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Wyszukujesz frazę "61.10.-i" wg kryterium: Temat


Wyświetlanie 1-60 z 60
Tytuł:
Investigation of Misfit Dislocation Sources in GaAs Epitaxial Layers
Autorzy:
Wierzchowski, W.
Mazur, K.
Strupiński, Wł.
Wieteska, K.
Graeff, W.
Powiązania:
https://bibliotekanauki.pl/articles/1945232.pdf
Data publikacji:
1996-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
Opis:
The formation of misfit dislocation was studied in GaAs homoepitaxial layers on the substrates containing considerable amount of isoelectronic indium. The layers were grown with metal-oxide chemical vapour deposition and chemical vapour deposition methods including low temperature process with tertiarbutylarsine arsenic source. The critical conditions of misfit dislocation formation were exceeded up to 5×. The samples were examined before and after epitaxial process with a number of different X-ray topographic and diffractometric methods, including high resolution synchrotron white beam topography. The crystallographic identification of the defects was supported by the numerical simulation of topographic images. It was found that a number of threading dislocations, continuing in the epitaxial layer from those existing in the substrate, did not take part in the formation of misfit dislocations despite a suitable slip system. On the other hand, the formation of misfit dislocations from small imperfections of epitaxial deposit was proved in many cases. A reasonable good quality of the layers was confirmed by the resolution of individual defects and only small broadening of rocking curves.
Źródło:
Acta Physica Polonica A; 1996, 89, 3; 341-346
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
X-Ray Topographic Investigation of Cellular Structure and its Relation to another Defects in Various Types of GaAs Single-Crystals
Autorzy:
Wierzchowski, W.
Mazur, K.
Powiązania:
https://bibliotekanauki.pl/articles/1929756.pdf
Data publikacji:
1993-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
Opis:
The defect patterns in GaAs crystal grown using liquid encapsulated Czochralski and gradient freeze methods with various types of doping were characterized using complementary X-ray topographic methods. It was found that the cellular structure occurring in the low doped crystal is developed independently from the actual growth surface. The occurrence of the cellular structure is connected with significant lattice deformation, and some results point that significant stress can influence its formation. The high doping prevents formation of the cellular structure, but at higher doping the phenomenon of "cellular growth" can occur due to instabilities of the growth surface. The present results point that defect pattern in GaAs crystals is more affected by the type of doping than by the choice of the growth method.
Źródło:
Acta Physica Polonica A; 1993, 84, 4; 789-794
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
High-Temperature X-ray Diffraction Studies of Lattice Dynamics in Ni$\text{}_{3}$(Fe,Nb) Ordered Alloys
Autorzy:
Mekhrabov, A. O.
Powiązania:
https://bibliotekanauki.pl/articles/1930628.pdf
Data publikacji:
1994-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
Opis:
A study is performed on characteristics of lattice dynamics in the initially ordered ternary Ni$\text{}_{3}$(Fe$\text{}_{1-x}$Nb$\text{}_{x}$) (x = O to 10 at.%) alloys using high temperature X-ray diffractometry for the temperature range from 300 K to 1300 K. Aspects investigated included temperature and concentration dependencies of the full mean square atomic displacements Ū²$\text{}_{f}$, the Debye characteristic temperature Θ$\text{}_{D}$, and linear thermal expansion coefficient α. It is found that the Ū²$\text{}_{f}$, Θ$\text{}_{D}$, and α parameters show anomalous change at temperatures where the alloys are subjected to order-disorder phase transitions. It is further found that Nb addition results in the considerable increase in the parameters Ū²$\text{}_{f}$ and α and decrease in Θ$\text{}_{D}$. Moreover, the addition of Nb stabilizes Ni$\text{}_{3}$Fe ordered structure and shifts the order-disorder transition to higher temperature.
Źródło:
Acta Physica Polonica A; 1994, 85, 3; 571-578
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stereoscopic Observation of Synthetic Diamond with Haruta Stereo-Pairs of Synchrotron Transmission Double-Crystal Topographs
Autorzy:
Moore, M.
Lang, A. R.
Wierzchowski, W.
Powiązania:
https://bibliotekanauki.pl/articles/1931679.pdf
Data publikacji:
1994-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
Opis:
The Haruta method is used for stereoscopic observation of a 1.5 × 4 × 4 mm$\text{}^{3}$ cuboctahedral synthetic diamond with transmission double-crystal topography. The experiments were performed using a synchrotron double-crystal arrangement with asymmetrical diamond 220 reflection selecting 1.0 Å radiation. The appropriate Haruta pairs were matched from a series taken with positions on the rocking curve changed by small intervals. A reasonable stereoscopic effect was observed for most defect images, particularly dislocations, stacking faults and growth sector boundaries. It was established that some interference fringes do not produce good stereoscopic effects and appear on the exit surfaces of the diamond.
Źródło:
Acta Physica Polonica A; 1994, 86, 4; 613-616
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synchrotron White Beam Topographic Studies of Gallium Arsenide Crystals
Autorzy:
Wierzchowski, W.
Wieteska, K.
Graeff, W.
Powiązania:
https://bibliotekanauki.pl/articles/1964178.pdf
Data publikacji:
1997-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
Opis:
A series of samples cut out from different types of gallium arsenide crystals with low dislocation density were studied by means of white beam synchrotron topography. The investigation was performed with transmission and back-reflection projection methods and transmission section method. Some of the topographs in transmission geometry provided a very high sensitivity suitable for revealing small precipitates. The transmission section images significantly differed depending on the wavelength and absorption. In some cases a distinct Pendellösung fringes and fine details of dislocation and precipitates images were observed. It was possible to reproduce the character of these images by means of numerical simulation based on integration of Takagi-Taupin equations. Due to more convenient choice of radiation, synchrotron back-reflection projection topography provided much better visibility of dislocations than analogous methods realized with conventional X-ray sources.
Źródło:
Acta Physica Polonica A; 1997, 91, 5; 1015-1019
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
X-Ray Standing Wave Technique as a Tool in the Study of the Imperfect Crystals
Autorzy:
Pełka, J.
Auleytner, J.
Powiązania:
https://bibliotekanauki.pl/articles/1920851.pdf
Data publikacji:
1992-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
Opis:
The application of the X-ray standing wave (XSW) technique in the case of imperfect crystals meets serious theoretical and interpretational problems. However, well-known advantages of the XSW technique make it especially interesting to the study of the ordering of impurities and of various processes leading to changes in this ordering in various likes of imperfect crystals. In this work we try to answer the question how imperfection of a crystal may influence the changes in fluorescence yield during the XSW measurement. Two likes of imperfect crystals are studied: Si(111) implanted with high energetic Bi$\text{}^{+}$ ions, and Zn$\text{}_{1-x}$Co$\text{}_{x}$Se single crystal with natural (111) face. The discussion of obtained results shows that general features of the X-ray standing wave field are conserved despite the considerable imperfections of the crystals. The results seem to support the applicability of the XSW technique to the study of imperfect materials, although some further theoretical effort would be required.
Źródło:
Acta Physica Polonica A; 1992, 82, 1; 163-171
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
How to Distinguish Perfect Quasi-Crystals from Twins and Other Structures Using Diffraction Experiments?
Autorzy:
Wolny, J.
Powiązania:
https://bibliotekanauki.pl/articles/1920856.pdf
Data publikacji:
1992-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
Opis:
Performing diffraction experiments for various lengths of coherent scattering and using the scaling of peak intensities on a number of atoms one can experimentally distinguish quasi-crystals from the other structures (e.g. twins or random). For perfect quasi-crystals peak intensities scale as N$\text{}^{2}$, for other structures this scaling depends on concentration of atoms, behaving critical for Penrose concentration.
Źródło:
Acta Physica Polonica A; 1992, 82, 1; 173-177
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
X-ray Standing Waves and Rutherford backscattering Studies of the Structure of Si Single Crystals Implanted with Fe Ions
Autorzy:
Vartanyantz, I. A.
Auleytner, J.
Nowicki, L.
Kwiatkowski, S.
Turos, A.
