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61.
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
62.
It is often the case that the naive introduction of the messenger sector to supersymmetry breaking models causes restoration of supersymmetry. We discuss a possibility of stabilizing the supersymmetry breaking vacuum by gravitational interaction. 相似文献
63.
A Numata C Takahashi R Fujiki E Kitano A Kitajima T Takemura 《Chemical & pharmaceutical bulletin》1990,38(10):2862-2865
Three antifeedants for larvae of the yellow butterfly, Eurema hecabe mandarina de l'Orza, were isolated from Osmunda japonica Thunb. and identified as osmundalin, parasorboside and methyl (3S,5S)-5-hydroxy-3-(beta-D-glucopyranosyloxy)hexanoate. In the course of isolation of the antifeedants, a new glycoside, dihydroisoosmudalin (9), was isolated together with maltol beta-D-glucopyranoside, 2-deoxy-L-ribopyranolactone, 5-hydroxymethyl.2-furfural and glycerin. The structure of 9 was elucidated as (4R,5S)-5-(beta-D-glucopyranosyloxy)hexan-4-olide on the basis of chemical and spectroscopic evidence. 相似文献
64.
65.
Frequency-locking of a CW dye laser to some absorption lines of a neon discharge by a Faraday filter
Single-mode oscillations of a CW dye laser at the center of five absorption lines from the 1s states to the 2p states of neon were obtained by means of a neon discharge Faraday filter, without any other frequency-selective elements. The most striking thing observed is that saturated absorption takes place at the center of several absorption lines in a Faraday filter, in addition to optical rotation. 相似文献
66.
Kitano H Morokoshi S Ohhori K Gemmei-Ide M Yokoyama Y Ohno K 《Journal of colloid and interface science》2004,273(1):106-114
By coupling two equivalents of N,N-diethyldithiocarbamoylmethylbenzoic acid succinimidyl ester with cystamine dihydrochloride, a disulfide-carrying compound (Cys-BDC) was prepared and used as iniferter (a compound which pursues initiation, chain transfer, and termination) in the telomerization of N,N-dimethylacrylamide and 3-acrylamidophenylboronic acid. The telomerization was carried out in the presence of N,N,N',N'-tetraethylthiuram disulfide under photoirradiation at 365 nm. An aqueous solution of the telomer obtained showed responsiveness to both temperature and sugars as confirmed by the turbidity measurements. The telomer formed a self-assembled monolayer (SAM) on a gold surface as confirmed by both cyclic voltammetry (CV) and ellipsometry. The recognition of sugar residues by the telomer SAM constructed on the gold electrode was detected by the CV measurements. The usefulness of the iniferter to prepare various telomer-carrying SAMs with bio-related functions was strongly suggested. 相似文献
67.
[reaction: see text]. Novel anodic intermolecular carbon-carbon bond formation has been accomplished by the oxidative carbon-sulfur bond fission of benzylic dithioacetals to give a wide variety of aromatic compounds. The substitution reaction successfully took place by the selective anodic oxidation of a sulfur atom of a dithioacetal. Stepwise double-substitution reactions were also achieved by the regulation of oxidation potential. 相似文献
68.
Summary The steady shear flow properties of suspensions of vinylon fibers in silicone oil were measured by means of a cone-plate type rheometer. Three kinds of vinylon fibers used had no distributions of length and were more flexible than glass fibers and the like. The content of the fibers ranged from 0 to 7 wt.%. Shear viscosity, the first normal-stress difference, yield stress, and relative viscosity were discussed. Shear viscosity and relative viscosity increased with the fiber concentration and the aspect ratio, and depended upon the shear rate. The applicability of Ziegel's equation of viscosity for fiber suspensions was investigated. The first normal-stress difference increased with the fiber concentration, aspect ratio, and shear rate and its relative increase was much larger than for shear stress and viscosity depending on the properties of the characteristic time,
The yield stress could be determined by Casson plots for large aspect ratio fiber suspensions even in low concentration comparing with the suspensions of spherical particles or powder. The influence of the flexibility of the fibers for the rheological properties of the fiber suspensions can not be ignored.With 12 figures and 2 tables 相似文献
69.
This paper presents theoretical and experimental analysis of steering performance of articulated tracked vehicles on level ground. A mathematical model for predicting the steerability of articulated units has been developed and computerized for numerical application. The accuracy of the analog has been verified by scale model tests.From the results of the simulation and scale model tests it was found that steerability was significantly improved and required sprocket torques for steering and track slippage were considerably decreased in articulated tracked vehicles when compared with a single and coupled tracked vehicles. 相似文献
70.
Summary The viscous properties of calcium carbonate filled polyethylene and polystyrene melts were examined. The relative vircosity
r defined in the previous paper gave an asymtptotic value(
r)l in the range of the shear stress below 105 dyne/cm2.(
r)l of the calcium carbonate filled system was higher than that of the glass beads or glass balloons filled system at the same volume fraction of the filler. Maron-Pierce equation with
0 = 0.44 was able to approximate the(
r)l — relationship. However, it was deduced here that the high value of(
r)l of calcium carbonyl filled system was due to the apparent increase of and this increase was attributed to the fixed polymer layer formed on the powder particle. By assuming the particle as a sphere with a diameter of 2 µm, the thickness of the fixed polymer layer was estimated as about 0.17 µm. The yield stress estimated from the Casson's plots increased exponentially with.
With 7 figures and 1 table 相似文献
Zusammenfassung Es wurden die viskosen Eigenschaften von Polyäthylen-und Polystyrol-Schmelzen untersucht, die mit Kalziumkarbonat-Teilchen gefüllt waren. Für die relative Viskosität r, wie sie in einer vorangegangenen Veröffentlichung definiert worden war, ergab sich bei Schubspannungen unterhalb 105 dyn/cm2 ein asymptotischer Wert( r)l. Dieser war bei den mit Kalziumkarbonat gefüllten Schmelzen höher als bei Schmelzen, die bis zur gleichen Volumenkonzentration mit Glaskugeln oder Glasballons gefüllt waren. Die ( r) l —-Abhängigkeit ließ sich durch eine Gleichung nachMaron und Pierce mit 0 = 0,44 beschreiben. Es wurde jedoch geschlossen, daß der hohe( r)l-Wert der mit Kalziumkarbonat gefüllten Schmelzen auf eine scheinbare Zunahme von zurückzuführen ist, verursacht durch eine feste Polymerschicht auf der Teilchenoberfläche. Unter Annahme kugelförmiger Teilchen mit einem Durchmesser von 2 µm ließ sich die zugeordnete Schichtdicke zu 0,17 µm abschätzen. Die mittels der Casson-Beziehung geschätzte Fließspannung ergab eine exponentielle-Abhängigkeit.
With 7 figures and 1 table 相似文献