Informacja

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

Wyszukujesz frazę "ł." wg kryterium: Autor


Tytuł:
Road to Quantum Boxes
Autorzy:
Chang, L. L.
Powiązania:
https://bibliotekanauki.pl/articles/1946514.pdf
Data publikacji:
1996-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
73.61.-r
78.66.-w
Opis:
Quantum wells and superlattices have evolved over the last two decades to become a prominent multi-disciplinary field in condensed matter science. From the first observation of resonant tunneling to the recent realization of the quantum box, in this work we provide a summary description of the historical development of the field, known today as quantum structures. The focus is on the physics aspect with emphasis on important experimental observations that collectively define the field and set its direction of development.
Źródło:
Acta Physica Polonica A; 1996, 90, 4; 603-612
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Magnetic Properties and the Barkhausen Noise of the Hydrogenated Fe-V-B Amorphous Alloy
Autorzy:
Ceniga, L.
Novák, L.
Powiązania:
https://bibliotekanauki.pl/articles/2013242.pdf
Data publikacji:
2000-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.43.Dq
75.50.Kj
75.60.Ej
Opis:
As a consequence of the hydrogenation-dehydrogenation process, in the present paper the study of structural changes which could be followed by measuring structure sensitive magnetic properties as the stress induced anisotropy, the coercive force, the demagnetizing factor, and the Barkhausen noise parameters of the as-cast and hydrogenated Fe$\text{}_{80}$V$\text{}_{5}$B$\text{}_{15}$ amorphous alloys is performed.
Źródło:
Acta Physica Polonica A; 2000, 97, 3; 611-614
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nuclear Magnetic Resonance Investigation of the Influence of Drawing and Drawing Temperatureon Molecular Mobility in iPP Fibres
Autorzy:
Mucha, L'.
Ševčovič, L.
Powiązania:
https://bibliotekanauki.pl/articles/1535491.pdf
Data publikacji:
2010-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
76.60.Es
82.35.Lr
82.56.Nc
Opis:
A set of stretched isotactic polypropylene fibres prepared with the draw ratio λ = 2.5 at different temperatures was investigated by $\text{}^1H$ pulsed relaxation NMR method and continuous wave spectroscopy. Both, drawing and temperature of drawing influence physical properties of isotactic polypropylene fibres. NMR technique is shown to be advantageous for the study of these changes on molecular level since the shape of broad-line NMR spectra and processes of the NMR relaxation depend on the spatial configuration and motions of the resonating nuclei.
Źródło:
Acta Physica Polonica A; 2010, 118, 5; 1057-1058
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis and Luminescent Properties of $Eu^{3+}$ Doped Crystalline Diphosphate $Na_2ZnP_2O_7$
Autorzy:
Guerbous, L.
Gacem, L.
Powiązania:
https://bibliotekanauki.pl/articles/1418919.pdf
Data publikacji:
2012-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.20.-e
78.55.-m
78.55.Hx
Opis:
Undoped and $Eu^{3+}$-doped disodium zinc diphosphate $Na_2ZnP_2O_7$ (NZPO) single crystals are grown by the Czochralski method. X-ray diffraction, Fourier transform infrared and Raman techniques were used to check the crystallographic structure. Excitation and emission spectra were measured at room temperature and studied. The $Eu^{3+}$ ions occupy a non-centrosymmetric site with different coordination number. Very efficient energy transfer from $O-Eu^{3+}$ band state to $Eu^{3+}$ excited energy levels is highlighted.
Źródło:
Acta Physica Polonica A; 2012, 122, 3; 535-538
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Neuro-Adaptive Learning (NAL) Approach about Costs of Residential Buildings
Autorzy:
Ugur, L.
