Magnetic Properties of J-J-J' Quantum Heisenberg Chains with Spin S=12, 1, 32 and 2 in a Ma

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SQUID(超导量子干涉仪)

SQUID(超导量子干涉仪)
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Principles and applications of SQUID J.Clarke
SSM(扫描超导量子干涉显微镜)
Phys. Rev. Lett. 12, 159 - 160 (1964) R. C. Jaklevic et al.
• 60年代下半叶,制造简陋的dc SQUID开始为低温物理学家用于测量。 • 60年代末开始出现RF SQUID。 • 相当长的时间内,dc SQUID被摒弃,直到1974年出现灵敏性高于 RFSQUID的仪器。 • 1987年Koch和Nakane首先制造出了高温dc-SQUID。 Appl. Phys. Lett. 51(3). 20 July
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碳量子点的合成、性质及应用

碳量子点的合成、性质及应用

CHEMICAL INDUSTRY AND ENGINEERING PROGRESS 2017年第36卷第5期·1734·化 工 进展碳量子点的合成、性质及应用高雪1,2,孙靖1,2,刘晓1,2,王华1,2,韩金玉1,2(1天津大学化工学院,天津 300072;2绿色合成与转化教育部重点实验室,天津 300072)摘要:碳量子点的研究引起了国内外学者的广泛关注,近年来更是掀起了以天然物质为碳源制备碳量子点的研究热潮。

本文基于碳量子点的最新研究进展,总结了碳量子点不同的合成方法,主要包括电弧放电法、激光销蚀法、电化学合成法等“自上而下”合成法与燃烧法、水热法等“自下而上”合成法。

此外,还重点介绍了碳量子点的表征技术,如透射电子显微镜、拉曼光谱、荧光光谱、紫外可见光谱、X 射线衍射、核磁共振技术等,以及碳量子点的性质及其在生物成像、生物传感与检测和光催化等领域的应用。

最后展望了未来碳量子点在光催化、电催化等领域研究工作的发展方向。

关键词:碳量子点;合成方法;荧光;生物成像;光催化中图分类号:O613.71 文献标志码:A 文章编号:1000–6613(2017)05–1734–09 DOI :10.16085/j.issn.1000-6613.2017.05.023Carbon quantum dots: synthesis ,properties and applicationsGAO Xue 1,2,SUN Jing 1,2,LIU Xiao 1,2,WANG Hua 1,2,HAN Jinyu 1,2(1School of Chemical Engineering and Technology ,Tianjin University ,Tianjin 300072,China; 2Key Laboratory forGreen Chemical Technology of Ministry of Education ,Tianjin 300072,China )Abstract :As a kind of burgeoning carbon nanomaterials ,carbon quantum dots have attracted muchresearch attention in recent years ,especially those prepared by using natural substances as the origin of carbon. In this review ,various synthesis methods of carbon quantum dots were introduced based on the latest research progress ,including top-down approach and bottom-up approach. In addition ,we summarized the typical characterization methods for carbon dots ,such as TEM ,Raman spectrum ,fluorescence spectrum ,ultraviolet-visible spectrum ,X-ray diffraction ,and nuclear magnetic resonance. The properties of carbon quantum dots and their applications in bioimaging ,biological sensing and detection as well as photocatalysis are also introduced. Finally ,the future development of carbon quantum dots in photocatalysis and electrocatalysis are forecasted. Key words :carbon-quantum-dots ;synthetic approaches ;photoluminescene ;bioimaging ;photocatalysis碳元素是自然界中含量最丰富的元素之一,也是构成生命体最基本的元素。

磁学 径向克尔 英文 kerr effect

磁学 径向克尔 英文 kerr effect

IntroductionThe Kerr effect, also known as the magneto-optic Kerr effect (MOKE), is a phenomenon that manifests the interaction between light and magnetic fields in a material. It is named after its discoverer, John Kerr, who observed this effect in 1877. The radial Kerr effect, specifically, refers to the variation in polarization state of light upon reflection from a magnetized surface, where the change occurs radially with respect to the magnetization direction. This unique aspect of the Kerr effect has significant implications in various scientific disciplines, including condensed matter physics, materials science, and optoelectronics. This paper presents a comprehensive, multifaceted analysis of the radial Kerr effect, delving into its underlying principles, experimental techniques, applications, and ongoing research directions.I. Theoretical Foundations of the Radial Kerr EffectA. Basic PrinciplesThe radial Kerr effect arises due to the anisotropic nature of the refractive index of a ferromagnetic or ferrimagnetic material when subjected to an external magnetic field. When linearly polarized light impinges on such a magnetized surface, the reflected beam experiences a change in its polarization state, which is characterized by a rotation of the plane of polarization and/or a change in ellipticity. This alteration is radially dependent on the orientation of the magnetization vector relative to the incident light's plane of incidence. The radial Kerr effect is fundamentally governed by the Faraday-Kerr law, which describes the relationship between the change in polarization angle (ΔθK) and the applied magnetic field (H):ΔθK = nHKVwhere n is the sample's refractive index, H is the magnetic field strength, K is the Kerr constant, and V is the Verdet constant, which depends on the wavelength of the incident light and the magnetic properties of the material.B. Microscopic MechanismsAt the microscopic level, the radial Kerr effect can be attributed to twoprimary mechanisms: the spin-orbit interaction and the exchange interaction. The spin-orbit interaction arises from the coupling between the electron's spin and its orbital motion in the presence of an electric field gradient, leading to a magnetic-field-dependent modification of the electron density distribution and, consequently, the refractive index. The exchange interaction, on the other hand, influences the Kerr effect through its role in determining the magnetic structure and the alignment of magnetic moments within the material.C. Material DependenceThe magnitude and sign of the radial Kerr effect are highly dependent on the magnetic and optical properties of the material under investigation. Ferromagnetic and ferrimagnetic materials generally exhibit larger Kerr rotations due to their strong net magnetization. Additionally, the effect is sensitive to factors such as crystal structure, chemical composition, and doping levels, making it a valuable tool for studying the magnetic and electronic structure of complex materials.II. Experimental Techniques for Measuring the Radial Kerr EffectA. MOKE SetupA typical MOKE setup consists of a light source, polarizers, a magnetized sample, and a detector. In the case of radial Kerr measurements, the sample is usually magnetized along a radial direction, and the incident light is either p-polarized (electric field parallel to the plane of incidence) or s-polarized (electric field perpendicular to the plane of incidence). By monitoring the change in the polarization state of the reflected light as a function of the applied magnetic field, the radial Kerr effect can be quantified.B. Advanced MOKE TechniquesSeveral advanced MOKE techniques have been developed to enhance the sensitivity and specificity of radial Kerr effect measurements. These include polar MOKE, longitudinal MOKE, and polarizing neutron reflectometry, each tailored to probe different aspects of the magnetic structure and dynamics. Moreover, time-resolved MOKE setups enable the study of ultrafast magneticphenomena, such as spin dynamics and all-optical switching, by employing pulsed laser sources and high-speed detection systems.III. Applications of the Radial Kerr EffectA. Magnetic Domain Imaging and CharacterizationThe radial Kerr effect plays a crucial role in visualizing and analyzing magnetic domains in ferromagnetic and ferrimagnetic materials. By raster-scanning a focused laser beam over the sample surface while monitoring the Kerr signal, high-resolution maps of domain patterns, domain wall structures, and magnetic domain evolution can be obtained. This information is vital for understanding the fundamental mechanisms governing magnetic behavior and optimizing the performance of magnetic devices.B. Magnetometry and SensingDue to its sensitivity to both the magnitude and direction of the magnetic field, the radial Kerr effect finds applications in magnetometry and sensing technologies. MOKE-based sensors offer high spatial resolution, non-destructive testing capabilities, and compatibility with various sample geometries, making them suitable for applications ranging from magnetic storage media characterization to biomedical imaging.C. Spintronics and MagnonicsThe radial Kerr effect is instrumental in investigating spintronic and magnonic phenomena, where the manipulation and control of spin degrees of freedom in solids are exploited for novel device concepts. For instance, it can be used to study spin-wave propagation, spin-transfer torque effects, and all-optical magnetic switching, which are key elements in the development of spintronic memory, logic devices, and magnonic circuits.IV. Current Research Directions and Future PerspectivesA. Advanced Materials and NanostructuresOngoing research in the field focuses on exploring the radial Kerr effect in novel magnetic materials, such as multiferroics, topological magnets, and magnetic thin films and nanostructures. These studies aim to uncover newmagnetooptical phenomena, understand the interplay between magnetic, electric, and structural order parameters, and develop materials with tailored Kerr responses for next-generation optoelectronic and spintronic applications.B. Ultrafast Magnetism and Spin DynamicsThe advent of femtosecond laser technology has enabled researchers to investigate the radial Kerr effect on ultrafast timescales, revealing fascinating insights into the fundamental processes governing magnetic relaxation, spin precession, and all-optical manipulation of magnetic order. Future work in this area promises to deepen our understanding of ultrafast magnetism and pave the way for the development of ultrafast magnetic switches and memories.C. Quantum Information ProcessingRecent studies have demonstrated the potential of the radial Kerr effect in quantum information processing applications. For example, the manipulation of single spins in solid-state systems using the radial Kerr effect could lead to the realization of scalable, robust quantum bits (qubits) and quantum communication protocols. Further exploration in this direction may open up new avenues for quantum computing and cryptography.ConclusionThe radial Kerr effect, a manifestation of the intricate interplay between light and magnetism, offers a powerful and versatile platform for probing the magnetic properties and dynamics of materials. Its profound impact on various scientific disciplines, coupled with ongoing advancements in experimental techniques and materials engineering, underscores the continued importance of this phenomenon in shaping our understanding of magnetism and driving technological innovations in optoelectronics, spintronics, and quantum information processing. As research in these fields progresses, the radial Kerr effect will undoubtedly continue to serve as a cornerstone for unraveling the mysteries of magnetic materials and harnessing their potential for transformative technologies.。

