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Excitation and luminescence of Dy^(3+) ions in PbO-P_2O_5-Ga_2O_3 glass system

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journal of Rare Earths 2014年第3期32卷 213-216页

作者： M.Soltys L.Zur j.pisarska W.A.Pisarski Institute of Chemistry University of Silesia

Lead phosphate glasses singly doped with Dy^3＋ ions were studied. The samples were prepared in a glove box in order to eliminate hydroxyl groups. Local structures were examined using FT-IR. Excitation and luminescence spectra for Dy^3＋ ions in inves- tigated lead phosphate glasses were registered. Luminescence intensity ratio Y/B related to 4F9/2→^6Hj/2 （where j=15, 13） transitions was determined and luminescence lifetime （ζm） for the 4F9/2 state of Dy^3＋ions were also measured.

关键词： phosphate glasses Dy^3+ ions luminescence rare earths

Local structure and luminescent properties of lead phosphate glasses containing rare earth ions

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journal of Rare Earths 2011年第12期29卷 1157-1160页

作者： j.pisarska L.Zur T.Goryczka W.A.Pisarski Institute of Chemistry University of Silesia Institute of Materials Science University of Silesia

Local structure and luminescent properties of lead phosphate glasses containing rare earth ions were studied. Optically active ions such as Eu^3＋, Dy^3＋, Tb^3＋ and Er^3＋ were chosen as dopants. The local structure was verified using X-ray diffraction and Fourier transform inflared （FT-IR） spectroscopy. The visible luminescence bands recorded for the studied samples corresponded to ^5D0→^7Fj （j=0÷4） transitions of Eu^3＋, ^4F9/2→^6Hj/2 （j=11÷15） transitions of Dy^3＋, ^5D3→^7Fj, （j＇=1÷6） and ^5Da→^7Fj （j=3÷6） transitions of Tb^3＋, and ^4S1/2→^4I15/2 transitions of Er^3＋.

关键词： lead phosphate glasses rare earth ions local structure luminescent properties

Up-conversion processes of rare earth ions in heavy metal glasses

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journal of Rare Earths 2011年第12期29卷 1192-1194页

作者： L.Grobelny W.A.Pisarski j.pisarska R.Lisiecki W.Ryba-Romanowski Institute of Chemistry University of Silesia Institute of Low Temperature and Structure Research Polish Academy of Sciences

Heavy metal lead germanate glasses doubly doped with Yb^3＋ and Ln^3＋ ions （Ln=Er, Tin） were investigated. Up-conversion spectra of Er^3＋ and Tm^3＋ were registered under diode-laser excitation of Yb^3＋. Up-conversion luminescence bands corresponded to ^4S3/2→^4I15/2 （green） and ^4F9/2→^4I15/2 （red） transitions of Er^3＋ as well as ^1G4→^3H6 （blue） and ^3Ha→^3H6 （N]R） transitions of Tm^3＋, respectively.

关键词： heavy metal glasses rare earth ions up-conversion luminescence

Energy transfer processes from Yb^(3+) to Ln^(3+) (Ln=Er or Tm) in heavy metal glasses

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journal of Rare Earths 2014年第3期32卷 273-276页

作者： A.Kos I.Czopek j.pisarska W.A.Pisarski R.Lisiecki W.Ryba-Romanowski University of Silesia Institute of Chemistry Institute of Low Temperature and Structure Research

Heavy metal glasses doubly doped with Yb3＋ and Ln3＋ ions （Ln=Er or Tm） were studied. Glass host matrices were limited to lead borate glass and lead germanate glass. Efficient resonant （yb3＋-Er3＋） and non-resonant （yb3＋-Tm3＋） energy transfer was ob- served for the studied systems. Near-infrared luminescence spectra at 1.53 μm （Er3＋） and 1.9 gm （Tm3＋） were detected under excita- tion of Yb3＋ by 975 nm diode laser line. They corresponded to 4I13/2→4115/2 （Er3＋） and 3F4→3H6 （Tm3＋） transitions of rare earth ions, respectively. The unusual large spectral linewidth nearly close to 110 nm for 4I13/2→4I15/2 transition of Er3＋ ions in lead borate glass was obtained, whereas long-lived near-infrared luminescence at 1.53 gm was detected in lead germanate glass. Quite different situa- tion was observed for yb3＋-Tm3＋ doubly doped glasses. In contrast to lead borate glass, near-infrared （3F4→3H6） luminescence spectra were registered for Tm3＋ ions in lead germanate glasses, only. These phenomena strongly depended on stretching vibrations of glass host, which was confirmed by FT-IR spectroscopy.

关键词： heavy metal glasses rare earth ions energy transfer NIR luminescence

Seismites resulting from high-frequency, high-magnitude earthquakes in Latvia caused by Late Glacial glacio-isostatic uplift

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journal of Palaeogeography 2016年第4期5卷 363-380页

作者： A.j. (Tom) van Loon Matgorzata pisarska-jamrozy Maris Nartiss Maris Krievans juris Soms Geocom Consultants Valle del Portet 17 03726 Benitachell Spain Institute of Geology Adam Mickiewicz University Makow Polnych 16 61-606 Poznan Poland Faculty of Geography and Earth Sciences University of Latvia Rainis Blvd. 19 1576 Riga Latvia Department of Geography Daugavpils University Parades 1 LV 5401 Daugavpils Latvia

Geologically extremely rapid changes in attitude by glacial rebound of the Earth crust after retreat of the Scandinavian Ice Sheet at the end of the last Weichsetian glaciation influenced the patae- ogeography of northern Europe. The up（ift of the Earth crust apparently was not gradual, but shock-wise, as the uplift was accompanied by frequent, high-magnitude earthquakes. This can be deduced from strongly deformed layers which are interpreted as seismites. Such seismites have been described from several coun- tries around the Baltic Sea, including Sweden, Germany and Poland. Now similarly deformed layers that must also be interpreted as seismites, have been discovered also in Latvia, a Baltic country that was covered by an ice sheet during the last glaciation. The seismites were found at two sites： Near Vatmiera in the NE part and near Rakuti in the SE part of the country. The seismites were found in sections of about 7 m and 4.5 m high, respectively, that consist mainly of glaciofluvial and gtaciotacustrine sands and silts. At the Vatmiera site, 7 seismites were found, and at the Rakuti site these were even 12 seismites. The two sections have not been dated precisely up tilt now, but lithological correlations and geomorpho- logical characteristics suggest that the sediments at the Vatmiera site cannot be older than 14.5 ka. Because the accumulation of the section did not take more than about 1000 years, the average recurrence time of the high-magnitude （M≥4.5-5.0） earthquakes must have been maximally only 100-150 years, possibly only 6-7 years. The sediments at Rakuti must also have formed within approx. 1000 years （17-16 ka）, implying a recurrence time of high-magnitude earthquakes of maximaUy once per 100-200 years.

关键词： Soft-sediment deformation structures (SSDS) Seismites Latvia Glacio-isostatic rebound,Earthquake recurrence time