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81.
This paper aims at investigating the detailed structure of turbulent non-reacting dilute spray flows using advanced laser diagnostics. A simple spray jet nozzle is designed to produce a two-phase slender shear flow in a co-flowing air stream with well-defined boundary conditions. The carrier flow is made intentionally simple and easy to model so that the focus can be placed on the important aspects of droplet dispersion and evaporation, as well as turbulence–droplet interactions. Phase Doppler interferometry is employed to record droplet quantities, while planar laser-induced fluorescence imaging is applied separately to obtain acetone vapour data. Measurements are conducted for four acetone spray jets in air at several axial stations starting from the nozzle exit. The combined liquid and vapour mass fluxes of acetone integrated across the jet at downstream locations agree satisfactorily with the total mass flow rate of acetone injected. 相似文献
83.
Javier Ramos‐Soriano Ulf Niss Dr. Jesús Angulo Dr. Manuel Angulo Dr. Antonio J. Moreno‐Vargas Dr. Ana T. Carmona Prof. Dr. Sten Ohlson Prof. Dr. Inmaculada Robina 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(52):17989-18003
The synthesis of several non‐carbohydrate ligands of cholera toxin based on polyhydroxyalkylfuroate moieties is reported. Some of them have been linked to D ‐galactose through a stable and well‐tolerated S‐glycosidic bond. They represent a novel type of non‐hydrolyzable bidentate ligand featuring galactose and polyhydroxyalkylfuroic esters as pharmacophoric residues, thus mimicking the GM1 ganglioside. The affinity of the new compounds towards cholera toxin was measured by weak affinity chromatography (WAC). The interaction of the best candidates with this toxin was also studied by saturation transfer difference NMR experiments, which allowed identification of the binding epitopes of the ligands interacting with the protein. Interestingly, the highest affinity was shown by non‐carbohydrate mimics based on a polyhydroxyalkylfuroic ester structure. 相似文献
84.
Patricia Gramming Johan Sundberg Sten Ternstrm Rolf Leanderson William H. Perkins 《Journal of voice》1988,2(2)
Changes in mean fundamental frequency accompanying changes in loudness of phonation are analyzed in 9 professional singers, 9 nonsingers, and 10 male and 10 female patients suffering from vocal functional dysfunction. The subjects read discursive texts with noise in earphones, and some also at voluntarily varied vocal loudness. The healthy subjects phonated as softly and as loudly as possible at various fundamental frequencies throughout their pitch ranges, and the resulting mean phonetograms are compared. Mean pitch was found to increase by about half-semitones per decibel sound level. Grossly, the subject groups gave similar results, although the singers changed voice pitch more than the nonsingers. The voice pitch changes may be explained as passive results of changes of subglottal pressure required for the sound level variation. 相似文献
85.
Anita McAllister Elisabeth Sederholm Sten Ternström Johan Sundberg 《Journal of voice》1996,10(3):252-261
Fundamental frequency (F0) perturbation has been found to be useful as an acoustic correlate of the perception of dysphonia in adult voices. In a previous investigation, we showed that hoarseness in children's voices is a stable concept composed mainly of three predictors: hyperfunction, breathiness, and roughness. In the present investigation, the relation between F0 perturbation and hoarseness as well as its predictors was analyzed in running speech of six children representing different degrees of hoarseness. Two perturbation measures were used: the standard deviation of the distribution of perturbation data and the mean of the absolute value of perturbation. The results revealed no clear relation. 相似文献
86.
Sten Yngström 《International Journal of Theoretical Physics》1994,33(7):1479-1501
The theoretical derivation of a new spectral line intensity formula for atomic radiative emission is presented. The theory is based on first principles of quantum physics, electrodynamics, and statistical physics. Quantum rules lead to revision of the conventional principle of local thermal equilibrium of matter and radiation. Study of electrodynamics suggests absence of spectral emission from fractions of the numbers of atoms and ions in a plasma due to radiative inhibition caused by electromagnetic force fields. Statistical probability methods are extended by the statement: A macroscopic physical system develops in the most probable of all conceivable ways consistent with the constraining conditions for the system. The crucial role of statistical physics in transforming quantum logic into common sense logic is stressed. The theory is strongly supported by experimental evidence. 相似文献
87.
88.
Britt Friis‐Jensen David L. Cooper Sten Rettrup 《Journal of mathematical chemistry》1997,22(2-4):249-254
We find the normalization integral for projected spin eigenfunctions, defined by means of character projection operators of
the symmetric group. We also obtain a reduced expression for these spin eigenfunctions.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
89.
Lars-Gunnar Johansson Carin Str m Sten Eriksson
Ingrid Bryntse
《Physica C: Superconductivity and its Applications》1994,220(3-4):295-302A new procedure for the preparation of Tl2Ba2CaCu2O8-δ is presented. In the first step stoichiometric amounts of Cu(NO3)2·3H2O, Ba(OH)2·H2O, CaO and Tl2O3 are reacted in a closed alumina crucible at 760°C to form a mixture of Tl- 2212, CuO, CaO and other oxide phases. In the second step this material is milled, pelletized and fired in a gold-sealed alumina crucible at 860–900°C for three to eight hours. Three batches of Tl-2212 prepared by this method were investigated showing less than 1% loss of thallium while Tc was close to 110 K. Rietveld refinements using time-of-flight neutron-diffraction data demonstrate that the method produces pure material in a reproducible way and that the materials are substoichiometric with respect to oxygen (δ=0.3). Investigations using electron diffraction and high-resolution electron microscopy indicate the absence of stacking faults. 相似文献
90.