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941.
Kazuhiro Kobayashi Hiroo Hashimoto Teruhiko Suzuki Hisatoshi Konishi 《Helvetica chimica acta》2011,94(11):2002-2009
An efficient method for the synthesis of 2‐aryl‐2,3‐dihydro‐3‐sulfanyl‐1H‐isoindol‐1‐ones 1 via Pummerer‐type cyclization of N‐aryl‐2‐(sulfinylmethyl)benzamides 2 is described. Thus, treatment of these sulfinyl‐benzamides 2 , easily prepared from 2‐(bromomethyl)benzoates 3 in three steps, with Ac2O at ca. 100° resulted in the formation of the desired isoindolones 1 in generally good yields. 相似文献
942.
Hashimoto S Takazawa Y Fushimi A Tanabe K Shibata Y Ieda T Ochiai N Kanda H Ohura T Tao Q Reichenbach SE 《Journal of chromatography. A》2011,1218(24):3799-3810
We successfully detected halogenated compounds from several kinds of environmental samples by using a comprehensive two-dimensional gas chromatograph coupled with a tandem mass spectrometer (GC×GC-MS/MS). For the global detection of organohalogens, fly ash sample extracts were directly measured without any cleanup process. The global and selective detection of halogenated compounds was achieved by neutral loss scans of chlorine, bromine and/or fluorine using an MS/MS. It was also possible to search for and identify compounds using two-dimensional mass chromatograms and mass profiles obtained from measurements of the same sample with a GC×GC-high resolution time-of-flight mass spectrometer (HRTofMS) under the same conditions as those used for the GC×GC-MS/MS. In this study, novel software tools were also developed to help find target (halogenated) compounds in the data provided by a GC×GC-HRTofMS. As a result, many dioxin and polychlorinated biphenyl congeners and many other halogenated compounds were found in fly ash extract and sediment samples. By extracting the desired information, which concerned organohalogens in this study, from huge quantities of data with the GC×GC-HRTofMS, we reveal the possibility of realizing the total global detection of compounds with one GC measurement of a sample without any pre-treatment. 相似文献
943.
Thu Lan Nguyen Takashi Yano Huy Quang Nguyen Tsuyoshi Nishimura Hiroaki Fukushima Tetsumi Sato Takashi Morihara Yoritaka Hashimoto 《Applied Acoustics》2011,(11):814-822
To formulate Vietnamese and global noise policies, social surveys on community response to aircraft noise and combined noise from aircraft and road traffic were carried out in Ho Chi Minh City from August to September 2008 and in Hanoi from August to September 2009. In total, 1562 and 1397 responses were obtained in Ho Chi Minh City and Hanoi, respectively. The aircraft noise was measured for seven successive days, and the combined noise was measured for 24 h. Aircraft and combined noise exposures ranged from 53 to 71 dB and 73 to 83 dB Lden in Ho Chi Minh City and from 48 to 61 dB and 70 to 82 dB Lden in Hanoi, respectively. The dose–response curve for aircraft noise for Vietnam was established and fitted onto the curve for the European Union. For the same noise exposure, the aircraft noise annoyance in Hanoi was higher than that in Ho Chi Minh City because of the lower background noise level in Hanoi. 相似文献
944.
Hiroyuki Takano Koichi IzumiyaNaokazu Kumagai Koji Hashimoto 《Applied Surface Science》2011,257(19):8171-8176
The active catalysts for methane formation from the gas mixture of CO2 + 4H2 with almost 100% methane selectivity were prepared by reduction of the oxide mixture of NiO and ZrO2 prepared by calcination of aqueous ZrO2 sol with Sm(NO3)3 and Ni(NO3)2. The 50 at%Ni-50 at%(Zr-Sm oxide) catalyst consisting of 50 at%Ni-50 at%(Zr + Sm) with Zr/Sm = 5 calcined at 650 or 800 °C showed the highest activity for methanation. The active catalysts were Ni supported on tetragonal ZrO2, and the activity for methanation increased by an increase in inclusion of Sm3+ ions substituting Zr4+ ions in the tetragonal ZrO2 lattice as a result of an increase in calcination temperature. However, the increase in calcination temperature decreased BET surface area, metal dispersion and hydrogen uptake due to grain growth. Thus, the optimum calcination temperature existed. 相似文献
945.
