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151.
The study of terranes has already become an important subject in research of the Circum-Pacific continental margin. This paper discusses proper understanding of the terrane conception and identifies existence of the Nadanhada terrane according to its difference from the neighbouring massifs in terms of evolutionary history, tectonic background, and deformation features, and to the fault-contact relation between them; analyzes the paleogeographic position variation of the Nadanhada terrane during the Triassic to late Jurassic and the period when the terrane was attached to the ancient continental marging; finally discusses the consequential effects of theterrane accretion from the observed tectonic events after terrane collage. 相似文献
152.
时间分辨背景校正原子吸收光谱仪 总被引:1,自引:0,他引:1
根据本工作发现镍离子线(231.6nm)形态可以被任意改变的规律,研制了双通路时间分辨背景校正原子吸收光谱仪。它比氘灯、S-H法和塞曼效应背景校正线路具有更高的灵敏度。 相似文献
153.
154.
Two new cucurbitane-type triterpenoids,(23E)-5β,19-epoxycucurbita-6,23,25-triene-3β-ol(1) and(19R,23E)-5/β,19-epoxy- 19-ethoxycucurbita-6,23-diene~3β,25-diol(2),together with three known compounds,have been isolated from the fruit of Momordica charantia L.Their structures were determined on the basis of spectral analysis.Their cytotoxic activity was tested on 5 cancer cell lines,MCF-7,HepG2,Dul45,Colon205 and HL-60 by MTT assay.Compounds 1,3 and 4 showed weak cytotoxicity. 相似文献
155.
Shenyang Xu Xinghua Tan Wangyang Ding Wenju Ren Qi Zhao Weiyuan Huang Jiajie Liu Rui Qi Yongxin Zhang Jiachao Yang Changjian Zuo Haocheng Ji Hengyu Ren Bo Cao Haoyu Xue Zhihai Gao Haocong Yi Wenguang Zhao Yinguo Xiao Qinghe Zhao Mingjian Zhang Feng Pan 《Angewandte Chemie (International ed. in English)》2023,62(10):e202218595
The cathode materials work as the host framework for both Li+ diffusion and electron transport in Li-ion batteries. The Li+ diffusion property is always the research focus, while the electron transport property is less studied. Herein, we propose a unique strategy to elevate the rate performance through promoting the surface electric conductivity. Specifically, a disordered rock-salt phase was coherently constructed at the surface of LiCoO2, promoting the surface electric conductivity by over one magnitude. It increased the effective voltage (Veff) imposed in the bulk, thus driving more Li+ extraction/insertion and making LiCoO2 exhibit superior rate capability (154 mAh g−1 at 10 C), and excellent cycling performance (93 % after 1000 cycles at 10 C). The universality of this strategy was confirmed by another surface design and a simulation. Our findings provide a new angle for developing high-rate cathode materials by tuning the surface electron transport property. 相似文献
156.
A new coumadn was obtained from the stems and roots of Wikstroemia indica (L.) C.A.Mey.Its structure was elucidated as methyl 3-(2-hydroxy-4-(7-hydroxy-6-methoxy-2-oxo-2H-chromen-3-yloxy) phenyl) propanoate by spectroscopic methods. 相似文献