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Akira Sugimoto Yasuyuki Yoshino Ryo Watanabe Kazuhiko Mizuno Kaku Uehara 《Journal of heterocyclic chemistry》1999,36(4):1057-1064
By the reaction of 5,10-dialkyl-substituted 5,10-dihydrophenazine with hydrobromic acid in dimethyl sulfoxide at 90–110°, 10-alkyl-2(10H)-phenazinone was obtained as a major product. Brominated dihydrophenazine was isolated in the case of 1,6-dichloro-5,10-dimethyl-5,10-dihydrophenazine. 相似文献
107.
This paper mainly focuses on refrigerant mixtures with relatively simple critical behavior, and presents a practical and useful method for the critical point calculation for the mixtures using mixture models based on Helmholtz energy equations of state. The expression for critical point criterion suitable for this objective is derived first. Numerical manipulations to obtain a physically correct solution are described in detail. For four binary refrigerant mixtures of difluoromethane (R-32) + pentafluoroethane (R-125), R-125 + 1,1,1,2-tetrafluoroethane (R-134a), R-125 + 1,1,1-trifluoroethane (R-143a), and R-32 + propane (R-290), the critical temperatures and critical molar volumes are calculated applying the presented method. The calculation results are compared with experimental values, and the capabilities of the mixture models for the mixtures in the critical region are discussed. 相似文献
108.
An enantioselective total synthesis of sacrolide A, an antimicrobial and cytotoxic fourteen-membered macrolactonic oxylipin isolated from an edible freshwater cyanobacterium, has been accomplished from a known carboxylic acid in 20% overall yield by a concise ten-step sequence. The key transformations include chiral oxazolidinone-based diastereoselective installation of two hydroxy-bearing stereocenters, the Horner–Wadsworth–Emmons olefination to construct the full carbon skeleton, and the Shiina macrolactonization to establish the fourteen-membered macrolide structure. 相似文献
109.
This paper is concerned with the flapping characteristics and the structure dynamics of insect wings. The flapping behavior
of some insects is studied using a threedimensional motion analysis system. The experimental system is composed of two high-speed
video cameras, a motion grabber, and a personal computer. The three-dimensional representation of insect flapping can be gained
by the system. The extrinsic skeleton vibration produced by insect flapping is examined with the optical displacement detector
system. The structural properties of some insect wings are also studied by a three-dimensional, optical shape measurement
system. Some functional principles underlying insect wing design are revealed by the measurements of surface roughness and
flapping analysis. 相似文献
110.
Atsuo Yamada Kazuyuki Saka Makiko Uehara Sou Taminato Ryoji Kanno Fabrice Mauvy Claude Grenier 《Electrochemistry communications》2010,12(12):1690-1693
Electrode–electrolyte hetero-epitaxial systems for solid oxide fuel cells (SOFCs) with two different configuration of Nd2NiO4 + δ(110)//YSZ(100) and Nd2NiO4 + δ(100)//YSZ(110) were successfully fabricated by pulsed laser deposition. Thin films of Nd2NiO4 + δ approximately 20 nm thick were grown on a commercial single crystal of YSZ. The preferred two-dimensional diffusion paths of the oxide ions were perpendicular to the substrate for both configurations and showed oxygen reduction capability different from each other. This opens up new research direction focusing on the details of anisotropic catalytic activity of SOFC cathode depending on the crystalline surface. 相似文献