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991.
992.
Syuji Fujii Motomichi Suzaki Yuichi Kakigi Kodai Aono Shin‐Ichi Yusa Yoshinobu Nakamura 《Journal of polymer science. Part A, Polymer chemistry》2011,49(7):1633-1643
Hydroxy‐functional macroazoinitiators with central azo unit have been synthesized by atom transfer radical polymerization of 2‐hydroxyethyl methacrylate or 2‐hydroxypropyl methacrylate in methanol. The mean degrees of polymerization of the polymer chains beside the azo group were fixed at 30 and 60. Proton nuclear magnetic resonance (1H NMR) and gel permeation chromatography were used to characterize the macroazoinitiators in terms of their chemical structure, molecular weight, and polydispersity, respectively. Dispersion polymerizations of styrene using the hydroxy‐functional macroazoinitiators as an inistab (initiator + colloidal stabilizer) in 2‐propanol or 2‐propanol/water media resulted in submicrometer‐sized polystyrene latex particles with hydroxy‐functional polymer hair. Electron microscopies, Fourier transform infrared spectrometer, thin layer chromatography, and 1H NMR were used to characterize the particles in terms of their morphologies, particle sizes, and their distributions and chemical compositions. The synthesized particles behaved as an effective particulate emulsifier for the stabilization of oil‐in‐water emulsions. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
993.
Jun Ichi Fujii 《Linear and Multilinear Algebra》2019,67(5):976-986
Lawson and Lim showed that the Karcher equation for positive invertible operators on a Hilbert space has a unique solution using the method of the implicit function theorem of a Banach space. In this paper, in the framework of the operator inequality, we show the equivalence of the unique solution of the Karcher equation and the self-adjointness of the Karcher mean. For this, we reform the notion of the operator power means of negative order by virtue of the Tsallis relative operator entropy of negative order. 相似文献
994.
We have analyzed phosphorus in an enzymatically digested DNA molecule using capillary electrophoresis (CE) hyphenated with inductively coupled plasma mass spectrometry (ICP-MS). The DNA concentration was quantified by the phosphorus value obtained in the CE-ICP-MS analysis. The CE-ICP-MS measurement, for which the interface device AIF-01 equipped three layered nebulizer was adopted, was achieved with limited μL/min nebulizing without loss of sample in the vaporizing chamber. The samples of nucleotides and free phosphate were separated well in the CE-ICP-MS measurement, and the calibration curve (0.1-10μg/mL) of the phosphorus showed a linear (R(2)=0.999) increase in intensity. After digestion of the 100-bp double-strand DNA sample to deoxyribonucleotide-5'-monophosphates (dNMPs) by phosphodiesterase-I, phosphorus was detected by CE-ICP-MS without further purification steps. In this study, we applied two calculation schemes of DNA analysis using a dNMP concentration obtained from CE-ICP-MS. Comparative CE-ICP-MS analysis with DNA digested to dNMPs showed that the assay gave an equal value obtained from the total DNA quantification using fluorescence detection. The detection limits of the DNA sample obtained from these species and phosphorus in nucleotides using CE-ICP-MS were 3.1-26ng/mL. These LOD values were equal to the conventional fluorescence determination of DNA. 相似文献
995.
BF3·OEt2-catalyzed methyl group migration of 4-methyl-4-tert-butyldioxycyclohexadienone, which is obtained by ruthenium-catalyzed oxidation of p-cresol with tert-butyl hydroperoxide, in hexafluoro-2-propanol/toluene gave toluquinone efficiently. The reaction can be applied to the regio-selective short-step syntheses of vitamin K3 and vitamin K1 from p-cresol. 相似文献
996.
金涛 贾宏志 侯文玫 Ryo Yamamoto Norihiro Nagai Yusaku Fujii Koichi Maru Naoya Ohta Kazuhito Shimada 《中国光学快报(英文版)》2010,(6):601-605
<正>A practical method for evaluating the three-dimensional(3D) position and velocity of a moving object used in the parabolic flight experiment is developed by using the binocular stereo vision measurement theory. The camera calibration mathematic model without considering the lens distortion is introduced.The direct linear transformation(DLT) algorithm is improved to accomplish the camera calibration.The camera calibration result and optimization algorithm are used to calculate the object's world coordinate from image coordinate.The 3D position and the velocity of the moving object are obtained.The standard uncertainty in estimating the velocity is 0.0024 m/s,which corresponds to 1%level of the velocity of the object in the experiment.The results show that this method is very useful for the parabolic flight experiments. 相似文献
997.
