Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Słowik, G." wg kryterium: Autor


Wyświetlanie 1-2 z 2
Tytuł:
Paramagnetic Centres in Coal Macerals
Autorzy:
Słowik, G.
Więckowski, A.
Powiązania:
https://bibliotekanauki.pl/articles/1536501.pdf
Data publikacji:
2010-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.66.Hq
76.30.Rn
89.30.ag
Opis:
The electron paramagnetic resonance (EPR) study of coal macerals: exinite, vitrinite and inertinite separated from clarain of the Polish medium-rank coal with carbon content of 85.6 wt% C, were performed. Using the continuous microwave saturation technique (measurements at 223 K and 291 K), as a result of numerical analysis of recorded EPR spectra of exinite, vitrinite and inertinite, their multi-component structure was shown. The EPR spectra of exinite and vitrinite consist of three component lines: one Gaussian G and two Lorentzians: L1 and L3. The EPR spectra of inertinite consist of two narrow lines with Lorentzian line shape L2 and L3. Temperature measurements of studied coal macerals in the range 100-373 K were done. It was evidenced that, in group of paramagnetic centres responsible for Lorentzian L1 component line, paramagnetic centres with thermally excited triplet states (S = 1) exist. Existence of paramagnetic centres with thermally excited triplet states was not observed in inertinite.
Źródło:
Acta Physica Polonica A; 2010, 118, 3; 507-510
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
EPR Evidence for Thermally Excited Triplet States in Exinite, Vitrinite and Inertinite Separated from Bituminous Coal
Autorzy:
Słowik, G. P.
Wojtowicz, W.
Więckowski, A. B.
Powiązania:
https://bibliotekanauki.pl/articles/2043436.pdf
Data publikacji:
2005-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.66.Hq
76.30.Rn
87.64.Hd
Opis:
In this work we have made an electron spin resonance (EPR) study of macerals obtained from the lithotype clarain separated from Polish medium-rank coal (85.6 wt.% C). For three macerals:~exinite, vitrinite, and inertinite, the temperature dependence of intensity of EPR spectra in the temperature range of 100-373 K was investigated. The experimentally obtained EPR spectra of macerals were fitted by curves of the derivatives of the Gaussian and Lorentzian functions. The best fitting was obtained, when the experimental EPR spectra were assumed to be a superposition of three lines, for exinite and vitrinite - a broad Gaussian (G), a broad Lorentzian (L1) and a narrow Lorentzian (L3) line, but for inertinite of two lines - a narrow Lorentzian (L2) and a narrow Lorentzian (L3) line. The computer-assisted fitting has shown that each individual component line has similar values of resonance field, but different linewidths and amplitudes. The temperature dependence of line intensity I of the broad Gaussian (G) and narrow Lorentzian (L2 and L3) lines fulfils the Curie law in the form I=C/T or IT=C, whereas the broad Lorentzian (L1) line does not fulfil the Curie law. In the last case the temperature dependence of the Lorentzian (L1) component was fitted by the relation I=C/T+B/[T(3+exp(J/kT))] or IT=C+B/[3+exp(J/kT))], valid for thermally excited triplet states (S=1). For exinite and vitrinite the curves presenting the temperature dependence of the product IT versus temperature T were resolved into two curves, one for paramagnetic centres in the doublet state (S=1/2), and the other for paramagnetic centres in the thermally excited triplet state (S=1).
Źródło:
Acta Physica Polonica A; 2005, 108, 1; 171-176
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-2 z 2

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies