| 高分子 Vol.63 No.7 |
| >>Chinese | >>English | >>Japanese | >>Korean |
特集 高分子構造解析の原点を知る －世界結晶年2014 を記念して－
|
| 展望 COVER STORY: Highlight Reviews |
| 結晶研究の先達－寺田寅彦と中谷宇吉郎 Pioneer of Crystallography-Drs. Torahiko Terada and Ukichiro Nakaya |
神田 健三 Kenzo KANDA |
| ＜要旨＞ 世界結晶年2014にあたり、結晶学に世界的に貢献した日本人、寺田寅彦と中谷宇吉郎について紹介する。寺田はX線結晶学の黎明期に実験に取り組み、NatureにLetterを2回掲載し、ブラッグとほぼ同等の結果を得た。また、寺田の薫陶を受けた中谷は、世界初の人工雪作りに成功し、雪の結晶形と成長時の条件の関係を明らかにした。 Keywords: IYCr2014 / X-Ray Crystallography / Torahiko Terada / Ukichiro Nakaya / Snow Crystall |
| ページトップへ▲ |
| 高分子結晶の特異性 Characteristics of Polymer Crystals |
梶 慶輔 Keisuke KAJI |
| ＜要旨＞線状高分子結晶の特徴と重要な物性に言及した後、工業的に重要な融体結晶化機構の新しい概念を解説する。融体は結晶化誘導期に伸長鎖セグメントの配向揺らぎによるミクロ相分離を起こすが、それには二つのタイプがある。高温側のバイノダル型では通常の球晶が生成するが、低温側のスピノダル型では多数の微小球晶が発生する。材料の高性能化には後者のスピノダル結晶化が重要である。 Keywords: Polymer Crystals / Crystallization Mechanism / Induction Period / Phase Separation / Binodal Crystallization / Spinpdal Crystallization / High Performance Materials |
| ページトップへ▲ |
| 電子顕微鏡と高分子結晶 Polymer Crystals and Electron Microscopy |
磯田 正二 Seiji ISODA |
| ＜要旨＞高分子のミクロ構造の多様性の解明のために、とくに単結晶の発見以来、電子顕微鏡は高分子材料の解析方法として高分子研究の進展に大きな貢献をしてきた。電子顕微鏡と高分子結晶とのかかわり合いを解説し、その歴史的な基盤の概説と最近の洗練されたさまざまな電子顕微鏡法による研究成果、およびこれから期待される新しい研究展開について述べる。 Keywords: Polymer Crystals / Electron Microscopy |
| ページトップへ▲ |
| トピックス COVER STORY: Topics and Products |
| 超高強度高分子の結晶格子の直接観察 Direct Observation of Crystalline Lattices in an Ultrahigh Strength Polymer |
村瀬 浩貴 Hiroki MURASE |
| ＜要旨＞ PBO fiber is the strongest organic fiber in the world. Direct observation of crystalline lattices was investigated in the PBO fiber using transmission electron microscopy（TEM）. The density fluctuations giving a four-point type scattering on small-angle X-ray scattering（SAXS） have attracted the attention of many researchers. The combination of lattice images and defocused images elucidated the origin of the density fluctuations. The high density regions show a positional coincidence with the lattice fringes in the TEM micrographs and this highly suggests that the intriguing SAXS pattern originates from the density difference between the crystalline regions and the non-crystalline disordered regions. Keywords: Crystalline Lattice / TEM / Lattice Image / Deforcused Image |
| ページトップへ▲ |
| 広角中性子回折データに基づく高分子結晶構造解析の最先端 Most Advanced Structure Analysis of Polymer Crystals Based on Wide-Angle Neutron Diffraction Data |
田代 孝二 Kohji TASHIRO |
| ＜要旨＞ The most advanced state of crystal structure analysis of polymer substances has been reviewed on the basis of wide-angle neutron diffraction （WAND） data. Several case studies have been used to extract the hydrogen atomic positions in the unit cell, which are indispensable in the most reliable theoretical estimation of ultimate mechanical properties of polymer crystals as a guiding principle to develop the polymer materials with more excellent mechanical properties. These 2D WAND data were collected using a BIX-3 system of JRR-3 and also an i-BIX system of J-PARC, Tokai-mura, Japan. The organized combination of WAND data with high-energy synchrotron wide-angle X-ray diffraction data has been found to give the most accurate crystal structure information as exemplified for the cases of polyoxymethylene and poly（L-lactic acid）. Another utilization of neutron scattering is also pointed out for the studies of molecular motions in the phase transitions, chain aggregation state in the melt, and so on. Keywords: Wide-Angle Neutron Diffraction / Crystal Structure Analysis / Hydrogen Atomic Positions / Ultimate Mechanical Property / High-Energy Synchrotron Wide-Angle X-Ray Diffraction / Polyethylene / Polyoxymethylene / Poly（L-lactic acid） |