(2021年整理)材料专业常用术语英语单词表

(2021年整理)材料专业常用术语英语单词表

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Unit 1property (材料的)性质heat treatment 热处理metal 金属glass 玻璃plastics 塑料fiber 纤维electronic devices 电子器件component 组元,组分semiconducting materials 半导体材料materials science and engineering 材料科学与工程materials science 材料科学materials engineering 材料工程materials scientist 材料科学家materials engineer 材料工程师synthesize 合成synthesissubatomic structure 亚原子结构electron 电子atom 原子nuclei 原子核nucleusmolecule 分子microscopic 微观的microscope 显微镜naked eye 裸眼macroscopic 宏观的specimen 试样deformation 变形polished 抛光的reflect 反射magnitude 量级solid materials 固体材料mechanical properties 力学性质force 力elastic modulus 弹性模量strength 强度electrical properties 电学性质electrical conductivity 导电性dielectric constant 介电常数electric field 电场thermal behavior 热学行为heat capacity 热容thermal conductivity 热传导(导热性)magnetic properties 磁学性质magnetic field 磁场optical properties 光学性质electromagnetic radiation 电磁辐射light radiation 光辐射index of refraction 折射率reflectivity 反射率deteriorative characteristics 劣化特性processing 加工performance 性能linear 线性的integrated circuit chip 集成电路芯片strength 强度ductility 延展性deterioration 恶化,劣化mechanical strength 机械强度elevated temperature 高温corrosive 腐蚀性的fabrication 制造Unit 2chemical makeup 化学组成atomic structure 原子结构advanced materials 先进材料high-technology 高技术smart materials 智能材料nanoengineered materials 纳米工程材料metallic materials 金属材料nonlocalized electrons 游离电子conductor 导体electricity 电heat 热transparent 透明的visible light 可见光polished 抛光的surface 表面lustrous 有光泽的aluminum 铝silicon 硅alumina 氧化铝silica 二氧化硅oxide 氧化物carbide 碳化物nitride 氮化物dioxide 二氧化物clay minerals 黏土矿物porcelain 瓷器cement 水泥mechanical behavior 力学行为ceramic materials 陶瓷材料stiffness 劲度strength 强度hard 坚硬brittle 脆的fracture 破裂insulative 绝缘的resistant 耐……的resistance 耐力,阻力,电阻molecular structures 分子结构chain-like 链状backbone 骨架carbon atoms 碳原子low densities 低密度mechanical characteristics 力学特性inert 隋性synthetic (人工)合成的fiberglass 玻璃纤维polymeric 聚合物的epoxy 环氧树脂polyester 聚酯纤维carbon fiber—reinforced polymer composite 碳纤维增强聚合物复合材料glass fiber-reinforced materials 玻璃纤维增强材料high-strength, low-density structural materials 高强度低密度结构材料solar cell 太阳能电池hydrogen fuel cell 氢燃料电池catalyst 催化剂nonrenewable resource 不可再生资源Unit 3periodic table (元素)周期表atomic structure 原子结构magnetic 磁学的optical 光学的microstructure 微观结构macrostructure 宏观结构positively charged nucleus 带正电的原子核atomic number 原子序数proton 质子atomic weight 原子量neutron 中子negatively charged electrons 带负电的电子shell 壳层magnesium 镁chemical bonds 化学键partially-filled electron shells 未满电子壳层bond 成键metallic bond 金属键nonmetal atoms 非金属原子covalent bond 共价键ionic bond 离子键Unit 4physical properties 物理性质chemical properties 化学性质flammability 易燃性corrosion 腐蚀oxidation 氧化oxidation resistance 抗氧化性vapor (vapour)蒸汽,蒸气,汽melt 熔化solidify 凝固vaporize 汽化,蒸发condense 凝聚sublime 升华state 态plasma 等离子体phase transformation temperatures 相变温度density 密度specific gravity 比重thermal conductivity 热导linear coefficient of thermal expansion 线性热膨胀系数electrical conductivity and resistivity 电导和电阻corrosion resistance 抗腐蚀性magnetic permeability 磁导率phase transformations 相变phase transitions 相变crystal forms 晶型melting point 熔点boiling point 沸腾点vapor pressure 蒸气压atm 大气压glass transition temperature 玻璃化转变温度mass 质量volume 体积per unit of volume 每单位体积the acceleration of gravity 重力加速度temperature dependent 随温度而变的,与温度有关的grams/cubic centimeter 克每立方厘米kilograms/cubic meter 千克每立方米grams/milliliter 克每毫升grams/liter 克每升pounds per cubic inch 磅每立方英寸pounds per cubic foot 磅每立方英尺alcohol 酒精benzene 苯magnetize 磁化magnetic induction 磁感应强度magnetic field intensity 磁场强度constant 常数vacuum 真空magnetic flux density 磁通密度diamagnetic 反磁性的factor 因数paramagnetic 顺磁性的ferromagnetic 铁磁性的non-ferrous metals 非铁金属,有色金属brass 黄铜ferrous 含铁的ferrous metals 含铁金属,黑色金属relative permeability 相对磁导率transformer 变压器,变换器eddy current probe 涡流探针Unit 5hardness 硬度impact resistance 耐冲击性fracture toughness 断裂韧度,断裂韧性structural materials 结构材料anisotropic 各向异性orientation 取向texture 织构fiber reinforcement 纤维增强longitudinal 纵向transverse direction 横向short transverse direction 短横向a function of temperature 温度的函数,温度条件room temperature 室温elongation 伸长率tension 张力,拉力compression 压缩bending 弯曲shear 剪切torsion 扭转static loading 静负荷dynamic loading 动态载荷cyclic loading 循环载荷,周期载荷cross-sectional area 横截面stress 应力stress distribution 应力分布strain 应变engineering strain 工程应变perpendicular 垂直normal axis 垂直轴elastic deformation 弹性形变plastic deformation 塑性形变quality control 质量控制nondestructive tests 无损检测tensile property 抗张性能,拉伸性能Unit 6lattice 晶格positive ions 正离子a cloud of delocalized electrons 离域电子云ionization 电离,离子化metalloid 准金属,类金属nonmetal 非金属diagonal line 对角线polonium 钋semi—metal 半金属lower left 左下方upper right 右上方conduction band 导带valence band 价带electronic structure 电子结构synthetic materials (人工)合成材料oxygen 氧oxide 氧化物rust 生锈potassium 钾alkali metals 碱金属alkaline earth metals 碱土金属volatile 活泼的transition metals 过渡金属oxidize 氧化barrier layer 阻挡层basic 碱性的acidic 酸性的electrochemical series 电化序electrochemical cell 电化电池cleave 解理,劈开elemental 元素的,单质的metallic form 金属形态tightly-packed crystal lattice 密排晶格,密堆积晶格atomic radius 原子半径nuclear charge 核电荷number of bonding orbitals 成键轨道数overlap of orbital energies 轨道能重叠crystal form 晶型planes of atoms 原子面a gas of nearly free electrons 近自由电子气free electron model 自由电子模型an electron gas 电子气band structure 能带结构binding energy 键能positive potential 正势periodic potential 周期性势能band gap 能隙Brillouin zone 布里渊区nearly-free electron model 近自由电子模型solid solution 固溶体pure metals 纯金属duralumin 硬铝,杜拉铝Unit 9purification 提纯,净化raw materials 原材料discrete 离散的,分散的iodine 碘long—chain 长链alkane 烷烃,链烃oxide 氧化物nitride 氮化物carbide 碳化物diamond 金刚石graphite 石墨inorganic 无机的mixed ionic—covalent bonding 离子-共价混合键constituent atoms 组成原子conduction mechanism 传导机制phonon 声子photon 光子sapphire 蓝宝石visible light 可见光computer-assisted process control 计算机辅助过程控制solid—oxide fuel cell 固体氧化物燃料电池spark plug insulator 火花塞绝缘材料capacitor 电容electrode 电极electrolyte 电解质electron microscope 电子显微镜surface analytical methods 表面分析方法Unit 12macromolecule 高分子repeating structural units 重复结构单元covalent bond 共价键polymer chemistry 高分子化学polymer physics 高分子物理polymer science 高分子科学molecular structure 分子结构molecular weights 分子量long chains 长链chain—like structure 链状结构monomer 单体plastics 塑料rubbers 橡胶thermoplastic 热塑性thermoset 热固性vulcanized rubbers 硫化橡胶thermoplastic elastomer 热塑弹性体natural rubbers 天然橡胶synthetic rubbers 合成橡胶thermoplastic 热塑性thermoset 热固性resin 树脂polyethylene 聚乙烯polypropylene 聚丙烯polystyrene 聚苯乙烯polyvinyl—chloride 聚氯乙烯polyvinyl 聚乙烯的chloride 氯化物polyester 聚酯polyurethane 聚氨酯polycarbonate 聚碳酸酯nylon 尼龙acrylics 丙烯酸树脂acrylonitrile-butadiene—styrene ABS树脂polymerization 聚合(作用)condensation polymerization 缩聚addition polymerization 加聚homopolymer 均聚物copolymer 共聚物chemical modification 化学改性terminology 术语nomenclature 命名法chemist 化学家the Noble Prize in Chemistry 诺贝尔化学奖catalyst 催化剂atomic force microscope 原子力显微镜(AFM) Unit 15composite 复合材料multiphase 多相bulk phase 体相matrix 基体matrix material 基质材料reinforcement 增强体reinforcing phase 增强相reinforcing material 加强材料metal—matrix composite 金属基复合材料ceramic—matrix composite 陶瓷基复合材料resin—matrix composite 树脂基复合材料strengthening mechanism 增强机理dispersion strengthened composite 弥散强化复合材料particle reinforced composites 颗粒增强复合材料fiber—reinforced composites 纤维增强复合材料Unit 18nanotechnology 纳米技术nanostructured materials 纳米结构材料nanometer 纳米nanoscale 纳米尺度nanoparticle 纳米颗粒nanotube 纳米管nanowire 纳米线nanorod 纳米棒nanoonion 纳米葱nanobulb 纳米泡fullerene 富勒烯size parameters 尺寸参数size effect 尺寸效应critical length 临界长度mesoscopic 介观的quantum mechanics 量子力学quantum effects 量子效应surface area per unit mass 单位质量的表面积surface physics and chemistry 表面物理化学substrate 衬底,基底graphene 石墨烯chemical analysis 化学分析chemical composition 化学成分analytical techniques 分析技术scanning tunneling microscope 扫描隧道显微镜spatial resolution 空间分辨率de Brogile wavelength 德布罗意波长mean free path of electrons (电子)平均自由程quantum dot 量子点band gap 带隙continuous density of states 连续态密度discrete energy level 离散能级absorption 吸收infrared 红外ultraviolet 紫外visible 可见quantum confinement (effect) 量子限域效应quantum well 量子势阱optoelectronic device 光电子器件energy spectrum 能谱electron mean free path 电子平均自由程spin relaxation length 自旋弛豫长度Unit 21biomaterial 生物材料implant materials 植入材料biocompatibility 生物相容性in vivo 在活体内in vitro 在活体外organ transplant 器管移植calcium phosphate 磷酸钙hydroxyapatite 羟基磷灰石research and development 研发 R&D Preparation & Characterizationprocessing techniques 加工技术casting 铸造rolling 轧制,压延welding 焊接ion implantation 离子注入thin—film deposition 薄膜沉积crystal growth 晶体生长sintering 烧结glassblowing 玻璃吹制analytical techniques 分析技术characterization techniques 表征技术electron microscopy 电子显微术X—ray diffraction X射线衍射calorimetry 量热法Rutherford backscattering 卢瑟福背散射neutron diffraction 中子衍射nuclear microscopy 核子微探针。

原子物理轨道知识

原子物理轨道知识

原子轨道原子轨道(Atomic orbital)是单电子薛定谔方程的合理解ψ(x,y,z)。

若用球坐标来描述这组解,即ψ(r,θ,φ)=R(r)·Y(θ,φ),这里R(r)是与径向分布有关的函数,称为径向分布函数,用图形描述就是原子轨道的径向分布函数;Y(θ,φ)是与角度分布有关的函数,用图形描述就是角度分布函数。

