuxY1-xAlO3:Ce晶体的热稳定性降低,氧空位的存在则使晶体的热稳定性进一步降低,在接种过程中籽晶表面易发生相分解反应生成(Lu,Y)3Al5O12:Ce和(Lu,Y)4Al2O9:Ce,籽晶表面相分解产物(Lu,Y)3Al5O12:Ce提供了诱导析晶(Lu,Y)3Al5O12:Ce相所需的晶核,这使得晶体的外表面处易伴生(Lu,Y)3Al5O12:Ce相.调整配料组成使n((Lu,Y)2O3):n(A12O3)=1.17~100,加大熔体内部和固液界面处的温度梯度以改善熔体对流、抑制熔体分层以及籽晶表面处的相分解等有助于高Lu元素含量LuxY1-xAlO3:Ce晶体的获得.

关键词: 铝酸钇镥晶体 , 钙钛矿 , 石榴石 , 伴生

Studies of the spin Hamiltonian parameters and the local structure of tetragonal Zr3+ Centers in orthophosphate MPO4 (M = Sc, Lu, Y) crystals

Zeitschrift Fur Naturforschung Section a-a Journal of Physical Sciences

The spin Hamiltonian parameters (g factors g(parallel to), g(perpendicular to) and hyperfine structure constants A(parallel to), A(perpendicular to)) of Zr3+ on the tetragonal M3+ (M = Sc, Lu, Y) sites of zircon-type orthophosphate MPO4 crystals are calculated by high-order perturbation formulas of d(1) ions in tetragonal symmetry. The crystal-field parameters are estimated by the superposition model and reasonable local structural data of impurity centers. The results show good agreement with the experimental values. It appears that in the case of size mismatch, the explanation of the spin Hamiltonian parameters of a paramagnetic impurity in crystals should take the impurity-induced local lattice relaxation into account.

关键词: EPR;spin Hamiltonian parameters;crystal-field theory;defect;structure;Zr3+;MPO4;(M = Sc, Lu, Y);electron-paramagnetic-res;d-orbital theory;superposition-model;single-crystals;cr3+ ions;ypo4;epr;lupo4;ruby;impurities

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