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991.
992.
Christian Hess 《Set-Valued Analysis》2007,15(1):1-20
Integration of set-valued maps (alias multifunctions) depending on a parameter is revisited. Results of Artstein, and of Saint-Pierre
and Sajid are extended to the case of set-valued maps whose values may be unbounded. In the general case, this is achieved
assuming that the transition probabilities involved in the integration procedure are absolutely continuous with respect to
some fixed probability measure. However, when the integrating probability measure does not depend on the parameter this hypothesis
is shown to be unnecessary. On the other hand, an alternative proof of a result of Saint-Pierre and Sajid is provided for
convex compact-valued multifunctions. An application is given to the control of chattering systems. It is an extension of
a result of Artstein to the case of set-valued maps with unbounded values. The proof of the main results is simple and essentially
relies on measurable selections arguments.
相似文献
993.
994.
A. Kumar S. Trotsenko A. V. Volotka D. Bana? H. F. Beyer H. Br?uning A. Gumberidze S. Hagmann S. Hess C. Kozhuharov R. Reuschl U. Spillmann M. Trassinelli G. Weber Th. St?hlker 《The European physical journal. Special topics》2009,169(1):19-22
The two-photon 2E1 transition from the singlet 2s state of heliumlike tin was measured. An alternative experimental approach
was adopted in the present investigation where the two-photon emission results from the decay of the 2s state by selective
K-shell ionization of Li-like tin ions in relativistic collisions with a low-Z gaseous target, which allowed for a measurement
of the undistorted two-photon spectral shape. The measured 2E1 energy distribution was compared with fully relativistic calculations,
which predict a Z dependence of the distribution. The preliminary results indicate the best agreement with the relativistic many body calculations for tin, and thus confirm the sensitivity
on Z. Detailed data analysis is still in progress. 相似文献
995.
Edmund Hess 《Mathematische Annalen》1886,28(2):167-260
Ohne Zusammenfassung 相似文献
996.
Filipp Hess 《Fresenius' Journal of Analytical Chemistry》1880,19(1):504
Ohne Zusammenfassung 相似文献
997.
998.
F. Jostes W. Hess C. A. Bouman A. R. Rescorla F. L. Carnahan M. R. Fenske und S. Fischer 《Fresenius' Journal of Analytical Chemistry》1940,120(3-4):136-140
Ohne Zusammenfassung 相似文献
999.
W. Prandtl A. Brukl L. Pauling H. N. Mc Coy Ida Noddack J. K. Marsh L. Holleck W. Noddack G. Urbain F. Bourion G. Jantsch H. Albers H. Grubitsch P. W. Selwood J. A. C. Bowles H. M. Partridge H. C. Fogg L. Hess H. H. Williard N. K. Tang E. A. Werner C. James H. C. Holden A. J. Grant J. P. Bonardi Leonid Kuhlberg und F. M. Semiakin 《Fresenius' Journal of Analytical Chemistry》1938,113(3-4):121-135
Ohne Zusammenfassung 相似文献
1000.
Dialysis was evaluated as a non-destructive clean-up technique to isolate chlorobiphenyls (CBs) from fish-oil prior to further analysis. 14C-CBs were used to study the transfer processes of the CBs across polyethylene membranes. Single step processes using equilibrium dialysis were compared to a dynamic method of refluxing solvent. The dynamic method reduced the duration of the separation to 8 h. The transfer of CBs and the lipids was dependent on temperature and nature of the analyte with smaller molecules being dialysed substantially faster than larger molecules. An optimised dynamic method was used to compare the dialytic clean-up with a traditional method using sulfuric acid-impregnated silica for the determination of CBs in a laboratory reference material. Labelled recovery standards for each individual congener are recommended in combination with dialysis as a method for clean-up. 相似文献