@article{oai:nipr.repo.nii.ac.jp:00004554,
 author = {Kagi, Hiroyuki and Takahashi, Kazuya and Shimizu, Hiroshi and Kitajima, Fumio and Masuda, Akimasa},
 journal = {Proceedings of the NIPR Symposium on Antarctic Meteorites},
 month = {Mar},
 note = {P(論文), The fine structures of graphitic materials contained in four Antarctic ureilites (ALH-77257,ALH-78019,MET-78008 and Y-791538) were investigated using a laser light (514.5nm), which could be focused onto a spot of 1μm in diameter. Raman spectra obtained differ not only among individual ureilite samples, but also among positions within a single carbonaceous vein of the same specimen. Moreover, one can classify the carbon into several groups on the basis of the spectra concerned. For all samples, both well-ordered graphitic carbon and semi-ordered graphitic carbon were observed. Amorphous carbon was detected in ALH-77257 and MET-78008. The difference in structural ordering among the samples is attributed to the difference in distribution of the components of carbonaceous material, indicating minor difference in genetic conditions or in locality within the parent body. Structural heterogeneity of carbon within a single carbonaceous vein implies the occurrence of two (or three) types of carbonaceous matters which have fairly different physicochemical properties and distinct histories. For the genesis of the carbonaceous matter in ureilites, a two-stage model is proposed assuming the graphite crystallization from metallic phase followed by the inflow of semi-ordered graphitic carbon or amorphous carbon into the well-ordered graphitic carbon produced from the metal.},
 pages = {371--383},
 title = {In-situ micro Raman studies on graphitic carbon in some Antarctic ureilites},
 volume = {4},
 year = {1991}
}