Powiązania:
https://bibliotekanauki.pl/articles/1945411.pdf
Data publikacji:
1996-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
Opis:
The X-ray standing wave and Rutherford backscattering spectroscopy in channelling geometry were applied for the investigation of the structure of silicon single crystals implanted with 80 keV Fe ions. Both methods were used for the determination of crystal damage and lattice location of implanted metal atoms before and after thermal annealing. Both methods gave consistent results regarding the amorphization of Si due to the Fe-ion implantation. Moreover, using both methods some Fe substitution fraction was determined. The depth profiles of implanted atoms were compared to the results of computer simulations. Complementary use of X-ray standing wave and Rutherford backscattering spectroscopy channelling techniques for studies of radiation damage and lattice location of implanted atoms is discussed.
Źródło:
Acta Physica Polonica A; 1996, 89, 5-6; 625-633
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of Morphology and Chemical Composition of Self-Organized Semiconductor Quantum Dots and Wires by X-Ray Scattering
Autorzy:
Holý, V.
Meduňa, M.
Stangl, J.
Roch, T.
Bauer, G.
Powiązania:
https://bibliotekanauki.pl/articles/2030767.pdf
Data publikacji:
2002-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.10.Dp
Opis:
X-ray scattering methods suitable for the investigation of the morphology and chemical composition of self-organized quantum dots and quantum wires are reviewed. Their application is demonstrated in experimental examples showing that a combination of small angle X-ray scattering with high-resolution X-ray diffraction can reveal both the shape and the chemical composition of the self-organized objects.
Źródło:
Acta Physica Polonica A; 2002, 102, 1; 7-19
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of Third Generation Synchrotron Source to Studies of Non-Crystalline Materials: In-Se Amorphous Films
Autorzy:
Burian, A.
Jabłońska, A.
Burian, A. M.
Le Bolloc'h, D.
Metzger, H.
Proux, O.
Hazemann, J. L.
Mosset, A.
Raoux, D.
Powiązania:
https://bibliotekanauki.pl/articles/2030649.pdf
Data publikacji:
2002-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.43.Dq
Opis:
The local structure of vacuum evaporated In-Se amorphous films, containing 50, 60, and 66 at.% Se, was studied using differential anomalous X-ray scattering and extended X-ray absorption fine structure. Both intensity and absorption spectra were measured in the vicinity of the absorption K-edge of Se. The differential anomalous X-ray scattering data were converted to real space by the inverse Fourier transform yielding the differential radial distribution functions. The obtained results provide evidence for the presence of Se-In spatial correlations for In$\text{}_{50}$Se$\text{}_{50}$ and Se-In and Se-Se correlations for In$\text{}_{40}$Se$\text{}_{60}$ and In$\text{}_{34}$Se$\text{}_{66}$ within the first coordination sphere.
Źródło:
Acta Physica Polonica A; 2002, 101, 5; 701-708
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lattice Deformation in Al$\text{}_{x}$Ga$\text{}_{1-x}$As Epitaxial Layers Caused by Implantation with High Doses of 1 Mev Si Ions
Autorzy:
Wieteska, K.
Wierzchowski, W.
Graeff, W.
Turos, A.
Grötzschel, R.
Powiązania:
https://bibliotekanauki.pl/articles/2011027.pdf
Data publikacji:
1999-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.80.-x
Opis:
A series of highly perfect Al$\text{}_{0.45}$Ga$\text{}_{0.55}$ As epitaxial layers implanted with 1 MeV Si ions to the doses in a range 7×10$\text{}^{13}$-2×10$\text{}^{15}$ ions/cm$\text{}^{2}$ were studied with various conventional and synchrotron X-ray diffraction methods. The presently used methods allowed both the measurement of lattice parameter changes and strain induced deformation. The evaluation of complete strain profiles was also performed by numerical simulation of diffraction curves. It was found that the implantation induced considerable change of lattice parameter reached the maximum at the dose 3×10$\text{}^{14}$ ions/cm$\text{}^{2}$. The recorded curves proved also that the lattice parameter is almost constant in the near surface region of the implanted layers. The applied doses did not cause lattice amorphisation at room temperature.
Źródło:
Acta Physica Polonica A; 1999, 96, 2; 289-293
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Interference Fringes in Synchrotron Section Topography of Implanted Silicon with a Very Large Ion Range
Autorzy:
Wieteska, K.
Wierzchowski, W.
Graeff, W.
Dłużewska, K.
Powiązania:
https://bibliotekanauki.pl/articles/1964180.pdf
Data publikacji:
1997-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.80.-x
Opis:
Silicon crystals implanted with 9 MeV protons to the dose of 5×10$\text{}^{17}$ cm$\text{}^{-2}$ were studied with X-ray topographic methods using both conventional and synchrotron radiation sources. After the implantation the crystals were thermally and electron annealed. The implantation produced large 600 μm thick shot-through layer while the total thickness of the samples was 1.6 mm. It was confirmed by means of double crystal topography that the whole crystal was elastically bent. The transmission section patterns revealed both parts of the implanted crystal separated by strong contrasts coming from the most damaged layer and distinct interference fringes which appeared on one side of the topograph only. The location of the fringes changed when the beam entered the other side of the sample. The mechanism of fringe formation was studied with numerical integration of the Takagi-Taupin equations, especially studying the intensity distribution in the diffraction plane. The simulations reproduced the location of the fringes in different geometries and indicate that they can be caused both by variable crystal curvature and variable ion dose.
Źródło:
Acta Physica Polonica A; 1997, 91, 5; 1021-1024
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Observation of Interference Fringes in Bragg-Case Synchrotron Double-Crystal Images of Stacking Faults in Diamond
Autorzy:
Wierzchowski, W.
Moore, M.
Powiązania:
https://bibliotekanauki.pl/articles/1920862.pdf
Data publikacji:
1992-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.70.-r
Opis:
Bragg-case synchrotron double-crystal images of stacking faults were studied in a slab prepared from a synthetic diamond of a good quality. The images of stacking faults in topographs taken on the tails of the rocking curve exhibited well pronounced interference fringes. The fringes were strongly dependent on the angular setting and they were less spaced further from the maximum. The experimental images were compared with those theoretically predicted from an application of plane-wave dynamical theory. A reasonably good correspondence between theoretical and experimental images was obtained. The theoretical images of stacking faults were dependent on the type of stacking fault, producing some difference in the first fringe.
Źródło:
Acta Physica Polonica A; 1992, 82, 2; 185-191
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Images of Dislocations in Synchrotron Bragg-Case Section Topography of Diamond
Autorzy:
Wierzchowski, W.
Moore, M.
Powiązania:
https://bibliotekanauki.pl/articles/1920864.pdf
Data publikacji:
1992-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.70.-r
Opis:
Bragg-case synchrotron section topographs were studied in parallel slabs cut from a synthetic diamond of a good quality. The topographs revealed the Pendellösung fringes and images of dislocations and other defects containing several fringe systems. The experiment provided the opportunity for studying of the theoretical dislocation images obtained by numerical integration of the Takagi-Taupin equations. A program employing a variable step of integration in the Bragg-case has been presented. The influence of the finite slit width and of the limited beam divergence on the theoretical images is also discussed.
Źródło:
Acta Physica Polonica A; 1992, 82, 2; 193-200
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
X-ray Standing Wave Studies of Si (111) Crystal Implanted by Fe and Ni Ions
Autorzy:
Vartanjantz, I.A.
Kovalchuk, M.V.
Sosphenov, A.N.
Auleytner, J.
Majewski, J.
Powiązania:
https://bibliotekanauki.pl/articles/1891973.pdf
Data publikacji:
1991-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.70.Sk
Opis:
The X-Ray Standing Wave Method (XRSW) was applied for the investigation of the silicon samples implanted with 80 keV Fe and Ni ions. The samples were measured by the XRSW method before and after annealing process. For theoretical calculations the two layer model was used. The analysis revealed that after annealing only a slight amount (~20÷30%) of the implanted atoms occupy the position of the Si crystal planes. The Rutherford backscattering (RBS) experiment that confirms the results obtained by the XRSW method was performed.
Źródło:
Acta Physica Polonica A; 1991, 80, 6; 811-817
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lattice Deformation Studies in Silicon Implanted with High-Energy Protons
Autorzy:
Wieteska, K.
Dłużewska, K.
Wierzchowski, W.
