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151.
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154.
Erich Müller 《Colloid and polymer science》1911,8(6):302-303
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Erich Müller und Kurt Mehlhorn 《Fresenius' Journal of Analytical Chemistry》1934,96(5-6):173-175
Ohne Zusammenfassung 相似文献
157.
Marcus Wingen Karl‐Erich Jaeger Thomas Gensch Thomas Drepper 《Photochemistry and photobiology》2017,93(3):849-856
Flavin‐binding fluorescent proteins (FbFPs) are small, oxygen‐independent in vivo reporters, derived from Light Oxygen Voltage (LOV) domains of photoreceptors. Here, we investigated the thermostability of existing, as well as novel FbFPs, whose genes were identified in genome sequences of various thermophilic bacteria as well as metagenomic libraries from hot springs in the Yellowstone National Park. Detailed in vitro analyses revealed that two of those fluorescent reporter proteins were highly thermostable, exhibiting melting temperatures above 75°C. 相似文献
158.
The push-pull characters of a large series of donor-acceptor substituted azo dyes—71 structures in all—have been quantified by the NN double bond lengths, dNN, the 15N NMR chemical shift differences, Δδ15N, of the two nitrogen atoms and the quotient, π∗/π, of the occupations of the antibonding π∗, and bonding π orbitals of this partial NN double bond. The excellent correlation of the occupation quotients with the bond lengths strongly infers that both π∗/π and dNN are excellent parameters for quantifying charge alternation in the push-pull chromophore and the molecular hyperpolarizability, β0, of these compounds. By this approach, selected compounds can be appropriately considered as viable candidates for nonlinear optical (NLO) applications. 相似文献
159.
Rahul S. Pawar Erich Grundel Eugene Mazzola Kevin D. White Alexander J. Krynitsky Jeanne I. Rader 《Journal of separation science》2010,33(2):200-205
Enantioseparation of the pyrrolizidine alkaloid isomers intermedine and lycopsamine, isolated from Symphytum uplandicum, is discussed. The separatory power of two immobilized carbohydrate‐based chiral HPLC columns, Chiralpak IA and IC, in different chromatographic conditions is compared. The study demonstrated the importance of solvent and column selection while developing such chiral HPLC separation methods. The baseline HPLC separation of the two alkaloid isomers in preparatory scale is reported for the first time. The optimized separations were achieved on a Chiralpak IA column with mobile phases of ACN/methanol (80:20) and methanol/methyl‐t‐butyl ether (90:10), both containing 0.1% diethylamine. 相似文献
160.
The conformational analyses of six non-rigid N-acetyl glucosamine (NAG) derivatives employing residual dipolar couplings (RDCs) and NOEs together with molecular dynamics (MD) simulations are presented. Due to internal dynamics we had to consider different conformer ratios existing in solution. The good quality of the correlation between theoretically and experimentally obtained RDCs show the correctness of the calculated conformers even if the ratios derived from the MD simulations do not exactly meet the experimental data. If possible, the results were compared to former published data and commented. 相似文献