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Magnetic characterization of microcrystalline Na3Ln0.99–xEr0.01Crx(PO4)2 orthophosphates synthesized by Pechini method (Ln = La, Gd)

Kaczmarek S. M., Leniec G., Fuks H., Skibiński T., Pelczarska A., Godlewska P., Hanuza J., Szczygieł I.

Materials Science Poland

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2017

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Vol. 35, No. 4

733--745

EN

Na3Ln(PO4)2 orthophosphates (Ln = La, Gd) doped with Er3+ and co-doped with Cr3+ ions were synthesized by Pechini method and characterized by electron paramagnetic resonance (EPR) and magnetic susceptibility measurements. Low temperature EPR spectra were detected and analyzed in terms of temperature dependence and the structure of the obtained materials. They show that erbium and chromium ions substitute Ln3+ and also Na+ ions or Na+ channels forming complex EPR spectra. Both kinds of ions reveal ferromagnetic type of interaction which shows some anomaly at the temperature between 10 K and 15 K. Magnetic susceptibility reveals a weak antiferromagnetic kind of interaction dominating in the whole temperature range, from 3.5 to 300 K.

2

Mechanobiology of soft tissues: FT-Raman spectroscopic studies

Gąsior-Głogowska M., Komorowska M., Hanuza J., Mączka M., Będziński R., Kobielarz M.

Challenges of Modern Technology

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2011

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Vol. 2, no. 3

8--11

EN

FT-Raman spectroscopy was used to investigate microstructural changes in the secondary protein structure of soft tissues subjected to increasing levels of macroscopic strain. Main protein bands at 938 cm-1 assigned as v(Cα–C), 1668 cm-1 — amide I and 1268 cm-1 — amide III are sensitive to applied strain and undergo wavenumber shifting. Other main vibrational modes at 1004 cm-1 assigned to the phenyl ring breathing mode and 2940 cm-1 (n(CH3,CH2)) remain unaltered. Spectroscopic results were compared with the mechanical relations obtained from the standard protocol of uniaxial tensile tests carried out in a testing machine. A clear correlation between Raman band shifting and the level of mechanical stress was established. Initially the load is transferred through elastin and then gradually also by collagen. It was proved that transferring loads by soft tissues involves changes in structural protein conformation. This process was described in detail for a tendon. It was also confirmed that mechanical properties of soft tissues depend on collagen and elastin fiers orientation.

3

Structural alteration of collagen fibres - spectroscopic and mechanical studies

Gąsior-Głogowska M., Komorowska M., Hanuza J., Ptak M., Kobielarz M.

Acta of Bioengineering and Biomechanics

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2010

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Vol. 12, no. 4

55-62

EN

Fourier Transform Near Infrared Raman Spectroscopy has been used to monitor the molecular changes of collagen in a tendon subjected to strain. In the Raman spectrum of the unstrained tendon, some protein bands, mainly assigned to collagen, can be observed: amide I (1666 cm–1) and III (1266 and 1248 cm–1) vibrational modes and skeletal (C–C) stretching vibrations (816 and 940 cm–1). The position of these bands is changing with the increasing strain values. It is concluded that elastin and non-helical domains of collagen are initially involved in the load transfer and triple helices of collagen are gradually joining this process.

4

Vibrational spectra, electronic excited states and magnetic properties of the copper(II) ions in alkylaminoacetylurea complexes

Ciurla H., Hanuza J., Talik Z., Korabik M., Mrozinski J.

Materials Science Poland

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2009

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Vol. 27, No. 1

5--21

EN

Copper(II) complexes with alkylaminoacetylurea ligands were synthesized and studied by means of IR, Raman, electron absorption and luminescence spectroscopies, as well as by ESR and magnetic methods. The spectroscopic and magnetic studies were performed in the 4-300 K and 1.9-300 K temperature ranges, respectively. The Cu2+ ions in these complexes are four coordinated having distorted squareplanar surroundings. The dependence of the spectroscopic parameters on the alkyl radical of the ligand is discussed. At low temperatures, very weak ferromagnetic interactions are observed for the C3 and C5 alkyls, and an antiferromagnetic one is observed for the remaining complexes, with C4 and C6-C18 alkyls.

5

Właściwości skóry ludzkiej uzyskane w testach mechanicznych i techniką spektroskopii Ramana

Szotek S., Będziński R., Kobielarz M., Gąsior-Głogowska M., Komorowska M., Maksymowicz K., Hanuza J., Hermanowicz K.

Engineering of Biomaterials

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2009

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Vol. 12, no. 89-91

207--209

PL

Celem przeprowadzonych badań było porównanie charakterystyk otrzymanych: w testach wytrzymałościowych i z pomiarów spektroskopowych. W pracy wyznaczono podstawowe parametry mechaniczne skóry, które są zdeterminowane ułożeniem włókien kolagenowych. Następnie zarejestrowano widma ramanowskie badanej tkanki, zidentyfikowano pasma charakterystyczne dla białka kolagenowego. Na podstawie analizy uzyskanych wyników, dla kolejnych etapów rozciągnięcia skóry, zaobserwowano między innymi różnice w położeniu maksimum pasma amidu I (1658cm-1) w zależności od kierunku rozciągania próbki. Porównanie, w obu metodach charakterystycznych zakresów, zachodzących zmian wykazało możliwość stosowania Spektroskopii Ramana w celu wyznaczenia kierunku ułożenia włókien kolagenowych w trakcie rozciągania co jest istotne z punktu widzenia przeszczepów skóry.

