FENIKS jest długoterminowym projektem mającym na celu odnowienie, popularyzację i wsparcie nauczania fizyki w szkołach II stopnia. Jest on przeprowadzany przez Uniwersytet Jagielloński, Uniwersytet Rzeszowski i Uniwersytet Jana Kochanowskiego w ich województwach na zasadzie partnerstwa. Projekt trwający trzy lata dociera do 250 szkół z ponad 2500 wybranych uczniów zorganizowanych przez nauczycieli w dziesięcioosobowe grupy. Działania programowe koncentrują się na eksperymentach fizycznych jako na kluczu do zrozumienia fizyki. Głównymi elementami projektu są przeprowadzane po godzinach lekcje fizyki w szkołach, ćwiczenia w laboratoriach uniwersyteckich, wykłady przedstawiające eksperymenty fizyczne, wizyty uczonych w szkołach, konkursy projektów naukowych przygotowanych przez uczniów, liga internetowa rozwiązywania zadań oraz obozy letnie i zimowe. Projekt jest finansowany przez Operational Programme Human Capital of the European Social Fund.
EN
FENIKS is a long-term project for restoration, popularization, and supporting the teaching of physics in secondary schools. It is carried out by the partnership of the Jagellonian University, the University of Rzeszow, and the Jan Kochanowski University in their voivodships. The project, lasting three years, reaches to 250 schools with over 2500 selected pupils organized by teachers in groups of ten. The program activities are focused on physics experiments as the key to undestanding physics. The main elements of the project are after-hour physics lessons at schools, exercises in the university laboratories, lectures displaying physics experiments, visits of scientists to schools, competitions of science projects prepared by the pupils, internet problem-solving league, and Summer/Winter camps. The project is financed from the Operational Programme Human Capital of the European Social Fund.
The Er2 xGdxFe14B (x = 0.5, 1.0, 1.5) and Er2 xThxFe14B (x = 0.0, 0.5, 1.0, 1.5, 2.0) polycrystalline compounds have been investigated with 57Fe Mössbauer spectroscopy and differential scanning calorimetry (DSC). A comparison of results related to spin reorientation phenomena obtained for Gd- and Th-substituted compounds is presented in this paper. Spin reorientation phenomena (changes from planar to axial spin arrangements) have been studied extensively by a narrow step temperature scanning in the neighbourhood of the spin reorientation temperature, TSR. From the analysis of Mössbauer spectra, it was deduced that in the region of transition each subspectrum was split into two Zeeman sextets, which were characterised by different hyperfine magnetic fields and quadrupole splittings. A consistent way of fitting the spectra in the wide range of temperatures was proposed. The composition and temperature dependencies of hyperfine interaction parameters and subspectra contributions were derived from fits and the transition temperatures were determined for all the compounds studied. DSC studies proved that the spin reorientations were accompanied by thermal effects for all compositions of the Gd- and for x = 0.5 of the Th-series. Transformation enthalpy and TSR were determined from these studies and the two-stage character of transition was confirmed. Magnetic spin arrangement diagrams for R = Th and Gd series were constructed and compared using combined data obtained with both methods.
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The Er2 xGdxFe14B (x = 0.5, 1.0, 1.5) polycrystalline compounds have been investigated with 57Fe Mössbauer spectroscopy in the 80 330 K temperature range. The spin reorientation phenomena (changes from planar to axial spin arrangements) have been studied extensively by a narrow step temperature scanning in the neighbourhood of the spin reorientation temperature. From the analysis of the spectra it was deduced that in the region of transition each subspectrum was split into two Zeeman sextets, which were characterized by different hyperfine magnetic fields and quadrupole splittings. A consistent way of describing the Mössbauer spectra in the wide range of temperatures was proposed. The composition and temperature dependencies of hyperfine interaction parameters and subspectra contributions were derived from experimental spectra. The transition temperatures were determined for all the compounds studied.
Two isostructural series of polycrystalline compounds: Er2-xYxFe14B and Er2-xCexFe14B have been studied by 57Fe Mössbauer spectroscopy in the temperature range 80-370 K. The spin reorientation phenomenon (a transition from basal plane to axial easy magnetisation direction) has been studied extensively by a narrow step temperature scanning in the vicinity of the transition. Using the procedure of subtracting the Mössbauer spectra taken for the same compound at different temperatures, it was possible to follow the influence of transition on the shape of spectra. From this procedure it was concluded that in the region of transition each subspectrum splits into two Zeeman sextets, which are characterised by different hyperfine magnetic fields and quadrupole splittings. The consistent way of describing the Mössbauer spectra was proposed. The spin reorientation temperatures have been established for all compositions and compared with the values obtained from theoretical calculations of spin orientation angle based on phenomenological model. The spin arrangement diagrams have been constructed.
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