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51.
A family of nonlinear conservative finite difference schemes for the multidimensional Boussinesq Paradigm Equation is considered.
A second order of convergence and a preservation of the discrete energy for this approach are proved. Existence and boundedness
of the discrete solution on an appropriate time interval are established. The schemes have been numerically tested on the
models of the propagation of a soliton and the interaction of two solitons. The numerical experiments demonstrate that the
proposed family of schemes is about two times more accurate than the family of schemes studied in [Kolkovska N., Two families
of finite difference schemes for multidimensional Boussinesq paradigm equation, In: Application of Mathematics in Technical
and Natural Sciences, Sozopol, June 21–26, 2010, AIP Conf. Proc., 1301, American Institute of Physics, Melville, 2010, 395–403]. 相似文献
52.
M. N. Achasov K. I. Beloborodov A. V. Berdyugin A. G. Bogdanchikov D. A. Bukin A. V. Vasiljev V. B. Golubev T. V. Dimova V. P. Druzhinin L. V. Kardapoltsev I. A. Koop A. A. Korol S. V. Koshuba E. V. Pakhtusova S. I. Serednyakov Z. K. Silagadze A. N. Skrinsky A. G. Kharlamov Yu. M. Shatunov 《Journal of Experimental and Theoretical Physics》2011,113(1):75-79
In the energy range from 1.05 to 1.38 GeV, the upper limits for the cross sections of e + e ? → f 0(600)γ, f 0(980)γ, f 0(1350)γ, and f 2(1270)γ → π0π0γ processes have been established. Measurements are performed in accordance with the statistics gathered in experiment with a spherical neutral detector (SND) on the VEPP-2M e + e ? collider. The resultant upper limits vary from 6 to 42 pb depending on the energy and the model. 相似文献
53.
M. N. Achasov K. I. Beloborodov A. V. Berdyugin A. G. Bogdanchikov A. D. Bukin D. A. Bukin A. V. Vasil’ev V. B. Golubev T. V. Dimova V. P. Druzhinin I. A. Koop A. A. Korol’ S. V. Koshuba E. V. Pakhtusova E. A. Perevedentsev S. I. Serednyakov Z. K. Silagadze A. N. Skrinsky Yu. M. Shatunov 《Journal of Experimental and Theoretical Physics》2008,107(1):61-68
The e + e ? → ω, ρ → π0 e + e ? processes have been investigated in the experiments with Spherical Neutral Detector at the VEPP-2M e + e ? collider. The measurements provide the probability ?(ω → π0 e + e ?) = (0.761 ± 0.053 ± 0.064) × 10?3 of the ω → π0 e + e g- conversion decay and the upper limit ?(ρ → π0 e + e ?) < 1.2 × 10?5 (at 90% CL) for the ρ → π0 e + e ? decay. The transition form factor was measured at three values of the 4-momentum transfer squared. 相似文献
54.
M. N. Achasov K. I. Beloborodov A. V. Berdyugin A. G. Bogdanchikov A. V. Bozhenok A. D. Bukin D. A. Bukin S. V. Burdin A. V. Vasil’ev D. I. Ganyushin V. B. Golubev T. V. Dimova A. A. Drozdetskii V. P. Druzhinin P. M. Ivanov V. N. Ivanchenko A. A. Korol’ M. S. Korostelev S. V. Koshuba G. A. Kukartsev E. V. Pakhtusova A. A. Polunin E. É. Pyata A. A. Sal’nikov S. I. Serednyakov V. A. Sidorov Z. K. Silagadze V. V. Sharyi Yu. M. Shatunov 《JETP Letters》2000,71(9):355-358
The e + e ?→π0π0 γreaction was studied in the energy range 0.36–0.97 GeV on a VEPP-2M e + e ? collider with an SND detector. The decay probabilities were found to be B(ω→ π0π0γ)= (7.8 ±2.7±2.0)×10?5 and B(π→ π0π0γ)= (4.8 ?1.8 +3.4 ±0.2)×10?5. 相似文献
55.
E. Dimova O. Morizot G. Stern C. L. Garrido Alzar A. Fioretti V. Lorent D. Comparat H. Perrin P. Pillet 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,42(2):299-308
We have demonstrated and modeled a simple and efficient method to transfer atoms from a first Magneto-Optical Trap (MOT) to
a second one. Two independent setups, with cesium and rubidium atoms respectively, have shown that a high power and slightly
diverging laser beam optimizes the transfer between the two traps when its frequency is red-detuned from the atomic transition.
