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Spanwise phase transition between pure modes A and B in a circular cylinder’s wake. Part II: spatiotemporal evolution of vorticity 期刊论文 OAI收割
Fluid Dynamics Research, 2023, 卷号: 55, 期号: 5
作者: Lin,L M; Lin LM(林黎明)

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spanwise phase transition wake circular cylinder mode A mode B

Phase transition between pure modes A and B in a circular cylinder's wake. Part I: analysis of fluid forces 期刊论文 OAI收割
FLUID DYNAMICS RESEARCH, 2023, 卷号: 55, 期号: 3, 页码: 35502
作者: Lin LM(林黎明)

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收藏 | 浏览/下载：22/0 | 提交时间：2023/07/17

phase transition wake circular cylinder mode A mode B

The braking index of PSR B0540-69 and the associated pulsar wind nebula emission after spin-down rate transition 期刊论文 OAI收割
Monthly Notices of the Royal Astronomical Society, 2020, 卷号: 494, 页码: 1865-1870
作者: HXMT

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收藏 | 浏览/下载：59/0 | 提交时间：2022/02/08

stars: magnetic field stars: neutron pulsars: general Astrophysics - High Energy Astrophysical Phenomena Abstract: In 2011 December, PSR B054-69 experienced a spin-down rate transition (SRT), after which the spin-down power of the pulsar increased by $\sim 36{{\ \rm per\ cent}}$. About 1000 d after the SRT, the X-ray luminosity of the associated pulsar wind nebula (PWN) was found to brighten by $32\pm 8{{\ \rm per\ cent}}$. After the SRT, the braking index n of PSR B0540-69 changes from n = 2.12 to 0.03 and then keeps this value for about five years before rising to n = 0.9 in the following years. We find that most of the current models have difficulties in explaining the measured braking index. One exceptive model of the braking index evolution is the increasing dipole magnetic field of PSR B0540-69. We suggest that the field increase may result from some instabilities within the pulsar core that enhance the poloidal component at the price of toroidal component of the magnetic field. The increasing dipole magnetic field will result in the X-ray brightening of the PWN. We fit the PWN X-ray light curve by two models: one assumes a constant magnetic field within the PWN during the brightening and the other assumes an enhanced magnetic field proportional to the energy density of the PWN. It appears that the two models fit the data well, though the later model seems to fit the data a bit better. This provides marginal observational evidence that magnetic field in the PWN is generated by the termination shock. Future high-quality and high-cadence data are required to draw a solid conclusion.

Synthesis, characterization, and ethylene polymerization behaviors of late-transition metal complexes coordinated with chlorinated bis(arylimino)pyridine ligand 期刊论文 OAI收割
polymer, 2014, 卷号: 55, 期号: 18, 页码: 4611-4618
Liu, Heng; Wang, Feng; Liu, Li; Jai,Xiang-Yu; Zheng,Wenjie; Guo,Jun; Zhang,Chun-Yu; Bai,Chen-Xi; Hu,Yan-Ming; Zhang,Xue-Quan

收藏 | 浏览/下载：34/0 | 提交时间：2015/10/20

A series of late-transition metal complexes supported with chlorinated bis(arylimino)pyridine ligands [2 Ar = 2 Ar = 2 Ar = 2 Ar = 4-Cl-2 Ar = 4-Br-2 6-(ArN=CCl)(2)C5H3N]MtCl(2) (Ar = 2 6-(Pr2C6H3)-Pr-i 6-Et2C6H3 6-Me2C6H3 6-Me2C6H2 6-Me2C6H2 4 Mt = Fe (1b) Mt = Co (1c) Mt = Fe (1d) Mt = Fe (1e) Mt = Fe (1f) 6-Me3C6H2 Co (2b) Ni (3c) Co (2d) Co (2e) Co (2f)) were synthesized. At the presence of methylaluminoxane (MAO) Mt = Fe (1a) Fe(II)- and Co(II)- based complexes were highly active towards ethylene polymerization Co (2a) affording polymers with bimodal and unimodal molar. mass distributions Ni (3a) respectively while the Ni(II)-based complexes gave no polymer products. Moreover the obtained polyethylenes were predominately saturated and vinyl-terminated for Fe(II)- and Co(II)-based complexes respectively. Changing the ligand environment polymerization parameters also posed a great influence on the catalytic activities and the properties of the resulting polymers. (C) 2014 Elsevier Ltd. All rights reserved.

