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1.
Shouko Nishida Masaya Shibano Hiroshi Kamitakahara Toshiyuki Takano 《International journal of molecular sciences》2015,16(12):29093-29102
We recently observed that the decanoylation of N-phenylthiocarbamoyl chitosan (2) with a mixture of decanoic anhydride and pyridine at 60 °C for 24 h afforded N,N-(decanoyl)phenythiocarbamoyl-/2-isothiocynato chitosan decanoate (3b) rather than the expected product N,N-(decanoyl)phenylthiocarbamoyl chitosan decanoate (3a). This result suggested that some of the N,N-(decanoyl)phenylthiocarmbamoyl groups had been converted to isothiocyanate groups during the decanoylation process. The subsequent reaction of compound 3b with aniline gave N,N-(decanoyl)phenylthiocarbamoyl/N-phenylthiocarbamoyl chitosan decanoate (4) in high yield. A solution of compound 4 in CHCl3 was then added to a solution of copper decanoate (5) in the same solvent, and the resulting mixture was cast onto a glass plate to give a cast film. The film was annealed at 200 °C in an oven to give a greenish film, which showed good near-infrared absorption characteristic in the range of 800–2200 nm. 相似文献
2.
3.
A Synthetic Transcriptional Activator of Genes Associated with the Retina in Human Dermal Fibroblasts
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4.
Eicosapentaenoic acid (EPA) production by an oleaginous fungus Mortierella alpina expressing heterologous the Δ17‐desaturase gene under ordinary temperature
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5.
Shogo Mamada Naoyuki Yaguchi Masanori Hansaka Masafumi Yamato Hirohisa Yoshida 《应用聚合物科学杂志》2015,132(15)
This study was addressed to the influence of an electric field strength applied at fabrication process and matrix properties, such as the dielectric constant and the Young's modulus, on “pseudo‐1‐3 piezoelectric ceramic/polymer composite” in order to further enhance the piezoelectricity of that. The pseudo‐1‐3 piezoelectric ceramic/polymer composite consists of linearly ordered piezoelectric ceramic particles in polymer material. Silicone gel, silicone rubber, urethane rubber, and poly‐methyl‐methacrylate, which exhibit different dielectric constants and Young's modulus, were used as matrices to evaluate the matrix influence. The piezoelectricity of the pseudo‐1‐3 piezoelectric ceramic/polymer composite was evaluated using the piezoelectric strain constant d33. The d33 is one of the indices of the piezoelectric properties for piezoelectric materials. As a result, it was confirmed that d33 of the pseudo‐1‐3 piezoelectric ceramic/polymer composite increased with the increase of the electric filed strength applied at fabrication process, though, it reached a constant value at a certain strength value. Further it was confirmed that dielectric constant of the matrix had a small influence on d33 of the pseudo‐1‐3 piezoelectric ceramic/polymer composite, however, in case of matrix of lower Young's modulus, d33 was increase. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41817. 相似文献
6.
Hiroshi Takamatsu Hikaru Yamashiro Nobuo Takata Hiroshi Honda 《International Journal of Refrigeration》2003,26(6):79
Heat and mass transfer in a falling film vertical in-tube absorber was studied experimentally with LiBr aqueous solution. The presented results include the effect of solution flow rate, solution subcooling and cooling water temperature on the absorption in a smooth copper tube 16.05 mm I.D. and 400 mm long. The experimental data in the previous report for a 1200-mm-long tube was also re-examined and compared. It was demonstrated by the observation of the flow in the tube that the break down of the liquid film into rivulets leads to deterioration of heat and mass transfer at lower film Reynolds number or in longer tubes. An attempt to evaluate physically acceptable heat and mass transfer coefficients that are defined with estimated temperature and concentration at the vapor–liquid interface was also presented. 相似文献
7.