Powiązania:
https://bibliotekanauki.pl/articles/1945258.pdf
Data publikacji:
1996-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.80.-x
Opis:
The deformation of crystal lattice in silicon implanted with protons of energy 1.6-9 MeV was studied by means of X-ray topography and double-crystal rocking curve measurements. The samples were investigated as-implanted and after thermal and electron annealing. The surface relief of the implanted part of the crystal was also revealed with optical methods. As-implanted wafers exhibited spherical bending being convex at the implanted side. Thermal and electron annealing caused a dramatic increase in bending of the implanted part while the bending of the remaining part of the sample was reduced. A characteristic behaviour of a double-crystal topographic contrast in the annealed crystals was explained due to bending of the shot-through layer along the Gaussian profile.
Źródło:
Acta Physica Polonica A; 1996, 89, 3; 395-400
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Curved Surfaces in Disordered Carbons by High Energy X-ray Scattering
Autorzy:
Burian, A.
Szczygielska, A.
Kołoczek, J.
Dore, J.
Honkimaki, V.
Duber, S.
Powiązania:
https://bibliotekanauki.pl/articles/2030692.pdf
Data publikacji:
2002-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.10.Eq
61.46.+w
Opis:
Disordered carbons prepared by slow pyrolysis of saccharose and anthracene and subsequent heat treatment at 1000ºC and 2300ºC have been studied by high energy X-ray diffraction. Computer simulations of the powder diffraction patterns of fullerenes, nanotubes and carbon models have been compared with the experimental data after conversion to real space via the Fourier transform. The presence of fullerene- and nanotube-like fragments with non-six membered rings in the investigated samples has been deduced by detailed analysis of the radial distribution functions of the saccharose- and anthracene-based carbons and related to resistance to graphitization of the saccharose-based carbons and to stability of the growing crystallites in the case of the anthracene-based carbons. The obtained results are compared to high resolution electron microscopy and Raman studies.
Źródło:
Acta Physica Polonica A; 2002, 101, 5; 751-759
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of Near Surface Distortions in Si Single Crystals by Means of Spatial Distribution Analysis of Reflected Beams
Autorzy:
Khrupa, V. I.
Krasulya, S. M.
Machulin, V.
Datsenko, L. I.
Auleytner, J.
Powiązania:
https://bibliotekanauki.pl/articles/1945216.pdf
Data publikacji:
1996-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.40.-z
61.10.-i
Opis:
A diffractometrical method for quantitative evaluation of structure perfection level in silicon single crystals containing various types of near surface distortions is described. The method is based on the spatial distribution analysis of the reflected intensity in the Bragg case of diffraction. To implement the proposed approach one has to satisfy the condition of the so-called low X-ray absorption because in this case the penetration depth of diffracted radiation exceeds the corresponding value of extinction length. It permits us to obtain a remarkable value of noncoherent reflectivity due to defects placed in deep (on the extension of absorption length) regions of a crystal and therefore, to increase the sensitivity of scattering for low distortions of crystal lattice. Using the method described here the extension of various disturbed layers as well as the level of the static Debye-Waller factor of a crystal can be determined. The effect of surface distortions caused by mechanical treatment and the influence of the following thermal annealing as well as irradiation by high energy protons on the defective structure of the samples were investigated.
Źródło:
Acta Physica Polonica A; 1996, 89, 3; 309-313
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Interpretation of Differential Anomalous X-Ray Scattering Data for Amorphous Cd-As
Autorzy:
Burian, A.
Lecante, P.
Mosset, A.
Galy, J.
Tonnerre, J. M.
Raoux, D.
Powiązania:
https://bibliotekanauki.pl/articles/1931688.pdf
Data publikacji:
1994-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.70.Dm
61.10.-i
Opis:
The computational procedure, based on Warren's exact method for an amorphous sample with more than one atom, was developed to obtain the short-range order structural parameters from the differential anomalous X-ray scattering data, collected using the synchrotron radiation. The experimental differential radial distribution functions were fitted with the true distribution functions expressed in an analytical form and broadened by convolution with the pair functions. It was found that atoms in the amorphous Cd-As films remain almost tetrahedrally coordinated and the investigated alloys are chemically ordered.
Źródło:
Acta Physica Polonica A; 1994, 86, 4; 633-640
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Process of Amorphization Induced by Mechanical Alloying of Iron with Tungsten and Niobium
Autorzy:
Jartych, E.
Oleszak, D.
Żurawicz, J.
Powiązania:
https://bibliotekanauki.pl/articles/2028976.pdf
Data publikacji:
2001-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
76.80.+y
61.10.-i
Opis:
Mechanical alloying method was used to synthesise powders of iron with tungsten and niobium. Mössbauer spectroscopy and X-ray diffraction have been applied to monitor the progress in solid-state reactions. In the case of Fe-W system, exhibiting a positive heat of mixing, no trace of amorphization was observed for 20 and 33 at.% of W, as the calculations of phase diagram (CALPHAD) method suggest. During the mechanical alloying process, two solid solutions Fe(W) and W(Fe) were obtained. Mössbauer measurements allowed to recognise the Fe(W) solid solution as a ferromagnetic phase, while the W(Fe) solid solution as a paramagnetic one. In the case of Fe-Nb system, exhibiting a negative heat of mixing, single phase amorphous alloys were synthesised during mechanical alloying of iron with 48 and 64 at.% of Nb. For both investigated compositions, the final products of mechanical alloying processes were amorphous paramagnetic alloys.
Źródło:
Acta Physica Polonica A; 2001, 100, 5; 731-736
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structural Characterization of Carane Derivative Stereoisomers - Potent Local Anesthetics
Autorzy:
Grochowski, J.
Serda, P.
Pasenkiewicz-Gierula, M.
Czarnecki, R.
Librowski, T.
Lochyński, S.
Frąckowiak, B.
Powiązania:
https://bibliotekanauki.pl/articles/2030630.pdf
Data publikacji:
2002-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
82.30.Qt
61.10.-i
Opis:
The paper reports on structural investigation and phase analysis of a newly synthesized potent local anesthetic with chiral molecular structure. Absolute structure and absolute configuration on four chiral centres was determined using microcrystalline single-crystal diffraction with anomalous scattering of X-ray radiation azimuthal scan technique. Phase analysis for new compound (KP23SS) and its epimer (KP23RS) was carried out using classical and synchrotron radiation powder diffraction. Enantiopurity of the bulk material was verified for both isomers by comparison of experimental and simulated high-resolution powder diffraction diagrams. The presence of two new polymorphic phases of KP23RS was documented. Comparative conformational analysis was carried out using differential Fourier synthesis and least-squares molecule overlap technique. A model of epimeric disorder was discussed for the homochiral phase.
Źródło:
Acta Physica Polonica A; 2002, 101, 5; 665-674
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Single-Crystal X-Ray Diffractometry Using Synchrotron Radiation
Autorzy:
Eichhorn, K. D.
Powiązania:
https://bibliotekanauki.pl/articles/1920826.pdf
Data publikacji:
1992-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
07.85.+n
61.10.-i
Opis:
The properties of synchrotron radiation relevant to single-crystal X-ray diffractometry are: its high intensity over a wide spectral range, a small source size and a low divergence in the 0.1 mrad range, about 90% linear polarization in the horizontal plane, a pulsed time structure, and a time dependent intensity. The latter property requires monitoring of the primary beam intensity and its polarization state which slightly complicates data collection and needs particular attention in the data reduction stage. The other properties of synchrotron radiation, however, extend the range of X-ray diffractometry to experiments which are not feasable with sealed X-ray tubes. The high source intensity makes data collection possible on crystals down to and below 10 μm diameter. Measurement of weak and very weak ("forbidden") reflections profits from high intensity, low divergence, and a good peak-to-background ratio. Data collection at short wavelengths is useful to decrease both absorption and extinction effects and provides the resolution required for high precision structure analysis. Wavelength tun-ability is frequently used to exploit resonant X-ray scattering ("anomalous dispersion") for structure research. Examples are determination of absolute configuration, contrast variation, and phase determination from both single-and multiple-wavelength measurements ("MAD-phasing"). X-ray dichroism and double refraction are observed in the vicinity of absorption edges, causing an anisotropy and polarization dependence of anomalous scattering. This anisotropy may give rise to a violation of extinction rules for glide-planes and screw-axes, with orientation- and polarization-dependent intensities. More recently, these affects have been successfully used to derive (partial) phase information. Other applications are magnetic X-ray scattering and time-resolved X-ray diffraction, the latter exploiting the time structure of the synchrotron radiation source.
