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Spectroscopy, electronic

CELS, EIS Characteristic-energy-loss spectroscopy, electron-impact spectroscopy [128] Same as EELS Same as EELS... [Pg.314]

Acrylonitrile has been characterized using infrared, Raman, and ultraviolet spectroscopies, electron diffraction, and mass spectroscopy (10—18). [Pg.181]

X-Ray Photoelearon Spectroscopy X-Ray Photoemission Spectroscopy Electron Spectroscopy for Chemical Analysis X-Ray Photoelectron Diffraction Photoelectron Diffraction Kinetic Energy... [Pg.769]

Further aspects of the reaction of aromatic tertiary hydroxyl amines have been examined by more sophisticated techniques [49]. 2-Methyl-2-nitrosopropane was used as a radical trap, and the endgroups on PMMA resulting from its addition were detectable by ultraviolet spectroscopy. Electron spin resonance results on the same system have also been reported [50]. [Pg.835]

Phospholipids, which are one of the main structural components of the membrane, are present primarily as bilayers, as shown by molecular spectroscopy, electron microscopy and membrane transport studies (see Section 6.4.4). Phospholipid mobility in the membrane is limited. Rotational and vibrational motion is very rapid (the amplitude of the vibration of the alkyl chains increases with increasing distance from the polar head). Lateral diffusion is also fast (in the direction parallel to the membrane surface). In contrast, transport of the phospholipid from one side of the membrane to the other (flip-flop) is very slow. These properties are typical for the liquid-crystal type of membranes, characterized chiefly by ordering along a single coordinate. When decreasing the temperature (passing the transition or Kraft point, characteristic for various phospholipids), the liquid-crystalline bilayer is converted into the crystalline (gel) structure, where movement in the plane is impossible. [Pg.449]

The complexes /uo[IrL3X(OH2)], HL = phthalimide, X = bpy, phen, have been prepared and characterized by IR and UV-vis spectroscopy, electronic conductance and magnetic measurements.117... [Pg.163]

MSssbauer spectroscopy Electron spin resonance spectroscopy Colorimetry Thermoluminescence Thermal analysis differential thermal analysis, dilatometry... [Pg.282]

On the basis of a number of physico-chemical methods (Mossbauer spectroscopy, electron diffraction, EXAFS) the iron cores of naturally occurring haemosiderins isolated from various iron-loaded animals and man (horse, reindeer, birds and human old age) were consistently shown to have ferrihydrite-like iron cores similar to those of ferritin (Ward et ah, 1992, 2000). In marked contrast, in the tissues of patients with two pathogenic iron-loading syndromes, genetic haemochromatosis and thalassaemia, the haemosiderins isolated had predominantly amorphous ferric oxide and goethite cores, respectively (Dickson etah, 1988 Mann etah, 1988 ... [Pg.196]

Ffirai and Toshima have published several reports on the synthesis of transition-metal nanoparticles by alcoholic reduction of metal salts in the presence of a polymer such as polyvinylalcohol (PVA) or polyvinylpyrrolidone (PVP). This simple and reproducible process can be applied for the preparation of monometallic [32, 33] or bimetallic [34—39] nanoparticles. In this series of articles, the nanoparticles are characterized by different techniques such as transmission electronic microscopy (TEM), UV-visible spectroscopy, electron diffraction (EDX), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) or extended X-ray absorption fine structure (EXAFS, bimetallic systems). The great majority of the particles have a uniform size between 1 and 3 nm. These nanomaterials are efficient catalysts for olefin or diene hydrogenation under mild conditions (30°C, Ph2 = 1 bar)- In the case of bimetallic catalysts, the catalytic activity was seen to depend on their metal composition, and this may also have an influence on the selectivity of the partial hydrogenation of dienes. [Pg.220]

Vibrations in molecules or in solid lattices are excited by the absorption of photons (infrared spectroscopy), or by the scattering of photons (Raman spectroscopy), electrons (electron energy loss spectroscopy) or neutrons (inelastic neutron scattering). If the vibration is excited by the interaction of the bond with a wave... [Pg.216]

Let us take 1978 as the starting point. Massoth [51] then published an extensive review of what was known about the structure of HDS catalysts. Characterization was essentially based on techniques such as X-ray diffraction, electron microscopy, photoelectron spectroscopy, electron spin resonance and magnetic methods. Massoth was rather unhappy with the state of affairs in 1978. He was struck by the ...diversity and apparent contradictions of results and interpretations... It almost seems as though everyone is working with a different catalyst . [Pg.267]

Voltammetry Assisted by Auger Spectroscopy, Electron Energy-Loss Spectroscopy, and Low-Energy Electron Diffraction... [Pg.8]

P.E. Spectroscopy, Electronic Absorption Spectroscopy and Ligand Field Theory.124... [Pg.119]

In Situ Spectroscopy—Electronic Structure and Redox Behavior of Nickel... [Pg.189]

Studies of the inorganics in cotton dust have incorporated the use of a wide variety of techniques. These include X-ray fluorescence spectroscopy, atomic absorption spectroscopy, electron microscopy, energy dispersive analysis of X-rays, X-ray diffraction, atomic absorption spectroscopy, neutron activation analysis and petrographic microscopy. It is necessary to use a wide array of techniques since no single technique will permit the measurement of all trace elements. Steindard chemical techniques to determine the ash content of samples and of various extracts have also been used. In most of these studies the ash fraction has been considered to be a reasonably accurate measure of the inorganic content. [Pg.314]


See other pages where Spectroscopy, electronic is mentioned: [Pg.559]    [Pg.1307]    [Pg.1622]    [Pg.105]    [Pg.50]    [Pg.2]    [Pg.371]    [Pg.667]    [Pg.17]    [Pg.30]    [Pg.358]    [Pg.176]    [Pg.236]    [Pg.6]    [Pg.158]    [Pg.244]    [Pg.144]    [Pg.129]    [Pg.558]    [Pg.784]    [Pg.63]    [Pg.361]    [Pg.226]    [Pg.569]    [Pg.305]    [Pg.487]    [Pg.49]    [Pg.223]    [Pg.227]    [Pg.124]    [Pg.106]    [Pg.376]   
See also in sourсe #XX -- [ Pg.690 ]

See also in sourсe #XX -- [ Pg.742 , Pg.748 ]

See also in sourсe #XX -- [ Pg.316 ]

See also in sourсe #XX -- [ Pg.136 ]




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