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Application of refractive index (RI) measurement and analysis of trace impurities with synchrotron radiation X-ray ‰uorescence spectrometry (SR-XRF) was investigated for the forensic discrimination of headlight glasses. Glass fragments smaller than 1 mm were collected from 17 kinds of diŠerent headlight samples for this experiment. It was found that glass fragments taken from the surface of the headlight was not appropriate for the forensic comparison and should be excluded from the RI measurement, because some of them showed inappropriate RI values diŠerent from those of the fragments from the bulk. Discrimination of headlights was carried out by comparing the range of average RI value ±2SD among 136 possi

A variety of evidence samples have been brought into the Identiˆcation section of the police for detection of latentˆngerprints. Fumes of cyanoacrylate ester are generally used to detect latentˆngerprints on ‰at surfaces, such as cutlery, in a case of murder. Whiteˆngerprint ridgesˆxed by the fumes are generally stained with dye powder or dye solution.We developed new reagents which can detect latentˆngerprints the same method as using both the fumes of cyanoacrylate ester and ‰uorescent staining. First, polycyanoacrylate ester powder was produced from its monomer and water as an initiator. Then, 5 percent of p-dimethylaminocinnamaldehyde (DMAC) or pdimethylaminobenzaldehyde (DMAB), each of which has volatility and ‰uores-cence that could be excited by ultraviolet light or blue light respectively, was added to the polycyanoacrylate ester powder. The developed reagent depolymerized and yielded monomer at a lower temperature than polycyanoacrylate powder that polymerized in methanol containing 1 water. The mixed DMAC or DMAB can simultaneously stain and give ‰uorescence to the whiteˆngerprint ridge. Added to that, exposing samples to acetic acid vapor for a short time has increased the ‰uorescence intensity and shifted excitation wavelength to a longer one such as ultraviolet to blue