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21.
Seiji Tsuzuki Kazumasa Honda Tadafumi Uchimaru Masuhiro Mikami Kazutoshi Tanabe 《Journal of the American Chemical Society》2002,124(1):104-112
A model chemistry for the evaluation of intermolecular interaction between aromatic molecules (AIMI Model) has been developed. The CCSD(T) interaction energy at the basis set limit has been estimated from the MP2 interaction energy near the basis set limit and the CCSD(T) correction term obtained by using a medium size basis set. The calculated interaction energies of the parallel, T-shaped,and slipped-parallel benzene dimers are -1.48, -2.46, and -2.48 kcal/mol, respectively. The substantial attractive interaction in benzene dimer, even where the molecules are well separated, shows that the major source of attraction is not short-range interactions such as charge-transfer but long-range interactions such as electrostatic and dispersion. The inclusion of electron correlation increases attraction significantly. The dispersion interaction is found to be the major source of attraction in the benzene dimer. The orientation dependence of the dimer interaction is mainly controlled by long-range interactions. Although electrostatic interaction is considerably weaker than dispersion interaction, it is highly orientation dependent. Dispersion and electrostatic interactions are both important for the directionality of the benzene dimer interaction. 相似文献
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Allen WH Bond IA Budding E Conway MJ Daniel A Fenton KB Fujii H Fujii Z Hayashida N Hibino K Honda M Humble JE Kabe S Kasahara K Kifune T Lythe GD Masaike A Matsubara Y Mitsui K Miura Y Mori M Muraki Y Nagano M Nakamura T Nishizawa M Morris PM Ogio S Saito T Sakata M Sato H Shimizu HM Spencer M Storey JR Tanimori T Teshima M Torii S Wadsworth A Watase Y Woodhams MD Yamamoto Y Yock PC Yuda T 《Physical review D: Particles and fields》1993,48(2):466-478
24.
James P. Kutney Toshio Honda Peter M. Kazmaier Norman J. Lewis Brian R. Worth 《Helvetica chimica acta》1980,63(2):366-374
The synthesis and conformational analysis of (3′R)-3-hydroxyleurosidine ( 5 ), (3′S)-3-hydroxyleurosidine ( 10 ), (3′S)-3-acetoxy-4′-deoxyleurosidine ( 15 ), (3′R)-3-acetoxy-4′-deoxyleurosidine ( 23 ), (3′R)-3-acetoxy-4′-deoxyvinblastine ( 16 ), (3′S)-3-acetoxy-4′-deoxyleurosidine ( 28 ) is discussed. 相似文献
25.
A home made column of commercially available iminodiacetate resin, Muromac A-1 (50–100 mesh) was used to concentrate rare earth elements (REEs) (15 elements: Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) in seawater. An automated low pressure flow analysis method with on-line column preconcentration/inductively coupled plasma mass spectrometry (ICP-MS) is described for the determination of REEs in seawater. Sample solutions (adjusted to pH of 3.0) passed through the column. After washing the column with water, the adsorbed elements were subsequently eluted into the plasma with 0.7 M nitric acid. Calibration curves were accomplished by means of purified artificial seawater with a sample loading time of 120 s. Detection limits (DLs) of the on-line column preconcentration/ICP-MS by eight replicate operations were between 0.040 and 0.251 pg ml−1 for REEs in the artificial seawater. The precision was less than 8.9% for REEs and one sample can be processed in 7 min using a 7 ml of sample. The proposed method was applied to determine REEs in coastal seawater of Hiroshima Bay, Japan. 相似文献
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Summary A simple method is described for the introduction of samples to a gas Chromatograph by means of a septumless port. The reproducibility and accuracy of the method have been shown by the analysis of ng quantities of estrone, estradiol, and estriol as the heptafluorobutyrates with an electron capture detector.
Zusammenfassung Die Einbringung von Proben in einen Gaschromatographen durch einen membranlosen Einspritzblock wurde beschrieben. Die Reproduzierbarkeit und Genauigkeit der so erhaltenen Ergebnisse wurde durch die Bestimmung von Nanogrammengen Östron, Östradiol und Östriol als Heptafluorobutyrate mit einem Elektroneneinfangdetektor erwiesen.相似文献
29.
Takeda Y Isai N Masuda T Honda G Takaishi Y Ito M Otsuka H Ashurmetov OA Khodzhimatov OK 《Chemical & pharmaceutical bulletin》2001,49(8):1039-1041
From the aerial parts of Phlomis spinidens, two new flavonol bisglycosides, phlomisflavosides A (1) and B (2), were isolated together with the known compounds, astragalin, isoquercitrin, lamiridoside, phlomoside A, shanzhiside methyl ester, 8-O-acetylshanzhiside methyl ester, phlorigidoside C, rodioloside (=salidroside), forsythoside B, citroside A and lariciresinol-4'-O-beta-D-glucoside. The structures of the new compounds were elucidated based on spectral and chemical evidence. 相似文献
30.
H. Honda A. Oshima H. Hinode M. Wakihara 《Journal of Thermal Analysis and Calorimetry》1992,38(8):1939-1945
Enthalpy increment HT-H289K measurements have been made on iron Chevrel phase sulphide Fe2Mo6S7.8, in the temperature range 300 to 500 K by the drop method using a hightemperature Calvet-type twin calorimeter. The first-order phase transition of this sulphide from a triclinic (low-temperature phase) to a rhombohedral (high-temperature phase) occurred at 375 K, and the enthalpy was evaluated to be 6.0 kJ/mol. The heat capacities of iron Chevrel phase sulphide Fe2Mo6S7.8 were also calculated before and after the phase transition.
Zusammenfassung Nach der Tropfenmethode wurden mittels eines Hochtemperaturdoppelkalorimeters vom Typ Calvet im Temperaturbereich 300–500 K an Fe2Mo6S7.8Messungen der Enthalpieinkremente HT-H298K durchgeführt. Die Phasenumwandlung erster Ordnung bei diesem Sulfid von der triklinen (Niedertemperaturphase) in die rhomboedrische (Hoch-temperaturphase) erfolgt bei 375 K und die Enthalpie erhielt man mit einem Wert von 6.0 kJ/mol. Die Wärmekapazitäten für Fe2Mo6S7.8 wurden sowohl vor als auch nach der Phasenumwandlung berechnet.相似文献