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441.
442.
U. Kasper 《Annalen der Physik》1973,485(2):147-154
We consider the connection between EINSTEIN 's, v. FREUD 's, and MØLLER 's views concerning the energy-momentum problem. First we generalize MØLLER 's expressions in such a way that the tetrad need not be orthonormalized. Then we mark out a covering of space-time with holonomic tetrads in the sense given by SCHOUTEN . In case that the covering of space-time with natural bases used to give the components of all quantities, is identical with the marked out covering of space-time with holonomic tetrads, we obtain from the generalized MØLLER 's expressions the well known ones given by EINSTEIN and v. FREUD . 相似文献
443.
The thermal decomposition of Nafion has been studied by means of high-resolution and constant heating rate thermogravimetry
(TG), under nitrogen and synthetic air atmospheres. Nafion membranes have been studied in acid and salt (alkali chlorides)
forms. The TG curves of Nafion with alkali countercations show similar profiles, whichever the atmosphere employed. The kinetics
of thermal decomposition of the Nafion-Cs+ has also been studied. The method employed to calculate the kinetic parameters and to estimate the polymer lifetime from
the data was based on Kissinger's method.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
444.
The gauge theory dual to the decay of an unstable D-particle in AdS is analysed in terms of coherent states. We discuss in detail how to count the number of particles in the decay product. We find, in agreement with the analysis in flat space, that the emission amplitude is suppressed as the mass of the radiated particles increases. To cite this article: M. Zamaklar, K. Peeters, C. R. Physique 5 (2004).
Résumé
La théorie de jauge duale à la désintégration de D-particules instables dans AdS est analysée en termes d'état cohérents. Nous discutons en détails le comptage du nombre de particule dans le produit de désintégration. Nous trouvons, en accord avec l'analyse en espace plat, que le taux d'émission est supprimé quand la masse de la particule augmente. Pour citer cet article : M. Zamaklar, K. Peeters, C. R. Physique 5 (2004). 相似文献445.
Applying MRI techniques to low-density fibrous filter media provides us with unique information about the initial structure and deposited mass within the same filter sample. This now enables us to obtain the necessary link between structure and deposition for validation and further enhancement of modeling filtration kinetics. However, additional work is needed before achieving a realistic understanding of filtration kinetics. 相似文献
446.
Aitala EM Amato S Anjos JC Appel JA Ashery D Banerjee S Bediaga I Blaylock G Bracker SB Burchat PR Burnstein RA Carter T Carvalho HS Copty NK Cremaldi LM Darling C Denisenko K Devmal S Fernandez A Fox GF Gagnon P Gobel C Gounder K Halling AM Herrera G Hurvits G James C Kasper PA Kwan S Langs DC Leslie J Lundberg B Magnin J Massafferri A MayTal-Beck S Meadows B de Mello Neto JR Mihalcea D Milburn RH de Miranda JM Napier A Nguyen A d'Oliveira AB O'Shaughnessy K Peng KC Perera LP Purohit MV 《Physical review letters》2001,86(5):765-769
From a sample of 848+/-44 D(+)(s)-->pi(-)pi(+)pi(+) decays, we find gamma(D(+)(s)-->pi(-)pi(+)pi(+))/gamma(D(+)(s)-->straight phipi(+)) = 0.245+/-0.028(+0.019)(-0.012). Using a Dalitz plot analysis of this three body decay, we find significant contributions from the channels rho(0)(770)pi(+), rho(0)(1450)pi(+), f(0)(980)pi(+), f(2)(1270)pi(+), and f(0)(1370)pi(+). We also present the values obtained for masses and widths of the resonances f(0)(980) and f(0)(1370). 相似文献
447.
J. F. Luy H. Kibbel E. Kasper 《International Journal of Infrared and Millimeter Waves》1986,7(3):305-315
CW-IMPATT diodes for W-band operation are fabricated from Silicon Molecular Beam Epitaxy material. Using different preparation techniques, the active layer of single drift structures is grown at 750 °C and 550 °C. Doping is performed by molecular beams from Sb (n-type) or Ga (p-type) effusion cells. The influence of the p+-doping level on the series resistance of the diode is investigated. Measurements of efficiency as a function of the active region data deliver fine design rules. The output power is 450 mW at 87 GHz from diodes mounted in a hermetically sealed package on a diamond heat sink. 相似文献
448.
Uwe Kasper 《General Relativity and Gravitation》1985,17(8):725-738
In the framework of classical field theory, we try to explain why the effective cosmological constant is so small. The basis of the attempt is a Higgs field that shall determine the global structure of the universe. Einstein's theory of gravitation does not allow one to realize the idea. But we are successful if we start from some variant of the scalar-tensor theory of gravitation, choosing for the parameters that enter the Lagrangean of the Higgs field the Compton length of a proton and Eddington's number as self-coupling constant. 相似文献
449.
Aitala EM Amato S Anjos JC Appel JA Ashery D Banerjee S Bediaga I Blaylock G Bracker SB Burchat PR Burnstein RA Carter T Carvalho HS Copty NK Cremaldi LM Darling C Denisenko K Devmal S Fernandez A Fox GF Gagnon P Gobel C Gounder K Halling AM Herrera G Hurvits G James C Kasper PA Kwan S Langs DC Leslie J Lundberg B Magnin J MayTal-Beck S Meadows B de Mello Neto JR Mihalcea D Milburn RH de Miranda JM Napier A Nguyen A d'Oliveira AB O'Shaughnessy K Peng KC Perera LP Purohit MV Quinn B Radeztsky S 《Physical review letters》2001,86(18):3969-3972
We report results of a search for flavor-changing neutral current (FCNC), lepton flavor, and lepton-number violating decays of the D0 (and its antiparticle) into three and four bodies. Using data from Fermilab charm hadroproduction experiment E791, we examine modes with two leptons (muons or electrons) and a rho(0), K( *0), or straight phi vector meson or a nonresonant pi(pi), Kpi, or KK pair of pseudoscalar mesons. No evidence for any of these decays is found. Therefore, we present branching-fraction upper limits at 90% confidence level for the 27 decay modes examined (18 new). 相似文献
450.
Wilson LB Cattell C Kellogg PJ Goetz K Kersten K Hanson L MacGregor R Kasper JC 《Physical review letters》2007,99(4):041101
We describe results from the first statistical study of waveform capture data during 67 interplanetary (IP) shocks with Mach numbers ranging from approximately 1-6. Most of the waveform captures and nearly 100% of the large amplitude waves were in the ramp region. Although solitary waves, Langmuir waves, and ion acoustic waves (IAWs) are all observed in the ramp region of the IP shocks, large amplitude IAWs dominate. The wave amplitude is correlated with the fast mode Mach number and with the shock strength. The observed waves produced anomalous resistivities from approximately 1-856 Omega.m (approximately 10(7) times greater than classical estimates.) The results are consistent with theory suggesting IAWs provide the primary dissipation for low Mach number shocks. 相似文献