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1.
Marcin Drag Jolanta Grembecka Paweł Kafarski 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1591-1595
The design, stereo-, and enantioselective synthesis and activity prediction of aminophosphonic acids as new leucine aminopeptidase inhibitors will be discussed. 相似文献
2.
Herein we report a facile synthesis of esters of bis‐α‐aminoalkylphosphinic acids obtained by an addition of Cbz‐protected phosphinic analogues of amino acid methyl esters to an appropriate imine in refluxing benzene. Complete deprotection of the esters could be achieved in one step by the action of 30% HBr in acetic acid. 相似文献
3.
Melkonian JM Forget N Bretenaker F Drag C Lefebvre M Rosencher E 《Optics letters》2007,32(12):1701-1703
We report on what we believe to be the first active mode locking of near-degenerate, doubly and singly resonant cw-pumped optical parametric oscillators (OPOs). We show experimentally that a steady-state regime of short pulses is reached in a few tens of microseconds under cw pumping. The oscillation buildup dynamics of both OPOs is also explored, evidencing an unusual transient behavior in the mode-locking process. 相似文献
4.
Drag C Laburthe Tolra B T'Jampens B Comparat D Allegrini M Crubellier A Pillet P 《Physical review letters》2000,85(7):1408-1411
In photoassociation spectroscopy, the line intensities of a given vibrational progression exhibit zero-signal modulation reflecting the node structure of the s-wave ground state wave function of two free colliding atoms. This leads to the determination of the scattering length. We performed photoassociation of cold Cs atoms polarized in the Zeeman sublevel f = 4, m(f) = 4. We analyzed the intensities of the lines associated with the Cs2 0(-)(g) state dissociating to the 6s(1/2)+6p(3/2) asymptote. This yields a value of the Cs triplet state scattering length, a(T) = -530a(0), while consistency requirements impose a value of the multipole ground state molecular coefficient, C6 = 6510 a.u. 相似文献
5.
Changes of the radioactive decay rate of71Ge (T 1/2=11.43 days) have been studied experimentally for71Ge in some compounds of bivalent and quadrivalent germanium. Relative changes Δλ/λ of the electron capture probability have been measured, and the chemical changes Δρ(0) of the electron density at the germanium nuclei have been determined from these measurements. Values for the Mössbauer isomer shift calibration constants for the 67 keV γ-transition of73Ge have been estimated:C=δ/Δρ(0)=(0.061±0.020) mm·s?1/a.u., Δ〈r 2〉=(21±7)·10?3 fm2, ΔR/R=(6.9±2.3)·10?4. 相似文献
6.
V. Remeikis K. Makariūnas A. Dragūnas R. Davidonis R.L. Kalinauskas 《Hyperfine Interactions》2000,128(4):397-408
The γ‐spectrometry method for determination of the relative change ΔλEC/λEC in the partial probability λEC for the 114mIn decay branch by the electron capture (EC), when the nucleus is in different chemical environments, was developed. The method
is based on an experimental determination of the relative change ΔIγ/Iγ in the intensity of the γ‐radiation which is emitted by the excited daughter 114Cd nuclei after EC. The 114mIn decay by EC in indium metal, In2O3 and InAs was compared. The largest ΔIγ/Iγ=(2.5±0.8)·10−4 has been found for InAs relatively to In2O3. The chemical changes in the electron density on the indium nucleus corresponding to the measured ΔIγ/Iγ values have been determined.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
The gross structure oscillations recently observed in heavy-ion elastic or inelastic scattering and fusion cross sections are here analyzed in terms of nuclear surface (creep) wave resonances. Their dispersion curves characterize these waves as being of Rayleigh or of Whispering-Gallery type. 相似文献
8.
A. Fioretti D. Comparat C. Drag C. Amiot O. Dulieu F. Masnou-Seeuws P. Pillet 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1999,5(3):389-403
The photoassociative spectroscopy of the Cs2 0 g - long-range molecular state dissociating into the asymptote is performed, using cold cesium atoms in a vapor-cell magneto-optical trap (MOT). Vibrational levels from v =0 to v =132 are identified, and their rotational structure is well resolved up J =8 for levels below v =74. These data are analyzed in terms of the Rydberg-Klein-Rees (RKR) procedure, and correspond to 99.6% of an effective potential curve with a minimum at ? and a cm-1 depth. Both ab initio calculations and simple model estimations predict a double-well structure for this potential curve, which cannot be reproduced presently by the RKR approach but which is confirmed by the presence of giant structures in the spectrum. The 1u()long-range state is also observed for the first time in Cs2. 相似文献
9.
Dragässer A Shekhah O Zybaylo O Shen C Buck M Wöll C Schlettwein D 《Chemical communications (Cambridge, England)》2012,48(5):663-665
A layer of a metal-organic framework (SURMOF) was prepared on a thiol monolayer on Au. Charge transport across the insulating membrane could be established by using ferrocene as an immobilised redox mediator. Reversibility of the immobilisation and its role in the electrode kinetics are discussed. 相似文献
10.
C. Drag I. Ribet M. Jeandron M. Lefebvre E. Rosencher 《Applied physics. B, Lasers and optics》2001,73(3):195-200
The temporal behavior of a nanosecond pulsed singly resonant periodically poled lithium niobate optical parametric oscillator
has been studied both theoretically and experimentally. Taking into account the cylindrical symmetry of the system, a numerical
model based on the Hankel transform has been developed. Good agreement is obtained between experiment and simulation. Moreover,
the computation time is reduced roughly by a factor of 60 compared to the usual simulation software.
Received: 23 April 2001 / Published online: 19 September 2001 相似文献