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91.
Ryoji Kobori Tomonori Ohba Takaomi Suzuki Taku Iiyama Sumio Ozeki Michio Inagaki Akihiro Nakamura Masato Kawai Hirofumi Kanoh Katsumi Kaneko 《Adsorption》2009,15(2):114-122
N2 adsorption isotherms of molecular sieve carbon were measured at 77 K and 303 K. The Ar adsorption isotherms of molecular
sieve carbon samples were also measured at 303 K. The grand canonical Monte Carlo (GCMC) simulation technique was applied
to calculate the N2 and Ar adsorption isotherms at 303 K using the ultramicropore volume determined by H2O adsorption. The comparative method of experimental and simulated isotherms of supercritical N2 and Ar at 303 K gave the width of the micropore mouth of the molecular sieve carbon, which can be applied to the ultramicropore
width determination for other noncrystalline porous solids. 相似文献
92.
93.
Akihiko Okumura Yasuaki Takada Susumu Watanabe Hiroaki Hashimoto Naoya Ezawa Yasuo Seto Yasuo Takayama Ryoji Sekioka Shintaro Yamaguchi Shintaro Kishi Takafumi Satoh Tomohide Kondo Hisayuki Nagashima Tomoki Nagoya 《Journal of the American Society for Mass Spectrometry》2016,27(7):1219-1226
We propose detecting a fragment ion (Ph2As+) using counter-flow introduction atmospheric pressure chemical ionization ion trap mass spectrometry for sensitive air monitoring of chemical warfare vomiting agents diphenylchloroarsine (DA) and diphenylcyanoarsine (DC). The liquid sample containing of DA, DC, and bis(diphenylarsine)oxide (BDPAO) was heated in a dry air line, and the generated vapor was mixed into the humidified air flowing through the sampling line of a mass spectrometer. Humidity effect on the air monitoring was investigated by varying the humidity of the analyzed air sample. Evidence of the in-line conversion of DA and DC to diphenylarsine hydroxide (DPAH) and then BDPAO was obtained by comparing the chronograms of various ions from the beginning of heating. Multiple-stage mass spectrometry revealed that the protonated molecule (MH+) of DA, DC, DPAH, and BDPAO could produce Ph2As+ through their in-source fragmentation. Among the signals of the ions that were investigated, the Ph2As+ signal was the most intense and increased to reach a plateau with the increased air humidity, whereas the MH+ signal of DA decreased. It was suggested that DA and DC were converted in-line into BDPAO, which was a major source of Ph2As+. 相似文献
94.
Hiroshi Mizukawa Tatsuhiro Nakajima Ryoji Seno Hiro-Fumi Yamada 《Letters in Mathematical Physics》2014,104(10):1317-1331
A Lie theoretic interpretation is given for some formulas of Schur functions and Schur Q-functions. Two realizations of the basic representation of the Lie algebra \({A^{(2)}_2}\) are considered; one is on the fermionic Fock space and the other is on the bosonic polynomial space. Via the boson–fermion correspondence, simple relations of the vacuum expectation values of fermions turn out to be algebraic relations of Schur functions. 相似文献
95.
Hiroyuki Hosomi Shigeru Ohba Yoshikatsu Ito 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):e144-e146
In the title four compounds, C13H11N·C7H4N2O6, (I), C15H15N·C7H4N2O6, (II), C16H17N·C7H4N2O6, (III), and C16H17N·C7H4N2O6, (IV), the donor and acceptor molecules are stacked alternately to form one‐dimensional columns. In (I), the N‐methyl group of the donor is nearly eclipsed with respect to one of the nitro groups of the neighboring acceptor in a column, whereas the N‐isopropyl, N‐butyl and N‐isobutyl groups are in anti positions with respect to one of the nitro groups of the neighboring acceptor in compounds (II)–(IV). 相似文献
96.
Yoshiyuki Kani Shigeru Ohba Mami Kunita Yuzo Nishida 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):e198-e198
The title mononuclear copper(II) complex, [CuCl(C18H26N4)]ClO4, shows a square‐pyramidal coordination with the diethylamino N atom at the apical position. Large anisotropies in the displacement parameters of the non‐H atoms of the ligand seem to be due to rotational disorder of the ClO4? anion. 相似文献
97.
Hiroyuki Hosomi Shigeru Ohba Yoshikatsu Ito 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):e260-e261
In the title two adducts, C3H12N22+·2C9H6NO4?, (I), and C6H16N22+·2C9H6NO4?, (II), hydrogen bonds between the diammonium and carboxylate ions form a two‐dimensional network parallel to the ab plane in (I) and one‐dimensional chains along the c axis in (II). The cyclohexanediammonium ion in (II) has a crystallographic twofold axis. 相似文献
98.
Yoshiyuki Kani Masanobu Tsuchimoto Shigeru Ohba 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):e193-e193
The title complex, [Cu2(C2H3O2)4(C7H6N2)2], shows a binuclear cage structure having an inversion centre. There are intramolecular N—H?O hydrogen bonds between the 7‐azaindole ligands and the bridging acetate O atoms. 相似文献
99.
Shigeru Ohba Makoto Eishima Hiroshi Seki 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):e555-e556
In the title compound, [Co(tpp)(NO2)(H2O)]·2dmf or [Co(C44H28N4)(NO2)(H2O)]·2C3H7NO, a distorted octahedral CoIII complex shows an orientational disorder such that the positions of the nitro and aqua ligands are exchanged. As a result, the averaged structure has an inversion centre at the Co atom. The dimethylformamide molecule also has a positional disorder. 相似文献
100.
Evaluation of the disintegration time of rapidly disintegrating tablets via a novel method utilizing a CCD camera 总被引:6,自引:0,他引:6
Morita Y Tsushima Y Yasui M Termoz R Ajioka J Takayama K 《Chemical & pharmaceutical bulletin》2002,50(9):1181-1186
Many kinds of rapidly disintegrating or oral disintegrating tablets (RDT) have been developed to improve the ease of tablet administration, especially for elderly and pediatric patients. In these cases, knowledge regarding disintegration behavior appears important with respect to the development of such a novel tablet. Ordinary disintegration testing, such as the Japanese Pharmacopoeia (JP) method, faces limitations with respect to the evaluation of rapid disintegration due to strong agitation. Therefore, we have developed a novel apparatus and method to determine the dissolution of the RDT. The novel device consists of a disintegrating bath and CCD camera interfaced with a personal computer equipped with motion capture and image analysis software. A newly developed RDT containing various types of binder was evaluated with this protocol. In this method, disintegration occurs in a mildly agitated medium, which allows differentiation of minor distinctions among RDTs of different formulations. Simultaneously, we were also able to detect qualitative information, i.e., morphological changes in the tablet during disintegration. This method is useful for the evaluation of the disintegration of RDT during pharmaceutical development, and also for quality control during production. 相似文献