Powiązania:
https://bibliotekanauki.pl/articles/1031585.pdf
Data publikacji:
2017-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
costs of residential buildings
neuro-adaptive learning
fuzzy logic
Opis:
The artificial neural networks and fuzzy logic models are two well-known branches of artificial intelligence and have been broadly and successfully used to simulate input-output systems. Over the last two decades, a different modeling method based on fuzzy logic or neural networks has become popular and has been used by many researchers for a variety of engineering applications. Nowadays, for reducing the amount of experiment costs, modeling methods based on artificial neural networks and fuzzy logic systems have become more popular and have been used by many researchers for many civil engineering management applications. In this study a neuro-adaptive learning approach about costs of residential buildings was designed. As a result, NAL can be an alternative approach for the evaluation of the cost estimations of residential buildings construction.
Źródło:
Acta Physica Polonica A; 2017, 132, 3; 585-587
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation study of topological point defects in graphitic layer - curvature effect and pair correlation function analysis
Autorzy:
Hawelek, L.
Powiązania:
https://bibliotekanauki.pl/articles/1075560.pdf
Data publikacji:
2016-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.05.ue
61.72.J-
61.43.Bn
61.66.Fn
61.05.C-
Opis:
The effect of three types of topological defects, single vacancy, double vacancy and the Stone-Thrower-Wales defect on the atomic arrangement in a single graphitic layer is studied using computer simulations. The topological defects were positioned on the perfect hexagonal graphitic layer 20 Å in diameter with different distance from the layer edge and then the geometry of the system was independently optimized using the reactive bond order potential, the semi-empirical quantum-chemical PM7 and the density functional theory method. Curvature and the distortion of the graphitic layer caused by the defects are analyzed and their influence on the pair correlation function is discussed.
Źródło:
Acta Physica Polonica A; 2016, 130, 3; 811-816
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Critical View on the Creep Modelling Procedures
Autorzy:
Kloc, L.
Powiązania:
https://bibliotekanauki.pl/articles/1402073.pdf
Data publikacji:
2015-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
62.20.Hg
87.10.Kn
81.40.Lm
Opis:
Process of creep deformation is rather complex, consisting of many interconnected subprocesses, mainly: (i) the creep strain itself, based on dislocation mobility as well as grain boundary activity, (ii) development of dislocation substructure (work strengthening and dynamic recovery), (iii) development of phase structure (phase transformations, precipitation, particle coarsening, etc.), and (iv) nucleation and development of voids and microcracks, i.e. creep damage. The creep experiments are time consuming and expensive, moreover, it is not possible to make experiments under the service conditions of particular materials due to very slow creep strain, the process seems to be ideal field for computer modelling. The experimental data are obviously available for the steady conditions only, so the effects of varying conditions during startup or shutdown of the components can be described by modelling. The model of creep deformation is obviously based on the so-called "creep constitutive equation", which should describe the strain rate dependence on stress, temperature and some other variables. Nevertheless, the comprehensive physical description of all the above mentioned processes is still missing. This paper should illustrate the shortcomings of most "creep constitutive equations", confronting them to some experimental results on common structural materials under non-steady loading conditions.
Źródło:
Acta Physica Polonica A; 2015, 128, 4; 540-542
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermodynamics of the Exactly Solvable Spin-Electron Tetrahedral Chain
Autorzy:
Gálisová, L.
Powiązania:
https://bibliotekanauki.pl/articles/1402558.pdf
Data publikacji:
2015-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
05.70.-a
75.10.Pq
Opis:
An exactly solvable spin-electron tetrahedral chain, where the Ising spins localized at nodal lattice sites regularly alternate with three equivalent lattice sites available for one mobile electron is considered. The system with ferromagnetic interaction between the Ising spins and electrons exhibits an enhanced magnetocaloric effect in the limit H/|J| → 0 when the entropy is very small, whereas the system with antiferromagnetic interaction between the Ising spins and electrons exhibits an enhanced magnetocaloric effect around the field H/J=1 when the entropy is sufficiently close to the value S/2N = ln[(1+√5)/2]. We study the thermodynamics of the system in these field regions.