Źródło:
Acta Physica Polonica A; 1992, 82, 1; 51-65
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Radial Distribution Function Analysis of Carbon Nanotubes
Autorzy:
Szczygielska, A.
Jabłońska, A.
Burian, A.
Dore, J. C.
Honkimaki, V.
Nagy, J. B.
Powiązania:
https://bibliotekanauki.pl/articles/2014446.pdf
Data publikacji:
2000-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
81.05.Tp
Opis:
Wide-angle X-ray scattering studies of carbon nanotubes produced by catalytic decomposition of acetylene on a supported Co catalyst are reported. The X-ray intensities were recorded up to maximum scattering vector K$\text{}_{max}$=24Å and then Fourier transformed to real space. Yielding the radial distribution functions of good spatial resolution were analysed by the model based on fitting procedures method. Detailed analysis of the experimental data by a least-squares fitting procedure shows that the local atomic structure exhibits the expected hexagonal network with the nearest-neighbour C-C distance of 1.41Å. Investigation of stacking nature of subsequent layers suggests the structure in which adjacent layers are arranged without spatial correlations with inter-tubule spacing of about 3.4Å.
Źródło:
Acta Physica Polonica A; 2000, 98, 5; 611-617
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Integral Structure Perfection Diagnostics of Single Crystals Using Two Wavelengths of X-Ray Spectrum
Autorzy:
Datsenko, L.
Krasulya, S.
Machulin, V.
Auleytner, J.
Khrupa, V.
Powiązania:
https://bibliotekanauki.pl/articles/1964123.pdf
Data publikacji:
1997-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.40.-z
61.10.-i
Opis:
A new approach to determination of microdefect structure parameters by means of single crystal diffractometer is proposed. The approach is based on the measurements of the integral reflectivity of a sample for two selected X-ray wavelengths providing with the approximations of thin and thick crystal, respectively.
Źródło:
Acta Physica Polonica A; 1997, 91, 5; 935-938
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Uniaxial Stretching on Structural Properties of Poly(3-Alkylthiophenes)
Autorzy:
Łużny, W.
Zagórska, M.
Powiązania:
https://bibliotekanauki.pl/articles/1964842.pdf
Data publikacji:
1997-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
36.20.-r
61.10.-i
Opis:
The influence of uniaxial stretching on the molecular structure of poly(3-alkylthiophenes) was studied with the use of X-ray diffraction. Three poly(3-alkylthiophenes), namely these containing n-hexyl, n-octyl and n-decyl groups, were investigated. The samples were oriented by stretching and the diffraction patterns for two geometries of scattering were obtained for undoped samples. The comparison of experimental diffraction data for unoriented and oriented samples, gives information about the role of the side chains in the changes of molecular conformation induced by stretching of the polymer sample. The main conclusion of our work is that the process of orientation induces similar phenomena in all samples studied, but the structural and conformation changes depend on the side chain length: the shorter the alkyl substituent, the easier the straightening of the main polymer chain. The authors suggest that uniaxial stretching of poly(3-alkylthiophenes) changes the degree of main chain planarity. This effect can influence the π-conjugation in polymer system, which may have great importance for any future application of poly(3-alkylthiophenes).
Źródło:
Acta Physica Polonica A; 1997, 92, 3; 491-500
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
X-Ray and Electron-Optical Characterization of ZnSe(Co) Crystal with Natural Face
Autorzy:
Auleytner, J.
Domagała, J.
Gołacki, Z.
Pawłowska, M.
Pełka, J.
Regiński, K.
Powiązania:
https://bibliotekanauki.pl/articles/1929340.pdf
Data publikacji:
1993-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.14.Hg
61.16.Bg
Opis:
Using complementary X-ray and electron-optical methods, a ZnSe(Co) crystal with natural face was investigated. X-ray diffraction methods such as double-crystal X-ray reflection topography, double-crystal diffractometry for rocking curve measurements, precise lattice constant measurements by the Bond technique were used for crystal structure characterization and X-ray fluorescence method for studies of chemical composition along the crystal. The scanning electron microscopic image of the crystal surface and reflection diffraction of the high-energy electrons enriched the crystal structure characterization. It was shown that X-ray characterization and reflection high-energy electron diffraction can be regarded as very important complementary tools for non-destructive investigation of the ZnSe(Co) crystal surface layers.
Źródło:
Acta Physica Polonica A; 1993, 83, 6; 759-768
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Influence of Laser Irradiation Time on Fe-Si-C System Structure
Autorzy:
Amulevicius, A.
Daugvila, A.
Davidonis, R.
Mazeika, K.
Powiązania:
https://bibliotekanauki.pl/articles/2037036.pdf
Data publikacji:
2003-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.18.Fs
61.10.-i
61.80.Ba
Opis:
The influence of different laser irradiation times on the structure of grey cast iron was studied. Mössbauer spectroscopy and X-ray diffraction were used to characterise the changes caused by laser irradiation. The composition of martensite and austenite as well as the creation of carbide phases during quenching were studied. Modelling of temperature during laser irradiation allowed differences in the influence of different laser irradiation types and times to be explained.
Źródło:
Acta Physica Polonica A; 2003, 104, 6; 537-548
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structure Changes in Cz-Si Single Crystals Irradiated with Fast Oxygen and Neon Ions
Autorzy:
Datsenko, L.
Żymierska, D.
Auleytner, J.
Klinger, D.
Machulin, V.
Klad'ko, V.
Melnik, V.
Prokopenko, I.
Czosnyka, T.
Choiński, J.
Powiązania:
https://bibliotekanauki.pl/articles/2011007.pdf
Data publikacji:
1999-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.80.Jh
61.10.-i
61.72.-y
Opis:
The research of the surface and the near-surface region of Cz-Si wafers irradiated with fast oxygen and neon ions of energy 4 MeV/u and dose 10$\text{}^{14}$ particles/cm$\text{}^{2}$ is presented. In our study several methods based on the Bragg case of X-ray diffraction using Ag K_{α$\text{}_{1}}$, as well as reflection high-energy electron diffraction and Nomarsky optical microscopy were used. It was shown that implantation with fast neon ions causes larger disturbances of silicon crystal structure than irradiation with oxygen ions.
Źródło:
Acta Physica Polonica A; 1999, 96, 1; 137-142
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structural Studies of Carbon Nanotubes and Related Materials by Neutron and X-Ray Diffraction
Autorzy:
Dore, J.
Burian, A.
Tomita, S.
Powiązania:
https://bibliotekanauki.pl/articles/2014376.pdf
Data publikacji:
2000-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.46.+w
61.12.-q
61.10.-i
Opis:
X-ray and neutron diffraction measurements are presented for a number of carbon samples prepared by different techniques. The information obtained from diffraction studies is presented in relation to other types of investigation, particularly in relation to electron microscopy. The characteristics of the graphene sheets are discussed in relation to these features.
Źródło:
Acta Physica Polonica A; 2000, 98, 5; 495-504
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Studies of Be-Fe Compounds Synthesized by Laser Irradiation
Autorzy:
Amulevicius, A.
Mazeika, K.
Sipavicius, C.
Baltusnikas, A.
Powiązania:
https://bibliotekanauki.pl/articles/2043662.pdf
Data publikacji:
2005-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.18.Fs
61.10.-i
61.80.Ba
Opis:
The FeBe$\text{}_{2,5,11}$ compounds and theα-Fe(Be) solid solution of Be$\text{}_{x}$Fe$\text{}_{1-x}$ system were synthesized by laser irradiation from a powder mixture. The dependence of the phase structure on the initial sample composition (x=0.1-0.95) was studied. The phases were determined and studied by means of Mössbauer spectroscopy and X-ray diffraction.
Źródło:
Acta Physica Polonica A; 2005, 108, 3; 467-478
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
First X-Ray Evidence of Heterogeneous Impurity Correlations in Very Highly Doped n-GaAs
Autorzy:
Słupiński, T.
Zielińska-Rohozińska, E.
