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181.
F−-induced decomposition of 3-[3-(tert-butyldimethylsiloxy)phenoxy]-3-phenyl-1,2-dioxetane (5c) yielded an intramolecular redox product (7b), whereas 3-phenoxy-3-(3-siloxyphenyl)-1,2-dioxetane (3) gave normal carbonyl fragments with intense light emission. An isomer (5a) gave light with normal decomposition by CIEEL, though the major process was one to yield an acyloin (7a). 相似文献
182.
Susumu Tajima Tadashige Azami Haruo Shizuka Toshikazu Tsuchiya 《Journal of mass spectrometry : JMS》1979,14(9):499-502
Single and double hydrogen atom transfers in reactions (1) and (2) in the mass spectra of ethyl benzoate, isopropyl benzoate, and isobutyl benzoate have been investigated with reference to the ortho effect: (1) [C6H5CO2R]+? → [C6H5CO2H]+? (m/z 122) + (R-H); (2) [C6H5CO2R]+? → [C6H5CO2H2]+ (m/z 123) + · (R-2H). It is demonstrated that the intermediate ion [C6H5CO2H2]+ has the protonated benzoic acid structure with the hydrogen atom on the carbonyl group. 相似文献
183.
A . Aihara T . Kawaguchi N. Miki T. Azami H. Sakamoto M. Okuma 《Experimental Mechanics》2017,57(8):1213-1224
This paper reports the development of a vibration monitoring system for wind turbine blades. This system is used to estimate the deflection at the tip blade on a wind turbine tower. Technical accidents of wind turbine blades have become increasingly common. Thus, regular monitoring of the blades is very important to prevent breakdowns, especially in cases when the blades begin to vibrate excessively. The monitoring system developed in this study satisfies two main objectives for practicality. First, our system is easy to install on existing wind turbines. Second, blade deflection is measured in real time. Our system can be operated using a few strain gages attached at the blade root, and the deflection is calculated based on the monitored stress. Thus, direct measurement of deflection at the blade tip is unnecessary. An estimation algorithm for this purpose is adopted based on the experimental modal analysis. This paper focuses on the evaluation of the estimation algorithm to investigate the feasibility of our system. Basic experiments were conducted using a simple blade model of a 300 W scaled wind turbine under rotation. Signals from the strain gages were acquired by a sensor network and sent to a computer through a wireless connection. The results show that the estimation accuracy is acceptably high. Therefore, we conclude that our proposed system is practical. 相似文献
184.
An all-fiber dynamic gain slope compensator is demonstrated, based on Mach–Zehnder interferometer design. Low voltage and electrical power are used to tune the attenuation slope via thermo-optic effect. A constant average insertion loss mode is demonstrated. 相似文献
185.
Mitsunori Oda Kazutaka Ogura Sayaka Kishi Kunihide Fujimori Noritaka Abe 《Tetrahedron letters》2007,48(26):4471-4475
The title azaazulene 3 was synthesized either by reaction of tropone with N-{(2-pyridyl)acetyl}pyridinium iodide in the presence of ammonium acetate or by palladium-catalyzed cross-coupling between 2-halo-1-azaazulene and 2-substituted pyridine. The compound shows relatively stronger basicity compared with 2,2′-bipyridyl. While 3 showed no emission from the S1 state but from the S2 state like azulene does, the protonated species of 3 exhibited emission from the S1 state. Cationic metal-dependent absorption and emission relating to complexation were also studied. 相似文献
186.
Yamada I Yamashita N Tani K Einishi T Saito M Fukumi K Nishii J 《Optics letters》2011,36(19):3882-3884
A mid-IR wire-grid polarizer with a 500 nm pitch was fabricated on a low toxic chalcogenide glass (Sb-Ge-Sn-S system) by the thermal imprinting of periodic grating followed by the thermal evaporation of Al metal. After imprinting, deposition of Al on the grating at an oblique angle produced a wire-grid polarizer. The fabricated polarizer showed polarization with TM transmittance greater than 60% at 5-9 μm wavelengths and an extinction ratio greater than 20 dB at 3.5-11 μm wavelengths. This polarizer with a high extinction ratio can be fabricated more simply and less expensively than conventional IR polarizers. 相似文献
187.
Lim JM Inoue M Sung YM Suzuki M Higashino T Osuka A Kim D 《Chemical communications (Cambridge, England)》2011,47(13):3960-3962
Conformational flexibility and balance between M?bius aromatic and Hückel antiaromatic conformers in [28]hexaphyrins depend on N-fused structure and meso-aryl substituents, revealed by various spectroscopic methods. In particular, the existence of the two conformers has been confirmed for singly-N-fused [28]hexaphyrins by femtosecond time-resolved transient absorption spectroscopy. 相似文献
188.
Mitsunori Honda Kenta NakaeToshiaki Nishizawa Mitsuhiro SudaKo-Ki Kunimoto Masahito Segi 《Tetrahedron》2011,67(49):9500-9508
The reaction of silylcyclopropyl bromides with dichloromethyl methyl ether in the presence of n-butyllithium is investigated. Under basic reaction conditions, the corresponding cyclopropylidene derivatives are exclusively obtained. The resulting cyclopropylidene compounds are subjected to protonolysis or trapping with electrophiles in a one-pot to give the cyclopropyl silyl ketone derivatives in good yields. Acidic treatment of derived cyclopropyl silyl ketone allows isomerization to give the thermodynamically favorable trans form exclusively. 相似文献
189.
Takekazu Ishida Kohei Arai Yukio Akita Mitsunori Miyanari Yusuke Minami Tsutomu Yotsuya Masaru Kato Kazuo Satoh Mayumi Uno Hisashi Shimakage Shigehito Miki Zhen Wang 《Physica C: Superconductivity and its Applications》2010,470(19):730-733
The nanofabrication of superconductors yields various interesting features in superconducting properties. A variety of different imaging techniques have been developed for probing the local superconducting profiles. A scanning pulsed laser microscope has been developed by the combination of the XYZ piezo-driven stages and an optical fiber with an aspheric focusing lens. The scanning laser microscope is used to understand the position-dependent properties of a superconducting MgB2 stripline of length 100 μm and width of 3 μm under constant bias current. Our results show that the superconducting stripline can clearly be seen in the contour image of the scanning laser microscope on the signal voltage. It is suggested from the observed image that the inhomogeneity is relevant in specifying the operating conditions such as detection efficiency of the sensor. 相似文献
190.