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1
Content available Application of the interval Lattice Boltzmann method for a numerical modeling of 2D thin metal films irradiated by ultrashort laser pulses
Piasecka-Belkhayat Alicja, Korczak Anna
Journal of Applied Mathematics and Computational Mechanics
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2019
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Vol. 18, nr 4
63--71
EN
In the paper, the two-dimensional numerical modelling of heat transfer in thin metal films irradiated by ultrashort laser pulses using the D2Q9 scheme is considered. In the mathematical description, the relaxation times and the boundary conditions for phonons and electrons are given as interval numbers. The problem has been formulated using the interval coupled lattice Boltzmann equations for electrons and phonons. The solution has been obtained by means of the interval lattice Boltzmann method using the rules of directed interval arithmetic. Examples of numerical computations are presented in the final part of the paper.
2
Content available Variation of temperature field created at pulsed laser irradiation of amorphous Fe73.7Si15.5B7.4Nb2.4Cu1.0 alloy
Nykyruy Yu.S., Mudry S. I.
TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk
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2015
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Vol. 19, No 1
75--82
EN
The temperature in the laser irradiation area of an amorphous iron-based ribbon was calculated. As a result of the calculation a spatial temperature distribution and its time dependence were structured which allowed reproducing the geometric and structural characteristics of exposed areas. Simultaneously, an irradiated amorphous alloy was investigated by scanning electron microscopy which allowed determining the geometric and structural characteristics of these areas experimentally and obtaining their dependencies on the laser pulse parameters. The results of theoretical calculations were compared with the experimental data.
3
Content available Modelling of thermal damage in laser irradiated tissue
Jasiński M.
Journal of Applied Mathematics and Computational Mechanics
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2015
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Vol. 14, nr 4
67--78
EN
In the paper the numerical analysis of thermal processes proceeding in the 2D homogeneous biological tissue subjected to laser irradiation is presented. In particular, the influence of necrotic changes in tissue on the values of the perfusion coefficient and effective scattering coefficient are discussed. The transient heat transfer is described by the bioheat transfer equation in the Pennes formulation. As a model of light distribution in tissue, the first-order scattering approach has been used. At the stage of numerical realization the 1st scheme of the boundary element method has been applied.
4
Content available remote Laser induced structure transformation in Co70Fe3Mn3.5Mo1.5B11Si11 amorphous alloy
Mudry S. I., Nykyruy Yu.S.
Materials Science Poland
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2014
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Vol. 32, No. 1
28--33
EN
Laser induced structure changes in amorphous Co70Fe3Mn3:5Mo1:5B11Si11 alloy have been studied by means of X-ray diffraction and magnetic properties measurements. Both three types of structural relaxations and a starting stage of crystallization process are considered as main characteristics of structure transformation upon laser treatment. Results of investigation of this amorphous alloy at different parameters of laser irradiation have shown that this alloy becomes partly crystalline after irradiation with laser pulse fluence of about 1.8 J/mm2 and pulse duration t = 2 × 10-5 sec. Increasing of laser pulse fluence above 2.0 J/mm2 leads to the destruction of ribbon, due to intensive evaporation.
5
Content available Laser photoacoustic diagnostics of advanced materials with different structure and dimensions
Burbelo R., Andrusenko D., Isaiev M., Kuzmich A.
Archives of Metallurgy and Materials
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2011
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Vol. 56, iss. 4
1157-1162
EN
In the article the results of practical implementation of the PA methods in the study of materials of different structure and dimensions are presented. The features of PA conversion in inhomogeneous semiconductor structures such as porous silicon and doped semiconductor materials are analyzed. To investigate the thermal and elastic properties of porous silicon's based composites gas-microphone and piezoelectric methods registration of PA signal were used. The results of theoretical and experimental investigation of PA conversion in inhomogeneous silicon-based semiconductor structures under their irradiation by short (~ 10 ns) laser pulse are presented. The influence of thermal parameters distribution of the material structure on the PA signal parameters is shown. Principal possibility of using pulsed radiation for investigation of the modified submicron surface layer is demonstrated.
