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71.
Hirokazu Fukidome Kei Tanaka Kazuyuki Ueda Toyohiko Kinoshita 《Surface science》2007,601(20):4675-4679
The ultrathin oxidation of a H/Si(1 0 0) surface with microfabricated pn-junctions was studied by photoemission electron microscopy (PEEM), mirror electron microscopy (MEM) and microscopic X-ray photoelectron spectroscopy (μ-XPS). The ultrathin oxidation inverts the contrast of the junctions in PEEM images. It is found by analyzing the intensity profiles of images that the potential distribution across the pn-junctions is also inverted by the oxidation. The charging of the oxide by ultraviolet irradiation from a light source of PEEM is attributed as the cause of the inversion of the contrast shown by μ-XPS and MEM. 相似文献
72.
Takashi Yoshida Rong Lu Shuqin Han Kazuyuki Hattori Takahiro Katsuta Kei‐Ichi Takeda Kazutoshi Sugimoto Masamitsu Funaoka 《Journal of polymer science. Part A, Polymer chemistry》2009,47(3):824-832
For the synthesis of a new biologically functional polymer from a natural resource by an environment‐friendly method, the laccase‐catalyzed polymerization of a lignin‐based macromonomer, lignocatechol, was carried out for the first time in ethanol–phosphate buffer solvent system to give crosslinked polymers in good yields. Lignocatechol was prepared by the phase separation system of lignin and catechol in aqueous sulfuric acid. The copolymerization was also performed with urushiol to afford the corresponding copolymers in high yields. The polymerization mechanism was estimated by the IR and pyrolysis GC‐MS measurements, suggesting that the polymerization proceeded mainly at the catechol ring through a quinone radical intermediate. The thermal properties were measured by the DSC, TG, and TMA analyses, indicating that the polymers had high thermal stabilities because of the crosslinked structures. In addition, it was found that the resulting polymers had the affinity of bovine serum albumin (BSA) and glucoamylase. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 824–832, 2009 相似文献
73.
Kei Funano 《manuscripta mathematica》2009,130(3):273-285
In this paper, we prove an exponential and Ganssian concentration inequality for 1-Lipschitz maps from mm-spaces to Hadamard manifolds. In particular, we give a complete answer to a question by M. Gromov. 相似文献
74.
Inagi S Koseki K Hayashi S Fuchigami T 《Langmuir : the ACS journal of surfaces and colloids》2010,26(24):18631-18633
The electrochemical reduction of a fluorene-based conjugated polymer, poly(9-fluorenone-alt-9,9-dioctylfluorene), was investigated for the first time. The carbonyl group in the fluorenone unit was selectively and quantitatively converted to the methylene group, as determined by (1)H NMR, IR, and energy-dispersive X-ray (EDX) analysis. The optical and electrochemical properties of the polymers were studied by UV-vis, photoluminescence (PL), and cyclic voltammetry (CV) measurements and were found to be tunable by varying the reduction level. 相似文献
75.
76.
A wide class of Higgs sectors is investigated in supersymmetric standard models. When the lightest Higgs boson (h ) looks the standard model one, the mass (mh) and the triple Higgs boson coupling (the hhh coupling) are evaluated at the one-loop level in each model. While mh is at most 120–130 GeV in the minimal supersymmetric standard model (MSSM), that in models with an additional neutral singlet or triplet fields can be much larger. The hhh coupling can also be sensitive to the models: while in the MSSM the deviation from the standard model prediction is not significant, that can be 30–60% in some models such as the MSSM with the additional singlet or with extra doublets and charged singlets. These models are motivated by specific physics problems like the μ-problem, the neutrino mass, the scalar dark matter and so on. Therefore, when h is found at the CERN Large Hadron Collider, we can classify supersymmetric models by measuring mh and the hhh coupling accurately at future collider experiments. 相似文献
77.
We consider the extended Higgs models, in which one of the isospin doublet scalar fields carries the hypercharge Y=3/2. Such a doublet field Φ3/2 is composed of a doubly charged scalar boson as well as a singly charged one. We first discuss a simple model with Φ3/2 (Model I), and study its collider phenomenology at the LHC. We then consider a new model for radiatively generating neutrino masses with a dark matter candidate (Model II), in which Φ3/2 and an extra Y=1/2 doublet as well as vector-like singlet fermions carry the odd quantum number for an unbroken discrete Z2 symmetry. We also discuss the neutrino mass model (Model III), in which the exact Z2 parity in Model II is softly broken. It is found that the doubly charged scalar bosons in these models show different phenomenological aspects from those which appear in models with a Y=2 isospin singlet field or a Y=1 triplet one. They could be clearly distinguished at the LHC. 相似文献
78.
We consider properties related to weighted composition operators boundedly acting from the classical Hardy space H p to H q for \({1 \leq q < p < \infty}\) . Especially, we shall completely determine path connected components in the set of weighted composition operators and explicitly characterize by function-theoretic properties of analytic self-maps. 相似文献
79.
Kei Kamada Takayuki Yanagida Martin Nikl Akihiro Fukabori Akira Yoshikawa Kenji Aoki 《Journal of Crystal Growth》2010,312(19):2795-2798
Pr1%:K(Y1−xLux)3F10 (x=0, 0.2, 0.4) single crystals were grown by the μ-PD method. All the grown crystals were greenish and perfectly transparent without any inclusions or cracks. Radioluminescence spectra and decay kinetics of the Pr1%:K(Y,Lu)3F10 crystals were measured. Emission from the Pr3+ 5d–4f transition, peaking around 260 nm and of the decay time of around 22 ns were observed. The 5d–4f emission intensities of the Pr1%:K(Y,Lu)3F10 crystals were higher than that of the standard BGO scintillator. 相似文献
80.
Denuders are widely used for atmospheric analysis. Annular denuders are especially well-suited for preconcentration of trace gases compared to simpler single tube designs. While traditionally coated annular denuders have both bounding surfaces that behave as sinks, annular denuders/membrane-based scrubbers with the same basic geometric design and with only one of the annular surfaces functioning as sink (e.g., a membrane tube whose outer surface behaves as a sink disposed within an inert jacket tube) have become common. However, the gas collection efficiency of such devices cannot be expressed as a simple equation with fixed constants and there is no presently available tool to a priori determine the denuder performance or to design denuders with specific removal efficiencies at specific sampling rates. This paper presents a simple to use “spreadsheet calculator” for concentric annular denuders of any dimension based on known solutions to analogous heat transfer problems. The results from the present spreadsheet calculator are compared with results from a commercial computational fluid dynamics package (Fluent™; this takes significant expertise and development effort to run)—the two approaches produce essentially the same results. The present spreadsheet calculator can be used easily and simply without training and will be a useful tool for denuder users and designers. 相似文献