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LIU Yihua,YANG Linqian Shandong University,Jinan LIU Yihua,associate professor,

金属学报 , 1989,
Abstract: The amorphous CoZr soft magnetic films with superior properties wereprepared by radio-frequency sputtering under pressure of 0.5 Pa Ar. The saturationmagnetization of the amorphous CoZr film with relation to the Zr content andtemperature was investigated. The amorphous CoZr films composed of differentconstituents obey the Bloch T~(3/2)-law in a wide range of temperatures. The numberof electrons transferred from each Zr atom to 3d energy band of Co calculatedby the rigid band model is about 2.27.
Contraction and expansion effects on the substitution-defect properties of thirteen alloying elements in bcc Fe  [PDF]
Wei Liu,Wei-Lu Wang,C. S. Liu,Q. F. Fang,Qun-Ying Huang,Yi-Can Wu,Key Laboratory of Materials Physics,Institute of Solid State Physics,Chinese Academy of Sciences,P. O. Box 1129,Hefei 230031,P. R. China,Institute of Plasma Physics,Chinese Academy of Sciences,Hefei 230031,P. R. China
Physics , 2010,
Abstract: Proposed as blanket structural materials for fusion power reactors, reduced activation ferritic/martensitic (RAFM) steel undergoes volume expanding and contracting in a cyclic mode under service environment. Particularly, being subjected to significant fluxes of fusion neutrons RAFM steel suffers considerable local volume variations in the radiation damage involved regions. It is necessary to study the structure properties of the alloying elements in contraction and expansion states. In this paper we studied local substitution structures of thirteen alloying elements Al, Co, Cr, Cu, Mn, Mo, Nb, Ni, Si, Ta, Ti, V, and W in bcc Fe and calculated their substitutional energies in the volume variation range from -1.0% to 1.0%. From the structure relaxation results of the first five neighbor shells around the substitutional atom we find the relaxation in each neighbor shell keeps approximately uniform within the volume variation from -1.0% to 1.0% except those of Mn and the relaxation of the fifth neighbor shell is stronger than that of the third and forth, indicating that the lattice distortion due to the substitution atom is easier to spread in <111> direction than in other direction. The relaxation pattern and intensity are related to the size and electron structure of the substitutional atom. For some alloying elements, such as Mo, Nb, Ni, Ta, Ti and W, the substitutional energy decreases noticeably when the volume increases. Further analysis show that the substitutional energy comprises the energy variation originated from local structure relaxation and the chemical potential difference of the substitutional atom between its elemental crystalline state and the solid solution phase in bcc Fe. We think the approximately uniform relaxation of each neighbor shell around a substitutional atom give rise to a linear decrease in the substitutional energy with the increasing volume.
LIU Yihua Shandong University,Jinan,ChinaYA NG Linqian Huaqiao University,Quanzhou,Fujian,China LIU Yihua Associate Professor,Deptof Physics,Shandong University,Jinan,China,
LIU Yihua Shandong University
,Jinan,China YA NG Linqian Huaqiao University,Quanzhou,Fujian,China LIU Yihua Associate Professor,Dept.of Physics,Shandong University,Jinan,China

金属学报(英文版) , 1990,
Abstract: The amorphous CoZr soft magnetic films with superior properties were prepared by radio-frequency sputtering under pressure of 0.5Pa Ar.The saturation magnetization of the amorphous CoZr films with relation to the Zr content and temperature was investigated.The amorphous CoZr films composed of different constituents obey the Bloch T~(3/2)-low in a wide range of temperatures.The number of electrons transferred from each Zr atom to 3d energy band of Co calculated by the rigid band model is about 2.27.
Stochastic sandwich method with low mode substitution for nucleon isovector matrix elements  [PDF]
Yi-Bo Yang,Andrei Alexandru,Terrence Draper,Ming Gong,Keh-Fei Liu
Physics , 2015,
Abstract: We introduce a stochastic sandwich method with low-mode substitution to evaluate the connected three-point functions. The isovector matrix elements of the nucleon for the axial-vector coupling $g_A^3$, scalar couplings $g_S^3$ and the quark momentum fraction $\langle x\rangle_{u -d}$ are calculated with overlap fermion on 2+1 flavor domain-wall configurations on a $24^3 \times 64$ lattice at $m_{\pi} = 330$ MeV with lattice spacing $a = 0.114$ fm.
非晶态CoZr软磁薄膜的磁性  [PDF]
金属学报 , 1989,
Abstract: 用射频溅射法制备了非晶态CoZr合金薄膜,在0.5Pa的氩气压下,可以得到性能优良的软磁薄膜。研究了非晶态CoZr膜的饱和磁化强度与Zr含量及温度的关系,发现对各种成分的非晶态CoZr膜,在很宽的温度范围内都可满足BlochT~(3/2)定律。根据刚带模型计算出每个Zr原子向Co的3d能带转移的电荷数约为2.27。
Formulation of the Equilibrium Equations of Transversely Loaded Elements taking Shear Deformation into Consideration
Onyeyili I. O.,Okonkwo V. O.
International Journal of Engineering Science and Technology , 2012,
Abstract: In this work a mathematical model for the consideration of deformation due to shearing forces in structural analysis was formulated. The stiffness matrix for a prismatic element taking shear deformation into account was developed. The force/load vectors for various cases of transversely loaded elements taking shear deformationinto consideration were also formulated and these were presented in tables synonymous to the tables of ‘end forces due to unit end displacements’ and ‘fixed end moments on transversely loaded elements’ found in many structural analysis textbooks. These tables will enable an easy implementation of the effects of deformation dueto shear forces in structural analysis when using the stiffness method.