| ページトップへ▲ |
| シグナル伝達を制御する微弱な相互作用をX線結晶解析によってとらえる Capturing Low-Affinity Protein-Protein Interactions in the Regulation of Cellular Signal Transduction by X-Ray Crystallography |
禾 晃和 Terukazu NOGI |
| ＜要旨＞ Most protein molecules are localized at particular compartments within the cell and their mobilities are more or less restricted due to the molecular crowding effects. For instance, membrane proteins can diffuse only two-dimensionally because they are confined in the lipid bilayer. It is therefore presumed that even low-affinity protein-protein interactions should be effective for regulating physiological functions of membrane proteins whereas they cannot be detected by biochemical binding assays using solubilized protein molecules or fragments. In contrast, X-ray crystallography can be applied to the detection of such weak interactions in some cases since functional oligomeric assemblies or physiologically-relevant superstructures are sometimes reproduced in the crystal packing. The significances of crystal packing interactions can be examined by combining a wide range of structural biology methods including nuclear magnetic resonance, small-angle X-ray scattering, electron and light microscopy. In general, such multidisciplinary approaches are accepted as “integrated structural biology” and are expected to elucidate structures and dynamics of protein molecules in action. Keywords: X-Ray Crystallography / Signal Transduction / Membrane Protein / Protein-Protein Interactions / Integrated Structural Biology |
| ページトップへ▲ |
| グローイングポリマー Polymer Science and I: A Personal Account |
| 好きなこと What I like |
押村 美幸 Miyuki OSHIMURA |
| ＜要旨＞ From when I was assigned to the laboratory until now, my motivation for my study is a “what I like” approach. Spreading my interest, I’ve been broadening my study areas, luckily. |
| ページトップへ▲ |
| 高分子科学最近の進歩 Front-Line Polymer Science |
| 円偏光増幅フォトニクス Gigantic Enhanced Chiral Photonics |
藤木 道也 Michiya FUJIKI |
| ＜要旨＞ Circularly polarized electromagnetic wave is currently utilized in several mobile telecommunication systems in 1-12 GHz region, including ETC, GPS, and satellite broadcasting. Recently, several optically active materials and devices have been realized directed toward high-performance circularly polarized absorption, reflectance, and emission modes in UV-visible region. The present review highlights recent developments in gigantic enhanced chiroptical materials and devices operating at UV-visible region. Moreover, this review showed uniqueness of circularly polarized light in the animate nature. Understanding modern chiral photonics and the animated nature are promising in a wide range of circularly-polarized oriented applications, including white-light backlight, laser, nonlinear optics, biosensors, FET, controlled plant growing, elucidation of photosynthesis mechanism, practical absolute chiral photosynthesis, and a possible answer to homochirality question on Earth. Keywords: Circular Dichroism / Circularly Polarized Luminescence / Animated Nature / Telecommunication / Chiral Photonics / Absolute Asymmetric Synthesis / Homochirality / Structural Coloring / Chirality / Helicity |
| ページトップへ▲ |
| Copyright(C) 2014 The Society of Polymer Science, Japan All Rights Reserved. |