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201.
Junpei Yamanaka Saiko Yamada Norio Ise Takuji Yamaguchi 《Journal of Polymer Science.Polymer Physics》1995,33(10):1523-1526
The isoionic dilution method, which was proposed by Pals and Hermans, for linear ionic polymer solutions, was examined for the viscosity behavior of dilute aqueous dispersion of ionic latex [particle diameter, (0.120 ± 0.003) × 10–6 m; surface charge density, 1.6 × 10–6 C/cm2] in the presence of sodium chloride (5 × 10–5 to 5 × 10–4 M). Linear relations were obtained between the reduced viscosity and the latex concentration, when a parameter m, which appeared in the effective ionic strength introduced by Pals and Hermans, was chosen to be about 0.1. This finding on the latex system does not support that, at the salt and polymer concentrations employed, the dimension of linear macroions varies with changing effective ionic strength and it is kept constant along the isoionic dilution line. Brief discussion on the m value is presented. ©1995 John Wiley & Sons, Inc. 相似文献
202.
Advanced ion-beam techniques such as metal ion-implantation, ionized cluster beam (ICB) deposition and RF-magnetron sputtering (RF-MS) deposition were found to enable the development of unique titanium oxide photocatalyst materials which are able to absorb and work not only under UV but also visible or solar light irradiation. Thus prepared visible light-responsive TiO2 act as efficient photocatalysts for the NO decomposition reaction into N2 and O2 as well as the H2 and O2 evolution reaction from water. 相似文献
203.
204.
Emiko Mouri Kozo Matsumoto Hideki Matsuoka 《Journal of Polymer Science.Polymer Physics》2003,41(16):1921-1928
A carpetlike dense‐layer formation between a hydrophobic layer and a polyelectrolyte brush layer has been found in the monolayers of an ionic amphiphilic diblock copolymer, poly(1,1‐diethylsilacyclobutane)m‐block‐poly(methacrylic acid)n, on a water surface by an X‐ray reflectivity technique. By detailed analysis, we have found that the hydrophilic layer under the water is not a simple layer but is divided into two layers, that is, a carpetlike dense methacrylic acid (MAA) layer near the hydrophobic layer and a polyelectrolyte brush layer. We have also confirmed that a well‐established polyelectrolyte brush is formed only for the m:n = 43:81 polymer monolayer: For m:n = 40:10 and m:n = 45:60 polymer monolayers, only a dense MAA layer is formed. This dense‐layer formation should be the origin of the interesting hydrophobic‐layer thickness variation previously reported; The hydrophobic‐layer thickness takes a minimum as a function of the hydrophilic chain length at any surface pressure studied. An overview of the data for three samples with different chain lengths (m:n = 40:10, 45:60, or 43:81) has shown that the thickness of this dense layer is 10–20 Å and is independent of the surface pressure and polymerization degree of poly(methacrylic acid) (PMAA) in the range studied. This dense‐layer formation is explained by the reasonable speculation that contact with PMAA is thermodynamically more stable than direct contact with water for the diethylsilacyclobutane (Et2SB) layer on water. In this sense, the dense layer acts like a carpet for the hydrophobic Et2SB layer, and a 10–20‐Å thickness could be a critical value for the carpet. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1921–1928, 2003 相似文献
205.
206.
Kitagawa Y Sentoku Y Akamatsu S Sakamoto W Kodama R Tanaka KA Azumi K Norimatsu T Matsuoka T Fujita H Yoshida H 《Physical review letters》2004,92(20):205002
An ultraintense laser injected a 10 J of power at 1.053 microm in 0.5 ps into a glass capillary of 1 cm long and 60 microm in diameter and accelerated plasma electrons to 100 MeV. One- and two-dimensional particle codes describe wakefields with 10 GV/m gradient excited behind the laser pulse, which are guided by a plasma density channel far beyond the Rayleigh range. The blueshift of the laser spectrum supports that a plasma of 10(16) cm(-3) is inside the capillary. A bump at the high energy tail suggests the electron trapping in the wakefield. 相似文献
207.
Nagayama Y Kawahata K Inagaki S Peterson BJ Sakakibara S Tanaka K Tokuzawa T Watanabe KY Ashikawa N Chikaraishi H Emoto M Funaba H Goto M Hamada Y Ichiguchi K Ida K Idei H Ido T Ikeda K Imagawa S Isayama A Isobe M Iwamoto A Kaneko O Kitagawa S Komori A Kubo S Kumazawa R Masuzaki S Matsuoka K Mito T Miyazawa J Morisaki T Morita S Motojima O Murakami S Mutoh T Muto S Nakajima N Nakamura Y Nakanishi H Narihara K Narushima Y Nishimura A Nishimura K Nishizawa A Noda N Ohdachi S Ohkubo K Ohyabu N 《Physical review letters》2003,90(20):205001
Sawtooth oscillations have been observed in current-carrying helical plasmas by using electron-cyclotron-emission diagnostics in the Large Helical Device. The plasma current, which is driven by neutral beam injection, reduces the beta threshold of the sawtooth oscillation. When the central q value is increased due to the plasma current, the core region crashes, and, when it is decreased, the edge region crashes annularly. Observed rapid mixture of the plasma in the limited region suggests that these sawtooth crashes are reconnection phenomena. Unlike previous experiments, no precursor oscillation has been observed. 相似文献
208.
A novel method for the control of peptide self-assembly has been developed by using synthetic triblock-type beta-sheet peptides composed of l- or d-amino acid, 1L and 1D, as building blocks. The peptides 1L and 1D self-assemble into beta-sheet nanofibers with left- and right-handed twists, respectively, under appropriate condition. On the other hand, the 1L/1D binary mixture was found to form only globular aggregates at the same condition. Thus, amyloid-like nanofiber formation and its nanostructure could be successfully regulated by the stereospecificity of the constituent peptide species. 相似文献
209.
Tsujibayashi T Itoh M Azuma J Watanabe M Arimoto O Nakanishi S Itoh H Kamada M 《Physical review letters》2005,94(7):076401
We have conducted two-photon spectroscopy of core excitons in BaF(2). Synchrotron radiation and laser light were used for 5p core-electron excitation and Auger-free luminescence was detected as the signal. Two-photon excitation enables access to f and p orbitals that cannot be reached by one-photon excitation of electrons in p orbitals. It has been found that the spin-orbit splittings of 4f and 6p states of the Ba ion in BaF(2) are 0.7 +/- 0.1 and 1.4 +/- 0.1 eV, respectively. 相似文献
210.
Kubo M Matsuoka K Takahashi A Shibasaki-Kitakawa N Yonemoto T 《Ultrasonics sonochemistry》2005,12(4):263-269
The degradation of phenol by ultrasonic irradiation in the presence of TiO2 was investigated in complete darkness. The effects of amount of TiO2 and the combination of TiO2 addition with gas (air or oxygen) supply on the degradation kinetics of phenol and the formation of the reaction products were examined. The degradation rate of phenol increased with the amount of TiO2. As the dissolved oxygen concentration increased by supplying oxygen, the degradation rate of phenol also increased. A kinetic model for the disappearance of phenol was proposed. The model takes into account the OH radical formation by direct water degradation, indirect degradation by oxygen atom and indirect degradation by TiO2 catalysis. The calculated results explained well the fact that a higher amount of TiO2 and dissolved oxygen concentration gave faster disappearance rate. 相似文献