γ-MYN: a new algorithm for estimating Ka and Ks with consideration of variable substitution rates
Da-Peng Wang, Hao-Lei Wan, Song Zhang, Jun Yu
Biology Direct , 2009, DOI: 10.1186/1745-6150-4-20
Abstract: We incorporated a new feature for analyzing evolving DNA sequences–unequal substitution rates among different sites–into MYN method, and proposed a modified version, namely γ (gamma)-MYN, based on an assumption that the evolutionary rate at each site follows a mode of γ-distribution. We applied γ-MYN to analyze the key estimator of selective pressure ω (Ka/Ks) and other relevant parameters in comparison to two other related methods, YN and MYN, and found that neglecting the variation of substitution rates among different sites may lead to biased estimations of ω. Our new method appears to have minimal deviations when relevant parameters vary within normal ranges defined by empirical data.Our results indicate that unequal substitution rates among different sites have variable influences on ω under different evolutionary rates while both transition/transversion rate ratio and unequal nucleotide frequencies affect Ka and Ks thus selective pressure ω.This paper was reviewed by Kateryna Makova, David A. Liberles (nominated by David H Ardell), Zhaolei Zhang (nominated by Mark Gerstein), and Shamil Sunyaev.Comparative sequence analysis is a powerful tool for biologists to study evolutionary relationship among animals and plants across diverse taxonomic lineages [1-3]. Pair-wise sequence comparison is perhaps the simplest comparative analysis for phylogeny for two reasons [4]. First, calculating pair-wise distances is the initial step for distance-matrix methods of phylogeny reconstruction. Second, Markov-process models of nucleotide substitution used in distance calculations lay a foundation for likelihood and Bayesian analyses. One of the sophisticated methods is to estimate nonsynonymous and synonymous substitution rates for interrogating sequence dynamics and constructing phylogenetic trees. Since Ka and Ks represent the number of substitutions per nonsynonymous and synonymous site, respectively, these parameters (or often their ratio Ka/Ks or ω) are important for the e
Effect of yoga relaxation techniques on performance of digit-letter substitution task by teenagers  [cached]
Pradhan Balaram,Nagendra H
International Journal of Yoga , 2009,
Abstract: Background/Aims : Memory and selective attention are important skills for academic and professional performance. Techniques to improve these skills are not taught either in education or company training courses. Any system which can systematically improve these skills will be of value in schools, universities, and workplaces. Aims:To investigate possible improvements in memory and selective attention, as measured by the Digit-Letter Substitution Task (DLST), due to practice of Cyclic Meditation (CM), a yoga relaxation technique, as compared to Supine Rest (SR). Materials and Methods : Subjects consisted of 253 school students, 156 boys, 97 girls, in the age range 13-16 years, who were attending a 10-day yoga training course during summer vacation. The selected subjects had English as their medium of instruction in school and they acted as their own controls. They were allocated to two groups, and tested on the DLST, immediately before and after 22.5 minutes practice of CM on one day, and immediately before and after an equal period of SR on the other day. The first group performed CM on day 9 and SR on day 10. For the second group, the order was reversed. Results : Within each group pre-post test differences were significant for both the relaxation techniques. The magnitude of net score improvement was greater after SR (7.85%) compared to CM (3.95%). Significance levels were P < 0.4 x 10 -9 for SR and P < 0.1 x 10 -3 for CM. The number of wrong attempts also increased significantly on both interventions, even after removing two outlier data points on day 1 in the SR group. Conclusions: Both CM and SR lead to improvement in performance on the DLST. However, these relaxation techniques lead to more wrong cancellation errors.
NMR Characterization of Sulphur Substitution Effects in the K(x)Fe(2-y)Se(2-z)S(z) high Tc Superconductor  [PDF]
D. A. Torchetti,T. Imai,H. C. Lei,C. Petrovic
Physics , 2011, DOI: 10.1103/PhysRevB.85.144516
Abstract: We present an NMR study of the effect of S substitution in the high Tc superconductor K(x)Fe(2-y)Se(2-z)S(z) in a temperature range up to 250 K. We present NMR Knight shift and nuclear spin-lattice relaxation rate 1/T1 data, and compare our results to that of the non-substituted system K(x)Fe(2-y)Se(2).
19F nuclear spin relaxation and spin diffusion effects in the single ion magnet LiYF4:Ho3+  [PDF]
B. Z. Malkin,M. V. Vanyunin,M. J. Graf,J. Lago,F. Borsa,A. Lascialfari,A. M. Tkachuk,B. Barbara
Physics , 2008, DOI: 10.1140/epjb/e2008-00411-7
Abstract: Temperature and magnetic field dependences of the 19F nuclear spin-lattice relaxation in a single crystal of LiYF4 doped with holmium are described by an approach based on a detailed consideration of the magnetic dipole-dipole interactions between nuclei and impurity paramagnetic ions and nuclear spin diffusion processes. The observed non-exponential long time recovery of the nuclear magnetization after saturation at intermediate temperatures is in agreement with predictions of the spin-diffusion theory in a case of the diffusion limited relaxation. At avoided level crossings in the spectrum of electron-nuclear states of the Ho3+ ion, rates of nuclear spin-lattice relaxation increase due to quasi-resonant energy exchange between nuclei and paramagnetic ions, in contrast to the predominant role played by electronic cross-relaxation processes in the low-frequency ac-susceptibility.
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