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31.
A linear codimerization of 2-norbornenes with acrylic compounds such as acrylates and an acrylamide proceeded efficiently by ruthenium catalyst systems, RuCl3(tpy)/Zn (tpy = 2,2':6',2' '-terpyridine) or [RuCl2(C6H6)]2/Zn in a primary or secondary alcoholic solvent, to afford the corresponding exo-trans-2-norbornylacrylates as major products regio- and stereoselectively along with a small amount of cis isomers. The reaction of 2,5-norbornadiene with methyl acrylate also gave the linear exo-trans codimer, which was effectively catalyzed by the addition of triarylphosphines to the RuCl3(tpy)/Zn catalyst system. 相似文献
32.
The first stable 2-germadisilaallene was synthesized by the reduction of a 2 ratio 1 mixture of a stable dialkylsilylene and dichlorogermylene-dioxane complex with KC8; the 2-germadisilaallene showed dynamic disorder similar to the corresponding trisilaallene in the solid state. 相似文献
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34.
T. Idehara T. Saito H. Mori H. Tsuchiya La Agusu S. Mitsudo 《International Journal of Infrared and Millimeter Waves》2008,29(2):131-141
Long pulse operation up to 1 msec of a high frequency gyrotron with a pulse magnet has been successfully carried out in a
frequency range including 1 THz. In the experiments, the timing of an electron beam pulse injection is adjusted at the top
of the magnetic field pulse, where the variation of field intensity is negligible. The operation cavity modes seem to be TE1, 12 and TE4,12 at the second harmonics. The corresponding frequencies are 903 GHz and 1,013 GHz, respectively. Additionally several features
of radiation measurement results of the gyrotron are described and brief considerations are presented. 相似文献
35.
Palladium‐Catalyzed Domino CH/NH Functionalization: An Efficient Approach to Nitrogen‐Bridged Heteroacenes
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Natsuyo Kamimoto Dr. Dieter Schollmeyer Dr. Koichi Mitsudo Prof.Dr. Seiji Suga Prof.Dr. Siegfried R. Waldvogel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(22):8257-8261
Palladium‐catalyzed domino C?H/N?H functionalization for the synthesis of novel nitrogen‐bridged thienoacenes and 10H‐benzo[4,5]thieno[3,2‐b]indole derivatives from dihaloarene is reported. This domino sequence consists of initial C?H functionalization of the benzo[b]thiophene moiety, followed by Buchwald–Hartwig coupling. This transformation is also useful for the synthesis of highly π‐extended compounds. 相似文献
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37.
Koichi Mitsudo 《Tetrahedron letters》2008,49(51):7287-7289
Nickel pincer complex 1 was prepared by the treatment of nickel pincer 2 with AgBF4. Cationic nickel pincer complex 1 was air-stable and easy to handle, and was successfully applied to Michael addition and Mizoroki-Heck reaction. 相似文献
38.
Application of Solid Immersion Lens to Submicron Resolution Imaging of Nano-Scale Quantum Wells 总被引:1,自引:0,他引:1
We have discussed the resolution of submicron photoluminescence (PL) imaging using a solid immersion lens (SIL), which collects an evanescent light field. We apply the SIL microscope to measure PL image of a strip-line-patterned GaAs quantum well structure at low temperature. An improved resolution beyond diffraction limit and high collection efficiency of PL are realized.This paper was originally presented at the 5th International Conference on NEAR FIELD OPTICS and RELATED TECHNOLOGIES (NFO-5), which was held on December 6–10, 1998 at Coganoi Bay Hotel, Shirahama, Japan, in cooperation with the Japan Society of Applied Physics and Mombusho Grant-in Aid for Scientific Research on Priority Areas “Nearfield Nano-optics” Project, sponsored by Japan Society for the Promotion of Science. 相似文献
39.
Idehara T. Ogawa I. Mitsudo S. Pereyaslavets M. Nishida N. Yoshida K. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1999,27(2):340-354
High frequency, medium power gyrotrons (Gyrotron FU series) have been developed at Fukui University as radiation sources covering a broad band from millimeter to submillimeter wave region. They have already been applied to high frequency electron spin resonance and to submillimeter wave scattering in plasma. Many parameters of the gyrotron series could be useful for applications in several new areas. The development and some applications of the Gyrotron FU series are summarized in this paper 相似文献
40.
T. Idehara S. Mitsudo M. Pereyaslavets Y. Shimizu I. Ogawa 《International Journal of Infrared and Millimeter Waves》1999,20(7):1249-1270
At certain gyrotron operating conditions, mode cooperation instead of mode competition takes place between a fundamental and a second harmonic mode. This means the phase bunching of a gyrating electron beam under the second harmonic operation reduces the starting current for the fundamental operation and increases total output power as well as beam efficiency. Such mode cooperation is observed in experiments and confirmed by computer simulations for submillimeter wave Gyrotron FU II. 相似文献