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141.
We report recent progress to date on the UT‐MSL/KEK “Ultra Slow Muon” project, in which thermal muonium (Mu) atoms are generated
from the surface of a hot tungsten target placed at the primary 500 MeV proton beam line and resonantly ionized by intense
u.v. lasers synchronized with the emission of the Mu. The positive muon ionization fragments are collected by electrostatic
beam optics to form a beam of slow positive muons.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
142.
T. Nakano Y. Kishi T. Sasaki K. Sugiyama Y. Kuno T. Ikeda K. Shimomura 《Hyperfine Interactions》1997,106(1-4):291-293
We measured the residual μ+ polarizations in various liquid scintillators to search for an ideal material for an active muon stopper in which the muon
spin polarization can be preserved and at the same time their energy loss and tracks can be measured by scintillation lights
from the stopper material. We found the residual polarizations of mineral‐oil base liquid scintillators were \sim 4 times
larger than that of a plastic scintillator. Further increase of the residual polarization was observed with a mixture of CCl4.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
143.
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146.
S Miyazawa K Okano N Shimomura R S Clark T Kawahara O Asano H Yoshimura M Miyamoto Y Sakuma K Muramoto 《Chemical & pharmaceutical bulletin》1991,39(12):3215-3220
A series of triazolodiazepines was synthesized and evaluated for anti-platelet activating factor (PAF) activities. Structure-activity relationship (SAR) studies on this series revealed that the introduction of a methyl group into the 8-position of the thienodiazepine nucleus can lead to a lengthening of the duration of action. Introduction of a methyl group produced an asymmetric center and the enantiomers so formed were separated with an optical resolving column. In the in vitro assay system, the (+)-isomers displayed 50-200 times more potent anti-PAF activity than the (-)-isomers. After comparison of toxicology and pharmacokinetics, (+)-6-(2-chlorophenyl)-3- cyclopropanecarbonyl-8,11-dimethyl-2,3,4,5-tetrahydro-8H-pyrido[4' ,3':4,5]thieno[3,2-f][1,2,4]triazolo[4,3-a][1,4]diazepine (35(+)-isomer, E6123) was selected from among the compounds synthesized as a candidate for clinical study. 相似文献
147.
The grafting of polypropylene glycol (PPG) onto an ultrafine ferrite by the reaction of hydroxyl groups on the surface with isocyanate-capped PPG (PPG-NCO), prepared by the reaction of an equimolecular amount of PPG with tolylene 2,4-diisocyanate, was investigated. When PPG-NCO (M
n=2.5×103) was heated with the ferrite in bulk, the percentage of grafting onto the ferrite at 120 °C was increased up to 18.5%. On the contrary, the grafting by the reaction of PPG with hydroxyl groups on the ferrite at 120°C was scarcely observed. The grafted PPG onto the ferrite was removed by hydrolysis with a dilute methanol solution of potassium hydroxide. Therefore, it was considered that PPG was grafted onto the ferrite surface with urethane bond. The grafting of PPG onto the surface was also confirmed by infrared spectra. The reaction of PPG-NCO with the ferrite was accelerated by the addition of-picoline as a catalyst. PPG-grafted ferrite was found to produce a stable colloidal dispersion in organic solvents. Furthermore, the effect of molecular weight of PPG-NCO on the grafting onto the ferrite was discussed. 相似文献
148.
Mahara H Suematsu NJ Yamaguchi T Ohgane K Nishiura Y Shimomura M 《The Journal of chemical physics》2004,121(18):8968-8972
Even though the field of nonequilibrium thermodynamics has been popular and its importance has been suggested by Demirel and Sandler [J. Phys. Chem. B 108, 31 (2004)], there are only a few investigations of reaction-diffusion systems from the aspect of thermodynamics. A possible reason is that model equations are complicated and difficult to analyze because the corresponding chemical reactions need to be reversible for thermodynamical calculations. Here, we introduce a simple model for calculation of entropy production rate: a three-variable reversible Gray-Scott model. The rate of entropy production in self-replicating pattern formation is calculated, and the results are compared with those reported based on the Brusselator model in the context of biological cell division. 相似文献
149.
Simple fabrication of micro lens arrays 总被引:2,自引:0,他引:2
Microporous polymer films with a hexagonal arrangement of pores were prepared by simple casting of various polymer solutions under humid conditions. Hexagonally packed micropores were prepared by using condensed water droplets as templates on the surface of polymer solutions. Spherical micro lens arrays (MLAs) were fabricated simply by molding from the resulting honeycomb structures. By peeling off the upper layer with adhesive tape, the pillars were severed, forming pins on each layer, and a hexagonal array of pincushion structures was generated by this procedure. Hemispherical MLAs were also fabricated by molding the pincushion structures. The hemispherical MLAs projected clearer miniaturized images than spherical MLAs. 相似文献
150.
Kinya Shimomura Kiyoshi Ogawa Masaaki Oba Yoshihide Kotera 《Journal of solid state chemistry》1979,27(2):215-225
In the cobalt oxide-molybdenum trioxide-alumina system with a molar ratio of 1:1:1, the amounts of the high-temperature modification (a) of CoMoO4 formed during heating from 500 to 800°C and the low-temperature modification (b) formed by phase transition during the subsequent cooling to room temperature are influenced by the kinds of alumina used, such as α-, γ- and calcined γ-aluminas. Powder X-ray diffraction analysis revealed that in an α-alumina system formation of a-CoMoO4 is most favorable at a calcination temperature of 500°C and phase transition from a- to b-CoMoO4 during cooling is enhanced by higher calcination temperatures. In the γ-alumina system, formation of a-CoMoO4 is slight at 500°C but increases with increase in the calcination temperature, as does slightly the degree of phase transition from a- to b-CoMoO4 upon cooling. In a system containing calcined γ-alumina, formation of a-CoMoO4 similar to α- and γ-alumina systems was observed to occur at 500°C and 800°C, respectively, together with phase transition to b-CoMoO4 during cooling. The degree of dispersion in the CoOMoO3 coexistent system is affected by the particle size of aluminas, such as coarse α-, fine amorphous γ- and calcined γ-alumina consisting of both sizes, as observed with electron microscopy. Presence of finer γ-alumina is considered to suppress or retard the solid state reaction and phase transition. 相似文献