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81.
Ishii A Kawai T Tekura K Oshida H Nakayama J 《Angewandte Chemie (International ed. in English)》2001,40(10):1924-1926
82.
M. Andachi T. Nakayama M. Kawasaki S. Kurokawa H.-P. Loock 《Applied physics. B, Lasers and optics》2007,88(1):131-135
Visible and near-infrared laser light pulses were coupled into two different types of optical fiber cavities. One cavity consisted
of a short strand of fiber waveguide that contained two identical fiber Bragg gratings. Another cavity was made using a loop
of optical fiber. In either cavity ∼40 ps laser pulses, which were generated using a custom-built gain-switched diode laser,
circulated for a large number of round trips. The optical loss of either cavity was determined from the ring-down times. Cavity
ring-down spectroscopy was performed on 200 pL volumes of liquid samples that were injected into the cavities using a 100 μm
gap in the fiber loop. A detection limit of 20 ppm of methylene blue dye in aqueous solution, corresponding to a minimum absorptivity
of εC<6 cm-1, was realized.
PACS 42.62.Fi; 42.81.-i 相似文献
83.
M.-W. Chu Y. Shingaya T. Nakayama 《Applied Physics A: Materials Science & Processing》2007,86(1):101-106
A combined transmission electron microscopy (TEM) and Raman spectroscopy study has been performed on nanocrystalline Ba0.9Sr0.1TiO3 (BST) crystals and tubes. TEM investigations revealed the existence of 90 deg ferroelastic twins in the materials. Raman spectra showed an obvious shoulder (∼750 cm-1) from the broad band at ∼720 cm-1 that nominally represents the quasimode of E(LO4) and A1(LO3). The intensity of this shoulder increases with the twin population in the nanocrystalline materials, suggesting a correlation between the lattice dynamical characteristics and the long-range ferroelastic strain of the twin wall. The ferroelastic strain is mainly constrained along the c-axis of the BST unit cell, and the effect of this constraint is more pronounced in nanocrystalline materials than in bulks due to a significant wall volume ratio in twinned nano-materials. A1 phonons showing collective ion dynamics along the c-direction could be then hardened by the strain, while E symmetry exhibiting vibrations perpendicular to the c-axis would be less affected. The theoretically predicted giant LO–TO coupling in tetragonal ferroelectric perovskites [18] suggests that the hardening of the softest A1(TO1) mode in A1 symmetry is accompanied by that of the hardest A1(LO3) phonon. Consequently, the shoulder could be ascribed to the ferroelastic strain induced hardening of the quasimode with a considerable contribution from the A1(LO3) phonon. PACS 61.72.Ff; 63.22.+m; 77.80.Bh; 77.80.Dj 相似文献
84.
Koichi Fukase Hideo Nakayama Motohiro Kurosawa Toshiki Ikegaki Takeshi Kanoh Sumihiro Hase 《Journal of carbohydrate chemistry》2013,32(5):715-736
Abstract New bifunctional reagents, 2-amino-6-carboxyethylpyridine and 2-amino-6-cyanoethylpyridine, were designed and synthesized in order to provide a novel procedure for preparation of neoglycoconjugates from fluorescence-labeled and purified sugar chains. Labeling of model sugar chains with these reagents was effected by reductive amination using BH3.Me2NH to give corresponding 6-carboxyethylpyridylaminated (CEPA-) and 6-cyanoethylpyridylaminated (CNEPA-) derivatives, which were readily purified by reversed phase HPLC. The reagent parts of the labeled products possess the functional groups which then serve as linkers for coupling with matrices such as proteins and polymers. A CEPA-derivative of glucose was directly coupled with the ε-amino group of a Lys derivative to give a neoglycoprotein model. CNEPA-sugars were hydrogenated to give 6-aminopropylpyridylaminated (APPA-) derivatives, which can then be readily used for the preparation of various types of neoglycoconjugates by use of appropriate spacers as exemplified by the coupling of APPA-maltotriose with bovine serum albumin (BSA), biotin, and acrylic acid. The reaction of APPA-maltotriose with succinimidyl 3-(3-nitro-2-pyridyldithio)propionate gave the corresponding amide to be used for a disulfide formation with BSA. Condensation with biotin was effected by use of N-hydroxysuccinimidobiotin. The conjugation of APPA-maltotriose with acrylic acid was carried out by use of 4-acryloyloxyphenyldimethylsulfonium methylsulfate to give the corresponding acrylamide, which can be used for the preparation of sugar-acrylamide copolymers. 相似文献
85.
In order to understand the nonlinear effect in a two‐layer system, fully nonlinear strongly dispersive internal‐wave equations, based on a variational principle, were proposed in this study. A simple iteration method was used to solve the internal‐wave equations in order to solve the equations stably. The applicability of the proposed numerical computation scheme was confirmed to agree with linear dispersion relation theoretically obtained from variational principle. The proposed computational scheme was also shown to reproduce internal waves including higher‐order nonlinear effect from the analysis of internal solitary waves in a two‐layer system. Furthermore, for the second‐order numerical analysis, the balance of nonlinearity and dispersion was found to be similar to the balance assumed in the KdV theory and the Boussinesq‐type equations. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
86.
87.
88.
In order to confirm the existence of regions I and II in aqueous solutions of butoxyethanol(BE), the concentration and temperature
dependences of enthalpies of mixing of aqueous BE solutions with some organic solvents were measured. It has been found that
the increments of apparent enthalpies of mixing per mole of water with respect to the mole fraction of BE change irregularly
at a certain concentration. This concentration nearly corresponds to the reported boundary between regions I and II. Although
similar behavior has also been observed in aqueous solutions of iso-butoxyethanol, aqueous solutions oftert-butoxyethanol have shown no anomalous behaviors.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
89.
90.
Tsukiho Hayashi Ayumi Osawa Takehiro Watanabe Yoshiko Murata Atsushi Nakayama Kosuke Namba 《Tetrahedron letters》2017,58(20):1961-1964
1,3a,6a-Triazapentalene (TAP)-labeled enterobactin was developed as an iron ion sensor. 3-Acetylated-TAP was successfully introduced to the catechol ring of enterobactin, a well-recognized siderophore secreted by various Gram-negative bacteria. The fluorescence of TAP-labeled enterobactin decreased gradually as the amount of Fe3+ ion as an additive was increased, and 1.2 equiv of Fe3+ ion completely quenched the fluorescence. In clear contrast, when other metal ions were used, the fluorescence of TAP-labeled enterobactin remained even at 5.0 equiv. 相似文献