Wyniki wyszukiwania - BazTech

1

Structural and optical properties of Dy3+ doped Sr2SiO4 phosphors

Verma Durga, Patel R. P., Verma Mohan L.

Materials Science Poland

|

2019

|

Vol. 37, No. 1

55--64

EN

Dysprosium doped strontium silicate phosphor namely (Sr2SiO4:Dy3+) was prepared by low-temperature solution combustion method using urea (CO(NH2)2) as a fuel. The material was characterized by powder X-ray diffraction (XRD), FT-IR, SEM and EDX. The average crystallite sizes was calculated by Scherer formula. Thermoluminescence study was carried out for the phosphor which showed single glow curve. The kinetic parameter were calculated by using Chen’s glow curve method. Photoluminescence spectra revealed strong transition at 473 nm (blue), 571 nm (yellow) and weak transition at 645 nm (red). These peaks were assigned to transition 4F9/2 → 6H15/2, 13/2 , 11/2. CIE graph of Sr2SiO4:Dy3+phosphor is suitable for the generation of white light emission.

2

Optical properties of Sr2SiO4:Eu2+, Dy3+ phosphors prepared by combustion method

Verma D., Patel R. P., Verma M. L.

Materials Science Poland

|

2018

|

Vol. 36, No. 3

387--396

EN

In the present paper, TL and PL study of Dy3+ doped Sr2SiO4:Eu2+ phosphor is reported. A polycrystalline sample of Sr2SiO4:Eu2+, Dy3+ was prepared by combustion method. The obtained phosphor was characterized by powder X-ray diffraction, scanning electron microscopy, UV-Vis spectroscopy, PL and thermoluminescence. The results of the XRD studies obtained for Sr2SiO4:Eu2+, Dy3+ phosphor revealed its monoclinic structure. The average crystallite size was calculated as 12.77 nm. Thermoluminescence study was carried out for the phosphor using UV irradiation and a single glow peak was found. The thermoluminescence glow curves of the samples were measured at various concentrations of co-dopant. The kinetic parameter has been calculated using Chen’s glow curve method. In this paper, the photoluminescence and afterglow behaviour of these phosphors are reported.

3

Oznaczanie halogenów w biogazie

Holewa J., Szlęk M., Król A.

Przemysł Chemiczny

|

2014

|

T. 93, nr 10

1717-1719

PL

Przedstawiono zmodyfikowaną metodę spaleniową sprzężoną z chromatografią jonową, którą wykorzystano do oznaczania zawartości halogenów w biogazie. Opisano etapy optymalizacji i sprawdzenia zarówno metody poboru próbek, jak i metody analitycznej. Oceniono jakość biogazu produkowanego w Polsce.

EN

The modified combustion method conjugated with ion chromatog. was used for detn. of Cl and F contents in the biogas. The biogas flow rate and sampling time were optimized. The method was used for analyzing biogas from wastewater treatment plants, landfills and agricultural biogas plants. The highest Cl and F contents were obsd. in the landfill biogas but they did not exceed the allowable values.

4

Spalanie racjonalną metodą utylizacji odpadów. Część II

Karcz H., Kantorek M., Folga K., Butmankiewicz T., Kozakiewicz A., Kotulski A.

Ciepłownictwo, Ogrzewnictwo, Wentylacja

|

2009

|

R. 40, nr 4

6-9

PL

Opisano technologię KJN do termicznego przekształcania odpadów, która gwarantuje utrzymanie założonych standardów emisyjnych przy wykorzystaniu odpadów jako paliwa alternatywnego w kotłach energetycznych.

EN

The "KJN" technology is described for thermal waste utilisation. The technology ensures assumed emission standards with the waste used as an alternative fuel in the energy boilers.

5

Spalanie racjonalną metodą utylizacji odpadów. Część 1

Karcz H., Kantorek M., Folga K., Butmankiewicz T., Kozakiewicz A., Kotulski A.

Ciepłownictwo, Ogrzewnictwo, Wentylacja

|

2009

|

R. 40, nr 3

3-7

PL

Opisano technologię "KJN" do termicznego przekształcania odpadów, która gwarantuje utrzymanie założonych standardów emisyjnych przy wykorzystaniu odpadów jako paliwa alternatywnego w kotłach energetycznych.

EN

The "KJN" technology is described for thermal waste utilisation. The technology ensures assumed emission standards with the waste used as an alternative fuel in the energy boilers.

6

Kompozyty AIN-AION otrzymywane metodą spalania

Zientara D., Lis J.

Kompozyty

|

2001

|

R. 1, nr 1

93-95

PL

Samorozwijająca się synteza wysokotemperaturowa SHS umożliwia otrzymywanie proszków, związków i faz ceramicznych, aktywnych w toku spiekania. Obserwacje te potwierdzają badania nad syntezą kompozytowych proszków w układzie AlN-AION. Badania strukturalne proszków oraz tworzyw spieczonych skłaniają do wniosku, że przyczyną wysokiej aktywności w spiekaniu proszków otrzymanych techniką SHS są zaburzenia strukturalne i niejednorodności w skali atomowej, będące skutkiem syntezy biegnącej w warunkach wysokich gradientów termicznych i chemicznych.

EN

The pseudobinary system AIN-AI2O3,(AION) contains materials interesting as structure, functional and refractory ceramics (Fig. 1). In the present investigations, the SHS technique was tested in preparation of sinterable oxynitride powders for their following densification into composite AlON-Al2O3 polycrystals. The starting mixtures of aluminium and alumina powders were blended according to an appropriate final AIN-Al2O3 compositions with AIN content above 50 mole %. The powders were SHS processed according described procedure by combustion in nitrogen (Fig. 2). XRD investigations show that the combustion products were composed of AION as a major phase with some amount of AIN. The compositions differ from these expected by the phase diagram, what suggests non-equilibrium character of the SHS products. The powders were hot pressed in nitrogen atmosphere under 25 MPa axial pressure. An example of phase composition of materials before and after densification (composition 70% AIN-30% Al2O3) is presented in Fig. 3. It can be generally noticed, that during hot-temperature densification the SHS powders transform creating new compositions with increased AIN content close to those expected according to the phase diagram. The SHS derived powders had high sinterability. SEM investigations confirmed the materials of high densities with fine grains and uniform phase distribution. The mechanical and refractory properties are promising, they look higher than the analogous for composites prepared using reactive sintering.