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Spectroscopic signals, combined analysis

Combined Analysis of Impedance and Modulation Spectroscopic Signals... [Pg.79]

The refined method of analysis of co-dependent ER signal data set to obtain described in the last part of the previous section is in principle the combined use of ac impedance and the modulated spectroscopic signal. A similar calculation was reported by Yamada and Finklea and their colleagues [21, 71]. We describe below in detail the procedure for a concerted use of these two potential modulation techniques in the kinetic analysis. [Pg.79]

In the past decade several projects contributed to the luminosity distance measurements and by now (i.e., as of 2009) the list includes over 200 events. Specifically with the help of the Hubble telescope 13 new Sn la were found with spectroscopically confirmed redshifts exceeding z = 1 and at present the full sample contains already 23 z > 1 objects (Riess et al. 2007). Such objects most strongly influence the value of the deceleration parameter. A combined analysis of all Sn la data yields a deceleration parameter value of —0.7 0.1 (Kowalski et al. 2008). Its negative value signals an accelerating expansion rate at distance scales comparable to the size of the Universe. [Pg.623]

Fiber-optic biosensors are analytical devices in which a fiber optic device serves as a transduction element. The usual aim of fiber-optic biosensors is to produce a signal proportional to the concentration of target analyte to which the biological element reacts. Fiber-optic biosensors are based on the transmission of light along silica glass fiber, or POF to the site of analysis. They can be used in combination with different types of spectroscopic technique, e.g. absorption, fluorescence, phosphorescence, or surface plasmon resonance (SPR) (14). [Pg.185]

The first reliable spectroscopic analysis of saturated sulfur vapor was published by Berkowitz and Marquart [28] who used a combination of a Knud-sen effusion cell with a mass spectrometer and generated the sulfur vapor by evaporating either elemental sulfur (low temperature region) or certain metal sulfides such as HgS which decompose at high temperatures to sulfur and metal vapor. These authors observed ions for all molecules from S2 to Ss and even weak signals for Sg and Sio. From the temperature dependence of the ion intensities the reaction enthalpies for the various equilibria (1) were derived (see Table 1). Berkowitz and Marquart careMly analyzed their data to minimize the influence of fragmentation processes in the ion source of the spectrometer. They also calculated the total pressure of sulfur vapor from their data and compared the results with the vapor pressure measurements by Braune et al. [26]. The agreement is quite satisfactory but it probably... [Pg.119]

One important use of SFG vibrational spectroscopy is the orientational analysis of ionic liquids at gas-liquid interfaces. For example, the study of the structural orientation ofionic liquids using common cation types, that is, [BMIM], combined with different anions, gives information on the effects of both cation and anion types [3, 22, 26-28]. Additional surface analytical work includes SFG studies under vacuum conditions for probing the second-order susceptibility tensor that depends on the polar orientation of the molecule and can be correlated to the measured SFG signal intensities. Supporting information is frequently obtained by complementary bulk spectroscopic techniques, such as Raman and Fourier transform infrared (FTIR) analysis, for the analysis of the pure ionic liquids. [Pg.148]

Assignments of intensities and calculation of concentrations can be performed by general element survey and specified software. Precision (RSD) below 5% is commonly achieved for elements present at 25pgl . To correct for matrix-induced ion signal variation and instrumental drift, rhodium or indium in combination with panoramic analysis, based on full mass-spectra scan methods, is used as the internal standard (IS). Spectroscopic effects due to Cl, Na, Ca, Mg, S, and C were corrected with interference factors (IF) on the basis of a set of correction equations (see Table 5). [Pg.4991]


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See also in sourсe #XX -- [ Pg.79 , Pg.80 , Pg.81 ]




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Combined signal

Spectroscopic analysis

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