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61.
Cai Mengmeng Yao Lijuan Zhu Man Tao Peng Nan Ruihua Jian Zengyun 《Journal of Thermal Analysis and Calorimetry》2021,143(4):2911-2918
Journal of Thermal Analysis and Calorimetry - Differential scanning calorimetry was used to investigate the non-isothermal crystallization kinetics of the Fe76.5Nb3B20Cu0.5 glassy alloys. The... 相似文献
62.
Hong-Jian Ji Jia-Yuan Li Shi-Fei Wu Wen-Yong Wu Chang-Liang Yao Shuai Yao Jian-Qing Zhang De-An Guo 《Molecules (Basel, Switzerland)》2021,26(1)
Twelve compounds, including two new aristolochic acid analogues with a formyloxy moiety (9–10) and 10 known aristolochic acid derivates (1–8 and 11–12), were obtained from the roots of Aristolochia contorta. Their structures were elucidated using extensive spectroscopic methods. Their cytotoxic activity in human proximal tubular cells HK-2 was evaluated by the MTT method, which has been widely used to assess cell viability. Among these molecules, compounds 3 and 9 were found to be more cytotoxic. Furthermore, molecular modeling was used to evaluate, for the first time, the interactions of compounds 3 and 9 with the target protein organic anionic transporter 1 (OAT1) that plays a key role in mediating aristolochic acid nephropathy. Structure–activity relationships are briefly discussed. 相似文献
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The electronic structure and the magnetic properties of transition metal phosphonate Co(PhPO3)·H2O have been studied by first-principles within the density-functional theory (DFT) and the full potential linearized augmented plane wave (FP-LAPW) method. The total energy, the total magnetic moment, the atomic spin magnetic moments and the density of states(DOS) of Co(PhPO3)·H2O were all calculated. The calculations reveal that the title compound is a metallic antiferromagnet and has a metallic ferromagnetic metastable state, which are in good agreement with the experiment. The spin magnetic moment of Co(PhPO3)·H2O is about 4.93 μB per molecule, and it is mainly assembled at the cobalt atom, at the same time, with a little contribution from the P, O1, O2, O3. 相似文献
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A robust and fast line detection method based on Hough transform (HT) is proposed in this paper. Edge pixels are extracted based on the summation and ratio of principal curvatures. Probabilistic sampling on the edge pixels is applied to reduce the count of voting. Then a one-to-one voting strategy is applied by taking advantages of the information of principal direction. The principal direction is also conducive for the successive accurate line segment extraction. The experiments demonstrate that the proposed method shows better locating accuracy and computation efficiency compared with several significant variations of HT. 相似文献
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An Unusual Triphenylphosphine Oxide Catalyzed Stereoselective 1,3‐Dichlorination of Unsaturated Ketoesters 下载免费PDF全文
Tian‐Yang Yu Yao Wang Peng‐Fei Xu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(1):98-101
An unusual Ph3PO‐catalyzed stereoselective 1,3‐dicholorination of an unsaturated ketoester has been developed. The novel activation mode involved in this cascade reaction can promote consecutively elusive transformations. The products were obtained with good yields and excellent stereoselectivities. This reaction makes important complementation to the limitations associated with the field of dichlorination. 相似文献