Thermal behaviour of pyrope at 1000 and 1100 degrees C: mechanism of Fe2+ oxidation and decomposition model

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15410%2F03%3A00001545" target="_blank" >RIV/61989592:15410/03:00001545 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68145535:_____/03:15033061

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Thermal behaviour of pyrope at 1000 and 1100 degrees C: mechanism of Fe2+ oxidation and decomposition model

Popis výsledku v původním jazyce

The mechanism of thermally induced oxidation of Fe2+ from natural pyrope has been studied at 1000 and 1100 degreesC using Fe-57 Mossbauer spectroscopy in conjunction with XRD, XRF, AFM, QELS, TG, DTA and electron microprobe analyses. At 1000 degreesC, the non-destructive oxidation of Fe2+ in air includes the partial stabilization of Fe3+ in the dodecahedral 24c position of the garnet structure and the simultaneous formation of hematite particles (15-20 nm). The incorporation of the magnesium ions to thehematite structure results in the suppression of the Morin transition temperature to below 20 K. The general garnet structure is preserved during the redox process at 1000 degreesC, in accordance with XRD and DTA data. At 1100 degreesC, however, oxidative conversion of pyrope to the mixed magnesium aluminium iron oxide, Fe-orthoenstatite and cristoballite was observed. During this destructive decomposition, Fe2+ is predominantly oxidized and incorporated into the spinel structure of Mg(

Název v anglickém jazyce

Thermal behaviour of pyrope at 1000 and 1100 degrees C: mechanism of Fe2+ oxidation and decomposition model

Popis výsledku anglicky

The mechanism of thermally induced oxidation of Fe2+ from natural pyrope has been studied at 1000 and 1100 degreesC using Fe-57 Mossbauer spectroscopy in conjunction with XRD, XRF, AFM, QELS, TG, DTA and electron microprobe analyses. At 1000 degreesC, the non-destructive oxidation of Fe2+ in air includes the partial stabilization of Fe3+ in the dodecahedral 24c position of the garnet structure and the simultaneous formation of hematite particles (15-20 nm). The incorporation of the magnesium ions to thehematite structure results in the suppression of the Morin transition temperature to below 20 K. The general garnet structure is preserved during the redox process at 1000 degreesC, in accordance with XRD and DTA data. At 1100 degreesC, however, oxidative conversion of pyrope to the mixed magnesium aluminium iron oxide, Fe-orthoenstatite and cristoballite was observed. During this destructive decomposition, Fe2+ is predominantly oxidized and incorporated into the spinel structure of Mg(

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

BM - Fyzika pevných látek a magnetismus

OECD FORD obor

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Projekt

<a href="/cs/project/GA202%2F00%2F0982" target="_blank" >GA202/00/0982: Studium vzniku a transformací různých forem oxidu železitého při tepelném rozkladu solí železa</a><br>

Návaznosti

Z - Vyzkumny zamer (s odkazem do CEZ)

Rok uplatnění

2003

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

PHYSICS AND CHEMISTRY OF MINERALS

ISSN

0342-1791

e-ISSN

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Svazek periodika

30

Číslo periodika v rámci svazku

10

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

8

Strana od-do

620-627

Kód UT WoS článku

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EID výsledku v databázi Scopus

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