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781.
Yamazaki S Yao M Fujiwara N Siroma Z Yasuda K Ioroi T 《Chemical communications (Cambridge, England)》2012,48(36):4353-4355
A Rh porphyrin on carbon black was shown to catalyze the electro-oxidation of several aliphatic alcohols (ethanol, 1-propanol, and 2-propanol) and benzyl alcohols. The overpotentials for alcohol oxidation were very low. The reaction mechanism and substrate specificity are discussed. 相似文献
782.
The effectiveness of the mechanism of surface tension to analyze the host-guest interaction was demonstrated by measuring the unbinding force of the beta-Cyclodextrin (CyD)--adamantane molecules in a liquid environment at the single-molecule level. The contribution of the solvophobic effect was quantitatively distinguished from the intrinsic van der Waals force, and the effective length that produces the detected force through employing the notion of surface tension was determined to be , which is consistent with the perimeter of the adamantane molecule, . Specific strong interaction of water molecules was also confirmed on the nanoscale. 相似文献
783.
Toyota T Tsuha H Yamada K Takakura K Yasuda K Sugawara T 《Langmuir : the ACS journal of surfaces and colloids》2006,22(5):1976-1981
Adding an artificial bolaamphiphile to a dispersion of giant multilamellar vesicles (GMVs) made of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC) induced a cup-shaped deformation in GMVs accompanied by partial extrusion of the inner vesicle; thereafter, the deformed vesicles returned to their original shape. On the other hand, when the artificial bolaamphiphile together with a surfactant was added to the vesicular dispersion, these deformation and reformation dynamics were transmitted from the outer membranes in GMVs to the inner membranes until an intact inner vesicle was extruded out of the outer membrane. The microscopic aspects of these processes were investigated using amphiphiles tagged with individual fluorophores. 相似文献
784.
Fujitsuka M Cho DW Shiragami T Yasuda M Majima T 《The journal of physical chemistry. B》2006,110(19):9368-9370
The S(2) state properties of Sb-tetraphenylporphyrin (SbTPP) derivatives were investigated using subpicosecond spectroscopic methods. The S(2) fluorescence of various SbTPP derivatives was observed for the first time. It was revealed that the S(2) fluorescence lifetime changed depending on the donor-ability of the ligand because of the contribution of the charge separation to the S(2) excited SbTPP, which was confirmed by transient absorption spectroscopy. 相似文献
785.
A simple method for the determination of magnesium stearate in capsule- or tablet-type supplements was developed. Free stearic acid in the sample was removed by extraction with tetrahydrofuran. The remaining stearate was converted to stearic acid by reaction with a cation-exchange resin. The resulting stearic acid was determined by gas chromatography with a polar column. Esters of stearic acid were not converted to stearic acid and would not cause a positive error in the amount of stearate. The amount of magnesium stearate was calculated based on the stearic acid concentration thus obtained. Magnesium stearate levels in 5 out of 25 supplements exceeded 2500 microg/g, which indicated the possible admixture of magnesium stearate. 相似文献
786.
Synergistic hybrid catalyst for cyclic carbonate synthesis: remarkable acceleration caused by immobilization of homogeneous catalyst on silica 总被引:3,自引:0,他引:3
Takahashi T Watahiki T Kitazume S Yasuda H Sakakura T 《Chemical communications (Cambridge, England)》2006,(15):1664-1666
The catalytic activity of phosphonium salts towards cyclic carbonate synthesis from propylene oxide and CO2 has been enormously enhanced by their immobilization onto silica that itself has no catalytic activity. 相似文献
787.
788.
By using the many-particle Green's function (GF) the extension of the fragment molecular orbital (FMO) method by Kitaura et al. [Chem. Phys. Lett. 313, 701 (1999)] is proposed. It is shown that the partial summation of the cluster expansion of GF reproduces the same extrapolation formula as that of FMO. Therefore we can determine the excitation energy, the transition moment, and the linear response of a molecule from GF approximated with the FMO procedure. It is also shown that no wave function exists which is consistent to the FMO results. The perturbation expansion in which the self-consistent charge approximation defines the unperturbed state is reported. By using it the three-body effects missing in the pair approximation of FMO are analyzed and the corrections to the energy and the reduced density matrices are proposed. In contrast to the previous works these new corrections are not expressed as the addition or the subtraction of the energies of fragments. They are size extensive and require only the quantities available by the FMO calculation. The accuracy of these corrections is validated with the extended Hubbard model and the several test molecules. 相似文献
789.
Fujihara J Yasuda T Iida R Kimura-Kataoka K Soejima M Koda Y Kato H Panduro A Yuasa I Takeshita H 《Electrophoresis》2010,31(21):3552-3557
Several SNPs in the deoxyribonuclease I-like 1 (DNase 1L1) and DNase 1L2 were investigated. In the present study, the genotype distributions of three synonymous SNPs (V59V, rs1050095; P67P, rs1130929; A277A, rs17849495) in the DNase 1L1 gene and four non-synonymous SNPs, V122I (rs34952165), Q170H (rs6643670), and D227A (rs5987256) in the DNase 1L1 gene, as well as D197A (rs62621282) in the DNase 1L2 gene were investigated in 13 populations. In all the populations, no variation was found in four SNPs (V59V, Q170H, D227A, and A277A) in DNASE1L1 or in D197A in DNASE1L2. As for V122I, only the German population showed a low degree of polymorphism. The SNP V122I in DNASE1L1 was monoallelic for the G-allele in all of the Asian and African populations examined, with no polymorphism being evident. Since the A-allele in SNP V122I was distributed in only the Caucasian populations, not in the other ethnic groups, it was confirmed that the A-allele in SNP V122I was Caucasian-specific. On the other hand, only P67P in DNASE1L1 was polymorphic among three synonymous SNPs. The effect of nucleotide substitution corresponding to polymorphic SNP P67P on DNase 1L1 activity was examined: the corresponding nucleotide substitution in polymorphic SNP P67P has little effect on the DNase activity. 相似文献
790.