THERMODYNAMIC MODEL OF CaO-SiO2 GLASSES

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216275%3A25310%2F20%3A39916405" target="_blank" >RIV/00216275:25310/20:39916405 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/60461373:22310/20:43921660

Výsledek na webu

<a href="https://www.ceramics-silikaty.cz/index.php?page=cs_detail_doi&id=1301" target="_blank" >https://www.ceramics-silikaty.cz/index.php?page=cs_detail_doi&id=1301</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.13168/cs.2019.0049" target="_blank" >10.13168/cs.2019.0049</a>

Jazyk výsledku

angličtina

Název v původním jazyce

THERMODYNAMIC MODEL OF CaO-SiO2 GLASSES

Popis výsledku v původním jazyce

The CaO-SiO2 glass forming system is a typical example of a situation when the Shakhmatkin and Vedishcheva thermodynamic model cannot explain the experimentally determined Q-units distribution. As the system components are determined as stable crystalline phases found in the equilibrium phase diagram, the reason of the model failure is the missing system component representing the Q(3) structural unit. We suggested a solution to the problem by adding an artificial CaO center dot 2SiO(2) component and we proposed a method of estimating the Gibbs energy of this component. The method is based on the linear relationship found between the reaction Gibbs energy of the formation of the system components representing the different Qn units (n = 3, 2, 1, 0) divided by the number of non-bridging oxygen atoms in this particular component (i.e., 4-n) on one side and the n value on the other side. The method was qualified by the good coincidence of the model results with the MAS NMR experimentally determined Q-distribution. Moreover, the estimated value of Gibbs energy practically coincides with the optimised value obtained by minimising the sum of the squares of the d eviations between the experimental and calculated Q-distribution with respect to the molar Gibbs energy of CaO center dot 2SiO(2).

Název v anglickém jazyce

THERMODYNAMIC MODEL OF CaO-SiO2 GLASSES

Popis výsledku anglicky

The CaO-SiO2 glass forming system is a typical example of a situation when the Shakhmatkin and Vedishcheva thermodynamic model cannot explain the experimentally determined Q-units distribution. As the system components are determined as stable crystalline phases found in the equilibrium phase diagram, the reason of the model failure is the missing system component representing the Q(3) structural unit. We suggested a solution to the problem by adding an artificial CaO center dot 2SiO(2) component and we proposed a method of estimating the Gibbs energy of this component. The method is based on the linear relationship found between the reaction Gibbs energy of the formation of the system components representing the different Qn units (n = 3, 2, 1, 0) divided by the number of non-bridging oxygen atoms in this particular component (i.e., 4-n) on one side and the n value on the other side. The method was qualified by the good coincidence of the model results with the MAS NMR experimentally determined Q-distribution. Moreover, the estimated value of Gibbs energy practically coincides with the optimised value obtained by minimising the sum of the squares of the d eviations between the experimental and calculated Q-distribution with respect to the molar Gibbs energy of CaO center dot 2SiO(2).

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20501 - Materials engineering

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název periodika

Ceramics-Silikaty

ISSN

0862-5468

e-ISSN

—

Svazek periodika

64

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

CZ - Česká republika

Počet stran výsledku

5

Strana od-do

63-67

Kód UT WoS článku

000508638600007

EID výsledku v databázi Scopus

2-s2.0-85082077222