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811.
Yoshida H Ikadai J Shudo M Ohshita J Kunai A 《Journal of the American Chemical Society》2003,125(22):6638-6639
Arynes, generated in situ from 2-(trimethylsilyl)aryl triflate and a fluoride ion, were found to insert into a silicon-silicon bond of cyclic disilanes in the presence of a catalytic amount of a palladium-tert-alkyl isocyanide complex to afford diverse benzo-annulated disilacarbocycles straightforwardly in modest to high yields. 相似文献
812.
Masahiko Okada Hiroshi Sumitomo Hiroto Mori H. K. Hall Ray J. H. Chan M. Bruck 《Journal of polymer science. Part A, Polymer chemistry》1990,28(12):3251-3260
A novel bicyclic oxalactam 2-oxa-5-azabicyclo [2.2.21 octan-6-one (2,5-BOL) was synthesized from sodium 3,4-dihydro-2H-pyran-2-carboxylate through a seven-step reaction sequence. Anionic ring-opening polymerization of 2,5-BOL was carried out in bulk at 12OOC or in dimethyl sulfoxide at 40, 60, and 80°C by using potassium pyrrolidonate and the N-benzoyl derivative of 2,5-BOL as catalyst and activator, respectively. The polymerization gave a new polyamide containing cis- and trans-2,5-linked tetrahydropyran rings in the main chain. The cis/trans ratio varied from 70/30 to 95 /5 depending on the reaction conditions. The polyamide having number average molecular weights of 3000–8000 was soluble in a variety of solvents including methanol, ethanol, dimethyl sulfoxide, dimethylformamide, chloroform, and dichloromethane. It began to decompose at 280–32OOC depending on the compositions of the cis- and trans-2,5-linked structural units. The anionic ring-opening polymerizability of 2,5-BOL was found to be much lower than its structural isomer, 8-oxa-6-azabicyclo[ 3.2.11 octan-7-one (8,6-BOL). 相似文献
813.
Summary For statistical inference about several normal means, the heteroscedastic method was proposed by Dudewicz and Bishop (1979,Optimizing Methods in Statistics, Academic Press, 183–203). However, the practical application in the multivariate case was not possible because it had not
been known how to construct the certain matrices required in the method. In this paper, a construction method of the matrices
is given. 相似文献
814.
T. Ozaki 《Annals of the Institute of Statistical Mathematics》1979,31(1):145-155
Summary A maximum likelihood estimation procedure of Hawkes' self-exciting point process model is proposed with explicit presentations
of the log-likelihood of the model and its gradient and Hessian. A simulation method of the process is also presented. Some
numerical results are given.
The Institute of Statistical Mathematics 相似文献
815.
K. Fujii H. Hayashii S. Iwata R. Kajikawa A. Miyamoto T. Nakanishi Y. Ohashi S. Okumi H. Ozaki T. Tauchi T. Yamaki K. Mori Y. Takeuchi 《Nuclear Physics B》1981,187(1):53-70
The polarized target asymmetry for γn→π?p was measured over the second resonance region from 0.55 to 0.9 GeV at pion c.m. angles between 60° and 120°. A double-arm spectrometer was used with a deuterated butanol target to detect both the pion and the proton, thus considerably improving the data quality. Including the new data in the amplitude analysis, the radiative decay widths of three resonances were determined more accurately than before. The results are compared with various quark models. 相似文献
816.
817.
818.
819.
The aromatic segment of rifamycin S () was synthesized from the cyclohexadienone or in high overall yield. 相似文献
820.
Ion heating and high-energy-particle production by ion-cyclotron heating in the large helical device
Mutoh T Kumazawa R Seki T Watari T Saito K Torii Y Hartmann DA Zhao Y Sasao M Isobe M Osakabe M Krasilnikov AV Ozaki T Narihara K Nagayama Y Inagaki S Shimpo F Nomura G Yokota M Akaishi K Ashikawa N de Vries P Emoto M Funaba H Fukuyama A Goto M 《Physical review letters》2000,85(21):4530-4533
Ion-cyclotron heating was applied to the Large Helical Device. When the proton-cyclotron resonance was near the saddle point of the magnetic field-strength plane, strong ion-cyclotron damping occurred. Under these conditions efficient plasma heating was achieved for more than one minute. A high-energy ion tail was observed, and the effective tail temperature was determined by a balance between the wave acceleration and the electron-drag relaxation. There was no apparent sign of particle orbit loss effect in the investigated density range of 0.8-1.3x10(19) m(-3). 相似文献