H. Watanabe K. YamaguchiA. Odahara T. SumikamaS. Nishimura K. YoshinagaZ. Li Y. MiyashitaK. Sato L. PróchniakH. Baba J.S. BerrymanN. Blasi A. Bracco F. Camera J. ChibaP. Doornenbal S. GoT. Hashimoto S. HayakawaC. Hinke N. HinoharaE. Ideguchi T. IsobeY. Ito D.G. JenkinsY. Kawada N. KobayashiY. Kondo R. KrückenS. Kubono G. Lorusso T. NakanoT. Nakatsukasa M. Kurata-NishimuraH.J. Ong S. OtaZs. Podolyák H. SakuraiH. Scheit K. SteigerD. Steppenbeck K. SugimotoK. Tajiri S. TakanoA. Takashima T. TeranishiY. Wakabayashi P.M. WalkerO. Wieland H. Yamaguchi 《Physics letters. [Part B]》2011,704(4):270-275
946.
Y. Hashimoto M. Kitaoka T. Yoshida S. Hasegawa 《Applied physics. B, Lasers and optics》2011,103(2):339-344
We report the observation of sympathetically cooled 43Ca+ (natural abundance 0.135%) in a linear ion trap utilizing simultaneously trapped isotope ions as coolant. We investigated
different possibilities of realizing efficient sympathetic cooling and observed the peaks of the hyperfine transitions of
43Ca+ under various experimental conditions. 相似文献
947.
Hirobumi Shibata Shin-ichi Ohshika Taku Ogura Satoshi Watanabe Keishi Nishio Hideki Sakai Masahiko Abe Kazuaki Hashimoto Mutsuyoshi Matsumoto 《Journal of photochemistry and photobiology. A, Chemistry》2011,217(1):136-140
Mesostructured titania particles modified with phthalocyanine (Pc) were prepared by using molecular self-assemblies of cetyltrimethylammonium bromide (CTAB) with solubilized Pc as a template. Low-angle X-ray diffraction pattern and transmission electron microscopy (TEM) image clearly show the formation of Pc/titania particles with hexagonal mesopore structures. Diffuse reflectance UV–vis spectrum and fluorescence spectrum of Pc/titania indicate that Pc molecules in the pores are in a monomeric state. In addition, Pc/titania particles have photocatalytic activity under visible light irradiation (>610 nm) due to the reduction reaction by the electrons transferred from Pc to titania. 相似文献
948.
949.
Ryuhi Kanehara Akio Tonouchi Katsuhiro Konno Masaru Hashimoto 《Molecules (Basel, Switzerland)》2021,26(14)
A series of cyclohumulanoids, i.e., tricocerapicanols A–C (1a–1c), tricoprotoilludenes A (2a) and B (3), tricosterpurol (4), and tricoilludins A–C (5–7) were isolated along with known violascensol (2b) and omphadiol (8) from the culture broth of Daedaleopsis tricolor, an inedible but not toxic mushroom. The structures were fully elucidated on the basis of NMR spectroscopic analysis, and the suggested relative structures were confirmed via density functional theory (DFT)-based chemical shift calculations involving a DP4 probability analysis. In the present study, the 1H chemical shifts were more informative than the 13C chemical shifts to distinguish the diastereomers at C-11. The absolute configurations of 1–5 were determined by comparing the experimental and calculated electronic circular dichroism (ECD) spectra. For 6 and 7, the same chirality was assigned according to their biosynthetic similarities with the other compounds. The successful assignment of some Cotton effects was achieved by utilizing DFT calculations using simple model compounds. The plausible biosynthesis of 1–7 was also discussed on the basis of the structural commonality and general cyclohumulanoid biosynthesis. Compounds 2a and 5 were found to simultaneously induce hyphal swelling and branching at 5.0 μg/mL against a test fungus Cochliobolus miyabeanus. 相似文献
950.
Hideki Hashimoto Mutsunori Yagiura Shinji Imahori Toshihide Ibaraki 《Annals of Operations Research》2013,204(1):171-187
Vehicle routing and scheduling problems have a wide range of applications and have been intensively studied in the past half century. The condition that enforces each vehicle to start service at each customer in the period specified by the customer is called the time window constraint. This paper reviews recent results on how to handle hard and soft time window constraints, putting emphasis on its different definitions and algorithms. With these diverse time windows, the problem becomes applicable to a wide range of real-world problems. 相似文献