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81.
D. J. Rogers Y. Maeda K. Takei J. N. Chapman J. P. C. Bernards C. P. G. Schrauwen 《Journal of magnetism and magnetic materials》1994,130(1-3):433-441
We investigated the effect of a Ge underlayer and substrate temperature during film deposition (Ts) on the compositional distribution in Co79Cr21 films using spin echo nuclear magnetic resonance and preferential chemical etching. For films deposited at elevated Ts we observed drastic compositional separation (CS) leading to a Co enriched phase with approximately 5 at% Cr on both Ge and polyester. Chemical etching revealed chrysanthemum pattern (CP) type microstructures. For lower Ts films we observed less marked CS with a distinct etched microstructure in the film deposited on Ge and no clear etched microstructure in the film deposited on polyester. Results from NMR and chemical etching studies agreed very well with those from X-ray microanalysis. 相似文献
82.
Miyuki Koiso 《manuscripta mathematica》1995,87(1):311-325
We generalize the classical Steiner symmetrization to surfaces with self-intersections. Then we apply the generalized Steiner
symmetrization to several isoperimetric problems. For example, let Г⊂ℝ3 be an analytic plane Jordan curve which is symmetric with respect to a plane ϖ (ϖ⊅Г). LetS be a compact immersed surface bounded by Λ which has the smallest area among all compact surfaces bounded by Λ with a fixed
volume. In this situation, under some additional assumptions, the wholeS is proved to be symmetric with respect to ϖ. When Λ is a round circle,S is proved to be a spherical cap or the flat disk bounded by Λ without any additional assumptions.
Dedicated to Professor Hideki Ozeki on his 60th birthday
This article was processed by the author using the Springer-Verlag TEX P Jourlg macro package 1991. 相似文献
83.
Synthesis of the title compound is described. 相似文献
84.
Takashi Aoki Takahiro Kawai Tatsuya Koike Yoshitsugu Takei 《Advances in Mathematics》2004,181(1):165-189
To analyze differential operators whose WKB solutions admit infinitely many phases, we introduce a class of differential operators of WKB type and analyze their exact WKB theoretic structure near their turning points. Our analysis makes full use of techniques and ideas in microlocal analysis; we use a quantized contact transformation to construct a WKB solution of a differential equation of WKB type, and we use a Späth-type division theorem for a differential operator of WKB type to study its structure near turning points. As an application, we show a connection formula for WKB solutions near a simple turning point. 相似文献
85.
Allyl aryl ethers can be easily cleaved by the use of 10% Pd/C under mild and basic conditions. The present reaction would involve a SET process rather than a π-allyl-palladium complex. The scope and limitation of this new deprotective methodology is also described. 相似文献
86.
Miyuki Yamada 《Semigroup Forum》1984,30(1):283-290
87.
Muneo Takei 《Colloid and polymer science》1942,101(2):129-135
88.
Hirata KS Inoue K Ishida T Kajita T Kihara K Nakahata M Nakamura K Ohara S Sato N Suzuki Y Totsuka Y Yaginuma Y Mori M Oyama Y Suzuki A Takahashi K Yamada M Koshiba M Nishijima K Suda T Tajima T Miyano K Miyata H Takei H Fukuda Y Kodera E Nagashima Y Takita M Kaneyuki K Tanimori T Beier EW Feldscher LR Frank ED Frati W Kim SB Mann AK Newcomer FM Van Berg R Zhang W 《Physical review D: Particles and fields》1991,44(8):2241-2260
89.
Miyuki Hagiwara Toru Tagawa Hideo Amemiya Kunio Araki Isao Shinohara Tsutomu Kagiya 《Journal of polymer science. Part A, Polymer chemistry》1976,14(9):2167-2172
Thermal decomposition of polymer peroxide radicals formed in γ-irradiated polytetrafluoroethylene, ~CF2CF(OO·)CF2~ (radical I) and ~CF2CF2(OO~) (radical II), was studied by mass spectral analysis of the gas evolved in comparison with their photolysis with ultraviolet light. In the thermal decomposition of radicals I and II, CO2 was the most abundant component, with smaller amount of CO, CF2O, and gases present. In the photolysis, CO instead of CO2 was the most abundant in the case of radical I, while in the case of radical II, CO2 was again the main product. When a labeled polymer peroxide radical, ~CF2CF(18O-18O·)CF2~, was treated with heat or ultraviolet light, C18O16O was detected as a main component. In the treatment with ultraviolet light, a large amount of C18O comparable to that of C18O16O was also obtained. The mechanism of main-chain scission of radicals I and II is discussed. 相似文献
90.
Miyuki Hagiwara Hiroshi Mitsui Sueo Machi Tsutomu Kagiya 《Journal of polymer science. Part A, Polymer chemistry》1968,6(3):609-621
The γ-radiation-induced polymerization of ethylene with the use of liquid carbon dioxide as a solvent, was studied from the viewpoint of kinetics. The polymerization was carried out at conversions less than 10% under the pressure ranging from 100 to 400 kg./cm.2, dose rates 1.3 × 104?1.6 × 105 rad/hr., and temperatures of 20–90°C. The concentration of carbon dioxide varied up to 84.1 mole-%. The polymerization rate and the polymer molecular weight were observed to increase with reaction time. This observation, however, becomes less pronounced with increasing concentration of carbon dioxide and with rising temperature. The exponents of the pressure and the dose rate were determined to be 2.3 and 0.85 for the rate, and 2.0 and ?0.20 for the molecular weight, respectively. From the kinetic considerations for these results, the effect of carbon dioxide on the initiation and termination reaction in the polymerization was evaluated. 相似文献