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91.
Mitsuhiro Hirata Yutaka Abe Bungo Ochiai Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2010,48(20):4385-4392
Various star‐shaped poly(phenoxy propylene sulfide)s (PPSs) bearing curable end groups were synthesized by the functionalization of the propagating ends of star‐shaped poly(PPS) with various electrophilies. The functionalization with chloromethyl styrene proceeded quantitatively, and afforded polymers with Mn almost agreed with theoretical value and narrow Mw/Mn. The photocuring conditions were optimized, and the addition of 10 wt % of poly(ethylene glycol) diacrylate was effective to attain sufficient crosslinking. The photocuring reaction of the end‐functionalized poly(PPS) films cast on silicon wafers was conducted by UV irradiation. The cured poly (PPS)s became insoluble in THF, supporting the sufficient crosslinking. Developing of a cured polymer yielded a negative photoresist pattern. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
92.
93.
Makoto Kudo Tomoyoshi Mishima Satoshi Iwamoto Toshihiro Nakaoka Yasuhiko Arakawa 《Physica E: Low-dimensional Systems and Nanostructures》2004,21(2-4):275
Self-assembled GaSb quantum dots (QDs) with a photoluminescence wavelength longer than 1.3 μm were successfully grown by suppressing the replacement of As and Sb on the surface of the GaSb QDs. This result means that GaSb can thus join InAs or GaInAs as a suitable material for QD lasers for optical communications. 相似文献
94.
The decaying process of a large surface potential of as-deposited Alq3 film was analyzed with consideration of electrostatic energies stored in the film. The analysis includes the cooperative molecular field effect and it shows that the derived equilibrium condition of dipolar films with electron traps supports the concept of the alignment of Fermi-level of metal and surface Fermi-level of dipolar films. The potential decay of Alq3 films on Al electrodes by photo-exposure is explained due to detrapping of trapped electrons that are immediately transported to the injected electrodes along with the disordering of polar structure of Alq3 films. 相似文献
95.
Akira Iwamoto 《Zeitschrift für Physik A Hadrons and Nuclei》1994,349(3-4):265-268
Semiclassical treatment of the tunneling through a multi-dimensional potential barrier is given. We discuss first about methods to calculate the minimum action trajectory. Next, we discuss the adiabatic approximation to the minimum action trajectory. We apply these two methods to the calculation of spontaneous fission. Finally we discuss some problems which should be solved to calculate more realistic penetration problems. 相似文献
96.
Mitsuhiro T. Nakao Yoshitaka Watanabe 《Journal of Computational and Applied Mathematics》1994,50(1-3):401-410
This paper is an extension of the preceding study (Nakao, this journal, 1991) in which we described a numerical verification method of the solution for one-space dimensional parabolic problems, to the several-space dimensional case. Here, numerical verification means the automatic proof of the existence of solutions to the problems by some numerical techniques on a computer. We reformulate the verification condition for nonlinear parabolic initial boundary value problems using the fixed-point problem of a compact operator on certain function spaces. As in the preceding study based upon a simple C0 finite-element approximation and its constructive a priori error estimates, a numerical verification procedure is presented with some numerical examples. 相似文献
97.
Y. Kobayashi M. Katada H. Sano T. Okada K. Asai M. Iwamoto F. Ambe 《Hyperfine Interactions》1990,54(1-4):585-589
99Ru,61Ni,57Fe and119Sn Mössbauer spectroscopic studies were made on ternary intermetallic compounds containing ruthenium, RuxY3?xZ (Y=Fe, Ni; Z=Si, Sn). In the system of RuxFe3?xSi, two different hyperfine magnetic fields were observed at the99Ru nuclei (H hf[Ru]) in the range ofx≤1.0 and the magnitude of eachH hf[Ru] was found to decrease with an increase in the ruthenium concentrationx. Both the99Ru and119Sn Mössbauer spectra of Ru2FeSn could be analyzed with two sets of magnetically split lines. The61Ni Mössbauer spectra of Ru2NiSn were obtained at 5 and 77 K. 相似文献
98.
