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91.
Lead zirconate titanate (PZT) thin films were deposited on Pt/Ti/SiO2/Si and interlayer/Pt/Ti/SiO2/Si substrate by radio frequency (r.f.) magnetron sputtering with a Pb1.1Zr0.53Ti0.47O3 target. The crystallization of the PZT thin films was formed only by substrate temperature. When interlayer (PbO/TiO2) was inserted between the PZT thin film and the Pt electrode, the grain growth and processing temperature of the PZT thin films were considerably improved. Compared to PZT/Pt structure, the dielectric constant and polarization properties of the PZT/interlayer/Pt structure were fairly improved. In particular, PZT/interlayer/Pt at the substrate temperature of 400 °C showed prevalent ferroelectric properties (r=475.97, tanδ=0.0591, Pr=23 μC/cm2). As a result of an X-ray photoelectron spectroscopy (XPS) depth-profile analysis, it was found that PZT/interlayer/Pt deposited only by substrate temperature without the post-annealing process via r.f. magnetron sputtering method remained independent of each other regardless of substrate temperatures. 相似文献
92.
Park KH Jang K Kim S Kim HJ Son SU 《Journal of the American Chemical Society》2006,128(46):14780-14781
Cubic-phase InSe nanowires were synthesized. Obtaining an appropriate high reaction temperature for formation of nanocrystals using poor solubility of Se powder in oleylamine induced the generation of unusual cubic phase of InSe to form nanowires. In comparison, hexagonal-phase nanoplates were formed by dissolving Se powder in oleylamine before increase of reaction temperature. The diameter of highly monodisperse wires was controlled by varying the amount of Se. 相似文献
93.
Kim GN Kim EJ Son D Bacala A Imlay R Kirk P McNeil RR Metcalf W Cheng CP Mao ZP Yan Y Xu YT Zhu YC Abashian A Gotow K Kajino F Low E Naito F Piilonen L Childers R Darden C Lusin S Rosenfeld C Wilson S Frautschi M Kagan H Kass R Trahern CG Ko W Lander RL Maeshima K Malchow RL Higashi JR Kurihara Y Maki A Nozaki T Omori T Perez P Sagawa H Sakai Y Sugimoto Y Takaiwa Y Terada S Tsuchiya K Poling R Green J Park IH Sakamoto S Sannes F Schnetzer S Stone R Trentalange S Zimmerman D Miyano K Miyata H 《Physical review letters》1988,61(8):911-914
94.
Seon‐Kyoung Son Yoon‐Suk Choi Woo‐Hyung Lee Yongtaek Hong Jae‐Ryoung Kim Won‐Suk Shin Sang‐Jin Moon Do‐Hoon Hwang In‐Nam Kang 《Journal of polymer science. Part A, Polymer chemistry》2010,48(3):635-646
A series of new phenothiazylene vinylene‐based semiconducting polymers, poly[3,7‐(4′‐dodecyloxyphenyl)phenothiazylene vinylene] ( P1 ), poly[3,7‐(4′‐dodecyloxyphenyl)phenothiazylene vinylene‐alt‐1,4‐phenylene vinylene] ( P2 ), and poly[3,7‐(4′‐dodecyloxyphenyl)phenothiazylene vinylene‐alt‐2,5‐thienylene vinylene] ( P3 ), have been synthesized via a Horner‐Emmons reaction. FTIR and 1H NMR spectroscopies confirmed that the configurations of the vinylene groups in the polymers were all‐trans (E). The weight‐averaged molecular weights (Mw) of P1 , P2 , and P3 were found to be 27,000, 22,000, and 29,000, with polydispersity indices of 1.91, 2.05, and 2.25, respectively. The thermograms for P1 , P2 , and P3 each contained only a broad glass transition, at 129, 167, and 155 °C, respectively, without the observation of melting features. UV–visible absorption spectra of the polymers showed two strong absorption bands in the ranges 315–370 nm and 450–500 nm, which arose from absorptions of the phenothiazine segments and the conjugated main chains. Solution‐processed field‐effect transistors fabricated from these polymers showed p‐type organic thin‐film transistor characteristics. The field‐effect mobilities of P1 , P2 , and P3 were measured to be 1.0 × 10?4, 3.6 × 10?5, and 1.0 × 10?3 cm2 V?1 s?1, respectively, and the on/off ratios were in the order of 102 for P1 and P2 , and 103 for P3 . Atomic force microscopy and X‐ray diffraction analysis of thin films of the polymers show that they have amorphous structures. A photovoltaic device in which a P3 /PC71BM (1/5) blend film was used as the active layer exhibited an open‐circuit voltage (VOC) of 0.42 V, a short circuit current (JSC) of 5.17 mA cm?2, a fill factor of 0.35, and a power conversion efficiency of 0.76% under AM 1.5 G (100 mW cm?2) illumination. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 635–646, 2010 相似文献
95.
