共查询到13条相似文献,搜索用时 0 毫秒
1.
Simple analytical recurrent formulae of the branching rules for group chain SU(2N)⊃(SU(N)⊃O(N)⊃O(3))⊗SU(2) are obtained. The highest weight states for the irreducible representations [2alb] or {nS} of group SU(N) and for the irreducible representations (2α1β) or (υS) of group O(N) are constructed respectively 相似文献
2.
In terms of the concept of irreducible tensor basis and the properties of irreducible tensor operator, we give, by mathematical induction, the irreducible representations of O(N) for (m1Nm2N...m[N/2]N) and all reduction factors of O(N)⊃O(N-1) for (1 0...0)⊗(m1Nm2N...m[N/2]N) 相似文献
3.
In this paper, the spinor irreducible representations of O (N) for (σ 1/2 1/2 ± 1/2) with some O (N) U-functions, are obtained by the building-up process. 相似文献
4.
Zhaozhu Yang Huizhao Zhuang Lixia Qin Jinhua Chen Hong Li Dongdong Zhang 《Applied Surface Science》2008,254(13):4166-4170
GaN nanowires and nanorods have been successfully synthesized on Si(1 1 1) substrates by magnetron sputtering through ammoniating Ga2O3/V films at 900 °C in a quartz tube. X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectrum were carried out to characterize the structure, morphology, and photoluminescence properties of GaN sample. The results show that the GaN nanowires and nanorods with pure hexagonal wurtzite structure have good emission properties. The growth direction of nanostructures is perpendicular to the fringes of (1 0 1) plane. The growth mechanism is also briefly discussed. 相似文献
5.
H. R. Zeng K. Shimamura E. A. G. Villora S. Takekawa K. Kitamura J. Y. Xu Q. R. Yin 《固体物理学:研究快报》2007,1(2):R62-R64
Ferroelectric domain structures of (001)‐oriented Pb(Zn1/3Nb2/3)O3–7%PbTiO3 (PZN‐7%PT) single crystals were visualized and characterized by piezoresponse force microscopy (PFM). Locally regular domain configurations are found to be possibly related to the stable macroscopic properties in the PZN‐7%PT single crystals. Nanoscale piezoresponse hysteresis loops measured by PFM tip revealed no evidence of local domain switching behavior in the PZN‐7%PT single crystal. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
6.
S. Neretina R.A. Hughes G.A. Devenyi N.V. Sochinskii P. Mascher 《Applied Surface Science》2009,255(11):5674-5681
The (1 0 0) SrTiO3 substrate has emerged as the oxide substrate of choice for the deposition of a wide variety of materials. The substrate's unavoidable miscut leads to a step-terrace morphology when heated to high temperatures. This morphological transition is accompanied by an atomic scale repositioning of the uppermost terrace atoms, the nature of which is strongly dependent on the substrate temperature and ambient atmosphere used. Here, we report the deposition of CdTe films on the as-received and reconstructed surfaces of (1 0 0) SrTiO3. The as-received substrate gives rise to a [1 1 1] CdTe film with four equally distributed in-plane grain orientations. The surface reconstruction, on the other hand, gives rise to an unprecedented reorientation of the film's grain structure. For this case, a [2 1 1] CdTe film emerges having twelve unevenly distributed in-plane orientations. We attribute the film's grain structure to an atomic scale surface reconstruction, with the anisotropic distribution of grain-types arising from a preferential formation due to the step edges. 相似文献
7.
W. F. Mahmoudi N. Ben Nessib S. Sahal-Bréchot 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,47(1):7-10
Owing to the increasing sensitivity of detectors,
accurate line profiles are needed for accurate stellar
atmospheres modelling and for laboratory and technological plasmas
as well. So, Stark broadening parameters of isolated lines of
complex atoms and ions within the impact and quasistatic
approximation are needed, even if the atomic abundance of the considered element is low.
Angular factors of the diagonal line strength entering the
quadrupole term appearing in the semi-classical expression of the
width of line broadened by electron or ion perturbers, are needed.
The aim of this paper is to extend the previous calculations of
this diagonal multiplet factor which were obtained for
configurations of the type ln and l1
nl2
m to
more complex configurations in LS coupling.
To study the Stark broadening of isolated lines in the impact and
quasistatic approximation, we use the semi-classical-perturbation
treatment, including both dipole and quadrupole contribution in
the expansion of the electrostatic interaction between the optical
electron and the perturber. We also use the Fano-Racah algebra.
Angular factors of the diagonal line strength entering the
quadrupole term appearing in the semi-classical expression of the
width of line broadened by electron or ion perturbers, are
calculated. New diagonal multiplet factor formulae for more
complicated configurations such as
(n1l1
n(LnSn)n2l2
m(LmSm)n3l3
p(LpSp))
are provided.
These formulae can enter the computer Stark semi-classical
perturbation codes. 相似文献
8.