BaCuQF (Q=S, Se, Te) materials exhibit band gaps that allow transmission of much of the visible spectrum. BaCuSF is transparent in thin-film form with a band gap of 3.1 eV. Band gap estimates for powders of the solid solution series BaCuS1−xSexF were obtained from wavelength-dependent diffuse-reflectance measurements using an integrating sphere. The band gap can be tuned by the substitution of Se for S to 2.9 eV for BaCuSeF. The decrease scales almost linearly with the increase in the volume of the tetragonal unit cell, which is determined primarily by the expansion of the a lattice parameter; the overall volume increase is 7.0% from x=0 to 1. Further reduction of the band gap is observed in BaCuSe1−xTexF solid solutions, where a unit cell volume increase of 5.5% produces a band gap of 2.7 eV in BaCuSe0.5Te0.5F. Powders and films of BaCuSF exhibit strong red luminescence under ultraviolet excitation, which is suppressed by K doping. Additional tuning of band gap and electrical properties (the materials are p-type conductors) can be achieved by replacing Ba with Sr. 相似文献
8.
Masami Ikeda Susumu Fukumoto Hiroshi Takao Shinya Ohtsuka Eiichi Haginomori Masayuki Hikita 《Electrical Engineering in Japan》2002,141(4):16-24
This paper describes the dielectric breakdown characteristics of oil and oil‐impregnated paper for very fast transient (VFT) voltages. Blumlein circuits generate VFT voltages of 60 and 300 ns in a pulse width that simulates disconnecting switching surges in gas‐insulated switch gears. We measured the breakdown voltages of needle‐to‐plane, plane‐to‐plane oil gaps and several pieces of paper between plane electrodes for VFT and lightning impulse voltages. The measured data were formulated in V‐t characteristics and Weibull probability distributions. The inclination n of V‐t characteristics of insulating paper is 150, which is less than n = 13.7 of the plane‐to‐plane oil gap in the VFT time range. The shape parameters of Weibull distribution obtained in this study show that the scattering of breakdown voltages of paper is much less than that of oil. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 141(4): 16–24, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10043 相似文献
9.
Hideo Sawada Hiroshi Kakehi Masashi Koizumi Yoshihiro Katoh Masashi Miura 《Journal of Materials Science》2007,42(17):7147-7153
Fluoroalkyl end-capped N-(1,1-dimethyl-3-oxobutyl)acrylamide oligomer [RF-(DOBAA)
n
-RF] reacted with tetraethoxysilane (TEOS) and silica nanoparticles in the presence of low-molecular weight biocides such as
hibitane, hinokitiol, and hinokioil under alkaline conditions to afford RF-(DOBAA)
n
-RF/silica nanocomposites-encapsulated these biocides in excellent to moderate isolated yields. Fluoroalkyl end-capped N,N-dimethylacrylamide oligomer [RF-(DMAA)
n
-RF] and acrylic acid oligomer [RF-(ACA)
n
-RF]/silica nanocomposites-encapsulated hibitane were obtained under similar conditions. Dynamic light scattering measurements
showed that the size of these fluorinated nanocomposites-encapsulated biocides thus obtained is nanometer size-controlled.
Additionally, these fluorinated nanocomposites were shown to have a good dispersibility and stability in methanol and water.
Of particular interest, these fluorinated nanocomposites-encapsulated biocides were found to have a good antibacterial activity
against Staphylococcus aureus, and these nanocomposites were applied to the surface modification of traditional organic polymers such as poly(methyl methacrylate). 相似文献
10.
Visual evaluation experiments of color discrimination threshold and suprathreshold color‐difference comparison were carried out using CRT colors based on the psychophysical methods of interleaved staircase and constant stimuli, respectively. A large set of experimental data was generated ranged from threshold to large suprathreshold color difference at the five CIE color centers. The visual data were analyzed in detail for every observer at each visual scale to show the effect of color‐difference magnitude on the observer precision. The chromaticity ellipses from this study were compared with four previous published data, of CRT colors by Cui and Luo, and of surface colors by RIT‐DuPont, Cheung and Rigg, and Guan and Luo, to report the reproducibility of this kind of experiment using CRT colors and the variations between CRT and surface data, respectively. The present threshold data were also compared against the different suprathreshold data to show the effect of color‐difference scales. The visual results were further used to test the three advance color‐difference formulae, CMC, CIE94, and CIEDE2000, together with the basic CIELAB equation. In their original forms or with optimized KL values, the CIEDE2000 outperformed others, followed by CMC, and with the CIELAB and CIE94 the poorest for predicting the combined dataset of all color centers in the present study. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 198–208, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20106 相似文献