Paint, comparison with other

Use of inductively coupled plasma-mass spectrometry (1CP-MS) coupled to a laser-ablation sample introduction system (LA-ICP-MS) as a minimally destructive method for chemical characterization of archaeological materials has gained favor during the past few years. Although still a relatively new analytical technique in archaeology, LA-ICP-MS has been demonstrated to be a productive avenue of research for chemical characterization of obsidian, chert, pottery, painted and glazed surfaces, and human bone and teeth. Archaeological applications of LA-ICP-MS and comparisons with other analytical methods are described. 

Traces are identified by determining their chemical composition and certain physicochemical properties, and comparison with reference material (database) or comparative material collected from the suspect. Criminalistic laboratories create extensive databases on the physical features and production of glass, paints, papers, fabrics and other materials, as well as collecting thousands of samples for comparison purposes. 

In a rotating paddle viscometer, such as the Krebs-Stormer viscometer commonly used in the paint industry, the shear rate and shear stress caimot be calculated, although it is possible to estimate them by comparison with results from other instmments. 

Paint evidence is usually submitted to the forensic scientist for comparison with paint from a known soimce. Automotive, architectural, art, marine, aircraft, tool, and other types of paints may become evidence in a variety of crime scenarios (43). Within the United States, most of these examinations involve automotive finishes as related to antomotive accidents and hit-and-run cases. The question frequently posed is, what kind of vehicle could have contributed the paint flakes recovered from the scene of a hit-and-run homicide case Additionally, house paints may be examined in connection with biu-glaries, and paint from tools in cases involving industrial sabotage. Rarely is it necessary to determine the manufacturer of a particular paint. 

Third International Radiocarbon Intercomparison (TIRI) standard wood samples (5,6,8) and four different archaeological charcoal samples (2,3J8) for comparison with dates previously determined at other laboratories using standard combustion methods. These measurements were utilized to demonstrate the viability of the plasma extraction technique for dating rock paintings from around the world with charcoal and inorganic pigments. 

Beyond paints, fibers, and other polymers, PGC has been applied in the forensic science laboratory to characterize and compare a number of different types of material submitted as evidence in criminal casework. The utility of PGC for the characterization of adhesives has been described (253,272), as well as various methods for the comparison of tapes with adhesive backings (273). Vinyl tile with an asphalt-type glue from a safe-cracking case was analyzed by PGC (274). Williams and Munson (275) used capillary column PGC to examine 30 black... 

The addition of an alcohol before, during or after the neutralization results in an aqueous coating composition [181] that can form films that are not only superior in the resistance to corrosion and to water, but also have favorable physical properties such as hardness, adhesion, impact strength, and flexibility. They show excellent draining properties in electrodeposition paint and exhibit a remarkably improved performance in comparison with paints based on other LMWPBs such as cis-1,4-polybutadiene as the starting material [182]. 

One of the best known color classification systems is that of Munsell which was devised in the early part of this century. The System relies on three attributes of color hue, chroma, and value. Hue refers to the color quality that is described by words like red, blue, and green in other words, the name of the color. Chroma is used to describe the purity or saturation of a color. It may be thought of as how dirty or clean a color is perceived to be. Value is the color term which we use to describe how light or dark a color is. The Munsell system plots color on a three-dimensional coordinate system in which the vertical axis represents value and the radial axis represents chroma. The various hues are arranged around the periphery of the three-dimensional solid. The Munsell Book of Color is a compilation of some 1500 painted paper chips which allow for comparison with a sample color. Approximately 100,000 colors can be distinguished in the Munsell system by interpolation [15]. A color representation of the Munsell system can be found in the books by Billmeyer and Saltzman [6], Overheim and Wagner [11], and Hunt [14] or on the Munsell homepage [16]. 

It was different. Here the former ambassador displayed his souvenirs— rich silk mgs on the floor and walls, ornate silver urns, carved ivory tables, and other oddities. The ceiling painting seemed old and faded by comparison and, with the big doors out to the balcony closed, the air held a peculiar, foreign scent that I disliked. I did my dowsing as fast as I could without breaking out of my role and returned to the doorway, where Vasco watched me with amused contempt and Grazia with extreme displeasure. 

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