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91.
Iman Evazzade Mahmood Rezaee Roknabadi Mohammad Behdani Fatemeh Moosavi Daxing Xiong Kun Zhou Sergey V. Dmitriev 《The European Physical Journal B - Condensed Matter and Complex Systems》2018,91(7):163
We numerically analyze the interaction of small-amplitude phonon waves with standing gap discrete breather (DB) in strained graphene. To make the system support gap DB, strain is applied to create a gap in the phonon spectrum. We only focus on the in-plane phonons and DB, so the issue is investigated under a quasi-one-dimensional setup. It is found that, for the longitudinal sound waves having frequencies below 6 THz, DB is transparent and thus no radiation of energy from DB takes place; whereas for those sound waves with higher frequencies within the acoustic (optical) phonon band, phonon is mainly transmitted (reflected) by DB, and concomitantly, DB radiates its energy when interacting with phonons. The latter case is supported by the fact that, the sum of the transmitted and reflected phonon energy densities is noticeably higher than that of the incident wave. Our results here may provide insight into energy transport in graphene when the spatially localized nonlinear vibration modes are presented. 相似文献
92.
A novel, 100% water-soluble chalcone based chemosensing receptor {1-[3-(2-Hydroxy-phenyl)-3-oxo-propenyl]-naphthalen-2-yloxy}-acetic acid, L was synthesized and characterized. The receptor L is designed based on the chelation enhanced fluorescence (CHEF) mechanism. The chemosensing properties of L were evaluated by UV–vis and fluorescence spectrometric methods. It exhibits highly selective recognition ability towards aluminum ions in water over other metal ions. The binding stoichiometry of L? Al3+ complex is 2:1 by means of Job’s plot and the detection limit is 5.66?×?10??8 M. 相似文献
93.
S. Mahmood N. Akhtar 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,49(2):217-222
Linear and nonlinear ion acoustic waves in the presence of adiabatically heated ions in magnetized electron-positron-ion plasmas
are studied. The Sagdeev potential approach is employed to obtain the energy integral equation in such a mulitcomponent plasma
using fluid theory. It is found that electron density humps are formed in the subsonic region in magnetized electron-positron-ion
plasmas. The amplitude of electron density hump is decreased with the increase of hot ion temperature in electron-positron-ion
plasmas. However, the increase in positron concentration and obliqueness of the wave increases the amplitude of nonlinear
structure. The increase in positron concentration also reduces the width of the nonlinear structure in a magnetized multicomponent
plasma. The numerical solutions in the form of solitary pulses are also presented for different plasma cases. The results
may be applicable to astrophysical plasma situations, where magnetized electron-positron-ion plasma with hot ions can exist. 相似文献
94.
An efficient and simple synthesis of α‐hydroxyphosphonates via reaction of aldehydes and ketones with dimethylphosphite in the presence of MgCl2/Et3N base system is reported. The use of readily available and easy to handle reagent MgCl2/Et3N makes this method simple, convenient, and practical. 相似文献
95.
An analytical method is described for the analysis of antazoline [2-(N-benzylanilinomethyl) imidazoline] using pmr. The procedure provides good quantitative results together with a very specific mean for identification of antazoline 相似文献
96.
Ratiometric fluorescent chemosensors based on the position of ring annulation of the naphthol–thiazole moiety for quantification of zinc ions in aqueous ethanol were synthesized and investigated. It was found that sensor 3 exhibited a remarkably large red shift of 140 nm in emission upon complexation with Zn2+. A TD-B3LYP/6-31G (d,p) calculation was performed to characterize the nature of the fluorescence behavior of sensor 3 upon Zn2+ complexation. The combination of experimental and computational analyses provides a more complete understanding of the molecular level origin of these unique photophysical properties of this type of chemosensor. 相似文献
97.
We comment on the paper [Song et al., J. Comput. Chem. 2009, 30, 399]. and discuss the efficiency of the orbital optimization and gradient evaluation in the Valence Bond Self Consistent Field (VBSCF) method. We note that Song et al. neglect to properly reference Broer et al., who published an algorithm [Broer and Nieuwpoort, Theor. Chim. Acta 1988, 73, 405] to use a Fock matrix to compute a matrix element between two different determinants, which can be used for an orbital optimization. Further, Song et al. publish a misleading comparison with our VBSCF algorithm [Dijkstra and van Lenthe, J. Chem. Phys. 2000, 113, 2100; van Lenthe et al., Mol. Phys. 1991, 73, 1159] to enable them to favorably compare their algorithm with ours. We give detail timings in terms of different orbital types in the calculation and actual timings for the example cases. © 2012 Wiley Periodicals, Inc. 相似文献
98.
Eckhart E Gan KK Gwon C Hart T Honscheid K Hufnagel D Kagan H Kass R Pedlar TK Thayer JB Von Toerne E Wilksen T Zoeller MM Muramatsu H Richichi SJ Severini H Skubic P Dytman SA Mueller JA Nam S Savinov V Chen S Hinson JW Lee J Miller DH Pavlunin V Shibata EI Shipsey IP Cronin-Hennessy D Lyon AL Park CS Park W Thorndike EH Coan TE Gao YS Liu F Maravin Y Stroynowski R Artuso M Boulahouache C Bukin K Dambasuren E Khroustalev K Mountain R Nandakumar R Skwarnicki T Stone S Wang JC Mahmood AH 《Physical review letters》2002,89(25):251801
We report on a search for charmless hadronic B decays to the three-body final states K(0)(S)h(+)pi(-), K(+)h(-)pi(0), K(0)(S)h(+)pi(0) (h(+/-) denotes a charged pion or kaon), and their charge conjugates, using 13.5 fb(-1) of integrated luminosity produced near sqrt[s]=10.6 GeV, and collected with the CLEO detector. We observe the decay B-->K0pi(+)pi(-) with a branching fraction (50(+10)(-9)(stat.)+/-7(syst.))x10(-6) and the decay B-->K(*+)(892)pi(-) with a branching fraction (16(+6)(-5)(stat.)+/-2(syst.))x10(-6). 相似文献
99.
Summary This paper deals with testing the hypothesis of independence of two attributes inr×c Markovian Contingency tables. Likelihood ratio test and χ2-test of the form used in contingency tables are proposed. It is observed that both likelihood ratio criterion and χ2-test lead to the same test statistic in the sense that −2 log λ and χ2-test have asymptotically the same distribution. 相似文献
100.