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121.
A. Chaston Chapmann Hlasiwetz Nietzke und Petri 《Fresenius' Journal of Analytical Chemistry》1912,51(7-8):513-514
Ohne Zusammenfassung 相似文献
122.
K. Micko G. Kappeler R. Schulze und W. Petri 《Fresenius' Journal of Analytical Chemistry》1913,52(7-8):499-504
Ohne Zusammenfassung 相似文献
123.
K. Petri 《Mathematische Annalen》1923,88(3-4):242-289
Ohne Zusammenfassung 相似文献
124.
Lionello Petri 《Colloid and polymer science》1926,39(1):63-67
Ohne Zusammenfassung 相似文献
125.
P. Drescher H. G. Andresen K. Aulenbacher J. Bermuth Th. Dombol H. Fischerz H. Euteneuer N. N. Faleev M. S. Galaktionov D. v. Harrach P. Hartmann J. Hoffmann P. Jennewein K. H. Kaiser S. Köbis O. V. Kovalenkov H. J. Kreide J. Langbeine Y. A. Mamaev Ch. Nachtigall M. Petri S. Plützer E. Reicherte M. Schemies H. -J. Schöpe K. -H. Steffens M. Steigerwald A. V. Subashiev H. Trautner D. A. Vinokurov Y. P. Yashin B. S. Yavich 《Applied Physics A: Materials Science & Processing》1996,63(2):203-206
Strained layer GaAs.95P.05 photo cathodes are presented, which emit electron beams spinpolarized to a degree of P = 75% typically. Quantum yields around QE = 0.4% are observed routinely. The figure of merit P2 × QE = 2.3 × 10–3 is comparable to that of the best strained layer cathodes reported in literature. The optimum wavelength of irradiating light around 830 nm is in convenient reach of Ti:sapphire lasers or diode lasers respectively. The cathodes are produced using MOCVD-techniques. A GaAs.55P.45-GaAs.85P.15 superlattice structure prevents the migration of dislocations from the substrate and bottom layers to the strained overlayer. The surface is protected by an arsenic layer so that no chemical cleaning is necessary before installation into vacuum. The source of polarized electrons attached to the Mainz race track microtron MAMI works with such cathodes now. More than 1000 hours beamtime have been performed successfully. 相似文献
126.
Summary In this paper we present a numerical study of the SFUR (self-filtering unstable resonator) cavity resonant modes and numerical
results are compared with the experimental data. The numerical code developed for analysing the SFUR cavity will also allow
for studying a wider class of resonators, and is therefore a very useful tool in designing new laser cavities. 相似文献
127.
A solution of the solar neutrino problem based on certain differences between T(opological) G(eometro) D(ynamics) and the standard model of the electroweak interactions is proposed. First, TGD predicts the existence of a right-handed neutrino inert with respect to ordinary electroweak interactions. Second, the generalization of the massless Dirac equation contains terms mixing differentM
4 chiralities, unlike the ordinary massless Dirac equation. This and the observation of anticorrelations of the solar neutrino flux with sunspot number suggest that solar neutrinos are transformed to right-handed neutrinos on the convective zone of the Sun. Third, the compactness ofCP
2 implies topological field quantization: space-time decomposes into regions, topological field quanta, characterized by a handful of vacuum quantum numbers. In particular, there are topological obstructions for the smooth global imbeddings of magnetic fields and the decomposition of the solar magnetic field into flux tubes is predicted. Finally, every electromagnetically neutral mass distribution is accompanied by a long-rangeZ
0 vacuum field. If the vacuum quantum numbers inside the flux tubes of the solar magnetic field are considerably smaller than in the normal phase, theZ
0 electric force becomes strong and implies Thomas precession for the spin of the lefthanded component of the neutrino. As a consequence, left-handed neutrinos are transformed to right-handed ones and the process is irreversible, since righthanded neutrinos do not couple toZ
0. 相似文献
128.
129.
Petri Kärhä Reijo Visuri Kirsti Leszczynski Farshid Manoochehrl Kari Jokela Erkki Ikonen 《Photochemistry and photobiology》1996,64(2):340-343
A novel method for calibrating the absolute responsivity of solar UV spectroradiometers has been developed and tested. The method is based on calibrated filter radiometers constructed from a detector, a precision aperture, a band-pass filter and devices for temperature stabilization. The filter radiometers utilize a trap detector with very low reflectance. The filter and the detector can therefore be characterized separately. As an example the detector-based calibration is compared at 312 nm wavelength with lamp-based calibration by measuring the irradiance of a deuterium lamp with both the filter radiometer and the lamp-calibrated spectroradiometer. The agreement between the results is at the level of 1%, well within the estimated uncertainties of both methods. 相似文献
130.
Electron energy-loss spectroscopy of epitaxial Al films shows a small, but well-established anisotropy of the plasmon dispersion. This cannot be explained within the random-phase approximation (RPA). Anisotropic electron exchange correlations, caused by the lattice pseudopotential, account qualitatively for the observed differences of dispersion. 相似文献