共查询到16条相似文献,搜索用时 750 毫秒
1.
本文叙述了用偏振中子衍射方法对Fe83B17非晶合金和中子衍射方法对Ni64B36非晶合金的结构研究。由实验数据计算了每种合金的偏干涉函数(PSF)Sij(Q),和偏简约径向分布函数Gij(r)。并得到原子短程结构上的各项参数。在此基础上,讨论了这一类非晶态合金的结构模型,计算了其一种模型简单单元的中子衍射散射强度,并和实验所得的结果作了比较。
关键词: 相似文献
2.
3.
4.
5.
本文叙述了用偏振中子衍射方法对Fe_83B_17非晶合金和中子衍射方法对Ni_64B_36非晶合金的结构研究。由实验数据计算了每种合金的偏干涉函数(PSF) S_(ij)(Q),和偏简约径向分布函数G_(ij)(r)。并得到原子短程结构上的各项参数。在此基础上,讨论了这一类非晶态合金的结构模型,计算了其一种模型简单单元的中子衍射散射强度,并和实验所得的结果作了比较。 相似文献
6.
7.
本工作用X射线散射技术研究了金属一类金属玻璃合金Pd77Si16.5Ag6.59,Co42.9Ni27.3Fe7.8Si8B14和Co50.7Ni19.5Fe7.8Si6B16的结构。求出了它们的干涉函数I(s)和原子径向分布函数RDF(r),并由此获得了有关结构信息的原子平均距离、最近邻配位数和短程有序畴半径。此外,对这些合金的RDF(r)第一峰作了高斯分布拟合,求得了比较好的拟合方程,并用近似方法估算了其中金属-金属原子间的配位数。
关键词: 相似文献
8.
9.
10.
11.
D. Adhikari 《Phase Transitions》2013,86(4):308-314
The disorder in thermodynamic and microscopic structure of liquid Cu–Pd alloy at 1350?K has been studied using regular associated solution model. For this, we have calculated free energy of mixing (GM ), activity (a), concentration fluctuation in long wavelength limit [SCC (0)] and chemical short-range order parameter (α 1) of liquid Cu–Pd alloy at 1350?K. The energetic and structural asymmetry of liquid Cu–Pd alloys has been successfully explained on the basis of regular associated solution model. 相似文献
12.
R. R
czka 《Annals of Physics》1985,160(2)
A nonperturbative method of analysis of the stability problem of quantum field theory models is proposed. The method consists in the systematic analysis of the functional dependence on boson field B of the effective boson Lagrangian Seff(B) consisting of the fermion term SlF(B), constraint term SlFP(B) and the boson self-interaction term Sl(B). A new heat kernel representation for SlF(B) is derived in which counterterms are calculated in the explicit functional form by means of the analytic renormalization method. Using these results the instabillity of Yukawa4, four-Fermi4, and the massive Gürsey models is demonstrated. 相似文献
13.
Xinyu Zhang Jiaqian Qin Yanan Xue Shiliang Zhang Qin Jing Mingzhen Ma Riping Liu 《固体物理学:研究快报》2013,7(11):1022-1025
First‐principles density functional calculations are employed to provide a fundamental understanding of the structural features, mechanical properties, deformation behaviours and its electronic origin for the new synthesized FeB4. The calculated elastic moduli suggest that FeB4 has a low compressibility, but results of ideal shear strength and theoretical hardness indicate that FeB4 is a hard material, not a superhard material. We find that the collapse of the unique corrugated B6 units ring in FeB4 under deformation is responsible for the failure under tensile and shear deformation based on the calculated charge density distribution and bonding evolution. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
14.
Quasi-lattice model for the thermodynamic properties and microscopic structure of molten Fe-Si alloy
The quasi-lattice model has been used to study the concentration dependant thermodynamic properties and microscopic structure of Fe-Si alloys in molten state. We have determined the free energy of mixing, excess entropy of mixing, the concentration-concentration structure factor in long wavelength limit [SCC(0)] and the Warren-Cowley short range order parameter (α1) of Fe-Si liquid alloy at 1873 K. The observed asymmetry in the properties of mixing of Fe-Si alloy in molten state is successfully explained on the basis of the quasi-lattice model. The analysis suggests that the Fe2Si complexes are most likely to exist in the liquid state and are strongly interacting in nature. The theoretical analysis suggests that the pairwise interaction energies between the species depend considerably on temperature and the alloy is more ordered towards Fe rich region. 相似文献
15.
W. Andrejtscheff E. Nadjakov Ts. Venkova 《Zeitschrift für Physik A Hadrons and Nuclei》1980,296(2):123-132
The experimental information onB(E2) transition rates in the yrast bands of doubly even nuclei (126≦A≦184) is systematized. The strength functionS exp≡B(E2,I→I?2)×E(I→I?2) is found to reveal characteristic behavior significant for structure studies of yrast bands. The energy-weightedB(E2,I→I?2) values (S exp) and 2?/?2(?: moment of inertia) are plotted versus the rotational frequency squared ?2ω2 for each nucleus. In strongly deformed nuclei (N≧90), theS exp curves smoothly increase for low rotational frequencies suggesting that up to spin valuesI≈8 the ratioQ 0 2 ? is nearly constant (Q 0: quadrupole moment). This is not the case in nuclei with a soft core (N≦88). In the relevant discussion, the hydrodynamical model as well as the CAP effect are considered. The results in the backbending region are qualitatively discussed in terms of the two-band crossing model. Evidence is found supporting the prediction of an oscillating behavior of the yrast-yrare interaction. 相似文献
16.
S. Büttgenbach M. Herschel G. Meisel E. Schrödl W. Witte W. J. Childs 《Zeitschrift für Physik A Hadrons and Nuclei》1974,266(4):271-274
The hyperfine structure of the ground state 4d 5 5s 7 S 3 of95Mo and97Mo has been measured by the atomic beam magnetic resonance technique with the following results:95Mo:A=?208.582060(10)MHz,B=37.050 (100) kHzC=?30 (10) Hz,D=?3 (3) Hz97Mo:A=? 212.980930 (10) MHz,B?69.990(140)kHzC=?5 (10) Hz,D=0 (3) Hz. After application of corrections calculated according to second order perturbation theory, the hyperfine structure constants became:95Mo: Ac=?208.582560(290)MHz,B c =16.920(4300)kHzC c=?30(270) Hz,D c =? 3 (50) Hz97Mo: Ac=212.981450(300) MHz,B c =?90.780(4400)kHzC c=?6(270) Hz,D c =0 (50) Hz. With the known ratio ofg I(95Mo)/g I(97Mo) [1] a calculation of the hyperfine anomaly yields:95 Δ 97=?0.01009(17)%. The ratio of the uncorrectedB factors isB(97Mo)/B(95Mo)=?1.8890(47). Because of the relatively large effects of second order hyperfine structure, the ratio of the correctedBfactors differs considerably from the ratio of the uncorrectedB factors. From the correctedB factors the electric quadrupole moments may be evaluated by means of calculated radial integrals [2]. The results are:Q (95Mo)=?0.019(12)barns,Q(97Mo)=0.102(39)barns. 相似文献