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111.
112.
Hiroyasu Kondo Kazuaki Inohara Yuki Taniguchi Junko Nakahata Tetsuya Homma Hideo Takahashi 《Optical Review》2001,8(5):323-325
A thermo-optic switch in a thin-film optical waveguide was investigated. Fluorinated silicon oxide (SiOF) and organic spin-on-glass (SOG) films were used as core-layer and clad-layer, respectively, in the waveguide structure. The SiOF films were formed at 23#x00B0;C by a liquid-phase deposition (LPD) technique using a supersaturated hydrofluosilicic acid (H2SiF6) aqueous solution. Thermal coefficients of the refractive indices for LPD-SiOF and organic SOG films formed on silicon (Si) substrates were #x2212;4.0 #x00D7; 10#x2212;6/#x00B0;C, #x2212;60 #x00D7; 10#x2212;6/#x00B0;C at the wavelength of 632.8 nm, respectively. A high extinction ratio of 15 dB was obtained for this switch at the applied voltage of 12.8 V. 相似文献
113.
Kenichiro Kosugi Ratchaniwan Sutthangkul Oraphin Chaikumpollert Yoshimasa Yamamoto Jitladda Sakdapipanich Yoshinobu Isono Seiichi Kawahara 《Colloid and polymer science》2012,290(14):1457-1462
Preparation of natural rubber (NR) with a soft nanomatrix structure was made by graft-copolymerization of butyl acrylate (BA) onto deproteinized natural rubber with tert-butyl hydroperoxide/tetraetylenepentamine in latex stage. The resulting graft-copolymer of deproteinized natural rubber and poly (butyl acrylate) (DPNR-graft-PBA) was characterized by Fourier-transform infrared spectroscopy. Conversion and grafting efficiency of BA were dependent upon BA concentration, which were more than 90?mol% under a suitable condition of the graft-copolymerization. Morphology of DPNR-graft-PBA was observed by transmission electron microscopy after staining film specimens with I2 vapor for 5?min. The NR particles of about 0.5?μm in diameter were dispersed in PBA matrix of about 15?nm in thickness. Storage modulus and loss tangent of DPNR-graft-PBA were measured, and they were related with the soft nanomatrix structure. The tensile strength and elongation at break decreased as monomer concentration increased. 相似文献
114.
Makoto Kiso Keiko Ando Hiroyasu Furui Hideharu Ishida Akira Hasegawa 《Journal of carbohydrate chemistry》2013,32(7):985-990
Abstract Sialic acid-containing glycoconjugates participate in a variety of biological functions on cell surfaces, not only serving as receptors for hormones, viruses and bacteria but also as mediators in cell growth, differentiation, adhesion, oncogenesis and so on. For example, influenza virus1,2 and tripanosoma cruzi 3,4 recognize sialic acid in the time of infection to animal cells. Recently, the sialyl-Lex (sLex) and sialyl-Lea (sLea) carbohydrate epitopes have been highlighted as the ligands for selectins, a family of cell adhesion molecules involved in leukocyte traffic5,6 and tumor metastasis.7 1-Deoxynojirimycin (DNJ) and related compounds are well known8 as the potent inhibitors of a-glycosidases and glycoprotein-processing enzymes. Some of the Nsubstituted DNJ derivatives have been noted as antidiabetic and anti-HIV agents. 相似文献
115.
Arulmani Manavalan Manisha Mishra Lin Feng Siu Kwan Sze Hiroyasu Akatsu Klaus Heese 《Experimental & molecular medicine》2013,45(9):e39
This study is aimed at gaining insights into the brain site-specific proteomic senescence signature while comparing physiologically aged brains with aging-related dementia brains (for example, Alzheimer''s disease (AD)). Our study of proteomic differences within the hippocampus (Hp), parietal cortex (pCx) and cerebellum (Cb) could provide conceptual insights into the molecular mechanisms involved in aging-related neurodegeneration. Using an isobaric tag for relative and absolute quantitation (iTRAQ)-based two-dimensional liquid chromatography coupled with tandem mass spectrometry (2D-LC-MS/MS) brain site-specific proteomic strategy, we identified 950 proteins in the Hp, pCx and Cb of AD brains. Of these proteins, 31 were significantly altered. Most of the differentially regulated proteins are involved in molecular transport, nervous system development, synaptic plasticity and apoptosis. Particularly, proteins such as Gelsolin (GSN), Tenascin-R (TNR) and AHNAK could potentially act as novel biomarkers of aging-related neurodegeneration. Importantly, our Ingenuity Pathway Analysis (IPA)-based network analysis further revealed ubiquitin C (UBC) as a pivotal protein to interact with diverse AD-associated pathophysiological molecular factors and suggests the reduced ubiquitin proteasome degradation system (UPS) as one of the causative factors of AD. 相似文献
116.
117.
In?situ element-specific observation of electronic states of organic films beneath metal electrodes is achieved by x-ray absorption spectroscopy (XAS) in the bulk-sensitive fluorescence-yield (FY) mode. The molecular orientation in Au-covered oligo-thiophene films is confirmed by the C K-edge FY-XAS spectra and the applied bias dependence of the spectra is successfully detected for the first time. The present method can give deeper insights into the electronic-state investigation of various real-device systems under operational conditions. 相似文献
118.
Zheng Y Hashidzume A Takashima Y Yamaguchi H Harada A 《Langmuir : the ACS journal of surfaces and colloids》2011,27(22):13790-13795
Macroscopic molecular recognition observations were realized using polyacrylamide-based gels modified with α-cyclodextrin (α-CD), β-cyclodextrin (β-CD), 1-naphthylmethyl (1Np), and 2-naphthylmethyl (2Np) moieties, which are denoted as αCD(x)-gel, βCD(x)-gel, 1Np(y)-gel, and 2Np(y)-gel, where x and y indicate the mol % of CD and Np moieties, respectively. The αCD(5)-gel did not adhere to either the 1Np(5)-gel or 2Np(5)-gel, whereas the βCD(5)-gel interacted with both to form alternating or checkered assemblies. Although the difference in the association constants of β-CD for the model polymers was small, the βCD(x)-gel successfully discriminated between 1Np(y)-gel and 2Np(y)-gel at the appropriate x and y. 相似文献
119.
The binding of amino acids to water-soluble zinc porphyrins in basic aqueous solution was spectrophotometrically analyzed. The amino acids were bound to the porphyrins through the coordination of the N atom with the central zinc ion. Additional attractions arise due to Coulomb interactions between the -COO(-) anion of the amino acids and the -N(CH(3))(3)(+) cation of the porphyrin substituents and due to hydrophobic interactions between the porphyrin plane and the hydrophobic substituents of the amino acids. These attractions could be explained based on the binding data. The compensatory relationships of DeltaS and DeltaH were also discussed. 相似文献
120.
The direct and catalytic kinetic resolution of racemic carboxylic acids bearing a Br?nsted base such as O-protected alpha-hydroxy carboxylic acids and N-protected alpha-amino acids has been accomplished through an L-histidine-derived sulfonamide-induced enantioselective esterification reaction with tert-butyl alcohol for the first time. Highly asymmetric induction [S( k fast/ k slow) = up to 56] has been achieved under the equilibrium between a chiral catalyst and two diastereomeric acylammonium salts through an intramolecular hydrogen-bonding interaction. 相似文献