Powiązania:
https://bibliotekanauki.pl/articles/1968417.pdf
Data publikacji:
1997-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.72.-y
71.55.-i
61.10.-i
Opis:
Measurements of X-ray scattering from very highly doped GaAs:Te single crystals as a function of doping level and thermal treatment (annealing temperature) are reported. Reversible diffuse X-ray scattering occurs after sample annealing below a certain temperature. Presented results indicate an inhomogeneous arising of impurity-impurity correlations in GaAs:Te solid solution. Observed features of diffuse X-ray scattering in reciprocal space can be well understood within Krivoglaz theory of scattering due to spatial fluctuations of solute atoms pair correlation function and related lattice deformations. Good coincidence of diffuse X-ray scattering with the free electron concentration changes caused by an annealing is reported. Free electron concentration drop accompanying impurity correlation strongly suggests a certain form of impurity bonding.
Źródło:
Acta Physica Polonica A; 1997, 92, 5; 971-975
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Does Carbon Prefer Flat or Curved Surfaces?
Autorzy:
Burian, A.
Dore, J. C.
Powiązania:
https://bibliotekanauki.pl/articles/2014367.pdf
Data publikacji:
2000-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.48.+c
61.10.-i
78.30.Na
Opis:
The presence of fullerene- and nanotube-like elements in carbons prepared from saccharose and anthracene by slow pyrolysis and then heat treated at 1000°C, 1900°C, and 2300°C has been revealed using Raman spectroscopy. High energy X-ray diffraction has been used to examine the effect on these carbons of heat treatment. Tendency to graphitization of the anthracene-based carbon and resistance to graphitization of the saccharose carbon will be considered in the light of the formation of curved graphitic networks and cages. The obtained results lead us to propose a model of the structure of non-graphitizing and graphitizing carbons.
Źródło:
Acta Physica Polonica A; 2000, 98, 5; 457-468
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Defect Structure of Pressure Treated Czochralski Grown Silicon Investigated by X-Ray Topography and Diffractometry
Autorzy:
Misiuk, A.
Härtwig, J.
Prieur, E.
Ohler, M.
Bąk-Misiuk, J.
Domagała, J.
Surma, B.
Powiązania:
https://bibliotekanauki.pl/articles/1964154.pdf
Data publikacji:
1997-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.72.Yx
81.40.Vw
61.10.-i
Opis:
The defect structure of Czochralski grown silicon single crystals annealed at 870-1400 K under hydrostatic pressure up to 1 GPa was investigated by conventional and synchrotron radiation X-ray topography and by reciprocal space mapping. Hydrostatic pressure promotes oxygen precipitation from oversaturated Si-O solid solution and the creation of structural defects.
Źródło:
Acta Physica Polonica A; 1997, 91, 5; 987-991
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Data Processing Programs for Analysis of Diffraction Images of Macromolecular Crystals Recorded using Synchrotron Radiation
Autorzy:
Gilski, M.
Powiązania:
https://bibliotekanauki.pl/articles/1431531.pdf
Data publikacji:
2012-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
07.85.Qe
61.05.cp
Opis:
Besides the crystal preparation, the first and crucial step in the process of protein structure determination is proper processing of the collected diffraction images, as they provide the experimental observations used throughout the entire process of structure solution and refinement. In the last two decades several computer programs have been developed. Among the most used and popular are: HKL2000, MOSFLM, d*TREK and XDS package. To find out the advantages and disadvantages of the data processing programs, several very different data sets, including diffraction data from DNA/RNA and protein crystals were tested. It has been found that all the major programs for processing and analysis of diffraction data give excellent and comparable results with good quality, medium resolution data sets, but their treatment of very high resolution or imperfect data differs in terms of indexing, spot integration, scaling and the treatment of errors. If the diffraction data are of good quality and the problem is relatively straightforward, the automated approach to data processing may be most appropriate. On the other hand, if one is trying to squeeze out as much information from the experimental data as possible, then only expert manual processing can be successful, regardless of the data quality.
Źródło:
Acta Physica Polonica A; 2012, 121, 4; 871-875
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
X-Ray and Electron-Optical Characterization of ZnTe/CdTe and ZnTe/GaAs Epitaxial Layers Obtained by the MBE Method
Autorzy:
Auleytner, J.
Dziuba, Z.
Górecka, J.
Pełka, J.
Regiński, K.
Powiązania:
https://bibliotekanauki.pl/articles/1931657.pdf
Data publikacji:
1994-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.14.Hg
61.10.-i
68.55.-a
Opis:
X-ray diffraction topography (Bragg diffraction) and X-ray rocking curve measurements were used to study the perfection and structural properties of ZnTe epitaxial layers on the CdTe and GaAs substrates. ZnTe epitaxial layers on CdTe were grown by MBE method by using a machine made in the Institute of Physics of the Polish Academy of Sciences. The ZnTe layers on GaAs were produced on the other, factory-made MBE system. The comparison between the X-ray topographical images of the substrate and epitaxial layer shows that imperfections on the substrate surface cause imperfections in the epitaxial layer. The results of double-crystal diffractometry measurements show that the perfection of the layer on the GaAs substrate is higher than that on the CdTe. The presence of microtwining in the ZnTe layer on the CdTe substrate was confirmed by RHEED measurements. The X-ray standing wave fluorescent spectra were also measured for the samples.
Źródło:
Acta Physica Polonica A; 1994, 86, 4; 567-574
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Oxygen Precipitation in Si:O Annealed under High Hydrostatic Pressure
Autorzy:
Misiuk, A.
Bąk-Misiuk, J.
Bryja, L.
Kątcki, J.
Ratajczak, J.
Jun, J.
Surma, B.
Powiązania:
https://bibliotekanauki.pl/articles/2030659.pdf
Data publikacji:
2002-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.72.Yx
81.40.Vw
Opis:
Effect of hydrostatic pressure up to 1.2 GPa on oxygen-implanted silicon, Si:O (O$\text{}^{+}$ dose, D, within the 6×10$\text{}^{17}$-2×10$\text{}^{18}$ cm$\text{}^{-2}$ range), treated at 1230-1570 K, was investigated by X-ray, transmission electron microscopy and photoluminescence methods. The pressure treatment affects oxygen precipitation and defect creation, especially in low oxygen dose implanted Si:O (D=6×10$\text{}^{17}$ cm$\text{}^{-2}$). Such investigation helps in understanding the stress related phenomena in Si wafers with buried insulating layer.
Źródło:
Acta Physica Polonica A; 2002, 101, 5; 719-727
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of Bond Valence Model to Stability of RE Oxycompounds
Autorzy:
Hölsä, J.
Koski, K.
Lamminmäki, R.-J.
Rahiala, H.
Säilynoja, E.
Powiązania:
https://bibliotekanauki.pl/articles/1963262.pdf
Data publikacji:
1997-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.40.-z
61.66.-f
61.10.-i
Opis:
The bond valence model was used to study the stability of the non-stoichiometric $LaO_{1-x}F_{1+2x}$ phases, the solid solubility in the ($La_{1-x}Gd_{x}$) OCl system and the phase transformation in the REOCl ($RE^{3+}=La^{3+} -Nd^{3+}, Sm^{3+}-Gd^{3+}, Ho^{3+}, and Y^{3+}$) series. The stability of the non-stoichiometric $LaO_{1-x}F_{1+2x}$ (0 ≤ x ≤ 0.3) phase decreases with increasing excess fluoride. The global instability index values close to 0.2 indicate the instability of the non-stoichiometric phase. The relative stability of the ($La_{1-x}Gd_{x}$)OCl (0 ≤ x ≤ 1.0) solid solutions achieved its minimum in the middle of the series. However, the X-ray powder diffraction results indicated complete solid solubility in the whole ($La_{1-x}Gd_{x}$)OCl series and no phase separation was observed. The bond valence model was used to explain the structural transformation from the tetragonal oxychlorides, REOCl (RE = La-Er, and Y), to hexagonal beyond ErOCl. The calculated global instability index values did not show any clear trend across the REOCl series probably due to the inaccuracies and incoherencies in the original structural data.
Źródło:
Acta Physica Polonica A; 1997, 91, 3; 563-568
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
High Resolution X-ray Reciprocal Space Mapping
Autorzy:
Bauer, G.
Li, J. H.
Holy, V.
Powiązania:
https://bibliotekanauki.pl/articles/1943985.pdf
Data publikacji:
1996-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
68.55.-a
61.72.Lk
Opis:
A survey will be given on recent advances in the investigation of semiconductor epilayers, heterostructures and superlattices using reciprocal space mapping techniques based on triple-axis diffractometry. It is shown that X-ray reciprocal space mapping yields quantitative information on strain, strain relaxation, as well as composition in such structures. These data are obtained from analyses of the isointensity contours of scattered X-ray intensity around reciprocal lattice points. Further analysis of the diffuse scattering yields also information on defect distribution in the epilayers.