Źródło:
Acta Physica Polonica A; 2015, 128, 2; 156-158
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multimodal Transition and Excitability of a Neural Oscillator
Autorzy:
Borkowski, L.
Powiązania:
https://bibliotekanauki.pl/articles/1418345.pdf
Data publikacji:
2012-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
87.19.lb
87.19.ll
87.19.ln
Opis:
We analyze the response of the Morris-Lecar model to a periodic train of short current pulses in the period-amplitude plane. For a wide parameter range encompassing both class 2 and class 3 behavior in the Hodgkin classification there is a multimodal transition between the set of odd modes and the set of all modes. It is located between the 2:1 and 3:1 locked-in regions. It is the same dynamic instability as the one discovered earlier in the Hodgkin-Huxley model and observed experimentally in squid giant axons. It appears simultaneously with the bistability of the states 2:1 and 3:1 in the perithreshold regime. These results imply that the multimodal transition may be a universal property of resonant neurons.
Źródło:
Acta Physica Polonica A; 2012, 122, 4; 776-780
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Scaling of Dependence between Foreign Exchange Rates and Stock Markets in Central Europe
Autorzy:
Kristoufek, L.
Powiązania:
https://bibliotekanauki.pl/articles/1398833.pdf
Data publikacji:
2016-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
05.45.Tp
89.75.Da
89.65.Gh
Opis:
We propose two novel methodological approaches - the detrending moving average based regression coefficient estimator and the scale-dependent instrumental variable estimator - and show their utility on a specific case of dependence between stock markets and connected foreign exchange rates in the Central European region - the Czech Republic, Hungary, and Poland. The methodology has proven useful as we uncovered several interesting findings such as scale dependence of the shock transmission and differences between the Euro and U.S. dollar currency pairs. The Polish currency is also the most sensitive of the three with respect to the stock market shocks. The proposed methodology can be applied to any system with potential endogeneity issues if one is interested in the scale variability of the effect of interest.
Źródło:
Acta Physica Polonica A; 2016, 129, 5; 908-912
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Properties of ZnO and Zn(Cd)O Fullerene-Like Clusters with a Shell of Diamond-Like Structure with $ \text{sp}^{2}//\text{sp}^{3}$ Bonds
Autorzy:
Ovsiannikova, L.
Powiązania:
https://bibliotekanauki.pl/articles/1399133.pdf
Data publikacji:
2013-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.22.-f
78.55.Et
81.05.Dz
81.07.Bc
Opis:
The structural, cohesive, and electronic properties of a fullerene-like $(ZnO)_{60}$ cluster with a shell of diamond-like structure with $\text{sp}^2//\text{sp}^3$ bonds have been investigated in comparison with those of clusters differing in geometry and composed of the equal number of ZnO structural units (clusters of fullerene, onion, and coordination tetrahedron) within the framework of the electron density hybride functional method (B3LYP) with a set of 6-31G(d) split valence basis functions. The fullerene-like $(ZnO)_{60}$ cluster is used as a model in an investigation of the change in the band-gap width (the decrease in the band-gap width is ≈ 0.2 eV) in the case of the substitution of Zn atoms by Cd atoms (20% of substitution) in the ZnO matrix in ZnCdO ternary structures.
Źródło:
Acta Physica Polonica A; 2013, 124, 5; 862-864
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Overall Model of Plasticity and Failure of Metals
Autorzy:
Zuev, L.
Powiązania:
https://bibliotekanauki.pl/articles/1503735.pdf
Data publikacji:
2011-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
62.20.fq
61.72.-y
62.20.mt
Opis:
Plastic flow evolution was investigated for various metals and alloys, which differed in chemical bond and crystal lattice type (BCC/FCC/HCP), structural state (single-crystal/polycrystalline) and deformation mechanisms (dislocation glide/twinning). On the base of conclusive evidence it is attempted to explain the phenomenon of plastic flow localization by invoking a fundamental principle of quantum mechanics.
