The Oil Resistance of Rubber. II. Molecular Polarization and Dipole Moment of Purified Natural Rubber

1936 ◽  
Vol 9 (2) ◽  
pp. 296-300
Author(s):  
Shû Kambara
Keyword(s):  
Dielectric Constant ◽  
Refractive Index ◽  
Dipole Moment ◽  
Natural Rubber ◽  
Dipole Moments ◽  
Molecular State ◽  
True Value ◽  
Order Of Magnitude ◽  
Ether Solution ◽  
Constant Refractive Index

Abstract Natural rubber was purified by Pummerer's method and was dissolved in benzene and ether. The dielectric constant, refractive index, density, and concentration of the solutions were determined. From these data, the molecular polarization and dipole moment were calculated on the assumption that the rubber was dissolved in a molecular state of (C5H8)8. The dipole moments of total and gel rubber were found to be 2.45 and 2.91 × 10−18, respectively. These values are of the same order of magnitude as those of masticated crude rubber obtained by Ostwald. It may be said that the impurities of rubber are interlocked mechanically on the rubber molecule and are not combined chemically. Sol rubber in ether solution shows a far lower value than the values of total and gel rubber. These latter values may be influenced by autoöxidation, and the true value of the rubber hydrocarbon may be far smaller than the result described in this paper.

Temperaturabhängigkeit der statischen Dielektrizitätskonstante und des optischen Brechungsindexes von Flüssigkeiten

1975 ◽  
Vol 30 (3) ◽  
pp. 287-291 ◽  
Author(s):  
I. Gryczyński ◽  
A. Kawski
Keyword(s):  
Dielectric Constant ◽  
Refractive Index ◽  
Dipole Moment ◽  
Dipole Moments ◽  
Mixed Solvents ◽  
Temperature Changes ◽  
Temperature Dependences ◽  
Solvent Shifts ◽  
Pure And Mixed Solvents ◽  
Good Agreement

A variation of the temperature changes the static dielectric constant (ε) and the refractive index (n) of solvents and, in conjunction with the measurement of solvent shifts of absorption and fluorescence maxima, allows the investigation of dipole moment changes of solutes in the excited state. For this purpose, investigations of the temperature dependences of ε and n of some pure and mixed solvents of different polarities have been made. It is found that the excited dipole moments of indole, 1,2-dimethylindole, 2,3-dimethylindole and tryptophan obtained from the shifts of the fluorescence maxima in mixed solvents at high temperatures are in good agreement with those obtained in other ways.

π-Elektronen-Dipolmoment eines Pyridinium-N-phenol-betains

1966 ◽  
Vol 21 (9) ◽  
pp. 1373-1376 ◽  
Author(s):  
A. Schweig ◽  
C. Reichardt
Keyword(s):  
Dielectric Constant ◽  
Dipole Moment ◽  
Ground State ◽  
Dipole Moments ◽  
Saturated Hydrocarbon ◽  
Dilute Solution ◽  
Uniform Medium ◽  
Order Of Magnitude ◽  
Dimensional Electron Gas ◽  
Experimental Values

The ground state dipole moment of the π-electrons of 2.4.6-triphenyl-N- [3.5-di-tert-butyl-4-hydroxy-phenyl] -pyridinium-betain I, a highly solvatochromic substance, was determined by measuring the dielectric constant of a dilute solution and calculating first the dipole moment of the whole system (σ- and π-electrons) using the method of HALVERSTADT and KUMLER. The dipole moment of the π-electrons was then calculated, asuming the π-electron dipole to be imbedded in a spherical medium of dielectric constant 2. The value calculated by this method was compared with the π-electron dipole moment directly obtained from the dielectric constant of the dilute solution using a method of H. KUHN. This method is based on the assumption that a π-electron of a dissolved molecule sees the σ-electrons of the molecule and of the surrounding solvent, a saturated hydrocarbon, as a continuous uniform medium of dielectric constant 2. Thus the π-electron dipole of the solute molecule is regarded as being imbedded in a continuous medium of dielectric constant 2. It was found that the values of the π-electron dipole moments determined by the two methods agree well. Furthermore these experimental values agree with a theoretical value obtained in the case of N- [4-hydroxy-phenyl] -pyridinium-betain II using the one dimensional electron gas method including electron repulsion. The order of magnitude of the π-electron dipole moment of I clearly shows that the ground state of this molecule is highly polar.

scholarly journals Manufacturing and investigation of physical properties of polyacrylonitrile nanofibre composites with SiO2, TiO2 and Bi2O3 nanoparticles

