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61.
Watano S Okamoto T Sato Y Ohnishi Y Yasutomo T Osako Y 《Chemical & pharmaceutical bulletin》2005,53(1):18-21
A novel multi-functional vertical high shear kneader has been developed and its performance in wet kneading has previously been reported [Watano et al., Chem. Pharm. Bull., 50(3), 341-345 (2002)]. In this study, scale-up of wet kneading in the novel vertical high shear kneader was conducted. Pharmaceutical excipients composed of lactose, cornstarch and micro-crystalline cellulose were used as powder samples. Kneading operations were conducted under various operating conditions and three different vessel scales. The dried pellets were then prepared by extruding the wet kneaded masses through a dome-type extruder and their drying by a fluidized bed. The physical properties such as strength and disintegration time of the dried pellets were evaluated. It was found that the properties of the dried pellets and their scale-up characteristics were well expressed by an agitation power per unit vessel volume and dimensionless Froude number. 相似文献
62.
Hayakawa J Ikegami M Mizutani T Wahadoszamen M Momotake A Nishimura Y Arai T 《The journal of physical chemistry. A》2006,110(46):12566-12571
Photochemical properties of trans-3,3',5,5'-tetramethoxystilbene (TMST) have been studied in various polar solvents. The Stokes shift of trans-TMST was found to be increased with increasing solvent polarity. The fluorescence lifetime of trans-TMST experienced a large solvent effect changing from 2.3 ns in cyclohexane to 16.6 ns in acetonitrile. These results indicate that the excited singlet state of trans-TMST has a charge-transfer (CT) character. On the basis of the obtained results, the interior polar environment of a water-soluble TMST dendrimer is discussed. 相似文献
63.
[Structure: see text] tert-Butyl hypoiodite (t-BuOI) was found to be a powerful reagent for the cyclization of N-alkenylamides leading to a variety of N-heterocycles under extremely mild conditions. When N-alkenylsulfonamides were employed in the reaction, three- to six-membered saturated N-heterocycles were obtained in good to excellent yields with complete stereoselectivity. The method was applicable to the cyclization of alkenylbenzamide derivatives to afford N-, O- or N-, S-heterocycles. 相似文献
64.
A magnetic vortex core in a ferromagnetic circular nanodot has a resonance frequency originating from the confinement of the vortex core. By the micromagnetic simulation including the spin-transfer torque, we show that the vortex core can be resonantly excited by an ac (spin-polarized) current through the dot and that the resonance frequency can be tuned by the dot shape. The resistance measurement under the ac current successfully detects the resonance at the frequency consistent with the simulation. 相似文献
65.
Abstract It was investigated that, when an Al evaporated layer on a GaP (GaAs, GaAs1?y P y ) substrate was bombarded with total fluences of 0.1?1.0 × 1018 electrons cm?2 at 7 MeV and at 50°C, a thin heteroepitaxial layer of Al x Ga1?x P (Al x Ga1?x As, Al x Ga1?x As1?y P y ) crystal was grown on S-doped (111), (100) and (110) GaP [(110) Cr, O-doped GaAs, (100) Te-doped GaAS1?y P y ] substrates. Evidence for the creation of the epilayers before annealing was obtained from measurements using an X-ray diffractometer, an X-ray photoelectron spectrometer, a reflection high-energy electron diffractometer, a transmission electron microscope and a scanning transmission electron microscope. In the case of Al/GaP, the epitaxial layers of Al~0.25Ga~0.75P, Al~0.5Ga~0.5P and Al~0.75Ga~0.25P were grown on (111), (100) and (110) GaP substrates, respectively. Their compositions did not vary with the total electron fluence. 相似文献
66.
