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Absorption tabulated

Transition point is at higher potential than the tabulated formal potential because the molar absorptivity of the reduced form is very much greater than that of the oxidized form. [Pg.950]

Tables 2,3, and 4 outline many of the physical and thermodynamic properties ofpara- and normal hydrogen in the sohd, hquid, and gaseous states, respectively. Extensive tabulations of all the thermodynamic and transport properties hsted in these tables from the triple point to 3000 K and at 0.01—100 MPa (1—14,500 psi) are available (5,39). Additional properties, including accommodation coefficients, thermal diffusivity, virial coefficients, index of refraction, Joule-Thorns on coefficients, Prandti numbers, vapor pressures, infrared absorption, and heat transfer and thermal transpiration parameters are also available (5,40). Thermodynamic properties for hydrogen at 300—20,000 K and 10 Pa to 10.4 MPa (lO " -103 atm) (41) and transport properties at 1,000—30,000 K and 0.1—3.0 MPa (1—30 atm) (42) have been compiled. Enthalpy—entropy tabulations for hydrogen over the range 3—100,000 K and 0.001—101.3 MPa (0.01—1000 atm) have been made (43). Many physical properties for the other isotopes of hydrogen (deuterium and tritium) have also been compiled (44). Tables 2,3, and 4 outline many of the physical and thermodynamic properties ofpara- and normal hydrogen in the sohd, hquid, and gaseous states, respectively. Extensive tabulations of all the thermodynamic and transport properties hsted in these tables from the triple point to 3000 K and at 0.01—100 MPa (1—14,500 psi) are available (5,39). Additional properties, including accommodation coefficients, thermal diffusivity, virial coefficients, index of refraction, Joule-Thorns on coefficients, Prandti numbers, vapor pressures, infrared absorption, and heat transfer and thermal transpiration parameters are also available (5,40). Thermodynamic properties for hydrogen at 300—20,000 K and 10 Pa to 10.4 MPa (lO " -103 atm) (41) and transport properties at 1,000—30,000 K and 0.1—3.0 MPa (1—30 atm) (42) have been compiled. Enthalpy—entropy tabulations for hydrogen over the range 3—100,000 K and 0.001—101.3 MPa (0.01—1000 atm) have been made (43). Many physical properties for the other isotopes of hydrogen (deuterium and tritium) have also been compiled (44).
Uv—vis Spectra do not offer the unique group frequencies and fingerprinting abiUty of the it, but different chtomophotes exhibit absorptions at snecific wavelengths, A, and have characteristic intensities. These ate tabulated in handbooks as X and S, where S is a molar decadic absorption... [Pg.316]

Data on duorescence, phosphorescence, excited-state lifetimes, transient absorption spectra, and dye lasers are tabulated in Ref. 16. The main nonduorescent process in cyanine dyes is the radiationless deactivation Sj — Sg. Maximum singlet-triplet interconversion ( 52 ) methanol for carbocyanines is about 3% (maxLgrp > 0.03), and the sum [Lpj + st] I than 0.10. [Pg.398]

Henry s law is useful for handling equiUbria associated with gas absorption (qv) and stripping problems. Henry s law coefficients are useful for estimating terminal activity coefficients and have been tabulated for many compounds in dilute aqueous solutions (27). [Pg.158]

Effective wavelengths have been included in Table 3-1 to show the changes that occur in this important variable when one gas is substituted for another. These wavelengths correspond to mass absorption coefficients calculated from Equation 3-14 and were obtained by interpolation from tabulated values of absorption coefficients for different wavelengths.15... [Pg.83]

Only electric-dipole- and spin-allowed electronic transitions in the proximity of the observed transitions are tabulated. Anticipated overlap with atomic absorptions. [Pg.87]

The visible absorption maxima for a series of chlorinated dibenzo-p-dioxins in TFMS acid are tabulated in Table I. The visible absorption spectra of these compounds vary with the position and number of chlorine atoms. In general, a bathochromic shift was observed as more chlorine atoms were attached to the dibenzo-p-dioxin nucleus. [Pg.35]

The maximum absorption wavelengths in different solvents of many carotenoids can be found in the literature, and the % III/II values are also available for some carotenoids. It is common to find variations of 1 to 3 nm in for the same carotenoid in the same solvent cited in different publications. No identification based simply on the matching of recorded UV-Vis spectra with tabulated data can be done without considering the relationships of structures and the factors influencing light absorption. The principal factors that influence carotenoid UV-Vis absorption spectra are discussed below. [Pg.464]

The mass absorption coefficient used in (3.5)-(3.6) is obtained from tabulated mass absorption coefficients (given in cm g ) and the mass fractions Ci for the elements in the sample ... [Pg.50]

A UV analysis of the products formed upon photolysis of 2a at 280 nm in ethyl propionate, PMMA, and PPMA further illustrates the effect of the matrix stiffness on the photodecomposition process (Table III). The ratio 0C to b +, j [ c/( b+ d)) is determined by the ratio of absorbance of product 2c to the absorbances of products 2b and 2d [A2c/(A2b+A2d)1 n this case, since the results were tabulated from the actual absorption spectra (difference spectra), the ratio of the products formed in the solvent ethyl propionate can be directly compared to the ratios in PPMA and PMMA. From Table III, it is readily seen that the ratio increases on going from the ethyl propionate solution,... [Pg.125]