Źródło:
Acta Physica Polonica A; 1996, 89, 2; 115-127
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structural Properties of MnTe, ZnTe, and ZnMnTe
Autorzy:
Gonzalez Szwacki, N.
Przeździecka, E.
Dynowska, E.
Bogusławski, P.
Kossut, J.
Powiązania:
https://bibliotekanauki.pl/articles/2038244.pdf
Data publikacji:
2004-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.50.Ah
75.50.Pp
61.10.-i
Opis:
Structural properties of ZnTe, MnTe, and Mn$\text{}_{1-x}$Zn$\text{}_{x}$Te alloy with zinc-blende, NiAs, and wurtzite phases were investigated by ab initio calculations. The calculated structural properties are in good agreement with the available experimental data. Theory predicts that the zinc-blende phase is more stable than wurtzite for all compositions. Mn$\text{}_{1-x}$Zn$\text{}_{x}$Te samples with 0.01 < x < 0.20 were grown by MBE. X-ray analysis of their crystalline structure revealed the presence of zinc-blende, wurtzite, and NiAs phases. The dominant phase changes from NiAs for the sample with x=0.01 to wurtzite for x=0.20. The observed stabilization of the wurtzite phase is possibly due to the hexagonal structure of the MnTe buffer.
Źródło:
Acta Physica Polonica A; 2004, 106, 2; 233-238
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Manganese Distribution in CdMnTeSe Crystals. EXAFS Data Analysis
Autorzy:
Kisiel, A.
Łażewski, J.
Zimnal-Starnawska, M.
Burattini, E.
Mycielski, A.
Powiązania:
https://bibliotekanauki.pl/articles/1952538.pdf
Data publikacji:
1996-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.72.Vv
75.50.Pp
Opis:
The extended X-ray absorption fine structure (EXAFS) technique has been used to investigate the first shell coordination in zinc-blende quaternary Cd$\text{}_{1-x}$Mn$\text{}_{x}$Te$\text{}_{1-y}$Se$\text{}_{y}$ (0.0 ≤ x ≤ 0.15; 0.0 ≤ y ≤ 0.20) alloys. The experimental data have been collected with the use of synchrotron radiation. All the nearest-neighbour distances have been found as linearly dependent on Se and Mn concentration. For each composition a consistent deviation from full random distribution of Mn atoms around Se and Te atoms was observed. Possible reasons of preferential Mn-Se over Mn-Te pairing were discussed.
Źródło:
Acta Physica Polonica A; 1996, 90, 5; 1032-1034
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
High Resolution X-Ray Diffraction Investigations of Si/SiGe Quantum Well Structures and Si/Ge Short-Period Superlattices
Autorzy:
Bauer, G.
Koppensteiner, E.
Hamberger, P.
Nützel, J.
Abstreiter, G.
Kibbel, H.
Presting, H.
Kasper, E.
Powiązania:
https://bibliotekanauki.pl/articles/1929613.pdf
Data publikacji:
1993-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
68.65.+g
61.10.-i
68.55.Jk
Opis:
Double crystal and triple axis X-ray diffractometry was used to characterize the structural properties of Si/Si$\text{}_{1-x}$Ge$\text{}_{x}$ multiquantum well samples grown pseudomorphically on Si(001) substrates, as well as of short-period Si$\text{}_{9}$Ge$\text{}_{6}$ superlattices grown by molecular beam epitaxy on rather thick step-graded Si$\text{}_{1-x}$Ge$\text{}_{x}$ (0 < x < 0.4, 650 nm thick) buffers followed by 550 nm Si$\text{}_{0.6}$ Ge$\text{}_{0.4}$ layers. Reciprocal space maps around the (004) and (224) reciprocal lattice points yield direct information on the strain status of the layers in the heterostructure systems and in particular on the amount of strain relaxation.
Źródło:
Acta Physica Polonica A; 1993, 84, 3; 475-489
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Small Angle X-Rays Scattering Studies of Biomolecules
Autorzy:
Funari, S. S.
Powiązania:
https://bibliotekanauki.pl/articles/2030570.pdf
Data publikacji:
2002-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
87.80.-y
64.75.+g
Opis:
The building units of biological systems, the biomolecules, cannot easily be organized or even classified into defined categories. They can be as simple as water or complex as tintin, a muscle protein extremely large with several thousand atoms. To understand their function, one must know their characteristics, where they occur and what they do. One approach to reach such an ambitious task is to determine their structure, as single molecules or assembled into aggregates. Small angle X-ray scattering is the most important method for this purpose. We present studies carried out on several systems, and aiming at different questions about them. We start with lipids, the main components of the cell membranes. These membranes form the cell boundaries, the moiety required for the so-called membrane proteins, but also influence significantly several aspects of biological activity. More complex systems like a muscle fibre is also presented, showing that changes in the structure are related to the movement mechanism. It becomes easy to conclude that knowing the structures and the changes occurring in them is an important way to understand the function of biomolecules and therefore their role in the life cycle.
Źródło:
Acta Physica Polonica A; 2002, 101, 5; 647-658
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Dislocation Interactions with Impurities on their Topographical Images in Silicon Crystals
Autorzy:
Auleytner, J.
Skorokhod, M. Ya.
Datsenko, L. I.
Khrupa, V. I.
Powiązania:
https://bibliotekanauki.pl/articles/1945730.pdf
Data publikacji:
1996-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.72.Cc
61.72.Ff
81.40.Cd
Opis:
Silicon crystals contained copper atoms included by diffusion way during high temperature treatment have been investigated by means of X-ray transmission topography (Lang method). The studies allow us to observe the increase or decrease in the dislocation images widths in dependence on the time of diffusin annealing. In one case, during the more prolonged decoration process a build-up of decorating particles on dislocation occurs with widening of the topographic images of this dislocation. In another case (short time of decorating process) some compensation of defect deformation fields has been noticed (shortening of the mentioned images takes part). The obtained effects depend not only on the type of intrinsic impurities which take part in forming the Cottrell atmospheres but also on the duration of diffusion annealing. The observed results of interaction of dislocations with impurities have been confirmed by the studies of the integral reflectivity of decorated samples by means of the double-crystal spectrometer.
Źródło:
Acta Physica Polonica A; 1996, 90, 3; 541-546
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Combined Analyses of Ion Beam Synthesized Layers in Porous Silicon
Autorzy:
Ramos, A. R.
Pászti, F.
Horváth, Z. E.
Vázsonyi, É.
Conde, O.
da Silva, M. F.
da Silva, M. R.
Soares, J. C.
Powiązania:
https://bibliotekanauki.pl/articles/2028988.pdf
Data publikacji:
2001-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.18.Bn
61.43.Gt
68.55.Ln
Opis:
High dose ion implantation was used to form polycrystalline silicide films on porous silicon with different native concentrations of light impurities (C and O). Porous silicon layers severalμm thick were implanted with 170 keV Cr$\text{}^{+}$ ions to fluences of 3×10$\text{}^{17}$ ions/cm$\text{}^{2}$ both at room temperature and 450ºC. Similar samples were implanted with 100 keV Co$\text{}^{+}$ ions to fluences of 2×10$\text{}^{17}$ ions/cm$\text{}^{2}$ at room temperature, 350ºC, and 450ºC. The formed silicide compounds were studied by Rutherford backscattering spectrometry, elastic recoil detection, glancing incidence X-ray diffraction, and four point-probe sheet resistance measurements. Selected Co implanted samples were analysed by cross-section transmission electron microscopy. Results show that the light impurities were partially expelled from the forming silicide layer. Combining cross-section transmission electron microscopy with ion beam methods it was possible to show that, in the implanted region, the porous structure collapses and densifies during implantation, but the underlying porous silicon remains intact. The layer structure, as well as the quality and type of the formed silicide, were found to depend on the original impurity level, implantation temperature, and annealing.
Źródło:
Acta Physica Polonica A; 2001, 100, 5; 773-780
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Correlation Length in PBnA Liquid Crystal Family
Autorzy:
El Guermai, K.
Ayadi, M.
El Boussiri, K.
