B.X. Gu
,
J.R. Zhang
,
B.G. Shen and H Wang (Department of Physics
,
Nanjing University
,
Nanjing 210093
,
China)(State Key Lab. of Magnetism
,
Institute of Physics
,
Chinese Academy of Sciences
,
Beijing 100080
,
China)(Department of Physics
,
Southeastern University
,
Nanjing 210008
,
China)
金属学报(英文版)
The phase component and Curie tempemture of Nd4(Fe1-xCrx)77.5B18.5 (0 0.1. The magnetic measurement shows that Curie temperutures of Fe3B and Nd2Fe14B phases decrease with increasing Cr content. The influence of the substitution of Cr for Fe was discussed.
关键词:
Nd_4(Fe_(1-x)Cr_x)_(77.5)B_(18.5)alloy
,
null
,
null
Z.Wang1)
,
Q.H.Zhao2)
,
D.Z.Liao2)
,
Z.H.Jiang1)
,
S.P.Yana and G.L.Wang1) 1) Department of Chemistry
,
Nankai University
,
Tianjin 300071
,
China. 2) State Key Laboratory Coordination Chemistry
,
Nanjing University
,
Nanjing 210008
,
China
金属学报(英文版)
Five novelcomplexesofformula 〔Ln( pfpr)3〕2 NITRS·nH2 O, where Ln = Nd, Sm , Eu, Gd, Dy; pfpr= pentafluoropropionate; NITRS= 2 - (2’- thienyl) - 4,4 ,5 ,5 te tramethylimidazoline 1 oxyl 3 oxide, and n= 6(for Nd);4(for Eu and Gd) ;2(for Sm and Dy), have been synthesized. Thesecomplexes werecharacterized by elemental analysis, IR, electronicspectra and EPR. Thevariabletemperature(2 300 K) magneticsusceptibility ofthecomplex 〔Gd(pfpr)3〕2 NITRS·4 H2 Owas determined and discussed. Theexchange integral,J= 0 44 cm 1 , wasfoundtobepositive,indicating a weakferromagneticspin ex changeinteraction between theradicaland Gd(III) ion.
关键词:
ferromagnetism
,
null
,
null
,
null
Junming LIU
,
Zhiguo LIU and Zhuangchun WU(National Laboratory of Solid State Microstructures
,
Nanjing University
,
Nanjing
,
210008
,
China)
材料科学技术（英文）
A Monte-Carlo approach of cellular pattern evolution during directional solidification of a binary alloy has been carried out by imposing a non-uniform probability distribution of particle emission from the particle source, as an approach to the contribution of solute redistribution to the interface evolution. Both the bulk and interface diffusion have been involved in the simulation,and coarsening of the cellular patterns with time has been clearly revealed. The remarkable influence of the interface relaxation and the solute redistribution on the profile of solidifying interface has been presented.
关键词:
Guanghou WANG(National Lab. of Solid State Microstructures
,
Nanjing University
,
Nanjing 210093
,
China)Fengqi LIU(Center for Advanced Studies in Science and Technology of Microstructures
,
Nanjing 210093
,
China)
材料科学技术（英文）
We have studied structures and properties of nanostructured films prepared with nanometersized lithium fluoride(LiF) clusters by inert gas condensation method, and then characterized by transmission electron microscope, Fourier transform infrared spectra and Raman scattering spectra, etc. Following important results are obtained: Multi-order-like Raman scatterings from LiF clusters are obtained, including the fine structure of the spectra. The observed Raman peaks are discussed in terms of surface optical modes, Lo. To, LA modes and their combination form.As the cluster size decreases, the phonons are confined in nanoscale so that the q vector selection rule is relaxed or even totally free of q conservation, and prohibition at the first- and third-order scatterings in the bulk LiF crystal is relaxed. The sudece modes appear and play an important role in Raman scattering processes. The infrared absorption spectra are obtained with different deposition conditions. When the clusters are in the medium size range from ～7 to 15 nm, most infrared absorption peaks are second-order feature, and no single surface mode emerges. For the smaller clusters, molecular-like vibration is observed whereas the broad band of long wavelength transverse-optical modes appear from 580 to 400 nm-1 for the clusters larger than 19 nm
关键词:
