Dielectric Properties of Hydrogen Halides. III. High‐Frequency Dispersion in Solid Phases of HI and HBr

1967 ◽  
Vol 46 (3) ◽  
pp. 1069-1074 ◽  
Author(s):  
P. P. M. Groenewegen ◽  
R. H. Cole

The dielectric properties of aqueous solutions of the sodium salts of ribonucleic acid and deoxyribonucleic acid have been determined. The general pattern of behaviour observed for other aqueous polyelectrolyte systems has been verified in these studies. There are indications that a low frequency dispersion region (below 2 Mc/s) is present as well as the normal high frequency dispersion region. The theoretical interpretation of the experimental results makes use of the O’Konski theory of ionic polarization and the formulation of an equilibrium between counterions ‘non-specifically bound’ and ‘free’ from the electrostatic field of the polyion. Calculations are made on the basis of this theory and estimates of the values of the specific conductivities existing at the polyion surface are made.


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4017
Author(s):  
Dorota Szwagierczak ◽  
Beata Synkiewicz-Musialska ◽  
Jan Kulawik ◽  
Norbert Pałka

New ceramic materials based on two copper borates, CuB2O4 and Cu3B2O6, were prepared via solid state synthesis and sintering, and characterized as promising candidates for low dielectric permittivity substrates for very high frequency circuits. The sintering behavior, composition, microstructure, and dielectric properties of the ceramics were investigated using a heating microscope, X-ray diffractometry, scanning electron microscopy, energy dispersive spectroscopy, and terahertz time domain spectroscopy. The studies revealed a low dielectric permittivity of 5.1–6.7 and low dielectric loss in the frequency range 0.14–0.7 THz. The copper borate-based materials, owing to a low sintering temperature of 900–960 °C, are suitable for LTCC (low temperature cofired ceramics) applications.


2001 ◽  
Vol 674 ◽  
Author(s):  
M.I. Rosales ◽  
H. Montiel ◽  
R. Valenzuela

ABSTRACTAn investigation of the frequency behavior of polycrystalline ferrites is presented. It is shown that the low frequency dispersion (f < 10 MHz) of permeability is associated with the bulging of pinned domain walls, and has a mixed resonance-relaxation character, closer to the latter. It is also shown that there is a linear relationship between the magnetocrystalline anisotropy constant, K1, and the relaxation frequency. The slope of this correlation depends on the grain size. Such a relationship could allow the determination of this basic parameter from polycrystalline samples.


1977 ◽  
Vol 55 (11) ◽  
pp. 975-983 ◽  
Author(s):  
J. E. Vesel ◽  
B. H. Torrie

The ferroelectric and proposed paraelectric phases of the hydrogen halides have been studied using a lattice of molecules which are represented by a set of electric multipoles. This model shows the dominance of quadrupole–quadrupole interactions and the importance of other multipole interactions which affect the librational motions of these molecular crystals. A dynamic ferroelectric phase model was used to calculate the frequencies of the four librational modes.


Rare Metals ◽  
2015 ◽  
Vol 36 (3) ◽  
pp. 205-208 ◽  
Author(s):  
Ke-Lan Yan ◽  
Run-Hua Fan ◽  
Min Chen ◽  
Kai Sun ◽  
Xu-Ai Wang ◽  
...  

2021 ◽  
Vol 56 ◽  
pp. 97-107
Author(s):  
M. S. Zayats ◽  

A low-temperature (substrate heating temperature up to 400 °C) ion-plasma technology for the formation of nanostructured AlN and BN films by the method of high-frequency reactive magnetron sputtering of the corresponding targets has been developed (the modernized installation "Cathode-1M"), which has in its technological cycle the means of physical and chemical modification, which allow to purposefully control the phase composition, surface morphology, size and texture of nanocrystalline films. The possibility of using the method of high-frequency magnetron sputtering for deposition of transparent hexagonal BN films in the nanoscale state on quartz and silicon substrates is shown. Atomic force microscopy (AFM) has shown that AlN films can have an amorphous or polycrystalline surface with grain sizes of approximately 20-100 nm, with the height of the nanoparticles varying from 3 to 10 nm and the degree of surface roughness from 1 to 10 nm. It was found that the dielectric penetration of polycrystalline AlN films decreases from 10 to 3.5 at increased frequencies from 25 Hz to 1 MHz, and the peak tangent of the dielectric loss angle reaches 0.2 at 10 kHz. Such features indicate the existence of spontaneous polarization of dipoles in the obtained AlN films. Interest in dielectric properties in AlN / Si structures it is also due to the fact that there are point defects, such as nitrogen vacancies and silicon atoms, which diffuse from the silicon substrate during synthesis and play an important role in the dielectric properties of AlN during the formation of dipoles. The technology makes it possible, in a single technological cycle, to produce multilayer structures modified for specific functional tasks with specified characteristics necessary for the manufacture of modern electronics, optoelectronics and sensorics devices. It should also be noted that the technology of magnetron sputtering (installation "Cathode-1M") is highly productive, energetically efficient and environmentally friendly in comparison with other known technologies for creating semiconductor structures and allows them to be obtained with minimal changes in the technological cycle.


1968 ◽  
Vol 39 (1) ◽  
pp. 70-74 ◽  
Author(s):  
Robert T. Smith ◽  
Gary D. Achenbach ◽  
Robert Gerson ◽  
W. J. James

1996 ◽  
Vol 54 (2) ◽  
pp. 1568-1586 ◽  
Author(s):  
Steven Corley ◽  
Ted Jacobson

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