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11.
To study a radical scavenging reaction of α-tocopherol, it was reacted with methyl radical in dimethyl sulfoxide. Two main
products, a geminal dimethyl cyclohexadienone and methyl ether of α-tocopherol, were obtained and these structures were determined
by13C nuclear magnetic resonance spectroscopy. The radical methylation data of α-tocopherol suggested that a delocalized radical
species would be an intermediate.
TMIG-RI No. 3. 相似文献
12.
Shigeki Habaue Momoko AsaiMasatake Morita Yoshio OkamotoHiroshi Uyama Shiro Kobayashi 《Polymer》2003,44(18):5195-5200
α-Methylenemacrolides having various groups, such as aromatic, ether, and amine, were enzymatically, anionically, and radically polymerized. The polymerization with the lipase catalyst successfully afforded polymers only through the ring-opening process, whereas the vinyl polymerizations selectively proceeded by using anionic and radical initiators. The polyesters obtained by the enzymatic polymerization have a polymerizable methacrylic methylene group in the main-chain, in addition to the aromatic and polar groups, and were further radically polymerized to quantitatively produce a cross-linked polymer gel. 相似文献
13.
A TiN precursor solution was synthesized by galvanostatic electrolysis of Ti metal and isopropylamine at a current density of 50 mA·cm−2 at room temperature. TiN films were prepared by dip-coating of the precursor solution on a Si wafer, followed by two-stage heat treatment at 400°C and a fixed temperature of 800–1200°C in flowing N2 , N2 /NH3 , or NH3 gas. The TiN films were characterized by XRD, chemical analysis, XPS, and electrical resistivity measurements. The TiN films were composed of uniform grains 20 to 200 nm in size with thicknesses ranging from 300 to 400 nm at temperatures of 800–1200°C. The effect of the heat treatment atmosphere (N2 and NH3 ) on the impurity content, crystallinity, particle size, and electrical resistivity is discussed. 相似文献
14.
Shiro Torizuka Kaoru Sato Hiroaki Nishio Teruo Kishi 《Journal of the American Ceramic Society》1995,78(6):1606-1610
Compacts of TiB2 with densities approaching 100% are difficult to obtain using pressureless sintering. The addition of SiC was very effective in improving the sinterability of TiB2 . The oxygen content of the raw TiB2 powder used in this research was 1.5 wt%. X-ray photoelectron spectroscopy showed that the powder surface consisted mainly of TiO2 and B2 O3 . Using vacuum sintering at 1700°C under 13–0.013 Pa, TiB2 samples containing 2.5 wt% SiC achieved 96% of their theoretical density, and a density of 99% was achieved by HIPing. TEM observations revealed that SiC reacts to form an amorphous phase. TEM-EELS analysis indicated that the amorphous phase includes Si, O, and Ti, and X-ray diffraction showed the reaction to be TiO2 + SiC → SiO2 + TiC. Therefore, the improved sinterability of TiB2 resulted from the SiO2 liquid phase that was formed during sintering when the raw TiB2 powder had 1.5 wt% oxygen. 相似文献
15.
Summary This paper describes the so-called No Catalyst Copolymerization between dioxo-1,1-thiazetidine-1,2(Ethanesultam; ESm) and 2-methyl-2-oxazoline. The copolymerization took place without any added initiator to produce copolymers of MeOZO and ESm. The structure of the copolymer was determined by the IR and NMR spectra, elemental analysis, as well as by the result of an alkaline hydrolysis of the copolymer. The reaction scheme of the copolymerization via zwitterion mechanism (Eq 3–5) was proposed. 相似文献
16.
