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1.
P. Byszewski E. Kowalska R. Diduszko 《Journal of Thermal Analysis and Calorimetry》1995,45(5):1211-1216
Fullerences C60 with adamantane (C10H16), hexamethylotetramine (HMT, C6H12N4) or 1,4-diazabicyclooctane (DABCO, C6H12N2) crystallize, at the relative concentration C60/guest=2/1, in the pseudotetragonal lattice in which C60 retains almost the same positions as in pure fullerides. The ‘guest’ molecules occupy the octahedral interstitial sites. The mixed crystals which exhibit interesting physical properties are thermally unstable. The decomposition starts at 40–50°C. 相似文献
2.
We optimize the composition of tellurite glass for the manufacture of photonic crystal fibers with a large spectrum of transparency. The glasses, synthesized in four and five component (TeO2-WO3-Na2O-Nb2O5 and TeO2-WO3-PbO-Na2O-Nb2O5) oxide systems with variable contents of WO3 (5-38 mol%) and PbO (0-18 mol%), are designed and manufactured, and the transmission properties of the obtained glasses for the spectral range of 200 nm-7 μm have been determined. Thermal expansion coefficients and glass characteristic temperatures are determined by the dilatometer and Leitz heat microscope methods. Differential Scanning Calorimetry (DSC) measurements as well as crystallization tests by isothermal heat treatment are used to measure the thermal stability of the glasses and their ability to crystallize. Diffractive X-ray (XRD) measurements are used to determine the crystalline phases of the glass samples and the glasses with the highest resistance to recrystallization during thermal treatment were selected and used for the manufacture of photonic crystal fibers. 相似文献
3.
E. Kowalska J. Radomska P. Konarski R. Diduszko J. Oszczudłowski T. Opalińska M. Więch Z. Duszyc 《Journal of Thermal Analysis and Calorimetry》2006,86(1):137-140
Two components
of electronic wastes (sample A – a mixture of three types of printed
circuit boards, sample B – a mixture of electronic junctions with metal
wires) were investigated using thermogravimetric analysis (TG). Thermogravimetric
and derivative thermogravimetric data (TG and DTG) give information on the
thermal stability of A and B samples and allows finding the correct conditions
for their degradation using pyrolysis in an experimental system, built on
the laboratory scale for utilization of hazardous wastes. X-ray fluorescence
measurements prove that brominated flame retardant is present in sample A,
whilst chlorinated flame retardant is a probable component of sample B. Preliminary
liquid chromatography of oil products obtained as a result of thermal waste
degradation shows that the hydrocarbons released during pyrolysis could be
used as a fuel. 相似文献
4.
K. Kołodziejak S. Turczyński R. Diduszko L. Klimek D. A. Pawlak 《Opto-Electronics Review》2006,14(3):205-211
Eutectics are the materials with foreseen application in the field of photonic crystals and metamaterials. In this paper,
the dependence on chemical composition of the microstructures of terbium-scandium-aluminium gamet and terbium-scandium perovskite
(Tb3Sc2Al3O12-TbScO3) eutectics has been studied. The growth of the eutectic rods by the micro-pulling down method is presented, using compositions
with several different volume fractions of the garnet and the perovskite phases, VTSAG:VTSP = 4, 3, 2, 1, 1/2. The phases have been characterized by powder X-ray diffraction and energy dispersive spectrometry. The
relationship between the lattice constant of individual phases and the chemical composition is presented. The unidirectional
growth of microrods has been also investigated by electron backscattering diffraction. 相似文献
5.
Byszewski P. Kowalska E. Diduszko R. Aleksiyko R. Berkowski M. Fink-Finowicki J. Kapuśniak J. 《Journal of Thermal Analysis and Calorimetry》2001,65(2):545-551
The solid solution crystals, La1–xNdxGaO3 and La1–xPrxGaO3 have been studied by differential scanning calorimetry method; the crystals exhibit the first order phase transition, the
temperature of the transition linearly increases with the concentration of Pr or Nd. The structure of the crystals has been
determined by X-ray diffraction. The correlation between the phase transition temperature and crystalline structure at the
temperature of the phase transition in both solid solution families is discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
6.