1简介原子轨道(英语:atomic orbital),又称轨态,是以数学函数描述原子中电子似波行为[1][2]。

此波函数可用来计算在原子核外的特定空间中,找到原子中电子的机率,并指出电子在三维空间中的可能位置[1][3]。

“轨道”便是指在波函数界定下,电子在原子核外空间出现机率较大的区域。

具体而言,原子轨道是在环绕着一个原子的许多电子(电子云)中,个别电子可能的量子态,并以轨道波函数描述。

电子的原子与分子轨道,依照能阶排序现今普遍公认的原子结构是波耳氢原子模型:电子像行星,绕着原子核(太阳)运行。

然而,电子不能被视为形状固定的固体粒子,原子轨道也不像行星的椭圆形轨道。

更精确的比喻应是,大范围且形状特殊的“大气”(电子),分布于极小的星球(原子核)四周。

只有原子中存在唯一电子时,原子轨道才能精准符合“大气”的形状。

当原子中有越来越多电子时,电子越倾向均匀分布在原子核四周的空间体积中,因此“电子云”[4]越倾向分布在特定球形区域内(区域内电子出现机率较高)。

早在1904年,日本物理学家长冈半太郎首度发表电子以类似环绕轨道的方式在原子内运转的想法[5]。

1913年,丹麦物理学家尼尔斯·波耳提出理论,主张电子以固定的角动量环绕着体积极小的原子核运行[6]。

然而,一直到1926年、量子力学发展后,薛定谔方程式才解释了原子中的电子波动,定下关于新概念“轨道”的函数[1][7]。

由于这个新概念不同于古典物理学中的轨道想法,1932年美国化学家罗伯特·马利肯提出以“轨道”(orbital)取代“轨道”(orbit)一词[8]。

几何阻挫磁体简介000

几何阻挫磁体简介000

PM
阻挫磁体的判据: f
CW
TF
5
S0 / kB lnW
特征:基态存在很大的简并度 传统反铁磁体:
f
CW
TF
~1
Square Lattice:
Td ~ 2CW Td ~ 0.75CW
Triangular Lattice:
•多重简并基态
Triangular Lattice
三角晶格:6重简并 2重简并(FM) Kagome Lattice
→AFM+Spin
Liquid
→AFM
例2:ZnCr2O4
AFM → Quasispin Glass
问题1:几何阻挫磁体是否存在亚铁磁体?
First experimental realization of spin Ladder with FM Legs
问题2:几何阻挫自旋玻璃与传统自旋玻璃区别?
PRL,106, 247202 (2011
1.ACr2O4 (A=Zn,Cd,Hg) 几何阻挫磁体(Tetragonal Lattice)
•Cr3+ 占据四面体顶角
•Cr3+ 自旋占据t2g轨道, 只有自旋—晶格耦合
Cd
Cr
c
b
a
•强磁场诱导磁相变
强磁场调制“自旋—晶格”耦合
Orthorhombic(Fddd)
量子临界行为
磁场诱导量子相变
?
?
Magnetic Field-induced quantum phase transition: 概念:Noncollinear spin structure ———— Collinear spin Structure (First Order Transition) Example: Pyrochlore Lttice

磁通门 磁环 纳米晶

磁通门 磁环 纳米晶

磁通门磁环纳米晶英文回答:Fluxgate magnetometer.A fluxgate magnetometer is a type of magnetometer that uses a magnetic core to measure the magnetic field. The magnetic core is made of a high-permeability material, such as iron or nickel, and is wound with a coil of wire. When the coil is energized, the magnetic core becomes magnetized and the magnetic field is concentrated in the core. The magnetic field of the core is then measured by a secondcoil of wire, which is wound around the core.Fluxgate magnetometers are used in a variety of applications, including:Geophysical exploration.Underwater navigation.Metal detection.Medical imaging.Fluxgate magnetometers are relatively inexpensive and easy to use, and they can be used to measure magneticfields over a wide range of frequencies. However, fluxgate magnetometers are not as sensitive as other types of magnetometers, such as superconducting quantum interference devices (SQUIDs).Magnetic ring.A magnetic ring is a type of magnetic material that has a hole in the center. Magnetic rings are often used in electronic circuits to store energy or to filter out unwanted frequencies. Magnetic rings are also used in some types of transformers.Magnetic rings are made of a variety of materials, including:Iron.Nickel.Cobalt.Ferrites.The magnetic properties of a magnetic ring depend on the material used to make the ring. Iron rings have the highest magnetic permeability, but they are also the most susceptible to saturation. Nickel rings have a lower magnetic permeability than iron rings, but they are more resistant to saturation. Cobalt rings have the highest magnetic saturation flux density, but they are also the most expensive. Ferrite rings have a lower magnetic permeability than iron or nickel rings, but they are also more resistant to saturation.Nanocrystalline.Nanocrystalline materials are materials that have a grain size of less than 100 nanometers. Nanocrystalline materials have unique magnetic properties that make them ideal for use in a variety of applications, including:Magnetic recording.Magnetic sensors.Magnetic actuators.Nanocrystalline materials are made by a variety of methods, including:Rapid solidification.Mechanical alloying.Chemical vapor deposition.The magnetic properties of a nanocrystalline material depend on the grain size and the composition of thematerial. Nanocrystalline materials with smaller grainsizes have higher magnetic permeability and lower coercivity. Nanocrystalline materials with a higher concentration of magnetic elements have higher magnetic saturation flux density.中文回答:磁通门磁力计。

凝聚态物理英语

凝聚态物理英语

凝聚态物理英语Condensed matter physics is a branch of physics that deals with the macroscopic and microscopic properties of matter, specifically the behavior of solids and liquids. It is a highly interdisciplinary field that explores the quantum mechanical properties of matter in bulk. This field of study has led to numerous technological advancements and has greatly impacted our understanding of the physical world.One of the key concepts in condensed matter physics is the study of phase transitions. Phase transitions occur when a material changes from one state to another, such as from a solid to a liquid or from a liquid to a gas. These transitions are characterized by changes in the material's physical properties, such as density, conductivity, and magnetization. Understanding the mechanisms behind phase transitions is essential for developing new materials with novel properties and applications.Another important area of research in condensed matter physics is the study of quantum phenomena in solids. Quantum mechanics describes the behavior of particles on the atomic and subatomic levels, and in condensed matter physics, these principles are applied to understand the interactions between atoms in solids. Quantum phenomena in solids can lead tounique properties such as superconductivity, where materials exhibit zero resistance to electrical current, and magnetism, where materials exhibit magnetic properties due to the alignment of electron spins.Condensed matter physics also plays a crucial role in the development of new materials for various technologies. Researchers in this field work to understand the properties of materials at the atomic level and how they can be manipulated to create materials with specific properties. This knowledge has led to the development of new materials for applications in electronics, energy storage, and medical devices.In recent years, there has been a growing interest in the study of topological materials in condensed matter physics. Topological materials are materials that exhibit unique electronic properties due to their topological structure, which is determined by the arrangement of atoms in the material. These materials have the potential to revolutionize electronics and computing by enabling the development of new types of electronic devices with improved performance and efficiency.Overall, condensed matter physics is a diverse and dynamic field of study that continues to push the boundaries of our understanding of the physical world. Through the study of phasetransitions, quantum phenomena, and novel materials, researchers in this field are continually expanding our knowledge of matter and developing new technologies that have the potential to transform society.In conclusion, condensed matter physics is a fascinating and important field of study that has a profound impact on our understanding of the physical world and on technological advancements. Researchers in this field continue to make significant contributions to science and technology, and the future of condensed matter physics holds great promise for exciting new discoveries and innovations.。

张利强 - 中国石油大学

张利强 - 中国石油大学

张利强中国石油大学(北京),理学院材料科学与工程系,助理研究员张利强,男,助理研究员。

2012年6月入选中国石油大学(北京)青年拔尖人才,并于2012年7月入职中国石油大学(北京)。

在2009年底,申请人得到国家留学基金委全额资助到美国进行为期两年的联合培养,师从世界著名材料学家匹兹堡大学Scott X Mao教授与美国桑迪亚国家实验室黄建宇研究员。

研究课题为新型能源材料的设计与改性。

在美国桑迪亚国家实验室期间,在黄建宇研究员的指导下使用透射电镜在2010年底合作制备出迄今为止世界上最小的电池,其成果发表在世界顶级杂志《Science》上,受到世界同行的关注,并被美国多家电视台报道,并被百度、新浪等门户网站评选为2010年世界七大科技之最之一。

近三年来,申请人在Science(IF=31.201),Nano.Lett.(IF=13.19),ACS nano(IF=10.77)等杂志,以合作作者和第一作者共发表论文23篇,他引200余次,累计影响因子111,并申请8项发明专利。

