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On Structural Metaphors of Time in English and Chinese
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作者 郭巧懿 《科技信息》 2011年第22期I0187-I0187,共1页
According to the cognitive approach,metaphor is not only a matter of rhetoric language but a matter of thought,a point that is fully construed in Lakoff's conceptual metaphor theory.Based on the theory,this paper ... According to the cognitive approach,metaphor is not only a matter of rhetoric language but a matter of thought,a point that is fully construed in Lakoff's conceptual metaphor theory.Based on the theory,this paper analyzes the structural metaphors of time in English and Chinese. 展开更多
关键词 英语教学 教学方法 阅读教学 英语翻译
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EFFECTS OF Al CONTENT ON STRUCTURAL STABILITY AND MAGNETIC PROPERTIES OF Sm_2(Fe,Al)_(17) COMPOUNDS 被引量:1
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作者 Xu, Rengen Wang, Xinhua +4 位作者 Wu, Jianmin Pan, Hongge Chen, Changpin Wang, Qidong Dai, Lichi 《中国有色金属学会会刊:英文版》 EI CSCD 1999年第1期42-45,共4页
INTRODUCTIONItiswelknownthatSm2Fe17Nycompoundshavegoodintrinsicmagneticproperties[1].Becauseofthepoorstabi... INTRODUCTIONItiswelknownthatSm2Fe17Nycompoundshavegoodintrinsicmagneticproperties[1].BecauseofthepoorstabilityofSm2Fe17Nyat... 展开更多
关键词 sm 2Fe 17 AL HYDRIDE CURIE temperature structural STABILITY
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Structural and Magnetic Properties of Sm_3(Fe,Ti)_(29) and Sm_3(Fe,Ti)_(29)X_y (X=H, N) Compounds 被引量:1
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作者 Xinguo ZHAO, Zhidong ZHANG, Zhijun GUO, Wei LIU, Dianyu GENG and Baozhi CUI (Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第2期123-124,共2页
The alloy with nominal composition Sm_2(Fe0.94Ti0.06)17 is prepared by arc-melting, hydrogenation and nitrogenation processes. The Sm_2(Fe0.94Ti0.06)17 alloy has a single phase of Sm_3(Fe, Ti)29 with the Nd_3(Fe, Ti)... The alloy with nominal composition Sm_2(Fe0.94Ti0.06)17 is prepared by arc-melting, hydrogenation and nitrogenation processes. The Sm_2(Fe0.94Ti0.06)17 alloy has a single phase of Sm_3(Fe, Ti)29 with the Nd_3(Fe, Ti)29-type structure. The corresponding hydride phase with the same phase structure of the parent alloy was formed after a hydrogen decrepitation (HD) process at 300℃. The hydrogenation at 800℃ mainly shows a HDDR process. The HD and nitrogenation at 500℃ result in increasing the Curie temperature of the alloy by 72℃ and by 158℃ due to lattice expansions, respectively. The anisotropic and isotropic Sm_3(Fe. Ti)29N_y magnets are obtained after HD, HDDR and the consequent nitrogenation, respectively. The optimum magnetic properties of Sm_3(Fe, Ti)29N_y powders achieved in the above two processes are: (i) B_r=0;82 T, _iH_c=4.48 kA/cm. (BH)_max=54.3 kJ/m^3, (ii) B_r=0.68 T, _iH_c=8.14 kA/cm, (BH)max=66.4 kJ/m^3. 展开更多
关键词 TI and sm3 structural and Magnetic Properties of sm3 X=H X_y Fe Ti COMPOUNDS sm