This pushing laser extracts a continuous beam of slow and cold atoms out of the first MOT and also provides a guiding to the
second one through the dipolar force. In order to optimize the transfer efficiency, the dependence of the atomic flux on the
pushing laser parameters (power, detuning, divergence and waist) is investigated. The atomic flux is found to be proportional
to the first MOT loading rate. Experimentally, the transfer efficiency reaches 70%, corresponding to a transfer rate up to
2.7×108 atoms/s with a final velocity of 5.5 m/s. We present a simple analysis of the atomic motion inside the pushing–guiding laser,
in good agreement with the experimental data. 相似文献
56.
The systems Cd(C6H5COO)2 CdCl2 H2O and Cd(C6H5COO) 2 CdBr2 H2O have been studied at 25 °C. Formation of the double salts Cd(C6H5COO)2 · CdCl2 and Cd(C6H5COO)2 · CdBr2(1:1:0) has been established and their chemical individuality has been confirmed by chemical, X-ray, and DT-analyses. Proceeding from data on the structure of Cd(C6H5COO)2 · 2 H2O and the composition of the 1:1:0 double salts as well as using Pauling's rules for the most probable spacial disposition of the ions, the crystal structure type of the double salts obtained are predicted. 相似文献
57.
Boron carbon nitride nanostructures from salt melts: tunable water-soluble phosphors 总被引:1,自引:0,他引:1
Lei W Portehault D Dimova R Antonietti M 《Journal of the American Chemical Society》2011,133(18):7121-7127
A simple, high yield, chemical process is developed to fabricate layered h-BN nanosheets and BCNO nanoparticles with a diameter of ca. 5 nm at 700 °C. The use of the eutectic LiCl/KCl salt melt medium enhances the kinetics of the reaction between sodium borohydride and urea or guanidine as well as the dispersion of the nanoparticles in water. The carbon content can be tuned from 0 to 50 mol % by adjusting the reactant ratio, thus providing precise control of the light emission of the particles in the range 440-528 nm while reaching a quantum yield of 26%. Because of their green synthesis, low toxicity, small size, and stability against aggregation in water, the as-obtained photoluminescent BCNO nanoparticles show promise for diagnostics and optoelectronics. 相似文献
58.
Clara Silvestre Sossio Cimmino Maria Raimo Cosimo Carfagna Vincenzo Capuano Rumiana Kotsilkova 《Macromolecular Symposia》2005,228(1):99-114
The effect of the addition of two combined fillers, smectite clay and diamond and smectite clay and carbon nanoparticles, on structure, morphology, isothermal and non isothermal crystallization behaviour, tensile and thermal properties of isotactic polypropylene (iPP) has been investigated by using several techniques: wide angle X-ray diffraction, optical and scanning electron microscopy, thermogravimetry, differential scanning calorimetry and tensile techniques. It was found that nanoparticles of diamond and carbon favour the nucleation of the β-form of iPP crystal, whereas the clay nanolayers do not have any influence on the crystal structure of iPP. The thermal stability of iPP/(clay+diamond) and iPP/(clay+carbon) is improved with respect to neat iPP, whereas no influence is detected when only clay is added to iPP. At the given crystallization conditions, the overall crystallization peak of iPP/(clay+diamond) almost exactly overlaps the crystallization peak of neat iPP, whereas in the case of iPP/clay and iPP/(clay+carbon) the maximum of the crystallization peaks is shifted to higher temperature. The spherulite growth rate, G values do not differ from one another. The iPP/(clay+carbon) system shows ductile behavior. The other systems show brittle behavior with failure before necking. These results were related with the very high percentage of beta phase present in the samples of iPP/(clay+carbon). 相似文献
59.
M.N. Achasov A.V. Berdyugin A.V. Bozhenok D.A. Bukin S.V. Burdin T.V. Dimova V.P. Druzhinin M.S. Dubrovin I.A. Gaponenko V.B. Golubev V.N. Ivanchenko A.A. Korol S.V. Koshuba E.V. Pakhtusova A.A. Salnikov S.I. Serednyakov V.V. Shary Yu.M. Shatunov V.A. Sidorov Z.K. Silagadze 《The European Physical Journal C - Particles and Fields》2000,12(1):25-33
60.
M.N. Achasov S.E. Baru A.V. Bozhenok A.D. Bukin D.A. Bukin S.V. Burdin T.V. Dimova S.I. Dolinsky V.P. Druzhinin M.S. Dubrovin I.A. Gaponenko V.B. Golubev V.N. Ivanchenko A.A. Korol S.V. Koshuba A.P. Lysenko I.N. Nesterenko E.V. Pakhtusova S.I. Serednyakov V.V. Shary Yu.M. Shatunov V.A. Sidorov Z.K. Silagadze Yu.V. Usov 《The European Physical Journal C - Particles and Fields》2000,12(3):369-374