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排序方式: 共有171条查询结果,搜索用时 31 毫秒
61.
62.
Chuji Aso Toyoki Kunitake Yoshikazu Ishimoto 《Journal of polymer science. Part A, Polymer chemistry》1968,6(5):1163-1174
3,4- and 3,5-Dimethylcyclopentenes were prepared as model compounds of the structural unit in polycyclopentadiene. These two isomers give characteristic NMR spectra. The assignment based on the 60 Mc./sec. spectrum was further confirmed by decoupling experiments on the 100 Mc./sec. spectrum of 3,5-dimethylcyclopentene. By comparing the NMR spectra of these compounds with that of polycyclopentadiene methods were developed for estimating the polymer structure from the relative peak area of the methine–methylene and olefinic protons. Polycyclopentadiene obtained with Friedel-Crafts catalysts at lower temperatures was shown to be composed mostly of the 1,4 and 1,2 structures. Polycyclopentadiene obtained with several Ziegler-type catalysts possessed comparable amounts of both structures, contrary to the earlier proposals. 相似文献
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64.
An ultrathin titania film with molecular-sized cavities was synthesized by treating a ca. 8 nm thick (TiO2)3(dendrimer)(TiO2)2 sandwich film with activated oxygen gas. 相似文献
65.
Toyoki KOZAI 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2013,89(10):447-461
Extensive research has recently been conducted on plant factory with artificial light, which is one type of closed plant production system (CPPS) consisting of a thermally insulated and airtight structure, a multi-tier system with lighting devices, air conditioners and fans, a CO2 supply unit, a nutrient solution supply unit, and an environment control unit. One of the research outcomes is the concept of resource use efficiency (RUE) of CPPS.This paper reviews the characteristics of the CPPS compared with those of the greenhouse, mainly from the viewpoint of RUE, which is defined as the ratio of the amount of the resource fixed or held in plants to the amount of the resource supplied to the CPPS.It is shown that the use efficiencies of water, CO2 and light energy are considerably higher in the CPPS than those in the greenhouse. On the other hand, there is much more room for improving the light and electric energy use efficiencies of CPPS. Challenging issues for CPPS and RUE are also discussed. 相似文献
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67.
Morita Kentato Motoyama Keiichi Kuramoto Ayako Onodera Risako Higashi Taishi 《Journal of inclusion phenomena and macrocyclic chemistry》2021,100(3-4):169-175
Journal of Inclusion Phenomena and Macrocyclic Chemistry - In recent years, functional materials using cyclodextrin (CD)-based polyrotaxanes have attracted considerable attention, and... 相似文献
68.
Kaji Kano Yasuhiko Tanaka Teiichiro Ogawa Masatsugu Shimomura† Toyoki Kunitake† 《Photochemistry and photobiology》1981,34(3):323-329
Abstract— Photoresponsive artificial membranes have been prepared by embedding amphiphatic alkyl-ammonium salts containing azobenzene chromophore in dipalmitoylphosphatidylcholine liposomes. The configurational change due to trans→cis photoisomerization of the azobenzene chromophore provided the perturbation of the membrane structure to result in the increase of the water and bromo-thymol blue permeability of the liposomal membranes. 相似文献
69.
Miyoshi K Aoki Y Kunitake T Fujikawa S 《Langmuir : the ACS journal of surfaces and colloids》2008,24(8):4205-4208
The fabrication of metallic nanostructures is one of the main issues in nanotechnology. This article describes the fabrication of a silver nanofin array by combining microlithography, electroless plating, and an etching technique. Fabricated Ag nanofins have a high aspect ratio (height/width = 10, width = 60 nm, height = 600 nm), and their widths and heights can be controlled by the period of electroless plating and the height of the original line pattern. An isolated Ag nanofin was proven to show metallic electrical conductivity. The current process provides a rapid and shape-designable fabrication method of metallic nanostructures. 相似文献
70.
Aoki Y Hashizume M Onoue S Kunitake T 《The journal of physical chemistry. B》2008,112(46):14578-14582
The Brunauer-Emmett-Teller (BET) surface area of 15 nm-thick films made of TiO2/polyelectrolyte bilayer was determined by quartz crystal microbalance (QCM) measurement of N2 and Ar adsorption isotherms at 77 K. The measurements were carried out using a home-built vacuum chamber that includes built-in 9 MHz QCM and cryostat units. As little as 1 ng of the adsorbed gas could be detected, and the BET surface area of a flat Au film (ca. 0.5 cm2) on an oscillator was determined within an experimental error of +/-5%. The titania/polymer composite film gives N2 and Ar adsorption isotherms consisting of a less-pronounced type-I curve and a break at around p/p0 = 0.7. This behavior is ascribed to the presence of irregular micropores and 6 nm phi-mesopores in the composite film. An analysis of the isotherms shows that the porosity of the composite film is about 12%, which is much smaller than that of bulk titania gel powder. The greater density appears to be related to the reported superior properties (robustness and resistance to electrical breakdown) of the organic/inorganic multilayer film. We conclude that the QCM-based, high-precision measurement of gas adsorption is a powerful tool for investigation of the detailed morphology of nanometer-thick films. 相似文献