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1.

0379101 - ÚOCHB 2013 RIV DE eng J - Journal Article
Vávra, Jan - Severa, Lukáš - Švec, Pavel - Císařová, I. - Koval, Dušan - Sázelová, Petra - Kašička, Václav - Teplý, Filip
Preferential Crystallization of a Helicene-Viologen Hybrid - An Efficient Method to Resolve [5]Helquat Enantiomers on a 20 g Scale.
European Journal of Organic Chemistry. -, č. 3 (2012), s. 489-499. ISSN 1434-193X. E-ISSN 1099-0690
R&D Projects: GA ČR GAP207/10/2391; GA ČR(CZ) GA203/08/1428; GA ČR GP203/09/P485
Institutional research plan: CEZ:AV0Z40550506
Keywords : helical structures * helicene-viologen hybrid * crystal growth * synthetic methods * conglomerates
Subject RIV: CC - Organic Chemistry
Impact factor: 3.344, year: 2012 ; AIS: 0.776, rok: 2012
DOI: https://doi.org/10.1002/ejoc.201101367

The bistriflate salt of racemic [5]helquat 1 was found to form a conglomerate. Based on this finding, the preferential crystallization of this chiral helicene–viologen hybrid was developed to deliver pure enantiomers on a 20 g scale (10.5 g of each enantiomer). To the best of our knowledge, this is the largest amount of nonracemic helicene-like compound obtained by preferential crystallization to date. The absolute configuration of the P enantiomer was confirmed by X-ray crystal structure analysis. The chromatography-free synthesis of racemic 1 on a multigram scale (30 g) is also presented as an entry point to this resolution study.
Permanent Link: http://hdl.handle.net/11104/0210371

2.

0132947 - FZU-D 20000205 RIV JP eng C - Conference Paper (international conference)
Jirsa, Miloš - Muralidhar, M. - Murakami, M. - Noto, K.
Pinning and scaling behavior in RE-123 materials.
Proceedings of the 62nd Meeting on Cryogenics and Superconductivity. Tsukuba: ETL, 2000, s. 210-211. ISSN 0919-5998.
[Meeting on Cryogenics and Superconductivity /62./. Tsukuba (JP), 29.05.2000-31.05.2000]
R&D Projects: GA AV ČR IAA1010919
Institutional research plan: CEZ:AV0Z1010914
Subject RIV: BM - Solid Matter Physics ; Magnetism

While the clean and weakly pinned samples help in a study of the elementary processes of flux dynamics in HTS,for applications is important the limit of strong pinning. In this paper is indicated that the increasing pinning disorder results in an increase of the peak height but at the same time in a decrease of the secondary peak position.
Permanent Link: http://hdl.handle.net/11104/0030939

3.

0365550 - MÚA 2012 CZ cze N - Newspaper Article
Bahenská, Marie
Ferdinand Stiebitz (1894-1961).
Akademický bulletin AV ČR. -, č. 10 (2011), s. 31. ISSN 1210-9525
Institutional research plan: CEZ:AV0Z80770509
Keywords : Stiebitz, Ferdinand * history of filology
Subject RIV: AB - History
Permanent Link: http://hdl.handle.net/11104/0200770