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41.
Akihiko Kameyama Hideharu Ishida Makoto Kiso Akira Hasegawa 《Journal of carbohydrate chemistry》2013,32(5):799-804
Abstract Sialoglycoconjugates such as glycoproteins and glycolipids are present as components of cell memberanes and play important roles1,2 in biological systems. Sialyl neolactotetrasyl ceramide (IV3NeuAcnLc4Cer), a complex type of ganglioside, was isolated as the major ganglioside of human erythrocytes3 and was shown to be a receptor of that this glycolipid induces granulocytic differentiation of human premyelocytic leukemia cell. 相似文献
42.
Treatment of 2,2,4,4-tetramethyl-1,5-diphenyl-6,7-dithiabicyclo[3.1.1]heptane 6-endo-oxide ( 2 ) with Montmorillonitc K 10 in dichloromethane gave 2,2,-4,4-tetramethyl-1,5-diphenyl-7,8-dithia-6-oxabicyclo-[3.2.1]octane ( 6 ) (11%) with recovery of 2 (87%). Under similar reaction conditions, the 6-exo-oxide 7 and the sulfenate 6 gave a mixture of 6 (21%), 2 (67%), and 7 (9%) and a mixture of 2 (89%) and 6 (9%), respectively. These results indicate the relative thermodynamic stabilities of the three compounds to be 2 > 6 > 7 . PM3 calculations on these compounds showed the heats of formation (kcal/mol) to be in the following order: 6 (44.12783), 2 (57.46721), and 7 (59.37918). The driving force of this unusual 1,2-rearrangement of 2 and 7 to 6 would be the release of the ring strain of the bicyclo[3.1.1]heptane system of 2 and 7 by ring expansion. 相似文献
43.
Atsuya Muranaka Yoshiaki Asano Akihiko Tsuda Atsuhiro Osuka Nagao Kobayashi 《Chemphyschem》2006,7(6):1235-1240
The electronic excited states of a meso-meso beta-beta doubly linked bis-porphyrin are comprehensively investigated by measuring its circular dichroism (CD) and magnetic circular dichroism (MCD) spectra. The observed spectroscopic properties are rationalized by DFT calculations. The frontier molecular orbitals (MOs) are constructed by the linear combinations of the constituent monomers' four MOs. Comparison of a theoretical CD spectrum based on time-dependent DFT (TDDFT) with the experimental spectra resulted in the assignment of the helical conformation of the dimer. This assignment is contrary to the previous assignment based on the point-dipole approximation (exciton coupling theory). 相似文献
44.
Jun Yano Akihiko Muta Yutaka Harima Akira Kitani 《Journal of Solid State Electrochemistry》2011,15(3):601-605
A poly(2,5-dimethoxyaniline) (PDMA) film was coated on the iron surface by the electropolymerization of 2,5-dimethoxyaniline in neutral buffer solution (pH?6.86). The PDMA film strongly adhered to the surface because of the polar methoxy groups of the PDMA molecules. The fact that no electrochemical response of the PDMA film-coated iron electrode to dissolved Fe2+ exhibited that the PDMA film was less permeable to dissolved species, acting as a diffusion barrier against agents causing corrosion such as H2O and O2. The PDMA film coating greatly lowered the anodic current peak ascribed to the anodic dissolution of iron and the corrosion current in strongly acidic medium, 0.5?M H2SO4 aqueous solution (1?M?????mol?dm??) as well as neutral medium (pH?6.86). The high anti-corrosion ability was due to a hybrid effect of the PDMA film not only as the diffusion barrier, but also as an in situ oxidant in spite of the slight redox activity of PDMA. In addition, the PDMA film is much more durable and adhesive than polyaniline film against over-oxidation. 相似文献
45.
Akihiko Yukie 《Mathematische Annalen》1992,292(1):355-374
Partially supported by NSF Grant DMS-8803085, DMS-8610730 相似文献
46.
Akihiko Ohtsu 《Optics Communications》2010,283(20):3831-3837
The author investigated second-harmonic (SH) wave patterns generated by focused vortex beams with radial and azimuthal polarizations. Expressions for electric field components near the focus through a dielectric interface were obtained based on vector diffraction theory. Furthermore, the (110) and (001) planes of a crystal classified in the symmetry group 4?3m were considered as second order nonlinear optical medium to analyze nonlinear polarization and the intensity distributions of the SH wave in the far-field were simulated for topological charge m = 1 and 2. Numerical simulations indicated that the intensity and emission pattern of the SH wave depended principally on the electric field component and distribution near the focus. In particular, for the (001) plane, the intensity of the SH wave was strongly correlated with the existence of a longitudinal electric field. 相似文献
47.
The generation and recognition of a record-length 511-chip optical code is experimentally demonstrated by use of a superstructured fiber Bragg grating (SSFBG) with a chip rate of 640 Gchips/s. Very high reflectivity (92%) is achieved with high-quality correlation properties. The temperature deviation tolerance is approximately +/- 0.3 degrees C, which is within the package's temperature stability range (+/- 0.1 degrees C). Experimental results show good agreement with the theory. They indicate the SSFBG's potential for processing a long optical code with an ultrahigh chip rate, which could significantly improve the system's performance. 相似文献
48.
Temperature sensitivity of Ge-B-SiO(2) waveguide Bragg gratings on a crystallized glass substrate 总被引:1,自引:0,他引:1
Waveguide Bragg gratings were fabricated by plasma-enhanced chemical-vapor deposition followed by irradiation with KrF excimer laser light through a phase mask. The period of the Bragg grating was 0.53 mum, and the Bragg wavelength was ~1.53 mum . The temperature dependence of the Bragg wavelength was 11 pm/ degrees C for a 10GeO(2) -90SiO(2)(mol.%) core waveguide on a Si substrate, and the Bragg wavelength shift was successfully reduced to 5.0pm/ degrees C by use of a 14GeO(2)-12B(2)O(3)-74SiO(2) (mol.%) core and a crystallized glass substrate with a thermal-expansion coefficient of -2.0x10(-6)(/ degrees C) . 相似文献
49.
Mohsen Pourahmadi Akihiko Inoue Yukio Kasahara 《Proceedings of the American Mathematical Society》2007,135(4):1233-1239
For a nonnegative integrable weight function on the unit circle , we provide an expression for , in terms of the series coefficients of the outer function of , for the weighted distance , where is the normalized Lebesgue measure and ranges over trigonometric polynomials with frequencies in , , . The problem is open for .
50.
Hideo Inaba Fujio Komatsu Akihiko Horibe Naoto Haruki Akito Machida 《Heat and Mass Transfer》2008,44(11):1305-1313
This paper describes heat and mass transfer characteristics of organic sorbent coated on heat transfer surface of a fin-tube
heat exchanger. The experiments in which the moist air was passed into the heat exchanger coated with sorption material were
conducted under various conditions of air flow rate (0.5–1.0 m/s) and the temperature of brine (14–20°C) that was the heat
transfer fluid to cool the air flow in the dehumidifying process. It is found that the sorption rate of vapor is affected
by the air flow rate and the brine temperature. Meanwhile, the attempt of clarifying the sorption mechanism is also conducted.
Finally the average mass transfer coefficient of the organic sorbent coated on heat transfer surface of a fin-tube heat exchanger
is non-dimensionalzed as a function of Reynolds number and non-dimensional temperature, and it is found that the effect of
non-dimensional temperature on them is larger than Reynolds number . 相似文献