纪念穆斯堡尔效应发现40周年

文章论述了穆斯堡尔效应的发现和穆斯堡尔谱学的基本原理，并对穆斯堡尔谱学在材料科学、生物医学、考古学和地质矿物学中的应用进行了讨论     

穆斯堡尔谱法及其应用

文章简介了穆斯堡尔效应、穆斯堡尔谱的产生以及穆斯堡尔效应的应用 ,说明它不仅在理论上具有深刻的意义 ,又有着广泛的应用价值 .     

穆斯堡尔效应在地质和矿物学中的研究动态

本文简要地介绍了穆斯堡尔效应在地质矿物学中近年来国内外的研究动态。结果表明，地质矿物学仍是穆斯堡尔谱学应用研究中非常活跃的领域之一。     

同步辐射穆斯堡尔谱学

同步辐射穆斯堡尔谱自从1985年取得突破后, 经历了20多年的长足发展, 已经成为穆斯堡尔谱学的一个成熟的分支。 目前同步辐射穆斯堡尔谱学由两个部分构成: 基于相干核共振散射机制的时域穆斯堡尔谱学和基于非相干非弹性核共振散射机制的X射线谱学。 第三代同步加速器的出现促进了时域穆斯堡尔谱学的发展, 测量得到穆斯堡尔激发态寿命τ期间衰变计数率与时间的关系, 观测到一些有趣的现象。 同步辐射穆斯堡尔谱既能做常规透射谱学研究, 测量各种超精细相互作用及f_LM, δ_SOD等穆斯堡尔参数, 也能利用非弹性核共振散射测量固体的声子谱, 并且也能测出f_LM和 δ_SOD及力常数等, 时域谱和非相干谱的测量精度都高于常规穆斯堡尔谱。 The idea of using synchrotron radiation as a Mössbauer source experienced a breakthrough in 1985, followed by steady development for more than 20 years. Synchrotron Mössbauer spectroscopy consists of two areas. The first one is the so called time domain Mössbauer spectroscopy based on coherent nuclear resonant scattering which permits determination of hyperfine interactions and other Mössbauer parameters such as f_LM and δ_SOD. The other is incoherent nuclear resonant inelastic X ray scattering, which provides vibration information of atoms in a solid, i.e., the phonon density of states. All the experiments have better accuracy than that obtained in conventional Mssbauer spectroscopy.     

穆斯堡尔谱学的近期前景

本文讨论了穆斯堡尔谱学应用的突出特点、显著特征、发展趋势、最新进展以及我国穆斯堡尔谱学界的基本情况。     

穆斯堡尔成象技术

通常的穆斯堡尔谱给出的是在样品范围内经空间积分的微观结构信息．近年来提出二类基于穆斯堡尔谱学的成象方法，用以确定物相的空间分布，达到实现空间分辨可达微米量级的穆斯堡尔成象．它为固体物理、材料科学、矿物学等提供一种新手段．该文介绍这个刚开始发展的新领域的现状和前景．     

匀加速穆斯堡尔谱仪系统及穆斯堡尔谱的精确测量

描述穆斯堡尔谱仪系统原理、结构、驱动机制，对探测器的选择与14．4keV能量窗口的甄别、放射源匀加速运动、驱动波形与同步问题进行了分析，指出谱仪使用和调整时应注意的问题，并就其对穆斯堡尔谱精确测量的影响进行了探讨。     

穆斯堡尔谱学研究进展

本文评述1988～90年穆斯堡尔谱学的进展.穆斯堡尔效应的应用继续扩展到几乎所有的科学领域.论文主要涉及基础研究,有些涉及工业应用和材料研究.论文年发表数持续快速增长.在这期间由每年发表1500篇增至1800篇.国际会议频繁,并且大量被评述.它们总的表明,这个研究领域是非常活跃的. The developments and achievements in M(?)ssbauer spectroscopy during recent 3 years are reviewed.The use of the M(?)ssbauer effect is still increasing and expanding to all subjects of sciences.Most of the papers concern with fundamental research,some refer to in- dustrial applications and many are about material research.The growth in the M(?)ssbauer lit- erature continues rapidly.During this period of time the number of M(?)ssbauer publications increased from ...     