C. Chen B. C. Gou 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(3):545-550
The hyperfine structure parameters of the 1s22snp (n=2, 3) 3P states for the beryllium isoelectronic sequence from Z= 4 to 10 are calculated with the full-core plus correlation (FCPC)
wave functions. For the 1s22s2p 3P state of the beryllium atom, the calculated fine structure parameters are in good agreement with the latest theoretical
and experimental data in the literature. It is shown that hyperfine constants of the low-lying excited states for the beryllium
atom can be calculated accurately using this theoretical method. For 1s22snp (n=2, 3) 3P states of the beryllium isoelectronic sequence, our predictions may provide valuable reference data for other theoretical
calculations and experimental measurements in future. 相似文献
9.
The spin flop behaviour of low anisotropy Mn ions within the mixed halide (54Mn)Mn(Br
x
Cl1−x
)2·4H2O is shown to be interpolative with that of the two terminal compounds, in striking contrast with the dynamics of nuclear
spin lattice relaxation. 相似文献
10.
I. Sakho A. S. Ndao M. Biaye A. Wague 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,47(1):37-44
Screening Constant by Unit Nuclear Charge (SCUNC) is a new analytical method
suitable for the treatment of the properties of He-like systems. In this
paper, the possibilities of the method are demonstrated for calculating in
the framework of semi-empirical procedure, total energies, total
electron-electron interaction energies and excitation energies for
(ns2)1Se, (np2)1De and (Nsnp)1P° doubly
excited states of He-like ions. The proposed semi-empirical scheme,
leads to accurate results in good agreement as well as with available other
theoretical results than experimental data. 相似文献
11.
Facile Synthesis of Gd(OH)3‐Doped Fe3O4 Nanoparticles for Dual‐Mode T1‐ and T2‐Weighted Magnetic Resonance Imaging Applications 下载免费PDF全文
Hongdong Cai Xiao An Shihui Wen Jingchao Li Guixiang Zhang Xiangyang Shi Mingwu Shen 《Particle & Particle Systems Characterization》2015,32(10):934-943
The facile hydrothermal synthesis of polyethyleneimine (PEI)‐coated iron oxide (Fe3O4) nanoparticles (NPs) doped with Gd(OH)3 (Fe3O4‐Gd(OH)3‐PEI NPs) for dual mode T1‐ and T2‐weighted magnetic resonance (MR) imaging applications is reported. In this approach, Fe3O4‐Gd(OH)3‐PEI NPs are synthesized via a hydrothermal method in the presence of branched PEI and Gd(III) ions. The PEI coating onto the particle surfaces enables further modification of poly(ethylene glycol) (PEG) in order to render the particles with good water dispersibility and improved biocompatibility. The formed Fe3O4‐Gd(OH)3‐PEI‐PEG NPs have a Gd/Fe molar ratio of 0.25:1 and a mean particle size of 14.4 nm and display a relatively high r2 (151.37 × 10?3m ?1 s?1) and r1 (5.63 × 10?3m ?1 s?1) relaxivity, affording their uses as a unique contrast agent for T1‐ and T2‐weighted MR imaging of rat livers after mesenteric vein injection of the particles and the mouse liver after intravenous injection of the particles, respectively. The developed Fe3O4‐Gd(OH)3‐PEI‐PEG NPs may hold great promise to be used as a contrast agent for dual mode T1‐ and T2‐weighted self‐confirmation MR imaging of different biological systems. 相似文献
12.
Iron Oxide Nanoparticles: Facile Synthesis of Gd(OH)3‐Doped Fe3O4 Nanoparticles for Dual‐Mode T1‐ and T2‐Weighted Magnetic Resonance Imaging Applications (Part. Part. Syst. Charact. 10/2015) 下载免费PDF全文
Hongdong Cai Xiao An Shihui Wen Jingchao Li Guixiang Zhang Xiangyang Shi Mingwu Shen 《Particle & Particle Systems Characterization》2015,32(10):918-918
13.
The cross-sections for formation of isomeric pair, 75Gem(σm) and 75Geg(σg), through 76Ge(n, 2n), 75As(n, p) and 78Se(n, α) reactions were measured at 13.73 MeV, 14.42 MeV and 14.77 MeV neutrons and also estimated using EMPIRE-II and TALYS codes over neutron energies from near threshold to 20 MeV. For each (n, 2n), (n, p) and (n, α) reaction, the cross-section initially increases with neutron energy, but starts decreasing as the neutron energy exceeds the respective threshold of (n, 3n), (n, pn) and (n, αn) reactions. The higher values of σm relative to σg reveal that the transitions of the excited 75Ge from higher energy levels to metastable state (7+/2) are favored as compared to unstable ground state (1−/2). The present values of cross sections for formation of 75Gem,g through (n, 2n) and (n, α) reactions are lower, and that of (n, p) reaction are higher compared to most of the corresponding literature cross-sections. 相似文献