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61.
Yoshihisa Kurasawa Tae Kawano Ritsuko Katoh Atsushi Takada Ho Sik Kim Yoshihisa Okamoto 《Journal of heterocyclic chemistry》1992,29(5):1337-1339
The reaction of 6-chloro-2-(1-methylhydrazino)quinoxaline 4-oxide 1 or 6-chloro-2-(1-methylhydrazino)-quinoxaline 5 with phenyl isothiocyanate under reflux in N,N-dimethylformamide gave 7-chloro-3-methyl-1,2,4-triazolo[4,3-a]quinoxalin-3-ium-1-thioate 4 , which was also obtained by refluxing of 6-chloro-2-[1-methyl-2-(N-phenylthiocarbamoyl)hydrazino]quinoxaline 4-oxide 2b or 6-chloro-2-[1-methyl-2-(N-phenylthiocarbamoyl)hydrazino]quinoxaline 6 in N,N-dimethylformamide. 相似文献
62.
M. Yagi T. Mitsugashira I. Satoh M. Hara Y. Shiokawa K. Inoue K. Masumoto S. Suzuki 《Journal of Radioanalytical and Nuclear Chemistry》1989,137(6):421-429
As a new fact, the neutron emission from the d-d nuclear fusion reaction in a SiO2–D2 system has been confirmed as well as that in the Ti–D2 system. By using a liquid scintillation detector, the neutron emissions from 8 sample materials consisted of SiO2, in which a small amount of deuterium was adsorbed chemically on the surface layer, were measured in the range of temperature between liquid nitrogen temperature and 400 °C. As a result, it was demonstrated that the neutron-emission reactions take place predominantly on the surface layer of sample material. 相似文献
63.
We have investigated tension wood cellulose obtained from Populus maximowiczii using X-ray diffraction at temperatures from room temperature to 250 °C. Three equatorial and one meridional d-spacings showed a gradual linear increase with increasing temperature. For temperatures above 180 °C, however, the equatorial
d-spacing increased dramatically. Thus, the linear and volume thermal expansion coefficients (TECs) below 180 °C were determined
from the d-spacings. The linear TECs of the a-, b-, and c-axes were: α
a
= 13.6 × 10−5 °C−1, α
b
= −3.0× 10−5 °C−1, and α
c
=0.6× 10−5 °C−1, respectively, and the volume TEC was β = 11.1× 10−5 °C−1. The anisotropic thermal expansion in the three coordinate directions was closely related to the crystal structure of the
wood cellulose, and it governed the macroscopic thermal behavior of solid wood. 相似文献
64.
Ferdy S. Rondonuwu Kyosuke Yokoyama Ritsuko Fujii Yasushi Koyama Richard J. Cogdell Yasutaka Watanabe 《Chemical physics letters》2004,390(4-6):314-322
Subpicosecond time-resolved absorption spectra were recorded, in the visible and near-infrared regions, for the LH2 antenna complexes from Rhodobacter sphaeroides G1C, Rhodobacter sphaeroides 2.4.1, Rhodospirillum molischianum, and Rhodopseudomonas acidophila. The efficiencies of carotenoid-to-bacteriochlorophyll singlet-energy transfer through the 11Bu+, 11Bu−, and 21Ag− channels in the LH2 complex were determined to be 48%, 19% and 22% in Rhodobacter sphaeroides G1C; 46%, 18% and 20% in Rhodobacter sphaeroides 2.4.1; 48%, 2% and 1% in Rhodospirillum molischianum; and 48%, 2%, 4% in Rhodopseudomonas acidophila. Sums of efficiencies through the three channels in the four LH2 complexes, 88%, 84%, 51% and 54%, nicely correlate with the efficiencies that were determined by comparison of the absorption and fluorescence-excitation spectra, 92%, 89%, 53% and 56%. 相似文献
65.
Preparation of thin films of lanthanide (Ln) sulfides has been studied by the chemical vapor deposition (CVD) method, using metal -diketonato chelates with 2,2,6,6-tetramethyl-3,5-heptanedione and reactant H2S gas as starting materials. Two kinds of sulfides, Ln2O2S oxysulfides and EuS monosulfide, were obtained as thin films at temperatures as low as 390–570 °C. The CVD method was confirmed to be suited for the above purpose. 相似文献
66.
