Observation of multiple phase transitions in some even n-alkanes using a high resolution and super-sensitive DSC

Shaolan Wang; Ken-Ichi Tozaki; Hideko Hayashi; Hideaki Inaba; Hiroko Yamamoto

doi:10.1016/j.tca.2006.06.022

Observation of multiple phase transitions in n-C22H46 using a high resolution and super-sensitive DSC

Thermochimica Acta ◽

10.1016/s0040-6031(03)00312-5 ◽

2003 ◽

Vol 408 (1-2) ◽

pp. 31-38 ◽

Cited By ~ 31

Author(s):

Shaolan Wang ◽

Ken-ichi Tozaki ◽

Hideko Hayashi ◽

Shotaro Hosaka ◽

Hideaki Inaba

Keyword(s):

Phase Transitions ◽

High Resolution ◽

Multiple Phase

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Multiple phase transitions investigated by high-speed TEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100175880 ◽

1990 ◽

Vol 48 (4) ◽

pp. 550-551

Author(s):

Oleg Bostanjoglo ◽

Peter Thomsen-Schmidt

Keyword(s):

Phase Transitions ◽

High Speed ◽

Short Exposure ◽

Semiconductor Film ◽

Time Resolved ◽

Short Exposure Time ◽

Multiple Phase ◽

Model Substance ◽

History Of ◽

Electron Image

Thin GexTe1-x (x = 0.15-0.8) were studied as a model substance of a composite semiconductor film, in addition being of interest for optical storage material. Two complementary modes of time-resolved TEM were used to trace the phase transitions, induced by an attached Q-switched (50 ns FWHM) and frequency doubled (532 nm) Nd:YAG laser. The laser radiation was focused onto the specimen within the TEM to a 20 μm spot (FWHM). Discrete intermediate states were visualized by short-exposure time doubleframe imaging /1,2/. The full history of a transformation was gained by tracking the electron image intensity with photomultiplier and storage oscilloscopes (space/time resolution 100 nm/3 ns) /3/. In order to avoid radiation damage by the probing electron beam to detector and specimen, the beam is pulsed in this continuous mode of time-resolved TEM,too.Short events ( <2 μs) are followed by illuminating with an extended single electron pulse (fig. 1c)

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HIGH RESOLUTION CALORIMETRIC STUDIES AT PHASE TRANSITIONS OF ALKYLCYANOBIPHENYL LIQUID CRYSTALS CONFINED TO SUBMICRON SIZE CYLINDRICAL CAVITIES

International Journal of Modern Physics B ◽

10.1142/s0217979295000884 ◽

1995 ◽

Vol 09 (18n19) ◽

pp. 2247-2283 ◽

Cited By ~ 15

Author(s):

DANIELE FINOTELLO ◽

GERMANO S. IANNACCHIONE

Keyword(s):

Phase Transitions ◽

Liquid Crystals ◽

High Resolution ◽

Specific Heat ◽

Pore Wall ◽

Isotropic Phase ◽

First Order ◽

Smectic A ◽

Nematic Director ◽

Scalar Order Parameter

We review results of a high resolution systematic study of the specific heat for alkyl-cyanobiphenyl liquid crystals confined to the 0.2µm diameter cylindrical pores Anopore membranes. The nematic director alignment at the pore wall is varied from homeotropic to tangential by pore surface treatment. Several phenomena are uncovered by these studies which probed the weakly first order nematic to isotropic, the continuous smectic-A to nematic and the first order smectic-A to isotropic phase transitions. The specific heat is strongly dependent on the nematic director configuration, and confinement effects are remarkably distinct according to the order of the phase transition. The influence of elastic distortions and surface ordering and disordering effects are evident. Despite considerable departures from bulk behavior with regards to specific heat peaks size, rounding and width, and transition temperature shifts, a bulk-like critical behavior appears to be retained. The formation of smectic translational order within the pores is hindered for those liquid crystals that also possess a nematic phase. The average scalar order parameter temperature dependence is extracted from the specific heat results using a simplified Landau-de Gennes type of model, and is shown to be consistent with nuclear magnetic resonance results.

