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Transmission spectra characteristics of 1D photonic crystals with complex dielectric constant

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Rare Metals 2011年第2期30卷 150-154页

作者： GAO Yingjun CHEN Haibo QIU Hongguang LU Qianghua HUANG Changgao College of Physical Science and Engineering Guangxi University Nanning 5300041 China center oflnternational materials and {2. Chinese Academy of Science Shenyang 110016 China

The characteristics of photonic forbidden bands, transmission gain and absorption of one-dimensional （ID） dual-periodical photonic crystals （PC） with a complex dielectric layer were studied by using the optical transfer matrix （TM） method. The results show that the photonic band gap （PBG） of this structure is enlarged and many transmission resonance peaks appear in PBG. Large transmission gain for transmission peaks is obtained if the imaginary part of dielectric constant is negative. With the increase of the absolute value of the imaginary part, the transmission gain increases firstly and the transmittance gain gets to an apex. The imaginary parts of dielectric constant corresponding to transmission gain apex are different according to wavelength. However, the transmission ratio of resonance peaks is less than 1 if the imagi- nary part of dielectric constant is positive. The properties might be used to design multi-narrow-channel band filters and optical amplification devices synchronously.

关键词： photonic crystals one dimensional dielectric properties dielectric constant photonic band gap

Effects of icosahedral phase formation on the microstructure and mechanical improvement of Mg alloys:A review

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Progress in Natural Science:materials international 2012年第5期22卷 364-385页

作者： D.K.Xu,E.H.Han State Key Laboratory for Corrosion and Protection,Institute of Metal Research,chinese academy of {2.,62.Wencui Road,shenyang 110016,China State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences 62 Wencui Road Shenyang 110016 China

Icosahedral phase(I-phase) is a relatively excellent strengthening phase in Mg *** on their volume fraction,the yield strength of Mg-Zn-Y-Zr alloys can vary from 150 to 450 MPa at room ***,the formation of I-phase has been considered as one of the most effective methods for developing high strength lightweight Mg alloys for automotive and aerospace *** this review article,a series of research work about I-phase containing Mg alloys have been systematically investigated including I-phase formation mechanism and their effects on mechanical properties of Mg *** emphases have been given to:(1) Structure of I-phase and its orientation relationship with the a-Mg matrix.(2. Influence of alloying elements and solidification conditions on I-phase formation.(3) Effects of I-phase on microstructural evolution and mechanical improvement of Mg-Zn-Y-(Zr) ***,the applications of I-phase for the mechanical improvement of other Mg alloys such as AZ91 and super-lightweight Mg-Li alloys are also reviewed.

关键词： Icosahedral phase Mg alloys Mechanical properties Microstructural evolution

Electronic structure of edge dislocation of core-doped Ti in Fe

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Progress in Natural Science:materials international 2004年第6期 15-20页

作者： DANG Hongli 1 *,WANG Chongyu 1,2.3 and SHU Xiaolin 1(1. Central Iron and Steel Research Institute,Beijing 100081,China 2. Department of physics,Tsinghua University,Beijing 100084,China 3. international {2. for materials physics,Academica,shenyang 110016,China) Central Iron and Steel Research Institute，Beijing 100081，China Central Iron and Steel Research Institute，Beijing 100081，China Department of physics，Tsinghua University，Beijing 100084 China international center for {2. physics，Academica，shenyang 110016，China

The electronic structure of an edge dislocation doped Ti lying in the (001) plane with Burgers Vector along [100] direction in body-centered cubic iron is investigated using the first principles discrete variational method (DVM) based on the density-functional theory. The binding energy,impurity formation energy,interatomic energy,Mulliken orbital populations and charge density difference are presented in this paper. By calculating the binding energy of the clean dislocation system and the Ti-doped system,it is found that the binding energy of Ti-doped dislocation system is lower than that of the clean dislocation system,which implies that the Ti-doped dislocation system is more stable than the clean dislocation system. The calculated result of the impurity formation energy predicts the trapping effect of dislocation core for Ti,which shows that Ti atom prefers to occupy the place at the dislocation core. The calculated results of the interatomic energy and the difference charge density of dislocation doped Ti system indicate that the stronger bonding formed between the Ti impurity and its neighbor Fe atoms will affect the mechanical property of edge dislocation. Considering the influence of Ti on the electronic structure and the energies,we can predict that the trace Ti in transition metal Fe with dislocation defect can give a significant contribution to the solid solution hardening effects and will influence the mechanical property of materials.