受教育经历(从大学本科开始,按时间倒排序)2010/01 – 2011/12,美国Sandia国家实验室,联合培养2009/12 – 2011/12,美国匹兹堡大学,材料系,联合培养2007/09 – 2012/06,浙江大学,材料系,博士2003/09 – 2007/06,东北大学,理学院材料物理系,学士研究工作经历(按时间倒排序)2012/07 – 至今,中国石油大学(北京),理学院材料系,助理研究员主要论著(近3年来已发表的与本项目有关的主要论著目录和获得学术奖励情况)1、期刊论文:[1]L.Q. Zhang, Z.Z. Ye, B. Lu, J.G. Lu, J.Y. Huang, Y.Z. Zhang, and Z Xie, Defect-inducedferromagnetism in insulating Mn–P codoped ZnO grown in oxygen-rich environment Thin Solid Films, 155 (2013) 16.[2]L.Q. Zhang, B. Lu, Y. H. Lu, Z. Z. Ye, J. G. Lu, X. H. Pan, and J. Y. Huang, Non-polarp-type Zn0.94Mn0.05Na0.01O texture: growth mechanism and codoping effect, J. Appl. Phys., 113 (2013) 083513.[3]L.Q. Zhang, X.H. Liu, Y.-C. Perng, J. Cho, J.P. Chang, S.X. Mao, Z.Z. Ye, and J.Y. Huang,Direct observation of Sn crystal growth during the lithiation and delithiation processes of SnO2 nanowires,Micron, 43 (2012) 1127.[4]L.Q. Zhang, Y.Z. Zhang, Z.Z. Ye, J.G. Lu, B. Lu, B. He, The effects of group-I elementsco-doping with Mn in ZnO dilute magnetic semiconductor, J. Appl. Phys.,111 (2012) 123524.[5]L.Q. Zhang, X.H. Liu, Y. Liu, S. Huang, T. Zhu, L.J. Gui, S.X. Mao, Z.Z. Ye, C. M. Wang, J.P. Sullivan, J.Y. Huang, Controlling the Lithiation-Induced Strain and Charging Rate in Nanowire Electrodes by Coating, ACS Nano, 5 (2011) 4800-4809.[6]L.Q. Zhang, Z.Z. Ye, J.Y. Huang, B. Lu, H.P. He, J.G. Lu, Y.Z. Zhang, J. Jiang, J. Zhang,K.W. Wu, W.G. Zhang, Fabrication and properties of p-type K doped Zn1-x Mg x O thin film, J.Alloys Compd.,509 (2011) 7405-7409.[7]L.Q. Zhang, Z.Z. Ye, B. Lu, J.G. Lu, Y.Z. Zhang, L.P. Zhu, J.Y. Huang, W.G. Zhang, J.Huang, J. Zhang, J. Jiang, K.W. Wu, Z. Xie, Ferromagnetism induced by donor-related defects in Co-doped ZnO thin films, J. Alloys Compd.,509 (2011) 2149-2153[8]L.Q. Zhang, Z.Z. Ye, B. Lu, J.G. Lu, Y.Z. Zhang, L.P. Zhu, J. Zhang, J. Jiang, K.W. Wu, B.He, Fabrication and properties of Li-doped ZnCoO diluted magnetic semiconductor thin films. Superlattices Microstruct.,50 (2011) 261-268[9]L.Q. Zhang, Z.Z. Ye, S.S. Lin, Y.Z. Zhang, B. Lu, H. P. He, L. X. Chen, J. G. Lu, J. Jiang,K.W. Wu, J.Y. Huang, L. P. Zhu, The fabrication of Na doped p-type Zn1−x Mg x O films by pulsed laser deposition, Appl. Phys. A, 106 (2011) 191-196[10]L.Q. Zhang, Z.Z. Ye, J.G. Lu, B. Lu, Y.Z. Zhang, L.P. Zhu, J. Zhang, D. Yang, K.W. Wu, J.Huang, Z. Xie, Influence of p-type and n-type dopants on the magnetic properties of ZnCuO based diluted magnetic semiconductor thin films,J. Phys. D: Appl. Phys.,43 (2010) 015001.[11]H.W. Huang, L.Q. Zhang, W.K. Wu, Q. Yu, R. Chen, H.S. Yang, X.S. Peng, Z.Z. Ye,Hetero-metal cation control of CuO nanostructures and their high catalytic performance for CO oxidation Nanoscale, 24 (2012) 7832-7841[12]Lu B, L.Q. Zhang, Y.H. Lu, Z.Z. Ye, J.G. Lu, X.H. Pan, J.Y. Huang, Ferromagneticenhancement and magnetic anisotropy in nonpolar-oriented (Mn, Na)-codoped ZnO thin films. Appl. Phys. Lett.,101 (2012) 083513.[13]X.H. Liu, L.Q. Zhang, L. Zhong, Y. Liu, H. Zheng, J.W. Wang, J.-H. Cho, S.A. Dayeh, S.T.Picraux, J.P. Sullivan, S.X. Mao, Z.Z. Ye, J.Y. Huang, Ultrafast Electrochemical Lithiation of Individual Si Nanowire Anodes,Nano Lett., 11 (2011) 2251-2258[14]X.H. Liu, L. Zhong, L.Q. Zhang, A. Kushima, S. X. Mao, J. Li, Z.Z.Ye, J.P. Sullivan, J.Y.Huang, Lithium fiber growth on the anode in a nanowire lithium ion battery during charging, Appl. Phys. Lett., 98 (2011) 183107[15]X.T. Wang, L.P. Zhu, L.Q. Zhang, J. Jiang, Z.G. Yang, Z.Z. Ye, B. He, Properties of Nidoped and Ni–Ga co-doped ZnO thin films prepared by pulsed laser deposition J. Alloys Compd.,509 (2011) 3282 -3285.[16]W.G. Zhang, Bin Lu, L.Q. Zhang, J.G. Lu, M. Fang, K.W. Wu, B.H. Zhao, Z.Z. Ye, Influenceof preparation condition and doping concentration of Fe-doped ZnO thin films: Oxygen-vacancy related room temperature ferromagnetism, Thin Solid Films, 519 (2011) 6624-6628.[17]H.W. Huang, Q. Yu, Y.H. Ye, P. Wang, L.Q. Zhang, M.X. Gao, X.S. Peng, Z.Z. Ye, Thincopper oxide nanowires/carbon nanotubes interpenetrating networks for lithium ion batteries Crystengcomm, 14:21(2012) 7294-7300[18]J.Y. Huang, L. Zhong, C.M. Wang, J.P. Sullivan, W. Xu, L.Q. Zhang, S.X. Mao, N.S. Hudak,X.H. Liu, A. Subramanian, H.Y. Fan, L. Qi, A. Kushima, J. Li,In Situ Observation of theElectrochemical Lithiation of a Single SnO2Nanowire Electrode,Science, 330 (2010) 1515-1520[19]X.H. Liu, H. Zheng, L. Zhong, S. Huang, K. Karki, L.Q. Zhang, Y. Liu, A. Kushima, W.T.Liang, J.W. Wang, J.-H. Cho, E. Epstein, S.A. Dayeh, S.T. Picraux, T. Zhu, J. Li, J.P. Sullivan, J. Cumings, C. Wang, S.X. Mao, Z.Z. Ye, S. Zhang, J.Y. Huang, Anisotropic Swelling and Fracture of Silicon Nanowires during Lithiation, Nano Lett.,11 (2011) 3312-3318.[20]W.G. Zhang, Bin Lu, L.Q. Zhang, Y.H. Ye, and Z.Z. Ye, Growth Orientation and Propertiesof ZnCoO Thin Films,J. Mater. Sci. Eng.,29 (2011) 679-683.[21]H.P. He, S.S. Lin, G.D. Yuan, L.Q. Zhang, W.F. Zhang, L.B. Luo, Y.L. Cao, Zhizhen Ye, andS.-T. Lee, Single-Crystalline Sodium-Doped p-Type ZnO and ZnMgO Nanowires via Combination of Thin-Film and Nano Techniques, J. Phys. Chem. C, 115 (2011) 19018-19022.[22]J. Jiang, X.T. Wang, L.P. Zhu, L.Q. Zhang, Z.G. Yang, and Z.Z. Ye,Electrical and magneticproperties of ZnNiO thin films deposited by pulse laser deposition.J. Zhejiang Uni-Sci A (Appl Phys & Eng),12 (2011) 561-566.[23]J. Jiang, L.P. Zhu, H.P. He, Y. Li, Y.M. Guo, L. Cao, Y.G. Li, K.W. Wu, L.Q. Zhang, and Z.Z.Ye, Structural and optical properties of ZnCdO/ZnO multiple quantum wells grown on sapphire substrates using pulsed laser deposition, J. Appl. Phys.,112 (2012) 083513.2、会议论文:[1]L.Q. Zhang, X.H. Liu, Y. Liu, S. Huang, T. Zhu, L.J. Gui, S. X. Mao, Z. Z. Ye, C. M. Wang, J. P. Sullivan, J. Y. Huang, Controlling the Lithiation Induced Strain and Charging Rate in Nanowire Electrodes by Coating,2012 TMS symposium on Mechanical Behavior at Nanoscale. Orlando, FL, USA. 2012.03.15. Poster.3、专著:[1] 叶志镇,吕建国,张银珠,何海平,马全宝,张利强等,《氧化锌掺杂与制备方法》第六章ZnO基稀磁半导体, 浙江大学出版社, 25.7万字, 20094、专利:[1]叶志镇,张利强,张银珠,吕建国,何海平,朱丽萍,Co-Ga共掺的ZnO基稀磁半导体薄膜及其制备方法, 中国, 申请号: 200910095453.6[2]叶志镇,张利强,黄靖云,张银珠,朱丽萍,汪雷,蒋杰,薛雅,张俊,一种Mg-Na共掺的ZnO基发光二极管及其制备方法, 中国, 申请号: 200910100826.4[3]叶志镇,张利强,黄靖云,张银珠,一种垂直结构ZnO基多量子阱发光二极管及其制备方法, 中国, 申请号: 200910100985.4[4]叶志镇,张利强,蒋杰,黄靖云,张银珠,张维广,张俊,朱丽萍,一种Mg-K共掺的ZnO基发光二极管及其制备方法, 中国, 申请号: 201010220372.7[5]叶志镇,张利强,吕建国,何海平,朱丽萍,张银珠,一种非极性ZnO晶体薄膜的生长方法, 授权时间: 2010.8.25, 中国, 授权号: ZL200810164207.7[6]崔立山,张利强,邵阳,姜大强,杨峰,杜敏疏,郭云鹏,郭方敏,一种应用形状记忆合金赋予薄膜大弹性应变的方法, 中国, 申请号: 201310001136.X[7]张利强,崔立山,邵阳,姜大强,杨峰,杜敏疏,郭云鹏,郭方敏,利用形状记忆合金表面浮凸实现薄膜拉伸弹性应变的方法, 中国, 申请号: 201310000764.6[8]张利强,崔立山,张俊松,姜大强,邵阳,郭云鹏,一种形状记忆合金复合材料制成的锂离子电池及制备方法, 中国, 申请号: 201210448229.2。

磁感应强度基准技术评述

磁感应强度基准技术评述

磁感应强度基准技术评述伏吉庆;张伟;贺青【摘要】从不确定度和应用情况等方面介绍了当前磁感应强度量值单位的几类基准,包括基于计算线圈的实物基准、基于核磁共振原理的量子基准和基于质子旋磁比的基本物理常数基准.量子精密测量领域近年来发展迅速,出现了比传统核磁共振基准的准确度更高的原子磁共振量子基准、可以进一步拓展核磁共振基准的量值下限的超导-核磁共振技术等新进展.重点评述了现有的磁感应强度的量子基准,并介绍了一些有望进一步拓展磁学计量前沿的新进展.【期刊名称】《计量学报》【年(卷),期】2019(040)004【总页数】4页(P700-703)【关键词】计量学;磁感应强度基准;量子基准;核磁共振;原子磁共振【作者】伏吉庆;张伟;贺青【作者单位】中国计量科学研究院电磁计量科学研究所,北京100029;中国计量科学研究院电磁计量科学研究所,北京100029;中国计量科学研究院电磁计量科学研究所,北京100029【正文语种】中文【中图分类】TB9721 引言磁感应强度即磁通量密度(magnetic flux density, MFD)基准是为了定义、复现和传递MFD量值而建立的装置。

MFD基准装置经过了实物基准、量子基准和基本物理常数基准3个阶段的发展。

本文通过对比目前世界上有代表性的多个计量机构建立的基准装置,对相关技术进行综合评述。

2 基准技术简介2.1 实物基准磁场作为电场的一种相对论效应,无论从物理实质还是量值复现的角度,都可以从电学量导出。

早期的MFD基准一般是以石英或陶瓷作为骨架绕制的螺线管线圈实物基准。

通过精密测量线圈的电流值和线圈的几何量,利用Biot-Savart定律计算产生的MFD,即:(1)作为基准量值。

这种实物基准又叫计算线圈。

在最佳状态下,其相对不确定度ur可以达到(0.02~0.05)×10-6,受限于对几何量的测量误差[1,2]。

在目前的MFD基准中,计算线圈的极限准确度是最高的。

结构化学 英语

结构化学 英语

结构化学英语Structured ChemistryChemistry is a vast and complex field of study that encompasses the understanding of the composition, structure, and properties of matter. One of the key aspects of chemistry is the concept of structure, which plays a crucial role in determining the behavior and characteristics of chemical substances. Structural chemistry, a subfield of chemistry, focuses on the spatial arrangement of atoms and molecules, and how this arrangement influences the chemical and physical properties of materials.The study of structure in chemistry involves the investigation of the three-dimensional (3D) arrangements of atoms within molecules and the intermolecular interactions that exist between them. This knowledge is essential for understanding the behavior of chemical systems, predicting their properties, and designing new materials with desired characteristics.One of the fundamental tools used in structural chemistry is X-ray crystallography. This technique involves the bombardment of a crystalline sample with X-rays, which interact with the electrons inthe atoms of the crystal. The resulting diffraction pattern can be analyzed to determine the precise arrangement of atoms within the crystal structure. This information is crucial for understanding the properties of solid-state materials, such as metals, minerals, and ceramics.Another important technique in structural chemistry is nuclear magnetic resonance (NMR) spectroscopy. This method utilizes the magnetic properties of atomic nuclei to provide information about the chemical environment and connectivity of atoms within a molecule. NMR spectroscopy is widely used in the identification and characterization of organic compounds, as well as in the study of biomolecules, such as proteins and nucleic acids.In addition to these experimental techniques, computational methods have also become increasingly important in the field of structural chemistry. Quantum mechanical calculations, such as density functional theory (DFT), allow researchers to model the behavior of atoms and molecules at the quantum level, providing insights into their electronic structure and chemical reactivity.One of the key applications of structural chemistry is in the design and development of new materials. By understanding the relationship between the structure of a material and its properties, chemists can engineer substances with specific characteristics, suchas high strength, enhanced thermal stability, or improved electrical conductivity. This knowledge is particularly valuable in fields like materials science, nanotechnology, and catalysis.Another important aspect of structural chemistry is its role in the study of biological systems. The structures of proteins, nucleic acids, and other biomolecules are crucial for understanding their functions and interactions within living organisms. This knowledge is essential for the development of new drugs and the understanding of disease processes.In conclusion, the field of structural chemistry is a fundamental and multifaceted discipline that underpins our understanding of the physical and chemical properties of matter. Through the use of advanced experimental and computational techniques, structural chemists continue to unravel the mysteries of the molecular world, paving the way for new discoveries and innovations that have the potential to transform our lives.。

磁性材料

磁性材料

Wedged thin films present a range of thicknesses for study in a single sample. Decorated steps and quantum corrals have been grown with atomic-level control. Laterally patterned structures in the bottom include thin films, magnetic dots and wires, and arrays of magnetic-multilayer columns. The broad range of materials that can be grown in these nanostructures present many interesting fundamental questions and potential technological applications. They also present many experimental challenges, such as distinguishing magnetism in buried ultrathin layers from that at the interfaces between them. [Figure courtesy of S. D. Bader, Argonne National Laboratory.]
Figure Advanced computer disks consist of granular magnetic materials like CoPtCr with admixtures of boron or tantalum in order to minimize the transition width between the magnetic domains.

