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71.
P. Eberhardt O. Eugster J. Geiss H. Graf N. Grögler und H. Schwaller 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1972,23(3):509
Ohne Zusammenfassung 相似文献
72.
73.
Andreas J. Steiner Georg Schitter Arnold E. Stütz Tanja M. Wrodnigg Chris A. Tarling Stephen G. Withers Don J. Mahuran Michael B. Tropak 《Tetrahedron: Asymmetry》2009,20(6-8):832-835
Cyclisation by double reductive amination of 2-acetamino-2-deoxy-d-xylo-hexos-5-ulose with N-2 protected l-lysine derivatives provided 2-acetamino-1,2-dideoxynojirimycin derivatives without any observable epimer formation at C-5. Modifications on the lysine moiety gave access to lipophilic derivatives that exhibited improved hexosaminidase inhibitory activities. 相似文献
74.
Wilhelm Graf 《Colloid and polymer science》1916,19(4):165-172
Ohne Zusammenfassung 相似文献
75.
Ohne Zusammenfassung 相似文献
76.
J. Augustin St. Graf B. Müller W. Greiner 《Zeitschrift für Physik A Hadrons and Nuclei》1990,336(3):353-356
The rates forX ° creation by photons and electrons channeling along a crystal axis are estimated. The process is found to depend strongly on the parameters of the crystal fields. PromisingX ° production rates can therefore be obtained for germanium rather than for lighter elements. 相似文献
77.
78.
Ümit Akbey Robert Graf Yuan G. Peng Peter P. Chu Hans W. Spiess 《Journal of Polymer Science.Polymer Physics》2009,47(2):138-155
NMR studies of the structure and dynamics of a system composed of the acidic polymer poly(acrylic acid) (PAA) and the basic polymer poly(4‐vinyl pyridine) (P4VP) are presented. This system aims at the application of anhydrous proton‐conducting membranes that can be used at elevated temperatures at which the proton conduction of hydrated membranes breaks down. The 1H NMR measurements have been preformed under fast magic angle spinning (MAS) conditions to achieve sufficient resolution and the applied 1H NMR methods vary from simple 1H MAS to double‐quantum filtered methods and two‐dimensional 1H double‐quantum spectroscopy. The dynamic behavior of the systems has been investigated via variable temperature 1H MAS NMR. 13C cross‐polarization MAS NMR provides additional aspects of dynamic and structural features to complete the picture. Different types of acidic protons have been identified in the studied PAA‐P4VP systems that are nonhydrogen‐bonded free acidic protons, hydrogen‐bonded dicarboxylic dimers, and protons forming hydrogen bonds between carboxylic protons and ring nitrogens. The conversion of dimer structures in dried PAA to free carboxylic acid groups is accomplished at temperatures above 380 K. However, the stability of hydrogen‐bonding strongly depends on the hydration level of the polymer systems. The effect of hydration becomes less apparent in the complexes. An inverse proportionality between hydrogen‐bonding strength and proton conduction in the PAA‐P4VP acid–base polymer blend systems was established. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 138–155, 2009 相似文献
79.
Cyclometalated Iridium(III) and Rhodium(III) Complexes Containing Naphthyridine Ligands: Synthesis,Characterization and Biological Studies
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The synthesis, crystal structure, and biological activity of new bis‐cyclometalated compounds [M(ptpy)2(4‐chloro‐2‐methyl‐1,8‐naphthyridine)]PF6 [M = Rh ( 1 ); M = Ir ( 2 ); ptpy = 2‐(p‐tolyl)pyridinato] and [M(ptpy)2(2‐methyl‐1,8‐naphthyridine)]PF6 [M = Rh ( 3 ); M = Ir ( 4 )] are described. The new compounds were prepared by the reaction of [{M(μ‐Cl)(ptpy)2}2] (M = Rh, Ir) with the corresponding naphthyridine ligands. The molecular structures of compounds 1 , 3 , and 4 were confirmed by single‐crystal X‐ray diffraction studies. 相似文献
80.
Flavin Adenine Dinucleotide and N5,N10‐Methenyltetrahydrofolate are the in planta Cofactors of Arabidopsis thaliana Cryptochrome 3
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Tanja Göbel Stefan Reisbacher Alfred Batschauer Richard Pokorny 《Photochemistry and photobiology》2017,93(1):355-362
Members of the cryptochrome/photolyase family (CPF) of proteins utilize noncovalently bound light‐absorbing cofactors for their biological function. Usually, the identity of these cofactors is determined after expression in heterologous systems leaving the question unanswered whether these cofactors are identical to the indigenous ones. Here, cryptochrome 3 from Arabidopsis thaliana was expressed as a fusion with the green fluorescent protein in Arabidopsis plants. Besides the confirmation of the earlier report of its localization in chloroplasts, our data indicate that fractions of the fusion protein are present in the stroma and associated with thylakoids, respectively. Furthermore, it is shown that the fusion protein expressed in planta contains the same cofactors as the His6‐tagged protein expressed in Escherichia coli, that is, flavin adenine dinucleotide and N5,N10‐methenyltetrahydrofolate. This demonstrates that the heterologously expressed cryptochrome 3, characterized in a number of previous studies, is a valid surrogate of the corresponding protein expressed in plants. To our knowledge, this is also a first conclusive analysis of cofactors bound to an Arabidopsis protein belonging to the CPF and purified from plant tissue. 相似文献