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101.
102.
Masami Sakamoto Kazuya Yoshiwara Fumitoshi Yagishita Wataru Yoshida Takashi Mino Tsutomu Fujita 《Research on Chemical Intermediates》2013,39(1):385-395
The irradiation of methyl 2- and 3-chromonecarboxylate in the presence of various alkenes afforded cyclobutane type adducts, whose structures were established by X-ray structural analysis. Methyl 2-chromonecarboxylate showed higher photochemical reactivity than methyl 3-chromonecarboxylate, in which endo adducts were yielded as major products. 相似文献
103.
Prof. Dr. Tsutomu Ishi-i Honoka Tanaka Rihoko Kichise Christopher Davin Takaaki Matsuda Dr. Naoya Aizawa Dr. In Seob Park Prof. Dr. Takuma Yasuda Taisuke Matsumoto 《化学:亚洲杂志》2021,16(15):2136-2145
The regulation of multicolor fluorescence changes in mechanochromic fluorescence (MCF) remains a challenging task. Herein, we report the regulation of MCF using a donor-acceptor structure. Two crystal polymorphs, BTD-pCHO(O) and BTD-pCHO(R) produced by the introduction of formyl groups to an MCF dye, respond to a mechanical stimulus, allowing a three-color fluorescence change. Specifically, the orange-colored fluorescence of the metastable BTD-pCHO(O) polymorph changed to a deep-red color in the amorphous-like state to finally give a red color in the stable BTD-pCHO(R) polymorph. This change occurred by mechanical grinding followed by vapor fuming. The two different crystal packing patterns were selectively regulated by the electronic effect of the introduced functional groups. The two types of selectively formed crystals in BTD(F)-pCHO bearing fluorine atoms, and BTD(OMe)-pCHO bearing methoxy groups, respond to mechanical grinding, allowing for the regulation of multicolor MCL from a three-color change to two different types of two-color changes. 相似文献
104.
Yoshiki K Kanamaru R Ryosuke K Hashimoto M Hashimoto N Araki T 《Optics letters》2007,32(12):1680-1682
We developed a compact polarization-mode converter for microscopy to control three-dimensional polarization at the focus. The converter consisted of two homogeneously aligned liquid-crystal spatial light modulators with eight independently controllable electrodes (segments), and a quarter-waveplate. The converter converted a linearly polarized beam to three polarization modes: two orthogonal linear polarizations and a pseudo-radial polarization. We applied the converter to second-harmonic-generation microscopy and demonstrated the detection of three-dimensional molecular orientation. 相似文献
105.
Asobe M Tadanaga O Umeki T Yanagawa T Nishida Y Magari K Suzuki H 《Optics letters》2007,32(23):3388-3390
We propose a novel quasi-phase-matched (QPM) device that can generate unequally spaced multiple wavelengths. Unequally spaced multiple QPM peaks can be obtained by employing the optimized phase modulation of a periodic domain structure. We fabricated a LiNbO3 waveguide device for 3.2-3.4 microm band difference frequency generation based on the design. Using the multiple mid-infrared outputs, we demonstrate the detection of multiple hydrocarbon gases, namely, methane, ethylene, and ethane. 相似文献
106.
Enhancement of Solar Hydrogen Evolution from Water by Surface Modification with CdS and TiO2 on Porous CuInS2 Photocathodes Prepared by an Electrodeposition–Sulfurization Method 下载免费PDF全文
Dr. Jiao Zhao Dr. Tsutomu Minegishi Li Zhang Dr. Miao Zhong Gunawan Dr. Mamiko Nakabayashi Dr. Guijun Ma Dr. Takashi Hisatomi Dr. Masao Katayama Prof. Dr. Shigeru Ikeda Prof. Dr. Naoya Shibata Prof. Dr. Taro Yamada Prof. Dr. Kazunari Domen 《Angewandte Chemie (International ed. in English)》2014,53(44):11808-11812
Porous films of p‐type CuInS2, prepared by sulfurization of electrodeposited metals, are surface‐modified with thin layers of CdS and TiO2. This specific porous electrode evolved H2 from photoelectrochemical water reduction under simulated sunlight. Modification with thin n‐type CdS and TiO2 layers significantly increased the cathodic photocurrent and onset potential through the formation of a p–n junction on the surface. The modified photocathodes showed a relatively high efficiency and stable H2 production under the present reaction conditions. 相似文献
107.
Soliman Mohamed A. Mohamed Nader M. A. Takamiya Koichi Sekimoto Shun Inagaki Makoto Oki Yuichi Ohtsuki Tsutomu 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(3):1099-1107
Journal of Radioanalytical and Nuclear Chemistry - To assess the capability of Kyoto University Research Reactor to supply the domestic needs of medical isotopes, its neutron flux has been fully... 相似文献
108.
Inagaki Makoto Sekimoto Shun Tadokoro Takahiro Ueno Yuichiro Kani Yuko Ohtsuki Tsutomu 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(2):681-686
Journal of Radioanalytical and Nuclear Chemistry - Amount estimation of production of 99Mo required for medical applications was carried out by utilizing an electron linear accelerator with... 相似文献
109.
Jin Su Takashi Hisatomi Tsutomu Minegishi Kazunari Domen 《Angewandte Chemie (International ed. in English)》2020,59(33):13800-13806
Most CdTe photoanodes and photocathodes show positive and negative photocurrent onset potentials for water oxidation and reduction, respectively, and are thus unable to drive photoelectrochemical (PEC) water splitting without external applied biases. Herein, the activity of a CdTe photoanode having an internal p‐n junction during PEC water oxidation was enhanced by applying a CdCl2 annealing treatment together with surface modifications. The resulting CdTe photoanode generated photocurrents of 1.8 and 5.4 mA cm?2 at 0.6 and 1.2 VRHE, respectively, with a photoanodic current onset potential of 0.22 VRHE under simulated sunlight (AM 1.5G). The CdCl2 annealing increased the grain sizes and lowered the density of grain boundaries, allowing more efficient charge separation. Consequently, a two‐electrode tandem PEC cell comprising a CdTe‐based photoanode and photocathode split water without any external bias at a solar‐to‐hydrogen conversion efficiency of 0.51 % at the beginning of the reaction. 相似文献
110.