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N.D. Tho N. Chau S.C. Yu H.B. Lee N.D. The L.A. Tuan 《Journal of magnetism and magnetic materials》2006
Effect of annealing on the soft magnetic properties of Fe73.5Si13.5B9Nb3Au1 amorphous ribbon has been investigated by means of structure examination, magnetoimpedance ratio (MIR) and incremental permeability ratio (PR) spectra measured in the frequency range of 1–10 MHz at a fixed current of 10 mA X-ray diffraction analysis showed that the as-cast sample was amorphous and it became nanocrystalline under a proper heat treatment. When annealing amorphous alloy at 530 °C for 30, 60, 90 min, soft magnetic properties have been improved drastically. Among the samples investigated, the sample annealed at 530 °C for 90 min showed the softest magnetic behavior. The MIR and PR curves revealed the desirable changes in anisotropy field depending upon annealing. 相似文献
4.
5.
The ALEPH Collaboration A. Heister et al. 《The European Physical Journal C - Particles and Fields》2003,29(2):143-170
An improved search for B
s
0 oscillations is performed in the ALEPH data sample collected during the first phase of LEP, and reprocessed in 1998. Three
analyses based on complementary event selections are presented. First, decays of B
s
0 mesons into hadronic flavour eigenstates are fully reconstructed. This selection yields a small sample of candidates with
excellent decay length and momentum resolution and hi gh average B
s
0 purity. Semileptonic decays with a reconstructed
D
s
- meson provide a second sample with larger statistics, high average
B
s
0 purity, but a poorer momentum and decay length resolution due to the partial decay reconstruction. Finally, semileptonic
b-hadron decays are inclusively selected and yield the data sample with the highest sensitivity to B
s
0 oscillations, as the much higher statistics compensate for the low average B
s
0 purity and poorer time resolution. A lower limit is set atps-1 at 95% C.L., significantly lower than the expected limit of 15.2 ps-1.
Received: 21 February 2003 / Published online: 11 June 2003 相似文献
6.
The Ze-Ro Zeuthen-Roma Collaboration 《The European Physical Journal A - Hadrons and Nuclei》2003,17(3):365-368
The accuracy of structure functions computations on the lattice may become comparable to experimental determinations. We discuss the strategy followed by the Ze-Ro Collaboration that allows the reconstruction of the running of the leading-twist non-singlet operator in the continuum and fully non-perturbatively renormalized.Received: 1 November 2002, Published online: 15 July 2003PACS:
11.15.Ha Lattice gauge theory - 12.38.Gc Lattice QCD calculations 相似文献
7.
The Jefferson Laboratory E- Collaboration 《The European Physical Journal A - Hadrons and Nuclei》2003,18(2-3):181-183
The ratio G
e
n
/G
m
n
of the electric to the magnetic form factor of the neutron has been measured by analyzing the polarization of the recoiling neutron in quasi-elastic scattering of longitudinally polarized electrons from deuterium at the Q
2 values of 0.45, 1.15, and 1.47 (GeV/c)2. The experiment has been performed in Hall C of the Thomas Jefferson National Accelerator Facility. With G
m
n
being known G
e
n
can be deduced. The preliminary results show that the lowest Q
2 points follow the Galster parametrization and that the 1.47 (GeV/c)2 point rises above this parametrization.Received: 30 September 2002, Published online: 22 October 2003PACS:
13.40.Gp Electromagnetic form factors - 14.20.Dh Protons and neutrons - 24.70. + s Polarization phenomena in reactions 相似文献
8.
Hoang The Ban Kei Nishii Yasuo Tsunogae Takeshi Shiono 《Journal of polymer science. Part A, Polymer chemistry》2007,45(13):2765-2773
This article reports a synthetic method for a norbornene–ethylene–styrene (N‐E‐S) terpolymer, which has not been well investigated so far, via incorporation of styrene (S) into vinyl‐type norbornene–ethylene (N‐E) copolymers catalyzed by a substituted ansa‐fluorenylamidodimethyltitanium [Me2Si(3,6‐tBu2Flu)(tBuN)]TiMe2 catalyst ( I ) activated with a [Ph3C][B(C6F5)4]/Al(iBu)3 cocatalyst at room temperature in toluene. The resulting terpolymerization product contained the targeted N‐E‐S terpolymer and the contaminated homopolymers, which were then able to be completely removed by solvent fractionation techniques. While homopolystyrene was easily extracted by fractionation with methylethylketone as a soluble part, homopolyethylene and a trace amount of homopolynorbornene could be perfectly separated by fractionation with chloroform as insoluble parts. The detail characterizations of a chloroform‐soluble polymer with gel permeation chromatography, nuclear magnetic resonance, and differential scanning calorimetry analyses proved that it contained a true N‐E‐S terpolymer with long N‐E sequences incorporated with isolated or short styrene sequences. The homogeneity of the morphology together with a single glass transition temperature that proportionally decreased with the increase of the styrene contents indicated that the N‐E‐S terpolymer obtained in this work is a random polymer with an amorphous structure. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2765–2773, 2007 相似文献
9.
一种新型有机电致微腔结构的双模发射 总被引:4,自引:4,他引:0
采用结构Glass/DBR/ITO/NPB/NPB:Alq/Alq/Al制作了有机微腔电致发光器件。将空穴传输材料与发光材料以一定比例混合作为发光层,为了便于对比,在不改变有机层的膜厚的情况下同时制作了传统的异质结微腔器件,发现两种器件的发光光谱有很大不同,器件的复合效率与传统的异质结器件相比也得到了很大提高,这是因为将两种有机材料混合能消除界面势垒,提高器件的复合效率,从而提高了器件的发光性能,实现了微腔双模发射,且两个模式的半峰全宽分别为8nm和12nm。通过进一步优化器件结构可以实现微腔白光发射。 相似文献
10.
研究了酚醛型吸附树脂在水体系中对吡啶和N,N-二甲基苯胺的静态和动态吸附行为.结果表明,在水中树脂对吡啶和N,N-二甲基苯胺的吸附主要以疏水吸附机理进行;吸附吡啶和N.N-二甲基苯胺的初始阶段,即达到38.3~48.9%平衡吸附时,吸附速率数据和半经验速率方程很吻合:酚醛型吸附树脂等温吸附吡啶和N,N-二甲基苯胺的平衡吸附数据符合Langmuir方程,相关系数在0.99以上,酚醛型吸附树脂吸附吡啶和N,N-二甲基苯胺属单分子层吸附:用80%的乙醇溶液作洗脱剂来洗脱吸附吡啶已达饱和的JDW-2树脂,效果是很理想的.在3.6个床体积内洗脱率达91.52%,4.8个床体积内洗脱率达到94.85%。表明酚醛型吸附树脂具有优良的洗脱性能. 相似文献