天津大学光学考研复习辅导资料及导师分数线信息

天津大学光学考研复习辅导资料及导师分数线信息

天津大学光学考研复习辅导资料及导师分数线信息 天津大学光学考研科目包括政治、外语以及普通物理、量子力学。

研究方向主要包括生物医学光子学;现代光学测试学与图像处理;量子光学与量子通讯;导波光学与集成光子学;衍射光学及其应用。

考生可根据自己的兴趣选择具体的研究方向。

专业代码、名称及研究方向考试科目备注复试科目:光学070300光学①101思想政治理论②201英语一③717普通物理④837量子力学天津大学光学近两年考研录取情况院(系、所)专业报考人数录取人数理学院(2012年)光学10 3理学院(2013年)光学11 6天津大学理学院光学2012年的报考人数为10人,录取人数为3人,2013年的报考人数为11人,录取人数为6人。

由真题可以发现,现在考点涉及的广度和深度不断扩宽和加深。

由天津考研网签约的天津大学在读本硕博团队搜集整理了天津大学理学院光学考研全套复习资料,帮助考生梳理知识点并构建知识框架。

真题解析部分将真题按照知识点划分,条理清晰的呈现在同学们眼前。

然后根据各个考点的近几年真题解析,让同学对热点、难点了然于胸。

只有做到了对真题规律和趋势的把握,8—10月底的提高复习才能有的放矢、事半功倍!天津大学理学院光学考研导师信息吴萍纵向课题经费课题名称Sn-Zn基和Sn-Cu-Bi无铅焊球凸点互连电迁移行为及其失效机理研究2011-01-01--2013-12-31 负责人:吴萍科技计划:国家自然科学基金拨款单位:国家基金委合同经费:37课题名称纳米结构无铅焊球的制备及其在电子封装技术中的应用2006-04-01--2009-12-31 负责人:吴萍科技计划:天津市自然科学基金重点项目拨款单位:天津市科委合同经费:20课题名称均匀颗粒成型法制备Sn-3.0Ag-0.5Cu、Sn-8Zn-3Bi无铅焊球的热力学机理研究2007-01-01--2009-12-31 负责人:吴萍科技计划:国家自然科学基金拨款单位:国家基金委合同经费:29课题名称新型无铅复合焊球的研制及其电迁移失效机理研究2011-04-01--2014-03-31 负责人:吴萍科技计划:天津市自然科学基金重点项目拨款单位:天津市科委合同经费:20期刊、会议论文吴萍、周伟、刘立娟、李宝凌、张洪波均匀液滴喷射三维快速成型方法与装置吴萍、周伟、刘立娟、李宝凌、张洪波均匀液滴喷射三维快速成型方法与装置吴萍、周伟、刘立娟、李宝凌、王艺自动焊球封装植球方法与装置吴萍、周伟、刘立娟、李宝凌、徐志伟一种二次库仑分裂制备纳米颗粒的装置米文博人才称号教育部新世纪人才、天津市131人才计划第一层次、天津大学北洋青年学者纵向课题经费课题名称反应溅射Fe4N薄膜的自旋极化率、自旋注入和磁电阻效应研究2012-01-01--2015-12-31 负责人:米文博科技计划:国家自然科学基金面上项目拨款单位:国家自然科学基金委员会合同经费:60课题名称粒度可控、取向生长的L10结构FePt-C基二维颗粒膜的微结构和磁性2008-01-01--2010-12-31 负责人:米文博科技计划:国家自然科学基金青年基金拨款单位:国家自然科学基金委员会合同经费:24课题名称有序化L10结构FePt-C基颗粒膜的制备、结构与磁性2008-04-01--2011-03-31 负责人:米文博科技计划:天津市自然科学基金面上项目拨款单位:天津市科委合同经费:10课题名称Fe4N/半导体异质结构的自旋相关电子输运特性2013-01-01--2015-12-31 负责人:米文博科技计划:教育部留学回国人员启动基金项目拨款单位:教育部合同经费:3课题名称反应溅射Fe4N薄膜的自旋相关电子输运特性研究2012-04-01--2015-03-31 负责人:米文博科技计划:天津市自然科学基金重点项目拨款单位:天津市科委合同经费:20课题名称柔性有机自旋阀的磁电阻效应研究2014-01-01--2016-12-31 负责人:米文博科技计划:教育部新世纪人才计划拨款单位:教育部合同经费:50 课题名称磁性金属—氧化物半导体复合薄膜的磁电阻效应研究2008-01-01--2010-12-31 负责人:米文博科技计划:教育部博士点基金新教师基金拨款单位:教育部合同经费:3.6期刊、会议论文李滋润、米文博、王晓姹、张西祥Interfacial Exchange Coupling Induced Anomalous Anisotropic Magnetoresistance in Epitaxial γ′-Fe4N/CoN Bilayers ACS Appl. Mater.& Interfacesnull李滋润、封秀平、王晓姹、米文博Anisotropic Magnetoresistance in Facing-Target Reactively Sputtered Epitaxial γ'-Fe4N Films Mater. Res. Bull.null王俊宝、米文博、王来森、彭栋梁Interfacial scattering induced enhancement of anomalous Hall effect in uniform Fe nanocluster assembled films Europhys. Lett.null 李滋润、米文博、王晓姹、白海力Inversion of Exchange Bias and Complex Magnetization Reversal in Full-Nitride Epitaxial γ′-Fe4N/CoN Bilayers J. Magn. Magn. Mater.null 冯楠、米文博、王晓姹、白海力First-Principles Study on The Interfacial Magnetic and Electronic Properties of Fe4N(001)/Si and Fe4N(111)/Graphene Bilayers Comput. Mater. Sci.null冯楠、米文博、王晓姹、白海力The Magnetism of Fe4N/Oxides (MgO, BaTiO3, BiFeO3) Interfaces From First-Principles Calculations RSC Advancesnull张雪静、米文博、王晓姹、白海力First-Principles Prediction of Electronic Structure and Magnetic Ordering of Rare-earth Metals Doped ZnO J. Alloys Compd.null王俊宝、米文博、王来森、彭栋梁Enhanced anomalous Hall effect in Fe nanocluster assembled thin films Phys. Chem. Chem. Phys.null冯楠、米文博、程迎春、郭载兵、Udo Schwingenschl?gl、白海力Magnetism by Interfacial Hybridization and p-type Doping of MoS2 in Fe4N/MoS2 Superlattices: A First Principles Study ACS Appl. Mater. & Interfaces null张雪静、米文博、王晓姹、程迎春、Udo Schwingenschl?gl The Interface between Gd andMonolayer MoS2: A First-Principles Study Scientific Reportsnull冯楠、米文博、程迎春、郭载兵、Udo Schwingenschl?gl、白海力First Principles Prediction of the Magnetic Properties of Fe-X6 (X=S, C, N, O, F) Doped Monolayer MoS2 Scientific Reportsnull张雪静、米文博、郭载兵、程迎春、陈贵峰、白海力Role of Anion Doping on Electronic Structure and Magnetism of GdN by First Principles Calculations RSC Advancesnull 米文博、郭载兵、段秀峰、张雪静、白海力Large Negative Magnetoresistance in Reactive Sputtered Polycrystalline GdNx Films Appl. Phys. Lett. null米文博、杨华、程迎春、陈贵峰、白海力Magnetic and Electronic Properties ofFe3O4/Graphene Heterostructures: First Principles Perspective J. Appl. Phys.null段秀峰、米文博、郭载兵、白海力Magnetoresistance and Anomalous Hall Effect of Reactive Sputtered Polycrystalline Ti1?xCrxN Films Thin Solid Filmsnull米文博、郭载兵、封秀平、白海力Reactively Sputtered Epitaxial γ'-Fe4N Films: Surface Morphology, Microstructure, Magnetic and Electrical Transport Propertie Acta Materialianull段秀峰、米文博、郭载兵、白海力 A Comparative Study of Transport Properties in Polycrystalline and Epitaxial Chromium Nitride Films J. Appl. Phys.null杨华、程迎春、陈贵峰、米文博、白海力Magnetic and Electronic Properties of Cu1-xFexO from First Principles Calculations RSC Advancesnull米文博、郭载兵、王清晓、杨洋、白海力Charge Ordering in Reactive Sputtered (100) and(111) Oriented Epitaxial Fe3O4 Films Scripta Materialianull杨华、金朝、米文博、白海力Electronic and Magnetic Structure of Fe3O4/BiFeO3 Multiferroic Superlattices: First Principles Calculations J. Appl. Phys.null杨华、米文博、白海力、程迎春Electronic and Optical Properties of New Multifunctional Materials via Half-substituted HEMATITE: First Principles Calculatio RSC Advancesnull 王晓姹、马力、米文博Positive Magnetoresistance in Amorphous Ni-CNx/p-Si Heterostructure Appl. Phys. Exp.null段秀峰、米文博、郭载兵、白海力Magnetic and spin-dependent transport properties of reactive sputtered epitaxial Ti1?xCrxN films Acta Materialianull米文博、杨华、程迎春、白海力Ferromagnetic half-metallic characteristic in bulkNi0.5M0.5O (M=Cu, Zn and Cd): A GGA+U study Solid State Commun.null米文博、封秀平、段秀峰、杨华、李岩、白海力Microstructure, magnetic and electrical transport properties of polycrystalline γ'-Fe4N films Thin Solid Filmsnull米文博, 封秀平, 白海力Magnetic properties and Hall effect of reactive sputtered iron nitride nanocrystalline films Journal of Magnetism and Magnetic Materialsnull米文博, 金晶, 白海力Enhanced magnetic properties of annealed Fe48Pt52-C composite films by N incorporation Physica Status Solidi Anull封秀平, 米文博, 白海力Polycrystalline iron nitride films fabricated by reactivefacing-target sputtering: structure, magnetic and electrical transport properties Journal of Applied Physicsnull米文博, 何琲, 李志青, 吴萍, 姜恩永, 白海力Structure and magnetic properties ofN-doped Fe-C granular films Journal of Physics D: Applied Physicsnull省部级以上获奖白海力、米文博、王晓姹、刘宜伟、姜恩永铁磁性复合薄膜的制备、结构和物性研究天津市自然科学奖二等奖2013-03-26知识产权米文博, 叶天宇, 白海力铬掺杂氮化钛磁性半导体多晶薄膜的制备方法中国1米文博, 白海力具有大的霍尔效应的氮化铁薄膜的制备方法中国2米文博,段秀峰,白海力一种具有大磁电阻效应的GdN薄膜及制备方法中国5米文博,金朝,白海力具有电流调控磁电阻效应的Fe3O4/p-Si结构及制备方法中国4 米文博,段秀峰,白海力具有低温磁电阻效应的外延Ti0.53Cr0.47N薄膜材料及制备方法中国3学术专著(米文博王晓姹), 自旋电子学基础, 天津大学出版社2013-05-01戴伍圣纵向课题经费课题名称计算有效作用量、真空能和计数函数的新途径及其在量子场论、统计力学和谱问题中的应用2011-01-01--2013-12-01 负责人:戴伍圣科技计划:国家自然科学基金委拨款单位:国家自然科学基金委合同经费:28课题名称自引力天体物理系统的非广延统计力学研究2007-01-01--2009-12-31负责人:杜九林科技计划:国家自然科学基金委拨款单位:国家自然科学基金委合同经费:28课题名称量子纠缠/ 贝尔不等式及其相关2007-01-01--2009-12-31 负责人:陈景灵科技计划:国家自然科学基金委拨款单位:国家自然科学基金委合同经费:20期刊、会议论文刘彤,李文都,戴伍圣Scattering theory without large-distance asymptotics JHEPnull 戴伍圣,谢汨Calculating statistical distributions from operator relations The statistical distributions of various intermediate statisti Annals of Physicsnull庞海,戴伍圣,谢汨Relation between heat kernel method and scattering spectral method ull邱荣涛,戴伍圣,谢汨Mean first-passage time of quantum transition processes Physica.Anull刘彤,张萍,戴伍圣,谢汨An intermediate distribution between Gaussian and Cauchy distributions Physics Anull庞海, 戴伍圣, 谢汨The pressure exerted by a confined ideal gas J. Phys. Anull本文内容摘自《天津大学理学院普通物理+量子力学考研红宝书》,更多考研资料可登陆网站下载!。