关键词： edge dislocation doping effect electronic structure.

Stabilization effects of third element on CaCu5 type derivatives of rare-earth transition-metal intermetallics

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Progress in Natural Science:materials international 2002年第2期 3-12页

作者： LIANG Jingkui, LIU Quanlin, HUANG Feng, RAO Guanghui and CHEN Xiaolong( Institute of physics and center for Condensed Matter physics, chinese academy of sciences, Beijing 100080, China international center of Material physics, chinese academy of sciences, shenyang 110015, China)

Part of the results of the key project "Search for novel rare-earth functional materials" supported by the National Natural Science Foundation of China is reviewed. In combination with reports in literature, the effects of the third element M on the formation and stability of La2.Co, M)17, R(Fe, M)12.and R3(Fe, M)2. intermetallic compounds are discussed by considering mixing enthalpy of M with rare-earth, Fe and Co, and atomic radius, electronegativity and electronic configurations, etc. It is concluded that the mixing enthalpy and atomic radius dominate the preferential sites and the minimum amount of M required to stabilize a structure, which ultimately affect the magnetic properties of a compound prominently. This review should provide some heuristic hints for exploiting novel rare-earth transition metal functional materials and for improving their performance.

关键词： La2.Co M)17 R(Fe M)12 Rs(Fe M)2. crystal structure magnetic properties.

块状LaNi_5基纳米合金的正电子湮灭研究

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中国稀土学报 2003年第3期21卷 299-302页

作者：隋郁熊良钺龙期威苏文辉哈尔滨工业大学理学院应用物理系凝聚态科学与技术研究中心黑龙江哈尔滨150001 中国科学院国际材料物理中心

利用高温高压技术,在不同的压力和温度(～4.5GPa,～800℃)下将LaNi5基快淬合金粉直接压制成了块状纳米晶合金。X射线衍射分析表明,高压使其晶粒内部发生了明显的压致晶粒碎化,其平均晶粒尺寸在4.5GPa下从75.5nm降至2..6nm。利用正电子... 详细信息

利用高温高压技术,在不同的压力和温度(～4.5GPa,～800℃)下将LaNi5基快淬合金粉直接压制成了块状纳米晶合金。X射线衍射分析表明,高压使其晶粒内部发生了明显的压致晶粒碎化,其平均晶粒尺寸在4.5GPa下从75.5nm降至2..6nm。利用正电子湮灭技术研究了这种晶粒碎化效应对纳米合金内部缺陷结构的影响。测试结果表明,在高温高压的作用下,由于界面上原子的迁移和弛豫加剧,导致晶界上尺寸较大的微孔隙缺陷逐渐转化为尺寸较小的自由体积缺陷,使得纳米合金的致密度逐渐增强,显微硬度逐渐升高,从而在高温高压下得到致密的块状纳米合金材料。

关键词：凝聚态物理学压致碎化 LaNi5基合金纳米固体正电子湮灭稀土

A Model of Dynamic Recrystallization in Alloys during High Strain Plastic Deformation

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Journal of materials Science & Technology 1999年第5期15卷 435-438页

作者： Qiang LI and Yongbo XU(State Key Laboratory for Fatigue and Fracture of materials, Institute of Metal Research, chinese academy of sciences,{2. 110015, China) To whom correspondence should be addressed Present address: Analysis Cener, School of Mater State Key Laboratory for Fatigue and Fracture of materials Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China Analysis Cener School of Materials Tianjin University Tianjin 300072 China international center of {2. physics Chinese Academy of Sciences Shenyang 110015 China Laboratory for Non-linear Mechanics of Continuous Media Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Recrystallized grains, less than 2.0 nm in diameter were observed in heavily shear zones of a high strength low alloy steel and a Ni-based alloy, and Also grain refinement, less than 3 μm in diameter was made in high purity aluminum by ECAE at ambient temperature. The experimental results showed that high strain rate and large deformation could induce dynamic *** on dislocation dynamics and grain orientation change enhanced by plastic deformation,a model for the recrystallization process is developed. The model is used to explain the ultra fine grains which are formed at a temperature still much lower than that for the conventional recrystallization

关键词： Figure A Model of Dynamic Recrystallization in Alloys during High Strain Plastic Deformation

