Wavelength tabulated

Wavelengths tabulated normally refer to the pure element in its solid form. However, there are many instances in which such data are not available. For example, rare gases are of necessity almost always used in the gaseous form, while the rare-earth elements were customarily used in the form of salts. 

For times below about 5 msec a correction must be made to allow for the fact that the surface velocity of the liquid in the nozzle is zero and takes several wavelengths to increase to the jet velocity after emerging from the nozzle. Correction factors have been tabulated [107, 108] see also Ref. 109. 

Fowlef measured the turbidity of air at Mt. Wilson, California, on a clear day in 1913. Values of rx for dry air at different wavelengths are tabulated below, where x is essentially the thickness of the atmosphere corrected to standard temperature and pressure (STP) conditions ... 

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... 

The correction factor C still applies. Spectral data for water vapor, tabulated for 371 wavelength intervals from 1 to 40 Im, are also available [Ferriso, Ludwig, and Thompson, J. Quant. Spectm.s. Radiat. Tran.sfer, 6, 241-273 (1966)]. The principal emission is in bands at about 2.55 to 2.84, 5.6 to 7.6, and 12 to 25 jlm. 

The conversion of radiated power (P in watts) to luminous flux (F in lumens) is achieved by considering the variation with wavelength of the human eye s photopie response. Then the spectral power from the source (PA in, lor example, W/nnt) is convoluted with the relative spectral response of the eye (V tabulated by the CIE) according to ... 

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... 

Values of K have been tabulated for particles of various diameters. For extremely small particles K is nearly zero. Its value increases rapidly to between 3 and 5 for particles in the range of approx 0.3 to 0.7 microns. As the size of the particle increases, K drops to a constant value of 2. When values of K are known, and when either the particle diameter or the number of particles is known, the other may be determined from the ratio It/I0. If both n and r are unknown, they may be determined by making transmission measurements at two different wavelengths and setting up simultaneous equations using equation (16)... 

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. 

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. 

Hamaker constants can sometimes be calculated from refractive igdex data by the Lifshitz equations (8), but it now appears that Y values are closely related to refractive indices and are a direct measure of the Lifshitz attractions. In Equation 1 a correction factor f for "retardation" of dispersion forces is shown which can be determined from Figure 2, a graph of 1/f at various values of H and a as a function of Xj, the characteristic wavelength of the most energetic dispersion forces, calculable and tabulated in the literature (9). 

The characteristic X-ray wavelengths are tabulated in all standard texts on X-ray spectrometry, but can also be calculated from the atomic number of the element by Moseley s law ... 

As indicated, the specific refractive index increment is best measured by differential refractometry or interferometry. Experimental procedures as well as tabulated values of dn/ dc for many systems have been presented elsewhere40,63K The relevant wavelength and temperature are those used for LS. The value of X0 is invariably 436 or 546 nm, but with the advent of laser LS, values of dn/dc at other wavelengths are required. These can be estimated with good reliability using a Cauchy type of dispersion (dn/dc a 1/Xq). For example the values of dn dc for aqueous solutions of the bacterium T-ferrioxidans at 18 °C are 0.159, 0.141 and 0.125 ml/gm at X0 = 488, 633 and 1060 nm respectively64 ... 

Previous experience in arc and spark emission spectroscopy has revealed numerous spectral overlap problems. Wavelength tables exist that tabulate spectral emission lines and relative intensities for the purpose of facilitating wavelength selection. Although the spectral interference information available from arc and spark spectroscopy is extremely useful, the information is not sufficient to avoid all ICP spectral interferences. ICP spectra differ from arc and spark emission spectra because the line intensities are not directly comparable. As of yet, there is no atlas of ICP emission line intensity data, that would facilitate line selection based upon element concentrations, intensity ratios and spectral band pass. This is indeed unfortunate because the ICP instrumentation is now capable of precise and easily duplicated intensity measurements. 

Catalog of Infrared Spectrograms. Philadelphia Sadtler Research Laboratories, PA. 19104. Spectra are indexed by name and by the Spec-Finder. The latter is an index that tabulates major bands by wavelength intervals. This allows quick identification of unknown compounds. 

The EPA s GC-SOLAR computer model (EPA, 1982) estimates values of Ilight flux terms called Zx with units of photons cm-2 s-1. Zepp and Cline (1977) tabulated Zx values for mid-day and mid-season at 40°L. GC-SOLAR provides the most reliable method for estimating photolysis rates corresponding to half lives of a few minutes to a few hours. 

Equation (11) estimates sunlight photoreaction rate constants using computed or tabulated values for Zk or tabulated values of L> at the appropriate latitude and time of year (Zepp and Cline, 1977 Mill and Mabey, 1985 Leifer, 1988), together with measured values of > and <1>. Equation (2) can be used to estimate values of > from a uv spectrum measured in water or, if aqueous solubility is low, a polar organic solvent such as acetonitrile or methanol. Absorbance values are converted into ex values at wavelength centers corresponding to those Table 15.1 lists. 

The values of Fov are found from referenced ) at the wavelengths or frequencies at which Ivr values are tabulated. These values are summarized in Table A. 

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