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61.
Grzegorz Mlostoń Paulina Mucha Katarzyna Urbaniak Karolina Broda Heinz Heimgartner 《Helvetica chimica acta》2008,91(2):232-238
The three‐component reaction of (R)‐ or (S)‐1‐phenylethylamine ( 6 ), formaldehyde, and an α‐(hydroxyimino) ketone 5 , i.e., 3‐(hydroxyimino)butan‐2‐one ( 5a ) or 2‐(hydroxyimino)‐1,2‐diphenylethanone ( 5b ), yields the corresponding enantiomerically pure 1‐(1‐phenylethyl)‐1H‐imidazole 3‐oxide 7 in high yield (Schemes 2 and 3). The reactions are carried out either in MeOH or in AcOH. Smooth transformations of the N‐oxides into optically active 1‐(1‐phenylethyl)‐1H‐imidazoles 10 and 2,3‐dihydro‐1‐(1‐phenylethyl)‐1H‐imidazole‐2‐thiones 11 are achieved by treatment of 7 with Raney‐Ni and 2,2,4,4‐tetramethyl‐3‐thioxocyclobutanone ( 12 ), respectively (Scheme 4). 相似文献
62.
A theoretical investigation on the planarity of molecular structure of zinc phthalocyanine (ZnPc) and its aromaticity has been performed using B3LYP and M06-2X density functionals combined with selected Pople-type basis sets. The effect of the applied calculation method on the optimized structure of ZnPc and ZnPc???H2O, both in the gas phase and in the polar solvent, was analyzed. To quantify the aromaticity of the ZnPc and ZnPc???H2O complexes, both the geometric and magnetic criteria, i.e., Harmonic Oscillator Model of Aromaticity (HOMA) index and the nucleus-independent chemical shift (NICS) values at the centers or 1 Å above the centers of structural subunits, were calculated. The energies of highest energy occupied molecular orbital (HOMO) and lowest energy unoccupied molecular orbital (LUMO) and energy gaps were also estimated. The results show that the free ZnPC molecule is flat in the gas phase and nonplanar in the polar environments (DMSO and water). ZnPC???H2O is nonpolar in the gas phase and polar solvent which is in agreement with recent X-ray reports. Both HOMA and NICS indexes indicate the presence of highly aromatic macrocycle and benzene rings while these parameters for pyrrolic ring are significantly smaller than in free pyrrole. The presence of polar solvents practically does not change aromaticity of the ring subunits of the studied compounds. 相似文献
63.
Zusammenfassung Die Verteilung des Radioarsens über seine beiden Oxydationsstufen nach Bestrahlung von gelöstem und festem Arsenit und Arsenat mit langsamen Neutronen wurde bestimmt.Diese Verteilung erwies sich bei Bestrahlung von Lösungen der beiden Ionen als praktisch unabhängig von der Konzentration, dem pH-Wert und der Temperatur.Dagegen ergab sich ein vergrößerter Anteil an Radio-AsV, wenn festes Arsenat oder Arsenit mit schnellen statt langsamen Neutronen aktiviert wurde.Es wird geschlossen, daß im Gegensatz zu den Verhältnissen beim Permanganation die Wertigkeit des Radioarsens bereits in der Primärreaktion bestimmt wird, das heißt, während der Explosion des Ions nach Einfang des Neutrons.Mit 2 Abbildungen. 相似文献
64.
Zusammenfassung Ein Verfahren zur Gewinnung von reinen Radiozuckern sehr hoher Aktivität ohne Verwendung inaktiver Träger wird beschrieben. Grüne Blätter werden zur Assimilation von Radiokohlensäure veranlaßt. Sodann werden die Blätter mit Alkohol und Wasser extrahiert. Der alkoholische Extrakt wird mit Äther und Wasser geschieden, der wäßrige Extrakt hydrolysiert. Darauf werden beide Extrakte mit Ionenaustauschern gereinigt und papierchromatographisch auf reine Glukose und Fruktose aufgearbeitet. Die spezifische Aktivität der derart gereinigten Glukose beträgt bis zu 63·106, der Fruktose bis zu 30·106 Zerfälle/Min. mg. Dies dürften bei weitem die höchstaktiven Zucker sein, deren Darstellung in der Literatur beschrieben worden ist.Mit 2 Abbildungen. 相似文献
65.