快重离子辐照效应的穆斯堡尔谱学研究

概述了利用穆斯堡尔效应开展的固体材料快重离子辐照效应研究的部分结果 ,并对建立在兰州重离子加速器 (HIRFL)上的在束穆斯堡尔谱学研究装置及其应用作了简要的介绍.Mssbauer spectroscopy study of irradiation effects induced by swift heavy ions in solid materials were briefly presented.Amorphization phenomenon of yttrium iron garnet irradiated by 1 GeV Ar ions has been investigated. For the first time, the nearly complete amorphous state was observed. Stainless steel 316L samples were irradiated with 54 MeV C ions and phase transformation of the samples was observed. HT 9 ferrite steel was irradiated with 510 MeV C ions. Its phase...     

铋系超导体超精细相互作用研究

利用变温穆斯堡尔谱研究了铋系高Ｔ_c氧化物超导体在正常态上及正常态－超导态转变过程中晶格振动的性质。穆斯堡尔谱无反冲因子的测量结果表明，在超导转变温度以上的１２０Ｋ和２００Ｋ附近的两个温区上，分别出现了明显的铜－氧层晶格软化效应。这种晶格振动的异常行为，是超导转变的前驱效应。同质异能移位和无反冲因子得到德拜温Θ_D为３１０－３５０Ｋ。测量同质异能移位、四极劈裂和谱线线宽也观察到超导转变前晶格的反常变化行为和ｄ电子的离域效应。 关键词：     

On mossbauer dynamics in Nb3Sn

We compare the anharmonic Lamb Mossbauer factor and the q-Lamb Mossbauer factor by studying the anharmonicity observed in the f-factor data of Nb₃Sn. We also show that this anharmonicity does not arise due to the presence of potential.     

Mossbauer analysis of deformation dissolution of the products of cellular decomposition in high-nitrogen chromium manganese austenite steel

Methods of Mossbauer spectroscopy and electron microscopy analysis of high-nitrogen chromium manganese steel FeMn₂₂Cr₁₈N_0.8 have been used to investigate the processes of dissolution of the products of cellular decomposition in austenite matrix upon severe deformation under the conditions of dry sliding friction and shear under pressure in Bridgman anvils. Deformation-induced redistribution of nitrogen from the chromium nitrides to interstitial positions of the quenched and preliminary aged steel has been determined. According to the data of Mossbauer analysis the depth of dissolution of chromium nitrides and the increase of content of nitrogen in steel matrix upon friction is 10?μn and more. Aging decreases the amount of nitrogen which transfers to the solid solution under deformation. This is a factor of the enhanced adhesive wear in the aged samples.     

Concentration Dependence of Room Temperature Magnetic Ordering in Dilute Fe: Ge1 − x Te x Alloy

Hyperfine interaction techniques like Mossbauer spectroscopy are very sensitive tools to study the local probe interactions in dilute magnetic semiconductors. We report here a Mossbauer study on the concentration dependence in Fe_0.008Ge_{1 − x} Te _x for x = 0, 0.008, 0.016, 0.03 and 0.05. At room temperature magnetic interactions were observed for all concentrations of Te and the population of magnetic site was found to increase gradually with the Te concentration. A constant magnetic hyperfine field of 136 KOe was found. A quadrupole doublet due to the FeTe₂ compound phase was also seen.     

Electromagnetic wave absorbing properties and hyperfine interactions of Fe–Cu–Nb–Si–B nanocomposites

The Fe–Cu–Nb–Si–B alloy nanocomposite containing two ferromagnetic phases(amorphous phase and nanophase phase) is obtained by properly annealing the as-prepared alloys. High resolution transmission electron microscopy(HRTEM) images show the coexistence of these two phases. It is found that Fe–Si nanograins are surrounded by the retained amorphous ferromagnetic phase. M¨ossbauer spectroscopy measurements show that the nanophase is the D03-type Fe–Si phase, which is employed to find the atomic fractions of resonant57 Fe atoms in these two phases. The microwave permittivity and permeability spectra of Fe–Cu–Nb–Si–B nanocomposite are measured in the frequency range of 0.5 GHz–10 GHz. Large relative microwave permeability values are obtained. The results show that the absorber containing the nanocomposite flakes with a volume fraction of 28.59% exhibits good microwave absorption properties. The reflection loss of the absorber is less than-10 dB in a frequency band of 1.93 GHz–3.20 GHz.     

