Spectra enamel

The room was made dark and when a hot glass tube had cooled until it was just barely visible, a fragment of iodine was thrown into the tube, which thereupon filled with luminous vapours. To obtain more brilliancy one heats the vapour of iodine in a Bohemian glass tube by means of an enameller s lamp. The contents of the tube look like a red-hot bar of iron. One may also volatilize iodine around a platinum spiral brought to a vivid incandescence the luminous vapour rises like a real flame about the spiral. It is a case of farm without combustion. The light from the iodine gives a continuous spectrum, or rather a confused primary spectrum one perceives traces of characteristic channellings but no lines of the secondary spectrum. 

Raman spectroscopy is well suited for examining calcified tissues such as bones and teeth owing to its ability to probe both the inorganic and organic constituents of the tissue. The frequency and band shape of the symmetric and asymmetric phosphate stretching vibrations provide critical information on the crystallinity and orientation of the hydroxyapatite matrix. The analysis of a Raman spectrum of dental enamel provides features that are highly characteristic of the health and integrity of the tissue. 

Prior to the work of Kazanski et al. there was almost no mention of polarization effects in the bone Raman literature, although the polarized Raman spectrum of dental enamel was reported as early as 1994 [36]. The reason may well be that most Raman spectra of cortical bone have been obtained by... 

A more detailed examination of the composition of the variously colored enameled areas was then carried out by masking all but the regions under study with double layers of 0.007-in. (0.18-mm) tin sheet of high purity. The tin by itself showed no peaks other than that of tin in the XRF spectrum, even when placed on a copper substrate. Hence the tin masks cannot have contributed to the observed peaks, nor can any of the signals detected have come from areas under the tin masks. Similar masking was performed for regions on the reliquary. 

Figure 5. XRF spectrum from the cross. The green enamel near the upper arm showed major copper and lead peaks.

Figure 11. XRF spectrum of the red enameled spot on the reliquary showing only the major copper peaks.

Figure 12, XRF spectrum of a light blue enameled region on the reliquary showing the major copper peaks and the Ka peak of iron.

The enamel on the reliquary, which is thinner than that on the cross, gave strong copper signals in all cases. The red spot showed only copper, and the light blue enamel contained iron the spectrum of the green enamel showed small peaks for nickel and gold. No lead was detected in any of the enameled areas on the reliquary. 

Beshah et al. [23] also showed an enamel CP spectrum, in which a large CHA-B peak and a small CHA-A peak can be easily discerned. The CO3" ions... 

Another 25% of the selenium production in 1996 was used in inorganic pigments (principally as cadmium sulfoselenide used in plastics, paints, enamels, inks, mbber, and ceramics), and 10-15% of selenium is used in a broad spectrum of applications including accelerators and vulcanizing agents in mbber production, in stainless steel, and as selenides of refractory metals for use in lubricants. Some of these products may end up as disposed waste. Medical and pharmaceutical uses such as in topical preparations for treatment of dandmff, for... 

At the other end of the spectrum, pressure-sensitive adhesives, contact adhesives, aqueous varnishes, clear sealants and caulks, overprint varnishes for metal decorating and printing are essentially pigment free. Minor amounts of silica are used for gloss reduction in the case of varnishes. Carpet, construction and ceramic/brick adhesives may contain substantial amounts of filler, not only to reduce cost but also to provide shear strength. Gloss and semi-gloss latex enamels... 

Fig. 19.14. Polarized infrared absorption spectrum ofthe carbonate ion that has replaced hydroxyl ions in the apatite lattice. (A) A 100- i longitudinal section of enamel heated at 1100°C in air for 2 hr. (B) A 50-/t longitudinal section of enamel heated at 900 C in CO2 for 30 min. (Elliott, 1965.)...

Approximate axial g-tensors are frequently observed for transition metal ion complexes. Inorganic radicals can also have appreciable axial g-anisotropy. This property is of value for the assignment of ESR powder spectra in applied studies. Carbon dioxide radical anions, CO2, and related species contribute for instance to the ESR signal used for geological dating [21] see Chapter 9. The ESR spectrum of this anion has also been employed as an indicator that a certain foodstuff has been irradiated, for dosimetric purposes in certain carboxylic acid salts, and as a component in tooth enamel samples used in retrospective dosimetry. 

Fig. 4. IR and Raman spectra of yellow acrylic melamine enamel auto paint with pigments (A) IR spectrum of the auto paint (B) IR spectrum of chrome yellow pigment (C) Raman spectrum of chrome yellow pigment (D) Raman spectrum of the yellow auto paint (E) Raman spectrum of rutile. Spectra provided by E. Suzuki, Washington State Patrol, Forensic Laboratory, Seattle, Wash.

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