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Structural and magnetic properties of Sm_2Fe_(17-x)Nb_x (x = 0-4) alloys prepared by HDDR processes and their nitrides 被引量:4
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作者 SUN Jibing CUI Chunxiang +3 位作者 ZHANG Ying LI lin GAO Jianxia LIU Yuling 《Rare Metals》 SCIE EI CAS CSCD 2006年第2期129-137,共9页
Sm2Fe17-xNbx (x = 0-4) powder was synthesized by HDDR treatment and nitrogenation. The effects of partial Nb substitution for Fe on the structural and magnetic properties of Sm2Fe17-xNbx alloys and their nitlides we... Sm2Fe17-xNbx (x = 0-4) powder was synthesized by HDDR treatment and nitrogenation. The effects of partial Nb substitution for Fe on the structural and magnetic properties of Sm2Fe17-xNbx alloys and their nitlides were investigated. It was seen that Sm2(Fe,Nb)17 phase exists in both annealed and HDDR-treated Sm2Fe17-xNbx alloys. However, its content is decreased with the increase in Nb substitution. In annealed alloys, Sm2(Fe,Nb)17 phase becomes unstable and will dissociate into SmFe2 and Fe-rich phases when x 〉 1.5. With HDDR-treatment, the Nb concentration in recombined Sm2(Fe,Nb)17 phase is decreased, and the content of Fe-rich phases is increased. Sm2Fe17-xNbx powder exhibits dendritic cracks and fine particles with a size of less than 300 nm. In nitrogenated alloys, N atoms mainly enter 2:17-type phase to form Sm2(Fe,Nb)17Ny. Partial Nb atoms in Sm2(Fe,Nb)17Ny phase will be released or excluded by nitrogen atoms. Fe-rich phases increase, and are followed by the amorphous Sm2(Fe,Nb)17Ny phase. Nb substitution for Fe with x = 0.5 and 1.0 in Sm2Fe17-xNbxNy powders increases the coercivity and remanence. But when x is greater than 2.0, Nb substitution will deteriorate the magnetic properties. 展开更多
关键词 magnetic materials sm-Fe-Nb-N alloys HDDR structural magnetic properties
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STRUCTURAL AND MAGNETIC PROPERTIES OF RTiFe_(11),RTiCo_(11) AND RTi(Fe_(1-x)Ni_x)_(11) COMPOUNDS(R=Nd,Sm,Gd,Tb,Dy,Ho,Er AND Y)
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作者 杨应昌 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第4期301-308,共8页
The crystallographic structure and intrinsic magnetic properties have been investigated in the RTiFe_(11), RTiCo_(11) and RTi(Fe_(1-X)Ni_X)_(11) compounds,where R represents Nd,Sm,Gd,Tb,Dy,Ho,Er and Y.Neutron diffract... The crystallographic structure and intrinsic magnetic properties have been investigated in the RTiFe_(11), RTiCo_(11) and RTi(Fe_(1-X)Ni_X)_(11) compounds,where R represents Nd,Sm,Gd,Tb,Dy,Ho,Er and Y.Neutron diffraction and Mossbauer spectra analyses have been used to study the nuclear and magnetic structure of these compounds.the Fe,Co,Ni and Ti atoms are found to exhibit strong site preference with f and j sites fa- voring Fe,Co and Ni atoms and the i site Ti atoms.Two different types of magnetic behavior were observed in the RTiFe_(11) and RTiCo_(11) compounds.In the former,the