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Low-frequency losses in weakly anharmonic cubic centrosymmetric crystals as a function of permittivity are estimated using phonon kinetics approach. It is shown that very steep dependencies up to the fifth power of permittivity (epsilon'' is-proportional-t ...
Hydrogenated amorphous silicon has been prepared at a plasma excitation frequency in the very-high-frequency band at 70 MHz with the glow discharge technique at substrate temperatures between 280 and 50-degrees-C. The structural properties have been studie ...
One of the most important parameters in characterization of integrated optical devices is precise determination of the effective cut-off wavelength of the fundamental and first-order modes, since this sets the exact region of single-mode operation. This pa ...
It is now generally recognized that the excitation frequency is an important parameter in radio-frequency (rf) plasma-assisted deposition. Very-high-frequency (VHF) silane plasmas (50-100 MHz) have been shown to produce high quality amorphous silicon films ...
This method measures cross relaxation rates in highly resolving NMR spectroscopy, where the sample substance is dissolved in a liq. and has nuclei A and X which have different chem. shifts WA and WX in a homogeneous static magnetic field Bo in the directio ...
Some problems associated with sub-band coding of images are investigated. The filtering operations needed for splitting an input into different frequency bands, as well as their reconstruction, require an extension beyond the length of the finite signal. I ...
The authors present an analysis in the frequency domain of lightning electromagnetic fields making use of a computer code developed by the authors. The analysis is made for different distances from the lightning channel, for two different current waveshape ...
Material and temp. instabilities in autothermal reactors, e.g. catalyst temp. instabilities and steep radial and axial temp. profiles, and difficulty in isolation of intermediate products, are resolved by periodic operation of the reactor. Using the oxidn. ...