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HowardD. Flack 《Helvetica chimica acta》2003,86(4):905-921
An extensive study and analysis of the concepts, classification, presentation, and nomenclature of chirality and lack of chirality in crystal structures and their constituents is presented. Oriented crystal structures are classified. The chirality rules for existence of molecular crystal structures are examined and the relation to segmentation and latent symmetry highlighted. The nomenclature of chirality and related terms, and the relationship of chirality to optical activity is covered. The uses and limitations of the Euclidean normalizer are treated. An improved glossary of terms is included. 相似文献
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[reaction: see text] Grubbs catalyst, Cl2(Cy3P)2Ru=CHPh, was found to catalyze the cross-metathesis of monosubstituted allenes to 1,3-disubstituted allenes in varying yields. 相似文献
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Richard Ian Cooper David John Watkin Howard D. Flack 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(4):261-267
A study of post‐refinement absolute structure determination using previously published data was carried out using the CRYSTALS software package. We show that absolute structure determination may be carried out optimally using the analyses available in CRYSTALS, and that it is not necessary to have the separate procedures absolute structure determination and no interest in absolute structure as proposed by Flack [Chimia (2014), 68 , 26–30]. 相似文献
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Theodore Flack Thibaut Constantin Sylvain Penasse Dr. Jérôme Dejeu Béatrice Gennaro Dr. Muriel Jourdan Aurélien Laguerre Marc Pirrotta Dr. David Monchaud Dr. Nicolas Spinelli Prof. Eric Defrancq 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(5):1760-1767
A water‐soluble template‐assembled synthetic G‐quartet (TASQ) based on the use of a macrocyclodecapeptide scaffold was designed to display stable intramolecular folds alone in solution. The preformation of the guanine quartet, demonstrated by NMR and CD investigations, results in enhanced peroxidase‐type biocatalytic activities and improved quadruplex‐interacting properties. Comparison of its DNAzyme‐boosting properties with the ones of previously published TASQ revealed that, nowadays, it is the best DNAzyme‐boosting agent. 相似文献
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The cross-correlation between surface temperature and subsurface velocity is presented for water undergoing evaporative convection.
The surface temperature measurements were obtained via quantitative infrared imaging, and the velocity measurements were obtained
using a two-component laser Doppler velocimetry (LDV) system. The water surface was covered with a surfactant monolayer, which
did not impede evaporation. The largest measured correlation coefficient was 0.375. Correlation coefficients obtained after
shifting the velocity and temperature time traces with respect to each other revealed a peak in the correlation coefficient
very close to a zero time shift. The significance of these results and their implications for the remote sensing of underwater
objects via infrared imaging are discussed.
Received: 2 April 2001/Accepted: 30 November 2001 相似文献
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This critical review provides a systematic classification of the synthetic routes to planar-chiral five-membered metallacycles into several routes, namely C-H bond activation, oxidative addition, transmetallation and optical resolution. As a characteristic of these bulk compounds is that they are synthesized as binary mixtures of enantiomers in proportions varying from the racemate to enantiopure, a review of absolute-configuration determination of the title planar-chiral scalemates is presented. This review is of interest to organic and organometallic synthetic chemists involved in asymmetric synthesis (97 references). 相似文献