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Journal
2015 | 60 | 3 | 389-393
Article title

Determination of the fraction of paramagnetic centers not-fulfilling the Curie law in coal macerals by the two-temperature EPR measurement method

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EN
Abstracts
EN
Two-temperature electron paramagnetic resonance (EPR) measurements, applied to determine the relative contributions of paramagnetic centers – fulfilling and not-fulfilling the Curie law, were carried out. The measurements were made on the macerals – exinite and vitrinite, separated from clarain of the Polish medium-rank coal (85.6 wt% C). The two-temperature EPR measurements, presented in this work, were performed respectively, at temperatures: T1 = 293 K and T2 = 173 K for exinite, and T1 = 293 K and T2 = 153 K for vitrinite. The relative contributions X of spins not-fulfilling the Curie law present in the studied macerals were calculated. A comparison of different methods of calculating the relative contributions of paramagnetic centers – fulfilling and not-fulfilling the Curie law, present in exinite and vitrinite studied by EPR was made.
Publisher
Journal
Year
Volume
60
Issue
3
Pages
389-393
Physical description
Dates
published
1 - 7 - 2015
received
1 - 10 - 2014
accepted
30 - 1 - 2015
online
6 - 8 - 2015
References
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Document Type
Publication order reference
YADDA identifier
bwmeta1.element.-psjd-doi-10_1515_nuka-2015-0069
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