Dr. Shintaro Ishida Dr. Takashi Abe Dr. Fumiya Hirakawa Tomoyuki Kosai Katsuhiro Sato Prof. Dr. Mitsuo Kira Prof. Dr. Takeaki Iwamoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(43):15100-15103
A persistent dialkylsilanone was synthesized by the dehydrobromination of a dialkylbromosilanol with tris(trimethylsilyl)silyl potassium in solution at ?80 °C: It was characterized by NMR and IR spectroscopy, and was tested in several reactions. In 29Si NMR spectrum in [D8]toluene, the signal due to the unsaturated silicon nuclei was observed at 128.7 ppm. Reactions of the dialkylsilanone with water and mesitonitrile oxide gave a silanediol and a [2+3] cycloadduct, respectively. The silanone remains intact in [D8]toluene below ?80 °C for at least two days, while it undergoes unprecedented isomerization to give a siloxysilene by means of 1,3‐silyl migration at higher temperatures. 相似文献
99.
Michiko Shimizu Tsuguyuki Saito Yoshiharu Nishiyama Shinichiro Iwamoto Hiroyuki Yano Akira Isogai Takashi Endo 《Macromolecular rapid communications》2016,37(19):1581-1586
The dimensions of nanocelluloses are important factors in controlling their material properties. The present study reports a fast and robust method for estimating the widths of individual nanocellulose particles based on the turbidities of their water dispersions. Seven types of nanocellulose, including short and rigid cellulose nanocrystals and long and flexible cellulose nanofibers, are prepared via different processes. Their widths are calculated from the respective turbidity plots of their water dispersions, based on the theory of light scattering by thin and long particles. The turbidity‐derived widths of the seven nanocelluloses range from 2 to 10 nm, and show good correlations with the thicknesses of nanocellulose particles spread on flat mica surfaces determined using atomic force microscopy.
100.
Tagaya M Ikoma T Takemura T Hanagata N Okuda M Yoshioka T Tanaka J 《Langmuir : the ACS journal of surfaces and colloids》2011,27(12):7635-7644
The adhesion process of osteoblast-like cells on hydroxyapatite (HAp) and oxidized polystyrene (PSox) was investigated using a quartz crystal microbalance with dissipation (QCM-D), confocal laser scanning microscope (CLSM), and atomic force microscope (AFM) techniques in order to clarify the interfacial phenomena between the surfaces and cells. The interfacial viscoelastic properties (shear viscosity (η(ad)), elastic shear modulus (μ(ad)), and tan δ) of the preadsorbed protein layer and the interface layer between the surfaces and cells were estimated using a Voigt-based viscoelastic model from the measured frequency (Δf) and dissipation shift (ΔD) curves. In the ΔD-Δf plots, the cell adhesion process on HAp was classified as (1) a mass increase only, (2) increases in both mass and ΔD, and (3) slight decreases in mass and ΔD. On PSox, only ΔD increases were observed, indicating that the adhesion behavior depended on the surface properties. The interfacial μ(ad) value between the material surfaces and cells increased with the number of adherent cells, whereas η(ad) and tanδ decreased slightly, irrespective of the surface. Thus, the interfacial layer changed the elasticity to viscosity with an increase in the number. The tan δ values on HAp were higher than those on PSox and exceeded 1.0. Furthermore, the pseudopod-like structures of the cells on HAp had periodic stripe patterns stained with a type I collagen antibody, whereas those on PSox had cell-membrane-like structures unstained with type I collagen. These results indicate that the interfacial layers on PSox and HAp exhibit elasticity and viscosity, respectively, indicating that the rearrangements of the extracellular matrix and cytoskeleton changes cause different cell-surface interactions. Therefore, the different cell adhesion process, interfacial viscoelasticity, and morphology depending on the surfaces were successfully monitored in situ and evaluated by the QCM-D technique combined with other techniques. 相似文献