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61.
Hanai T 《Journal of chromatographic science》2006,44(5):247-252
A quantitative analysis of the retention of aromatic acid derivatives in reversed-phase liquid chromatography (RPLC) is conducted using a molecular mechanics calculation in the CAChe program. The molecular interaction energy value is calculated by subtracting the energy value of the complex from the sum of energy values of a model phase and an analyte. Several model phases are constructed, and the feasibility of applying the method to a variety of compounds is examined based on improving the contact surface area and the capability of computer software and hardware. Interaction energy values are calculated for both molecular and ionic forms. The predicted retention factors of partially ionized acids obtained using a combination of dissociation constants correlated well with the values measured by RPLC with pH-controlled eluents. 相似文献
62.
63.
64.
Hanai K Kuwae A Takai T Senda H Kunimoto KK 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2001,57(3):513-519
The IR and Raman spectra of the two polymorphic forms (58 degree- and 68 degree-forms) of cis-cinnamic acid were measured, and the spectral differences discussed on the basis of the crystal structures of the two forms. The IR bands related to the COOH group differ in the frequencies and band shape, reflecting differences in the hydrogen bonding between the two modifications. These spectra were compared with those of trans-cinnamic acid. The IR, Raman, and NMR spectra of the isotopic compounds, including the deuterated and 13C analogs of the cis and trans acids, were also recorded in the solid state and in solution to confirm the spectral assignments. 相似文献
65.
Shimizu A Suzuki Y Torihata A Hanai R Saito Y Tori M Gong X Kuroda C 《Natural product communications》2012,7(4):431-434
Two samples of Ligularia kanaitzensis collected in the Shizhongshan Mountain region of Yunnan Province, as well as one sample collected in Sichuan Province, were analyzed with regard to root constituents and neutral DNA sequences. The two Shizhongshan samples were found to be different from each other and from other samples analyzed previously, indicating that the intra-specific diversity in the species was highly complex. 相似文献
66.
Morita Kentato Motoyama Keiichi Kuramoto Ayako Onodera Risako Higashi Taishi 《Journal of inclusion phenomena and macrocyclic chemistry》2021,100(3-4):169-175
Journal of Inclusion Phenomena and Macrocyclic Chemistry - In recent years, functional materials using cyclodextrin (CD)-based polyrotaxanes have attracted considerable attention, and... 相似文献
67.
A theoretical formula of dielectric relaxation in a form of complex relative permittivity is derived for dilute suspensions of spherical particles of two kinds on the basis of the Maxwell-Wagner theory of interfacial polarization. Another theoretical formula is derived further for concentrated suspensions of spheres of two kinds on condition that the formula derived above holds for the infinitesimally increasing process in concentration of the dispersed spheres. Furthermore a theoretical formula is derived for concentrated suspensions of shelled spheres of two kinds as the extension of the formula for concentrated suspensions. By use of the theoretical formulas proposed, values of the permittivities and the conductivities of the two-component suspensions were calculated for some examples with different sets of phase parameters. Results of the numerical calculation demonstrates dielectric relaxation profiles full of variety and characteristic of the suspensions containing two kinds of spheres covered with or without shells. 相似文献
68.
A dielectric theory was developed to analyze dielectric relaxation of a system in which biological cells are settling perpendicular and parallel to electrode planes. The theory predicts that the dielectric relaxation intensity () increases markedly with increasing time when the settling direction is perpendicular to electrode planes, whereas is less sensitive to the sedimentation in a direction parallel to electrode planes. These theoretical expectations agreed well with the experimental results obtained with sheep erythrocytes. Analysis based on this theory provided the sedimentation rate of sheep erythrocytes, the results being in agreement with those obtained by the conventional method. 相似文献
69.
Kristo Michael J. Williams Ross Gaffney Amy M. Kayzar-Boggs Theresa M. Schorzman Kerri C. Lagerkvist Petra Vesterlund Anna Ramebäck Henrik Nelwamondo Aubrey N. Kotze Deon Song Kyuseok Lim Sang Ho Han Sun-Ho Lee Chi-Gyu Okubo Ayako Maloubier Didier Cardona Danièle Samuleev Pavel Dimayuga Ike Varga Zsolt Wallenius Maria Mayer Klaus Loi Elaine Keegan Elizabeth Harrison Jennifer Thiruvoth Sangeeth Stanley Floyd E. Spencer Khal J. Tandon Lav 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(2):425-434
Journal of Radioanalytical and Nuclear Chemistry - In a recent international exercise, 10 international nuclear forensics laboratories successfully performed radiochronometry on three low enriched... 相似文献
70.
Sol-gel method was applied to prepare CdS
x
Se1–x
microcrystals doped glasses. Gels were synthesized through the hydrolysis of Si(OC2H5)4, CdSeO4, and NH4SCN, and then heated in H2-N2 gas atmosphere to precipitate CdS
x
Se1–x
microcrystals in the glasses. The composition of crystals was preliminarily determined during the synthesis of the gels. The optical band gap energies were blue shifted compared with those of the bulk crystals due to the quantum-sized confinement effect. 相似文献