Contrasting enantioselective DNA preference: chiral helical macrocyclic lanthanide complex binding to DNA 期刊论文 OAI收割
nucleic acids research, 2012, 卷号: 40, 期号: 16, 页码: 8186-8196
Zhao CQ; Ren JS; Gregolinski J; Lisowski J; Qu XG

收藏 | 浏览/下载：27/0 | 提交时间：2013/10/09

G-QUADRUPLEX DNA B-A TRANSITION TELOMERASE ACTIVITY MOLECULAR RECOGNITION FLANKING SEQUENCE METAL-COMPLEXES ACID COMPLEX SITE INTERCALATORS SELECTIVITY

Synthesis and luminescence properties of Eu3+-doped silicate nanomaterial (EI CONFERENCE) 会议论文 OAI收割
17th International Conference on Dynamical Processes in Excited States of Solids, DPC'10, June 20, 2010 - June 25, 2010, Argonne, IL, United states
作者: Zhang J.; Zhang J.; Zhang J.

收藏 | 浏览/下载：29/0 | 提交时间：2013/03/25

In this paper we introduce a sol-gel process for preparing Y 2Si2O7: Eu3+ nanocrystals. The rare earth compounds were dispersed in the SiO2 colloids and the monodisperse nano-scale composite materials were prepared. The reactant mass fraction and heat treatment temperatures could affect the structures and emission spectrum properties of as-synthesized samples. The samples emit the strong red light upon excitation under the ultraviolet. The main peaks originate from 5D0-7F2 electric dipole transition of Eu3+. With regard to the samples treated at different temperatures the emission spectra obtained under 266 nm excitation show different shapes of spectra lines and relative intensities indicating that the Eu3+ ions have been located in different local environments. 2011 Published by Elsevier B.V.

Structural and photoluminescence properties of aligned Sb-doped ZnO nanocolumns synthesized by the hydrothermal method (EI CONFERENCE) 会议论文 OAI收割
作者: Wang X.; Wang X.; Wang X.

收藏 | 浏览/下载：24/0 | 提交时间：2013/03/25

Aligned Sb-doped ZnO nanocolumns were synthesized by a simple hydrothermal method. Based on the analyses of the X-ray diffraction and photoluminescence result it could be confirmed that the Sb has successfully doped in the ZnO crystal lattices to form an accepter energy level. At 85 K the recombination of the acceptor-bound exciton was predominant in PL spectrum which was attributed to the transition of the (SbZn-2VZn) complex bound exciton. The acceptor binding energy had been calculated to be 123 meV. 2009 Published by Elsevier B.V. All rights reserved.

Structure and electric transport properties of the spin ladder compound Sr(14) (Cu(0.97) M(0.03))(24) O(41) (M = Zn, Ni, Co) 期刊论文 OAI收割
Acta Physica Sinica, 2010, 卷号: 59, 期号: 2, 页码: 1155-1162
L. Cheng; L. L. Wang; S. Z. Pu; N. Hu; Y. Zhang; Y. Liu; W. Wei; R. Xiong; J. Shi

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spin ladder compound Sr(14)Cu(24)O(41) B-site doping transport property metal-insulator-transition single-crystals sr(14-x)a(x)cu(24)o(41) sr14cu24o41 dynamics charge la gap ca

Er3+-Doped lutetium borosilicate glass for optical signal amplification at 1.5 m (EI CONFERENCE) 会议论文 OAI收割
Infrared Components and their Applications, November 8, 2004 - November 11, 2004, Beijing, China
作者: Wang X.; Wang X.; Wang X.; Zhang J.; Zhang J.

收藏 | 浏览/下载：18/0 | 提交时间：2013/03/25

A new glass of Lu2O3-B2O 3-SiO2-Na2O-Er2O3 system is prepared by the technique of high-temperature melting at different temperatures and the formation range of the glass is experimentally obtained. Effects of the B2O3 content on the infrared spectral properties such as the 1.5 m emission bandwidth corresponding to 4I13/2&rarr4I15/2 transition and the Judd-Ofelt parameter t (t = 2 4 6) of Er3+ ions in the glass has been observed. The glass exhibits big integrated emission cross sections for the 1.5 m emission band. Excellent thermal stability of the glass has been demonstrated using differential thermal analysis. The Er 3+-doped lutetium borosilicate glass is a great candidate for broadband erbium doped fiber amplifiers.

NONLINEAR TEMPERATURE-DEPENDENCE OF RESISTIVITY IN BI2SR2CUOY CRYSTALS 期刊论文 OAI收割
PHYSICAL REVIEW B, 1993, 卷号: 48, 期号: 18, 页码: 14005
WANG, NL; RUAN, KQ; YANG, LM; WANG, CY; CAO, LZ; CHEN, ZJ; WU, WB; ZHOU, GE; ZHANG, YH

收藏 | 浏览/下载：23/0 | 提交时间：2014/02/20

A-B PLANE TRANSPORT-PROPERTIES TRANSITION SUPERCONDUCTIVITY LA2-XSRXCUO4 ANISOTROPY