Thermal, ferroelastic, and structural properties near phase transitions of organic–inorganic perovskite type [NH3(CH2)3NH3]CdBr4 crystals

We report the effect of a short-time vacuum annealing (1073 K during 10 minutes) on structural phase transition temperatures and magneto-structural properties of as-quenched ribbons of the Heusler alloy Ni50.6Mn34.5In14.9. This alloy crystallizes in a single phase cubic B2-type austenite with a Curie point of TCA=284 K that with the lowering in temperature transforms into a martensite with TCM185 K. The direct and reverse martensitic phase transition temperatures were MS=257 K, Mf = 221 K, AS = 239 K, and Af = 266 K. After annealing austenite shows the highly ordered L21-type structure while the average chemical composition as well as the structural and magnetic transition temperatures were shifted to Ni50.2Mn34.3In15.5 and MS = 253 K, Mf = 238 K, AS = 257 K, Af = 265 K, ΔT = 13 K, TCA = 299 K and TCM207 K. In the annealed samples the magnetization changes associated to the magnetic and structural transitions are more abrupt and magnetization isotherms in both the austenitic and martensitic existence region show higher initial magnetic susceptibility and faster approach to saturation. Field-cooled hysteresis loops at 10 K were shifted along the negative H-axis for both samples, but a significant anomaly was evident on the left side of the hysteresis loop for as-quenched ribbons.

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Liquid Crystalline Norcholesterylesters: Influence of the Axial Methylgroups on the Phase Transitions and the Cholesteric Helix

Zeitschrift für Naturforschung A ◽

10.1515/zna-1989-1116 ◽

1989 ◽

Vol 44 (11) ◽

pp. 1127-1130 ◽

Cited By ~ 29

Author(s):

H. Stegemeyer ◽

K. Siemensmeyer ◽

W. Sucrow ◽

L. Appel

Keyword(s):

Phase Transition ◽

Phase Transitions ◽

Liquid Crystalline ◽

Helical Structure ◽

Transition Temperatures ◽

Phase Transition Temperatures

Liquid crystalline norcholesteryl anisic esters were prepared in which the methylgroups 19, 21, 27, and 18 are removed successively from the cholestene skeleton. The influence of the axial methylgroups on the phase transition temperatures and the choleric helical structure has been investigated. On heating the 18.19.21.27-tetranorcholesteryl ester, at 155 °C an inversion of the helical screw sense from left to right was observed

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The effect of the photo-stimulated shift of phase transition temperatures in ferroelectrics having phase transitions of different types

Ferroelectrics ◽

10.1080/00150198808235458 ◽

1988 ◽

Vol 83 (1) ◽

pp. 113-118 ◽

Cited By ~ 1

Author(s):

I. P. Raevskii ◽

A. N. Pavlov ◽

M. A. Malitskaya ◽

Yu. M. Popov

Keyword(s):

Phase Transition ◽

Phase Transitions ◽

Transition Temperatures ◽

Phase Transition Temperatures ◽

Different Types

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Dilatometric Study on Phase Transitions of Benzylidene-p-n-hexadecyl /Hexadecyloxy Anilines (5.O16, 5O.O16 and 5.16)

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.181-182.67 ◽

2011 ◽

Vol 181-182 ◽

pp. 67-70

Author(s):

M. Ramakrishna Nanachara Rao ◽

P.V. Datta Prasad ◽

D. Madhavi Latha ◽

V.G.K.M. Pisipati

Keyword(s):

Phase Transition ◽

Schiff Base ◽

Phase Transitions ◽

Liquid Crystalline ◽

The Body ◽

Phase Identification ◽

Transition Temperatures ◽

Phase Transition Temperatures ◽

Characterization Studies ◽

Density Results

Synthesis, characterization and phase transition studies (Dilatometry) have been carried out on three mesomorphic Schiff base compounds viz., N-(p-n-pentyl benzylidene)-p-n-hexadecyloxy aniline, 5.O16, N-(p-n-pentyloxy benzylidene)-p-n-hexadecyloxy aniline 5O.O16 and N-(p-n-pentyl benzylidene)-p-n-hexadecyl aniline, 5.16. The liquid crystalline phase identification and the phase transition temperatures have been carried out using SDTECHS polarising microscope attached with temperature controller with accuracy of ± 0.1 °C and for the conformation of the phase identification and the textures observed are compared with the standard textures. Further, the phase transition temperatures and the corresponding heats of transition across the phase transitions are recorded using DSC (Perkin Elmer). The characterization studies reveal that these compounds exhibit NG, N and A phase variants respectively. The nature of the phase transitions are studied through density results using dilatometric technique. The phase transitions exhibit first order nature in all the cases as expected. The results are discussed in the light of the body of the data available on other Schiff base compounds and on 5O.16.

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Tailoring phase transition temperatures in perovskites via A-site vacancy generation

Dalton Transactions ◽

10.1039/c7dt00352h ◽

2017 ◽

Vol 46 (22) ◽

pp. 7253-7260 ◽

Cited By ~ 3

Author(s):

Thomas A. Whittle ◽

William R. Brant ◽

James R. Hester ◽

Qinfen Gu ◽

Siegbert Schmid

Keyword(s):

Phase Transition ◽

Phase Transitions ◽

Transition Temperatures ◽

Temperature Dependent ◽

Vacancy Generation ◽

Phase Transition Temperatures ◽

A Site ◽

Site Vacancy

Tetragonal strain squared values for each composition across the Sr0.8Ti0.6−xZrxNb0.4O3, 0 ≤ x ≤ 0.6, series were used to accurately determine temperature dependent phase transitions (x = 0.6 is shown).

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Anomalous phase transitions of lead-free piezoelectricxNa0.5Bi0.5TiO3−(1−x)BaTiO3solid solutions with enhanced phase transition temperatures

Physical Review B ◽

10.1103/physrevb.82.224105 ◽

2010 ◽

Vol 82 (22) ◽

Cited By ~ 44

Author(s):

K. Datta ◽

P. A. Thomas ◽

K. Roleder

Keyword(s):

Phase Transition ◽

Phase Transitions ◽

Lead Free ◽

Transition Temperatures ◽

Phase Transition Temperatures

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Triply-responsive OEG-based microgels and hydrogels: Regulation of swelling ratio, volume phase transition temperatures and mechanical properties

Polymer Chemistry ◽

10.1039/d1py00695a ◽

2021 ◽

Author(s):

Dongdong Lu ◽

Mingning Zhu ◽

Jing Jin ◽

Brian R. Saunders

Keyword(s):

Phase Transition ◽

Biomedical Engineering ◽

Volume Phase Transition ◽

Swelling Ratio ◽

Transition Temperatures ◽

Ph Responsive ◽

Network Systems ◽

Volume Phase ◽

Phase Transition Temperatures ◽

Volume Swelling

Thermally- and pH-responsive microgels (MGs) and hydrogels are fascinating network systems that have been applied in biomedical engineering and sensing. The volume-swelling ratio (Q) and the volume-phase transition temperatures (VPTTs)...

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