interatomic distance and the number of nearest neighbor atoms play essential roles.In particular,anomalous thermal expansion behavior is presented in RTiFe_(11).In the latter,the magnetic properties are essentially determined by the modification of the cobalt electronic configuration brought about by the transfer of rare earth conduction electrons to the transition 3d band.The saturation magnetization,Curie temperature and magnetocrystalline anisotropy data of RTiFe_(11), RTiCo_(11)and YTi(Fe_(1-X)Ni_X)_(11)are presented.A tempt to improve the intrinsic magnetic properties in RTiFe_(11)has been made,and the results are reported.On the basis of the crystalline field theory by using a single-ion model,the anisotropy constants and their temperature dependence of the R ions have been calcu- lated,which helps explain the spin reorientation observed in RTiFe_(11). 展开更多
关键词 structural AND MAGNETIC PROPERTIES OF RTiFe R=Nd sm Gd Tb Dy Ho Er AND Y RTiCo R x)Ni_x COMPOUNDS sm GD HO ND Ni DY
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Stress test and analysis based on SMS fiber structure with high sensitivity
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作者 张美芹 王冠军 +1 位作者 安永泉 王志斌 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第3期297-301,共5页
Single mode-multimode-single mode (SMS) sensor is widely used for parameters measurement, such as bending, dis-placement, temperature, strain, refractive index, etc. Generally, SMS sensor has advantages of simpl... Single mode-multimode-single mode (SMS) sensor is widely used for parameters measurement, such as bending, dis-placement, temperature, strain, refractive index, etc. Generally, SMS sensor has advantages of simple structure, low cost and easy layout, therefore it has become a research hotspot in recent years. In this paper, the multimode fiber with large core is used for manufacturing SMS structure with high sensitivity. Firstly, the multimode fiber with core/cladding diameters of 105/ 125 jitm has access to the system by means of single mode optical fiber. Secondly, SMS device structure is manufactured by welding the eccentric shaft of multimode optical fiber. Afterwards, mode interference effect and spectral response characteristics of the structure of single mode-multimode-single mode optical fiber are analyzed theoretically. Finally, with the help of a wide spectrum light source and a spectrum analyzer, the transmission spectra characteristics of SMS optical fiber with strain is tested. By observing the curve that the wave changes with stress, the sensitivity is calculated and it is consistent with theoretical value . 展开更多
关键词 smS optical fiber structure optical spectrum analyzer (OSA) amplified spontaneous emission stress test
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Synthesis and Crystal Structure of [Sm(4-Pyta)_3(H_2O)_2]_n (4-Pyta = 4-Pyridylthioacetate)
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作者 李文戈 潘兆瑞 +2 位作者 王作为 李一志 郑和根 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第1期78-82,共5页