PL
W pracy zaprezentowano wyniki praktycznej realizacji metod fotoakustycznych do badania materiałów o różnej strukturze i geometrii. Analizowane były aspekty konwersji fotoakustycznej w niejednorodnych strukturach półprzewodnikowych jak porowaty krzem i domieszkowane materiały półprzewodnikowe. Do badania termicznych i elastycznych właściwości kompozytów opartych na porowatym krzemie używano mikrofonowej, piezoelektrycznej metody fotoakustycznej. Przedstawione zostały wyniki teoretycznych i doświadczalnych badań konwersji fotoakustycznej przy użyciu krótkich impulsów laserowych (około 10 ns). Pokazano wpływ profilu przestrzennego materiałowych parametrów termicznych na sygnał fotoakustyczny. Przedstawiono także możliwości zastosowania metod impulsowych do badania submikronowych warstw powierzchniowych.
6
Content available remote Modeling of the processes of low-dimensional structures formation on semiconductors surface by scanning laser radiation
Manak I., Medvid A., Panfilionak E., Wójcik W.
Przegląd Elektrotechniczny
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2010
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R. 86, nr 7
139-141
EN
The analysis of results of experiment in the formation of periodic structures on GaAs surface by powerful laser radiation was conducted. The physic model of the process of structures formation was proposed. The numerical calculations of heating and melting processes of near-surface region was conducted.
PL
W pracy przeprowadzono analizę wyników eksperymentu obejmującego tworzenie struktur periodycznych na powierzchni GaAs za pomocą silnej radiacji laserowej. Zaproponowano fizyczny model procesu formowania struktur. Przedstawiono obliczenia numeryczne procesów ogrzewania i topienia obszarów przypowierzchniowych.
7
Content available remote Numerical modeling of tissue coagulation during laser irradiation controlled by surface temperature
Jasiński M.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2010
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Vol. 9, nr 1
29-36
EN
The numerical analysis of thermal process proceeding in biological tissue during a laser irradiation controlled by surface temperature of tissue is presented. Heat transfer in the tissue is assumed to be transient and one-dimensional. The internal heat sources resulting from laser irradiation based on the Beer law are taken into account. Perfusion rate and effective scattering coefficient are treated as dependent on tissue injury. At the stage of numerical computations the boundary element method has been used. In the final part of paper the results obtained are shown.
8
Content available remote Sensitivity analysis of bioheat transfer in human cornea subjected to laser irradiation. Part 2, Shape variation
Jasiński M.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2009
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Vol. 8, nr 1
71-76
EN
The paper is continuation of part 1, in which the sensitivity analysis with regard to the thermophysical and optic parameters of human cornea have been discussed. Numerical analysis of thermal processes proceeding in the domain of human cornea subjected to laser irradiation is presented. Heat transfer in the tissue domain was assumed to be transient and one-dimensional. The internal heat sources resulting from laser irradiation based on the Beer law are taken into account. The paper deals with sensitivity analysis of temperature field with respect to the geometrical parameters of cornea. At the stage of numerical computations the boundary element method has been used. In the final part of paper the results of computations are presented.
9
Content available remote Sensitivity analysis of bioheat transfer in human cornea subjected to laser irradiation. Part 1, Variation of optical parameters
Jasiński M.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2009
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Vol. 8, nr 1
63-70
EN
The numerical analysis of thermal process proceeding in the human cornea due to a laser irradiation is presented. Heat transfer in the cornea is assumed to be transient and one dimensional. The internal heat sources resulting from laser irradiation based on the Beer law are taken into account. The paper deals with sensitivity analysis of temperature field with respect to the optical and thermophysical parameters of cornea. At the stage of numerical computations the boundary element method has been used. In the final part of paper the results obtained are shown.
10
Content available Dynamics of laser-induced melting and modification of the surface of semiconductors by nanosecond laser pulses
Gnatyuk V., Aoki T., Vlasenko O., Gorodnychenko O.
Journal of Automation Mobile Robotics and Intelligent Systems
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2009
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Vol. 3, No. 4
33-36
EN
In situ detection and dynamics of laser-induced melting in different semiconductor crystals (CdTe, CdHgTe, GaAs, InSb and SiC) were performed by the time-resolved reflectivity (TRR). The samples were subjected to irradiation with 20 ns pulses of KrF excimer or ruby laser with energy density varied in a wide range. The surface morphology of the crystals was monitored using optical microscopy and time dependences of the temperature of the crystal surface as a function of laser pulse energy density was also calculated. The melting and ablation threshold values were determined and specific features of the laser-induced phase transitions in the surface region of the semiconductors were analyzed.