C. T. Zhang R. Broda R. Menegazzo P. Kleinheinz R. Collatz H. Grawe S. Hofmann M. Lach K. H. Maier M. Schramm R. Schubart J. Blomqvist 《Zeitschrift für Physik A Hadrons and Nuclei》1993,345(3):327-328
The N=84 nucleus154Yb was investigated through the106Cd(54Fe,2p) reaction. We found the 16+ yrast level in this nucleus to be formed by the (h11/2
2
f7/2h9/2) configuration, in contrast to the lower-Z isotones where (h11/2
2
f7/2
2)16+ is the yrast state. Manybody shell model calculations with empirical two-body interactions support our conclusion.Dedicated to Prof. Dr. O. Schult on the occasion of his 60th birthday 相似文献
66.
M. Schramm H. Grawe J. Heese H. Kluge K. H. Maier R. Schubart R. Broda J. Grebosz W. Krolas A. Maj J. Blomqvist 《Zeitschrift für Physik A Hadrons and Nuclei》1993,344(4):363-367
208Pb has been excited with inelastic heavy ion scattering of 350 MeV64Ni and 420 MeV82Se on a thick208Pb target. With - coincidence measurements 2 new decays of the 10+ isomer, namely a 34.5 keVE2-transition to 8
2
+
and a 857.7 keVE3 transition to 7– have been found and the wavefunctions of the participating levels deduced. An observed gamma cascade of 295.3, 348.0, 865.4 and 340.2 keV on top of the 10+ isomer is assigned to the particle-hole states with the highest spins 14– 6744.1 keV13– 6448.9 keV12+ 6100.9 keV11+ 5235.6 keV10+ 4895.4 keV.This work has been supported in part through the agreement on scientific cooperation between Poland and Germany. 相似文献
67.
68.
R. Broda P. J. Daly J. H. McNeill Z. W. Grabowski R. V. F. Janssens R. D. Lawson D. C. Radford 《Zeitschrift für Physik A Hadrons and Nuclei》1989,334(1):11-17
Following reactions induced by 245 MeV60Ni ions, isomers have been identified in the odd-oddN=81 isotones146Tb,148Ho and150Tm with half-lives of 1.18(2), 2.35(4) and 5.2(3) ms, respectively. Their decays have been characterized byγ-ray spectroscopy. The isomers are interpreted as (πh 11/2 νh 1 2/?1 ) 10+ states decaying to members ofπh 11/2 νd 3 2/?1 andπh 11 2/?1 multiplets. The observed level spectra and M1 branching ratios are found to be in good agreement with shell model predictions based on empirical and Schiffer-Trueπν ?1 residual interactions. 相似文献
69.
J. Wrzesiński K.H. Maier R. Broda B. Fornal W. Królas T. Pawłat D. Bazzacco S. Lunardi C. Rossi Alvarez G. de Angelis A. Gadea J. Gerl M. Rejmund 《The European Physical Journal A - Hadrons and Nuclei》2001,10(3):259-265
High-spin states in 208Pb have been studied by γ-ray-spectroscopy methods in deep inelastic reactions induced by beams of 208Pb, 136Xe and 76Ge beams on a thick 208Pb target. The 11+
2 state and new γ-transitions between the one-particle one-hole states of highest spin have been found and electromagnetic
matrix elements verified. High-spin states of two-particle two-hole structure have been detected for the first time. The results
are compared to shell model calculations with realistic interactions in the complete Kuo-Herling space.
Received: 31 October 2000 / Accepted: 26 March 2001 相似文献
70.
Electron density fluctuations as well as current density correlations are considered for excited nano plasmas. Calculations are performed by classical MD simulations at high temperatures for expanding nearly spherical clusters of laser irradiated sodium atoms. The resonance structures observed in the frequency spectrum of the bi‐local correlation functions are analyzed. Mie modes and volume plasmon type excitations are observed as well as breathing modes. We investigate the relation between the bi‐local correlation functions of the electron density fluctuations and current density via the equation of continuity.The collective excitations are of significance for the dielectric function and further properties such as the photo absorption coefficients. Results are presented for an exemplarily taken set of parameter values of the nano plasma (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献