A novel coordination polymer [Sm(4-Pyta)3(H2O)2]n has been synthesized by the hydrothermal reaction between 4-Pyta (4-Pyta = 4-pyridylthioacetate) and Sm(NO3)3. The structure was characterized by elemental ana... A novel coordination polymer [Sm(4-Pyta)3(H2O)2]n has been synthesized by the hydrothermal reaction between 4-Pyta (4-Pyta = 4-pyridylthioacetate) and Sm(NO3)3. The structure was characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space groupP1, with a = 9.100(2), b = 11.842(3), c = 12.183(3) A, α= 79.781(4), β= 74.124(4), γ = 841882(5)^o, V = 1241.6(5) A^3, Z = 2, Mr = 690.95, Dc = 1.84806 g/cm^3, F(000) = 686,μ = 2.669 mm^-1, the final R = 0.0388 and wR = 0.0808 for 4149 observed reflections with I 〉 2σ(I). The structural analysis shows that the complex exhibits a one-dimensional architecture. Intermolecular hydrogen bonding interactions are found in the complex molecules. 展开更多
关键词 4-pyridylthioacetate sm(Ⅲ) complex crystal structure
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A Comparative Study of Conceptual Structures of Metaphor and Metonymy from a Cognitive Perspective
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作者 ZHOU Li LI Man-yu 《Journal of Literature and Art Studies》 2021年第11期887-894,共8页
Metaphor and metonymy are viewed as two different figures of speech in traditional rhetoric,while,in cognitive linguistics,both are both conceptual,spontaneous,and unconscious human activities based on thinking and ba... Metaphor and metonymy are viewed as two different figures of speech in traditional rhetoric,while,in cognitive linguistics,both are both conceptual,spontaneous,and unconscious human activities based on thinking and basic experience in the human brain.In some sense,metaphor and metonymy can be a mode of thinking.A Concept is inseparable from perception and perception is inseparable from thinking.The basic composition of metaphor and metonymy is a concept.That is the way they are associated with.This paper aims to build conceptual structures of metaphor and metonymy from the micro perspective and probe into their working mechanisms.The author also lays out their distinctions in terms of basis,principles,span,and effectiveness through analyzing some examples extracted from literary works. 展开更多
关键词 metaphor METONYMY DIFFERENCE conceptual structure THINKING
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具有高热稳定性Sm^(3+)激活硼磷酸盐Na_(3)B_(6)PO_(13)橙红色荧光粉的发光特性
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作者 刘雨昕 胡倩 +6 位作者 粟茵 文麒麟 刘丽欣 覃钺 梁露露 张宏志 朱静 《材料导报》 EI CAS CSCD 北大核心 2024年第21期21-26,共6页
选用硼磷酸盐Na_(3)B_(6)PO_(13)作为基质,采用高温固相法合成Sm^(3+)激活橙红光荧光粉。利用X射线衍射、扫描电子显微镜和发光光谱等技术手段研究了荧光粉的晶体结构、微观形貌及发光性能。光谱测试结果表明,Na_(3)B_(6)PO_(13):9%Sm^(... 选用硼磷酸盐Na_(3)B_(6)PO_(13)作为基质,采用高温固相法合成Sm^(3+)激活橙红光荧光粉。利用X射线衍射、扫描电子显微镜和发光光谱等技术手段研究了荧光粉的晶体结构、微观形貌及发光性能。光谱测试结果表明,Na_(3)B_(6)PO_(13):9%Sm^(3+)的光谱强度最强,9%为最佳掺杂浓度,激发光谱峰值主要位于402 nm处,对应Sm^(3+)的^(6)H _(_(5/2))→^(4)F _(_(7/2))跃迁;发射峰主要位于599 nm与646 nm处,分别对应Sm^(3+)的^(4)G _(5/2)→^(4)H _(7/2)、^(6)H _(9/2)跃迁,而后随着掺杂浓度升高发生浓度猝灭现象,猝灭机制为电偶极-电四极相互作用。Na_(3)B_(6)PO_(13):9%Sm^(3+)的色坐标为(0.5591,0.4317),发光呈橙红色。发光热稳定性测试结果表明,样品在150℃时仍能保持室温下发光强度的90%。以上研究结果表明Na_(3)B_(6)PO_(13):Sm^(3+)可作为橙红色荧光粉候选材料。 展开更多
