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91.
T. Sumikama M. Ogura Y. Nakashima T. Iwakoshi M. Mihara M. Fukuda K. Matsuta T. Minamisono H. Akai 《Hyperfine Interactions》2004,158(1-4):413-416
We observed the electric quadrupole interaction of 12B implanted in the interstitial site of TiO2 using β-NMR method. The electric field gradients including the direction of the principal axes were determined. The direction agreed
well with the theoretical calculation. 相似文献
92.
Kando M Fukuda Y Pirozhkov AS Ma J Daito I Chen LM Esirkepov TZh Ogura K Homma T Hayashi Y Kotaki H Sagisaka A Mori M Koga JK Daido H Bulanov SV Kimura T Kato Y Tajima T 《Physical review letters》2007,99(13):135001
In a plasma wake wave generated by a high power laser, modulations of the electron density take the shape of paraboloidal dense shells, moving almost at the speed of light. A counterpropagating laser pulse is partially reflected from the shells, acting as relativistic flying mirrors, producing a time-compressed frequency-multiplied pulse due to the double Doppler effect. The counterpropagating laser pulse reflection from the plasma wake wave accompanied by its frequency multiplication (with a factor from 50 to 114) was detected in our experiment. 相似文献
93.
We applied a time-resolved small-angle neutron scattering technique to the vesicle system of dimyristoylphosphatidylcholine for the first time to determine lipid kinetics. The observed kinetics could be explicitly represented by a simple model that includes two independent kinetic parameters, i.e., the rates of transbilayer and interbilayer exchange. This technique is perfectly suited for the determination of lipid exchange kinetics in equilibrium and applicable to evaluation of the activity of the factors relevant to lipid migration, such as translocase and lipid transfer proteins. 相似文献
94.
95.
meso‐Dibenzoporphycene has a Large Bathochromic Shift and a Porphycene Framework with an Unusual cis Tautomeric Form
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Dr. Koji Oohora Ayumu Ogawa Tamaki Fukuda Dr. Akira Onoda Prof. Dr. Jun‐ya Hasegawa Prof. Dr. Takashi Hayashi 《Angewandte Chemie (International ed. in English)》2015,54(21):6227-6230
meso‐Monobenzoporphycene (mMBPc) and meso‐dibenzoporphycene (mDBPc), in which one or two benzene moieties are fused at ethylene‐bridged positions (meso‐positions) of porphycene, were prepared in an effort to further delocalize the π‐electrons within the porphycene molecule. mMBPc and mDBPc were fully characterized by mass spectrometry, 1H and 13C NMR spectroscopy, and X‐ray crystallography. The longest‐wavelength Q‐bands of mMBPc and mDBPc are red‐shifted by 92 nm and 418 nm, respectively, compared to that of the unsubstituted porphycene (Pc). Electrochemical measurements indicate that the HOMO is destabilized and the LUMO is stabilized by the fused benzene moieties at the meso positions. Furthermore, both XPS and theoretical studies support the presence of a cis tautomeric form in the ground state of mDBPc, despite the fact that essentially all known porphycene derivatives adopt the trans tautomeric form. 相似文献
96.
97.
The transient heat transfer behavior in the case of heat removal from a cylindrical heat storage vessel packed with spherical particles was investigated experimentally for various factors (flow rate, diameter of spherical particles packed, temperature difference between flowing cold air and spherical particles accumulating heat, and physical properties of spherical particles). The experiments were covered in ranges of Reynolds number based on the mean diameter of spherical particles packed Red = 10.3–2200, porosity?=0.310 to 0.475, ratio of spherical particle diameter to cylinder diameterd/D = 0.0075–0.177 and ratio of length of the cylinder to cylinder diameterL/D=2.5–10. It was found that especially the flow rate and the dimension of spherical particles played an important role in estimating the transient local heat transfer characteristics near the wall of the cylindrical vessel in the present heat storage system. As flow rate and diameter of spherical particles were increased under a given diameter of the cylinder heat storage vessel, the mean heat transfer coefficient between the flow cold air and the hot spherical particles increased and the time period to finish removing heat from the vessel reduced. In addition, the useful experimental correlation equations of mean heat transfer coefficient between both phases and the time period to finish removing heat from the vessel were derived with the functional relationship of Nusselt numberNu d=f [modified Prandtl numberPr * (d/D), Red) and Fourier numberFo = f(d/D, L/D, Pr*, Red). 相似文献
98.
Kuniaki Tatsuta Sonoko TokishitaTomohiro Fukuda Takaaki KanoTadaaki Komiya Seijiro Hosokawa 《Tetrahedron letters》2011,52(9):983-986
K1115 B1, isolated from the broth of Streptomyces species, was found to be a mixture of stereoisomers. Authors synthesized all stereoisomers of K1115 B1 by convergent synthesis coupling a rhamnose derivative, an isobenzofuranone, and a chiral tetraol. Comparison of 1H NMR spectra and optical rotations made it clear that the absolute structures of K1115 B1α (the major isomer) and K1115 B1β (the minor isomer) were (1R, 17S)- and (1R, 17R)-configurations, respectively. The optical rotations of the stereoisomers revealed that alnumycin, reported as the identical structure with K1115 B1, might be another mixture of stereoisomers. 相似文献
99.
Interactions between proteins and biomaterial surfaces correlate with many important phenomena in biological systems. Such interactions have been used to develop various artificial biomaterials and applications, in which regulation of non-specific protein adsorption has been achieved with bioinert properties. In this research, we investigated the protein adsorption behavior of polymer brushes of dendrimer self-assembled monolayers (SAMs) with other generations. The surface adsorption properties of proteins with different pI values were examined on gold substrates modified with poly(amidoamine) dendrimer SAMs. The amount of fibrinogen adsorption was greater than that of lysozyme, potentially because of the surface electric charge. However, as the generations increased, protein adsorption decreased regardless of the surface charge, suggesting that protein adsorption was also affected by density of terminal group. 相似文献
100.
Modification with gold black considerably increased the detection current of protruding micropillar electrodes in microfluidic electrochemical enzyme-linked immunosorbent assay (ELISA). 相似文献