Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "43.20.+g" wg kryterium: Temat


Wyświetlanie 1-5 z 5
Tytuł:
Phononic Band Gap Width Control through Structural and Material Parameters in Two-Dimensional Phononic Crystals
Autorzy:
Śliwa, I.
Krawczyk, M.
Powiązania:
https://bibliotekanauki.pl/articles/2044562.pdf
Data publikacji:
2005-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
43.20.+g
43.35.+d
43.40.+s
Opis:
The phononic band structures of two-dimensional solid phononic crystals with different lattice and scatterer symmetry are studied numerically, with three types of lattice (square, triangular, and rectangular) and four different scatterer shapes (circle, hexagon, square, and rectangle) considered. XY and Z vibration modes are investigated separately. Two types of phononic crystal are considered: one composed of high-density rods embedded in a low-density matrix, the other of low-density rods in a high-density matrix. In the former case, lattice type and polarization being fixed, the broadest gaps are obtained when the symmetry of the rods corresponds to that of the lattice (the shape of a rod is identical with that of the first Brillouin zone); the largest gap width values are observed in triangular lattice-based crystals (compared to those based on the square and rectangular lattices), the shape of the corresponding first Brillouin zone being closest to a circle. These rules do not apply to structures in which the density of the rod material is lower than that of the matrix. In this case, when the symmetry of the rods corresponds to that of the lattice, gaps either fail to appear at all, or are much narrower than in other configurations. The effect of other material parameter values (such as the longitudinal and transversal velocity values) on the relation between the energy gap width and the scatterer symmetry is found to be much lesser.
Źródło:
Acta Physica Polonica A; 2005, 108, 6; 943-957
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Acoustic Pressure Radiated by a Vibrating Circular Plate within the Fraunhofer Zone of the Three-Wall Corner Region
Autorzy:
Szemela, K.
Rdzanek, W.
Powiązania:
https://bibliotekanauki.pl/articles/1490263.pdf
Data publikacji:
2012-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
43.20.Ks
43.20.Rz
43.40.+s
43.20.-f
43.20.+g
Opis:
The Neumann boundary value problem has been solved for the region bounded by the three perfect rigid infinite baffles arranged perpendicularly to one another. The harmonically vibrating clamped circular plate embedded in one of the baffles is the sound source. It has been assumed that the amplitude of the plate's transverse vibrations is small to use the linear Kelvin-Voigt theory. The Green function has been applied to obtain the asymptotic formulae describing the distribution of the acoustic pressure within the Fraunhofer zone. The analysis of sound radiation has been performed for some selected surface excitations and for some different plate's locations. The acoustic pressure distribution has been examined including the acoustic attenuation and the internal attenuation of the plate's material.
Źródło:
Acta Physica Polonica A; 2012, 121, 1A; A-100-A-109
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Total Acoustic Power of a Clamped Circular Plate Located at the Boundary of Three-Wall Corner Region
Autorzy:
Szemela, K.
Rdzanek, W.
Pieczonka, D.
Powiązania:
https://bibliotekanauki.pl/articles/1504426.pdf
Data publikacji:
2011-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
43.20.Ks
43.20.Rz
43.40.+s
43.20.-f
43.20.+g
Opis:
The energetic aspect of the sound radiation has been analyzed in the case of the three-wall corner region. This region is the part of space bounded by three baffles arranged perpendicularly to one another. The Neumann boundary value problem has been solved assuming that the sound source is the vibrating circular plate embedded in one of the baffles of the three-wall corner region. The Kelvin-Voigt theory of a visco-elastic plate has been used which allows to include internal attenuation existing in the plate material. It has been assumed that the sound source is excited to vibrations by the external pressure asymmetrically distributed on the plate surface. The modal coefficients of the acoustic impedance have been obtained in the form of the expressions containing single integrals only. The formula describing the acoustic power of the analyzed sound source has been presented as a fourfold infinite series containing the modal coefficients of the acoustic impedance. The influence of some asymmetric excitations on the acoustic power has been analyzed. The possibilities of the modelling some uniform excitations located on the plate fragment of the small area by the point force excitation has been examined. The influence of the transverse baffles on the acoustic power has also been investigated. It has been determined for which frequency the baffles influence on the acoustic power is the greatest.
Źródło:
Acta Physica Polonica A; 2011, 119, 6A; 1050-1060
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structural and Optical Characterisation of Hydrogenated Soda-Lime Silicate Glasses Doped with Silver and Copper
Autorzy:
Suszyńska, M.
Krajczyk, L.
Macalik, B.
Powiązania:
https://bibliotekanauki.pl/articles/2037038.pdf
Data publikacji:
2003-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.43.Fs
64.75.+g
68.37.Lp
78.20.-e
78.40.Ha
Opis:
The results of comparative studies of the effect of hydrogenation upon structural and optical properties of the commercial soda-lime silicate glasses doped either with monovalent silver or copper have been presented. The samples were characterised by means of the scanning and transmission electron microscopy and the UV-VIS-IR absorption spectroscopy. It has been shown that the annealing of suitably ion-exchanged specimens in gaseous hydrogen atmosphere could be considered as an effective procedure for obtaining composite materials of expected properties correlated with the induced changes of the morphology of both the glassy matrix and the dopant.
Źródło:
Acta Physica Polonica A; 2003, 104, 6; 559-569
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
NiTi shape memory marformed alloy studied by electron beam precession TEM orientation mapping method
Autorzy:
Świec, P.
Zubko, M.
Lekston, Z.
Stróż, D.
Powiązania:
https://bibliotekanauki.pl/articles/1055112.pdf
Data publikacji:
2017-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
62.20.fg
62.20.F-
61.43.Dq
61.66.Bi
68.37.Ef
62.25.-g
64.70.Nd
Opis:
Severe plastic deformation by cold-rolling in martensitic state was applied to Ni_{50.4}Ti_{49.6} shape memory alloy. Received materials with 17, 20, 25, and 35% deformation were further annealed at 450°C for 15 min. After such treatment hardness of this alloy increased significantly reaching 365 HV0.5 for highest deformation degree. Calorimetric studies revealed two-stage and two-step character of martensitic transformation occurring in all specimens. Nanocrystalline structure with average grain size 53, 34, 28, and 24 nm was obtained. In material with 35% of deformation amorphous regions containing a nuclei of B2 parental phase with average size of 5 nm were observed. To determine the crystallographic orientation of observed nanograins and for better phase analysis, electron beam precession transmission electron microscopy orientation mapping was performed.
Źródło:
Acta Physica Polonica A; 2017, 131, 5; 1307-1310
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-5 z 5

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies