The free surface on a simple fluid between cylinders undergoing torsional oscillations. Part III: Oscillating planes

Archive for Rational Mechanics and Analysis -     

On extractant properties of β-ketophosphonates-I: Lanthanides extraction from perchlorate medium by dibutylphenacylphosphonate

Liquid-liquid distribution of lanthanides was studied using dibutylphenacylphosphonate (HDBPP) in an aromatic diluent as organic phase and lM sodium perchlorate as the aqueous phase. Appropriate radioactive isotopes of the elements were used as indicators in the determination of the distribution ratios. HDBPP was found to act both as a neutral and an acidic extracting agent, the extracted species having the general composition [M{H(DBPP)_3-q}_x,(ClO₄)_q]. x = 4, q = 1 were found for M = La and x = 3, q = O for M = Eu, Gd, Tb and Tm. The separation factors of adjacent elements α_z/z-1 and with respect to lanthanum α_z/La were determined for all elements, except cerium. In a plot of α_z/La as a function of z, the dividing of the series into subgroups is discussed in terms of ionic radius, coordination numbers and nephelauxetic effect.     

Continuing studies of noise and cardiovascular function

Long term trends in heart rate were observed in a free-moving rhesus monkey. Initially, normal heart rate for the animal was defined over a span of 4 months. She was then exposed to a community noise recording 12 hours per day for 7 weeks. Pre- and post-exposure changes were noted in several aspects of cardiac function. During the exposure period, heart rate and proportion of aberrant EKG responses rose significantly above, then fell significantly below, baseline levels. Patterns of diurnal rhythm for early morning heart rate were also altered by noise exposure. These last results are consistent with those of an earlier study in which a restrained animal was subjected to similar stimulus conditions. The after effects of the single, prolonged noise exposure episode have dissipated gradually. During the course of a 4 month post-exposure period, heart rate and proportion of aberrant EKG responses have slowly returned to near baseline levels. Early morning diurnal rhythm for heart rate has not yet returned to its pre-exposure pattern.     

An internal coordinate invariant reaction pathway

In this work we show that some properties of a potential energy surface are not independent of the choice of the coordinate frame. So the reaction pathway often described as steepest descent way does not correspond to an invariant curve under coordinate transformations. We propose an internal intrinsic reaction pathway by using some quasi-dynamical considerations (like instantaneous internal acceleration). Our work precises the intrinsic-reaction coordinates of Fukui to any set of 3N-6 internal parameters. Finally, from the equations of motion we deduce the form of the normal reaction coordinates frame anywhere along the postulated reaction pathway.     

Diffraction of light by phase-shifted adjacent ultrasound beams; ρ ⪢ 1

The system of difference-differential equations for the amplitudes of a diffracted light-wave caused by two adjacent ultrasonic beams, a fundamental followed by its nth harmonic, is solved for values of ρ outside the Raman-Nath region, and simplified expressions are deduced for the intensities up to order n. Conclusions are drawn concerning the influence of the phase-shift δ on the diffraction spectrum, and the calculation of the factor α_n from the intensities (α_n represents the ratio of the ultrasonic pressures). All results are applied to the case of a fundamental and its third or fourth harmonic.     

Extraction of indium(III) from chloride medium with 1-phenyl-3-methyl-4-acylpyrazol-5-ones. Synergic effect with high molecular weight ammonium salts.

The extraction of In(III) from 1M (Na,H)(Cl,ClO₄) media with 4-acylpyrazol-5-ones (HL) in toluene at 25°C is described by equilibria In ³⁺ + 3 $\text{HL}$ ? $\text{InL}{}_3$ + 3 H⁺ (log K = 1.48, 1.03, 0.87 with acyl = benzoyl, lauroyl, 2-thenoyl), InCl ²⁺ + 2 $\text{HL}$ ? $\text{InClL}{}_2$ + 2 H⁺ (log K = 0.26, ?0.45, ?0.35 respectively) and In³⁺ + m Cl^? ? InCl_m^(3-m)+ (log β_m available from literature). The extraction from 1M (Na,H)(Cl,NO₃) medium is enhanced by addition of aliquat (TOMA⁺,Cl^?) and the following synergic equilibrium takes place : $\text{InCl}{}_2$ + $\text{(TOMA}{}^{\mathrm{+}}$,Cl^?) ? $\text{(TOMA}{}^{\mathrm{+}}$, InCl₂L₂^? (log K = 5.49, 5.25, 5.21 respectively). Cl^? of (TOMA⁺,Cl^?) is exchanged by NO₃^? with the equilibrium constant log K = 1.50. If (TOMA⁺,Cl^?) is replaced by tri-n-octylammonium chloride, the synergic effect is largely reduced (log K = 4.17 with acyl = benzoyl). The extraction from chloride solutions containing ClO₄^? remains unchanged by addition of ammonium salts.     

Chlorobromoantimonates(V): New synthesis and 121Sb-NMR study

The new tetraethylammonium tetrachlorodibromoantimonate(V) and dichlorotetrabromoantimonate(V) have been prepared and have been given a cis-structure from their vibrational spectra. The ways of synthesis of all the terms of the series NEt₄⁺SbCl_6?nBr_n^? are discussed; the ¹²¹Sb spectra of their solutions in CH₃CN are given and show halide exchange around Sb(V).