Wyniki wyszukiwania - BazTech

1

Thermal treatment effect on dynamics of luminescent states in oxyfluoride glass-ceramics doped with Pr3+ and Tb3+

Dominiak-Dzik G., Klimesz B., Ryba-Romanowski W.

Optica Applicata

|

2010

|

Vol. 40, nr 2

375--382

EN

The 50GeO2–(50–x–y)PbO–yPbF2–xLnF3 glass single doped with Pr3+ and Tb3+ ions was studied. The composition of the material was modified by varying the content of both PbF2 (y = 5, 10, 15 mol%) and LnF3 (x = 0.2 and 2 mol%). The differential thermal analysis (DTA) of as-melted samples was used to determine thermal characteristics. Optical techniques and kinetics measurements were used to monitor the effect of thermal treatment on spectroscopic properties and dynamics of luminescent states of optically-active ions in amorphous and two-phase systems. It was found that non-exponential decays of praseodymium luminescence in as-melted material become exponential or nearly exponential with corresponding longer lifetimes in thermally-treated samples. This effect was not so strong in the Tb3+-doped glass. The influence of the PbF2 content on luminescence dynamics was studied for samples doped with 2 mol% of Pr3+. It was observed that the increase of PbF2 content leads to lengthening of luminescence lifetime, e.g., the 1D2 lifetime increases from 4.1 to 45 ?s in 5 and 15 mol% of PbF2 as-melted samples, respectively.

2

Nd3+ or Sm3+ doped oxyfluoride glass based on GeO2-PbO-PbF2. Synthesis and spectroscopic properties

Klimesz B., Dominiak-Dzik G., Ryba-Romanowski W.

Optica Applicata

|

2005

|

Vol. 35, nr 4

843-850

EN

Glasses with composition 50 GeO2-(45 - x)PbO-5 PbF2-x LnF3 (Ln = Nd or Sm, x = 0.2 and 2 mol%) were synthesised in the bulk form. Phase profiles and temperature characteristics were measured by differential thermal analysis (DTA); glass transition temperature Tg, as well as the b-PbF2 Tb and oxide glass crystallisation Tc temperatures have been derived for each individual system. A study of optical properties (absorption, emission) of the PbF2-Nd3+ and PbF2-Sm3+ was carried out. The oscillator strengths were obtained for several optical transitions and they have been used to calculate phenomenological intensity parameters W2, 4, 6. The probabilities of radiative transitions from fluorescent levels of Nd3+ and Sm3+ ions, as well as branching ratios and radiative lifetimes, were estimated on the basis of the Judd-Ofelt framework. The fluorescence dynamics of studied systems was measured. Experimental lifetimes were compared and discussed with those obtained with the Judd-Ofelt theory.

3

Zestaw pomiarowy do detekcji przemian fazowych metodą emisji akustycznej

Klimesz B., Krupa R., Górecki C., Górecki T.

Zeszyty Naukowe. Fizyka / Politechnika Opolska

|

1998

|

z. 21

31-40

PL

Opisano budowę i działanie termosonimetru - aparatury pomiarowej do badań przemian fazowych metodą emisji akustycznej, zbudowanej w Zakładzie Fizyki Politechniki Opolskiej. Przedstawiono także wyniki testu zestawu pomiarowego na przykładzie przemian fazowych (topnienie, przemiany polimorficzne) bizmutu (Bi), indu (In) i azotanu potasu (KNO3).

EN

The paper presents the construction and operation mode of thermosonimeter - a measuring apparatus for detection of phase transitions with the use of acoustic emission effect - built in the Physical Laboratory of the Opole Technical University. The test of the measuring apparatus has also been performed on the example of phase transitions (melting, polymorphic phase changes) in bismuth (Bi), indum (In) and potassium nitrate (KNO3).