2016 ◽  
Vol 7 ◽  
pp. 1141-1155 ◽  
Author(s):  
Tomasz Tański ◽  
Wiktor Matysiak ◽  
Barbara Hajduk
Keyword(s):  
Dielectric Constant ◽  
Refractive Index ◽  
Physical Properties ◽  
Band Gap ◽  
Electrospinning Process ◽  
Nanocomposite Polymer ◽  
Dispersion Of Nanoparticles ◽  
Gap Width ◽  
Band Gap Width ◽  
Constant Refractive Index

The aim of this study was to produce nanocomposite polymer fibres, consisting of a matrix of polyacrylonitrile (PAN) and a reinforcing phase in the form of SiO2/TiO2/Bi2O3 nanoparticles, by electrospinning the solution. The effect of the nanoparticles and the electrospinning process parameters on the morphology and physical properties of the obtained composite nanofibres was then examined. The morphology of the fibres and the dispersion of nanoparticles in their volume were examined using scanning electron microscopy (SEM). All of the physical properties, which included the band gap width, dielectric constant and refractive index, were tested and plotted against the concentration by weight of the used reinforcing phase, which was as follows: 0%, 4%, 8% and 12% for each type of nanoparticles. The width of the band gap was determined on the basis of the absorption spectra of radiation (UV–vis) and ellipsometry methods. Spectroscopic ellipsometry has been used in order to determine the dielectric constant, refractive index and the thickness of the obtained fibrous mats.

Propriétés physiques et basicité de l'oxydipropionitrile

1984 ◽  
Vol 62 (2) ◽  
pp. 361-362 ◽  
Author(s):  
Jean-Claude Bollinger ◽  
Germaine Yvernault ◽  
Théophile Yvernault ◽  
Raymond Houriet
Keyword(s):  
Dielectric Constant ◽  
Refractive Index ◽  
Dipole Moment ◽  
Chemical Shift ◽  
Gas Phase ◽  
Solubility Parameter ◽  
Donor Number ◽  
Proton Chemical Shift ◽  
Acid Base ◽  
Propriétés Physiques

Physical constants (density, refractive index, viscosity, dielectric constant, dipole moment, solubility parameter) and some basicity parameters (donor number, proton chemical shift variation for CHCl3, gas phase basicity) have been determined for 3,3′-oxydipropionitrile (ODPN) at 25 °C. These results are compared with those for other usual solvents; they permit an explanation of its properties as a solvent for acid–base titrations, and the appearance of homohydrogen bonding in this medium.

scholarly journals Sensitivity measuring expected on the electromagnetic anomalous couplings in the tt̄γ vertex at the FCC-he

2020 ◽  
Vol 35 (28) ◽  
pp. 2050178
Author(s):  
M. Köksal ◽  
A. A. Billur ◽  
A. Gutiérrez-Rodríguez ◽  
M. A. Hernández-Ruíz
Keyword(s):  
Electron Beam ◽  
Dipole Moment ◽  
Top Quark ◽  
Dipole Moments ◽  
Production Cross ◽  
Anomalous Couplings ◽  
Decay Modes ◽  
Effective Lagrangian ◽  
Order Of Magnitude ◽  
Text Interaction

Starting from an effective Lagrangian for the [Formula: see text] interaction of the top-quark, we consider the electroweak production cross-section via charged current and through the [Formula: see text] signal. Further, we derive the sensitivity expected for the magnetic dipole moment [Formula: see text] and the electric dipole moment [Formula: see text] of the top-quark at the Future Circular Collider-hadron electron (FCC-he). We present our study for [Formula: see text], 10 TeV, [Formula: see text], 100, 300, 500, 1000 fb[Formula: see text], [Formula: see text] and [Formula: see text], 80%, [Formula: see text], respectively. We find that the sensitivity estimated on dipole moments of the top-quark is of the order of magnitude [Formula: see text] for both hadronic and leptonic decay modes of [Formula: see text]: [Formula: see text] and [Formula: see text] at 95% C.L. in the hadronic channel with unpolarized electron beam [Formula: see text]. Our results regarding the polarized electron beam for [Formula: see text] and [Formula: see text] are [Formula: see text], [Formula: see text] and [Formula: see text], [Formula: see text] at 95% C.L. in the hadronic channel. The corresponding results for the leptonic channel with [Formula: see text], 80% [Formula: see text] are [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text], [Formula: see text], respectively. The results for [Formula: see text] and [Formula: see text] in the leptonic channel are weaker than those corresponding to the hadronic channel by a factor of 0.75. Given these prospective sensitivities, the FCC-he is an alternative to study the anomalous couplings of the quark-top that would complement the studies of the LHC with cleaner environments.

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