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Hysteresis Abated P2-type NaCoO2 Cathode Reveals Highly Reversible Multiple Phase Transitions for High-Rate Sodium-ion Batteries

Sustainable Energy & Fuels ◽

10.1039/d1se00490e ◽

2021 ◽

Author(s):

VENKATA RAMI REDDY BODDU ◽

Manikandan Palanisamy ◽

Lichchhavi Sinha ◽

Subhash Yadav ◽

Vilas Pol ◽

...

Keyword(s):

Phase Transitions ◽

Discharge Rate ◽

Cycle Life ◽

Sodium Ion ◽

High Rate ◽

Sodium Ion Batteries ◽

Long Cycle Life ◽

Multiple Phase ◽

Ion Intercalation ◽

Charge Discharge

Despite multiple phase transitions occur during Na+ ion intercalation and deintercalation, enhanced charge-discharge rate, and long cycle life are achieved to hexagonal shaped P2-type NaCoO2 cathode for sodium-ion batteries (SIBs)....

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A Kinetic Model of Multiple Phase Transitions in Ice

10.1063/1.1483525 ◽

2002 ◽

Author(s):

Gloria Cruz León

Keyword(s):

Phase Transitions ◽

Kinetic Model ◽

Multiple Phase

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MODELLING OF MULTIPLE PHASE TRANSITIONS UNDER SHOCK IN ICE

10.1063/1.3295020 ◽

2009 ◽

Cited By ~ 2

Author(s):

David Hebert ◽

Isabelle Bertron ◽

Olivier Heuzé ◽

Mark Elert ◽

Michael D. Furnish ◽

...

Keyword(s):

Phase Transitions ◽

Multiple Phase

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The structures of marialite (Me6) and meionite (Me93) in space groups P42/n and I4/m, and the absence of phase transitions in the scapolite series

Powder Diffraction ◽

10.1154/1.3582802 ◽

2011 ◽

Vol 26 (2) ◽

pp. 119-125 ◽

Cited By ~ 1

Author(s):

Sytle M. Antao ◽

Ishmael Hassan

Keyword(s):

Phase Transitions ◽

High Resolution ◽

Crystal Structures ◽

Unit Cell ◽

X Ray Diffraction ◽

Unit Cell Parameters ◽

X Ray ◽

Space Groups ◽

Cell Parameters ◽

The Mean

The crystal structures of marialite (Me6) from Badakhshan, Afghanistan and meionite (Me93) from Mt. Vesuvius, Italy were obtained using synchrotron high-resolution powder X-ray diffraction (HRPXRD) data and Rietveld structure refinements. Their structures were refined in space groups I4/m and P42/n, and similar results were obtained. The Me6 sample has a formula Ca0.24Na3.37K0.24[Al3.16Si8.84O24]Cl0.84(CO3)0.15, and its unit-cell parameters are a=12.047555(7), c=7.563210(6) Å, and V=1097.751(1) Å3. The average ⟨T1-O⟩ distances are 1.599(1) Å in I4/m and 1.600(2) Å in P42/n, indicating that the T1 site contains only Si atoms. In P42/n, the average distances of ⟨T2-O⟩=1.655(2) and ⟨T3-O⟩=1.664(2) Å are distinct and are not equal to each other. However, the mean ⟨T2,3-O⟩=1.659(2) Å in P42/n and is identical to the ⟨T2′-O⟩=1.659(1) Å in I4/m. The ⟨M-O⟩ [7]=2.754(1) Å (M site is coordinated to seven framework O atoms) and M-A=2.914(1) Å; these distances are identical in both space groups. The Me93 sample has a formula of Na0.29Ca3.76[Al5.54Si6.46O24]Cl0.05(SO4)0.02(CO3)0.93, and its unit-cell parameters are a=12.19882(1), c=7.576954(8) Å, and V=1127.535(2) Å3. A similar examination of the Me93 sample also shows that both space groups give similar results; however, the C–O distance is more reasonable in P42/n than in I4/m. Refining the scapolite structure near Me0 or Me100 in I4/m forces the T2 and T3 sites (both with multiplicity 8 in P42/n) to be equivalent and form the T2′ site (with multiplicity 16 in I4/m), but ⟨T2-O⟩ is not equal to ⟨T3-O⟩ in P42/n. Using different space groups for different regions across the series implies phase transitions, which do not occur in the scapolite series.

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