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Vibrational susceptibility

The expression for the vibration susceptibility is analogous to Eq. (281a) but we should cancel the optical permittivity n2, since it was included into the term Xor-Hence,... [Pg.226]

ISO 10814 Mechanical vibration - Susceptibility and sensitivity of machines to unbalances. [Pg.1698]

Bellows can vibrate, both from internal fluid flow and externally imposed mechanical vibrations. Internal flow liner sleeves prevent flow-induced resonance, which produces bellows fatigue failure in minutes at high flow velocities. Mechanically induced resonant vibration is avoided by a bellows with a natural frequency far away from the forcing frequency, if known. Multiple-ply bellows are less susceptible to vibration failure because of the damping effect of interply friction. [Pg.66]

By dynamically balancing most parts, seal life and bearing life is greatly improved, even on smaller equipment. Dynamic balancing is needed on pump impellers, as the practice of static balance is woefully inadequate. Vertical pumps must be dynamically balanced the long, slender shafts are highly susceptible to any unbalanced-induced vibration. [Pg.736]

The rotating type may be driven from either the top or the bottom whilst the vibrating type is always driven from the top. The removal of the tank head cover from top driven filters is generally more complex than those driven from the bottom. On the other hand bottom driven filters are more susceptible to slurry leaks. The position of the cake outlet depends on the construction of the tank bottom. There are two types available ... [Pg.194]

This report provides an aging assessment of electric motors and was conducted under the auspices of the USNRC NPAR. Pertinent failure-related information was derived from LERs, IPRDS, NPRDS, and NPE including failure modes, mechanisms, and causes for motor problems. In addition, motor design and materials of construction were reviewed to identify age-sensitive components. The study included consideration of the seismic susceptibility of age-degraded motor components to externally-induced vibrational effects. [Pg.98]

Measurements. Infra-red spectra for the region 600-4000 cm-1 were measured with a Perkin-Elmer Model 710B spectrometer on samples pressed in KBr pellets. Magnetic susceptibilities were measured with a vibrating sample magnetometer (Princeton Applied Physics) as previously described.(4)... [Pg.47]

Special Problems Reflection Losses Result in Low Optical Throughput Limiting Signal to Noise Highly Susceptible to Airborne Noise and Build-inq Vibrations... [Pg.451]

Spin-state transitions have been studied by the application of numerous physical techniques such as the measurement of magnetic susceptibility, optical and vibrational spectroscopy, the Fe-Mbssbauer effect, EPR, NMR, and EXAFS spectroscopy, the measurement of heat capacity, and others. Most of these studies have been adequately reviewed. The somewhat older surveys [3, 19] cover the complete field of spin-state transitions. Several more recent review articles [20, 21, 22, 23, 24, 25] have been devoted exclusively to spin-state transitions in compounds of iron(II). Two reviews [26, 27] have considered inter alia the available theoretical models of spin-state transitions. Of particular interest is the determination of the X-ray crystal structures of spin transition compounds at two or more temperatures thus approaching the structures of the pure HS and LS electronic isomers. A recent survey [6] concentrates particularly on these studies. [Pg.58]

Embrittlement of service materials. The low temperatures inside storage tanks and transmission pipelines may cause significant susceptibleness of the structural material in vibrations and shocks. Mild steel and most iron alloys, at LH2 temperatures, lose their ductility being liable to increased risk of mechanical failure [50]. [Pg.551]

Summary. Coherent optical phonons are the lattice atoms vibrating in phase with each other over a macroscopic spatial region. With sub-10 fs laser pulses, one can impulsively excite the coherent phonons of a frequency up to 50THz, and detect them optically as a periodic modulation of electric susceptibility. The generation and relaxation processes depend critically on the coupling of the phonon mode to photoexcited electrons. Real-time observation of coherent phonons can thus offer crucial insight into the dynamic nature of the coupling, especially in extremely nonequilibrium conditions under intense photoexcitation. [Pg.23]

Let us consider a difficult example of sampling of mined materials (sand, dolomite, and limestone) used for the manufacture of glass. The materials are delivered in railroad cars each may contain up to 2 tons of material and are susceptible to vertical separation on the basis of size and density of particles because of vibrations during transportation [8]. To obtain a representative sample, sampling is done with a hollow... [Pg.25]

The red PL band of PS can not only be excited by above bandgap photons, but also by an intense IR (1064 nm) pulse [Di6]. Such a thermostimulated luminescence is known for the case of glasses. This observation was attributed to PS having about 100 times the third-order nonlinear optical susceptibility of bulk Si, as discussed in Section 7.3. Multiphoton excitation of the red PL band by resonant pumping of the vibrational modes of surface groups like Si-O [Di4] or Si-H [Ch8] provided evidence for excitation modes that involve the porous skeleton surface. [Pg.145]

Most of the four above-mentioned properties for Raman spectra can be explained by using a simple classical model. When the crystal is subjected to the oscillating electric field = fioc " of the incident electromagnetic radiation, it becomes polarized. In the linear approximation, the induced electric polarization in any specific direction is given by Pj = XjkEk, where Xjk is the susceptibility tensor. As for other physical properties of the crystal, the susceptibility becomes altered because the atoms in the solid are vibrating periodically around equilibrium positions. Thus, for a particular... [Pg.30]


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Vibrational susceptibility model

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