关键词 硼磷酸盐 sm 3+ 掺杂 橙红光 晶体结构
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INDO STUDIES ON THE ELECTRONIC STRUCTURE OF[Ln(CCl_3COO)_3·phen·C_2H_5OH]_2(Ln=Pr,Sm)
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作者 Nan DONC Long Guan ZHU Nian Ci WU Department of Chemistry,Hangzhou University,Hangzhou 310028 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第8期649-650,共2页
The electronic structure and chemical bonding of the title comp- lexes have been studied by an unrestricted INDO program made applicable for the lanthanoid compounds.The results indicated:(1)In coordinated bonds O-Ln ... The electronic structure and chemical bonding of the title comp- lexes have been studied by an unrestricted INDO program made applicable for the lanthanoid compounds.The results indicated:(1)In coordinated bonds O-Ln and N-Ln,5d orbitals of Ln have large contribution in all valence orbitals of Ln and 4f orbitals have very small contribution.(2)The covalent chara- cter and ionic character are almost equal in the chemical bond which is comparatively weak between phen,C_2H_5OH and Ln are mainly ionic with some covalent character. 展开更多
关键词 INDO STUDIES ON THE ELECTRONIC structurE OF[Ln CCl3COO PHEN Ln=Pr sm C2H5OH LN
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Musical Event Structure Metaphors in Beckett's Ghost Trio
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作者 Lihua Huang 《International Journal of Technology Management》 2014年第9期110-112,共3页
Samuel Beckett' s dramaticles are permeated with musical aesthetic thought, which is one of his unique writing styles. Exploration of such style is beneficial and conducive to deepen our understanding of the abstract... Samuel Beckett' s dramaticles are permeated with musical aesthetic thought, which is one of his unique writing styles. Exploration of such style is beneficial and conducive to deepen our understanding of the abstract and fragmented dramatic discourse. This thesis makes attempt to investigate musical aesthetic thought from the angle of the Event Structure Metaphor. 展开更多
关键词 Samuel Beckett musical aesthetic thought Event structure metaphor Ghost Trio
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SMS结构的光纤F-P腔压力传感器的实验研究 被引量:1
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作者 谢思豪 陶青 陈思远 《传感器与微系统》 CSCD 北大核心 2024年第1期56-58,61,共4页
对单模—多模—单模(SMS)结构的光纤法布里—珀罗(F-P)腔压力传感器进行了研究。从理论上分析了SMS光纤F-P腔压力传感器的工作原理;并用有限元软件仿真了传感器的压力灵敏度为0.36μm/MPa,熔接组成光纤F-P腔传感器。实验测试结果表明:... 对单模—多模—单模(SMS)结构的光纤法布里—珀罗(F-P)腔压力传感器进行了研究。从理论上分析了SMS光纤F-P腔压力传感器的工作原理;并用有限元软件仿真了传感器的压力灵敏度为0.36μm/MPa,熔接组成光纤F-P腔传感器。实验测试结果表明:灵敏度为0.0043/N,得到峰值点幅值与压力的相关性系数R2为98.80%,具有良好的线性关系,符合光纤压力传感器的设计要求。 展开更多
关键词 光纤压力传感器 单模—多模—单模结构 有限元仿真
