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981.
982.
T Hamada M Morita M Miyakawa R Sugimoto A Hatanaka MC Vestergaard M Takagi 《Journal of the American Chemical Society》2012,134(34):13990-13996
It is important that we understand the physical, chemical, and biological mechanisms that govern the interaction between nanoparticles (NPs) and heterogeneous cellular surfaces because of the possible cytotoxicity of engineered nanomaterials. In this study, we investigated the lateral localization of nano/microparticles within a biomimetic heterogeneous membrane interface using cell-sized two-phase liposomes. We found that lateral heterogeneity in the membrane mediates the partitioning of nano/microparticles in a size-dependent manner: small particles with a diameter of ≤200 nm were localized in an ordered phase, whereas large particles preferred a fluidic disordered phase. This partitioning behavior was verified by temperature-controlled membrane miscibility transition and laser-trapping of associated particles. In terms of the membrane elastic energy, we present a physical model that explains this localization preference of nano/microparticles. The calculated threshold diameter of particles that separates the particle-partitioning phase was 260 nm, which is in close agreement with our observation (200 nm). These findings may lead to a better understanding of the basic mechanisms that underlie the association of nanomaterials within a cell surface. 相似文献
983.
Yuko Takeoka Mitsuyasu Kawahara Masahiro Rikukawa 《Journal of Physics and Chemistry of Solids》2012,73(11):1401-1403
Novel organic–inorganic hybrid compounds, C16H44N4Pb3I10 and C14H34N2Pb2I6, were synthesized by solvent diffusion recrystallization from the dimethylsulfoxide solution containing PbI2 and gemini ammonium surfactants with different head groups. The results of single crystal X-ray structural analysis showed that the inorganic region of C16H44N4Pb3I10 has quasi one-dimensional chains of [Pb3I10]4? units, whereas that of C12H30N2Pb2I6 has one-dimensional chains of face-sharing PbI6 octahedra. The absorption and fluorescence spectra of these compounds also indicate the formation of one-dimensional inorganic chains and quantum-confined structures. 相似文献
984.
Masahiro Ikeda 《Nonlinear Analysis: Theory, Methods & Applications》2012,75(1):211-225
We study the scattering problem for the Hartree-Fock equation
(HRF) 相似文献
985.
Hidenori Hiramatsu Toshio Kamiya Masahiro Hirano Hideo Hosono 《Physica C: Superconductivity and its Applications》2009,469(9-12):657-666
FeAs-based layered superconductors such as F-doped LaFeAsO have recently been investigated intensively because of their high superconducting transition temperatures. Epitaxial films of these compounds are important to examine their intrinsic materials properties as well as to transfer them to device applications. In this review, we first present our research route from transparent p-type oxides semiconductors to the Fe-based superconductors. Then we review growth of epitaxial thin films for the layered oxychalcogenides and oxypnictides. Reactive solid-phase epitaxy technique was inevitable to prepare epitaxial thin films of the oxychalcogenides and Zn-based oxypnictides. On the other hand, epitaxial thin films of Mn-based oxypnictides were grown by standard pulsed laser deposition. These techniques, however, did not grow epitaxial thin films for LaFeAsO. Thus, we developed a modified pulsed laser deposition process and succeeded in obtaining epitaxial thin films of FeAs-based superconductors, LaFeAsO and cobalt-doped SrFe2As2. 相似文献
986.
Stefan T. Norberg Stefan Hoffmann Masahiro Yoshimura Nobuo Ishizawa 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(3):i35-i38
The compound Al6Ti2O13 (hexaaluminium dititanium tridecaoxide) has been synthesized using an arc‐imaging furnace, which allows fast cooling of melted oxides. The structure consists of infinite double chains of polyhedra running along the c axis. These chains are built up by four kinds of strongly distorted oxygen octahedra randomly occupied by either Ti or Al (point symmetry m or m2m), and by trigonal bipyramids exclusively occupied by Al (point symmetry m2m). 相似文献
987.
Masahiro Okada 《Tetrahedron》2009,65(10):2136-3297
In the post-genomic era, the biological activity of endogenous metabolites can be linked to genomic information via its target protein. Consequently, studies concerned with the identification of endogenous bioactive metabolites from model organisms should be undertaken. (R)-Eucomic acid (1) was identified as an endogenous metabolite concerning leaf movement in the model legume, Lotus japonicus. Absolute stereochemistry was investigated by comparison of physical characteristics of natural and synthetic enantiomers of 1. Identification of endogenous metabolites in a model legume would be particularly advantageous for further studies on the chemical biology of this biologically intriguing phenomenon. 相似文献
988.
Copper(I) coordination complexes of the anionic fluorinated ligand, hydrotris(3-trifluoromethyl-5-methyl-1-pyrazolyl)borate (L0f−), i.e. the copper(I) carbonyl complex, [CuI(L0f)(CO)] (1), the copper(I) triphenylphosphine complex, [CuI(L0f)(PPh3)] (2), the copper(I) acetonitrile complex, [CuI(L0f)(NCMe)] (3), and the corresponding copper(I) triphenylphosphine complex with hydrotris(3,5-diisopropyl-1-pyrazolyl)-borate anion (L1−), i.e. [CuI(L1)(PPh3)] (4), were synthesized in order to investigate the influence of the electron-withdrawing groups on the pyrazolyl rings. The structures of complexes 1, 2, and 4 were determined by X-ray crystallography. While X-ray crystallography did not show definitive trends in terms of copper(I) atom geometry, the clear influence of the electronic structure of the pyrazolyl rings is observed by spectroscopic techniques, namely, IR and multinuclear NMR spectroscopy. Finally, the relative stability of the copper(I) complexes is discussed. 相似文献
989.
Most of the photopatterning materials based on epoxy resins utilize photoacid generators (PAGs), which generate superacids as catalysts. They have been used for high aspect ratio photoresists in the fabrication of MEMS devices. However, there is a drawback, in that the acidic species from PAGs will induce metal corrosion. One of the approaches to overcome this problem is the use of photobase generators (PBGs) because organic bases would induce no corrosion. Although there have been many previous investigations of PBGs, only a few articles have mentioned photoreactive materials relying on PBGs because of their low photosensitivity. We report here highly sensitive photopatterning materials comprising PBGs and an epoxy resin bearing carboxylic acid groups. As a result, the photopatterning materials showed higher photosensitivity than conventional epoxy resin systems. We obtained high‐photosensitivity (up to 900 mJ/cm2), high‐resolution (10‐μm line‐and‐space) patterning materials in films, 10 μm in thickness. 相似文献
990.
Rui Umeda Yuji Shimizu Yuta Ida Masahiro Ikeshita Shuichi Suzuki Takeshi Naota Yutaka Nishiyama 《Tetrahedron letters》2019,60(2):183-186
π-Extended oxepins 1 and dimer 8 were synthesized by the benzannulation of the corresponding asymmetric diarylacetylene derivatives and 2-(phenylethynyl)benzaldehyde followed by the Cu-catalyzed intramolecular cyclization. The optical properties of the π-extended oxepins 1 and 8 are also investigated. 相似文献