Urszula Brykała Henryk Tomaszewski Ryszard Diduszko Helena Węglarz Agata Sidorowicz Anna Wajler Katarzyna Jach Jacek Jagielski 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(1):637-641
The ability of gadolinium zirconate pyrochlore for actinides incorporation in its lattice makes this material a possible matrix for the immobilization of nuclear wastes. The aim of the presented work was to develop a novel method of gadolinium zirconate synthesis by using a reactive sintering procedure under high pressure based on commercial ZrO2 and Gd2O3 nanopowders. Samples were analyzed using X-ray diffraction and SEM to check their phase composition and microstructure. The obtained sintered pellets demonstrated peaks characteristic for pyrochlore structure for a wide range of preparation temperatures and high density (99.5 % of the theoretical value). It was found that the resulting materials exhibited a homogeneous microstructure and the average grain size dependent on sintering temperature. 相似文献
7.
L. Lipiska W. Ryba‐Romanowski A. Rzepka S. Ganschow R. Lisiecki R. Diduszko A. Pajczkowska 《Crystal Research and Technology》2009,44(5):477-483
The structural and optical features of gallium gadolinium garnet (GGG) nanopowders doped with neodymium were investigated. Nanopowders of GGG:Nd were prepared by modified sol‐gel method using acetic acid as complexing agent. This way permitted to incorporate large amounts of dopant (up to 10 %) without destroying garnet structure. Small single crystals of Nd:GGG were grown by a μ‐pulling down method and spectroscopic features of nanopowders and their single crystal counterparts were compared. It has concluded that the Nd3+ ions are located preferentially in the same type of sites in crystal lattices of GGG:Nd nanopowders and their single crystal counterparts. In addition, it follows from the perfect agreement of emission wavelengths and line width recorded for nanopowders and single crystal samples that the crystal lattice of GGG in nanopowders is not distorted. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
8.
P. Byszewski E. Kowalska R. Diduszko 《Journal of Thermal Analysis and Calorimetry》1995,45(5):1205-1210
Iron in the fullerite lattice binds fullerences in a sandwich type C60FeC60 complexes. At the concentration C60Fe2 it crystallizes in the monoclinic lattice. The structure is thermally unstable, with the energy release of 606 kJ·mol?1 it returns to fee lattice. Two possible sites in the reconstructed fee lattice are discussed, Fe bond to C60 and Fe inside the C60 cage. 相似文献
9.
L. Lipiska A. Rzepka R. Ryba‐Romanowski D. Klimm S. Ganschow R. Diduszko 《Crystal Research and Technology》2009,44(2):146-152
The nanocrystalline powders of Y4Al2O9 (YAM) pure and doped by Nd, Yb and codoped by Nd and Yb were obtained via modified sol‐gel method. These powders were characterized by X‐ray diffraction method, scanning electron microscopy and high resolution scanning electron microscopy, luminescence spectroscopy and differential thermal analysis (DTA). We obtained single phase powders of crystalline structure with average size 70 nm exhibiting interesting luminescent properties. Efficient non‐radiative energy transfer between Nd and Yb was found. DTA confirmed the phase transition at about 1400 °C. From these nanocrystalline powders, the crystals YAM:Yb, YAM:Yb,Nd were grown by micro‐pulling down technique. They were cracking during cooling owing to the phase transition. Luminescent properties of YAM:Nd,Yb crystals were identical with properties of corresponding nanopowders within experimental incertitude. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
10.
Kowalska E. Byszewski P. Diduszko R. Huczko A. Mieczkowski J. 《Journal of Thermal Analysis and Calorimetry》1998,54(1):197-202
The crystalline solvates containing fullerenes and (di)methylnaphthalenes were investigated by thermal analyses and X-ray
diffraction methods. It was found that C60 with (di)methylnaphthalenes forms two types of stable solvates: either at the molar ratio 1:2 decomposing at temperatures
close to 100°C or at 1:1 molar ratio decomposing in the temperature range 120–214°C. Crystalline lattice and thermal stability
of the solvates depends on the structure of the solvent molecules. The strong solute-solvent interaction is also manifested
by the modification of the C60 absorption spectra in solution. The results are discussed using semiempirical quantum chemistry methods.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献