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51.
Limitations of the method using peroxidase activity of hemoglobin for detecting lipid hydroperoxides
The method using peroxidase activity of hemoglobin (Hb) for the determination of lipid peroxides was examined by using pure
methyl linoleate hydroperoxides, trilinoleoylglycerol hydroperoxides and egg yolk phosphatidylcholine hydroperoxides as substrates
and tetramethyl benzidine as electron donor for the peroxidase reaction of Hb. The reactivities of these substrates were quite
varied. Furthermore, some electron donors were tested for peroxidase activity of Hb, but none showed a complete reduction
of methyl linoleate hydroperoxides. From these results, it seems the Hb method needs to be carefully applied to biological
materials that contain mixtures of different types of lipid classes. 相似文献
52.
Ruwan Gallage Atsushi Matsuo Takeshi Fujiwara Tomoaki Watanabe Nobuhiro Matsushita Masahiro Yoshimura 《Journal of the American Ceramic Society》2008,91(7):2083-2087
Crystalline CeO2 films and patterns have been successfully fabricated in a "single-step process" at moderate temperature. In this process, the combination of the ink-jet technique and depositing the precursor on a hot substrate (≤300°C) gave crystalline CeO2 without further heat treatment. X-ray diffraction analysis revealed that the phase formed was crystallized ceria with nanosized (<10 nm) crystallites. The film thickness was several hundred nanometers and the pattern width was about 150 μm. Scanning electron microscopy analysis showed that the films and patterns were free of cracks and adhered to the substrate. This is the first report about the direct patterning of crystalline CeO2 without postfiring or posttreatments like masking, etching, etc. 相似文献
53.
A facile approach to the fabrication of ultrathin polymer films on a flat or curved substrate is presented. Polymers with unsaturated pendant groups were spin-coated on a photoinitiator tethered surface, which was then photoirradiated and washed with a solvent. The obtained films were uniform, smooth (Ra < 0.2 nm) and exhibited robustness toward solvents. The thickness of the films was determined by the molecular weight of the coated polymer and was not dependent on the initial spin-coated thickness. A mechanism for the formation of the ultrathin film and application to optical lenses is presented. 相似文献
54.
Taku Matsushita Mitsunori Hieda Nobuo Wada 《Journal of Low Temperature Physics》2011,162(5-6):536-543
To examine whether one-dimensional (1D) helium quantum fluid is realized in narrower channels than those studied previously, we have measured heat capacities of 4He adsorbed in nanoporous material FSM with straight 1D channels 1.5 nm in diameter. From the heat of desorption for adsorbed 4He, the coverage n f, up to which 4He film grows in the channels, is determined to be 15.4 ??mol/m2 using the Frenkel-Halsey-Hill model. At coverages sufficiently below n f, the temperature dependence of the 4He heat capacity has a shoulder, above which adsorbed 4He is delocalized from the substrate. On the other hand, the depression of the heat capacity indicating quantum effects has not been observed up to n f, which suggests that 4He film in the channels remains amorphous-like normal fluid. Just above n f, the quantum effect is observed in 4He adatoms on the grain surface of FSM powder, which indicates that 1.5 nm channels are slightly below the limit required to realize quantum effect in the inside 4He fluid. 相似文献
55.
Gang Zou Xian You Hideki Kohn Takaaki Manaka Mitsumasa Iwamoto 《Thin solid films》2009,518(2):750-753
An azobenzene mesogen-substituted diacetylene (NADA) monolayer has been transferred onto the solid substrate by the traditional Langmuir–Blodgett (LB) method. Solid-state polymerization of NADA LB films can be sensitized in visible light region. In situ UV–vis absorption measurement enables us to study polymerization kinetics of NADA LB films. The polymerization process can be described as a first order rate equation and polymerization rate constants are characterized in detail. Furthermore, achiral NADA molecules can form chiral LB films through overcrowded packing of the azobenzene moiety. 相似文献
56.
