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The identification, analysis, and occurrence in U.S. automobile original finishes (1974-1989) of Nickel Titanate (yellow) and Chrome Titanate (yellow-orange) are described in this report. The titanate pigments are based on the rutile (titanium dioxide) structure and there are only minor differences between the infrared absorptions of rutile and the titanates. Titanate pigment absorptions in paint spectra can thus be easily mistaken for those of rutile. Each of the titanates, however, contains two elements in addition to titanium that can serve to distinguish them using elemental analyses. Fourier transform infrared (4000-220 cm(-1)) and X-ray fluorescence instruments were used in combination for the in situ analysis of the titanates. In addition to titanium, nickel, and antimony, the three main detectable elements comprising Nickel Titanate, all of the commercial products of this pigment that were examined also contained impurities of zirconium, niobium, and usually lead. These elements were also detected in most of the monocoats in which Nickel Titanate was identified, as well as in the Chrome Titanate pigments, and the zirconium to niobium ratio was found to exhibit a wide variation. Nickel Titanate is a relatively common pigment that was identified in nearly three dozen U.S. automobile yellow nonmetallic monocoats (1974-1989), while Chrome Titanate appears to have been used in only a few yellow and orange nonmetallic monocoats. The use of the titanate pigments likely increased after this time period as they were replacements for lead chromate pigments (last used in a U.S. automobile original finish in the early 1990s), and are more amenable for use in basecoat/clearcoat finishes than in monocoats. Minor distortions of the infrared absorptions of rutile, anatase, and the titanates obtained using accessories with diamond windows were noted, and their origins are discussed. 相似文献
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Identification of skulls by video superimposition 总被引:2,自引:0,他引:2
P X Iten 《Journal of forensic sciences》1987,32(1):173-188
A method of matching skulls with photographic portraits or impressions of the face in clay by video superimposition is described. Two different practical cases are presented. The first one deals with the identification of a skull of a six-year-old girl, the second with the identification of the skull of the famous Swiss Pedagogue Johann Heinrich Pestalozzi, who died about 160 years ago. The advantages and versatility of this method are shown; also the setup of the equipment and the working technique. 相似文献
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Authors report an unusual suicide undertaken by a medical person who after applying the local anesthetic lidocaine, opened a leg vein with a scalpel. The cause of the suicide was presumed advanced AIDS symptoms with a progressive Kaposi sarcoma and Non-Hodgkin lymphoma. For the toxicological investigation of the tissue we used the stomacher extraction system, a method not widely known in Forensic science, however, recommended for the extraction of all infectious tissues. 相似文献
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Renato G. Flôres Jr. Marcos De B. Monteiro Ariane Szafarz 《Economic Change and Restructuring》1994,27(3):277-292
This paper analyses exchange rate series for Poland and Brazil. The Polish series, related to the period soon after the first liberalizing measures, presents a high volatility which is not accounted for by some selected ‘fundamentals’. The Brazilian series, though also keeping evidence of excessive volatility, is cointegrated with fundamentals similar to those of the Polish case. This raises the issue of a learning process taking place during persistent inflations. Unsuccessful one-shot stabilization plans can reinforce this process, leaving a lasting imprint in the excessive volatility pattern. The message seems clear, though maybe not easy to implement: agents take some time to learn to live in non-stable environments; to avoid this by one-shot measures — if unsuccessful — can have a very high cost and pre-empt future corrections. 相似文献