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1.
Biodivers Data J ; 12: e127089, 2024.
Article in English | MEDLINE | ID: mdl-38974675

ABSTRACT

Background: Two species of Neoperla from Guizhou Province, China, N.bituberculata Du, 2000 and N.dashahena Du, 2005 were described with brief morphological descriptions available only in Chinese and original illustrations being somewhat blurry. Recently, we examined type material of these two species and re-described them with clear colour pictures for the first time. New information: In this paper, detailed English descriptions and colour pictures of Neoperlabituberculata and N.dashahena are provided for the first time. The type locality of N.mnong Stark is from Vietnam and its geographical distribution is also discussed. Additionally, we also recorded the distribution of N.mnong Stark, 1987 in Guizhou, Hunan and Jiangxi Provinces of China for the first time and provided a geographical distribution map of this species.

2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(6): 1534-8, 2015 Jun.
Article in Chinese | MEDLINE | ID: mdl-26601362

ABSTRACT

The results of Micro-FTIR spectra analysis of the euhedral faceted polycrystalline diamonds (EFPCDs) from the Western Yangtze Craton show that the EFPCDs are mostly IaAB type, the concentration of nitrogen.varies greatly from 25. 70- 358.35 µg x g(-1). Different nitrogen content distributes in different diamond grains or position in same sample. The C Center was not found in the samples and the conversion from A center to B center is incomplete, in the meanwhile, B% value concentrated in 40%. Thus, polycrystalline diamonds are not formed in the stage of nucleation but gathered together after formation of the individual diamond grains during the residence time in the mantle. And its formation environment is. more complex than the euhedral faceted polycrystalline diamonds from Mengyin kimberlite, the Eastern of North China Craton. The diamonds extremely possibly originated in the deep mantle from 160 to 180 km, reaching the depth of the core of the Yangtze Craton, at the same time it is close to the bottom of the lithosphere. The C-H bond of sp2 hybridization are conducive to the formation of platelets in diamonds. Meanwhile, its concentrations are generally higher than the C-H bond of sp3 hybridization in the samples.

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