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81.
Kazuhiro Nagata Daisuke Sano Yu Shimizu Michiko Miyazaki Takuya Kanemitsu Takashi Itoh 《Tetrahedron: Asymmetry》2009,20(21):2530-2536
The catalytic asymmetric alkylation of α-cyanocarboxylates and acetoacetates with an alkyl halide was performed under phase-transfer conditions to afford compounds which have a chiral quaternary carbon with up to 97% and 94% ee, respectively. As applications of this method, chiral 2-oxindole derivatives and a β-lactam derivative were synthesized. 相似文献
82.
Yuta Kitamura Noriyuki Miyazaki Toshiro Mabuchi Teruhiko Nawata 《Journal of Crystal Growth》2009,311(15):3954-3962
We developed a method for simulating birefringence of an annealed ingot of MgF2 single crystal for lithography optics. This method provides the optical path difference caused by crystal symmetry and residual stress existing in the crystal. The method consists of the heat conduction analysis, the residual stress analysis and the birefringence analysis. Because there exists no experimental data on the inelastic behavior of MgF2 single crystal, the residual stress was estimated with the elastic thermal stress analysis using the finite element method by assuming a stress-free temperature. In this analysis, the temperature dependence of material properties and crystal anisotropy were taken into account. In the birefringence analysis, the distributions of optical path difference were calculated by an approximate method using the result of the residual stress analysis. This approximate method uses the average stress along the wave normal and is equivalent to the exact method in case of low stress dealt with the present study. In this analysis, it is possible to consider both the intrinsic birefringence and the stress birefringence in any crystal orientation. The distribution of the optical path difference in the annealed ingot obtained from the present calculation agrees qualitatively with that of the experiment. Its calculated value also agrees reasonably well with that of the experiment, when a stress-free temperature is adequately selected. 相似文献
83.
T. Kawahara M. Miyazaki A. Kimura Y. Okamoto J. Morimoto T. Miyakawa 《Applied Physics A: Materials Science & Processing》1999,69(3):343-346
The noncontact imaging of the buried structures is carried out in the open-air atmosphere by using the photothermal deflection
(PTD) method. We applied these techniques to the layered samples. Besides the PTD images for the optically opaque buried structures,
the parameters of the materials such as thermal diffusivity can also be calculated from the PTD amplitude and phase signal
in the PTD scanning images. When the PTD signals at two different modulation frequencies are used, the thermal diffusivity
of the buried structure can be obtained from the PTD signal outside of the sample nondestructively.
Received: 27 November 1998 / Accepted: 18 March 1999 / Published online: 7 July 1999 相似文献
84.
Tadashi Suzuki Takao Miyazaki Nobuyoshi Natsuaki 《Applied Physics A: Materials Science & Processing》1990,50(3):265-267
The origin of the ion beam mixing effect, which causes the formation of smooth silicide films, is investigated for the Ti/Si solid-phase silicidation reaction. Ge ion beam mixing of a conventional Ti/c-Si structure with an oxide-contaminated interface shows an obvious effect when the implant conditions are such that the Ti/Si interface is amorphized. On the other hand, silicidation without ion mixing for Ti/a-Si and Ti/c-Si structures with oxide-free interfaces, prepared by sequential deposition in UHV, results in smooth and rough film surfaces, respectively. This strongly suggests that the ion beam mixing effect primarily comes from the amorphization of the Si substrate surface rather than the destruction of the interfacial oxide film. 相似文献
85.
