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71.
72.
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   
73.
Reuther  H.  Arnold  T.  Krawczyk-Bärsch  E. 《Hyperfine Interactions》2004,156(1-4):439-443
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   
74.
The sound propagation into a courtyard shielded from direct exposure is predicted using an equivalent sources approach. The problem is simplified into that of a two-dimensional city canyon. A set of equivalent sources are used to couple the free half-space above the canyon to the cavity inside the canyon. Atmospheric turbulence causes an increase in the expected value of the sound pressure level compared to a homogeneous case. The level increase is estimated using a von Kármán turbulence model and the mutual coherences of all equivalent sources' contributions. For low frequencies the increase is negligible, but at 1.6 kHz it reaches 2-5 dB for the geometries and turbulence parameters used here. A comparison with a ray-based model shows reasonably good agreement.  相似文献   
75.
Introduction to Hardy Spaces   总被引:1,自引:1,他引:0  
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   
76.
77.
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   
78.
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 MV 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   
79.
80.
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   
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