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61.
K. -H. Brenner 《Applied physics. B, Lasers and optics》1988,46(2):111-120
The motivation for a digital optical computer is based on the shortcomings inherent in of electronic computers. Optics has solutions to offer especially in interconnects. Devices based on nonlinear optical effects are still in the early stages of their development. Hence at an intermediate stage hybrid opto-electronic computers might emerge. Their architectures should make use of the special attributes of optics. A specific approach called symbolic substitution logic is outlined. 相似文献
62.
High power lasers are useful instrument in producing hard and wear resistant surfaces on steel. It is shown that the mechanical behaviour of such surfaces is controlled by their residual stress state and their ductility which both can be varied considerably by changing the laser treatment parameters. 相似文献
63.
64.
Donald J. Nelson Anthony D. Theoharides Andra C. Nieburgs Richard K. Murray Federico Gonzalez-Fernandez Daeg S. Brenner 《International journal of quantum chemistry》1979,16(1):159-174
High resolution natural abundance carbon-13 NMR has been used previously to examine molecular motions and conformational transitions in the muscle calcium binding parvalbumins isolated from mirror carp. [S. J. Opella, D. J. Nelson, and O. Jardetzky, J. Chem. Phys. 64 , 2533 (1976) and D. J. Nelson, S. J. Opella, and O. Jardetzky, Biochemistry 15 , 5552 (1976).] The carbon-13 NMR spectrum of parvalbumin typically reveals the presence of a number of well-resolved resonances from single-carbon sites in the protein. Since accurate assignment of these resonances to specific carbon atoms in the protein is essential before these resonances can be employed as probes of local conformational events, an investigation of the origin of a number of single-carbon resonances has been performed. Carbon-13 NMR on Tb(III)- and Yb(III)-substituted parvalbumin is the principal spectroscopic technique employed; however, results from terbium fluorescence spectroscopy, γ-ray scintillation spectroscopy, and x-ray difference Fourier analysis all contribute to single-carbon site assignment. The principal conclusions drawn from the combined spectroscopic results are that: (1) the downfield carboxyl resonance at 184.6 ppm, previously attributed to Glu-81, whose carboxyl group is involved in an internal ionic bond, originates rather from a carboxyl function coordinating the solvent exposed metal ion, (2) the carbonyl resonance at 168.9 ppm arises from Lys-96, as was previously suggested; and (3) the 11.2 ppm resonance derives from the δ-methyl carbon of Ile-97, a resonance assignment that could not be made previously. 相似文献
65.
Global classical solutions of nonlinear wave equations 总被引:2,自引:0,他引:2
66.
Summary Without using spectral resolution, an elementary proof of convergence of Seidel iteration. The proof is based on the lemma (generalizing a lemma of P. Stein): If (A+A
*)–B
*(A+A
*)B>0, whereB=–(P+L)
–1
R,A=P+L (Lower)+R (upper), then Seidel iteration ofAX=Y
0 converges if and only ifA+A
*>0. This lemma has as corollaries not only the well-known results of E. Reich and Stein, but also applications to a matrix that can be far from symmetric, e.g.M=[A
ij
]
1
2
, whereA
21=–A
12
*
,A
11,A
22 are invertible;A
11
+A
11
*
=A22+A
22
*
; and the proper values ofA
12
–1
A
11,A
12
*–1
A
22 are in the interior of the unit disk.Supported under NSF GP 32527.Supported under NSF GP 8758. 相似文献
67.
68.
69.
70.
W. Klamra K. Fransson B. Sundström M. Brenner S. Engman R. KvarnströM 《Nuclear Physics A》1982,376(3):463-477
The energy level structure of 101Ru was studied using the reactions 100Mo(α, 3n)101Ru and 100Mo(3He, 2n)101Ru. Excitation functions, γγ coincidences and γ-ray angular distributions were measured. Three ΔI = 2 cascades proceeding to a , and state were observed. A decay scheme is presented showing energies up to 5849 keV and spins up to . The bands are discussed within the framework of the Nilsson model with Coriolis coupling in which the recoil effect has been properly introduced. 相似文献