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Scattering cross section temperature

Beryllium has a high x-ray permeabiUty approximately seventeen times greater than that of aluminum. Natural beryUium contains 100% of the Be isotope. The principal isotopes and respective half-life are Be, 0.4 s Be, 53 d Be, 10 5 Be, stable Be, 2.5 x 10 yr. Beryllium can serve as a neutron source through either the (Oi,n) or (n,2n) reactions. Beryllium has alow (9 x 10 ° m°) absorption cross-section and a high (6 x 10 ° m°) scatter cross-section for thermal neutrons making it useful as a moderator and reflector in nuclear reactors (qv). Such appHcation has been limited, however, because of gas-producing reactions and the reactivity of beryUium toward high temperature water. [Pg.66]

Figures 8 and 9 shows a part of the bending region at low temperature containing the components of Vg (150-160 cm ) and Vs (190-200 cm ). The Vg vibration, IR active in the free molecule, has weak components in the Raman spectrum. According to theoretically calculated Raman intensities, which almost perfectly fit the experimental spectrum, the big component has a very low scattering cross-section [87] and is accidentally degenerate with the b2g component at ca. 188 cm. The IR active components of Vg cause strong absorptions in the IR spectrum even if the crystalline sample used for transmission studies is as thin as 400 pm [107, 109]. Figures 8 and 9 shows a part of the bending region at low temperature containing the components of Vg (150-160 cm ) and Vs (190-200 cm ). The Vg vibration, IR active in the free molecule, has weak components in the Raman spectrum. According to theoretically calculated Raman intensities, which almost perfectly fit the experimental spectrum, the big component has a very low scattering cross-section [87] and is accidentally degenerate with the b2g component at ca. 188 cm. The IR active components of Vg cause strong absorptions in the IR spectrum even if the crystalline sample used for transmission studies is as thin as 400 pm [107, 109].
FIGURE 8.21 Comparison of the radial profiles for scattering cross-section gvv and temperature (uncorrected) as a function of radial position for a coannular ethane diffusion flame (from Santoro et al. [85]). [Pg.477]

Figure 3.15 (Heeger 1969, p. 306) shows the added resistivity due to iron-group impurities in gold. The low-temperature values, for which scattering cross-sections of order a2 occur (the unitarity limit ), include Kondo scattering. At room temperature, kBT is too great for most of the electrons near E to resonate... Figure 3.15 (Heeger 1969, p. 306) shows the added resistivity due to iron-group impurities in gold. The low-temperature values, for which scattering cross-sections of order a2 occur (the unitarity limit ), include Kondo scattering. At room temperature, kBT is too great for most of the electrons near E to resonate...
The temperature dependences of the small-angle neutron scattering (SANS) from solutions and networks of poly(N,N -diethylacrylamide) or from copolymer of DEAAm and MNa (xMNa = 0.05) in deuterated water were measured [41]. Experimental dependences of the effective scattering cross-section... [Pg.200]

The profiles of the actinic flux are computed at each grid point of the model domain. To determine the absorption and scattering cross sections needed by the radiative transfer model, predicted values of temperature, ozone, and cloud liquid water content are used below the upper boundary of WRF. Above the upper boundary of WRF, fixed typical temperamre and ozone profiles are used to determine the absorption and scattering cross sections. These ozone profiles are scaled... [Pg.43]

Another intriguing quality of Raman spectroscopy is its capability to measure local temperature quantitatively and precisely. This is possible in two distinct ways, arising due to two different characteristics of the Raman spectra in crystalline solids. The first characteristic is the presence of the phonon occupation number in the Raman scattering cross section in accordance with (17.3). While the relation to temperature of the strict intensity of a particular phonon peak is obfuscated by the numerous other components of the Raman scattering cross section, taking the ratio of integrated intensities of the Stokes (1 ) and anti-Stokes (Ias) peaks provides the following relationship by which to measure temperature ... [Pg.500]


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Scattering cross section temperature dependence

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