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排序方式: 共有6036条查询结果,搜索用时 31 毫秒
31.
采用一种新的种子层材料:(Ni081Fe019)1-xCrx,通过改变种子层中Cr原子的含量,使得在其上生长的NiFeFeMn双层膜的织构和晶粒尺寸产生极大的差异,系统研究了NiFeFeMn双层膜中FeMn晶粒尺寸和织构对交换偏置的影响.实验结果表明,在FeMn的γ相(111)织构较好的前提下,交换偏置场的大小与织构的差异没有关系;FeMn的晶粒尺寸对交换偏置场有很大影响,较小的反铁磁层晶粒对交换偏置场有利,过大的反铁磁层晶粒不利于交换偏置场.将(Ni081Fe019)05Cr05与传统的种子层材料Ta进
关键词:
交换偏置
晶粒尺寸
织构
种子层 相似文献
32.
Xinjian Yi Sihai Chen Yingrui Wang Bifeng Xiong Hongchen Wang 《International Journal of Infrared and Millimeter Waves》2002,23(12):1699-1704
V02-based thin film materials on silicon substrates are fabricated by ion beam sputtering and a post-annealing which is different from the conventional fabricating method. An infrared linear microbolometer array with 128 pixels is prepared using as-deposited vanadium dioxide thin films. Optical and electrical properties for V02-based microbolometer array are tested. 相似文献
33.
In this paper, we give a new genus-3 topological recursion relation for Gromov-Witten invariants of compact symplectic manifolds.
This formula also applies to intersection numbers on moduli spaces of spin curves. A by-product of the proof of this formula
is a new relation in the tautological ring of the moduli space of 1-pointed genus-3 stable curves.
Research of the first author was partially supported by NSF grant DMS-0204824
Research of the second author was partially supported by NSF grant DMS-0505835 相似文献
34.
简述了聚氧化乙烯介质中的铽、铕、铥、钆、钇、镓、锰掺杂的硫化锌纳米晶的制备方法以及紫外吸收光谱、激发光谱和光激发发射光谱.制成的硫化锌纳米晶直径为3.0~3.5nm. 相似文献
35.
Y. -S. Xiong L. Yi K. -L. Yao Z. -G. Li 《Zeitschrift für Physik B Condensed Matter》1994,96(2):261-265
By means of the generalized static replica symmetric spin glass theory, a quantum HeisenbergS=1/2 spin glass model with the infinite-ranged random Dzyaloshinskii-Moriya (DM) interaction and ferromagnetic coupling is investigated. The dependence of entropy, specific heat, susceptibility and the corresponding order parameters on temperature is studied numerically for different ferromagnetic interactions and fixed anisotropy. Two spin glass phases has been found including transverse and mixed spin glass phases. It has been shown that the local susceptibility exhibits double-cusp features for different ferromagnetic coupling (J
0). Phase transition poins are found in the specific heat-temperature plane at various ferromagnetic coupling values. Additionally, the dependence of the spontaneous moment on temperature is calculated. 相似文献
36.
灰色Verhulst模型的样条插值函数的残差修正 总被引:4,自引:0,他引:4
本用样条函数对灰色Verhulst模型的残差序列进行插值拟合,然后作用于二阶线性微分方程,并以此修正原模型,得到一种新的预测模型的数值解,提高了拟合的精确度。 相似文献
37.
近年来相继从菊花螺属(Siphonaria)海洋软体动物中分离出一系列聚丙酸酯(Polypropi-onate)类化合物.这类化合物在自然界罕见,被认为是菊花螺属软体动物的典型代谢产物.本文实验所用的菊花螺采自福建省湄洲湾莲城半岛.该动物味很苦,有清凉解毒之功. 相似文献
38.
This paper presents the applications of digital image correlation technique to the mesoscopic damage and fracture study of
some granular based composite materials including steelfiber reinforced concrete, sandstone and crystal-polymer composite.
The deformation fields of the composite materials resulted from stress localization were obtained by the correlation computation
of the surface images with loading steps and thus the related damage prediction and fracture parameters were evaluated. The
correlation searching could be performed either directly based on the gray levels of the digital images or from the wavelet
transform (WT) coefficients of the transform spectrum. The latter was developed by the authors and showed higher resolution
and sensitivity to the singularity detection. Because the displacement components came from the rough surfaces of the composite
materials without any coats of gratings or fringes of optical interferometry, both surface profiles and the deformation fields
of the composites were visualized which was helpful to compare each other to analyze the damage of those heterogeneous materials.
The project supported by the National Natural Science Foundation of China (10125211 and 10072002), the Scientific Committee
of Yunnan Province for the Program of Steel Fiber Reinforced Concrete, and the Institute of Chemical Materials, CAEP at Mianyang 相似文献
39.
Wei‐Lie Xiao Jian‐Xin Pu Rui‐Rui Wang Liu‐Meng Yang Xiao‐Li Li Sheng‐Hong Li Rong‐Tao Li Sheng‐Xiong Huang Yong‐Tang Zheng Han‐Dong Sun 《Helvetica chimica acta》2007,90(8):1505-1513
Seven new highly oxygenated nortriterpenoids, rubriflorins D–J ( 1 – 7 ), were isolated from the leaves and stems of Schisandra rubriflora, and their structures were elucidated on the basis of extensive analysis of spectroscopic data. These new compounds feature the opening of ring A compared with related known nortriterpenoids isolated from the genus Schisandra and showed weak activity against HIV‐1. 相似文献
40.
Long-Mei Zeng Xiong Fu Jing-Yu Su Florecita De Guzman J. Francis Schmitz M. Bilayet Hossain Dick van Der Helm 《中国化学》1991,9(2):136-143
Three pyrrololactam alkaloids have been isolated from the marine sponge Phacellia fusca Schmidt collected from the South China Sea, and their structures were determined as 1–3 , on the grounds of spectral data. This is the first report of these compounds from this sponge. The structure of 1 was confirmed by X-ray analysis. 相似文献