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151.
152.
153.
Wijnands F. Pendry J. B. Garcia-Vidal F. J. Bell P. M. Roberts P. J. Moreno L. Marti´n 《Optical and Quantum Electronics》1997,29(2):199-216
We present a new formalism for calculating the Green's function for Maxwell's equations. As our aim is to apply our formalism
to light scattering at surfaces of arbitrary materials, we derive the Green's function in a surface representation. The only
requirement on the material is that it should have periodicity parallel to the surface. We calculate this Green's function
for light of a specific frequency and a specific incident direction and distance with respect to the surface. The material
properties entering the Green's function are the reflection coefficients for plane waves at the surface. Using the close relationship
between the Green's function and the density of states (DOS), we apply our method to calculate the spontaneous emission rate
as a function of the distance to a material surface. The spontaneous emission rate can be calculated using Fermi's Golden
Rule, which can be expressed in terms of the DOS of the optical modes available to the emitted photon. We present calculations
for a finite slab of cylindrical rods, embedded in air on a square lattice. It is shown that the enhancement or suppression
of spontaneous emission strongly depends on the frequency of the light.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
154.
Steven R. Bell 《Advances in Mathematics》2002,172(1):15-52
We show that the classical kernel and domain functions associated to an n-connected domain in the plane are all given by rational combinations of three or fewer holomorphic functions of one complex variable. We characterize those domains for which the classical functions are given by rational combinations of only two or fewer functions of one complex variable. Such domains turn out to have the property that their classical domain functions all extend to be meromorphic functions on a compact Riemann surface, and this condition will be shown to be equivalent to the condition that an Ahlfors map and its derivative are algebraically dependent. We also show how many of these results can be generalized to finite Riemann surfaces. 相似文献
155.
J. Musil D. Hovorka M. Mišina A. J. Bell V. Studnička 《Czechoslovak Journal of Physics》1998,48(8):963-971
We investigated the structure and composition of titanium carbide thin films deposited by the reactive magnetron sputter ion
plating process as a function of deposition parameters. The films were sputtered onto unheated glass substrates by means of
an unbalanced planar d.c. magnetron equipped with a titanium target using a mixture of argon and methane. The deposition parameters
ranged from 0.05 Pa to 2 Pa for total working gas pressurep
T, from 10% to 60% (volume) for relative methane concentration in the working gas mixture, from 45 mm to 85 mm for the substrate-to-target
distanced
s-t and from −50V to −800V for the substrate biasU
S. It was found that the crystallinity of the thin films strongly decreases with increasingp
T,d
s-t andU
S. The experiments described show the conditions necessary to obtain sputter-deposited nanocrystalline titanium carbide films.
This work has been partially supported by the Grant Agency of the Czech Republic under Grant No. 106/96/K245 and by the Ministry
of Education of the Czech Republic under Grant No. VS96 059. 相似文献
156.
Thomas W. Bell Albert Firestone Frieda Guzzo Lain-Yen Hu 《Journal of inclusion phenomena and macrocyclic chemistry》1987,5(2):149-152
A series of macrocyclic ligands related to hexaaza[18]-annulene form stable complexes with alkali metal and alkaline earth ions. A planar, substituent-solubilized torand, consisting of multiply fused pyridine rings, has been synthesized and has been found to sequester calcium from a dilute source. 相似文献
157.
A. K. Aziz J. B. Bell M. Schneider R. P. Gilbert 《Mathematical Methods in the Applied Sciences》1982,4(1):307-316
A boundary value problem is considered for an equation of mixed type in a rectangle. An energy method is used to prove uniqueness for appropriate boundary conditions. Similar considerations for the adjoint problem allow one to prove the existence of a generalized solution to the problem. It is also shown that the energy method leads naturally to a finite element method. The method is described for a special case and convergence is shown for the resulting numerical procedure. 相似文献
158.
Peter C. Bell 《The Journal of the Operational Research Society》1985,36(11):975-982
The visual interactive model is now a part of the toolbag of the operational research professional, and new applications are being reported regularly. This paper reviews the state of the practice of visual interactive modelling and attempts to identify successful application areas and opportunities for future developments. 相似文献
159.
160.
W. Bell K. Braune G. Claesson D. Drijard M.A. Faessler H.G. Fischer H. Frehse R.W. Frey S. Garpman W. Geist P.C. Gugelot P. Hanke M. Heiden P.G. Innocenti T.J. Ketel E.E. Kluge G. Mornacchi Th. Walcher 《Physics letters. [Part B]》1982,112(3):271-276
The inclusive production of charged hadrons has been measured in αα and αp collisions at nucleon-nucleon c.m. energies (√snn)of 31 and 44 GeV, respectively, for transverse momenta pT up to 5 GeV/c in the central rapidity (y) region. at high pT the yields are consistent with being 4 times and 16 times highere than the ones in pp interactions at y=0, for αp and αα interactions, respectively. However, an enhancement over these factors, as expected from an earlier FNAL experiment, cannot be ruled out. 相似文献