Powiązania:
https://bibliotekanauki.pl/articles/1992845.pdf
Data publikacji:
1998-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.30.-v
61.10.-i
64.70.Md
61.30.Gd
Opis:
We present a study of the range molecular interactions inside layers in smectic phases A and I of PBnA (phenyl-4 benzylidene 4'-alkylaniline) liquid crystals family. The purpose of this work is to determine the correlation length of the molecules' gravity centers in existing domain of smectic phases and at the transition between them. We used X-rays in-plane peaks of the pattern diffraction of aligned sample by a magnetic field.
Źródło:
Acta Physica Polonica A; 1998, 94, 5-6; 779-784
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On Some Structural and Spectroscopic Aspects of Rare Earth Oxycompounds
Autorzy:
Hölsä, J.
Säilynoja, E.
Porcher, P.
Powiązania:
https://bibliotekanauki.pl/articles/1952800.pdf
Data publikacji:
1996-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.12.-q
61.50.-f
61.66.Fn
Opis:
The aim of this account is to present the use and the advantages of different experimental and theoretical methods in the study of the structural and spectroscopic properties of rare earth (RE) oxyfluorides. The structural characterization was carried out with the X-ray and neutron powder diffraction techniques combined with the analysis of the acquired data with the Rietveld profile refinement method. The detailed spectroscopic studies were also used by employing the optical absorption and luminescence as well as inelastic neutron scattering data. Simple spectroscopic measurements gave, however, only qualitative description of the spectroscopic properties studied. More sophisticated and quantitative means was obtained by the application of the phenomenological crystal field theory to the spectroscopic data. On the other hand, the structural data was also used as initial input to electrostatic point charge calculation in order to extract the spectroscopic information. The structural and spectroscopic studies comprised the verification of the exact crystal and energy level structures and the characterization of the different interactions modifying the spectroscopic properties of the RE$\text{}^{3+}$ ions. Finally, the results from the theoretical model were used to explain the evolution of the crystal field effect on the 4f$\text{}^{N}$ energy level structure of the RE$\text{}^{3+}$ ion in the RE oxyfluorides series.
Źródło:
Acta Physica Polonica A; 1996, 90, 6; 1193-1201
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
X-ray Holography with a Position Sensitive Detector
Autorzy:
Lausi, A.
Kopecky, M.
Busetto, E.
Savoia, A.
Powiązania:
https://bibliotekanauki.pl/articles/2030559.pdf
Data publikacji:
2002-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
07.85.-m
42.40.-i
Opis:
Integrating photon collection on position sensitive detectors used in combination with an absorption filter offers many advantages in X-ray fluorescence holography experiments: (i) the simultaneous recording of the full hologram allows us to overcome most of the difficulties - notably the large number of experimental points and the precision requirements - that make the practical realization of the measurement of holographic patterns very difficult and time demanding also when using powerful synchrotron radiation sources; (ii) the high angular resolution and the very precise detection of intensities make the reconstruction of images of distant as well as light atoms possible; (iii) area detectors are readily available at most crystallography dedicated beamlines at synchrotron radiation sources, so there is no need of complex, dedicated instrumentation. As an example, the hologram of a CoO single crystal recorded on an imaging plate is reported, evidencing the images of atoms located up to more than 7Å far from the emitter and also of the light oxygen atoms.
Źródło:
Acta Physica Polonica A; 2002, 101, 5; 621-628
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Time-Resolved X-Ray Diffraction Studies on Biological Systems
Autorzy:
Rapp, G.
Powiązania:
https://bibliotekanauki.pl/articles/1920834.pdf
Data publikacji:
1992-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
87.80.+s
52.50.Jm
Opis:
Understanding of biological function requires knowledge both on structural and dynamical aspects. The aim of time-resolved X-ray diffraction is to combine structural and kinetic methods by monitoring structural or conformational changes within a single protein or assemblies of proteins during their biological action in real time. This requires (i) a powerful X-ray source, (ii) appropriate detectors capable of dealing with high local and total count rates and (iii) a suitable trigger mechanism. These aspects are briefly discussed with emphasis on light as trigger for initiation of structural or conformational changes. Examples are presented on muscle contraction, lipid phase transitions, the photocycle of bacteriorhodopsin and the application of Laue crystallography on the protein p21.
Źródło:
Acta Physica Polonica A; 1992, 82, 1; 103-120
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fine Diffraction Effects in Si Single Crystals Implanted with Fast Ar Ions and Annealed
Autorzy:
Żymierska, D.
Godwod, K.
Adamczewska, J.
Auleytner, J.
Choiński, J.
Regiński, K.
Powiązania:
https://bibliotekanauki.pl/articles/2030690.pdf
Data publikacji:
2002-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.80.Jh
61.80.-x
61.10.-i
85.40.Ry
Opis:
The paper presents high-resolution X-ray diffraction studies performed for Si single crystal: as-grown, implanted with a 5×10$\text{}^{14}$ ions· cm$\text{}^{-2}$ dose of 3 MeV/n Ar ions, as well as implanted and annealed in a very high vacuum. The results are discussed on the basis of rocking curves and the mathematical analysis of the reciprocal space maps. It is shown that the lattice parameter is increased in an implanted part of the crystal, but long distance lattice curvature is not present. After annealing full relaxation of the crystal is stated.
Źródło:
Acta Physica Polonica A; 2002, 101, 5; 743-750
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electron Microscopy and X-ray Structural Investigations of Incommensurate Spin-Ladder Sr$\text{}_{4.1}$Ca$\text{}_{4.7}$Bi$\text{}_{0.3}$Cu$\text{}_{17}$O$\text{}_{29}$ Single Crystals
Autorzy:
Dłużewski, P.
Pietraszko, A.
Kozłowski, M.
Szczepańska, A.
Górecka, J.
Baran, M.
Leonyuk, L.
Babonas, G.-J.
Lebedev, O.
Szymczak, R.
Powiązania:
https://bibliotekanauki.pl/articles/2014560.pdf
Data publikacji:
2000-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.72.Nn
61.72.Mm
74.72.-h
61.16.Bg
61.10.-i
Opis:
Transmission electron microscopy and X-ray diffraction proved chain ladder incommensurate single crystal structure of investigated samples. The incommensurate ratio was determined from the X-ray and electron diffraction being equal to 0.704. Diffuse scattering intensities localised on the planes perpendicular to the c*-axis and passing through the spots originating from the periodicity of chain sublattice were detected. High-angle grain boundary or twinning formed by rotation of 33.3° around [100] direction was observed. High-resolution electron microscopy images revealed the stacking faults in ac planes.
Źródło:
Acta Physica Polonica A; 2000, 98, 6; 729-737
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of Si-Implanted and Thermally Annealed Layers of Silicon by Using X-ray Grazing Incidence Methods
Autorzy:
Klinger, D.
Lefeld-Sosnowska, M.
Pełka, J. B.
Paszkowicz, W.
Gierłowski, P.
Pankowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/2030709.pdf
Data publikacji:
2002-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.10.Kw
61.72.Tt
68.35.Fx
81.40.Ef
81.65.Mq
Opis:
This paper reports on the study of structural modifications induced by the implantation process and by the subsequent thermal annealing in near-surface layers of Si single crystals implanted with Si$\text{}^{2+}$ ions of energy 140 keV and doses from 1×10$\text{}^{15}$ to 1× 10$\text{}^{16}$ ions/cm$\text{}^{2}$. The grazing incidence X-ray diffraction and X-ray reflectivity measurements were applied to determine the thickness and structural composition of the damaged layers. The fitted electron density profiles indicated an existence of an interfacial layer with density higher than the density of Si matrix or near-surface oxide layer. Formation of polycrystalline phases of silicon and silicon oxides is discussed in dependence on the conditions of annealing treatment and implantation dose.
Źródło:
Acta Physica Polonica A; 2002, 101, 5; 795-801
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structural and Magnetic Properties of Dy(Fe,V,Si)$\text{}_{12}$ Compounds
Autorzy:
Drzazga, Z.
Winiarska, A.
Chrobak, A.
Kaczorowski, D.