Kyung‐Sun Son Robert M. Waymouth 《Journal of polymer science. Part A, Polymer chemistry》2010,48(7):1579-1585
A series of monocyclopentadienyl titanium complexes containing a pendant amine donor on a Cp group ( A = CpTiCl3, B = CpNTiCl3, C = CpNTiCl2TEMPO, for Cp = C5H5, CpN = C5H4CH2CH2N(CH3)2, and TEMPO = 2,2,6,6‐tetramethylpiperidine‐N‐oxyl) are investigated for styrene homopolymerization and ethylene–styrene (ES) copolymerization. When activated by methylaluminoxane at 70 °C, complexes with the amine group ( B and C ) are active for styrene homopolymerization and afford syndiotactic polystyrene (sPS). The copolymerizations of ethylene and styrene with B and C yield high‐molecular weight ES copolymer, whereas complex A yields mixtures of sPS and polyethylene, revealing the critical role that the pendant amine has on the polymerization behavior of the complexes. Fractionation, NMR, and DSC analyses of the ES copolymers generated from B and C suggest that they contain sPS. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1579–1585, 2010 相似文献
96.
97.
Seung H. Son 《Journal of Number Theory》2006,121(1):114-117
Ramanujan recorded additive formulae of theta functions that are related to modular equations of degree five. We present elementary and simple proofs. 相似文献
98.
The effect of entrainment and the role of the interface during the interaction between an axisymmetric turbulent mass plume
and a strong stratified layer are investigated. We describe mainly the characteristics of the plume: the change in the profiles
of the density, the horizontal component of the velocity and the corresponding intensity of turbulence, the change in the
entrainment co-efficient, when the plume goes through the impingement interface, assuming a self-similar Gaussian property
of the axial velocity component and of the density difference. The influence of the stratification on the plume angle coefficient
is studied, and compared with the results related to a homogeneous environment, obtained elsewhere. Experimental correlation
on the mean entrainment coefficient in a given plume cross-section, is formulated. 相似文献
99.
A closed system of equations for the second moments, determining the turbulent transfer in inhomogeneous flows with body forces, is obtained in the local equilibrium approximation. Taking diffusion and convective transfer into account does not present difficulties, since the expressions obtained for the terms containing the fluctuations of the body forces and transfer terms are preserved. The effect of the external forces is considered for two cases: turbulent motion in a stratified medium and conducting flows in a longitudinal magnetic field. In the latter case the external forces are divergenceless and they therefore do not affect the pressure fluctuations. A single-scale model, in which the transverse scale is taken as the scale in the boundary layer, is considered.Translated from Izvestiya Akademii Nauk SSSS, Mekhanika Zhidkosti i Gaza, No. 3, pp. 33–40, May–June, 1985. 相似文献
100.
Phosphorescent Ruthenium Complexes with a Nitroimidazole Unit that Image Oxygen Fluctuation in Tumor Tissue 下载免费PDF全文
Dr. Aoi Son Atsushi Kawasaki Daiki Hara Dr. Takeo Ito Dr. Kazuhito Tanabe 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(6):2527-2536
Understanding oxygen fluctuation in a cancerous tumor is important for effective treatment, especially during radiotherapy. In this paper, ruthenium complexes bearing a nitroimidazole group are shown to report the oxygen status in tumor tissue directly. The nitroimidazole group was known to be accumulated in hypoxic tumor tissues. On the other hand, the ruthenium complex showed strong phosphorescence around 600 nm. The emission of ruthenium is quenched instantaneously by molecular oxygen due to energy transfer between triplet states of oxygen and ruthenium complex, but the emission is then recovered by the removal of oxygen. Thus, we could observe oxygen fluctuation in tumor tissue in a real‐time manner by monitoring the phosphorescence of the ruthenium complex. The versatility of the probe is demonstrated by monitoring oxygen fluctuation in living cells and tumor tissue planted in mice. The ruthenium complex promptly penetrated plasma membrane and accumulated in cells to emit its oxygen‐dependent phosphorescence. In vivo experiments revealed that the oxygen level in tumor tissue seems to fluctuate at the sub‐minute timescale. 相似文献