利用脉冲激光沉积技术制备镍纳米颗粒及其生长过程中的应变场模拟

利用脉冲激光沉积技术制备镍纳米颗粒及其生长过程中的应变场模拟

利用脉冲激光沉积技术制备镍纳米颗粒及其生长过程中的应变场模拟袁彩雷;张求龙;江子雄【摘要】利用脉冲激光沉积技术和快速退火成功地制备了镶嵌在非晶Al2O3薄膜中的Ni纳米颗粒,用高分辨率透射电子显微镜观察到镶嵌在非晶Al2O3薄膜中的Ni纳米颗粒,用有限元算法系统地模拟了Ni纳米颗粒生长过程中的应变场分布.研究发现:在Ni纳米颗粒的生长过程中,纳米颗粒受到母体A12O3材料的非均匀的偏应变的作用,而且随着Ni纳米颗粒的长大,纳米颗粒受到母体Al2O3材料的非均匀偏应变也逐渐增加.这种非均匀偏应变对于纳米颗粒的晶格结构和形貌有较大的影响,可以通过调节Ni纳米颗粒生长过程中的应变场来实现对Ni纳米颗粒界面态的调控,从而进一步优化Ni纳米颗粒的物理性能.%Ni nanoparticles embedded in the amorphous Al2O3 matrix were fabricated by using pulsed laser deposition and rapid thermal annealing. The results from high-resolution transmission electron microscope also revealed that the complete isolation of Ni nanoparticles embedded in amorphous A12O3 matrix. The growth strain of Ni nanoparticle embedded in the AI2O3 matrix was investigated. Finite element calculations clearly indicate that the Ni nanoparticle incurs a net deviatoric strain. With the growth of Ni nanoparticle, the larger Ni nanoparticles incur stronger net deviatoric strain, which will have much influence on the structure and morphology of Ni nanoparticles. Strain engineering is an effective tool for tailoring the properties of Ni nanoparticles.【期刊名称】《江西师范大学学报(自然科学版)》【年(卷),期】2012(036)002【总页数】5页(P111-115)【关键词】Ni纳米颗粒;应变场;脉冲激光沉积【作者】袁彩雷;张求龙;江子雄【作者单位】江西师范大学物理与通信电子学院,江西南昌330022;江西师范大学物理与通信电子学院,江西南昌330022;江西师范大学物理与通信电子学院,江西南昌330022【正文语种】中文【中图分类】O484.10 引言随着纳米颗粒尺寸的减小, 颗粒的表面积体积比急剧增大, 表面原子占粒子总原子数比例增大,因此表面态对纳米颗粒性能的影响非常显著[1-3]. 目前, 纳米材料的应用前景引起了科学工作者的高度关注, 已成为新世纪材料科学研究的热点, 并给传统材料产业带来了跨越式发展的重大机遇和挑战[4].近10年来, 由于磁性纳米颗粒具有非常广阔的应用前景, 对于纳米颗粒材料磁特性的研究已经引起了理论和实验学者的广泛关注[5-7]. 由于磁性纳米颗粒具有尺寸小、表面效应显著, 使其表现出许多不同于常规固体材料的新特性[8]. 金属纳米材料, 如具有铁磁性的金属Fe、Co、Ni等, 在磁流体、磁存储媒介、催化作用以及生物医学等科学领域有重要的应用,因而受到广泛的研究, 特别是Ni纳米颗粒, 在磁传感器、信息存储、生物分子分离等领域有着极其重要的应用[9-14]. 目前制备Ni纳米颗粒的方法有以下几种物理和化学方法: 高温分解法、阴极真空喷镀法、化学还原法、声化学沉积法等[15-21]. 近几年, 各种尺寸和形状的纳米颗粒的结构的制备及其特性的研究受到了科学工作者广泛的关注, 其中, 成功地制备各种尺寸和形状的纳米颗粒是一重大挑战[22]. 最近, 人们发现镶嵌在介电材料中的纳米颗粒, 在纳米颗粒的生长过程中总是不可避免地伴随着应变场的产生[23-25],这种应变场会对纳米颗粒的微观结构和形貌产生重要的影响, 进而影响纳米颗粒的物理和化学性能, 如光电磁学性能、催化性能等[26]. 研究工作还发现, 不同尺寸的纳米颗粒在其生长过程中, 受到应变场的分布有很大的不同, 这种应变场的不同对于纳米颗粒的微观结构和形貌都有较大的影响[27]. 但是到目前为止, 对磁性Ni纳米颗粒在其生长过程中的应变场分布还缺乏比较系统的研究. 因此, 成功制备镶嵌在介电母体材料中的Ni纳米颗粒, 并系统地认识Ni纳米颗粒在其生长过程中的应变场分布, 对于磁性Ni纳米材料的应用前景有非常重要的意义.1 实验利用脉冲激光沉积技术和快速退火制备镶嵌在非晶母体Al2O3中的磁性Ni纳米颗粒. 在制备过程中,准分子脉冲激光的波长为248 nm, 频率为5 Hz. 靶是由一个直径为25 mm的圆形的高纯度(质量分数为99.9%)的Al2O3靶材和一块长3 mm的方形Ni靶材组成, 保持Al2O3靶材和Ni靶材始终是物理性的粘结,而非化学性的粘结. 在沉积过程中, 利用一束准分子脉冲激光烧蚀固体靶, Al2O3和Ni组成的靶材缓慢地围绕中心轴旋转, 激光光束交替地烧蚀靶材的2种材料. P型(100)硅衬底先用SC1(NH4OH︰H2O2︰H2O=1︰1︰5)和SC2(HCl︰H2O2︰H2O=1︰1︰5)清洁, 然后浸入质量分数为1%的HF溶液以去除表面氧化层. 在整个沉积的过程中真空室的真空度为7×108 Torr,同时保持硅衬底的温度为室温. 沉积下来的样品在氮气中600 ℃快速退火120 s. 使用2010JEOL高分辨透射电子显微镜(HRTEM)观察这些样品的微观结构.图1(a)为经脉冲激光沉积技术生长样品的高分辨率透射电子显微镜图像, 显然图中没有任何纳米颗粒, 这是因为Ni都以单个的原子散布在Al2O3薄膜母体中, 也就是说Ni原子在低温下并没有成核.然后将这些样品在600 ℃快速退火120 s. 图1(b)为经过600 ℃快速退火样品的高分辨透射电子显微镜图像. 由图1(b)可以看出, 在Al2O3薄膜中, 有许多Ni纳米颗粒, 大部分颗粒都是成核的单晶纳米颗粒.图1(c)为单个的Ni纳米颗粒. 从图1可以发现, 经过在氮气中600 ℃快速退火后形成了镶嵌在Al2O3薄膜中的立方形状的单晶的Ni纳米颗粒. 这是因为, 随着温度的升高, Ni原子形成核的几率也提高, 纳米粒子的密度也会变大; 只要表面能足够, 会形成一些Ni核,而在其周围的Ni原子会通过表面扩散依附到已形成的Ni核上, 团聚成一个更大的Ni纳米颗粒[28].图1 样品的显微镜图像2 模拟与计算Ni纳米颗粒镶嵌在母体材料中产生应变的模型基于以下假设: 一个方形的各向同性的线弹性的纳米晶置于一个无限大各向同性的线弹性的母体材料中, 其中纳米晶是镶嵌在母体材料中的. 假设纳米晶被放在母体材料的一个非常小的空腔中, 由于周围母体材料的原子不能迅速移动以适应纳米晶在生长过程中的体积变化, 因而导致了纳米晶受到了周围母体材料的压缩应变. 用有限元算法(ANSYS软件)系统地模拟了镶嵌在Al2O3母体中的Ni纳米颗粒生长过程中的应变场强度的分布[29-31].在模拟中, Ni和Al2O3的杨氏模量分别为207、360 GPa, 泊松比分别为0.291、0.24. 假定Ni纳米晶的热膨胀系数为1%, 但事实上, 由于纳米晶生长导致初始应变可能远比1%的热膨胀系数大. 在有限元计算中, 假设方形的Ni纳米晶的位置在Al2O3母体的中心, Ni纳米晶和Al2O3母体的交界处是镶嵌的, 考虑Al2O3母体是无限大的和边界固定的.图2是尺寸为5、10、15 nm的Ni纳米颗粒镶嵌在Al2O3薄膜中的X-Y剖面的应力场分布图, 图3是尺寸为5、10、15 nm的Ni纳米晶的X-Y剖面的应变强度图, 图4是5、10、15 nm的Ni纳米晶在Y=0上沿X方向上的应变强度曲线. 显然Ni纳米颗粒受到周围Al2O3母体材料的压缩应变. 随着Ni纳米颗粒的长大, 它所受的周围母体材料的压缩应变强度增强. 对于大尺寸的Ni纳米颗粒, 其表面原子所受的母体材料的压缩应变比中心原子受到的压缩应变更强. 5 nm的Ni纳米颗粒的中心原子受到的应变和表面原子受到的应变几乎相同, 中心原子受到的应变和表面原子受到的应变强度均约为0.1. 这是因为尺寸较小的Ni纳米颗粒具有更大的表面积体积比, 纳米颗粒的表面原子数占纳米颗粒总原子数的比例很大, Ni纳米颗粒受到母体材料的压缩应变被分散到占纳米颗粒总原子数比例很大的表面连续原子上, 因此, 纳米颗粒受到的应变场分布比较均匀. 然而当Ni纳米颗粒生长到10和15 nm时, Ni纳米颗粒表面原子受到的应变明显强于中心原子受到的应变. 另外在Ni 纳米颗粒的棱角处原子受到的应变更大. 当Ni纳米颗粒的尺寸为10 nm时, 纳米颗粒表面原子受到的应变强度为0.229, 中心原子受到的应变强度为0.198, 棱角处原子受到的应变强度为0.283, 中心原子受到的应变比表面原子受到的应变减少了13.5%. 当Ni纳米颗粒的尺寸为15 nm时,纳米颗粒表面原子受到的应变强度为0.375, 中心原子受到的应变强度为0.320, 棱角处原子受到的应变强度为0.469, 中心原子受到的应变比表面原子受到的应变减少了14.9%. 对于尺寸较大的Ni纳米颗粒,表面积体积比比较小, 纳米颗粒的表面原子数占纳米颗粒总原子数的比例较少, Ni纳米颗粒应变被分散在占纳米颗粒总原子数比例较少的表面连续原子上, 因而导致Ni纳米颗粒表面原子受到的应变比中心原子受到的应变强. 因此, 在Ni纳米颗粒的生长过程中, 纳米颗粒受到母体Al2O3材料的非均匀的偏应变的作用, 而且随着Ni纳米颗粒的长大, 纳米颗粒受到母体Al2O3材料的非均匀偏应变也逐渐增加.这种存在的非均匀偏应变对于纳米颗粒的晶格结构和形貌有较大的影响, 从而极大地影响其物理性能[32].图2 直径为5、10、15 nm的Ni纳米晶的X-Y剖面的应变场分布图3 分别为5 nm(a)、10 nm(b)、15 nm(c)Ni纳米晶的X-Y剖面的应变强度图图4 分别为5、10、15 nm Ni纳米晶在Y=0上沿X方向上的应变强度曲线图3 结论用脉冲激光沉积和快速退火技术成功制备了镶嵌在Al2O3薄膜上的Ni纳米颗粒. 用高分辨透射电子显微镜观察发现这些Ni纳米晶具有面心立方的晶格结构. 用有限元算法研究Ni纳米晶在生长过程中的应变场分布, 发现在Ni纳米颗粒的生长过程中,纳米颗粒受到母体Al2O3材料的非均匀的偏应变的作用, 而且随着Ni纳米颗粒的长大, 纳米颗粒受到母体Al2O3材料的非均匀偏应变也逐渐增加. 这种存在的非均匀偏应变对于纳米颗粒的晶格结构和形貌有较大的影响. 因此, 系统地研究磁性Ni 纳米材料的应变场分布, 对有效地调控其物理化学性能有着非常重大的意义.4 参考文献【相关文献】[1] Fujii M, Inoue Y, Hayashi S, et al. Hopping conduction in SiO2 films containing C, Si, and Ge clusters [J]. Appl Phys Lett, 1996, 68: 3749-3751.[2] Franzo G, Irrera A, Moreira E C, et al. Electroluminescence of silicon nanocrystals in MOS structures [J]. Appl Phys A Mater Sci Process, 2002, 74: 1-5.[3] Yuan Cailei, Cai H, Lee P S, et al. Tuning photoluminescence of Ge/GeO2 core/shell nanoparticles by strain [J]. J Phys Chem C, 2009, 113: 19863-19866.[4] Van T Hoof, Hou M. Structural and thermodynamic properties of Ag-Co nanoclusters [J]. Phys Rev B, 2005, 72: 115434.[5] Raksha Sharma, Komilla Suri, Tandon R P, et al. Magnetic relaxation studies in organic-inorganic nanoclusters [J]. J Appl Phys, 2006, 99: 24311.[6] Chepulskii R V, Butler W H. Temperature and particle-size dependence of the equilibrium order parameter of FePt alloys [J]. Phys Rev B, 2005, 72: 134205.[7] Volokitin Y, Sinzig J, DeJongh L J, et al. Quantum-size effects in the thermodynamic properties of metallic nanoparticles [J]. Nature, 1996, 384: 621-623.[8] Pileni M P. Magnetic fluids: Fabrication, magnetic properties, and organization of nanocrystals [J]. Adv Funct Mater, 2001, 11: 323-336.[9] Diandra L, Leslie-Pelecky, Reuben D. Magnetic properties of nanostructured materials [J]. Chem Mater, 1996, 8: 1770-1783.[10] Skomski R. Nanomagnetics [J]. J Phys Condens Matter, 2003, 15: R841.[11] Wellner A, Paillard V, Bonafos C, et al. Stress measurements of germanium nanocrystals embedded in silicon oxide [J]. J Appl Phys, 2003, 94: 5639-5642.[12] Chew H G, Zheng F, Choi W K, et al. Influence of reductant and germanium concentration on the growth and stress development of germanium nanocrystals in silicon oxide matrix [J]. Nanotechnology, 2007, 18: 65302.[13] Che S L, Takada K, Takashima K, et al. Preparation of dense spherical Ni particles and hollow NiO particles by spray pyrolysis [J]. J Mater Sci, 1999, 34: 1313-1318.[14] Thompson G B, Banerjee R, Zhang X D, et al. Chemical ordering and texture in Ni–25 at% Al thin films [J]. Acta Mater, 2002, 50: 643-651.[15] Wu Szuhan, Chen Donghwang. Synthesis and Stabilization of Ni Nanoparticles in a Pure Aqueous CTAB Solution [J]. Chem Lett, 2004, 33: 406.[16] Margeat O, Amiens C, Chaudret B, et al. Chemical control of structural and magnetic properties of cobalt nanoparticles [J]. Hem Mater, 2005, 17: 107-111.[17] Green M, O’Brien P. A no vel metalorganic route to nanocrystallites of zinc phosphide [J]. Chem Mater, 2001, 13: 4500-4505.[18] Hou Yanglong, Gao Song. Monodisperse nickel nanoparticles prepared from a monosurfactant system and their magnetic properties [J]. J Mater Chem, 2003, 13: 1510-1512.[19] Ramesh S, Koltypin Y, Prozorov R, et al. Sono-chemical deposition and characterization of nanophasic amorphous nickel on silica microspheres [J]. Chem Mater, 1997, 9: 546-551.[20] Choi W K, Ng V, Ng S P, et al. Raman characterization of germanium nanocrystals in amorphous silicon oxide films synthesized by rapid thermal annealing [J]. J Appl Phys, 1999, 86: 1398-1403.[21] Wellner A, Paillard V, Bonafos C, et al. Stress measurements of germanium nanocrystals embedded in silicon oxide [J]. J Appl Phys, 2003, 94: 5639-5642.[22] Chew H G, Zheng F, Choi W K, et al. Influence of reductant and germanium concentration on the growth and stress development of germanium nanocrystals insilicon oxide matrix [J]. Nanotech-nology, 2007, 18: 65302.[23] Yuan Cailei, Cai H, Lee P S, et al. Tuning Photoluminescence of Ge/GeO2 Core/Shell Nanoparticles by Strain [J]. J Phys Chem C, 2009, 113: 19863-19866.[24] Yuan Cailei, Liu Qing, Xu Bo. Strain-induced structural phase transition of Si nanoparticles [J]. J Phys Chem C, 2011, 115, 16374-16377.[25] Yuan Cailei, Lee P S, Ye S L. Formation, photoluminescence and charge storage characteristics of Au nanocrystals embedded in amorphous Al2O3 matrix [J]. Europhys Lett, 2007, 80: 67003.[26] Benabbas T, Androussi Y, Lefebvre A. A finite-element study of strain fields in vertically aligned InAs islands in GaAs [J]. J Appl Phys, 1999, 86: 1945.[27] Pei Q X, Lu C, Wang Y Y. Effect of elastic anisotropy on the elastic fields and vertical alignment of quantum dots [J]. J Appl Phys, 2003, 93: 1487-1492.[28] Shin H, Lee W, Yoo Y H. Comparison of strain fields in truncated and un-truncated quantum dots in stacked InAs/GaAs nanostructures with varying stacking periods [J]. J Phys Condens Matter, 2003, 15: 3689.[29] Yuan Cailei, Xu Bo, Lei W. Strain-induced direct band gap LaAlO3 nanocrystals [J]. Materials Letters, 2012, 68: 392-394.。

