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191.
I.R. Girling P.V. Kolinsky N.A. Cade J.D. Earls I.R. Peterson 《Optics Communications》1985,55(4):289-292
We report here the investigation of the second harmonic generation from a non-centrosymmetric alternating Langmuir-Blodgett film of ω-tricosenoic acid and highly polarisable merocyanine dye. Results for films containing one, two and three layers of the merocyanine dye are described. 相似文献
192.
Synchrotron radiation photoemission studies of Ca and CaH2 reveal changes in the electronic structure and bonding which directly reflect metal-hydrogen interactions. The results indicate similarities between the saline dihydrides and the transition metal dihydrides, particularly the energy location and width of the bonding band states. Combined with APW band calculations for CaH2 in the CaF2 structure, they provide new insight regarding bonding in hydrides. 相似文献
193.
The isoscalar transition rates and neutron-stripping probabilities to states of 14C have been measured using the 35 MeV 14C(α, α')14C and 17.7 MeV 13C(d, p)14C reactions. States showing great charge asymmetries in pion scattering at 8.32 MeV (2+) and 11.7 MeV (4?) were examined in detail. Isoscalar transition rates B(02) were determined to be 168, 96 and 74 fm4 for the 7.01, 8.32 and 10.45 MeV 2+ states, with identical single-neutron spectroscopic factors of 0.065, from the (d, p) data, for the lowest two states. 相似文献
194.
195.
In the current paper, we present a series of results on the asymptotic and spectral analysis of coupled Euler‐Bernoulli and Timoshenko beam model. The model is well‐known in the different branches of the engineering sciences, such as in mechanical and civil engineering (in modelling of responses of the suspended bridges to a strong wind), in aeronautical engineering (in predicting and suppressing flutter in aircraft wings, tails, and control surfaces), in engineering and practical aspects of the computer science (in suppressing bending‐torsional flutter of a new generation of hard disk drives, which is expected to pack high track densities (20,000+TPI) and rotate at very high speeds (25,000+RPM)), in medical science (in bio mechanical modelling of bloodcarrying vessels in the body, which are elastic and collapsible). The aforementioned mathematical model is governed by a system of two coupled differential equations and a two parameter family of boundary conditions representing the action of the self‐straining actuators. This linear hyperbolic system is equivalent to a single operator evolution equation in the energy space. That equation defines a semigroup of bounded operators and a dynamics generator of the semigroup is our main object of interest. We formulate and proof the following results: (a) the dynamics generator is a nonselfadjoint operator with compact resolvent from the class ??p with p > 1; (b) precise spectral asymptotics for the two‐branch discrete spectrum; (c) a nonselfadjoint operator, which is the inverse of the dynamics generator, is a finite‐rank perturbation of a selfadjoint operator. The latter fact is crucial for the proof that the root vectors of the dynamics generator form a complete and minimal set. In our forthcoming paper, we will use the spectral results to prove that the dynamics generator is Riesz spectral, which will allow us to solve several boundary and distributed controllability problems via the spectral decomposition method. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
196.
Morrison R Schmidt D Procario M Johnson DR Lingel K Rankin P Smith JG Alexander J Artuso M Bebek C Berkelman K Besson D Browder TE Cassel DG Cheu E Coffman DM Drell PS Ehrlich R Galik RS Garcia-Sciveres M Geiser B Gittelman B Gray SW Hartill DL Heltsley BK Honscheid K Kandaswamy J Katayama N Kreinick DL Lewis JD Ludwig GS Masui J Mevissen J Mistry NB Nandi S Ng CR Nordberg E O'Grady C Patterson JR Peterson D Pisharody M Riley D Sapper M Selen M Worden H Worris M Avery P Freyberger A Rodriguez J 《Physical review letters》1991,67(13):1696-1700
197.
Akerib DS Barish B Cowen DF Eigen G Stroynowski R Urheim J Weinstein AJ Morrison R Schmidt D Procario M Johnson DR Lingel K Rankin P Smith JG Alexander J Bebek C Berkelman K Besson D Browder TE Cassel DG Cheu E Coffman DM Drell PS Ehrlich R Galik RS Garcia-Sciveres M Geiser B Gittelman B Gray SW Hartill DL Heltsley BK Honscheid K Kandaswamy J Katayama N Kreinick DL Lewis JD Ludwig GS Masui J Mevissen J Mistry NB Nandi S Ng CR Nordberg E O'Grady C Patterson JR Peterson D Pisharody M Riley D 《Physical review letters》1991,67(13):1692-1695
198.
199.
Bosted PE Andivahis L Lung A Stuart LM Alster J Arnold RG Chang CC Dietrich FS Dodge W Gearhart R Gomez J Griffioen KA Hicks RS Hyde-Wright CE Keppel C Kuhn SE Lichtenstadt J Miskimen RA Peterson GA Petratos GG Rock SE Rokni S Sakumoto WK Spengos M Swartz K Szalata Z Tao LH 《Physical review letters》1992,68(26):3841-3844
200.
Daoudi M Ford WT Johnson DR Lingel K Lohner M Rankin P Smith JG Alexander J Bebek C Berkelman K Besson D Browder TE Cassel DG Cheu E Coffman DM Drell PS Ehrlich R Galik RS Garcia-Sciveres M Geiser B Gittelman B Gray SW Hartill DL Heltsley BK Honscheid K Kandaswamy J Katayama N Kim PC Kreinick DL Lewis JD Ludwig GS Masui J Mevissen J Mistry NB Nandi S Ng CR Nordberg E O'Grady C Patterson JR Peterson D Pisharody M Riley D Sapper M Selen M Worden H Worris M Avery P Freyberger A Rodriguez J 《Physical review D: Particles and fields》1992,45(11):3965-3975