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91.
We report the first direct evidence of detuning of stimulated Brillouin scattering (SBS) by a velocity gradient, which was achieved by directly measuring the frequency shift of the SBS-driven acoustic wave relative to the local resonant acoustic frequency. We show that in the expanding part of the plasma, ion-acoustic waves are driven off resonance which leads to the saturation of the SBS instability. These measurements are well reproduced by fluid simulations that include the measured flow. 相似文献
92.
Delta wells can become charge-depleted through background doping, or as part of asymmetric n-i-p-i structures. For moderate depletions, the electronic properties of the residual 2DEGs in these cases are similar. For moderate depletion by background doping, the charge removed from the well varies inversely with the square-root of the background intensity, independent of the strength of the delta well. Depletion of delta wells is found to procede in a ‘top-down’ fashion in a 2-dimensional analogue to atomic ionization. 相似文献
93.
A magnetized Iron CALorimeter (ICAL) detector at the India-based neutrino observatory (INO) is used to study neutrino oscillation sensitivity using atmospheric muon neutrino source. The ICAL detector will be able to detect muon tracks and hadron showers produced by neutrino interactions with the iron target. We have performed precision measurement analysis for the atmospheric neutrino oscillation parameters with the muon neutrino events, generated by Monte Carlo NUANCE event generator. A marginalized χ2 analysis based on reconstructed neutrino energy and muon zenith angle binning scheme has been performed to determine the sensitivity for the atmospheric neutrino mixing parameters, \(\sin ^{2}\theta _{23}\) and \(| {\Delta } m^{2}_{23}|\). 相似文献
94.
Calculation of photon dispersion relations 总被引:2,自引:0,他引:2
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98.
For ?1≤B<A≤1, let \(\mathcal {S}^{*}(A,B)\) denote the class of normalized analytic functions \(f(z)= z+{\sum }_{n=2}^{\infty }a_{n} z^{n}\) in |z|<1 which satisfy the subordination relation z f ′(z)/f(z)?(1 + A z)/(1 + B z) and Σ?(A,B) be the corresponding class of meromorphic functions in |z|>1. For \(f\in \mathcal {S}^{*}(A,B)\) and λ>0, we shall estimate the absolute value of the Taylor coefficients a n (?λ,f) of the analytic function (f(z)/z)?λ . Using this we shall determine the coefficient estimate for inverses of functions in the classes \(\mathcal {S}^{*}(A,B)\) and Σ?(A,B). 相似文献
99.
G. Thirupathi E. Yadaiah Goud Y. Hemasri MD. Suban Ali Y. Jayaprakash Rao 《Journal of the Iranian Chemical Society》2017,14(2):477-483
A facile, convenient, efficient and high-yielding synthesis of 3-aroylcoumarinoflavones has been developed by the condensation of easily synthesized 7-hydroxy-8-formylflavones and benzoyl acetonitriles in the presence of catalytic amount of l-proline in ethanol reflux. All the synthesized compounds were evaluated for their antioxidant activity. Some of the compounds showed very good activity compared to standard BHT. 相似文献
100.
Daniel A Paterson Jordan P Abberley William TA Harrison John MD Storey 《Liquid crystals》2017,44(1):127-146
ABSTRACTThe synthesis and characterisation of several members of the 1,ω-bis(4-cyanobiphenyl-4′-yl) alkane (CBnCB) and the 1-(4-cyanobiphenyl-4′-yloxy)-ω-(4-cyanobiphenyl-4′-yl) alkane (CBnOCB) homologous series are reported. The new odd members described CB5CB, CB13CB, CB4OCB, CB8OCB and CB10OCB all exhibit twist-bend nematic and nematic phases. The members of these series already reported in literature, CB7CB, CB9CB, CB11CB and CB6OCB, were also prepared in order to allow for a direct comparison of their transitional properties. The properties of these dimers are also compared to those of the corresponding members of the 1,ω-bis(4-cyanobiphenyl-4,-yloxy) alkanes (CBOnOCB). For any given total spacer length, for odd members of these series, the nematic–isotropic transition temperatures and associated entropy changes are greatest for the CBOnOCB dimer and lowest for the CBnCB dimer. These trends are understood in terms of molecular shape. For short spacer lengths, the twist-bend nematic–nematic transition temperature (TNTBN) is higher for the CBnOCB series than for the CBnCB series but this is reversed as the spacer length increases. Of the CBOnOCB dimers, a virtual value of TNTBN was estimated for CBO3OCB and TNTBN was measured for CBO5OCB. These values are considerably lower than those observed for the corresponding members of the CBnCB or CBnOCB series. The dependence of TNTBN on molecular structure is discussed not only in terms of the molecular curvature but also in the ability of the molecules to pack efficiently. As the temperature range of the preceding nematic phase increases, so the twist-bend nematic–nematic transition entropy change decreases and the transition approaches second order for the longer spacers. For comparative purposes, the transitional behaviour of the even-membered dimers CB6CB, CB5OCB and CBO4OCB is reported and differences accounted for in terms of molecular shape. 相似文献