EN

The aim of the investigations was to compare the characteristics obtained from strength tests and spectroscopic measurements. The basic skin parameters dependent on the arrangement of collagen fibres were determined. Then Raman spectra of the investigated tissue were recorded and bands characteristic of collagen protein were identified. An analysis of the results for the successive stages of skin stretching showed, among other things, differences in the location of the amid I band maximum (1658cm-1) depending on the direction of specimen stretching. A comparison of the characteristic ranges of change determined by the two methods showed that Raman spectroscopy can be used to ascertain the orientation of collagen fibres in the course of stretching, which information is essential for skin transplantation.

6

Molecular impurity ions as centres with charge transfer degrees of freedom. Influence on ferroelectric phase transitions.

Vikhnin V. S., Maksimowa T. I., Hanuza J.

Materials Science Poland

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2005

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Vol. 23, No. 3

677--684

EN

The concept of molecular impurity ions (MI) as centres with charge transfer degrees of freedom, interacting (through the order parameter of the phase transition) with local vibrations and non-soft phonons, as well as with light, has been developed. It has been shown that MI can significantly influence a ferroelectric phase transition (FPT) due to a direct interaction of their specific charge transfer degrees of freedom with the ferroelectric order parameter. In this work, we predict a significant increase of the FPT critical temperature when increasing the MI concentration. The e MnO4- molecular impurity ions embedded in ferroelectric crystals (e.g. molybdates, tungstates, chromates, phosphates) are considered as possible candidates capable of inducing this effect.

7

Synthesis and characterization of metastable CeO2-ZrO2 solid solution obtained by polymerized complex method

Miśta W., Rayment T., Hanuza J., Macalik L.

Materials Science Poland

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2004

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Vol. 22, No. 2

153--170

EN

The paper describes the preparation and characterization of nano-size metastable tetragonal CeO2–ZrO2 mixed oxides prepared by a polymerized complex method. A glycine–ethylene glycol solution containing Ce3+ and Zr4+ ions was polymerized at 80–110 °C to form a viscous transparent resin without any visible precipitation. After heat-treatment at relatively low temperature (ca 250 °C) on a hot plate in static air, the solid precursor ignited in part due to self-combustion, resulting in the formation of a nanocrystalline, compositionally-homogeneous solid solution. Its structure was confirmed using X-ray diffraction, HRTEM and Raman spectroscopy. The phase separation in CeO2–ZrO2 system on a subsequent heat-treatment in air and in a mixture of H2 and He was also investigated up to 1100 °C.

8

Luminescence properties of Eu3+-doped Al2(WO4)3

Macalik L., Hanuza J., Hermanowicz K., Godlewska P., Sidorov N. V.

Materials Science Poland

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2004

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Vol. 22, No. 2

145--152

EN

Emission spectra of Al2(WO4)3 doped with Eu3+ were recorded at room temperature (orthorhombic phase) and at 10 K (monoclinic phase). The luminescence excitation spectra and luminescence decay profiles were recorded for both structural modifications at RT and LN2T, and the luminescence lifetimes of Eu3+ have been estimated. Two-site behaviour of the optically active ions in both phases has been revealed in the luminescence studies. However, the emission decay profiles give one lifetime of the 5D2 level, equal to 1.8 ms and 848.4 žs at room temperature and liquid nitrogen temperature, respectively. The results obtained have been explained in terms of an unusual location of Eu3+ ions inside the crystal tunnels, parallel to the c-axis.

9

The bismuth - doping effect on the Jahn-Teller phase transition in CsDy(MoO4)2 crystal

Gerashchenko S. S., Miloslavskaya O. V., Kharchenko Y. N., Kut'ko V. I., Nesterenko N. M., Macalik L., Hermanowicz K., Mączka M., Hanuza J.

Materials Science

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2002

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Vol. 20, No. 2

81-89

EN

Using spectroscopic and visual optical methods the shift of the critical temperature (Ttr~42K) of the first-order phase transition of the Jahn-Teller type to the lowtemperature side at doping the CsDy(MoO4)2 crystal with Bi3+ (concentration up to x~0.08) was revealed. Effect of the doping is compared to the effect of uniaxial pressure. Using the result of the Zeeman effect we have calculated the critical value Hc of external magnetic field at which the spontaneous change of the sizes of crystal is suppressed under magnetic field and the high-temperature phase may be induced at T=0°K. It is supposed that doping with Bi3+ leads to decrease of the critical magnetic field value for doped CsDy(MoO4)2 .

10

Study of thermal disordering of the KSc(WO4)2 crystal structure by Raman spectroscopy

Mączka M., Hanuza J., Sidorov N., Kojima S.

Materials Science

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2002

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Vol. 20, No. 1

105--110

EN

Raman spectra of KSc(WO4)2, exhibiting three reversible phase transitions from a trigonal phase to monoclinic and triclinic structures, have been studied in the temperature region of 100-294 K. The mea surements have revealed the presence of significant broadening of librational and translational modes of the WO2 4 ions with increasing temperature. This broadening was explained as a result of anisotropic activation of the complex ion reorientations.