Vs band

Figure 3. Sky coverage of an adaptive optics at an 8m telescope. Pupil sampling by the actuators of the deformable mirror 0,5m, 0 = 0,17m, From top to bottom in a direction of galactic latitude 6 = Of (the Milky Way), b = 20f and b = 90f (the galactic pole). From left to right K, 1 and V bands.

Figure 29. Maximum Strehl ratio versus return flux above atmosphere at 330 nin at an 8in telescope. Top to bottom tilt correction in K,, 1 and V bands. Solid, dashed and dotted lines ro 15, 20 cm and 25 cm. (Schbek ct al., 2002).

An analysis of the Fourier Transform i.r. spectrum of PF around 946 cm-1 gave rise to nine spectroscopic constants for the Vg band and five for the Vg + v -v band which allowed calculation of the wavenumbers of the Vg band with a precision of 1 x 10-3 cm-1.11... 

Fig. 8. Theoretical simulation of VCD (top) and IR absorption (bottom) spectra of alanine dodecapeptides for the amide V bands for a fully a-helical conformation (left) and a fully left-handed 3i-helical conformation (right). The simulations are for the same three isotopically labeled (13C on the amide C=0 for four Ala residues selected in sequence) peptides as in Figure 7 N-terminal tetrad (4AL1), middle (4AL2), and C-terminal (4AL4). The 13C feature is the same for all sequences, confirming the experimentally found unfolding of the C-terminus. The agreement with the shapes in Figure 7 is near quantitative. Reprinted from Silva, R. A. G. D., Kubelka, J., Decatur, S. M., Bour, R, and Keiderling, T. A. (2000a). Proc. Natl. Acad. Sci. USA 97, 8318-8323. 2000 National Academy of Science, U.S.A.

We have determined the iron abundances for a sub-sample of stars 13 Galactic, 13 LMC and 12 SMC Cepheids. Our main result is summarised in the Fig.l, where we plot the V-band residuals 5(My) of our stars from the standard PL relation of [3] as a function of the iron abundance we have derived from the... 

A set of SER spectra for adsorbed azide on silver, obtained for the same surface and solution conditions and for a similar sequence of electrode potentials as for the PDIR spectra in Figure 1, is shown in Figure 2. (See the figure caption and reference 7 for experimental details.) Inspection of these SER spectra in comparison with the PDIR results illustrate some characteristic differences in the information provided by the two techniques. Most prominently, in addition to the Nj" j/as band around 2060 cm"1, the former spectra exhibit three other features at lower frequencies attributable to adsorbed azide vibrations. By analogy with bulk-phase spectra for free and coordinated azide (15), the 1330 cm"1 SERS band is attributed to the N-N-N symmetric stretch, vt (2). The observation of both i/a and j/aa features in the SER spectra differs from the surface infrared results in that only the v band is obtained in the latter (2). The appearance of the vn band in SERS is of interest since this feature is symmetry forbidden in the solution azide Raman spectrum. 

V band spect Absorption bands that appear in the ultraviolet part of the spectrum due to color centers produced in potassium bromide by exposure of the crystal at temperature of liquid nitrogen (81 K) to intense penetrating x-rays. ve. band ( vcp See vacuum condensing point. 

Fukazawa, T., S. Miyake, V. Band, and H. Band. Tyrosine phosphorylation of Cbl upon epidermal growth factor (EGF) stimulation and its association with EGF receptor and downstream signaling proteins. J Biol Chem. 271 14554-14559.1996. 

The electronic absorption spectrum of nickelocene has been recorded and analyzed in considerable detail by Scott and Becker.11 They found band maxima at 1920, 3075, and 6920 A and shoulders at 2700, 3450, 4400, and 5700 A. The band at 1920 A is believed to be an allowed transition which is designated as a W-F transition in ferrocene, but the intensity of this band is less than the N-V band in ferrocene. The shoulder at 2700 A is denoted as a N-Vor N-Q transition similar to the 2300 and 2600 A shoulders in ferrocene. The band at 3075 A is relatively intense and occurs at approximately the same wavelength as the intermolecular charge transfer band of ferrocene in carbon tetrachloride described by Brand and Snedden. The absorption spectrum of nickelocene in carbon tetrachloride shows no new bands other than those found in cyclohexane or ethanol. 

Fig. 1. Representation of the band structure of GaAs, a prototypical direct band gap semiconductor. Electron energy, E> is usually measured in electron volts relative to the valence, v, band maximum which is used as the zero reference. Crystal momentum, k, is in the first Brillouin zone in units of 2%/a...

It is well known that the v, band of liquid acetonitrile is significantly asymmetric due to an overlap of hot band transitions in the low frequency side. A study of gas phase rotation-vibration spectrum [19] showed that the hot band transition from the first exited state of the degenerated C-C = N bending v8 mode, v hl = v + v8 - vs, has its center at 4.944 cm 1 lower than that of the fundamental transition, v,. Also the presence of v,h2 = v, + 2v8 - 2v8 transition is expected. The careful study on the v band of liquid acetonitrile by Hashimoto et al [20] provided the reorientational and vibrational relaxation times of liquid acetonitrile molecule. They corrected the contribution by the hot band transition using the Boltzmann population law and approximated the v , v,hl, 2h2, and v, + v4 bands by Lorentzian curves. 

In the CD spectrum of (+)-flavanone (193), the n ->v band is negative proving its absolute configuration to be 2R (73T909). The majority of naturally occurring 3-hydroxy-2-phenylchroman-4-ones have the configuration 2R,3R. This area has been briefly discussed (B-75MI22201). 

Ethylamine Solutions, (a) Photoregeneration of Bleached Solutions—The absorption spectra of alkali metals in ethylamine have been discussed in previous publications (24,25). Briefly, three characteristic bands are found, absorbing at about 650 (V), 850 (R) and 1300 (IR) m/z, and attributed respectively to metal monomers, dimers, and solvated electrons. In potassium solutions, the equilibria favor the V-band, while in rubidium the R-band is most prominent, except at extreme dilutions. 

We therefore conclude that no directly formed precursor of the V-band is seen in our experiments, and the photoregeneration reaction must occur in times shorter than the flash duration (3 /zsec). 

Reversible bleaching experiments, in which the R-band decays to form the V-band, give a ratio of AZ>85o/AZ>65o = 0.92 at —78° C. Assuming that this is a dimer - monomer conversion, we thus obtain R-band = (4.9 X 104) (2) (0.92) = (9.0 it 2) X 104, for the molar extinction coefficient of the dimer at its absorption peak, at — 78 ° C. Table II summarizes these values and corresponding exinction coefficients in ammonia. 

Other mixed vibration bands known as the amide III, IV and V bands have been identified in various regions of the spectrum but they are of limited diagnostic value. 

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