Wyniki wyszukiwania - BazTech

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Suszony wywar z procesu wytwarzania bioetanolu z kukurydzy jako dodatek paszowy stosowany w żywieniu przeżuwaczy

Zachwieja A., Kupczyński R., Bodarski R., Paczyńska K., Miśta D., Pecka E, Zawadzki W, Tumanowicz J, Adamski M

Przemysł Chemiczny

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2013

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T. 92, nr 6

1050--1055

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An application of Mössbauer spectroscopy in the studies of iron - molybdenum silica mesoporous materials

Surowiec Z., Wiertel M., Marynowska A., Gac W., Zawadzki W.

Nukleonika

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2013

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Vol. 58, No. 1

137-141

EN

Iron-molybdenum silica mesoporous materials were obtained by the application of direct hydrothermal method. Four samples with different metal contents relative to silica were investigated. Incorporation of iron and molybdenum ions in the synthesis stage led to structural changes of the MCM-41 support. With an increasing metals content, cylindrical pores of silica initially transformed into bottle-ink type pores, and then into the slit-like ones. Mössbauer spectroscopy investigations indicated that Fe ions were embedded in the silica walls and then formed nanosized crystallites in the pores. Superparamagnetic phase was observed at liquid nitrogen temperature.

3

Application of fiber Bragg gratings for strain measurement in historic textiles and paintings on canvas

Zawadzki W., Bartosik M., Dzierzega K., Bratasz L., Lukomski M., Peacock E.

Optica Applicata

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2012

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Vol. 42, nr 3

503-517

EN

The aim of this work was to evaluate the applicability of optical fiber Bragg grating (FBG) sensors to the monitoring of deformation in historical textiles and paintings on canvas. Fibers with a ceramic coating were selected for strain investigation in textiles due to both their almost perfect strain transfer and much shorter relaxation times compared to fibers with an acrylate coating. FBG sensors were attached to fabrics in a non-destructive manner using specially designed magnetic clamps. Local strain measurements using these sensors were consistent with general strains measured using either a universal testing machine (UTM) or a laser triangulator when varying external load or relative humidity. However, strain magnitudes measured by the different methods were comparable only after correction for the influence of the fiber on the textile under study. Strain measurements in model paintings on canvas were carried out using uncoated fibers embedded in the gesso layers on the canvas. Despite some drawbacks, the FBG sensors were found to be useful in monitoring strain in historic textiles and consequently, for the assessment of environmental risk of these works-of-art.

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Półwzględność w półprzewodnikach

Zawadzki W.

Postępy Fizyki

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1998

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T. 49, z. 5

237-246

EN

A theoretical and experimental analogy is traced between behaviour of electrons in narrow-gap semiconductors and that of relativistic electrons in vacuum. Beginning with the similarity of energy-momentum realations for both systems, we consider various effects in the presence of a magnetic field and in crossed electric and magnetic fields. Finally, the relativistic "Zitterbewegung" of electrons in semiconductors is described and its possible cosequences are discussed.