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1.
Takumi Taninaka Yuji Minoura 《Journal of polymer science. Part A, Polymer chemistry》1976,14(3):685-692
Polymerization of vinyl monomers having large negative e values in the presence of phosphorus compounds containing halogens was studied in order to examine the cationic initiation ability of phosphorus compounds. N-Vinylcarbazole was effectively polymerized by phosphorus compounds such as PCI3, PBr3, PCI2C6H5, PCI(C6H5)2, POCI3, and POCI2C6H5 even in benzene. The initiation ability of phosphorus compounds decreased in the order; PCI2 ? PBr3 > PCI2C6H5 > PCI(C6H5)2, and also POCI3 > POCI265. On the other hand, PCI3 and PBr3, which were less effective than POCI3, showed initiation ability for the polymerizations of styrene and α-methylstyrene in nitrobenzene as a solvent. The results of the copolymerization of styrene with methyl methacrylate by PCI3 in nitrobenzene, the result of solvent dielectric constant effect, and the effect of additives such as water, tert-butyl chloride, triethylamine, and hydroquinone, indicate the polymerization of styrene by PCI3 to proceed by a cationic mechanism. 相似文献
2.
A computer-generated hologram was recorded on a thermoplastic film using an electron-beam recording device. The hologram was a binary one of detour phase type and of surface relief type. A bright image was reconstructed from the recorded hologram. 相似文献
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4.
Tomoyuki Maruyama Takumi Muto Toshitaka Tatsumi Kazuo Tsushima Anthony W. Thomas 《Nuclear Physics A》2005,760(3-4):319-345
The possibility of kaon condensation in high-density symmetric nuclear matter is investigated including both s- and p-wave kaon–baryon interactions within the relativistic mean-field (RMF) theory. Above a certain density, we have a collective state carrying the same quantum numbers as the antikaon. The appearance of the state is caused by the time component of the axial-vector interaction between kaons and baryons. It is shown that the system becomes unstable with respect to condensation of K– pairs. We consider how the effective baryon masses affect the kaon self-energy coming from the time component of the axial-vector interaction. Also, the role of the spatial component of the axial-vector interaction on the possible existence of the collective kaonic states is discussed in connection with Λ-mixing effects in the ground state of high-density matter. Implications of condensation for high-energy heavy-ion collisions are briefly mentioned. 相似文献
5.
It is well known that a pseudo-Kähler structure is one of the natural generalizations of a Kähler structure. In this paper, we consider Ricci curvature tensor of certain compact pseudo-Kähler solvmanifolds. 相似文献
6.
A new method for rotation and brightness invariant pattern recognition was proposed by applying multiple circular harmonic expansions to the joint transform correlator. The amplitudes of the multiple orders of circular harmonic expansions made from a detecting image were synthetically modified to respond to the same auto-correlation peaks. These modified circular harmonic expansions were arranged in the input plane as reference patterns together with an arbitrary target pattern, and the correlation signals between them were calculated in the subtracted joint transform correlator. The fraction of the correlation-peak intensities between the target and the references were extracted as a new discrimination parameter. This new parameter performs pattern recognition under rotation and brightness invariance with good discriminability. Its high discriminability has been proved in computer simulations using the face image patterns of many individuals. 相似文献
7.
Optical Review - We investigate a method to evaluate light-scattering properties and chromophore concentrations in human skin tissue through diffuse reflectance spectroscopy using the reflectance... 相似文献
8.
Tsutomu Asano Shota Sano Toshihiko Okabe Takumi Sano Chie Sawatari 《Journal of Macromolecular Science: Physics》2018,57(5):317-332
Using a modified method developed from Vonk's method, detailed values of crystallinity and crystal disorder were obtained by wide angle X-ray diffraction (WAXD). In Vonk's method, the crystallinity (w) is determined by extrapolation of the WAXD experimental curve back to zero scattering angle, while the distortion factor (k) is determined by the inclination of the experimental curve at zero scattering angle. In our new method, both w and k are determined at the same time by using the least squares method. In order to show the efficiency of our method, the new fitting procedure was applied to the experimental values of polyethylene and polyethylene terephthalate as measured by Vonk, and the values of w and k determined by our new method were compared with those found by Vonk's method. The new fitting method has the advantage that it uses the whole experimental curve. Moreover, our modified Vonk's method enables us to discuss crystal distortions as arising from first-kind (thermal) disorder and second-kind (paracrystalline) disorder. 相似文献
9.
Masai H Fujiwara T Matsumoto S Takahashi Y Iwasaki K Tokuda Y Yoko T 《Optics letters》2011,36(15):2868-2870
The authors have demonstrated white light emission of rare earth (RE)-free Mn-doped SnO-ZnO-P(2)O(5) glass. The RE-free glass shows white light emission with a high value of quantum efficiency (QE) comparable to conventional crystalline phosphor. It is notable that the high QE value is attained for RE-free transparent glass, and the broad emission can be continuously tuned by both the amount of activator and the composition of the glass. Since this glass possesses low-melting property, we emphasize that the glass phosphor will lead to the development of a novel inorganic white-light-emitting device in combination with a solid state UV light-emitting source. 相似文献
10.