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1.
Bao Nguyen Xuan Duy Khanh Phan Quoc Tung Nguyen Minh 《Set-Valued and Variational Analysis》2022,30(2):465-486
Set-Valued and Variational Analysis - We aim to establish Karush-Kuhn-Tucker multiplier rules involving higher-order complementarity slackness under Hölder metric subregularity. These rules... 相似文献
2.
D. Liu N.Q. Ngo X.Y. Dong S.C. Tjin P. Shum 《Applied physics. B, Lasers and optics》2005,81(6):807-811
We propose and experimentally demonstrate a stable dual-wavelength erbium-doped polarization-maintaining (PM) fiber laser
with tunable wavelength spacing using an all-PM linear cavity that makes use of two reflection peaks from the PM fiber Bragg
grating (PM-FBG). Experimental results show stable dual lasing lines with a wavelength separation of ∼0.22 nm and a large
optical signal-to-noise ratio (OSNR) of over 40 dB under room temperature. By applying axial strain to the PM-FBG, the center
wavelengths of the two lasing lines can be tuned over several nanometers and the wavelength separation between the lasing
lines can also be tuned to as small as 0.05 nm, which, to our knowledge, is the smallest wavelength spacing ever obtained
from a stable room-temperature dual-wavelength fiber laser. The proposed laser configuration has the advantages of simple
structure, low loss, stable dual-wavelength operation and a very small lasing linewidth of ∼5 kHz .
PACS 42.55.Wd; 42.81.-i; 42.81.Gs 相似文献
3.
Ngo Quang Huy Trinh Thi Bich Nguyen Van Suc 《Journal of Radioanalytical and Nuclear Chemistry》2006,269(1):129-133
Summary The paper presents a procedure to prepare soil samples for U and Th isotope measurement by alpha-spectrometry after coprecipitation
with LaF3. In this procedure the reduction of U(VI) to U(IV) was performed by Zn metal in 4M HCl solution. The recoveries of chemical
separation equal to eU-chemistry = 78±4% for uranium and eTh-chemistry = 82±4% for thorium. Canberra alpha-spectrometer was used with PIPS detectors of A-1200-37-AM Model of 1200 mm2 active area. The counting efficiency of the measuring system equals to ecounting = 18% and the total efficiencies were eU = ecounting .eU-chemistry = 14.0±0.7% for uranium and eTh = ecounting .eTh-chemistry = 14.7±0.7% for thorium. The recoveries of chemical separation were rather high (about 80%), that leads to the use of a small
weight of soil sample (about 0.5 g). The efficiencies were also stable, that allows analyzing the soil sample without using
radiotracers. They are advantages of the sample preparation procedure of this work. 相似文献
4.
The deposition of decomposed ethylene on silicon wafer at lower temperature using hot filament chemical vapor deposition (HFCVD) method was applied to compose thin film of carbon and its compounds with silicon and hydrocarbon structures. The films were analyzed using Raman spectroscopy, X-ray diffraction, and scanning electron microscopy with elemental microanalysis by energy dispersive X-ray spectrometer. The structure and morphology of the early stage of the film deposition was analyzed. The obtaining of SiC as well as diamond-like structure with this method and catalytic influence of chemical admixtures on the film structure and properties are discussed. 相似文献
5.
6.
Mitsunori Oda Yosuke Fukuchi Satoshi Ito Nguyen Chung Thanh Shigeyasu Kuroda 《Tetrahedron letters》2007,48(52):9159-9162
Reactions of pyrrolidine with 2 equiv of aldehydes without any catalyst in a pressurized vessel at 140–200 °C yielded 1,3-disubstituted pyrroles. -Branched aldehydes gave fairly good yields of the corresponding products by this method, which provides a facile non-oxidative procedure for synthesizing 1,3-dialkylpyrroles from inexpensive pyrrolidine and aldehydes. 相似文献
7.
Nguyen Hoa Hong Joe Sakai Ngo Thu Huong Virginie Brizé 《Journal of magnetism and magnetic materials》2006
Laser-ablated Co-doped In2O3 thin films were fabricated under various growth conditions on R-cut Al2O3 and MgO substrates. All Co:In2O3 films are well-crystallized, single phase, and room temperature ferromagnetic. Co atoms were well substituted for In atoms, and their distribution is greatly uniform over the whole thickness of the films. Films grown at 550 °C showed the largest magnetic moment of about 0.5 μB/Co, while films grown at higher temperatures have magnetic moments of one order smaller. The observed ferromagnetism above room temperature in Co:In2O3 thin films has confirmed that doping few percent of magnetic elements such as Co into In2O3 could result in a promising magnetic material. 相似文献
8.
We calculate one-loop radiative QCD corrections to the three polarized and unpolarized structure functions that determine the beam-quark polar angle dependence of the longitudinal polarization of light and heavy quarks produced in e+e?-annihilations. We present analytical and numerical results for the longitudinal polarization and its polar angle dependence. We discuss in some detail the zero-mass limit of our results and the role of the anomalous spin-flip contributions to the polarization observables in the zero-mass limit. Our discussion includes transverse and longitudinal beam polarization effects. 相似文献
9.
10.
Application of the refined Wiener-Hermite expansion with moderate to high Reynolds numbers Re to homogeneous, isotropic turbulence is presented. The results show a defect to Kolmogorov's five-thirds law, increase in the absolute value of the exponent comparable with many theoretical predictions. Midrange spectra up to fluctuation Reynolds numbers of 108 show little, if any, dependence of the defect on Re, as long as the initial spectra do not deviate too far from their equilibrium states. The renormalization scheme has also been proven to have no effect on the final shape of the spectrum. 相似文献