For all chemical elements, mass absorption coefficients p/p arc tabulated [13, 85] as a function of the X-ray wavelength. Chemical composition, mass density p, and thickness t of the sample are known. [Pg.98]

A different view of the OMT process is that the molecule, M, is fully reduced, M , or oxidized, M+, during the tunneling process [25, 26, 92-95]. In this picture a fully relaxed ion is formed in the junction. The absorption of a phonon (the creation of a vibrational excitation) then induces the ion to decay back to the neutral molecule with emission (or absorption) of an electron - which then completes tunneling through the barrier. For simplicity, the reduction case will be discussed in detail however, the oxidation arguments are similar. A transition of the type M + e —> M is conventionally described as formation of an electron affinity level. The most commonly used measure of condensed-phase electron affinity is the halfwave reduction potential measured in non-aqueous solvents, Ey2. Often these values are tabulated relative to the saturated calomel electrode (SCE). In order to correlate OMTS data with electrochemical potentials, we need them referenced to an electron in the vacuum state. That is, we need the potential for the half reaction ... [Pg.204]

Significant tabulations of spectra are available in hardcopy or in electronic databases. In addition, compilations of common absorption bands based on functional group or vibrational mode are also available. [Pg.127]

Fig. 4 Example of a ratiometric ICT probe (a) and representative spectroscopic responses toward Zn2+ (tabulated b), absorption (c), fluorescence (d). For color code and symbols, see Fig. 3. (Reprinted in part with permission from [56]. Copyright 2009 Elsevier)... Fig. 4 Example of a ratiometric ICT probe (a) and representative spectroscopic responses toward Zn2+ (tabulated b), absorption (c), fluorescence (d). For color code and symbols, see Fig. 3. (Reprinted in part with permission from [56]. Copyright 2009 Elsevier)...
Equation (8) therefore allows us to use directly tabulated subshell photo-ionization cross sections (p) instead of mass absorption coefficients (a). F is the integrated photoelectron signal from an appropriate subshell of the monolayer adatom Yg the integrated signal from the relevant subshell of the substrate which is not simply the area of the core-level peak p and p. [Pg.60]

Note on the use of data tables. Tabulated data typically give characteristic absorptions or chemical shifts for representative compounds and these may not correlate exactly with those from an unknown compound. The data contained in data tables should always be used indicatively (not mechanically). [Pg.87]

In Table I, the results of this experiment are compared to reflectance spectra measured for other simple and complex metal-TCNQ salts. We found that the CN stretching mode in reflectance measurements shifted to higher frequency by about 100 cm from absorption measurements made on the same material. The peak in the reflectance band at 2320 cm for the Cu-TCNQ film prior to the application of a field is consistent with the values measured for the simple (1 1) salts of Li+(TCNQ ) and Cu+(TCNQ") tabulated in Table I. These crystalline materials are simple salts which do not contain neutral TCNQ . On the other hand the spectra of a Cu-TCNQ film after the application of an applied field closely resembles the spectra of Cs2 (TCNQ [ )3 with two CN stretching modes separated by 20 cm. Cs2(TCNQ )3 is a complex salt which contains neutral TCNQ and radical-anion TCNQ . (11)... [Pg.242]

Some of the above-mentioned parameters are tabulated for a few carbon blacks of very different morphology (Table 4). It appears that, in spite of its complex morphology, the structure of a black can generally be fairly well evaluated knowing its specific surface area and its DBP absorption capacity (DBP number)16). [Pg.108]

Annelation on to a benzene ring increases considerably the complexity of the spectra, and indole has absorptions at 216 (4.54), 266 sh (3.76), 270 (3.77), 276 (3.76), 278 (3.76) and 287 (3.68) nm in ethanol solution. Because of the widespread occurrence of the indole ring system in nature and the sensitivity of absorption band position and intensity to substitution type, considerable use has been made of electronic spectroscopy in the past for structure identification. An extensive tabulation of data, primarily for monosubstituted derivatives, is available (71PMH(3)67,p.94). As expected, whereas the effects of alkylation are comparatively slight, introduction of groups capable of mesomeric interaction with the indole it -system may cause profound changes in the appearance of the spectrum representative examples are given in Table 24. [Pg.178]

Investigations of the electronic structure of quadruply bound dimers have relied heavily on electronic spectra to reveal the nature of the excited-state configurations. The availability of quantitative molecular orbital calculations coupled with single-crystal polarized electronic absorption spectral studies of quadruply bound dimers at low temperature has firmly established certain features of the excited electronic states of these compounds. A discussion of electronic spectra follows and a tabulation of energies associated with 6 - 6 transitions in quadruply bound dimers is given in Table 111. [Pg.253]


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See also in sourсe #XX -- [ Pg.497 , Pg.498 , Pg.499 ]




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