Ken-ichi Kohichi Hiroyuki Shiro Satoshi Hitoshi Atsushi 《Sensors and actuators. B, Chemical》2008,130(2):707-712
Pt-loaded metal oxides [WO3/ZrO2, MOx/TiO2 (MOx = WO3, MoO3, V2O5), WO3 and TiO2] equipped with interdigital Au electrodes have been tested as a NOx (NO and NO2) gas sensor at 500 °C. The impedance value at 4 Hz was used as a sensing signal. Among the samples tested, Pt-WO3/TiO2 showed the highest sensor response magnitude to NO. The sensor was found to respond consistently and rapidly to change in concentration of NO and NO2 in the oxygen rich and moist gas mixture at 500 °C. The 90% response and 90% recovery times were as short as less than 5–10 s. The impedance at 4 Hz of the present device was found to vary almost linearly with the logarithm of NOx (NO or NO2) concentration from 10 to 570 ppm. Pt-WO3/TiO2 showed responses to NO and NO2 of the same algebraic sign and nearly the same magnitude, while Pt/WO3 and WO3/TiO2 showed higher response to NO than NO2. The impedance at 4 Hz in the presence of NO for Pt-WO3/TiO2 was almost equal at any O2 concentration examined (1–99%), while in the case of Pt/WO3 and WO3/TiO2 the impedance increased with the oxygen concentration. The features of Pt-WO3/TiO2 are favorable as a NOx sensor that can monitor and control the NOx concentration in automotive exhaust. The effect of WO3 loading of Pt-WO3/ZrO2-based sensor is studied to discuss the role of surface W-OH sites on the NOx sensing. 相似文献
17.
Shiro Kumano Kazuhiro Otsuka Junji Yamato Eisaku Maeda Yoichi Sato 《International Journal of Computer Vision》2009,83(2):178-194
In this paper, we propose a method for pose-invariant facial expression recognition from monocular video sequences. The advantage
of our method is that, unlike existing methods, our method uses a simple model, called the variable-intensity template, for
describing different facial expressions. This makes it possible to prepare a model for each person with very little time and
effort. Variable-intensity templates describe how the intensities of multiple points, defined in the vicinity of facial parts,
vary with different facial expressions. By using this model in the framework of a particle filter, our method is capable of
estimating facial poses and expressions simultaneously. Experiments demonstrate the effectiveness of our method. A recognition
rate of over 90% is achieved for all facial orientations, horizontal, vertical, and in-plane, in the range of ±40 degrees,
±20 degrees, and ±40 degrees from the frontal view, respectively.
Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users. 相似文献
18.
Shiro Yano Yusuke Ikemoto Hitoshi Aonuma Hajime Asama 《Robotics and Autonomous Systems》2012,60(5):722-728
It is thought that the adjustment of intraspecific aggression is an essential factor in the development of a social structure. To understand the natural laws for organizing the social structure, we focus on the fighting behavior of crickets, Gryllus bimaculatus, and investigate the neuronal mechanisms to adjust aggressiveness associated with a neuromodulatory biological amine: serotonin (5-HT).In this paper, we present a working theory of a neurophysiological mechanism based on the past biological studies on the 5-HT hypothesis, and a mathematical model of the mechanism. We analyzed this model and concluded that this neurophysiological mechanism makes the forgetting process slower. Next, we fitted our theoretical forgetting curve to an experimental curve and estimated the parameters of our model. These estimated values were in agreement with common belief in biological science. 相似文献
19.
Xiaojun Wang Takashi Takeda Naoto Hirosaki Shiro Funahashi Rong-Jun Xie 《中国稀土学报(英文版)》2018,36(1):42-48
Discovery of novel phosphors is extremely important to target the ever change of the solid state lighting technology. In this paper, we present a high-speed way to discover new phosphors, namely single-particle-diagnosis approach. This approach is based on investigating the crystal structure and luminescence of a tiny single crystal, without the necessity of the growth of large-size single crystals or the preparation of single phase powder samples. The concept of the approach and some new nitride phosphors explored by this approach are shown in this paper. 相似文献
20.
Single‐Crystal‐Like Organic Thin‐Film Transistors Fabricated from Dinaphtho[2,3‐b:2′,3′‐f]thieno[3,2‐b]thiophene (DNTT) Precursor–Polystyrene Blends
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