The photonic bands of various TiO2 photonic crystals filled with acetonitrile were investigated with the perspective for application to dye-sensitized solar cells. Finite-difference time-domain methods revealed that three-dimensional (3D) photonic crystals with diamond-log and inverse-diamond-log structures composed of TiO2 and an electrolyte had full photonic band gaps under certain conditions. The quality factor of the band gap and the electrolyte filling factor of the structures were optimized. Moreover, with the consideration for easy fabrication of such photonic crystals, two-dimensional (2D) photonic crystals, i.e., TiO2 slabs with square holes filled with electrolytes, were also investigated. Two-dimensional structures that have a full photonic band gap were also discovered. These discoveries may lead to early electrochemical applications of dye-sensitized photonic-crystal electrodes. 相似文献
57.
58.
T. Kokubo T. Matsushita H. Takadama T. Kizuki 《Journal of the European Ceramic Society》2009,29(7):1267-1274
All bioactive materials developed up to 1990 were based on calcium phosphate. It was later revealed that materials that form bonelike apatite on their surfaces in the living body bond to living bone through the apatite layer, and that apatite formation on a material is induced by various functional groups on its surface. Based on these findings, bioactive titanium was prepared by forming sodium titanates on its surface via NaOH and heat treatments, and applied to an artificial total hip joint. Porous titanium metal able to exhibit osteoconductivity as well as osteoinductivity was prepared by forming anatase on its surface via NaOH, HCl and heat treatments. Various bioactive materials with different physical properties are expected to be derived from ceramics, metals and organic polymers by modifying their surfaces with functional groups effective for apatite nucleation. 相似文献
59.
Takuhei Hashiguchi Masayuki Watanabe Akihiro Matsushita Yasunori Mitani Osamu Saeki Kiichiro Tsuji Masahide Hojo Hiroyuki Ukai 《Electrical Engineering in Japan》2008,163(3):10-18
Electric power systems in Japan are composed of remote and distributed location of generators and loads mainly concentrated in large‐demand areas. The structures having long‐distance transmission tend to produce heavy power flow with increasing electric power demand. In addition, some independent power producers (IPP) and power producer and suppliers (PPS) are participating in the power generation business, which makes power system dynamics more complex. However, there was little observation as a whole power system. In this paper the authors present a global monitoring system of power system dynamics by using the synchronized phasor measurement of demand‐side outlets. Phasor Measurement Units (PMU) are synchronized based on the global positioning system (GPS). The purpose of this paper is to show oscillation characteristics and methods for processing original data obtained from PMU after certain power system disturbances triggered by accidents. This analysis resulted in the observation of the lowest and the second lowest frequency mode. The derivation of eigenvalue with the two‐degree‐of‐freedom model brings a monitoring of two oscillation modes. Signal processing based on wavelet analysis and simulation studies to illustrate the obtained phenomena are presented in detail. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 163(3): 10– 18, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20316 相似文献
60.
K Kataoka M Taneda F Akai S Akizuki K Matsushita A Kinoshita 《Canadian Metallurgical Quarterly》1996,39(2):38-40
We experienced that therapeutic embolization of a large cerebral arteriovenous malformation (AVM) led to venous outflow obstruction resulting in intracranial hypertension in a patient who had undergone external decompression. To evaluate hemodynamic changes after embolization, we monitored the cerebrospinal fluid pressure in the next four patients who underwent endovascular treatment. The embolization of a medium AVM resulted in a slight increase in the cerebrospinal fluid pressure. In two medium AVMs, embolization produced slight decreases in the cerebrospinal fluid pressure. In a small AVM, we did not observe any changes in the cerebrospinal fluid pressure during the endovascular treatment. We discuss the mechanism of changes in the intracranial pressure after embolization and conclude that monitoring of the cerebrospinal fluid pressure immediately yields useful information for hemodynamic changes during endovascular treatment. 相似文献