材料领域英文术语

材料领域英文术语

metal 金属ceramic 陶瓷polymer 聚合物Composites 复合材料Semiconductors 半导体Biomaterials 生物材料Processing 加工过程Structure 组织结构Properties 性质Performance 使用性能Mechanical properties力学性能Electrical properties 电性能Thermal behavior 热性能Magnetic properties 磁性能Optical properties 光性能Deteriorative characteristics 老化特性Atomic mass unit (amu) 原子质量单位Atomic number 原子数Atomic weight原子量Bohr atomic model 波尔原子模型Bonding energy 键能Coulombic force 库仑力Covalent bond 共价键Dipole (electric) 偶极子electronic configuration 电子构型electron state 电位Electronegative 负电的Electropositive 正电的Ground state 基态Hydrogen bond 氢键Ionic bond 离子键Isotope 同位素Metallic bond 金属键Mole 摩尔Molecule 分子Pauli exclusion principle 泡利不相容原理Periodic table 元素周期表Polar molecule 极性分子Primary bonding 强键Quantum mechanics 量子力学Quantum number 量子数Secondary bonding 弱键valence electron 价电子van der waals bond 范德华键Wave-mechanical model 波粒二象性模型Allotropy 同素异形现象Amorphous 无定形Anion 阴离子Anisotropy 各向异性atomic packing factor(APF) 原子堆积因数body-centered cubic (BCC) 体心立方结构Bragg’s law 布拉格定律Cation 阳离子coordination number 配位数crystal structure 晶体结构crystal system 晶系crystalline 晶体的diffraction 衍射face-centered cubic (FCC) 面心立方结构grain 晶粒grain boundary 晶界hexagonal close-packed (HCP) 六方密堆积isotropic 各向同性的lattice 晶格lattice parameters 晶格参数miller indices 密勒指数noncrystalline 非结晶的octahedral position 八面体配位polycrystalline 多晶的polymorphism 多晶形single crystal 单晶tetrahedral position 四面体配位unit cell 晶胞covalent bonds: 共价键hydrogen bonds: 氢键van der Waals bonds: 范德华键(分子键)Hydrocarbons: 烃: 由碳和氢组成的物质methane (CH4) 甲烷Ethylene C2H4 乙烯acetylene, C2H2 乙炔Unsaturated Hydrocarbons: 不饱和烃Saturated Hydrocarbons: 饱和烃Paraffin: 石蜡Macromolecule: 高分子Isomerism: 同质异构Mer: 链节:组成聚合物链重复单位的原子集合。

物理杂谈 (62)

物理杂谈 (62)

物理漫談 (S0547) (3,0)物理與哲學、實驗物理-天文學、理論物理-氣體動力學、相對論與重力理論、理論物理-重力理論相對論、凝態物理、高能物理。

Physics and Philosophy, Experimental Physics and Astronomy, Theoretical Physics and thermodynamics, Relativity and Gravity, Gondens-matter Physics, High-energy Physics.光電漫談 (S0640) (3,0)光學與半導體基礎知識。

包含:光電半導體、顯示器裝置、光纖光學及其元件、積體光學、光電積體電路、光儲存裝置、電荷耦合元件及其應用、光子晶體、微光學元件、近場光學、非線性光學、生醫光電等。

Fundamentals of optical and semiconductor; Covers: Photoelectronic semiconductors, Display devices, Fiber optics and its components, Integrated optics, Optoelectronic integrated circuit, Optical storage devices, Charge coupled devices and its application, Photonic crystal, Micro-optical devices, Near field optics, Nonlinear optics, Electro-optics on medicine.天文學 (S0041) (0,3)宇宙概觀、太陽系、星距量測、星的性質、分類與演化、星雲、星團、銀河、系結構分類、宇宙論、天文台及望遠鏡。

