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Doppler dispersion

Keywords SBR STAP earth rotation range ambiguity crab angle crab magnitude Doppler dispersion range dependency waveform diversity Doppler warping. [Pg.190]

Doppler dispersion for transmitter frequency of 2380 MHz (kl3 cm). The product of the dispersions in delay and Doppler is the overspread factor at 2380 MHz. [Pg.221]

The Doppler meter may be used wherever small particulate solids, bubbles or droplets are dispersed in the fluid and are moving at essentially the same velocity as the fluid stream which is to be metered. A continuous ultrasonic wave is transmitted, again at an acute angle to the wall of the duct, and the shift in frequency between the transmitted and scattered waves is measured. This method of measurement of flowrate is frequently used for slurries and dispersions which present considerable difficulties when other methods are used. [Pg.267]

To sum up, the basic idea of the Doppler-selected TOF technique is to cast the differential cross-section S ajdv3 in a Cartesian coordinate, and to combine three dispersion techniques with each independently applied along one of the three Cartesian axes. As both the Doppler-shift (vz) and ion velocity (vy) measurements are essentially in the center-of-mass frame, and the (i j-componcnl, associated with the center-of-mass velocity vector can be made small and be largely compensated for by a slight shift in the location of the slit, the measured quantity in the Doppler-selected TOF approach represents directly the center-of-mass differential cross-section in terms of per velocity volume element in a Cartesian coordinate, d3a/dvxdvydvz. As such, the transformation of the raw data to the desired doubly differential cross-section becomes exceedingly simple and direct, Eq. (11). [Pg.11]

The zeta potential of the formulations was determined by Doppler velocimetry and PCS on a Zetasizer 4 (Malvern Instruments, U.K.), without further dilution. The zeta potential of LC-AmB under these conditions was —44 mV, slightly lower than that measured for the same lipid composition without AmB, —55 mV, but remaining consistent with colloidal stability. This reduction in the absolute value of the zeta potential could be due to the presence of AmB at the surface, because free AmB dispersed in water under the same conditions had a less negative zeta potential about —27 mV. [Pg.98]

In Chapter 2, Jansson describes the determination of the system response function for a dispersive spectrometer system. We have made a number of such determinations using very-low-pressure samples of, for example, CO in the 5-fim region. As discussed by Jansson, one records the data and then removes the Doppler profile using deconvolution, yielding the system response function. [Pg.179]

Spray Dynamic Structure. Detailed measurements of spray dynamic parameters are necessary to understand the process of droplet dispersion. Improvements in phase Doppler particle analyzers (PDPA) permit in situ measurements of droplet size, velocity, number density, and liquid flux, as well as detailed turbulence characteristics for very small regions within the spray. [Pg.1535]

Some very important surface properties of solids can be properly characterized only by certain wet chemical techniques, some of which are currently under rapid improvement. Studies of adsorption from solution allow determination of the surface density of adsorbing sites, and the characterization of the surface forces involved (the energy of dispersion forces, the strength of acidic or basic sites and the surface density of coul-ombic charge). Adsorption studies can now be extended with some newer spectroscopic tools (Fourier-transform infra-red spectroscopy, laser Raman spectroscopy, and solid NMR spectroscopy), as well as convenient modern versions of older techniques (Doppler electrophoresis, flow microcalorimetry, and automated ellipsometry). [Pg.69]

Figure 3.9 Doppler broadening. For a typical colloidal dispersion, Aw1/2 103 with... Figure 3.9 Doppler broadening. For a typical colloidal dispersion, Aw1/2 103 with...
An interesting modification of this technique is the fibre-optic dynamic anemometer (FODA)143. A length of fibre-optic cable carries the laser beam to the interior of the dispersion. Back-scattered light, with its Doppler frequency shift, is returned to the detector along with reflected light and, again, the resulting beat frequency pattern is analysed. Since only a very small volume around... [Pg.62]

This procedure has been used to determine droplet size in sprays. Oseillations in the curve relating x and D can be smoothed out by the use of an incident laser beam having a broad speetral bandwidth [83]. An accumulation of independent scattering intensities from multiple scatterers ean be used to measure the mean droplet size of a group [84]. This procedure has been applied to water sprays and the experimental data confirmed by phase Doppler anemometry [85]. The applicability of the polarization ratio technique is strongly influenced by the complex refractive index of the dispersed media and is limited to media having a relative refractive index below about 1.44 [86]. [Pg.538]


See other pages where Doppler dispersion is mentioned: [Pg.190]    [Pg.190]    [Pg.45]    [Pg.321]    [Pg.331]    [Pg.38]    [Pg.5]    [Pg.13]    [Pg.194]    [Pg.343]    [Pg.691]    [Pg.784]    [Pg.135]    [Pg.73]    [Pg.116]    [Pg.161]    [Pg.178]    [Pg.258]    [Pg.2322]    [Pg.121]    [Pg.381]    [Pg.91]    [Pg.195]    [Pg.45]    [Pg.118]    [Pg.711]    [Pg.321]    [Pg.331]    [Pg.283]    [Pg.283]    [Pg.283]    [Pg.283]    [Pg.118]    [Pg.711]    [Pg.102]   
See also in sourсe #XX -- [ Pg.190 ]




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