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141.
Koji Matsuo 《Annals of Global Analysis and Geometry》1995,13(1):43-54
We introduce the notion of a locally conformally Hermitian-flat manifold and derive a necessary and sufficient condition for a Hermitian manifold to be locally conformally Hermitian-flat. In addition, we construct a family of examples. 相似文献
142.
The present numerical study has dealt with the enhancement of latent heat Release by using plate type fins mounted on the vertical cooling surface in the rectangular vessel packed with molten salt as a latent heat storage material. It was found that the fin thickness and pitch exerted an influence on solidification heat transfer in a liquid layer of a nitric molten salt. The numerical results elucidated the flow pattern, velocity profile and heat transfer rate in the melted liquid layer. 相似文献
143.
A great number of experimental data indicating shock wave/boundary layer interactions in internal or external supersonic flows
were reviewed to make clear the mechanism of the interaction and to decide the onset of shock-induced separation. The interesting
conclusions were obtained for the considerably wide range of flow geometries that the onset of separation is independent of
the flow geometries and the boundary layer Reynolds number. It is found that the pressure rise necessary to separate the boundary
layer in supersonic external flows could be applied to such internal flows as overexpanded nozzles or diffusers. This is due
to the fact that the separation phenomenon caused by shock wave/boundary layer interactions is processed through a supersonic
deceleration. The shock-induced separation in almost all of interacting flow fields is governed by the concept of free interaction,
and the onset of shock-induced separation is only a function of the Mach number just upstream of shock wave. However, physical
scales of the produced separation are not independent of the downstream flow fields. 相似文献
144.
S Matsuo N Sakaguchi E Obuchi K Nakano R C Perera T Watanabe T Matsuo H Wakita 《Analytical sciences》2001,17(1):149-153
Ni L- and Ti L-edge as well as Ti K-edge X-ray absorption experiments for TiO2 thin films and Ni-doped TiO2 thin films coated on glass plates were performed using synchrotron radiation to investigate the structures around Ni and Ti ions in the films. The obtained spectra were compared with the results of theoretical calculations. It has consequently been found that the spectral features were affected by a change in the oxidizing form of Ni ions due to hydrogen reduction, by the charge variation and/or slight orbital splitting of Ti ions, and by the magnitude of the interaction between the center Ti ion and neighboring Ti ions. 相似文献
145.
A calorimetric investigation of the monolayers (MLs) of tetramethylsilane (TMS) adsorbed on graphite demonstrates two remarkable features: (i) occurrence of an orientational order–disorder phase transition in the 2-D solid (at 107 K at the coverage θ<1 and at 138 K at 1<θ<2) accompanied by a large entropy change (ranging from Rln8 to Rln3) depending on the coverage, and (ii) possible formation of a fluid bilayer around 220 K, above the 2-D critical temperature. A high-resolution incoherent neutron scattering experiment reveals a considerable motional disorder in the disordered 2-D solid. 相似文献
146.
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
147.
Tomoaki Matsugi Shin‐Ichi Kojoh Nobuo Kawahara Shingo Matsuo Hideyuki Kaneko Norio Kashiwa 《Journal of polymer science. Part A, Polymer chemistry》2003,41(24):3965-3973
Polyethylene‐block‐poly(methyl methacrylate) (PE‐b‐PMMA) was successfully synthesized through the combination of metallocene catalysis with living radical polymerization. Terminally hydroxylated polyethylene, prepared by ethylene/allyl alcohol copolymerization with a specific zirconium metallocene/methylaluminoxane/triethylaluminum catalyst system, was treated with 2‐bromoisobutyryl bromide to produce terminally esterified polyethylene (PE‐Br). With the resulting PE‐Br as an initiator for transition‐metal‐mediated living radical polymerization, methyl methacrylate polymerization was subsequently performed with CuBr or RuCl2(PPh3)3 as a catalyst. Then, PE‐b‐PMMA block copolymers of different poly(methyl methacrylate) (PMMA) contents were prepared. Transmission electron microscopy of the obtained block copolymers revealed unique morphological features that depended on the content of the PMMA segment. The block copolymer possessing 75 wt % PMMA contained 50–100‐nm spherical polyethylene lamellae uniformly dispersed in the PMMA matrix. Moreover, the PE‐b‐PMMA block copolymers effectively compatibilized homopolyethylene and homo‐PMMA at a nanometer level. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3965–3973, 2003 相似文献
148.
149.
The peroxidase activity of horse cytochrome c was enhanced by its dimerization, where its Compound III (oxy-form) and Compound I (oxoferryl porphyrin π-cation radical) species were detected in the reactions with hydrogen peroxide and meta-chloroperbenzoic acid, respectively. These results show that oligomeric cytochrome c can contribute as a proapoptotic conformer by the increased peroxidase activity. 相似文献
150.
Size selective inclusion of organic molecules into pillared carbons accompanied by large interlayer expansions was observed for the first time. In order to achieve this, the distance between two adjacent pillars should be between 0.36 and 0.40 nm and they should align in the same direction. 相似文献