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Volume 47 (2020)
- Issue 4 Pages 129-
- Issue 3 Pages 83-
- Issue 2 Pages 51-
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Volume 47, Issue 2
Displaying 1-6 of 6 articles from this issue
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JSCTA Award 2019
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Hitoshi Matsuki2020 Volume 47 Issue 2 Pages 51-57
Published: April 25, 2020
Released on J-STAGE: November 22, 2022
JOURNAL FREE ACCESSPhospholipid bilayer membranes undergo structural changes called phase transitions in response to various external environmental factors. They exhibit markedly complicated phase behavior due to the nonhomogeneous structures. We have investigated the bilayer phase transitions of various phospholipids with different molecular structures to elucidate the environmental adaptation of biological membranes. The constructed thermodynamic phase diagrams of the phospholipid bilayer membranes have revealed the correlation between the lipid molecular structures and the thermotropic and barotropic bilayer phase behavior. In this review, several types of bilayer phase behavior of representative glycerophospholipids contained in biological membranes, saturated diacyl-posphatidylcholines (PCs), phosphatidylethanolamines (PEs) and -phosphatidylglycerols (PGs), are explained, and subsequently our lipid membrane studies based on the bilayer phase diagrams, formation of nonbilayer phases (chain interdigitation for saturated diacylPCs and inverted hexagonal transformation for unsaturated diacyl-PEs) and fluorescence imaging of bilayer packing for saturated diacyl-PCs, are introduced.View full abstractDownload PDF (2926K)
JSCTA Research Encouragement Award 2019
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Yoshitomo Furushima2020 Volume 47 Issue 2 Pages 58-63
Published: April 25, 2020
Released on J-STAGE: November 22, 2022
JOURNAL FREE ACCESSFast scanning chip calorimetry (FSC) experiments were carried out in a wide range of rates of temperature for semi-crystalline polymers (i.e poly(butylene terephthalate (PBT), polyphenylene sulfide, and isotactic polypropylene) to investigate the kinetics of non-isothermal crystallization, isothermal crystallization, and melting. First, the heat of fusion after cooling was discussed for the quantitative understanding of melt-crystallization on cooling. Despite polymer species, crystallinity decreases with increasing cooling rate. The cooling rate dependence of crystallinity showed two distinctive areas. The scanning rate dependence of enthalpy of melt crystallization, cold crystallization and recrystallization obtained from FSC are quantitatively explained on the basis of Ozawa's method. For isothermal kinetics, FSC allows to obtain the annealing-temperature dependence of crystallization half-time in a wide range of the supercooling without any unwanted nucleation or crystallization during cooling. A bimodal curve with two minima was observed for PBT and PBT with 0.1 wt% talc.View full abstractDownload PDF (1834K)
Review
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Takahiro Ueda2020 Volume 47 Issue 2 Pages 64-69
Published: April 25, 2020
Released on J-STAGE: November 22, 2022
JOURNAL FREE ACCESSThe nanometer-sized space formed in the porous material gives rise to a significant effect on the physicochemical properties of the condensed matter confined therein. It is well-known as the “confinement effect”, and it has been extensively interested in the relation between the size of the space and the structure and physical properties of the confined molecular assembly. We found that the adsorbed benzene molecules show two phase transitions in an isoreticular metal-organic framework-1 (IRMOF-1). Solid-state NMR and molecular dynamics simulation revealed that the molecular reorientation and intra-cavity migration of benzene take place in the two kinds of cavity in IRMOF-1 in the low and intermediate temperature phases. In the intermediate temperature phase, dynamic disorder of benzene occurs in the smaller cavities, accompanying partial melting of benzene in the smaller cavities. In contrast, in the high temperature phase the translational diffusion of benzene takes place over all the cavities. This fact suggests the phase transition is closely concerned with melting of the confined benzene. In this review, we describe the unique structure and physical properties of molecular assembly adsorbed into IRMOF-1 through the molecular motion and phase transition of benzene.View full abstractDownload PDF (2150K) -
Yoshiro Yamada2020 Volume 47 Issue 2 Pages 70-75
Published: April 25, 2020
Released on J-STAGE: November 22, 2022
JOURNAL FREE ACCESSThe unit for thermodynamic temperature in the International System of Units (SI), kelvin, was redefined in May 2019. In this article, an overview is given of the redefinition, its background and implications to future thermometry. The redefinition has no immediate impact: the temperature that we measure daily is on the International Temperature Scale of 1990 (ITS-90), which has its own definition independent from the definition of the unit kelvin. The efforts within the international metrology community towards the redefinition led to improvement in primary thermometry, and the difference between thermodynamic temperature T and ITS-90 temperature T90 has become available with improved accuracy. This will enable converting T90, obtained by secondary thermometers, to T. In Japan, traceability for radiation thermometers in high-temperature range has already been implemented utilizing primary standards of high-temperature fixed points with assigned thermodynamic temperature, and the industry now has access to thermodynamic temperature above 1000 ºC.View full abstractDownload PDF (2029K)
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2020 Volume 47 Issue 2 Pages 76-77
Published: April 25, 2020
Released on J-STAGE: November 22, 2022
JOURNAL FREE ACCESSDownload PDF (577K)
Applied Research of Thermal Analysis
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Susumu Ito, Eita Shimoda, Hidehiro Takahashi, Nobuaki Okubo2020 Volume 47 Issue 2 Pages 78-79
Published: April 25, 2020
Released on J-STAGE: November 22, 2022
JOURNAL FREE ACCESSDownload PDF (782K)
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