The electrodeposition of uranium and trace quantities of239Pu,234Th,144Ce on a stainless steel disk has been investigated from 0.5–2.0M NaOH and the two-phase system: extract of actinides in TBP-aqueous solution of NaOH. The electrodeposition yield of the above elements reaches 98–100% in 40 min of electrolysis with current density 0.4–0.5 A/cm2. The presence of 0.5M Na2CO3, 2.0M NaNO3, 2.0M NaNO2, 0.2M NaF in alkaline solutions does not decrease the electrodeposition yield. The electrodeposited films meet all the requirements of -spectrometry. The uranium oxidation states (V) and (IV) have been determined in the electrodeposited films. 相似文献
67.
Ritsuko Shiokawa Xiao‐Pen Lee Miho Yamada Masaya Fujishiro Hiroshi Sakamaki Chika Hasegawa Hiroo Ishida Kenichiro Ikeda Ken‐ichi Fujita Shigehiro Iwabuchi Hidetoshi Onda Takeshi Kumazawa Yasutsuna Sasaki Keizo Sato Takaaki Matsuyama 《Rapid communications in mass spectrometry : RCM》2019,33(24):1906-1914
68.
Tokunaga Y Homma Y Kambe S Aoki D Sakai H Yamamoto E Nakamura A Shiokawa Y Walstedt RE Yasuoka H 《Physical review letters》2005,94(13):137209
In order to elucidate the nature of the exotic ordered phase of NpO2 below T(0)=26 K, we have initiated the first 17O-NMR measurements on this system. From the 17O-NMR spectrum, the occurrence of two inequivalent oxygen sites has been confirmed below T0. It has also been shown that the characteristic features of the hyperfine interaction at the oxygen sites are well explained by invoking a hyperfine interaction with field-induced antiferromagnetic moments which appear as a result of the triple-q antiferroquadrupolar order. The NMR findings strongly support the occurrence of the longitudinal triple-q multipole structure in NpO2. 相似文献
69.
Masataka Kubo Hirozumi Takeuchi Tomoyuki Ohara Takahito Itoh Ritsuko Nagahata 《Journal of polymer science. Part A, Polymer chemistry》1999,37(13):2027-2033
Living anionic polymerization of styrene was carried out in benzene at room temperature using 1-(3-lithiopropyl)-4-methyl-2,6,7-trioxabicyclo[2.2.2]octane and 2,2,5,5-tetramethyl-1-(3-bromopropyl)-1-aza-2,5-disilacyclopentane as an initiator and terminator, respectively, to obtain α-2,2-bis(hydroxymethyl)propoxycarbonyl, ω-amino heterodifunctional polystyrene. It was hydrolyzed to α-carboxyl, ω-amino heterodifunctional polystyrene which gave a well-defined cyclic polystyrene by the intramolecular cyclization under high dilution conditions. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2027–2033, 1999 相似文献
70.
Yoshihisa Kurasawa Ritsuko Katoh Fumiko Mori Minori Fukuchi Megumi Okamoto Atsushi Takada Ho Sik Kim Yoshihisa Okamoto 《Journal of heterocyclic chemistry》1992,29(4):1009-1011
The reaction of 6-chloro-2-hydrazinoquinoxaline 4-oxide 6 with ethyl 2-(ethoxymethylene)-2-cyanoacetate or (1-ethoxyethylidene)malononitrile gave 2-(5-amino-4-ethoxycarbonylpyrazol-1-yl)-6-chloroquinoxaline 4-oxide 7a or 2-(5-amino-4-cyano-3-methylpyrazol-1-yl)-6-chloroquinoxaline 4-oxide 7b , respectively. The reaction of compound 7a or 7b with dimethyl acetylenedicarboxylate resulted in the 1,3-dipolar cycloaddition reaction and then ring transformation to afford 4-(5-amino-4-ethoxycarbonylpyrazol-1-yl)-8-chloro-1,2,3-trismethoxycarbonylpyrrolo[1,2-α]quinoxaline 8a or 4-(5-amino-4-cyano-3-methylpyrazol-1-yl)-8-chloro-1,2,3-trismethoxycarbonylpyrrolo[1,2-α]quinoxaline 8b , respectively. 相似文献