Overview of Universe; Solar System; Inter-Stellar Distance; Properties of Stars; Classification and Evolution; Star Nebulae; Star Cluster, Structure and Classification of Glaxies; Cosmology; Observateries and Telescopes.力學(二) (0,3) / 應用力學(二)(0,3)中心力下的運動、多粒子系統動力學、剛體動力學、耦合振動、非線性振動 (選擇)、非慣性參考座標系中的運動 (選擇)、連續系統 (選擇)。

Nuclear magnetic resonance(核磁共振)

Nuclear magnetic resonance(核磁共振)

Applicaton in Medical Science
• 1. Detecion and diagnosis of heart diseases, cerebrovascular accident and ascular diseases. 侦测及诊断心脏疾病、脑血管意外及血管疾病
• 2. Detecion and diagnosis of organ diseases in chest and abdominal cavity 胸腔及腹腔的器官疾病的侦测与诊断
• nuclei ['njuːklɪaɪ] 原子核 (nucleus的复数形式) • re-emit [rii'mit] 重发射 • isotope ['aɪsətəʊp] 同位素
• A key feature of NMR is that the resonance frequency(共振频率) of a particular substance is directly proportional to the strength of the applied magnetic field. It is this feature that is exploited in imaging techniques; if a sample is placed in a non-uniform magnetic field then the resonance frequencies of the sample's nuclei depend on where in the field they are located.
• spectroscopy [spek'trɒskəpɪ] 光谱学
Magnetic resonance imaging (NRI)

洪特规则和泡利原理能量最低原理

洪特规则和泡利原理能量最低原理

洪特规则和泡利原理能量最低原理The Hund’s rule and the Pauli exclusion principle are both fundamental principles in quantum mechanics that govern the arrangement of electrons in an atom. These principles play a crucial role in determining the energy levels and stability of atoms and molecules. Hund's rule states that when filling orbitals of the same energy, electrons will occupy separate orbitals with parallel spins before they start pairing up. This is based on the idea that electrons repel each other due to their negative charge, and thus prefer to stay in different orbitals. 洪特规则规定,在填充具有相同能量的轨道时,电子会在开始成对之前,占据具有平行自旋的不同轨道。

这是基于电子由于其负电荷互相排斥的想法,并因此倾向于留在不同的轨道中。

On the other hand, the Pauli exclusion principle states that no two electrons in an atom can have the same set of four quantum numbers. Put simply, this means that each electron in an atom must have its own unique set of quantum numbers, which include the principal quantum number, angular momentum quantum number, magnetic quantum number, and spin quantum number. In practical terms, this principle leads to the limitation of two electrons perorbital, with opposite spins. 另一方面,泡利排斥原理规定一个原子中的任意两个电子不能具有相同的四个量子数集。

磁性金属有机骨架材料FeMPC_的制备及其吸附性能研究

磁性金属有机骨架材料FeMPC_的制备及其吸附性能研究

Abstract: Firstlyꎬthe metal ̄organic framework material MIL ̄101( Fe) was prepared by hydrother ̄
mal synthesis methodꎬand then the magnetic metal ̄organic framework material FeMPC was pre ̄
及其吸附性能研究
唐祝兴1 ꎬ宋宏权1 ꎬ张岐龙1 ꎬ董 华2
(1. 沈阳理工大学 环境与化学工程学院ꎬ沈阳 110159ꎻ 2. 西北工业集团有限公司ꎬ西安 710043)
摘 要: 首先采用水热合成法制备金属有机骨架材料 MIL ̄101 ( Fe) ꎬ然后通过煅烧 MIL ̄101
( Fe) 制备磁性金属有机骨架材料 FeMPCꎬ并用于吸附染料废水中的亚甲基蓝ꎮ 使用扫描电
ꎮ MOFs 材料比表面积大、
孔隙率高ꎬ结构组成种类繁多ꎬ易于实现化学改
性ꎬ因此在选择性吸附领域备受重视ꎮ
为提高 MOFs 材料的稳定性ꎬ研究者通过对
有机配体进行修饰ꎬ合成了磁性金属有机骨架材料
吸附ꎬ探究吸附剂用量、振荡时间、pH 等因素对吸
附性能的影响ꎬ确定适宜的吸附条件ꎮ
1 实验部分
1. 1 实验主要试剂与仪器
衍生的黑碳材料 FeMPCꎮ 与大多数 MOFs 相比ꎬ
速ꎬ世界各地水体污染日益严重
[1 - 2]
ꎮ 工业废水
的废水是纺织工业的主要污染源 [3 - 4] ꎮ 这些工业
的环境污染十分严重
[5 - 6]
ꎮ 染料废水成分复杂ꎬ
模型ꎬ吸附动力学符合拟二级动力学模型ꎬ属于化
本文首先以水热合成法合成 MIL ̄101 ( Fe) ꎬ

交换相关泛函 英语

交换相关泛函 英语

Exchange-Related Functionals in QuantumMechanicsIn the realm of quantum mechanics, exchange-related functionals play a pivotal role in understanding the interactions and properties of particles. These functionals describe the behavior of particles when they are interchanged or swapped within a given system. The exchange effect is particularly significant in areas such as electron exchange in chemistry, spin exchange in condensed matter physics, and particle exchange in quantum field theory.In the context of chemistry, the exchange-related functionals are often associated with the Pauli exclusion principle, which states that no two electrons can occupy the same quantum state simultaneously. This principle gives rise to the electron exchange interaction, which is responsible for the stability of multi-electron systems and the formation of chemical bonds. The exchange-correlation energy, which is a component of the total energy of a system, accounts for the interactions between electronsthat arise due to their mutual exclusion.In condensed matter physics, spin exchange functionals describe the interactions between magnetic moments or spins of particles. These interactions are crucial in determining the magnetic properties of materials, such as ferromagnetism, antiferromagnetism, and spin glasses. The exchange interaction is also responsible for the emergence of quantum spin liquids, which exhibit exotic magnetic behaviors due to strong spin correlations.In quantum field theory, particle exchange functionals are key in understanding the dynamics of particles andtheir interactions. These functionals describe the probabilities of particles being created, annihilated, or exchanged between different states. They play a fundamental role in quantum field theories such as the Standard Model, which describes the fundamental forces and particles in nature.The study of exchange-related functionals requires advanced mathematical techniques and computational methods. These functionals are often expressed as integrals over space and time, involving complex wavefunctions and operators. The development of accurate and efficientmethods for evaluating these functionals is crucial for making predictions and understanding the behavior of quantum systems.In conclusion, exchange-related functionals are essential in quantum mechanics, providing insights into the interactions and properties of particles. They underlie various phenomena in chemistry, physics, and quantum field theory, and their study requires advanced mathematical and computational techniques. The continuous development of methods for evaluating these functionals holds the promise of deeper understanding and new discoveries in the quantum realm.**交换相关泛函在量子力学中的应用**在量子力学领域,交换相关泛函对于理解粒子间的相互作用和性质起着至关重要的作用。

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arXiv:cond-mat/0508685v1 [cond-mat.stro
College of Chemistry and Molecular Engineering, State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking University, Beijing 100871, China By means of the density matrix renormalization group (DMRG) method, the magnetic properties of the J-J-J′ quantum Heisenberg chains with spin S = 1/2, 1, 3/2 and 2 in the ground states are investigated in the presence of a magnetic field. Two different cases are considered: (a) when J is antiferromagnetic and J ′ is ferromagnetic (i.e. the AF-AF-F chain), the system is a ferrimagnet. The plateaus of the magnetization are observed. It is found that the width of the plateaus decreases with increasing the ferromagnetic coupling, and disappears when J ′ /J passes over a critical value. The saturated field is observed to be independent of the ferromagnetic coupling; (b) when J is ferromagnetic and J ′ is antiferromagnetic (i.e. the F-F-AF chain), the system becomes an antiferromagnet. The plateaus of the magnetization are also seen. The width of the plateaus decreases with decreasing the antiferromagnetic coupling, and disappears when J ′ /J passes over a critical value. Though the ground state properties are quite different, the magnetization plateaus in both cases tend to disappear when the ferromagnetic coupling becomes more dominant. Besides, no fundamental difference between the systems with spin half-integer and integer has been found. PACS number(s): 75.10.Jm, 75.30.Kz
Magnetic Properties of J-J-J′ Quantum Heisenberg Chains with Spin S = 1/2, 1, 3/2 and 2 in a Magnetic Field
Bo Gu and Gang Su∗
College of Physical Sciences, Graduate University of Chinese Academy of Sciences, P. O. Box 4588, Beijing 100049, China
I.
INTRODUCTION
Low-dimensional quantum spin systems have been attracting both experimental and theoretical interest in the last decades due to an interplay of strong quantum fluctuations and topology. Several theoretical predictions for the low-dimensional quantum spin chains have been verified by experimental studies. For the Heisenberg antiferromagnetic (HAF) chains with spin S = half − integer, the celebrated Lieb, Schultz and Mattis theorem showed that the excitation of the system is gapless [2]. For the HAF chains with spin S = integer, the excitation from the singlet ground state to the triplet excited state was conjectured to be gapful, now known as Haldane conjecture[3]. Another interesting phenomenon in HAF spin chains is the occurrence of the magnetization plateaus, that can be viewed as an essentially macroscopic quantum phenomenon, and has gained much attention recently. A decade ago, Hida has considered an S = 1/2 HAF chain with exchange coupling of 3-site translational invariance in the presence of an applied magnetic field, and uncovered a plateau in the magnetization curve at 1/3 of the saturation magnetization[4]. Slightly after Hida’s numerical calculation on the plateau of the S = 1/2 F-F-AF chain, an analytical approach was done by Okamoto[5]. These results lead to a more general necessary condition for the appearance of the magnetization plateaus which was proved by Oshikawa, Yamanaka and Affleck[6]. It tells us that for the HAF spin chains with S = integer or half − integer, the magnetization curve can have plateaus at which the magnetization per site m is topologically quantized by n(S − m) = integer, (1)
where S is the magnitude of the spin, and n is the period of the ground state determined by the explicit spatial structure of Hamiltonian. At the plateaus, the spin gaps open, that can be in some sense regarded as a kind of generalization of the Haldane conjecture. Similar to the quantum Hall effect, the magnetization plateau is another striking example of the macroscopic quantum phenomenon, in which magnetization is quantized to fractional values of the saturated magnetization value and is a function of the magnetic field. The magnetization plateaus are predicted and observed in many low-dimensional spin systems. Among others, a magnetization plateau at half the saturation magnetization was observed in S = 1 HAF bond-alternating chain compounds [Ni2 (dpt)2 (µ − ox)(µ − N3 )](PF6 ) (abbreviated as NDOAP) and [Ni(333 − tet)(µ − NO2 )]ClO4 (abbreviated as NTENP), where the experimental result is in agreement with the numerical calculations[7, 8, 9]; the ferrimagnetic mixed spin chains such as the bimetallic chain MM′ (pbaOH)(H2 O)nH2 O and the organic compound Mn(hfas)2 3 (3R)2 show quantum magnetization plateaus[10, 11, 12, 13, 14]; the magnetization plateaus are also found in p-merized chains and ladders[15, 16, 17, 18]. The effect of randomness on magnetization process also attracts much theoretical interest [19, 20]. One-dimensional (1D) helical spin system Co(hfac)2 NITPhOMe shows some interesting magnetic behaviors, where one of the unusual properties is that the magnetization shows plateaus at zero and 1 3 of the saturation if a magnetic field is applied along the helical axis, but no plateaus if the field is applied in the plane perpendicular to that axis[21]. Another intriguing topic in 1D spin systems is concerned with the
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