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991.
We investigate permeation energetics of water entering a model dimyristoylphosphatidylcholine (DMPC) bilayer via molecular dynamics simulations using polarizable Charge Equilibration (CHEQ) models. Potentials of mean force show 4.5-5.5 kcal/mol barriers for water permeation into bilayers. Barriers are highest when water coordination within the bilayer is prevented, and also when using force fields that accurately reproduce experimental alkane hydration free energies. The magnitude of the average water dipole moment decreases from 2.6 Debye (in bulk) to 1.88 Debye (in membrane interior). This variation correlates with the change in a water molecule's coordination number. 相似文献
992.
The nef cone volume appeared first in work of Peyre in a number-theoretic context on Fano varieties, and was then studied by Derenthal and co-authors in a series of papers on del Pezzo surfaces. The idea was subsequently extended to also measure the Zariski chambers of del Pezzo surfaces. We start in this paper to explore the possibility to use this attractive concept to effectively measure the size of the nef cone on algebraic surfaces in general. This provides an interesting way of measuring in how big a space an ample line bundle can be moved without destroying its positivity. We give here complete results for simple abelian surfaces that admit a principal polarization and for products of elliptic curves. 相似文献
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994.
M.F. Beaux T. Durakiewicz L. Moreschini M. Grioni F. Offi G. Monaco G. Panaccione J.J. Joyce E.D. Bauer J.L. Sarrao M.T. Butterfield E. Guziewicz 《Journal of Electron Spectroscopy and Related Phenomena》2011,184(8-10):517-524
Electronic structure of single crystal UPd3, UGe2, and USb2 has been measured from hard X-ray photoelectron spectroscopy (HAXPES) with 7.6 keV photons at the European Synchrotron Radiation Facility (ESRF). Lower photon energy angle-resolved photoelectron spectroscopy (ARPES) was also performed at the Synchrotron Radiation Center (SRC). Herein the following results are presented: (i) ARPES results demonstrate hybridization between the U 5f and Pd 4d electrons within UPd3. (ii) The greatly reduced surface sensitivity of HAXPES enabled observation of the bulk core levels in spite of surface oxidation. Photoelectron mean-free-path versus oxide layer thickness considerations were used to model the effectiveness of HAXPES for probing bulk features of in-air cleaved samples. (iii) Two distinct features separated by 800 meV were observed for the Sb 3d core level. These two features are attributed to manifestations of two distinct Sb sites within the USb2 single crystal as supported by consideration of interatomic distances and enthalpy-of-formation. (iv) Doniach–Sunjic line shape analysis of core level spectral features revealed correlations between asymmetry coefficients and 5f localization. 相似文献
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F. Sch?ttiger D. Bauer J. Demsar T. Dekorsy J. Kleinbauer D. H. Sutter J. Puustinen M. Guina 《Applied physics. B, Lasers and optics》2012,106(3):605-612
We report a comparative study of carrier dynamics in semiconductor saturable absorber mirrors (SESAMs) containing InGaAs quantum
wells and InGaAsN quantum wells (QWs). The static and dynamic reflectivity spectra were measured with a Fourier-transform-infrared-spectrometer
and a pump-probe setup, respectively. The influence of rapid thermal annealing (RTA) on carrier dynamics was studied. Due
to the reduction of defect states by RTA we observed an increase of the static reflectivity and an increase of the electron–hole
recombination time. 相似文献
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