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141.
Lange HR Grillon G Ripoche JF Franco MA Lamouroux B Prade BS Mysyrowicz A Nibbering ET Chiron A 《Optics letters》1998,23(2):120-122
Self-guided propagation of femtosecond laser pulses is studied for a converging-beam configuration. Channeling of the pulse energy through various gases is observed over distances well beyond the lens focal point, a fact that cannot be explained by the moving-focus model. The results are in good agreement with three-dimensional numerical simulations. 相似文献
142.
143.
D. Holde W. Stauf H. Mallison Albrecht Wolff E. Lazló Wo Ostwald R. Auerbacht C. E. Fawkes G. Gallo M. Tenani J. Duclaux J. Errera G. Meyerheim F. Frank H. Vogel S. Erk R. Ditmar R. Fischer E. P. Bauer K. Albert H. J. Schulz H. W. Klever E. Berl M. Isler A. Lange J. Traube J. Magasanik F. V. von Hahn D. Krüger E. C. Bingham R. F. Jackson E. von Mülendahl 《Analytical and bioanalytical chemistry》1930,82(4-5):163-176
144.
Heiko Lange Klaus Bergander Dr. Roland Fröhlich Dr. Seda Kehr Dr. Shuichi Nakamura Prof. Dr. Norio Shibata Prof. Dr. Takeshi Toru Prof. Dr. Dieter Hoppe Prof. Dr. 《化学:亚洲杂志》2008,3(1):88-101
Substitution reactions that employ primary‐carbamoyl‐protected arylmethanethiols are described. The enantiodetermining step was found to occur in the post‐deprotonation step as a dynamic thermodynamic resolution with a chiral bis(oxazoline) ligand. The configurationally labile lithium complexes were trapped with various electrophiles to yield different substitution products in good to excellent yields and enantiomeric excesses. The absolute configurations of the substitution products were determined, and the stereochemical pathway of the substitution reaction was elucidated for different classes of electrophiles. The temperature‐dependent epimerization process was monitored by 1H and 6Li NMR spectroscopy. 相似文献
145.
Pound G McKenzie JM Lange RF Klumperman B 《Chemical communications (Cambridge, England)》2008,(27):3193-3195
Aldehyde omega-endfunctional poly(N-vinylpyrrolidone) was synthesised via quantitative conversion of a xanthate endfunctional precursor obtained via RAFT-mediated polymerisation. 相似文献
146.
Adri van den Hoogenband Jos H.M. Lange Melle Koch Martin Visser Johann T.B.H. Jastrzebski 《Tetrahedron letters》2008,49(26):4122-4124
A Ruphos-mediated Suzuki cross-coupling between (hetero)aryl bromides and secondary alkyltrifluoroborates is described using palladium catalysis. The Ruphos ligand showed superior properties as compared to S-Phos in this type of reaction. This method constitutes a valuable extension to current methods for the straightforward production of secondary-alkylated (hetero)aryl derivatives. 相似文献
147.
148.
149.
Schneider R Ader C Lange A Giller K Hornig S Pongs O Becker S Baldus M 《Journal of the American Chemical Society》2008,130(23):7427-7435
We show that solid-state NMR can be used to investigate the structure and dynamics of a chimeric potassium channel, KcsA-Kv1.3, in lipid bilayers. Sequential resonance assignments were obtained using a combination of (15)N- (13)C and (13)C- (13)C correlation experiments conducted on fully labeled and reverse-labeled as well as C-terminally truncated samples. Comparison of our results with those from X-ray crystallography and solution-state NMR in micelles on the closely related KcsA K (+) channel provides insight into the mechanism of ion channel selectivity and underlines the important role of the lipid environment for membrane protein structure and function. 相似文献
150.
We construct the coarse moduli space of quadratic line complexes with a fixed Segre symbol σ as well as the moduli space of the corresponding singular surfaces. We show that the map associating to a quadratic line complex its singular surface
induces a morphism . Finally we deduce that the varieties of cosingular quadratic line complexes are almost always curves.
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