Fe基合金与金刚石单晶生长

 本文通过Fe基催化剂在生长金刚石单晶中获得的不同现象与Fe基合金晶格常数、组分、磁距、Mossbauer谱相比较，揭示了Fe基催化剂常温常压下磁性质与金刚石单晶生长的关系。     

Studies on some alkali-phosphate glasses containing antimony and iron oxides

The effect of heat treatment on the Fe²⁺/Fe³⁺ ratio in some alkali phosphate glasses containing antimony and iron oxides has been investigated. Differential thermal analysis, Mossbauer spectroscopy, magnetic susceptibility and density measurements as well as the molar volume calculations were used in this study. The obtained data indicate that all glasses show approximately unchangeable stability. It is found, from the area under the Mossbauer absorption spectra that ferrous transformed gradually to ferric ions and the transformation rate constant was found to be 48 min⁻¹. The elapsed time was found to be 160 min. This transformation represents a first-order solid state reaction. The molar magnetic susceptibility measurements confirm the above results.     

A structural, magnetostrictive and M(o)ssbauer study of Tb0.3Dy0.7(Fe0.9T0.1)1.95 alloys

The effect of ⅢA metal and transition metal T substitution for Fe on crystal structure, magnetostriction and spontaneous magnetostriction, anisotropy and spin reorientation of a series of polycrystalline Tb0.3Dy0.7(Fe0.9T0.1)1.95 (T = Mn, Fe, Co, B, Al, Ga) alloys at room temperature were investigated systematically. It was found that the primary phase of the Tb0.3Dy0.7(Fe0.9T0.1)1.95 alloys is the MgCu2-type cubic Laves phase structure for different substitution. The magnetostriction λs decrases greatly for the substitution of IIIA metal B, Al and Ga, but is saturated more easily for Al and Ga substitution, showing that the Al and Ga substitution is beneficial to a decrease in the magnetocrystalline anisotropy of Tb0.3Dy0.7(Fe0.9T0.1)1.95 alloys. However, the substitution of transition metal Mn and Co decreases slightly the magnetostriction λs. It was also found that the effect of different substitutions on the spontaneous magnetostriction λ111 is distinct. The analysis of the Mossbauer spectra indicates that the easy magnetization direction in the {110} plane deviates slightly from the main axis of symmetry for Al and Ga substitution, namely spin reorientation, but it does not change evidently for B, Mn and Co substitution.     

FeMn粉末触媒对合成金刚石的影响

 利用FeMn粉末触媒在国产六面顶压机上进行了合成金刚石单晶的实验,研究了高温高压条件下（5.7 GPa、1 550 ℃）,石墨-FeMn粉末触媒体系中金刚石单晶的生长特性。通过光学成像显微镜观测表明：合成出的金刚石单晶呈浅黄色,晶形完整,且都是八面体,晶体里含有白色物质,粒度集中在0.3~0.5 mm;通过扫描电镜观测了晶体的表面形貌,表面有熔坑;通过穆斯堡尔谱,发现粉末触媒里主要是FeMn合金和独立状态的Fe,金刚石内部主要是Fe和Fe₃C;利用X射线荧光光谱,检测出样品里有Fe和Mn元素。     

Tl2Ba2Ca2Cu3O10的化学键性质和同质异能位移研究

在Tl2Ba2Can-1CunO2n 4(n=1,2,3,4)系列超导性氧化物中,Tl2Ba2Ca2Cu3O10具有最高Tc值(125 K)．利用电介质的平均能带模型计算了Tl2Ba2Ca2Cu3O10的局域化学键参数,得到Cu(1)-O键的共价性为0．561,Cu(2)-O键的平均共价性为0．296．应用化学环境因子计算了57Fe在Tl2Ba2Ca2Cu3O10中的穆斯堡尔同质异能位移,证实了57Fe在低掺杂时以Fe3 和Fe4 离子形式占据Cu(1)位置,而在高掺杂时以Fe3 和Fe4 离子形式分别占据Cu(1)和Cu(2)位置．结果表明,化学键理论计算有助于复杂晶体的穆斯堡尔谱的正确分析．     

Mossbauer, Raman and X-ray diffraction studies of superparamagnetic NiFe2O4 nanoparticles prepared by sol-gel auto-combustion method

Superparamagnetic nickel ferrite single phase nanoparticles with the average crystallite size of ∼9 nm have been synthesized at a low temperature (220 °C) by the sol-gel auto-combustion method. In the present study the as prepared powder was further calcined at different temperatures for 4 h, resulting in nanoparticles of larger size. The nanoparticles exhibited superparamagnetic behavior and changes in cation distribution as revealed by the Mossbauer, Raman and X-ray diffraction studies. The Mossbauer spectra collected at 5 K and under 5 T applied magnetic field showed mixed spinel structure and canted spin order for the nanoparticles, whereas there is collinear spin order with inverse spinel structure for larger particles. The vibrational spectra of the nanoparticles showed a redshift and broadening in the Raman line shape due to confinement effects.