全文获取类型
收费全文 | 69篇 |
免费 | 1篇 |
国内免费 | 6篇 |
专业分类
化学 | 18篇 |
力学 | 13篇 |
数学 | 11篇 |
物理学 | 34篇 |
出版年
2021年 | 3篇 |
2020年 | 2篇 |
2019年 | 4篇 |
2018年 | 1篇 |
2017年 | 2篇 |
2016年 | 5篇 |
2015年 | 1篇 |
2014年 | 2篇 |
2013年 | 3篇 |
2012年 | 6篇 |
2011年 | 6篇 |
2010年 | 5篇 |
2009年 | 2篇 |
2008年 | 2篇 |
2007年 | 1篇 |
2006年 | 1篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 5篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1999年 | 5篇 |
1998年 | 2篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1989年 | 1篇 |
排序方式: 共有76条查询结果,搜索用时 62 毫秒
1.
2.
Liqing Liu Kunquan Hong Xing Ge Mingxiang Xu 《Applied Physics A: Materials Science & Processing》2014,115(4):1147-1150
Copper oxide (CuO) is a p-type semiconductor with a band gap of 1.2 eV, which is well known in high-temperature superconductor and antiferromagnetic (AFM) materials through Cu–O–Cu super-exchange interaction. In this paper, we report the strong anisotropic ferromagnetism (FM) in aligned CuO nanorod arrays synthesized by a microwave-assisted hydrothermal method. The transmission electron microscopy (TEM) image shows that the CuO nanorod consists of a large number of smaller nanorods with almost the same growth direction. The X-ray diffraction (XRD) pattern indicates that the CuO nanorods are well crystallized with highly preferred orientation of the [020] direction. These CuO nanorod arrays show room-temperature ferromagnetism, with strong magnetic anisotropy when the magnetic field is applied perpendicular or parallel to the rod axis. This phenomenon of room-temperature ferromagnetism in those aligned CuO nanorods might originate from uncompensated surface spins and shape anisotropy of the nanorods. 相似文献
3.
4.
Y.?Manzhur P. M.?Imielski K.?Potzger W. D.?Brewer M.?Dietrich M. J.?PrandoliniEmail author H. H.?Bertschat 《The European Physical Journal B - Condensed Matter and Complex Systems》2005,46(4):535-540
The induced magnetism of isolated (Cd) adatoms,
soft-landed onto ultrathin Ni layers grown pseudo-morphologically
on Pd(001) (aPd = 3.8907 Å), was studied using the
perturbed angular correlation (PAC) technique. The magnitude of
the induced magnetic response (magnetic hyperfine field of
|5.2| T) was found to be ca. 30% smaller than on bulk Ni
(aNi = 3.524 Å) surfaces. This result is compared to ab initio calculations. Additionally, the magnetic anisotropy of
the induced response was found to be modified as compared to bulk
Ni surfaces and the induced hyperfine field was observed to emerge
from the plane at an angle of 50(5)○ to the surface
normal. This canted magnetic anisotropy is attributed to the large
lattice expansion of the ultrathin Ni film on Pd(001). 相似文献
5.
随着热电制冷器(Thermoelectric cooler,TEC)的广泛应用,TEC过冷特性受到重视.与稳态制冷相比,当给TEC施加脉冲电流时,其将出现过冷效应,从而得到比稳态工作时更低的温度.然而,过冷效应往往伴随着温度的过冲.特别地,当TEC应用于芯片温度控制时,较大的温度过冲将会影响芯片的使用寿命.目前,抑制过冷特性中温度过冲的方式主要采用在电流施加脉冲的同时,对冷端冷却负荷QC和对流换热系数h也进行相应的改变.本文即在此基础上,将TEC的电流脉冲形状的变化和所施加脉冲的QC和h相结合对TEC的过冷特性进行了优化,以减小TEC过冷温度的过冲.对比已有的实验结果,有限元仿真表明,本文所提出的优化方案比采用单一形式的参量控制,可以有效降低过冷特性时的温度过冲10 K左右,具有良好的应用前景. 相似文献
6.
Qingyu Xu Zheng WenJinlong Gao Di WuShaolong Tang Mingxiang Xu 《Physica B: Condensed Matter》2011,406(10):2025-2027
Bi(Fe0.95Co0.05)O3 films were prepared on conductive indium tin oxide (ITO)/glass substrates by chemical solution deposition. Well saturated polarization hysteresis loop has been observed with a remnant polarization value of about 22 μC/cm2 at room temperature. Weak ferromagnetism with saturation magnetization of about 3 emu/cm3 was observed at room temperature. The clear observation of both room temperature ferroelectric and ferromagnetic properties suggests the potential multiferroic applications of Bi(Fe0.95Co0.05)O3. 相似文献
7.
8.
Mingxiang Chen Dominic P. Clemence 《Journal of Difference Equations and Applications》2013,19(9):887-899
This paper considers a non-linear system of ordinary differential equations, which arises in the study of hantavirus epidemics. The system has the property that the total population obeys the logistic equation. For this system, we use linearization and the dynamical properties of the logistic equation to analyze the dynamics of the subpopulation system. In view of the usual numerical instabilities associated with standard finite difference methods used for simulating such systems, we construct non-standard finite difference (NSFD) schemes, which preserve the dynamic properties of the system, and may therefore be used for its simulation. 相似文献
9.
Mingxiang Chen Dominic P. Clemence 《Journal of Difference Equations and Applications》2013,19(12):1243-1256
This paper studies the stability properties of a nonstandard finite difference (NSFD) scheme used to simulate the dynamics of a mouse population model in hantavirus epidemics. It is shown that this difference scheme and the underlying system of differential equations have the same dynamics. The proof uses the fact that the total population obeys the logistic equation, as well as techniques from calculus, graphical analysis, and dynamical systems. 相似文献
10.
Zhenjiang Qiu Mingxiang Zhu Lu Zheng Jingya Li Dapeng Zou Yangjie Wu Yusheng Wu 《Tetrahedron letters》2019,60(19):1321-1324
An efficient protocol for the synthesis of α-benzyl azetidines starting from benzylboronic acid pinacol ester derivatives and 3-iodoazetidine was developed. A wide range of α-benzyl azetidine derivatives were obtained in moderate to good yields with high regioselectivity (>99%). 相似文献