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排序方式: 共有271条查询结果,搜索用时 843 毫秒
31.
To interpret recent spin-, energy- and angle-resolved experimental photoemission spectra at photon energies ranging from 20 to 70 eV, one-step calculations on the basis of a non-relativistic Green function formalism have been performed together with a calculation of the corresponding bulk band structure and momentum-resolved layer-by-layer quasi-particle density of states. The theoretical spectra are in good agreement with the data. Individual features are explained in terms of bulk interband transitions and emission from a majority-spin surface resonance. Self-energy corrections are found to be important and in qualitative disagreement with recent microscopic theory. 相似文献
32.
Cirillo N.C. Fraasch A. Lee H. Eastman L.F. Shur M.S. Baier S. 《Electronics letters》1984,20(21):854-855
The fabrication of self-aligned gate by ion implantation modulation doped (Al,Ga)As/GaAs field effect transistors (MODFETs) utilising a novel multilayer structure capable of withstanding the high-temperature furnace anneals required for Si implant activation is reported. Typical measured extrinsic transconductances of 175 mS/mm at 300 K and 290 mS/mm at 77 K were achieved on 1.1 ?m-gate-length devices. Values of the two-dimensional electron gas saturation velocity of 1.9×107 cm/s at 300 K and 2.7×107 cm/s at 77 K were obtained from an analysis of the FET drain current/voltage characteristics using the charge-control model. 相似文献
33.
Othmar Baier 《Mathematische Zeitschrift》1959,71(1):94-98
Ohne ZusammenfassungHerrnRobert Sauer zum 60. Geburtstag gewidmet 相似文献
34.
Baumert M Baier V Truebner S Schirdewan A Voss A 《IEEE transactions on bio-medical engineering》2005,52(12):2112-2115
Autonomic cardiovascular control involves complex interactions of heart rate and blood pressure. In patients with dilated cardiomyopathy (DCM), this control is impaired and parameters for its quantification might be of prognostic importance. In this paper, we introduce methods based on joint symbolic dynamics (JSD) for the enhanced analysis of heart rate and blood pressure interactions. To assess the coarse-grained dynamics beat-to-beat changes of heart rate and blood pressure are encoded in symbol strings. Subsequently, the distribution properties of short symbol sequences (words) as well as the scaling properties of the whole symbol string are assessed. The comparison of joint symbolic heart rate and blood pressure dynamics in DCM (n = 75) with those in healthy controls (n = 75) showed significant changes. Both, the distribution of words and the scaling properties indicate a loss in heart rate dynamics associated with blood pressure regulation in DCM. In conclusion, the analyses of short- and long-term JSDs provide insights into complex physiological heart rate and blood pressure interactions and furthermore reveal patho-physiological cardiovascular control in DCM. 相似文献
35.
A set of separable potentials forNN, NΔ andΔΔ configuration transition potentials was fitted toNN phase shifts, the deuteron binding energy and the quadrupole moment. Our results agree quite well with more realistic calculations and will be especially useful for numerical investigations of Faddeev like relativistic few body problems. 相似文献
36.
L. Mollard G. Destefanis N. Baier J. Rothman P. Ballet J. P. Zanatta M. Tchagaspanian A. M. Papon G. Bourgeois J. P. Barnes C. Pautet P. Fougères 《Journal of Electronic Materials》2009,38(8):1805-1813
This paper reviews recent developments in the characterization of planar p-on-n photodiodes fabricated from long- and mid-wavelength Hg1−x
Cd
x
Te at␣the Electronics and Information Technology Laboratory (LETI). The Hg1−x
Cd
x
Te epitaxial layers were grown by both liquid-phase and molecular-beam epitaxy. Planar p-on-n photodiodes were fabricated by arsenic implantation into an indium-doped Hg1−x
Cd
x
Te base layer. Electro-optical characterization on these p-on-n photodiodes showed low leakage currents (shunt resistance > 10 GΩ) and mean R
0
A values comparable to the state of the art, i.e., equal to 5000 Ω cm2 at λ
c = 9.3 μm (λ
c: cutoff wavelength). Results of focal-plane arrays operating in both the long-wavelength infrared (IR) and middle-wavelength
IR bands are reported, with noise equivalent delta temperature and responsivity values at λ
c = 9.3 μm in excess of 99.64%. These results demonstrate the viability and technological maturity of both material growth and device
processing. 相似文献
37.
We investigate various mean value problems involving order 3 primitive Dirichlet characters. In particular, we obtain an asymptotic formula for the first moment of central values of the Dirichlet L-functions associated to this family, with a power saving in the error term. We also obtain a large sieve-type result for order 3 (and 6) Dirichlet characters. 相似文献
38.
Lepton-pair production from deep inelastic scatteringin peripheral relativistic heavy ion collisions
U. Dreyer T. Baier K. Hencken D. Trautmann 《The European Physical Journal C - Particles and Fields》2006,45(3):783-795
We calculate the inelastic electron- and muon-pair production in peripheral relativistic heavy ion collisions in the region
of large Q2 of one of the photons. This offers a possibility to study the quark distribution functions in ions in "ultraperipheral heavy
ion collisions". The calculations are compared with those making use of the equivalent photon and the equivalent lepton approximation.
We compare the results for Pb-Pb and Pb-p collisions at RHIC (γ ≈ 100) and LHC (γ ≈ 3000) energies. Furthermore we include nuclear modifications to the parton distribution
functions in our calculations to study their effect on the cross sections. 相似文献
39.
Mischa Baier Nils H. Rustmeier Joachim Harr Norbert Cyrus Guido J. Reiss Andrea Grafmüller Brbel S. Blaum Thilo Stehle Laura Hartmann 《Macromolecular bioscience》2019,19(5)
Divalent precision glycooligomers terminating in N‐acetylneuraminic acid (Neu5Ac) or 3′‐sialyllactose (3′‐SL) with varying linkers between scaffold and the glycan portions are synthesized via solid phase synthesis for co‐crystallization studies with the sialic acid‐binding major capsid protein VP1 of human Trichodysplasia spinulosa‐associated Polyomavirus. High‐resolution crystal structures of complexes demonstrate that the compounds bind to VP1 depending on the favorable combination of carbohydrate ligand and linker. It is found that artificial linkers can replace portions of natural carbohydrate linkers as long as they meet certain requirements such as size or flexibility to optimize contact area between ligand and receptor binding sites. The obtained results will influence the design of future high affinity ligands based on the structures presented here, and they can serve as a blueprint to develop multivalent glycooligomers as inhibitors of viral adhesion. 相似文献
40.
The spectral dynamics of individual bacterial light-harvesting-2 pigment-protein complexes have been studied at 1.4 K. The data provided the spectral diffusion kernel of the optical transitions of the embedded B800 bacteriochlorophyll a pigments. This kernel can be described by either a single Gaussian function or a superposition of Gaussian functions. Moreover, we found that the chromophores interact with two classes of TLSs that can be distinguished by their distance from the chromophore and are most likely located outside (class 1) and inside (class 2) the protein matrix. 相似文献