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排序方式: 共有164条查询结果,搜索用时 296 毫秒
1.
Substituting Al for Fe in Pr(Al_xFe_(1-x))_(1.9) alloys:Effects on magnetic and magnetostrictive properties 下载免费PDF全文
The magnetostrictive effects of substituting Al for Fe in Pr(AlxFe1-x)1.9(x = 0.0, 0.02, 0.05, 0.10) alloys between5 K and 300 K were investigated. The substitution decreases the Curie temperature and the value of λ111. Fortunately, the substitution slightly increases the magnetostriction in a low magnetic field, which imbues these materials with potential advantages for applications. Rotation of the easy magnetization direction(EMD) from [111] to [100] in the Pr(Al0.02Fe0.98)1.9alloy as temperature decreases was detected by step scanned XRD reflections. 相似文献
2.
Controllable synthesis,characterization,and growth mechanism of hollow Zn_x Cd_(1-x) S spheres generated by a one-step thermal evaporation method 下载免费PDF全文
Novel hollow ZnxCdl xS spheres that are uniform in size are synthesized through the one-step thermal evaporation of a mixture of Zn and CdS powder. From an X-ray diffraction (XRD) study, the hexagonal wurtzite phase of ZnxCdl_xS is verified, and the Zn mole fraction (x) is determined to be 0.09. According to the experimental results, we propose a mechanism for the growth of Zn0.09Cd0.91S hollow spheres. The results of the cathodoluminescence investigation indicate uniform Zn, Cd, and S distribution of alloyed Zn0.09Cd0.91S, instead of separate CdS, ZnS, or nanocrystals of a core- shell structure. To the best of our knowledge, the fabrication of ZnxCd1-xS hollow spheres of this kind by one-step thermal evaporation has never been reported. This work would present a new method of growing and applying hollow spheres on Si substrates, and the discovery of the Zn0.09Cd0.91S hollow spheres would make the investigation of ZnxCd1-xS micro/nanostructures more interesting and intriguing. 相似文献
3.
乞借贵刊一角,以对石墨烯、富勒烯的译名提出异意,愿与物理学界、化学界、材料科学界学者们切磋之.
Graphene名词因发明者A.Geim和K.Novoselov获2010年诺贝尔物理奖而享誉环球.从物理学观点来看,它仅仅是单层或少层石墨片,或者可表述为纯碳原子所构成的石墨单层结构的二维薄膜.它具有特殊的无能隙能带结构, 相似文献
4.
纳米材料是指三维空间尺度中至少有一维处于纳米量级的材料,通常为1—100nm,如纳米微粒,纳米线、管,纳米薄膜或其组合材料,近年来纳米材料中的巨磁电阻效应颇受人们青睐,本文将重点介绍颗粒膜,颗粒合金薄带,非连续多层膜,颗粒—薄膜混合型膜以及磁性隧道结的巨磁电阻效应。 相似文献
6.
Dy substitution effect on the temperature dependences of magnetostriction in Pr_(1-x)Dy_xFe_(1.9) alloys 下载免费PDF全文
The temperature dependences of magnetostriction in Pr_(1 x)Dy_xFe_(1.9)(0 ≤ x ≤ 1.0) alloys between 5 K and 300 K were investigated.An unusual decrease of magnetostriction with temperature decreasing was found in Pr-rich alloys(0 ≤x≤ 0.2),due to the change of the easy magnetization direction(EMD).Dy substitution reduces the magnetostriction in high-magnetic field(10 kOe ≤ H≤90 kOe) at 5 K,while a small amount of Dy substitution(x = 0.05) is beneficial to increasing the magnetostriction in low-magnetic field between 10 K and 50 K.This makes the alloys a potential candidate for low temperature applications. 相似文献
7.
Effect of Cu doping on the magnetic and electrical properties of n=2 Ruddlesden-Popper manganates 下载免费PDF全文
A series of polycrystalline Cu-doped n=2 Ruddlesden-Popper manganates La1.2Sr1.8CuzMn(2-x)O7 (x=0, 0.04, 0.13) were synthesized by the solid state reaction method. The effect of Cu doping on the magnetic and transport properties has been studied. It is found that Cu substitution for Mn greatly affects the magnetic and electrical properties of the parent phase La1.2Sr1.8Mn2O7. With the increase of Cu content, the system undergoes a transition from longrange ferromagnetic order to the spin glass state and further to an antiferromagnetic order. A little of Cu dopant can lead to the samples showing semiconductor or insulator behaviour in the whole observed temperature range while the parent phase has a metal-insulator transition. These samples show colossal magnetoresistance at low temperatures and the value of it decreases with increasing Cu content. 相似文献
8.
采用固相反应法,制备了不同成分的稀释磁性半导体Sn1-xMnxO 2(x=002,004,006).利用x射线衍射和傅里叶变换红外光谱法证明 了锰均匀地掺杂到二氧化锡中.在室温下研究了掺锰二氧化锡基稀释半导体的磁性,发现它具有明显的铁磁性 ,同时对磁性的强弱与锰的含量和烧结温度的关系作了研究.
关键词:
稀释磁性半导体
掺杂
烧结
铁磁性
1-xMnx O2')" href="#">Sn1-xMnx O2 相似文献
9.