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Hale KJ Frigerio M Manaviazar S Hummersone MG Fillingham IJ Barsukov IG Damblon CF Gescher A Roberts GC 《Organic letters》2003,5(4):499-502
[structure: see text] The synthesis of two truncated bryostatin analogues 2 and 3 is described. High-field NMR measurements on the C-ring analogue 3 in C(2)H(3)CN containing 25% (2)H(2)O have shown that it binds to the CRD2 of human PKC-alpha at virtually the same position as phorbol-13-acetate (PA) and bryostatin 1 (1). NMR titration studies have also revealed that 3 binds to the CRD2 with a potency similar in magnitude to PA but much less potently than 1. 相似文献
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Bhattacharya M Goodman CD Raghavan RS Palarczyk M Garcia A Rapaport J van Heerden IJ Zupranski P 《Physical review letters》2000,85(21):4446-4449
We report a 0 degrees 176Yb(p,n)176Lu measurement at IUCF where we used 120 and 160 MeV protons and the energy dependence method to determine Gamow-Teller (GT) matrix elements relative to the model independent Fermi matrix element. The data show that there is an isolated concentration of GT strength in the low-lying 1(+) states making the proposed Low Energy Neutrino Spectroscopy detector (based on neutrino captures on 176Yb) sensitive to pp and 7Be neutrinos and a promising detector to resolve the solar neutrino problem. 相似文献
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We consider diffraction by a semi-infinite crack located alonga fusion interface between two differing elastic media. Twotypes of crack, namely open and partially closed cracks, areinvestigated. An open crack is modelled by a stress-free contactboundary condition and a partially closed crack is modelledby a spring contact boundary condition. For the latter, thejump in the stress across the crack is assumed to be proportionalto the jump in the displacement across the crack. This situationarises in, for example, a K-weld where the fine grain of theparent material (for example, ferritic or forged austeniticsteel) is in stark contrast with the coarse-grained weld metal(for example, austenitic weld metal). In the metal weld thedirection of the grain axis varies through the metal. However,diffraction is a local phenomenon and so the austenitic steelis assumed to have a zonal axis so that it may be modelled bya transversely isotropic composite. The ferritic or forged austeniticsteel will be modelled as an isotropic material. 相似文献
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The calculated rate of events in some of the existing solar neutrino detectors is directly proportional to the rate of the
7Be(p, γ)8B reaction measured in the laboratory at low energies. However, the low-energy cross sections of this reaction are quite uncertain
as various measurements differ from each other by 30–40%. The Coulomb dissociation process which reverses the radiative capture
by the dissociation of 8B in the Coulomb field of a target, provides an alternate way of accessing this reaction. While this method has several advantages
(like large breakup cross sections and flexibility in the kinematics), the difficulties arise from the possible interference
by the nuclear interactions, uncertainties in the contributions of the various multipoles and the higher order effects, which
should be considered carefully. We review the progress made so far in the experimental measurements and theoretical analysis
of the breakup of 8B and discuss the current status of the low-energy cross sections (or the astrophysical S-factor) of the 7Be(p, γ)8B reaction extracted therefrom. The future directions of the experimental and theoretical investigations are also suggested.
Work supported by EPSRC, UK, grant nos J/95867 and L/94574. 相似文献
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IJ. Kim I. W. Choi S. K. Lee K. A. Janulewicz J. H. Sung T. J. Yu H. T. Kim H. Yun T. M. Jeong J. Lee 《Applied physics. B, Lasers and optics》2011,104(1):81-86
An ultrahigh contrast laser pulse of over 1011 for 6 ps before the main pulse was achieved by employing a double plasma mirror installed at the end of a 100 TW Ti:sapphire
laser system. Spatial beam qualities such as focusability and stability were found to be extremely sensitive in the range
of 14–360 J/cm2 on the double plasma mirror, while ultrahigh contrast was maintained. At the fluence of 90 J/cm2 the focusability of the ultrahigh contrast laser was not degraded, and the stability was very close to that obtained without
the double plasma mirror when the 2-dimensional normalized standard deviation and the correlation function for several laser
beam profiles were analyzed. These results are requisites for carrying out relativistic laser-plasma interactions with ultrahigh
contrast laser pulses, enabling the use of ultrathin solid targets. 相似文献
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