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Synthesis and Crystal Structure of Tetra Benzoates Bridged Binuclear Sm(III) Complex
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作者 牛淑云 卜为民 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1999年第4期245-248,共4页
The binuclear complex Sm2(C12H8N2)2(C6H5COO)6 has been prepared and structurally analyzed by single crystal Xray diffraction. The complex crystallizes in the triclinic system, space group P1 , with a=10.833(2), b=11... The binuclear complex Sm2(C12H8N2)2(C6H5COO)6 has been prepared and structurally analyzed by single crystal Xray diffraction. The complex crystallizes in the triclinic system, space group P1 , with a=10.833(2), b=11.937(2), c=12.448(3) , = 104.97(3), = 93.63(3), = 113.27(3), V=1403.5 3, Dc=1.64g/cm3, =21.42cm-1, F(000)=690, Z=1, final R=0.037, Rw=0.077 for 4855 observed reflections I>2(I) and 5703 independent reflections. In the molecule, each Sm atom is coordinated by seven O atoms and two N atoms forming an irregular coordination polyhedron. 展开更多
关键词 SYNTHESIS crystal structure BENZOATE sm() complex
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基于模糊DEMATEL-ISM的矿山企业安全生产系统关键影响因素研究
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作者 高运超 李宏伟 +3 位作者 鲍乾 高洋平 袁奇 杨博 《煤炭技术》 CAS 2024年第10期198-202,共5页
探讨了我国矿山企业安全生产系统风险影响因素及相关影响机制,从人的行为、安全环境、安全管理、设备设施、科学技术5个层面建立了矿山企业安全生产系统风险因素体系。结合模糊集理论构建决策实验室分析和解释结构模型,对矿山企业安全... 探讨了我国矿山企业安全生产系统风险影响因素及相关影响机制,从人的行为、安全环境、安全管理、设备设施、科学技术5个层面建立了矿山企业安全生产系统风险因素体系。结合模糊集理论构建决策实验室分析和解释结构模型,对矿山企业安全生产系统风险因素的传递强度和传递结构进行可视化研究,量化矿山企业安全生产系统各风险因素之间的逻辑关系及其影响机制。计算结果表明,模糊集理论可以有效解决计算过程中存在模糊性和不确定性问题;安全监督管理和安全生产关键技术的影响度最高,分别为2.728和2.702;安全理论基础研究和安全投入费用被影响度较高,分别为2.443和2.321,属于重要风险因素;安全理论基础研究的中心值为4.987,属于根本因素,对矿山企业安全生产具有根本性和深远性的影响。 展开更多
关键词 决策试验与评估实验室 解释结构模型 模糊理论 矿山企业安全生产系统
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南岭花岗岩类岩石Sm、Nd同位素特征及岩石成因探讨 被引量:64
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作者 袁忠信 张宗清 《地质论评》 CAS CSCD 北大核心 1992年第1期1-15,共15页
根据南岭地区50个岩体79个样品,以及基底构造层岩石26个样品的Sin-Nd同位素特征值讨论了本区陆壳的形成时间及花岗岩类岩石的成因。本区陆壳形成于2101Ma以前,此后大约有2次大规模的地块增生。按照花岗岩类的t_(DM)、Sm/Nd、ε_(Nd)(t)... 根据南岭地区50个岩体79个样品,以及基底构造层岩石26个样品的Sin-Nd同位素特征值讨论了本区陆壳的形成时间及花岗岩类岩石的成因。本区陆壳形成于2101Ma以前,此后大约有2次大规模的地块增生。按照花岗岩类的t_(DM)、Sm/Nd、ε_(Nd)(t)值,以及区域大地构造特征,区内可划分出5个花岗岩分布区。不同地区的花岗岩类具有不同的Sm-Nd同位素特征值,同一地区的花岗岩类岩石及其基底构造层岩石具有相近的Sm-Nd同位素特征值,结合地质构造特征研究可以认为,不同地区花岗岩类的源岩主要就是该区的基底构造层岩石。后者对前者的分布、成因类型,甚至有关的成矿作用具有重要的控制作用。 展开更多
关键词 花岗岩 基底构造层 钐-钕同位素 成岩物质 成因 南岭地区
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Sm掺杂Bi_4Ti_3O_(12)陶瓷晶体结构及电性能的研究 被引量:6
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作者 王瑾菲 蒲永平 +3 位作者 杨公安 庄永勇 杨文虎 毛玉琴 《人工晶体学报》 EI CAS CSCD 北大核心 2009年第4期866-869,892,共5页
采用固相反应工艺制备了Sm3+掺杂层状结构无铅Bi4-xSmxTi3O12(x=0.00,0.25,0.50,0.75,1.00,1.25)介电陶瓷。利用XRD、SEM等测试方法研究了Sm掺杂量、烧结温度和保温时间对Bi4-xSmxTi3O12(BST)陶瓷晶体结构及电性能的影响。结果表明:所... 采用固相反应工艺制备了Sm3+掺杂层状结构无铅Bi4-xSmxTi3O12(x=0.00,0.25,0.50,0.75,1.00,1.25)介电陶瓷。利用XRD、SEM等测试方法研究了Sm掺杂量、烧结温度和保温时间对Bi4-xSmxTi3O12(BST)陶瓷晶体结构及电性能的影响。结果表明:所制备的Bi4-xSmxTi3O12陶瓷均具有单一正交相结构,BST陶瓷表面晶粒的显微形貌表现为随机排列的棒状结构。样品的铁电性能测试表明,Sm3+施主掺杂明显降低了BIT的电导率,随着Sm3+含量的增加,Sm3+逐渐有部分取代B位,由于Sm3+取代Ti4+大大降低了氧空位的浓度,使得氧空位对电畴的钉扎作用减弱,并且材料的剩余极化Pr也相应提高。 展开更多
