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91.
Raúl Pérez-Ruiz Robert Fichtler Yrene Diaz Miara Matthieu Nicoul Dominik Schaniel Helfried Neumann Matthias Beller Dirk Blunk Axel G. Griesbeck Axel Jacobi von Wangelin 《Journal of fluorescence》2010,20(3):657-664
The photophysical properties of a series of structurally related 4-aminophthalimides and the corresponding 5-aminophthalic hydrazides (luminols) are reported. Absorption, steady-state, and time-resolved fluorescence spectra of luminols exhibited substitution, solvent, and pH dependence. Singlet lifetimes have been determined by time-resolved laser flash spectroscopy. UV spectra in gas phase and DMSO solution were calculated by TD-DFT which revealed the existence of two low-energy excited singlet states with strong pH-sensitivity. 相似文献
92.
93.
Costantino DJ Scheidemantel TJ Stone MB Conger C Klein K Lohr M Modig Z Schiffer P 《Physical review letters》2008,101(10):108001
We explore the process of initiating motion through a granular medium by measuring the force required to push a flat circular plate upward from underneath the medium. In contrast with previous measurements of the drag and penetration forces, which were conducted during steady state motion, the initiation force has a robust dependence on the diameter of the grains in the medium. We attribute this dependence to the requirement for local dilation of the grains around the circumference of the plate, as evidenced by an observed linear dependence of the initiation force on the plate diameter. 相似文献
94.
We study dc charge and spin transport through a weakly coupled quantum dot, driven by a nonadiabatic periodic change of system parameters. We generalize the model of Tien and Gordon to simultaneously oscillating voltages and tunnel couplings. When applying our general result to the two-parameter charge pumping in quantum dots, we find interference effects between the oscillations of the voltage and tunnel couplings. We show that these interference effects may explain recent measurements in metallic islands. Furthermore, we discuss the possibility to electrically pump a spin current in presence of a static magnetic field. 相似文献
95.
G. T. Jones B. W. Kennedy R. P. Middleton S. W. O'Neale A. M. Cooper A. Grant H. Klein J. Mittendorfer D. R. O. Morrison A. Parker P. Schmid H. Wachsmuth F. Hamisi M. M. Mobayyen O. Villalobos-Baillie M. Aderholz L. Deck N. Schmitz W. Wittek G. Corrigan G. Myatt D. Radojicic M. Retter 《Zeitschrift fur Physik C Particles and Fields》1984,25(2):121-127
Data from a neutrino and antineutrino hydrogen experiment with BEBC are used to investigate transverse properties of the produced charged hadrons. Measurements are presented on average transverse momenta of charged pions as functions of Feynman-x and the hadronic mass, on the transverse momentum flow within an event and on jet-related quantities. The main features of the data are well described by the LUND model. The data favour a version of the model in which soft gluon effects are included and the primordial transverse momentum of the quarks in the proton is small. Effects from 1st order QCD (hard gluon emission) are negligible. 相似文献
96.
An analysis is presented of the recent data which are sensitive to thee, μ and τ neutral current couplings. A fit combining all results (e + e ?, μC,ve, eD, atoms) selects a unique solution in agreement with the standard-model expectation. Assuming lepton universality, the vector and axial-vector couplings are determined to bev=?0.013±0.048 anda=?0.520±0.014. Similarly we find (sin2 θ=0.213±0.012,ρ=0.015±0.038) or (sin2 θ=0.211α0.012, ρ≡1 which, combined with all other values, gives an average of sin2 θ=0.216±0.006. 相似文献
97.
R. Kopp A. Argento A. C. Benvenuti D. Bollini G. Bruni T. Camporesi M. Cribier J. Cvach N. G. Fadeev J. Feltesse I. A. Golutvin M. Goossens G. Heiman D. Jamnik Y. T. Kiryushin V. S. Kisselev M. Klein V. G. Krivokhizhin V. V. Kukhtin W. Lohmann U. Meyer-Berkhout A. Milsztajn L. Monari F. L. Navarria W. D. Nowak A. Ouraou L. Piemontese P. Rich-Hennion Y. Sacquin I. A. Savin G. Smadja G. I. Smirnov A. Staude K. M. Teichert R. Tirler G. Todorova P. Todorov P. Verrecchia G. Vesztergombi M. Virchaux A. G. Volodko R. Voss J. Zacek Č. Zupančič BCDMS Collaboration 《Zeitschrift fur Physik C Particles and Fields》1985,28(2):171-174
98.
Characteristics of the adsorption of nitrogen on the (110) plane of tungsten were determined by thermal desorption and work function measurements. The low temperature γ-N2 state desorbs with first order kinetics and an activation energy of 6 kcal mole?1. The absence of isotope mixing between 14N2 and 15N2 demonstrates γ-N2 is adsorbed molecularly. Monolayer coverage shows a decrease of 0.19 eV in work function. A Topping model plot indicates the layer is immobile at 123 K. 相似文献
99.
100.
Gidal G Boyer J Butler F Cords D Abrams GS Amidei D Baden AR Barklow T Boyarski AM Burchat P Burke DL Dorfan JM Feldman GJ Gladney L Gold MS Goldhaber G Golding LJ Haggerty J Hanson G Hayes K Herrup D Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Karlen D Klein SR Lankford AJ Larsen RR LeClaire BW Levi ME Lockyer NS Lüth V Matteuzzi C Nelson ME Ong RA Perl ML Richter B Riles K Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH de la Vaissière C Wood DR Yelton JM Zaiser C 《Physical review letters》1987,59(18):2016-2019