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1

Numerical Approach to Predicting Thermodynamic Properties of Ternary Al-Ni-Pt Alloys

100%

Zagula-Yavorska M., Romanowska J., Kotowski S., Sieniawski J.

Acta Physica Polonica A

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2015

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vol. 127

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issue 6

1573-1576

EN

Thermodynamic properties of ternary Al-Ni-Pt system, such as ^{ex}G_{AlNiPt}, μ_{Al(AlNiPt)}, μ_{Ni(AlNiPt)}, and μ_{Pt(AlNiPt)} at 1373 K were predicted on the basis of thermodynamic properties of binary systems included in the investigated ternary system. The idea of predicting ^{ex}G_{AlNiPt} values was regarded as calculation of values of ^{ex}G function inside a certain area (a Gibbs triangle) unless all boundary conditions, that is values of ^{ex}G on all legs of the triangle are known (^{ex}G_{AlNi}, ^{ex}G_{AlPt}, ^{ex}G_{NiPt}). This approach is contrary to finding the function value outside a certain area, if the function value inside this area is known. ^{ex}G and L_{ijk} ternary interaction parameters in the Muggianu extension of the Redlich-Kister formalism are calculated numerically using the Mathematica program. The accepted values of the third component concentration x_{x} differed from 0.01 to 0.1 mol fraction. Values of L parameters in the Redlich-Kister formula vary for different x_{x} values, the ^{0}L_{AlNiPt} value in particular. Values of thermodynamic functions: ^{ex}G_{AlNiPt}, μ_{Al(AlNiPt)}, μ_{Ni(AlNiPt)} and μ_{Pt(AlNiPt)} do not differ significantly for different x_{x} values. The choice of x_{x} value does not influence the accuracy of calculations.

2

Multispectral Laser Head for Terrain Identification and Analysis

80%

Mierczyk Z., Zygmunt M., Kaszczuk M., Muzal M.

Acta Physica Polonica A

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2013

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vol. 124

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issue 3

502-504

EN

The reflectance profilometer, constructed in Institute of Optoelectronics, Military University of Technology, is an optoelectronic device based on the laser remote sensing technique, designed for use on unmanned aerial vehicles. The main task of the profilometer is to analyze the reflectance signals for laser radiation from the multispectral range: 850, 905, and 1550 nm. On the basis of the analysis the profilometer enables two fundamental functions: to define the shape of the ground and identify elements of terrain coverage, along with analysis of its physicochemical properties. The reflectance profilometer is a system based on a modern concept of measurement, allowing to obtain unique information about tested objects, whose measurements or detection are not possible by means of thermal imaging systems and systems operating in the visible range. The received information is visualized in 3D format, which allows for more accurate, precise and comprehensive way of analyzed area model presentation.

3

The Variational Calculation of Bulk Moduli for Liquid Binary Alloys of Alkali Metals

80%

Dubinin N.

Acta Physica Polonica A

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2017

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vol. 131

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issue 2

237-239

EN

The bulk moduli of the Na-K, Na-Cs, and K-Rb liquid equiatomic alloys at T=373 K are calculated by the variational method with the hard-sphere reference system. The local Animalu-Heine model pseudopotential and Toigo-Woodruff exchange-correlation function are used for the calculation. A good agreement with experimental data is achieved.

4

Effect of Different SU(3) Color Representations on the Nucleation of Quark-Gluon Plasma Droplets from a Hadronic Gas

80%

Mezouar K., Ait El Djoudi A.

Acta Physica Polonica A

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2016

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vol. 130

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issue 1

202-205

EN

We study the nucleation of quark-gluon plasma (QGP) droplets from the hadronic gas phase, based on the calculation of the difference in free energy in the QGP and hadronic gas phases. We investigate this difference in free energy by modeling it in different cases, when the surface tension of the QGP bubble is considered or not. We calculate the free energies of both hadronic gas consisting of massive pions and plasma droplet with up, down and strange quarks additionally to gluons, for different SU ≤ft( 3 ıght) color representations of the QGP, namely the color singlet, color octet, and color 27-plet. The behavior of the obtained change in free energy is examined with varying radius of the QGP bubble, and at different temperatures. The effect of the surface contribution on the nucleated bubble is also investigated and compared to the case without this contribution.

5

In Quest of the Best Theoretical Description of Excess Molar Functions οf Binary Mixtures of Alcohols

80%

Geppert-Rybczyńska M., Hofman T.