关键词 固相反应 BI4TI3O12 sm掺杂 介电性能 晶体结构
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Sm掺杂对锐钛矿TiO_2电子寿命和红移影响的第一原理研究 被引量:6
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作者 侯清玉 张振铎 李聪 《功能材料》 EI CAS CSCD 北大核心 2012年第19期2599-2604,共6页
基于密度泛函理论平面波超软赝势方法,采用第一性原理对不同浓度Sm掺杂锐钛矿相TiO2超胞的结构优化、形成能、能带结构、态密度、差分电荷分布和光学性质进行了计算。结果表明Sm掺杂后锐钛矿相TiO2超胞的电子结构变化很大。在限定的浓... 基于密度泛函理论平面波超软赝势方法,采用第一性原理对不同浓度Sm掺杂锐钛矿相TiO2超胞的结构优化、形成能、能带结构、态密度、差分电荷分布和光学性质进行了计算。结果表明Sm掺杂后锐钛矿相TiO2超胞的电子结构变化很大。在限定的浓度范围内,掺杂浓度越小,形成能越小,掺杂越容易,电子寿命越长,带隙宽度越窄,吸收光谱红移越显著。计算结果与实验结果一致。 展开更多
关键词 sm掺杂 锐钛矿TIO2 电子结构 吸收光谱
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室温非水化学镀Sm-Fe-Ni-B合金的制备及性能研究 被引量:3
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作者 刘影 赵美峰 +2 位作者 王建朝 胡博 张贺 《华中师范大学学报(自然科学版)》 CAS 北大核心 2014年第1期71-74,共4页
具有软磁性能的合金已广泛应用于各行业领域.采用室温非水化学镀的方法制备了SmFe-Ni-B合金,并利用SEM、EDS和VSM考察了稀土Sm对镀层形貌,耐腐蚀性和磁性能等的影响.结果表明,稀土Sm的添加量在3g/L时对镀层的形貌和耐腐蚀性能都有较大... 具有软磁性能的合金已广泛应用于各行业领域.采用室温非水化学镀的方法制备了SmFe-Ni-B合金,并利用SEM、EDS和VSM考察了稀土Sm对镀层形貌,耐腐蚀性和磁性能等的影响.结果表明,稀土Sm的添加量在3g/L时对镀层的形貌和耐腐蚀性能都有较大的改善,对镀层的饱和磁化率和矫顽力有所提高. 展开更多
关键词 化学镀 sm-Fe-Ni-B 结构 磁性
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稀土配合物Sm_2(CH_3COO)_4(NO_3)_2(phen)_2的合成、结构及非等温热分解动力学研究 被引量:4
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作者 邢永恒 袁厚群 +5 位作者 张元红 张宝莉 徐芬 孙立贤 牛淑云 白凤英 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2006年第7期1205-1210,共6页
在水-乙醇混合体系中,将浓硝酸硝化的Sm2O3与1,10-邻菲啰啉反应,用冰醋酸调节pH≈4,形成醋酸根桥联的双核钐配合物[Sm2(CH3COO)4(NO3)2(phen)2](phen=1,10-邻菲啰啉),用元素分析、红外光谱和核磁共振谱等进行了表征,并用X射线衍射测定... 在水-乙醇混合体系中,将浓硝酸硝化的Sm2O3与1,10-邻菲啰啉反应,用冰醋酸调节pH≈4,形成醋酸根桥联的双核钐配合物[Sm2(CH3COO)4(NO3)2(phen)2](phen=1,10-邻菲啰啉),用元素分析、红外光谱和核磁共振谱等进行了表征,并用X射线衍射测定了配合物的晶体结构,此外,对配合物进行了非等温热分解动力学研究.该晶体属于三斜晶系,P1空间群,晶胞参数a=0.979 6(3)nm,b=0.981 3(4)nm,c=1.127 3(4)nm,α=106.666(5)°,β=113.034(5)°,γ=102.656(5),°V=0.885 4(5)nm3,Z=1,μ=3.361 mm-1,Dc=1.915 g/cm3,F(000)=498,R1=0.059 6,wR2=0.144 8.该配合物是双核分子,2个Sm(Ⅲ)离子通过4个醋酸根的羧基桥联,每个中心离子分别与周围5个来自羧基的桥氧原子、一个硝酸根的两个氧原子和一个邻菲啰啉分子中的两个氮原子配位,形成九配位扭曲多面体.非等温热分解动力学研究结果表明,配合物第一步热分解反应可能为二级反应,其动力学方程为dα/dT=A/[βe-E/RT(1-α)2],分解反应的表观活化能为344.84 kJ/mol,指前因子lnA=66.52. 展开更多
关键词 钐配合物 1 10-邻菲哕啉 晶体结构 热分解动力学
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基于SCBSS信号处理技术的SMS多参量光纤传感系统 被引量:4
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作者 李强 王智 +2 位作者 黄泽铗 郭凯丽 刘岚岚 《红外与激光工程》 EI CSCD 北大核心 2014年第10期3383-3387,共5页
基于单通道盲信号分离技术(Single Channel Blind Source Separation,SCBSS)及单模-多模-单模(Single-mode-Multimode-Single-mode,SMS)光纤结构的模间干涉理论,提出了一种多参量光纤传感技术,实现了振动与应力、振动与温度的同时测量... 基于单通道盲信号分离技术(Single Channel Blind Source Separation,SCBSS)及单模-多模-单模(Single-mode-Multimode-Single-mode,SMS)光纤结构的模间干涉理论,提出了一种多参量光纤传感技术,实现了振动与应力、振动与温度的同时测量。在振动与应力同时测量时,振动频率误差为0.17 Hz,分离出的应力信号与实验操作吻合。在振动与线性降温、自然升温同时测量实验中,振动频率误差均在0.60Hz以内。线性降温时,温度误差在7.13%以内;自然升温时,温度误差在8.03%以内。该方法结构简单,成本低廉,精度高,可推广用于其他光纤传感系统,实现多参量同时测量。 展开更多
关键词 光纤传感 单通道盲信号分离 多参量测量 smS光纤结构 模间干涉
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