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71.
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
72.
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
73.
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
74.
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
75.
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
76.
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
77.
78.
A facile preparation of 3-acyl-substituted isoxazolines, benzisoxazoles, and isoxazoles from the corresponding 3-carboxylate esters is described. The process, involving reaction of the ester derivative of 3-carboxylic acid substituted heterocycles with Grignard or alkynyl lithium reagents, leads to direct generation of the corresponding 3-acyl heterocycle. The presence of α-imino ester moieties in the heterocyclic substrates for the reactions is thought to be a key feature governing the nature of these transformations. The synthetic utility of the new methodology is demonstrated by its application in a two-step route for the preparation of novel linked bis-heterocycles. 相似文献
79.
80.
Hironori Ohashi Hiroyuki Ezoe Yoshihiro Okaue Yasuhiro Kobayashi Shuji Matsuo Tsutomu Kurisaki Akane Miyazaki Hisanobu Wakita Takushi Yokoyama 《Analytical sciences》2005,21(7):789-793
The effect of UV (ultraviolet) irradiation on the adsorption of Au(III) ions on manganese dioxide and their reduction to Au(0) (gold with 0 valence state) was investigated using XPS (X-ray photoelectron spectroscopy) and 197Au M?ssbauer spectroscopy. The UV irradiation accelerated the adsorption and the reduction. From the fact that the proportion of Au(0) estimated from Au 4f XPS spectra for surface analysis was significantly smaller than that from 197Au M?ssbauer spectra for bulk analysis, we deduced that Au(0) was interpenetrated to the inside of manganese dioxide (into deeper places than about 30 A) where XPS is impossible to detect. The content of surface hydroxyl groups on manganese dioxide also increased due to the UV irradiation. The relationship between the charge in the content of hydroxyl groups and the interpenetration of Au(0) is discussed. 相似文献