Thermal, dielectric and barocaloric properties of NH4HSO4 crystallized an from an aqueous solution and the melt
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URI (для ссылок/цитирований):
http://www.sciencedirect.com/science/article/pii/S1293255816308196?via%3Dihubhttps://elib.sfu-kras.ru/handle/2311/70175
Автор:
Михалева, Екатерина Андреевна
Флёров, Игорь Николаевич
Карташев, Андрей Васильевич
Горев, Михаил Васильевич
Богданов, Евгений Витальевич
Бондарев, Виталий Сергеевич
Коллективный автор:
Институт инженерной физики и радиоэлектроники
Кафедра теплофизики
Дата:
2017-05Журнал:
Solid State SciencesКвартиль журнала в Scopus:
Q2Квартиль журнала в Web of Science:
Q2Библиографическое описание:
Михалева, Екатерина Андреевна. Thermal, dielectric and barocaloric properties of NH4HSO4 crystallized an from an aqueous solution and the melt [Текст] / Екатерина Андреевна Михалева, Игорь Николаевич Флёров, Андрей Васильевич Карташев, Михаил Васильевич Горев, Евгений Витальевич Богданов, Виталий Сергеевич Бондарев // Solid State Sciences. — 2017. — Т. 67. — С. 1-7Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.
Аннотация:
A study of heat capacity, thermal dilatation, permittivity, dielectric loops and susceptibility to hydrostatic
pressure was carried out on quasi-ceramic samples of NH4HSO4 obtained from an aqueous solution as
well as the melt. The main parameters of the successive P21/c (T1)4Pc (T2)4P1 phase transitions did
not depend on the method of preparation of the samples, and were close to those determined in previous
studies of single crystal and powder, except for the sign and magnitude of the baric coefficient for T2.
Direct measurements of the pressure effect on the permittivity and thermal properties showed dT2/
dp ¼ 123 K$GPa 1, which is consistent in terms of magnitude and sign with the baric coefficient
evaluated using dilatometric and calorimetric data in the framework of the Clausius-Clapeyron equation.
Thus, the temperature region of the ferroelectric Pc phase existence is extended under pressure. A strong
decrease in the entropy jump at the Pc4P1 transformation with an increase in pressure, and the linear
dependence of T2 on pressure, indicate that an increase in pressure shifts this phase transition towards
the tricritical point on the Tep phase diagram. A significant barocaloric effect was found in the region of
the Pc 4 P1 phase transition.