Search results for "Mixing"

Efficient metallic spintronic emitters of ultrabroadband terahertz radiation

2016

Terahertz electromagnetic radiation is extremely useful for numerous applications such as imaging and spectroscopy. Therefore, it is highly desirable to have an efficient table-top emitter covering the 1-to-30-THz window whilst being driven by a low-cost, low-power femtosecond laser oscillator. So far, all solid-state emitters solely exploit physics related to the electron charge and deliver emission spectra with substantial gaps. Here, we take advantage of the electron spin to realize a conceptually new terahertz source which relies on tailored fundamental spintronic and photonic phenomena in magnetic metal multilayers: ultrafast photo-induced spin currents, the inverse spin-Hall effect an…

A thermodynamic approach to study hydrogen-bonding interactions in solvent/solvent/polymer ternary systems

2007

Abstract A thermodynamic approach based on both the classical Flory–Huggins (FH) formalism and the association equilibria (AE) theory has been developed to study the solubility properties of a system formed by a proton-donor solvent (A), a proton-acceptor solvent (B) and a proton-acceptor polymer (C). The miscibility of this ternary system is attained by competitive specific interactions via hydrogen-bonding established between the hydroxyl and carbonyl interacting groups of either solvent–solvent (AB) or solvent–polymer (AC) system components. The binary AB and AC specific interactions and their dependence with the system composition as well as with the extent of the association equilibriu…

Evaluation of thermodynamic parameters for blends of polyethersulfone and poly(methyl methacrylate) or polystyrene in dimethylformamide

1998

Liquid-liquid phase separation phenomena have been investigated for a ternary system containing two polymers and a solvent. Namely, dimethylformamide (DMF)/polyethersulfone (PES)/poly(methyl methacrylate) (PMMA) and DMF/PES/Polystyrene (PS). The composition of the three components in the two phases in equilibrium has been determined by size exclusion chromatographic (s.e.c.) analysis. The lattice-based mean-field theory, first developed by Flory and Huggins, has been modified to adequately describe these systems. In this respect, we have assumed that the parameters depend on the polymer concentration, and we have included a ternary parameter. The phase equilibrium compositions have been use…

Formation of metastable structures by phase separation triggered by initial composition gradients in thin films.

2012

Phase separation kinetics of a binary (A,B) mixture contained in a thin film of thickness D induced by a quench from the one-phase region into the miscibility gap is studied by simulations using a Cahn-Hilliard-Cook model. The initial randomly mixed state (50% A, 50% B) contains a concentration gradient perpendicular to the film, while the surfaces of the film are "neutral" (no preference for either A or B). In thermal equilibrium, a pattern of large A-rich and B-rich domains must result, separated by domain walls oriented perpendicularly to the external surfaces of the thin film. However, it is shown that for many choices of D and the strength of the initial gradient Ψ(g), instead a very l…

Intracavity Frequency Doubling and Difference Frequency Mixing for Pulsed ns Ti:Sapphire Laser Systems at On-Line Radioactive Ion Beam Facilities

2015

Intra-cavity second harmonic generation of a Titanium:sapphire (Ti:sa) laser system has been used to improve the conversion efficiency to the second harmonic. Over the course of several experiments performance data spanning the whole wavelength range of a Ti:sa has been collected, which may be used as a guideline for future experiments. An average output power of up to 3.7 W was achieved, resulting in a conversion efficiency of >75 % to the second harmonic. A wavelength coverage from 340-525 nm has been demonstrated. To extend the wavelength range of the solid state laser system, difference frequency mixing has been applied to the intra-cavity doubled light and the fundamental output of a s…

Projective metrics and mixing properties on towers

2001

Model for T2K indication with maximalθ23and trimaximalθ12

2011

Recently T2K experiment gives hint in favor of large reactor angle ${\ensuremath{\theta}}_{13}$. Most of the models, with tribimaximal mixing at the leading order, can not reproduce such a large mixing angle since they predict typically corrections for the reactor angle of the order ${\ensuremath{\theta}}_{13}\ensuremath{\sim}{\ensuremath{\lambda}}_{C}^{2}$, where ${\ensuremath{\lambda}}_{C}\ensuremath{\sim}0.2$. In this paper, we discuss the possibility to achieve large ${\ensuremath{\theta}}_{13}$ within the T2K region with maximal atmospheric mixing angle, ${sin}^{2}{\ensuremath{\theta}}_{23}=1/2$, and trimaximal solar mixing angle, ${sin}^{2}{\ensuremath{\theta}}_{12}=1/3$, through th…

S-4 as a natural flavor symmetry for lepton mixing

2008

Group theoretical arguments seem to indicate the discrete symmetry S4 as the minimal flavour symmetry compatible with tribimaximal neutrino mixing. We prove in a model independent way that indeed S4 can realize exact tribimaximal mixing through different symmetry breaking patterns. We present two models in which lepton tribimaximal mixing is realized in different ways and for each one we discuss the superpotential that leads to the correct breaking of the flavor symmetry.

2013

Abstract. It has become possible to retrieve the global, long-term trends of trace gases that are important to atmospheric chemistry, climate, and air quality from satellite data records that span more than a decade. However, many of the satellite remote sensing techniques produce measurements that have variable sensitivity to the vertical profiles of atmospheric gases. In the case of constrained retrievals like optimal estimation, this leads to a varying amount of a priori information in the retrieval and is represented by an averaging kernel (AK). In this study, we investigate to what extent the estimation of trends from retrieved data can be biased by temporal changes of averaging kernel…

Kodu jaukšana latviešu digitālā satura autoru Instagram ziņās

2022

Mūsdienās angļu valodai ir liela nozīme ikdienas dzīvē un tā ir neatņemama saziņas sastāvdaļa starptautiskajās attiecībās, informācijas ieguvē, mācībās un sociālajā attīstībā. Angļu valodas kā lingua franca statuss noved pie tās tālākas iefiltrēšanās visās dzīves jomās, un valodas kontakts ir viena no tām. Īpaši valodas lietojumu un izmaiņas visprecīzāk var novērot sociālajos medijos. Sociālo mediju platformas sniedz daudz dažādu analizējamu datu. Šajā pētījumā tiek aplūkoti Latvijas digitālā satura autoru Instagram ieraksti ar mērķi analizēt, kā viņi izmanto kodu jaukšanu. Izmantojot kvantitatīvās un kvalitatīvās metodes, analizējot korpusu, kas apkopots no piecpadsmit Latvijas influenceru…