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441.
442.
Motohiro Tanaka Kousuke Moritani Tomokazu Hirota Noriaki Toyoda Isao Yamada Norio Inui Kozo Mochiji 《Rapid communications in mass spectrometry : RCM》2010,24(10):1405-1410
A size‐selected argon (Ar) gas‐cluster ion beam (GCIB) was applied to the secondary ion mass spectrometry (SIMS) of a 1,4‐didodecylbenzene (DDB) thin film. The samples were also analyzed by SIMS using an atomic Ar+ ion projectile and X‐ray photoelectron spectroscopy (XPS). Compared with those in the atomic‐Ar+ SIMS spectrum, the fragment species, including siloxane contaminants present on the sample surface, were enhanced several hundred times in the Ar gas‐cluster SIMS spectrum. XPS spectra during beam irradiation indicate that the Ar GCIB sputters contaminants on the surface more effectively than the atomic Ar+ ion beam. These results indicate that a large gas‐cluster projectile can sputter a much shallower volume of organic material than small projectiles, resulting in an extremely surface‐sensitive analysis of organic thin films. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
443.
Reactions of propargylic esters with 2-substituted cyclohexane-1,3-diones and 2-oxocyclohexanecarboxylic esters in the presence of palladium catalyst are described. Substituted tetrahydrobenzofuran derivatives having a quaternary carbon stereocenter were synthesized in a highly diastereoselective manner. 相似文献
444.
Kozo Matsumoto Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2011,49(8):1874-1880
Networked polymers that had poly(ethylene glycol) (PEG) chains and lithium sulfonylimide salt structures were prepared by curing a mixture of poly(ethylene glycol) diglycidyl ether and lithium 3‐glycidyloxypropanesulfonyl‐trifluoromethanesulfonylimide with poly(ethylene glycol) bis(3‐aminopropyl) terminated. The obtained flexible self‐standing networked polymer films showed high thermal and mechanical stability with relatively high ionic conductivity. The room temperature ionic conductivity under a dry condition was in the range of 10?5 ~ 10?4 S m?1, which is one order of magnitude higher than the corresponding networked polymers having lithium sulfonate salt structures (10?6 ~ 10?5 S m?1). The film sample became swollen by immersing in propylene carbonate (PC) or PC solution of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The sample swollen in PC showed higher ionic conductivity (7.2 × 10?3 S m?1 at room temperature), and the sample swollen in 1.0 M LiTFSI/PC showed much higher ionic conductivity (8.2 × 10?1 S m?1 at room temperature). © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
445.
We observed that F centers were induced in undoped CaF2 crystals irradiated by neutrons at 18 K. 相似文献
446.
Kozo Kobayashi 《Fortschritte der Physik》1989,37(8):599-610
We notice that in the embedding of submanifolds, the fundamental equations are only the Gauss equations for the tangent vectors while the Weingarten equations for the normal equations can essentially be determined by them, and furthermore that the integrability condition of the Weingarten equations, the Ricci equations, are consitently satisfied under that of the Gauss equations. Therefore, the Weingarten and the Ricci equations do not describe essentially independent conditions for embedding. We demonstrate these facts by explicitly constructing the normal vectors from the tangent vectors. 相似文献
447.
Masaaki Yoshifuji Kozo Toyota Takahiro Sato Naoki Inamoto Ken Hirotsu 《Heteroatom Chemistry》1990,1(4):339-348
The structure of a tungstenpentacarbonyl complex of 3, 3-dipheny1-1-(2,4,6-tri-t-butylpheny1)-1-phosphaallene has been determined by X-ray analysis. 相似文献
448.
449.
Kozo Matsumoto Christain Wahnes Emiko Mouri Hideki Matsuoka Hitoshi Yamaoka 《Journal of polymer science. Part A, Polymer chemistry》2001,39(1):86-92
An amphiphilic block copolymer of silacyclobutane and methacrylic acid (MAA) was synthesized via a living anionic polymerization of 1,1‐diethylsilacylcobutane (EtSB). Sequential addition of 1,1‐diphenylethylene and t‐butyl methacrylate (tBMA) to living poly(EtSB) in the presence of lithium chloride gave poly(EtSB‐block‐tBMA) with narrow molecular weight distributions. The t‐butyl ester groups in the obtained polymer were readily hydrolyzed via heating in 1,4‐dioxane in the presence of concentrated aqueous hydrochloric acid. The block copolymer with a short MAA segment was soluble in chloroform and insoluble in methanol and basic water, whereas the block copolymer with a long MAA segment was soluble in methanol and basic water and insoluble in chloroform. The block polymer (EtSB/tBMA = 45/60) formed a monolayer film on the water surface; this was confirmed by surface pressure measurement. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 86–92, 2001 相似文献
450.
The reactions of 2,3‐dichloro‐1,4‐diphospha‐1,3‐butadiene, which is sterically protected with the 2,4,6‐tri‐t‐butylphenyl group, with some nucleophiles, including alkyllithium reagents and lithium aluminum hydrides, afforded 1,2‐diphosphinoacetylenes or 3‐phosphino‐1‐phosphaallenes. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:171–176, 2000 相似文献