Frequency electric permitivities

Spinel ferrites, isostmctural with the mineral spinel [1302-67-6] MgAl204, combine interesting soft magnetic properties with a relatively high electrical resistivity. The latter permits low eddy current losses in a-c appHcations, and based on this feature spinel ferrites have largely replaced the iron-based core materials in the r-f range. The main representatives are MnZn-ferrites (frequencies up to about 1 MH2) and NiZn-ferrites (frequencies 1 MHz). 

Electrical Properties. Polysulfones offer excellent electrical insulative capabiUties and other electrical properties as can be seen from the data in Table 7. The resins exhibit low dielectric constants and dissipation factors even in the GH2 (microwave) frequency range. This performance is retained over a wide temperature range and has permitted appHcations such as printed wiring board substrates, electronic connectors, lighting sockets, business machine components, and automotive fuse housings, to name a few. The desirable electrical properties along with the inherent flame retardancy of polysulfones make these polymers prime candidates in many high temperature electrical and electronic appHcations. 

It has become recognized during recent years that the color of dyes is associated with the resonance of electric charge from atom to atom of the dye molecule.2,3> 4 6 6 Because of the complexity of the problem, however, it has not been easy to expand this idea into a theory of color permitting the rough quantitative calculation of the frequencies and intensities of the absorption bands of dyes. I have now developed a theory of this nature the theory and some of the results of its application are described briefly in the following paragraphs. 

Normally an oscillator circuit Is designed such that the crystal requires a phase shift of 0 degrees to permit work at the series resonance point. Long-and short-term frequency stability are properties of crystal oscillators because very small frequency differences are needed to maintain the phase shift necessary for the oscillation. The frequency stability Is ensured through the quartz crystal, even If there are long-term shifts In the electrical values that are caused by phase jitter due to temperature, ageing or short-term noise. If mass Is added to the crystal. Its electrical properties change. 

In the quadrupole mass analyzer, focusing electrodes direct and accelerate the ionized fragments into a mass filter consisting of four cylindrical electrodes in a vacuum. Tire cylindrical electrodes establish a combination radio-frequency and direct-current electrical field that permits only those ions with a specific, selected mass-to-charge ratio to pass all the way through the filter. The rest of the ions impact die electrodes and do not travel to the exit. Varying the electrical field allows ions with other masses to pass through the filter. 

The hyperbolic cell offers several advantages for accurate mass determinations. 1) The frequencies of fundamental modes of the ion motion are independent of the location of the ion in the cell at least for the low ion limit. This is important because frequencies are known to be influenced by the location of the ions in cubic cells. 2) The excitation electric field has a simple form identical to that of the trapping field. Thus, the operation of the trap is the same everywhere in the interior permitting most of the volume to be used for storage of larger ion populations with reduced space charge effects. 3) Harmonic effects (31,13b) that complicate spectra are removed. 

The molecular lever mechanisms that permit muscle function to directly regulate the genomic activity of strained bone cells, including their phenotypic expression, when combined together with electric field effects and contraction frequency energetics, provides a biophysical basis for an earlier hypothesis of epigenetic regulation of skeletal tissue adaptation [135, 136, 146, 147]. 

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