Facile Fabrication of Concentrated Polymer Brushes with Complex Patterning by Photocontrolled Organocatalyzed Living Radical Polymerization 下载免费PDF全文
Dr. Chen‐Gang Wang Chen Chen Dr. Keita Sakakibara Prof. Dr. Yoshinobu Tsujii Prof. Dr. Atsushi Goto 《Angewandte Chemie (International ed. in English)》2018,57(41):13504-13508
Photocontrolled surface‐initiated reversible complexation mediated polymerization (photo‐SI‐RCMP) was successfully applied to fabricate concentrated polymer brushes with complex patterning structures. Positive‐type patterned polymer brushes were obtained by photo‐SI‐RCMP under visible light (550(±50) nm) using photomasks. A particularly interesting finding was that negative‐type patterned polymer brushes were also obtainable in a facile manner. A nonspecial UV light (250–385 nm) enabled the preparation of pre‐patterned initiator surfaces in a remarkably short time (1 min), leading to negative‐type patterned polymer brushes. Based on this unique selectivity between visible and UV light, the combination of two patterning techniques enabled the preparation of complex patterned brushes, including diblock copolymers, binary polymers, and functional binary polymers, without multistep immobilization of one or more initiators on the surfaces. 相似文献
67.
Prof. Dr. Yoshinobu Isono Toshihiro Kamohara Atsushi Takano Toshio Kase 《Rheologica Acta》1997,36(3):245-251
Simultaneous measurements of stress relaxation and differential dynamic modulus were made at 268 K over a time scale of 10 to 1045 s for nearly monodisperse polybutadiene (M
w
=2.2x105, 1,2-structure 70%, M
e
=3600) and also one having coarse cross-linking (M
c
=29000). Static shear strain ranged from 0.1 to 2.0. In a long-time region (t>
k
), the relaxation modulus G (; t) could be expressed by the product G (0; t) h (y). The observed h() agreed well with the Doi-Edwards theory without use of IA approximation. Both the cured and uncured samples showed initial drop of the differential storage modulus G (), ; t) followed by gradual recovery, but did not attain the value before shearing G (, ; t) for the uncured sample showed smaller values than that for the cured one in the whole measured time scale at the higher strain, confirming the two origins of nonlinear viscoelasticity of well entangled polymer; induced chain anisotropy and induced decrement in entanglement density. G (, ; t) curves for the cured sample agreed well with the BKZ predictions. But the curves for the uncured sample agreed well with the BKZ prediction only at the time scale of t<
k
. BKZ prediction showed significant upward deviations at t>
k
. Such the differences are discussed in terms of the two origins.Dedicated to Prof. John D. Ferry on the occasion of his 85th birthday. 相似文献
68.
Toshiaki Yamaguchi Sota Shimizu Toshio Suzuki Yoshinobu Fujishiro Masanobu Awano 《Electrochemistry communications》2008,10(9):7656-1383
A high performance small-scale solid oxide fuel cell supported by a microtubular cathode was successfully developed via the extrusion of a (La0.8Sr0.2)0.97MnO3 cathode support and subsequent surface coating with a (La0.8Sr0.2)0.97MnO3–Ce0.9Gd0.1O1.95 activation layer followed by Sc2O3-doped ZrO2 electrolyte and NiO–Ce0.9Gd0.1O1.95 anode slurries. The cell was electrochemically evaluated in a humidified hydrogen (3% H2O) atmosphere, and exhibited a stable open circuit voltage above 1.05 V in the temperature range from 550 to 750 °C. Maximum power densities of 46.5, 163.2 and 452.8 mW cm−2 were generated at 550, 650 and 750 °C, respectively. The results indicate the realization of a stable and high performance cathode-supported micro SOFC. 相似文献
69.
70.
Dr. Yoshinobu Kamakura Dr. Chomponoot Suppaso Issei Yamamoto Ryusuke Mizuochi Yusuke Asai Prof. Dr. Teruki Motohashi Prof. Dr. Daisuke Tanaka Prof. Dr. Kazuhiko Maeda 《Angewandte Chemie (International ed. in English)》2023,62(28):e202305923
Certain metal complexes are known as high-performance CO2 reduction photocatalysts driven by visible light. However, most of them rely on rare, precious metals as principal components, and integrating the functions of light absorption and catalysis into a single molecular unit based on abundant metals remains a challenge. Metal-organic frameworks (MOFs), which can be regarded as intermediate compounds between molecules and inorganic solids, are potential platforms for the construction of a simple photocatalytic system composed only of Earth-abundant nontoxic elements. In this work, we report that a tin-based MOF enables the conversion of CO2 into formic acid with a record high apparent quantum yield (9.8 % at 400 nm) and >99 % selectivity without the need for any additional photosensitizer or catalyst. This work highlights a new MOF with strong potential for photocatalytic CO2 reduction driven by solar energy. 相似文献