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排序方式: 共有713条查询结果,搜索用时 31 毫秒
81.
82.
The fluctuation propagator for the superconducting order parameter belowT c is derived for a gapless superconductor. The fluctuation of the order parameter consists of two distinct modes: the fluctuations of the phase and the modulus of the order parameter. The former fluctuation obeys a phononlike dispersion, while the latter fluctuation is described by a damping diffusion type equation. The present theory gives an account of the fluctuation-induced Josephson effect belowT c observed recently by Carlson and Goldman. 相似文献
83.
Taniguchi M Kato K Shimauchi A Ping X Nakayama H Fujita K Tanaka T Tarui Y Hirasawa E 《Journal of Bioscience and Bioengineering》2005,99(3):245-251
Cross-linked poly-gamma-glutamic acid (C-L gamma-PGA) markedly purified polluted water collected from rivers and ponds by flocculation and precipitation. This effect of C-L gamma-PGA occasionally required pretreatment with polyaluminum chloride (PAC). Components of polluted water in rivers or ponds are generally thought to be clay minerals, microorganisms and chemical compounds. In this study, the flocculating activities of C-L gamma-PGA against suspensions of bentonite, diatomaceous earth, Escherichia coli and Mycrocystis aeruginosa, and against solutions of crystal violet and bisphenol A were investigated. The mode of action of C-L gamma-PGA is thought to be based on electrostatic interaction between flocculants, C-L gamma-PGA and PAC, and the surface of polluted water components, which may lead to neutralization of the zeta-potential of those components. 相似文献
84.
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86.
The interaction of endothelin-1 (ET-1) with either interleukin-1 beta (IL-1 beta) or tumor necrosis factor alpha (TNF alpha) on the release of tissue plasminogen activator antigen (t-PA:Ag) and plasminogen activator inhibitor-1 antigen (PAI-1:Ag) was investigated in a culture system of vascular endothelial cells derived from human umbilical vein. The t-PA:Ag release was significantly decreased by either IL-1 beta or TNF alpha; ET-1 intensified the suppressive effect of the cytokines. In contrast, PAI-1:Ag release was significantly increased by either IL-1 beta or TNF alpha; ET-1 significantly reduced the stimulatory effect of the cytokines. The data suggest that endothelial cell-mediated fibrinolysis may be modulated by ET-1. 相似文献
87.
Yumiko Kaji Ryoji Mitsuhashi Xuesong Lee Hideki Okamoto Takashi Kambe Naoshi Ikeda Akihiko Fujiwara Minoru Yamaji Kenji Omote Yoshihiro Kubozono 《Organic Electronics》2009,10(3):432-436
C60 and picene thin film field-effect transistors (FETs) in bottom contact structure have been fabricated with poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) electrodes for a realization of mechanical flexible organic FETs. The C60 thin film FETs showed n-channel enhancement-type characteristics with the field-effect mobility μ value of 0.41 cm2 V?1 s?1, while the picene thin film FET showed p-channel enhancement-type characteristics with the μ of 0.61 cm2 V?1 s?1. The μ values recorded for C60 and picene thin film FETs are comparable to those for C60 and picene thin film FETs with Au electrodes. 相似文献
88.
Makoto Sakuragi Saki Tsuzuki Hirokazu Hasuda Akira Wada Kenji Matoba Izumi Kubo Yoshihiro Ito 《应用聚合物科学杂志》2009,112(1):315-319
A novel photoreactive polymer with histidine polar groups was synthesized through the copolymerization of two types of methacrylic acid, one carrying histidine groups and the other carrying azidoaniline groups. The polymer was photoimmobilized on polyester disks for surface modification. The effect of the surface modification on the hydrophilic and biofouling properties was investigated. Static contact angle measurements showed that the polymeric surface was modified to be comparatively hydrophilic in the polymer‐immobilized region. Micropattern immobilization was carried out with a photolithographic method. Atomic force microscopy measurements showed that the polymer was formed on the disks in response to ultraviolet irradiation. Protein adsorption was reduced on the polymer‐immobilized regions, and in those regions, spreading and adhesion of mammalian cells were reduced in comparison with that in nonimmobilized regions. In conclusion, a novel histidine‐containing polymer was photoreactively immobilized on a conventional polymer surface, and it had reduced interaction with proteins and cells. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
89.
Simultaneous measurements of space charge and external current were carried out using a PEA measurement system with an electrometer on the back of a grounding electrode in order to clarify the physical situation of a huge packet of positive space charges in LDPE films. A large number of positive charges from a semiconducting anode were accumulated at the interface between LDPE and an Al‐cathode at a mean applied field of 1.5 MV/cm and then finally disappeared. The results of simultaneous measurements showed that the external current kept a relatively high value during charge accumulation and further increased when the charges disappeared. Both the charge dynamics and the external current were restricted by addition of a low‐molecular‐weight paraffin wax, indicating that carrier transport was influenced by the microstructure of the polymer. The dynamics of the residual charges after short‐circuiting is also discussed. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 179(4): 10–17, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21256 相似文献
90.
Hiroshi Kishi Youichi Mizuno Tomoya Hagiwara Hirokazu Orimo Hitoshi Ohsato 《Journal of Electroceramics》2008,21(1-4):22-28
The effect of re-oxidation treatment on the solubility of dopants and the dielectric properties of rare-earths (La, Ho) and V-substituted BaTiO3 solid solutions, assuming the shell phase of X7R dielectrics, was investigated. Ho-V-substituted samples showed larger increase of the lattice parameter and T c by re-oxidation treatment compared with La-V-substituted samples. Electron spin resonance measurements revealed that the oxidation of V3+ to V4+ or V5+ appeared in the range in which the increase of lattice parameter by re-oxidation treatment was observed. This suggests that the increase of T c is due to the change of preferential occupational site of Ho ion from A-site to B-site, being accompanied with the oxidation of V3+. We also investigated the effect of re-oxidation treatment on the electrical properties and microstructure in Ni-MLCC samples, using rare-earths (La, Ho, Yb) and acceptors (Mn, V) doped BaTiO3 based X7R dielectrics. The change in temperature characteristic of the dielectric constant by re-oxidation treatment was observed for the MLCC samples containing V with smaller content. In the case of Ho-V- and Yb-V-doped samples showed larger increase of the dielectric constant at around 120 °C compared with La-V-doped samples. The relationship between the microstructure and electrical properties of the MLCC sample was investigated by impedance measurement at elevated temperature. 相似文献