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61.
Christian R. Noe M. Knollmüller K. Dungler C. Miculka P. Gärtner 《Monatshefte für Chemie / Chemical Monthly》1991,122(8-9):705-718
Summary Acetals3 and4 of alkylthienylcarbinols1 were prepared using an enantiomerically pure lactol2. In the key step these compounds were desulfurized. After deprotection the target compounds7 andent-7 were obtained.
Herrn Prof. Dr. H. Oelschläger zum 70. Geburtstag gewidmet 相似文献
62.
T. Gleisberg F. Krauss C. G. Papadopoulos A. Schälicke S. Schumann 《The European Physical Journal C - Particles and Fields》2004,34(2):173-180
In this paper total cross sections for signals and backgrounds of top- and Higgs-production channels in e + e- collisions at a future linear collider are presented. All channels considered are characterized by the emergence of six-particle final states. The calculation takes into account the full set of tree-level amplitudes in each process. Two multi-purpose parton level generators, HELAC/PHEGAS and AMEGIC + + , are used, and their results are found to be in perfect agreement.Received: 26 November 2003, Revised: 15 January 2004, Published online: 3 March 2004 相似文献
63.
P. Cicman M. Francis J.D. Skalny S. Matejcik T.D. Märk 《Czechoslovak Journal of Physics》2003,53(3):181-190
The rate constant for dissociative electron attachment to ozone has been derived over the energy range from about 0 to 10 eV using recently measured and also corrected cross section data. The new rate constant data sets for two partial dissociative channels, as well as for the total dissociative electron attachment, are compared with previously reported values, and existing discrepancies are discussed. 相似文献
64.
Hyperfine Interactions - During batch sorption experiments of heavy metals on chlorite not only sorption reactions take place, but also reactions of chemical weathering leading to mineral... 相似文献
65.
Introduction to Hardy Spaces 总被引:1,自引:1,他引:0
H. Baumgärtel 《International Journal of Theoretical Physics》2003,42(10):2213-2223
Basic material from the theory of Hardy spaces is presented. The principle of positive energy representations is used as motivation to introduce these spaces. 相似文献
66.
67.
A calibration technique for the constant-temperature hot-wire anemometer is presented, which is based on traversing the probe
through the boundary layer of a flat plate while simultaneously performing fluctuation measurements. The free stream Mach
number was M = 2.54, and the Reynolds number Red, based on wire diameter, ranged from 9 to 23. A comparison of the sensitivity values obtained with the aid of such a calibration
procedure — under the condition of neglecting low temperature loadings (t<0.6) — agrees well with sensitivities determined with free-stream data-The use of a modified transfer function for correcting
the power spectra of flow perturbations revealed a conformity of wide parts of the corrected spectra with the Kolmogorov decay.
The fluctuation levels of total temperature and mass flux were computed for the boundary layer of a flat plate.
This work was presented at the International Conference on the Methods of Aerophysical Research ICMAR 2007, which was held
in Novosibirsk on 5–10 February 2007. 相似文献
68.
Let R be a local ring and let (x
1, …, x
r) be part of a system of parameters of a finitely generated R-module M, where r < dimR
M. We will show that if (y
1, …, y
r) is part of a reducing system of parameters of M with (y
1, …, y
r) M = (x
1, …, x
r) M then (x
1, …, x
r) is already reducing. Moreover, there is such a part of a reducing system of parameters of M iff for all primes P ε Supp M ∩ V
R(x
1, …, x
r) with dimR
R/P = dimR
M − r the localization M
P of M at P is an r-dimensional Cohen-Macaulay module over R
P.
Furthermore, we will show that M is a Cohen-Macaulay module iff y
d is a non zero divisor on M/(y
1, …, y
d−1) M, where (y
1, …, y
d) is a reducing system of parameters of M (d:= dimR
M). 相似文献
69.
70.
J. Walz S. B. Ross C. Zimmermann L. Ricci M. Prevedelli T. W. Hänsch 《Hyperfine Interactions》1996,100(1):133-144
Experiments with electrons and ions in a combined trap are reported. The unique capability to confine particles with opposite charge and very different mass simultaneously in the same spatial region makes the combined trap a promising device for future synthesis of antihydrogen. 相似文献