Acta Physica Polonica A

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2008

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vol. 114

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issue 6A

A-91-A-96

EN

An attempt to describe excess molar functions of alkane + alcohol and alcohol + alcohol binary mixtures was made using the theoretical approach constructed on the basis of S-ERAS model and the chemical theory proposed by Campbell. The results obtained seem to be promising, however in order to complete the work, the procedure of determination of fitting parameters as well as relative magnitude of physical and chemical contributions to regarded excess molar quantities must be established.

6

Kinetically-Driven Frustration in Hybrid Spin Ladders

80%

Carvalho R., Pereira M., Lyra M., Rojas O., Strecka J.

Acta Physica Polonica A

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2014

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vol. 126

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issue 1

12-13

EN

We introduce a spin ladder model incorporating localized and delocalized spins, which is exactly solvable using the decoration-iteration and transfer-matrix techniques. Quantum correlations between delocalized spins induce an antiferromagnetic coupling between the spin chains that competes with a direct ferromagnetic exchange coupling. A resulting kinetically-driven frustration is predominant in the regime of low temperatures and large hopping amplitudes. We provide the full ground-state phase diagram, as well as the frustration diagram on distinct coupling regimes.

7

Excess thermodynamic quantities of D2O water calculated from its Raman O−D stretching spectra

61%

Georgiev M., Goutev N., Nickolov Z., Georgiev G.

Open Physics

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2005

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vol. 3

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issue 1

104-114

EN

Excess thermodynamic functions of D2O water have been calculated from the vibrationally decoupled O−D stretching spectra of very dilute solutions of HOD in H2O. Comparison of the results with reference calorimetric data for water showed a good correspondence for excess heat capacity above the melting point of ice. The excess enthalpy at the melting point also coincides well with latent heat of melting.

8

Exact Diagonalization Study of an Extended Hubbard Model for a Cubic Cluster at Quarter Filling

61%

Szałowski K., Balcerzak T., Jaščur M., Bobák A., Žukovič M.

Acta Physica Polonica A

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2017

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vol. 131

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issue 4

1012-1014

EN

In the paper the thermodynamics of a cubic cluster with 8 sites at quarter filling is characterized by means of exact diagonalization technique. Particular emphasis is put on the behaviour of such response functions as specific heat and magnetic susceptibility. The system is modelled with extended Hubbard model which includes electron hopping between both first and second nearest neighbours as well as Coulombic interactions, both on-site and between nearest-neighbour sites. The importance of hopping between second nearest neighbours and Coulombic interactions between nearest neighbours for the temperature dependences of thermodynamic response functions is analysed. In particular, the predictions of the Schottky model are compared with the calculations based on the full energy spectrum.

9

Study of a Mixed Hadronic-QGP System with Massive Particles

61%

Ghenam L., El Djoudi A.

Acta Physica Polonica A

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2015

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vol. 128

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issue 2B

B-341-B-343

EN

We consider a mixed system of hadronic and quark-gluon plasma (QGP) phases in a finite volume, and use a phenomenological approach with two phases matter equations of state to study the occurring deconfinement phase transition with varying temperature and/or chemical potential. We take into account massive particles in both phases, and calculate several physical quantities describing well the system at the phase transition. We probe the behaviour of these quantities, by examining their variations with temperature and volume at fixed chemical potential, as well as with chemical potential and volume at fixed temperature, in three dimensional plots, and obtain the finite size effects on the deconfinement phase transition.

Refine search results

Numerical Approach to Predicting Thermodynamic Properties of Ternary Al-Ni-Pt Alloys

Multispectral Laser Head for Terrain Identification and Analysis

The Variational Calculation of Bulk Moduli for Liquid Binary Alloys of Alkali Metals

Effect of Different SU(3) Color Representations on the Nucleation of Quark-Gluon Plasma Droplets from a Hadronic Gas

In Quest of the Best Theoretical Description of Excess Molar Functions οf Binary Mixtures of Alcohols

Kinetically-Driven Frustration in Hybrid Spin Ladders

Excess thermodynamic quantities of D2O water calculated from its Raman O−D stretching spectra

Exact Diagonalization Study of an Extended Hubbard Model for a Cubic Cluster at Quarter Filling

Study of a Mixed Hadronic-QGP System with Massive Particles