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71.
72.
Fluid flow in a rotating cylindrical container of radius Rw and height H with a co-axially rotating disk of radius Rd at the fluid surface is numerically investigated. The container and the disk rotate with angular velocities Ωw and Ωd, respectively. We solve the axisymmetric Navier-Stokes equations using a finite-volume method. The effects of the relative directions and magnitudes of the disk and container rotations are studied. The calculations are carried out with various ratios of Ωw and Ωd for H/Rw = 2 and Rd/Rw = 0.7. Streamlines and velocity vectors in the meridional plane and azimuthal velocities are obtained. The flow fields in the meridional plane are discussed with relation to azimuthal velocities in the interior of the container. The numerical results are also compared with experimental data. 相似文献
73.
Ogino M Nakada Y Negoro N Itokawa S Nishimura S Sanada T Satomi T Kita S Kubo K Marui S 《Chemical & pharmaceutical bulletin》2011,59(11):1369-1375
As a part of our research for novel potent and orally available acyl-CoA: cholesterol acyltransferase (ACAT) inhibitors that can be used as anti-atherosclerotic agents, we recently reported the discovery of the (4-phenylcoumarine)acetanilide derivative 1. However, compound 1 showed adrenal toxicity in animal models. In order to search for safer ACAT inhibitors that do not have adrenal toxicity, we examined the inhibitory activity of ACAT in human macrophage and adrenal cells. The introduction of a carboxylic acid moiety on the pendant phenyl ring and the adjustment of the lipophilicity led to the discovery of (2E)-3-[7-chloro-3-[2-[[4-fluoro-2-(trifluoromethyl)phenyl]amino]-2-oxoethyl]-6-methyl-2-oxo-2H-chromen-4-yl]phenyl]acrylic acid (21e), which showed potent ACAT inhibitory activity in macrophages and a selectivity of around 30-fold over adrenal cells. In addition, compound 21e showed high adrenal safety in guinea pigs. 相似文献
74.
A. Yoshikawa H. Ogino J. B. Shim M. Nikl N. Solovieva T. Fukuda 《Radiation measurements》2004,38(4-6):467-470
Rod-shaped (Lu1−xYbx)3Al5O12 with x=0.05, 0.15, 0.30 and (Y1−xYbx)AlO3 with x=0.05, 0.10, 0.30 single crystals were grown by the micro-pulling-down method. Edge-defined film-fed growth method was used to prepare (Y0.9Yb0.1)VO4 crystal, while Ca8(La1.98Yb0.02)(PO4)6O2 crystal was grown by the Czochralski method. Luminescence of these crystals was studied with main attention paid to the charge transfer emission of Yb3+. Temperature tuned decay times in the time scale of units—tens of nanosecond was measured as a feature possibly interesting for an application in scintillation detectors in positron emission tomography. 相似文献
75.
We study Nekrasov's deformed partition function $Z(\varepsilon_1,\varepsilon_2,\vec{a};\mathfrak q,\boldsymbol\beta)$ of 5-dimensional
supersymmetric
Yang-Mills theory compactified on a circle. Mathematically it is the
generating function of the characters of the coordinate rings of the moduli
spaces of instantons on $\mathbb R^4$. We show that it satisfies a system of
functional equations, called blowup equations, whose solution is unique.
As applications, we prove (a) $F(\varepsilon_1,\varepsilon_2,\vec{a};\mathfrak q,\boldsymbol\beta) = \varepsilon_1\varepsilon_2
\log Z(\varepsilon_1,\varepsilon_2,\vec{a};\mathfrak q,\boldsymbol\beta)$ is regular at $\varepsilon_1 = \varepsilon_2 = 0$
(a part of Nekrasov's conjecture), and (b) the genus $1$ parts, which are first several Taylor coefficients of $F(\varepsilon_1,\varepsilon_2,\vec{a};\mathfrak
q,\boldsymbol\beta)$, are written explicitly in terms of $\tau = d^2 F(0,0,\vec{a};\mathfrak q,\boldsymbol\beta)/da^2$ in
rank $2$ case. 相似文献
76.
77.
