Membrane phase transition during heating and cooling: molecular insight into reversible melting

2017 ◽  
Vol 47 (2) ◽  
pp. 151-164 ◽  
Author(s):  
Liping Sun ◽  
Rainer A. Böckmann
Keyword(s):  
Phase Transition ◽  
Membrane Phase ◽  
Heating And Cooling ◽  
Reversible Melting ◽  
Insight Into

scholarly journals 2-Chloroalkoxy-Substituted Pentafluorinated Bistolanes as Novel Light-Emitting Liquid Crystals

Crystals ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 195 ◽  
Author(s):  
Shigeyuki Yamada ◽  
Kazuya Miyano ◽  
Tomohiro Agou ◽  
Toshio Kubota ◽  
Tsutomu Konno
Keyword(s):  
Phase Transition ◽  
Liquid Crystals ◽  
Liquid Crystalline ◽  
Valuable Insight ◽  
The Novel ◽  
Light Emitting ◽  
Heating And Cooling ◽  
Chiral Nematic ◽  
Blue Phase ◽  
Insight Into

In this study, we designed and synthesized novel pentafluorinated bistolane derivatives with 2-chloropentyl or 2-chlorohexyl flexible units as novel light-emitting liquid crystals (LELCs). By measuring the phase-transition behaviors, all derivatives were found to display liquid-crystalline (LC) phases during both heating and cooling processes. Among the novel bistolanes, the S- and R-configured derivatives exhibited a chiral nematic (N*) phase with a typical Grandjean optical texture. Interestingly, the chiral derivatives also exhibited a blue phase with a typical platelet texture in a narrow temperature range (2–4 °C). Photophysical measurements revealed that the 2-chloroalkoxy-substituted pentafluorinated bistolanes exhibited intense photoluminescence (PL) both in solution and in crystalline phases. The PL characteristics, especially the maximum PL wavelength, were found to switch sensitively during the heating and cooling cycles depending on the molecular aggregates through the crystal (Cr) ⇄ N* phase transition. The 2-chloroalkoxy flexible units induced dynamic changes in the LC and PL properties, providing valuable insight into the potential of various LELCs as PL sensing materials.

scholarly journals CRITICAL PHENOMENA IN DEEP INELASTIC SCATTERING

2010 ◽  
Vol 25 (31) ◽  
pp. 5667-5682 ◽  
Author(s):  
L. L. JENKOVSZKY ◽  
ANDREA NAGY ◽  
S. M. TROSHIN ◽  
JOLÁN TURÓCI ◽  
N. E. TYURIN
Keyword(s):  
Phase Transition ◽  
Inelastic Scattering ◽  
Deep Inelastic Scattering ◽  
Deeply Virtual Compton Scattering ◽  
Virtual Compton Scattering ◽  
Heavy Ion ◽  
High Energy ◽  
Ion Collisions ◽  
Bjorken X ◽  
Insight Into

Saturation in deep inelastic scattering and deeply virtual Compton scattering is associated with a phase transition between the partonic gas, typical of moderate x and Q2, and partonic fluid appearing at increasing Q2 and decreasing Bjorken x. In this paper we do not intend to propose another parametrization of the structure function; instead we suggest a new insight into the internal structure of the nucleon, as seen in deep inelastic scattering, and its connection with that revealed in high-energy nucleons and heavy-ion collisions.

Vanadium Dioxide Thin Films for Thermo-Optical Switching Applications

2003 ◽  
Vol 785 ◽  
Author(s):  
Lijun Jiang ◽  
William N. Carr
Keyword(s):  
Thin Films ◽  
Phase Transition ◽  
Vanadium Dioxide ◽  
Optical Switching ◽  
Abrupt Change ◽  
Metal Layer ◽  
Heating And Cooling ◽  
Optical Switching Devices ◽  
Lift Off ◽  
Vanadium Dioxide Thin Films

ABSTRACTVanadium dioxide (VO2) thin films were fabricated by e-beam evaporation of vanadium thin films followed by thermal oxidation in oxygen ambient. The properties of the VO2 films were investigated for thermo-optical switching applications. Synthesized VO2 film displays a phase transition at 65 – 68 °C. It exhibits an abrupt change in optical reflectivity over the phase transition temperature range. Results for VO2 on a highly reflective metal layer are strongly dependent on the VO2 thickness. The optical switching has a major hysteresis of about 15 °C between the heating and cooling branches. The evolution of the surface morphology with the oxidation time was studied with a SEM. The VO2 film was patterned on microplatforms by metal lift-off technique. We conclude that the evaporation followed by oxidation is an effective method to produce active VO2 film for thermo-optical switching devices.

The spontaneous polarization as evidence for lithium disordering in LiNbO3

1990 ◽  
Vol 5 (9) ◽  
pp. 1933-1939 ◽  
Author(s):  
Dunbar P. Birnie
Keyword(s):  
Phase Transition ◽  
Spontaneous Polarization ◽  
Paraelectric Phase ◽  
Second Order ◽  
Polarization Data ◽  
Paraelectric Phase Transition ◽  
Microscopic Mechanism ◽  
Second Order Transition ◽  
Displacement Model ◽  
Insight Into

The ferroelectric to paraelectric phase transition in lithium niobate is examined. The present study focuses on the microscopic mechanism for this phase transition. Literature reports that give insight into this mechanism are reviewed. Two alternate mechanisms for this second order transition have been discussed previously. The phase transition has been proposed to occur by either (a) cooperative displacement of Li ions or (b) statistical disordering of Li between two octahedral sites in the structure. The present study develops a general Landau expression for the second order phase transition. The spontaneous polarization of the lattice is used as an indicator of the extent of transformation. Then both displacement and disordering models are explored. These are compared with the observed spontaneous polarization data. It is concluded that the spontaneous polarization data are indicative of a Li disordering model, rather than a Li displacement model.

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