Powiązania:
https://bibliotekanauki.pl/articles/1964633.pdf
Data publikacji:
1997-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.30.Gw
75.50.Gg
75.30.Cr
61.10.-i
Opis:
An influence of Si on the structural and magnetic properties of Dy(Fe,V,Si)$\text{}_{12}$ compounds is studied. X-ray diffraction shows that these materials crystallise in the tetragonal ThMn$\text{}_{12}$-type structure. An increase in the saturation magnetization, the Curie temperatures and magnetocrystalline anisotropy in the Si substitutional systems is observed when compared with DyFe$\text{}_{12-x}$V$\text{}_{x}$. The magnetic properties depend on the preferential site occupation and concentration of Si and V atoms in these compounds.
Źródło:
Acta Physica Polonica A; 1997, 92, 2; 335-338
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structural Chemistry and Magnetic Properties of $R_2Ni_{2-x}In$ (R=Gd-Er, x=0.22 or 0.3) Compounds
Autorzy:
Tyvanchuk, Yu.
Baran, S.
Jaworska-Gołąb, T.
Duraj, R.
Kalychak, Ya.
Szytuła, A.
Powiązania:
https://bibliotekanauki.pl/articles/1489895.pdf
Data publikacji:
2012-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.30.Cr
75.30.Kz
61.10.-i
61.66.Dk
75.40.Gb
75.50.Ee
Opis:
X-ray diffraction and magnetic measurements of $R_2Ni_{2 - x}In$ (R = Ho, Dy, x = 0.3 and R = Gd, Tb, Er, x = 0.22) compounds are reported. The compounds crystallize in the tetragonal $Mo_2FeB_2$-type crystal structure (space group P4/mbm). Magnetic measurements reveal antiferromagnetic order with the Néel temperatures $T_{N}$ equal to 26.4 K (Gd), 20.2 K (Tb), 8.3 K (Dy), 7.1 K (Ho), and 6.3 K (Er). For R = Gd, Tb and Er an additional phase transition below $T_{N}$ is observed at 13.5, 13.1, and 5.0 K, respectively.
Źródło:
Acta Physica Polonica A; 2012, 121, 3; 678-681
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hyperfine Interactions and Some Magnetic Properties of Nanocrystalline $Co_{40}Fe_{50}Ni_{10}$ and $Co_{50}Fe_{45}Ni_{5}$ Alloys Prepared by Mechanical Synthesis and Subsequently Heat Treated
Autorzy:
Pikula, T.
Oleszak, D.
Pękała, M.
Powiązania:
https://bibliotekanauki.pl/articles/1506594.pdf
Data publikacji:
2011-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.20.Ev
75.50.Kj
61.10.-i
76.80.+y
75.60.Ej
Opis:
$Co_{40}Fe_{50}Ni_{10}$ and $Co_{50}Fe_{45}Ni_{5}$ ternary alloys were prepared by mechanical alloying method. To check the stability of their structure thermal treatment was applied subsequently. As X-ray diffraction studies proved the final products of milling were the solid solutions with bcc lattice and the average grain sizes ranged of tens of nanometers. After heating of the $Co_{50}Fe_{45}Ni_{5}$ alloy up to 993 K the mixture of two solid solutions with bcc and fcc lattices was formed. In other cases thermal treatment did not change the type of the crystalline lattice. Mössbauer spectroscopy revealed hyperfine magnetic field distributions which reflected the different possible atomic surroundings of $\text{}^{57}Fe$ isotopes. Results of the macroscopic magnetic measurements proved that both investigated alloys had relatively good soft magnetic properties.
Źródło:
Acta Physica Polonica A; 2011, 119, 1; 52-55
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spectroscopic Studies of Poly(ε-Caprolactone)/Sodium Montmorillonite Nanocomposites
Autorzy:
Krzaczkowska, J.
Fojud, Z.
Kozak, M.
Jurga, S.
Powiązania:
https://bibliotekanauki.pl/articles/2043539.pdf
Data publikacji:
2005-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
91.60.-x
71.20.Tx
78.30.Jw
36.20.-r
33.25.+k
61.10.-i
Opis:
Polymer-layered silicate nanocomposites belong to a new class of hybrid materials consisting of organic-synthetic polymer matrix and inorganic filler-layered structure clay minerals. The paper presents the results of FTIR, NMR, and SAXS studies of poly(ε-caprolactone)/sodium montmorillonite nanocomposites. We observed a correlation between the concentration of poly(ε-caprolactone) in nanocomposite samples and structural changes both of the clay mineral and the intercalated polymer. Stiffening of the clay structure appears as a result of poly(ε-caprolactone) intercalation into a clay structure. $\text{}^{27}$Al NMR studies indicated in nanocomposites two non-equivalent sites of aluminium ions, i.e. in octahedral and tetrahedral coordination, whereas in the montmorillonite clay structure the aluminium ions are located in the interlayer space too. We found also that the temperatures of structural changes and softening process of poly(ε-caprolactone) chains in the nanocomposites depend on the concentration of poly(ε-caprolactone).
Źródło:
Acta Physica Polonica A; 2005, 108, 1; 187-196
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
X-Ray Microscopy and Spectromicroscopy
Autorzy:
Margaritondo, G.
Powiązania:
https://bibliotekanauki.pl/articles/1920890.pdf
Data publikacji:
1992-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.Lx
79.60.-i
Opis:
Progress in the instrumentation and, in particular, in the photon sources makes it possible to implement a number of established X-ray spectroscopies in a high-lateral-resolution mode. We discuss the general trends of this field, and then we present a detailed analysis of a particular and very interesting branch: photoemission spectromicroscopy. The results include a recent world record in lateral and energy resolution, obtained by the MAXIMUM system at Wisconsin, and microimages of materials science systems as well as of neuron networks.
Źródło:
Acta Physica Polonica A; 1992, 82, 2; 283-294
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spatially Resolved Chemistry on Bimetallic Surfaces
Autorzy:
Behm, R. J.
Powiązania:
https://bibliotekanauki.pl/articles/1968689.pdf
Data publikacji:
1998-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.16.Ch
68.10.Jy
82.65.-i
Opis:
The local chemical properties of bimetallic surfaces, which are often drastically different from those of each of the components, will be discussed. Using CO adsorption as a probe molecule it will be shown for two model systems, Au/Pd(111) and Pt/Ru(0001), that their chemical properties depend decisively on the local surface structure and that the correct interpretation of area integrating spectroscopic and kinetic data obtained from such surfaces requires detailed knowledge of their (defect) structure and of the distribution of the different components in the surface layer. It will further be shown that information on the local chemical properties of specific structural elements such as monolayer islands and monolayer island edges, and specific surface ensembles can be gained by applying high resolution scanning tunneling microscopy imaging and area integrating spectroscopic techniques in combination to bimetallic surfaces whose morphology and composition is varied in a systematic and controlled way. Based on experimental results adsorption on a monolayer A / substrate B system is suggested as a model for gaining information on the modifications in chemical properties of AB alloy surfaces due to metal-metal interactions.
Źródło:
Acta Physica Polonica A; 1998, 93, 2; 259-272
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Single Pulse Laser Ablation of AISI 316L Stainless Steel Surface Using Nd:YAG Laser Irradiation
Autorzy:
Demir, P.
Kacar, E.
Akman, E.
Demir, A.
Powiązania:
https://bibliotekanauki.pl/articles/1195232.pdf
Data publikacji:
2014-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
42.62.-b
44.05.+e
44.10.+i
61.82.-d
61.82.Bg
79.20.Eb
Opis:
The interaction of single-pulse Nd:YAG laser, operating at 1064 nm wavelength and 6 ns pulse duration, with AISI 316L stainless steel target surface was investigated experimentally and theoretically. Surface modification of stainless steel using laser irradiation was studied by observing the effects of varying incident laser pulse intensities on surface morphology. Surface structure of laser treated stainless steel was determined by optical microscopy and profilometry analyses. Numerical calculation by heat transfer equation was performed for single laser pulse irradiation. The results, obtained by theoretical and experimental processes, of the interaction between single-pulse Nd:YAG laser irradiation and AISI 316L stainless steel target surface are reported.
Źródło:
Acta Physica Polonica A; 2014, 125, 2; 439-441
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Variational Calculation of Bulk Moduli for Liquid Binary Alloys of Alkali Metals
Autorzy:
Dubinin, N.
Powiązania:
https://bibliotekanauki.pl/articles/1030333.pdf
Data publikacji:
2017-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
05.70.Ce
61.20.Ne
71.22.+i
62.10.+s
Opis:
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.
Źródło:
Acta Physica Polonica A; 2017, 131, 2; 237-239
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-60 z 60

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