改进注浆法制备(ZrO_2._(0.92.(Y_2._3)_(0.08)电解质薄管的电学性能及应用

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中国稀土学报 2002年第1期20卷 16-21页

作者：贺天民吕喆刘江裴力曲志刚苏文辉吉林大学物理系中国科学院国际材料物理中心辽宁沈阳110015

用改进注浆法制备出长度为 2.2.6～ 2.6 6mm ,厚度为 0 4～ 0 9mm ,相对密度为 96 7%的 (ZrO2.) 0 .92.(Y2.O3 ) 0 .0 8电解质薄管 ,用SEM和交流阻抗谱研究了样品的微结构和电学性能 ,分析了烧结密度、晶粒和晶界对样品电学性能的影... 详细信息

用改进注浆法制备出长度为 2.2.6～ 2.6 6mm ,厚度为 0 4～ 0 9mm ,相对密度为 96 7%的 (ZrO2.) 0 .92.(Y2.O3 ) 0 .0 8电解质薄管 ,用SEM和交流阻抗谱研究了样品的微结构和电学性能 ,分析了烧结密度、晶粒和晶界对样品电学性能的影响 ,考察了用该电解质薄管组装的固体氧化物燃料电池的性能。结果表明 :样品的致密度随烧结温度的升高而逐渐增大 ,样品的微结构对其电学性能有强烈的影响 ,样品的电学性能随烧结密度的增加而增大 ,晶粒电导率和晶界电导率也随烧结温度升高而得以改善 ,16 5 0℃烧结的样品具有较好的烧结性能。单电池的最大开路电压和短路电流分别为 0 946V和 1 84A ,85 0℃时最大输出功率为 0 46W。

关键词：稀土改进注浆法 YSZ电解质薄管电学性能微结构固体氧化物燃料电池钇稳定化氧化锆制备

粘结超磁致伸缩Tb-Dy-Fe合金磁致伸缩性能的研究

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中国稀土学报 2003年第6期21卷 729-732页

作者：王博文李淑英闫荣格曹淑英翁玲河北工业大学磁技术与磁材料研究中心天津工业大学理学院天津300160

采用粘结方法制备了Tb1-xDyxFe2.状合金样品,经筛选确定了粘结材料的制备工艺,测试了粘结棒状合金样品的静态、动态磁致伸缩系数和磁机械耦合系数k33。结果表明,所制备的粘结棒状样品具有较高的磁致伸缩性能,且动态磁致伸缩参数d33和... 详细信息

采用粘结方法制备了Tb1-xDyxFe2.状合金样品,经筛选确定了粘结材料的制备工艺,测试了粘结棒状合金样品的静态、动态磁致伸缩系数和磁机械耦合系数k33。结果表明,所制备的粘结棒状样品具有较高的磁致伸缩性能,且动态磁致伸缩参数d33和磁机械耦合系数k33高于国外所报道的结果。

关键词：金属材料磁性材料磁致伸缩性能粘结 Terfenol-D 稀土元素 Tb-Dy-Fe合金粘结磁体制备工艺

Effect of fabrication parameters on the microstructure,in-plane anisotropy and magnetostriction of Fe-Ga thin films

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Rare Metals 2010年第6期29卷 583-588页

作者： WANG Bowen HUANG Wemnei CAO Shuying DU Yong HE Yuehui HUANG Baiyun Province-Ministry Joint Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability Hebei University of TechnologyTianjin 300130China international center for {2. physics Chinese Academy of SciencesShenyang 110015China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

The microstructure,in-plane anisotropy,and magnetic properties of Fe-Ga thin films were investigated by X-ray diffraction analysis,vibrating sample magnetometer,and capacitive cantilever *** in-plane induced anisotropy is well formed by the applied magnetic field during sputtering,and the anisotropy field Hk decreases with the sputtering power *** coercivity of Fe-Ga thin films decreases with increasing power when the sputtering power is less than 60 W and increases when the power is larger than 60 *** magnetostriction of the thin films reaches 66 × 10-6 at the sputtering power of 60 *** Fe-Ga films,which exhibit good field sensitivity,low coercivity and high magnetostriction,have been fabricated at the power of 60 W,and they can be used as the materials of magnetostrictive transducers.

关键词： metallic thin films magnetostriction magnetron sputtering anisotropy