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81.
In this paper we investigate a number of analytical solutions to the polynomial class of nonlinear Klein-Gordon equations in multidimensional spacetime. This is done in the context of classical 4 and 6 field theory, the former with and without the inclusion of an external force field conjugate to . Both massive (m0) and massless (m=0) cases are considered, as well as tachyonic solutions allowed (v>c). We first present a complete set of translationally invariant solutions for the 4 model and demonstrate the role of external force fields in altering the form of these solutions. Next, spherically symmetric solutions are discussed in both 4 and 6 cases since they provide the most realistic models of elementary particles. 相似文献
82.
Marian ?enkiewicz Marta Rauchfleisz Julian Polański W?odzimierz Engelgard 《Applied Surface Science》2007,253(22):8992-8999
The aim of this article was to show the effects of an electron radiation dose and presence of a compatibilizer on the oxidation of composites made of blends of low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene (PP), polystyrene (PS), and poly(ethylene terephthalate) (PET) as well as of blends of LDPE, HDPE, and PP. As the compatibilizers, the styrene-ethylene/butylene-styrene elastomer grafted with maleic anhydride (SEBS-g-MA) and trimethylol propane trimethylacrylate (TMPTA) were used; they were added in the amounts of 5, 10, and 15 wt% and 1, 2, and 3 wt%, respectively. The oxidation of the surface layer (SL) was investigated by the X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). It was found that the extent of the composite oxidation increased with the increasing dose of the electron radiation. The addition of the compatibilizers enhanced the oxidation of the SL but hindered the oxidation of the bulk of the material. 相似文献
83.
Aleksander A. Kubicki Piotr Bojarski Marek Grinberg Micha? Sadownik Benedykt Kukliński 《Optics Communications》2006,263(2):275-280
Apparatus to study time-evolution of emission spectra over very wide time and spectral range is described. Excitation part of the equipment consists of solid state Nd:YAG laser and optical parametric generator. The heart of the detection system consists of spectrograph and streak camera. The significance of optics and electronics built in the system for proper, fast and convenient measurements is underlined. The results of donor-acceptor energy transfer in a rigid polyvinyl alcohol matrix serve here as an example of application our equipment to study complex systems. 相似文献
84.
Jelena Cveticanin Aleksandra Krkljes Zorica Kacarevic-Popovic Miodrag Mitric Zlatko Rakocevic Djordje Trpkov Olivera Neskovic 《Applied Surface Science》2010,256(23):7048-94
In this paper, an advanced method of one-step functionalization of single and multi walled carbon nanotubes (SWCNTs and MWCNTs) using γ-irradiation was described. Two synthesis procedures, related with different reduction species, were employed. For the first time, poly(vinyl alcohol) PVA is successfully utilized as a source to reduce silver (Ag) metal ions without having any additional reducing agents to obtain Ag nanoparticles on CNTs. The decoration of carbon nanotubes with Ag nanoparticles takes place through anchoring of (PVA) on nanotube's surface. Optical properties of as-prepared samples and mechanism responsible for the functionalization of carbon nanotubes were investigated using UV-vis and FTIR spectroscopy, respectively. Decorated carbon nanotubes were visualized using microscopic techniques: transmission electron microscopy and scanning tunneling microscopy. Also, the presence of Ag on the nanotubes was confirmed using energy dispersive X-ray spectroscopy. This simple and effective method of making a carbon nanotube type of composites is of interest not only for an application in various areas of technology and biology, but for investigation of the potential of radiation technology for nanoengineering of materials. 相似文献
85.
The significance of the electron–phonon interaction for optically stimulated luminescence (OSL) process in quartz is demonstrated. OSL variation with temperature has been investigated for four samples of natural quartz. Changes of the OSL decay rate have been observed for all components of the OSL signal. The scale and tendency of these changes are comparable with outcomes of computer simulations carried out for the model composed of two deep electron traps, one shallow trap and one recombination centre, taking into account the electron–phonon interactions. 相似文献
86.
Dagmara I. Strumińska-Parulska 《Isotopes in environmental and health studies》2017,53(2):111-115
The idea behind this study was to investigate the most popular magnesium dietary supplements as a potential additional source of 210Pb in the human diet. The paper presents the results of 210Pb activities determined in different magnesium supplements, as well as an estimation of the annual effective radiation doses from 210Pb decay. The results showed that the highest value of 210Pb activity was found in a magnesium supplement of natural origin (dolomite) with a value of 2.97?±?0.18 mBq g–1. The highest annual radiation dose from 210Pb obtained from the magnesium daily recommended value (0.4 g of pure Mg) was calculated for dolomite tablets as 3.71?±?0.02 µSv·year–1. 相似文献
87.
Z. Świerczyński 《Journal of Nonlinear Mathematical Physics》2017,24(1):20-28
New periodic solutions of signum-Gordon equation are presented. We first find solutions φ0(x, t) defined for (x, t) ∈ ? × [0, T ] and satisfying the condition φ0(x, 0) = φ0(x, T ) = 0. Then these solutions are extended to the whole spacetime by using (2.4). 相似文献
88.
Blagovest Bahnev Mark D. Bowden Agnieszka Stypczyńska Sylwia Ptasińska Nigel J. Mason Nicholas St.J. Braithwaite 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2014,68(6):1-5
The coupled-channel optical method (CCOM) is implemented in this work to study the scattering of electron on rubidium atom at 20 eV. In order to provide a realistic calculation, the continuum effect of the scattering system is accounted by incorporate an ab initio optical potential into the CCOM calculation. The differential cross sections (DCS), as well as the reduced Stokes parameters of 5p excitation are reported and compared to the available experimental and theoretical data. 相似文献
89.
Z. M. Stepień 《Czechoslovak Journal of Physics》1993,43(9-10):1029-1033
The initial stages of oxide formation on Mo field emitter tips have been examined with the field emission microscopy and field electron spectroscopy. The oxide formed in situ on Mo tips by thermal treatment in pure oxygen atmosphere was found to be non-uniform with little evidence for coherent structure. The electron spectroscopy results are discussed in terms of the hypothesis that the emission process is a hot-electron emission. 相似文献
90.
J. Młyńczak K. Kopczyński Z. Mierczyk M. Malinowska P. Osiwiański 《Opto-Electronics Review》2012,20(1):87-90
The paper describes investigation of pulse laser generation in newly developed EAT14 glasses with the use of MALO saturable absorber. Different initial transmission of the saturable absorbers and different transmission of the output coupler were investigated. The laser generation was carried out using 976-nm pump wavelength. Comparison of peak powers, slop efficiencies and thresholds was made with a view to choose the best set of glass and saturable absorber for “eye-safe” microchip laser range-finder. The generated wavelengths by each sample were measured. 相似文献