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排序方式: 共有97条查询结果,搜索用时 15 毫秒
1.
Wally L. Chang Kurt C. Frisch Kaneyoshi Ashida 《Journal of polymer science. Part A, Polymer chemistry》1989,27(11):3637-3649
The anionic polymerization of ?-caprolactam (CLM) has been shown to proceed at high reaction rate when catalyzed by metallic lactamates and initiated by acyllactams. The role of initiator and catalyst concentration on the process of ?-caprolactam anionic polymerization has been explored, with the aim of selecting the most suitable experimental conditions for reaction injection molding (RIM). The overall polymerization rates and physical properties for reaction injection molding of star-shaped nylon 6 homopolymer have been studied by the quasi-adiabatic process. In order to model the actual rapid molding conditions, time vs. temperature reaction profiles were measured, and the relative rates of polymerization subsequently determined from these data. 相似文献
2.
The reaction of cyclobutanone with an alkyne in the presence of a nickel(0) catalyst formally achieves intermolecular alkyne insertion between the carbonyl carbon and the α-carbon of a cyclobutanone, providing a six-membered carbocyclic skeleton. 相似文献
3.
Wally L. Chang Kurt C. Frisch Kaneyoshi Ashida 《Journal of polymer science. Part A, Polymer chemistry》1989,27(11):3619-3635
Two component interpenetrating networks (IPNs) of the SIN type (simultaneous interpenetrating networks), composed of a polyisocyanurate network and a star-shaped nylon 6, were made. The overall polymerization rates and physical properties for reaction injection molding (RIM) have been studied by the quasi-adiabatic process. In order to model the actual rapid molding conditions, time versus temperature reaction profiles were measured, and the relative rates of polymerization subsequently determined from these data. 相似文献
4.
5.
Dr. Yoichi Hoshimoto Keita Ashida Yukari Sasaoka Dr. Ravindra Kumar Prof. Dr. Ken Kamikawa Prof. Dr. Xavier Verdaguer Prof. Dr. Antoni Riera Prof. Dr. Masato Ohashi Prof. Dr. Sensuke Ogoshi 《Angewandte Chemie (International ed. in English)》2017,56(28):8206-8210
The nickel(0)-catalyzed carbonylative cycloaddition of 1,5- and 1,6-ene-imines with carbon monoxide (CO) is reported. Key to this reaction is the efficient regeneration of the catalytically active nickel(0) species from nickel carbonyl complexes such as [Ni(CO)3L]. A variety of tri- and tetracyclic γ-lactams were thus prepared in excellent yields with 100 % atom efficiency. Preliminary results on asymmetric derivatives promise potential in the synthesis of enantioenriched polycyclic γ-lactams. 相似文献
6.
Visible‐Light‐Mediated Addition of α‐Aminoalkyl Radicals to [60]Fullerene by Using Photoredox Catalysts
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Dr. Yoshihiro Miyake Yuya Ashida Dr. Kazunari Nakajima Prof. Dr. Yoshiaki Nishibayashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(20):6120-6125
The functionalization of fullerene has been extensively studied and various fullerene derivatives have been synthesized. We have succeeded in the functionalization of [60]fullerene by using α‐aminoalkyl radicals generated by visible‐light‐mediated single‐electron oxidation of α‐silylamines as synthetic intermediates. In these reactions, the introduction of diarylamino groups, which are useful electron donors, has been easily achieved. 相似文献
7.
Journal of Computer-Aided Molecular Design - In this study, a new method is proposed for calculating the relative binding free energy between a ligand and a protein, derived from a free energy... 相似文献
8.
Kameda T Zhao C Ashida J Asakura T 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2003,160(2):91-96
It is important to know the structure of silk I (Bombyx mori silk structure before spinning in the solid state) in order to understand the mechanism of fiber formation at the atomic level. In this study, 15N-dephased, 13C-observe REDOR has been carried out to determine the atomic distance of intra-molecular hydrogen bond between the 13C=O carbon of the 14th Gly residue and the 15N nitrogen of the 17th Ala residue of (AG)(6)A[1-13C]GAG[15N]AG(AG)(6) with silk I form after removal of the effect of MAS frequency on the re-coupling. The distance was determined to be 4.3A, which confirmed the intra-molecular hydrogen bonding formation between these two atomic sites. 相似文献
9.
Kise T Ogasawara T Ashida M Tomioka Y Tokura Y Kuwata-Gonokami M 《Physical review letters》2000,84(9):1986-1989
We propose a measurement setup for detecting quantum noise over a wide frequency range using inelastic transitions in a tunable two-level system as a detector. The frequency-resolving detector consists of a double quantum dot which is capacitively coupled to the leads of a nearby mesoscopic conductor. The inelastic current through the double quantum dot is calculated in response to equilibrium and nonequilibrium current fluctuations in the nearby conductor, including zero-point fluctuations at very low temperatures. As a specific example, the fluctuations across a quantum point contact are discussed. 相似文献
10.
Taichi Nakano Takashi Miyamoto Takanori Endoh Makoto Shimotani Naoki Ashida Toshishige Morioka Yutaka Takahashi 《应用有机金属化学》2004,18(2):65-67
The palladium‐catalyzed silastannation of acetylenes with tributyl(trimethylsilyl)stannane in the presence of triethylphosphite is reported for the first time. The reaction occurs at room temperature to give (Z)‐silyl(stannyl)ethenes in high yields. The protodemetallation of the resulting adducts with HCl–tetraethylammonium chloride is described first, which demonstrates that the reaction is governed only by the stability of a carbonium ion arising from the protonation to (Z)‐silyl(stannyl)ethenes rather than the hard and soft acid and base principle, i.e. the β‐cation stabilization effect (σ–π stabilization one) of a stannyl group in the carbonium ion is rather significant. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献