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41.
T. Ino Y. ArimotoT. Yoshioka K. MishimaK. Taketani S. MutoH.M. Shimizu H. KiraY. Sakaguchi T. OkuK. Sakai T. ShinoharaJ. Suzuki H. OtonoH. Oide S. YamashitaS. Imajo H. FunahashiM. Yamada Y. IwashitaM. Kitaguchi M. HinoZ. Suzuki T. SanukiT. Seki K. HirotaK. Ikeda H. SatoY. Otake H. OhmoriT. Morishima T. Shima 《Physica B: Condensed Matter》2011,406(12):2424-2428
We measured the neutron beam polarization of the BL05/NOP (Neutron Optics and Physics) beamline at J-PARC with an accuracy of less than 10−3 using polarized 3He gas as a neutron spin analyzer. Precise polarimetry of the neutron beam is necessary to understand the beamline optics as well as for the asymmetry measurements of the neutron beta decay, which are planned in this beamline. 相似文献
42.
Shun-ichi Iwasaki 《Journal of magnetism and magnetic materials》2012,324(3):244-247
Development of perpendicular magnetic recording is summarized along with learning from the research study. The early stage of perpendicular recording was conducted with the research philosophy of complementarity between perpendicular and horizontal recordings. Although present production of the perpendicular recording HDDs exceeds 600 million per year, development of perpendicular recording experienced the valley of death in the 1990s. The difficult period was overcome by the collaboration system of industrial and academic communities. The research on perpendicular recording brought about development of new research model as well as the historical view of the development of technology and innovation. The huge influence of perpendicular recording on society also taught us the relationship between science and technology with culture and civilization. 相似文献
43.
Surface relief holograms are fabricated by irradiation of laser interference patterns on an azobenzene polymer film. The hologram needs no post-treatment, and can be erased by heating the films to above its glass transition temperature. Rewritable Fresnel holograms are fabricated on azo-polymer film. Replication of the surface relief hologram is also demonstrated. An application for business cards is considered. 相似文献
44.
Pd(0) complexes catalyze the 3-Aza-Cope rearrangement of N-allylenamines to the corresponding δ,ε-unsaturated imines or γ,δ-unsaturated carbonyl compounds in the presence of trifluoro-acetic acid as co-catalyst. 相似文献
45.
In this paper, twelve linear primitive reference patterns are proposed for synthesizing a matched spatial filter, known as a shape invariant filter, which can recognize all patterns with various shapes. Furthermore, reprocessed data, given by correlation between the input object of the system and the reference patterns “correlation diagrams” are introduced for processing peak signals in a digital system. By correlating the diagram from the input object with the standard diagrams, the 26 of the alphabet letters were recognized in the experiment. Moreover, feasibility of the rotational invariance of the filter was suggested by the computer simulation. 相似文献
46.
47.
Infrared spectra of binary mixtures of water with hexane and decane were measured at temperatures and pressures in the 473-648 K and 70-350 bar ranges, respectively. Volumetric concentrations of water and the hydrocarbons in the mixtures were obtained from absorption intensities of the fundamental OH stretching band of HDO and combination transitions of the hydrocarbons. Using both the concentrations, densities of the aqueous mixtures were estimated and compared with densities before mixing, which were calculated using literature densities of the neat liquids. It is found that anomalously large volume expansion on mixing occurs in the vicinity of the critical region of the mixtures. 相似文献
48.
49.
Tarniko Takahashi Shun-ichi Hirokami Masanori Nagata Takao Yamazaki 《Tetrahedron letters》1985,26(27):3247-3250
Both the irradiation of 4-pyrimidinones () and the reaction of the isolated Dewar 4-pyrimidinones () in aqueous solution gave the corresponding photohydrates () which reverted spontaneously to the starting in the dark reaction. The photohydrates were isolated in crystalline form and their physical properties were determined. 相似文献
50.
Shun-Ichi Nozakura Yotaro Morishima Shunsuke Murahashi 《Journal of polymer science. Part A, Polymer chemistry》1972,10(10):2853-2866
The branching reaction in the radical polymerization of vinyl acetate was studied kinetically. Branching occurs by polymer transfer as well as terminal double-bond copolymerization. The chain-transfer constants to the main chain (Cp,2) and to the acetoxy methyl group (Cp,1) on the polymer were calculated on the basis of the experimental data described in the preceding paper giving Cp,2 = 3.03 × 10?4, Cp,1 = 1.27 × 10?4 at 60°C, and Cp,2 = 2.48 × 10?4, Cp,1 = 0.52 × 10?4 at 0°C. Chain transfer to monomer is important with respect to the formation of the terminal double bond. The total values of transfer constants to the α- or β-position in the vinyl group and the acetoxymethyl group in vinyl acetate was determined to be 2.15 × 10?4 at 60°C. The transfer constant to the acetyl group in the monomer (Cm,1) was also evaluated to be 2.26 × 10?4 at 60°C from the quantitative determination of the carboxyl terminals in PVA. These facts suggest that the chain-transfer constant to the α- or β-position in the monomer (Cm,2) is nearly equal to zero within experimental error. Copolymerization reactivity parameters of the terminal double bond were also estimated. In conclusion, it has become clear that the formation of nonhydrolyzable branching by the terminal double-bond reaction can be almost neglected, and hence that the long branching in PVA is formed only by the polymer transfer mechanism. On the other hand, a large number of hydrolyzable branches in PVAc are prepared by the terminal double-bond reaction rather than by polymer transfer. 相似文献