11
Content available remote Wpływ promieniowania laserowego na cienkie błony kolagenowe. Cz. I. Mechanizm tworzenia struktury "mikropianki" i ablacja powierzchni kolagenu
Wiśniewski M., Sionkowska A., Kaczmarek H., Lazare S., Tokarev V.
Polimery
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2007
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T. 52, nr 4
259-267
PL
Cienkie błony kolagenowe poddawano działaniu lasera ekscymerowego KrF (γ=248nm). Za pomocą skaningowej mikroskopii elektronowej (SEM) oraz mikroskopii sił atomowych (AFM) oceniono wpływ napromieniania na powierzchnię błony. Ubytki masy materiału w wyniku procesu ablacyjnego wyznaczono wykorzystując mikrowagę kwarcową (metodą QCM). Napromienianie laserowe suszonych błon kolagenowych (15% pozostałości wody) wywołuje "spienienie" powierzchni już po zastosowaniu tylko jednego impulsu. Omówiono mechanizm tworzenia struktury "mikropianki" polegający na nukleacji pęcherzyków oraz ich wzroście, co jest możliwe w następstwie spadku ciśnienia aż do powstania naprężenia rozciągającego przekraczającego wytrzymałość błony kolagenowej. Zjawisko to jest powodowane przez dwubiegunową falę ciśnieniową tworzącą się w powierzchniowej sekwencji "przyspieszanie-opóźnianie" w kierunku działania wiązki promieniowania laserowego.
EN
Thin collagen films were subjected to KrF excimer laser irradiation (γ= 248nm). The effect of irradiation on the film surface was evaluated using scanning electron microscopy (SEM) (Fig. 1-6) and atomic force microscopy (AFM) (Fig. 8, 9). Material weight loss, as a result of ablative process, was determined using quartz crystal microbalance (QCM method) (Table 1). Laser irradiation of dried collagen films (15% of residual water) caused "foaming" of the surface just after use of one pulse. The mechanism of "micro-foam" formation based on the nucleation and growth of the bubbles, possible as aresult of pressure drop causing tensile stress exceeding the strength of collagen film (Fig. 7), was discussed. This phenomenon is caused by bipolar pressure wave formed due to the surface "acceleration-deceleration" sequence towards the laser beam direction.
12
Content available remote Wpływ promieniowania laserowego na cienkie błony kolagenowe. Cz. II, Badania spektroskopowe struktury „mikropianki” kolagenowej
Wiśniewski M., Sionkowska A., Kaczmarek H., Lazare S., Tokarev V.
Polimery
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2007
|
T. 52, nr 7-8
571-578
PL
Szczegółowo scharakteryzowano specyficzną strukturę kolagenu i na tej podstawie zinterpretowano - określony metodami spektroskopii Ramana oraz FTIR-ATR - wpływ energii i liczby impulsów lasera ekscymerowego KrF (&lambda=248nm) na uporządkowanie struktury błon kolagenowych. Stwierdzono, że napromienianie laserem powoduje zanik oddziaływań krótkiego zasięgu (wiązania wodorowe, oddziaływania van der Waalsa i hydrofobowe) oraz ubytek wody. W wyniku tych zjawisk potrójna helisa kolagenu po części przechodzi w strukturę kłębka statystycznego. Ponadto widma ramanowskie wskazują na reakcje rozmywania wiązań łańcucha głównego cząsteczek kolagenu wywołane dużą wartością energii (5eV) fotonów zastosowanego lasera.
EN
Specific structure of collagen was characterized in detail (Scheme A, B and C). On this basis the interpretation of the effects of energy and number of pulses of excimer laser KrF (?=248nm) on the collagen film structure array (Fig. 1-5, Table 1) (determined by Raman and FTIR-ATR spectroscopic methods) has been done. The decay of short range interactions (hydrogen bonds, Van der Waals forces and hydrophobic interactions) as well as water loss were found. As a result of all this the triple helix of collagen partially change the structure to random coil. Additionally, the Raman spectra suggest the reactions of chain scission of collagen caused by high energy of photons (5eV) of the laser used.
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