Crystals high frequency

Use (Unstabilized) Production of piezoelectric crystals, high-frequency induction coils, colored ceramic glazes, special glasses, source of zirconium metal, heat-resistant fibers, (hydrous) odor absorbent, to cure dermatitis caused by poison ivy. (Stabilized with CaO refractory furnace linings, crucibles, solid electrolyte for batteries operating at high temperature. 

As is well known, the recoil-free fraction of very small crystals differs markedly from that of bulk material. Roth and Horl [236] observed a decrease of the/-factor from 0.61 to 0.57 in going from 1 p,m crystals to microcrystals with a diameter of about 60 A. Two effects will contribute to this decrease (1) the low frequency cutoff, because the longest wavelength must not exceed the dimensions of the crystal, and (2) high frequency cut-off caused by the weaker bonds between surface atoms. 

To reduce the high frequency noise of Fig. 16.9, and also to minimize low frequency vibrations of the tower, the crystal copper frame has been mechanically decoupled from the cryostat. 

Cu(acacen) diluted into Ni(acacen) 1/2 H20 has been chosen as a typical example to demonstrate the separation of magnetically nonequivalent sites in a single crystal by proton EI-EPR. For the specific orientation shown in Fig. 14, the ordinary EPR spectrum of site II is difficult to analyze (Fig. 14 a). In the corresponding EI-EPR spectrum (Fig. 14 b), a high-frequency proton ENDOR line of this site has been used as an observer. Since site I is completely suppressed in the EI-EPR spectrum, the analysis of the hf data of site II becomes straightforward. 

Figure 7. Librational infrared spectra of methanol clusters [93] (bands B and C due to the tetramer, broad profile due to large clusters, cluster size increases from bottom to top) compared to the absorptions in amorphous and crystalline (zig zag) solid methanol [40]. The large clusters compare well to the amorphous solid, whereas the ring tetramer may be viewed as a small model of the zig zag chains in the crystal. Note that the high frequency band C acquires IR intensity through puckering of the methyl groups above (u) and below (d) the hydrogen bond plane.

The basis for the present-day generation of ultrasound was established as far back as 1880 with the discovery of the piezoelectric effect by the Curies [1-3]. Most modern ultrasonic devices rely on transducers (energy converters) which are composed of piezoelectric material. Such materials respond to the application of an electrical potential across opposite faces with a small change in dimension. This is the inverse of the piezoelectric effect and will be dealt with in detail later (Chapter 7). If the potential is alternated at high frequencies the crystal converts the electrical energy to mechanical... 

For low coating rates, small densities of the coating material and fast measurements (that require short counting times), it is important to have a reference oscillator with a high frequency. All of this requires great time precision so that the small coating-related frequency shifts can be resolved. If the frequency shift of the monitor crystal decreases between two... 

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