Spectroscopy of high-temperature

Electronic spectroscopy of high temperature open-shell polyatomic molecules. D. M. Gruen, Prog. Inorg. Chem., 1971,14,119 -172 (148). 

Gruen, D. M., Electronic Spectroscopy of High Temperature Open-Shell... 

E. Ya. Sherman, O. V. Misochko, and P. Lemmens, in Spectroscopy of High Temperature Superconductors, Ed. N.M. Plakida (Taylor Francis Inc., London and New York, 2003), Chap. What can one learn from Raman Spectra of High Temperature Superconductors , pp. 97-157, and references within. 

Vibrational Spectroscopy of High Temperature Metal-Halide Vapor Complexes... 

Multichannel Extreme UV Spectroscopy of High Temperature Plasmas... 

Chronister E L and Crowell R A 1991 Time-resolved coherent Raman spectroscopy of low-temperature molecular solids in a high-pressure diamond anvil cell Chem. Phys. Lett. 182 27... 

Figure 7. Total internal reflection sum frequency generation (TIR-SFG) vibrational spectroscopy of high-pressure room temperature adsorption of carbon monoxide on PVP-protected Pt cube monolayers and calcined (373 K, 3h) monolayers [27], The infrared spectra demonstrate CO is adsorbed at atop sites, but is considerably red-shifted on the PVP-protected Pt cubes. After calcination, the atop frequency blueshifts to 2085 cm in good agreement with CO adsorption on Pt(l 0 0) at high coverages [28], (Reprinted from Ref [27], 2006, with permission from American Chemical Society.)...

Dynamics of High-Temperature Carbon Monoxide Chemisorption on Platinum-Alumina by Fast-Response IR Spectroscopy... 

Research in the areas of high temperature chemistry, fluorine chemistry, optical and mass spectroscopy and thermodynamics has been supported at Rice University by the United States Atomic Energy Commission, by the US. Army Research Office (Durham), by the National Aeronautics and Space Administration, by the Petroleum Research Fund of the American Chemical Society and by the Robert A. Welch Foundation. Liquid helium for low temperature nock was provided through arrangements with the U.S. offices of Naval Research. 

NMR) [24], and Fourier transform-infrared (FT-IR) spectroscopy [25] are commonly applied methods. Analysis using mass spectrometric (MS) techniques has been achieved with gas chromatography-mass spectrometry (GC-MS), with chemical ionisation (Cl) often more informative than conventional electron impact (El) ionisation [26]. For the qualitative and quantitative characterisation of silicone polyether copolymers in particular, SEC, NMR, and FT-IR have also been demonstrated as useful and informative methods [22] and the application of high-temperature GC and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) is also described [5]. 

Atomic absorption spectroscopy is highly specific and there are very few cases of interference due to the similar emission lines from different elements. General interference effects, such as anionic and matrix effects, are very similar to those described under flame emission photometry and generally result in reduced absorbance values being recorded. Similarly, the use of high temperature flames may result in reduced absorbance values due to ionization effects. However, ionization of a test element can often be minimized by incorporating an excess of an ionizable metal, e.g. potassium or caesium, in both the standards and samples. This will suppress the ionization of the test element and in effect increase the number of test atoms in the flame. 

In this study, we analyze this situation using Si-MAS-NMR spectroscopy and high-temperature ammonia-adsorption calorimetry. The acid strength will be determined from the heat of adsorption of ammonia. On adsorption of ammonia, the reaction. 

Analysis by atomic (or optical) emission spectroscopy is based on the study of radiation emitted by atoms in their excited state, ionised by the effect of high temperature. All elements can be measured by this technique, in contrast to conventional flames that only allow the analysis of a limited number of elements. Emission spectra, which are obtained in an electron rich environment, are more complex than in flame emission. Therefore, the optical part of the spectrometer has to be of very high quality to resolve interferences and matrix effects.-... 

The interpretation of the intensities of lines observed in astrophysical sources requires a wide variety of reliable atomic and, to a lesser extent, molecular data [1]. Also, the steady development of high temperature plasmas, in relation to the fusion programmes ongoing in several countries, has given rise to a considerable interest in the spectroscopy ofheavy and/or highly ionised atoms [2], The spectacular advance of some experimental techniques has not diminished the need for reliable theoretical data. In the production of spectroscopic quantities such as oscillator strengths to fulfill the present demands of both the astrophysics and plasma physics communities, several authors [3-5] have emphasised the need for both experimentalists and theoreticians to self-assess the data they supply. 

Iliev, et al. (2006), Raman Spectroscopy of Low-temperature (Pnma) and High-temperature (R3 c) Phases of LaCr03 , Physical Review, B 74, 214301. 

Because of the rapidly increasing availability of cryocoolers, numerous new applications have become possible many of these involve infrared imaging systems, spectroscopy, and high-temperature superconductors in the medical and communication fields. Many of these applications have required additional control of cryocooler-generated vibration and EMI susceptibility. 

Kortiim (90), and Klier (91) and reviews on the subject have been published by Terenin (92) and by Leftin and Hobson (93). The potentialities of high-temperature reflectance spectroscopy (HTRS) and of dynamic reflectance spectroscopy (DRS), as described by Wendlandt (94), should be emphasized in connection with surface chemical problems. In the HTRS technique, reflectance spectra are recorded at constant elevated sample temperature, whereas in the DRS technique, the temperature is uniformly changed (usually increased) and the reflectance recorded at a fixed wave number. The results of DRS experiments if carried out under vacuum or with an inert carrier gas may, therefore, valuably, complement thermogravimetric or TPD experiments. 

Figure 6.49. In situ AC impedance spectroscopy at a frequency range of 3500 to 0.1 Hz at 0.91 A/cm2, 100% RH, and 30 psig pressure at 80°C, 100°C, and 120°C [44]. (Reproduced by permission of ECS—The Electrochemical Society, and of the authors, from Tang Y, Zhang J, Song C, Liu H, Zhang J, Wang H, MacKinnon S, Peckham T, Li J, McDermid S, Kozak P, Temperature dependent performance and in situ AC impedance of high temperature PEM fuel cells using the Nafionl 12 membrane.)...

For chemical applications, vibrational spectroscopy of high-pressure fluid phases, including liquids and compressed gases, is of special importance (Buback, 1991). The fluid, i.e., the non-solid region of a substance, is illustrated in Fig. 6.7-2. The packing density of the circles is approximately proportional to the density of a substance. The bottom left part of Fig. 6.7-2 shows the vapor pressure curve which, up to the critical point, separates the liquid phase from the gas phase. Above the critical temperature (7 ), the density of a substance may change continuously between gaseous and liquid like states vibrational spectroscopic methods make it possible to study the structure and dynamics... 

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