Źródło:
Acta Physica Polonica A; 2011, 120, 2; 340-343
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Investigation of the Cadmium Effect on Properties of ZnCdO Alloys Using $Zn_{36-x}Cd_{x}O_{36}$ Clusters
Autorzy:
Ovsiannikova, L.
Powiązania:
https://bibliotekanauki.pl/articles/1375895.pdf
Data publikacji:
2014-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.22.-f
78.55.Et
81.05.Dz
81.07.Bc
Opis:
The structural, cohesive, and electronic properties of a fullerene-like $Zn_{n-x}Cd_{x}O_{n}$ (n=36) clusters have been investigated within the framework of the electron density hybride functional method (B3LYP) with a set of 3-21G(d) split valence basis functions. These clusters are used as a model in an investigation of the change in the band-gap width in the case of the substitution of Zn atoms by Cd atoms in the ZnO matrix in ZnCdO ternary structures. The presented investigations showed that a substitution of Zn atom to Cd (5.5, 11, 16.7, 22 and 33 at.% Cd) leads to reduction of cluster stability and monotonous decrease of energy gap (0.145, 0.259, 0.354, 0.436, 0.586 eV, accordingly).
Źródło:
Acta Physica Polonica A; 2014, 126, 5; 1090-1092
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Diffraction of Light by Finite Amplitude Ultrasonic Waves
Autorzy:
Adler, L.
Powiązania:
https://bibliotekanauki.pl/articles/1377935.pdf
Data publikacji:
2015-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
43.25.Ba
43.35.Sx
Opis:
In the late 1950s the Ultrasonic Group at Michigan State University introduced light diffraction to study distortion of ultrasonic waves in liquids under the direction of Prof. Egon Hiedemann. In this paper some results of these studies will be presented with detailed description of the author's measurements of B/A. The rate at which the harmonics are developed (the wave distortion is an indication of the harmonics present) during the propagation of the initially sinusoidal ultrasonic wave depends on the nonlinearity of the medium. The light which is diffracted by the distorted wave results in asymmetric pattern contrary to the Raman-Nath theoretical prediction. From the light intensity measurements due to the generated second harmonics - filtered out by a metal plate - the nonlinearity parameter B/A was determined. Developments in studying finite amplitude standing ultrasonic waves in a liquid filled cavity will be also discussed. Using light diffraction measurements it was observed that above a threshold amplitude, fractional harmonics of the driver transducer are also generated in addition to the generated harmonics. It was recently observed that above a second threshold value of the driver amplitude the system undergoes chaotic behavior. Further increase of the driver amplitude returns the system from chaos to stable oscillation.
Źródło:
Acta Physica Polonica A; 2015, 127, 1; 5-9
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
What Is Unique About Mechanochemical Reactions?
Autorzy:
Takacs, L.
Powiązania:
https://bibliotekanauki.pl/articles/1383095.pdf
Data publikacji:
2014-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.20.Ev
82.33.Pt
82.30.-b
Opis:
Mechanochemical reactions can provide compounds, phases, and microstructures that are essentially different from the products of ordinary reactions. In this paper, the origin of this uniqueness is discussed in light of the recent advances of the field. It is claimed that the local availability of large batches of energy, well above kT, is the key feature of mechanochemical reactions. As a consequence, reactions that cannot occur thermally become possible, similarly to the reactions induced by the energy of photons in photochemistry. However, the situation is more complex, as macroscopic deformation affects many defect sites simultaneously. The direction of the mechanical load relative to the orientation of a molecule or the crystallographic axes of a solid can be important. Many mechanochemical reactions of organic compounds take place at low milling energy that is not sufficient to break primary bonds, but the gentle mechanical grinding can influence the relative position of macromolecules, leading to the formation of unique cocrystals and compounds. In inorganic systems, unusual products form due to forced mixing and the high defect density generated by intense milling.
Źródło:
Acta Physica Polonica A; 2014, 126, 4; 1040-1043
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł

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