Elastic and inelastic scattering of vector polarized deuterons from even samarium isotopes at 56 MeV
K. Hatanaka N. Matsuoka T. Saito K. Hosono M. Kondo S. Kato T. Higo S. Matsuki K. Ogino 《Nuclear Physics A》1983,403(1):109-133
Differential cross sections and vector analyzing powers of deuteron elastic and inelastic scattering have been measured at 56 MeV over the whole range of the even samarium isotopes. Comprehensive analyses were performed with the optical model and the coupled-channels formalism. In the optical model analysis, calculations with a global parameter set could reproduce the experimental data only for the vibrational nuclei. The strong coupling approximation was applied assuming the 144, 148, 150Sm to be harmonic vibrators and the 152,154Sm symmetric rotators. The 2λ (λ = 2, 3, 4, 6) pole deformation parameters were deduced from a systematic coupled-channels analysis. The transition strengths were extracted from the deformed optical potentials and compared with the corresponding electromagnetic ones. The transition rates for the rotational nuclei agreed with the electro-magnetic ones, but those for the vibrational nuclei gave the systematically smaller values. The latter fact was attributed to the difference between the proton and neutron transition matrix elements near the neutron-closed-shell nuclei. The ratios of the two matrix elements were obtained. 相似文献
78.
Spectrophotometric and thermodynamic investigations are reported of the interactions between anionic surfactant (sodium dodecyl sulfate) and six azo oil dyes (benzene azo naphthalene type) which have an amino group at 4-position of naphthalene. A pronounced spectral change in the dye solution occurs on addition of surfactant. For increasingly surfactant concentrations (below the CMC), the interaction between dye and surfactant is so sharp that the systems may be said to exhibit an isosbestic point; then a new absorption band appears at longer wavelengths. The spectral data can be quantitatively interpreted in terms of a complex formation. The equilibrium coefficients of the complex formation are determined at different temperatures. The thermodynamic parameters of the complex formations (the free energy change (G), enthalpy change (H) and change in entropy (S) are also calculated. The reaction of complex formation is exothermic (H negative).G is dependent on the hydrophobic nature andpKa of the dye. These complexes will form due to hydrophilic-hydrophilic interaction and will become more stable due to hydrophobic-hydrophobic interaction.With increasing amounts of complex, the infinite adsorption, the exhaustion and the rate constant of dyeing for nylon decrease. 相似文献
79.
K. Prabhakaran K. V. P. M. Shafi Y. Yamauchi K. Tsubaki A. Ulman Y. Homma T. Ogino 《Applied Surface Science》2002,190(1-4):161-165
Here, we demonstrate a “plug and play” approach to achieve multi-functionalization of Si. In this approach, externally synthesized functional nanoparticles are introduced onto device quality Si wafers and the surface chemical bonds are manipulated. Sonochemically synthesized Fe2O3 nanoparticles are introduced onto Si from an alcohol suspension. On annealing this sample in ultra-high vacuum, the oxygen atoms change the bonding partner from Fe to Si and desorb as SiO at 750 °C. This results in the formation of nanoparticles of Fe on the surface and exhibits ferromagnetic behavior. Deposition of a thin layer (2 nm) of Si onto the sample containing the metallic Fe nanoparticles followed by annealing at 560 °C leads to optically active Si. Photoluminescence measurements show that this sample emits light at three different wavelengths, namely 1.57, 1.61 and 1.63 μm, when excited by He–Ne or Ar lasers. Oxidation of this material results in the formation of a selective capping layer of SiO2. Thus we obtain multi-functional Si in an “all in one” form and we believe that this approach is universal. 相似文献
80.
A total of 16 alkaloids, exemplified by mersinine A and its congeners, and constituting a new subclass of the monoterpenoid indoles, were isolated exclusively and for the first time from Kopsia singapurensis. The structures of these alkaloids were established by spectroscopic methods and in some instances confirmed by X-ray diffraction analysis. A possible biogenetic route from an aspidofractinine precursor is proposed. Compounds 1, 2, 3, 9, and 10 were found to reverse multidrug-resistance in drug-resistant KB cells. 相似文献