HAN Yun-Cheng Nobuyuki Chiga Yu Fujii Kenta Putatsukawa Osamu Hashimoto Kentaro Hirose Takatsugu Ishikawa Hiroki Kanda Masashi Kaneta Daisuke Kawama Yue Ma Kazushige Maeda Tomofumi Maruta Nayuta Maruyama Akihiko Matsumura Youhei Miyagi Koji Miwa Satoshi N. Nakamura Hajime Shimizu Koutarou Shirotori Koutaku Suzuki Tadaaki Tamae Hirokazu Tamura Kyo Tsukada WANG Tie-Shan Hirohito Yamazaki 《中国物理C(英文版)》2010,34(1)
The energy of tagged photons, which were provided from the internal photon tagging system of the Laboratory of Nuclear Science, Tohoku University, has been calibrated using the d(γ,π-pp) reaction. Charged pions and protons in the final state were detected with the Neutral Kaon Spectrometer (NKS2). Photon energies were obtained from the reaction of d(γ,π-pp). The derived photon energy was consistent with the design of the tagger system and the previous measurement using electron-positron pair production. The consistency demonstrates the performance of NKS2 and the capability of the photon energy calibration using d(γ,π-pp). 相似文献
998.
Kaori Hattori Ken'ichi Tsuchiya Kazuki Ito Yoko Okada Kotaro Fujii Hidetoshi Kubo Kentaro Miuchi Masaki Takata Toru Tanimori Hidehiro Uekusa 《Journal of synchrotron radiation》2009,16(2):231-236
The application of a two‐dimensional photon‐counting detector based on a micro‐pixel gas chamber (µ‐PIC) to high‐resolution small‐angle X‐ray scattering (SAXS), and its performance, are reported. The µ‐PIC is a micro‐pattern gaseous detector fabricated by printed circuit board technology. This article describes the performance of the µ‐PIC in SAXS experiments at SPring‐8. A dynamic range of >105 was obtained for X‐ray scattering from a polystyrene sphere solution. A maximum counting rate of up to 5 MHz was observed with good linearity and without saturation. For a diffraction pattern of collagen, weak peaks were observed in the high‐angle region in one accumulation of photons. 相似文献
999.
Takamichi Fujii Yoshikazu Hishinuma Tsuyoshi Mita Takami Arakawa 《Solid State Communications》2009,149(41-42):1799-1802
Undoped lead zirconate titanate (PZT) and Nb doped lead zirconate titanate (PNZT) films formed on an Ir/Ti/SiO2/Si substrate using an RF magnetron sputtering method were studied in detail. Films of about 3–4 μm thickness were deposited at a substrate temperature of 525 °C. X-ray diffraction measurement (XRD) shows that the obtained PZT and PNZT films are both strongly uniaxially oriented in the (100) direction of the perovskite structure, and TEM observation shows that the films have columnar structures. The addition of Nb results in changes of film electrical characteristics, particularly dielectric constant and hysteresis characteristics. Sputtered PNZT films (Nb 13 at.%) formed on silicon diaphragm structures generate 2 times more deflections than undoped PZT film formed on the same structure, thus demonstrating a superior piezoelectric performance. A sputtering method to directly form a PNZT film with high piezoelectric constant on a substrate at low temperature via electrodes finds a wide potential use in MEMS applications. 相似文献
1000.
Hirofumi Suto Keita Imai Shunjiro Fujii Shin-ichi Honda Mitsuhiro Katayama 《Surface science》2009,603(1):226-231
The solid-phase epitaxial growth process and surface structure of MnSi on Si(1 1 1) were investigated by coaxial impact-collision ion scattering spectroscopy (CAICISS) and atomic force microscopy (AFM). For the Si(1 1 1) sample deposited with 30 monolayers (ML) of Mn at room temperature, the intermixing of Mn and Si gradually started at 100 °C and reached equilibrium at approximately 400 °C. At this equilibrium state, the Mn atoms were transformed into crystalline MnSi film. Further annealing caused the desorption of Mn atoms. We identified the structure of MnSi as cubic B20 and the crystallographic orientation relationships as Si(1 1 1)//MnSi(1 1 1) and Si[]//MnSi[]. The MnSi(1 1 1) surface was found to have a dense Si terminating layer on its topmost surface. On the other hand, 3 ML of Mn deposited on Si(1 1 1) reacted with Si even at room temperature and formed a pseudomorphic structure. This structure was transformed into MnSi after annealing. A filmlike morphology with protrusions was observed for the sample with 30 ML of Mn, while island growth occurred for the sample with 3 ML of Mn. 相似文献