Akihiro Nakamoto Takeshi Saito Shota Miyazaki Masataka Nagao 《Analytica chimica acta》2010,661(1):42-46
A simple, sensitive, and specific method with gas chromatography-mass spectrometry was developed for simultaneous extraction and derivatization of amphetamines (APs) and 3,4-methylenedioxyamphetamines (MDAs) in human urine by using a monolithic silica spin column. All the procedures, such as sample loading, washing, and elution were performed by centrifugation. APs and MDAs in urine were adsorbed on the monolithic silica and derivatized with propyl chloroformate in the column. Methamphetamine-d5 was used as an internal standard. The linear ranges were 0.01-5.0 μg mL−1 for methamphetamine (MA) and 3,4-methylenedioxymethamphetamine (MDMA) and 0.02-5.0 μg mL−1 for amphetamine (AP) and 3,4-methylenedioxyamphetamine (MDA) (coefficient of correlation ≧0.995). The recovery of APs and MDAs in urine was 84-94%, and the relative standard deviation of the intra- and interday reproducibility for urine samples containing 0.1, 1.0, and 4.0 μg mL−1 of APs and MDAs ranged from 1.4% to 13.6%. The lowest detection limit (signal-to-noise ratio ≧ 3) in urine was 5 ng mL−1 for MA and MDMA and 10 ng mL−1 for AP and MDA. The proposed method can be used to perform simultaneous extraction and derivatization on spin columns that have been loaded with a small quantity of solvent by using centrifugation. 相似文献
86.
Vossen A Seidl R Adachi I Aihara H Aushev T Balagura V Bartel W Bischofberger M Bondar A Bračko M Browder TE Chang MC Chen A Chen P Cheon BG Cho K Choi Y Eidelman S Feindt M Gaur V Gabyshev N Garmash A Golob B Perdekamp MG Haba J Hayasaka K Horii Y Hoshi Y Hou WS Hyun HJ Inami K Ishikawa A Iwabuchi M Iwasaki Y Iwashita T Joshi NJ Kichimi H Kim HO Kim MJ Ko BR Kumita T Lange JS Lee MJ Lee SH Leitgab M Li Y Liu C Liventsev D Louvot R McOnie S Miyata H Miyazaki Y Mizuk R Mohanty GB Nakano E 《Physical review letters》2011,107(7):072004
The interference fragmentation function translates the fragmentation of a quark with a transverse projection of the spin into an azimuthal asymmetry of two final-state hadrons. In e(+)e(-) annihilation the product of two interference fragmentation functions is measured. We report nonzero asymmetries for pairs of charge-ordered π(+)π(-) pairs, which indicate a significant interference fragmentation function in this channel. The results are obtained from a 672 fb(-1) data sample that contains 711 × 10(6) π(+)π(-) pairs and was collected at and near the Υ(4S) resonance, with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. 相似文献
87.
Mizukami S Wu F Sakuma A Walowski J Watanabe D Kubota T Zhang X Naganuma H Oogane M Ando Y Miyazaki T 《Physical review letters》2011,106(11):117201
Spin precession with frequencies up to 280 GHz is observed in Mn(3-δ)Ga alloy films with a perpendicular magnetic anisotropy constant K(u)~15 M?erg/cm(3). The damping constant α, characterizing macroscopic spin relaxation and being a key factor in spin-transfer-torque systems, is not larger than 0.008 (0.015) for the δ=1.46 (0.88) film. Those are about one-tenth of α values for known materials with large K(u). First-principles calculations well describe both low α and large K(u) for these alloys. 相似文献
88.
Let X be a Banach space and L the generator of the evolution semigroup associated with the τ -periodic evolutionary process {U(t,s)}t≥s on the space Pτ(X) of all τ-periodic continuous X -valued functions. We give criteria for the existence of periodic solutions to nonlinear systems of the form Lp=−?F(p,?) under the condition that 1 is a normal eigenvalue of the monodromy operator U(τ,0). The proof is based on a new decomposition of the space Pτ(X) by constructing a right inverse of L. 相似文献
89.
Takuya Miyazaki 《Abhandlungen aus dem Mathematischen Seminar der Universit?t Hamburg》2014,84(1):85-122
We discuss the Fourier–Jacobi expansion of certain vector valued Eisenstein series of degree $2$ , which is also real analytic. We show that its coefficients of index $\pm 1$ can be described by using a generating series of real analytic Jacobi forms. We also describe all the coefficients of general indices in suitable manners. Our method can be applied to study another Fourier series of Saito-Kurokawa type that is associated with a cusp form of one variable and half-integral weight. Then, following the arguments in the holomorphic case, we find that the Fourier series indeed defines a real analytic Siegel modular form of degree 2. 相似文献
90.