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71.
Yoko Hirohara Yoshitaka OKawa Toshifumi Mihashi Tatsuo Yamaguchi Naoki Nakazawa Yasuko Tsuruga Hiroyuki Aoki Naoyuki Maeda Ichiro Uchida Takashi Fujikado 《Optical Review》2007,14(3):151-158
The purpose of this paper was to investigate the feasibility of a newly developed hyperspectral fundus imaging camera with
a liquid crystal tunable filter. The intensities of different wavelengths of light transmitted through an artery, vein, and
the area surrounding these vessels and reflected out were measured, and the differential spectral absorptions were analyzed.
Measurements were made from 16 normal eyes and from two artificial capillaries. The ratios of absorption (ROA) of arteries
to veins from 500 to 580 nm (range 1) and from 600 to 720 nm (range 2) were calculated. For all eyes, the ROArange1 was larger than ROArange2. The ROA obtained from the artificial capillary filled with blood saturated with oxygen or nitrogen was similar to that of
simulated data of oxy- and deoxyhemoglobin extinction rate. Most ROAs of human eyes were lower than those of the simulated
data and the artificial capillaries. Oxygen saturation analysis by hyperspectral fundus imaging of retinal vessels were qualitatively
in agreement with thein vitro analysis or simulated values. However, further improvements are necessary to evaluate the oxygen saturation quantitatively
in the retinal blood vessels. 相似文献
72.
Ignition enhancement by addition of NO and NO2 from a N2/O2 plasma torch in a supersonic flow 总被引:1,自引:0,他引:1
Kenichi Takita Naoyuki Abe Goro Masuya Yiguang Ju 《Proceedings of the Combustion Institute》2007,31(2):2489-2496
The effects of NO and NO2 produced by using a plasma jet (PJ) of a N2/O2 mixture on ignition of hydrogen, methane, and ethylene in a supersonic airflow were experimentally and numerically investigated. Numerical analysis of ignition delay time showed that the addition of a small amount of NO or NO2 drastically reduced ignition delay times of hydrogen and hydrocarbon fuels at a relatively low initial temperature. In particular, NO and NO2 were more effective than O radicals for ignition of a CH4/air mixture at 1200 K or lower. These ignition enhancement effects were examined by including the low temperature chemistry. Ignition tests by a N2/O2 PJ in a supersonic flow (M = 1.7) for using hydrogen, methane, and ethylene injected downstream of the PJ were conducted. The results showed that the ignitability of the N2/O2 PJ is affected by the composition of the feedstock and that pure O2 is not the optimum condition for downstream fuel injection. This result of ignition tests with downstream fuel injection demonstrated a significant difference in ignition characteristics of the PJ from the ignition tests with upstream fuel injection. 相似文献
73.
The first example of enantioselective intermolecular cycloaddition of carbonyl ylides with indoles is described. The cycloaddition of five- and six-membered carbonyl ylides derived from diazodiketoesters with N-methylindoles under catalysis by dirhodium(II) tetrakis[N-tetrachlorophthaloyl-(S)-tert-leucinate], Rh(2)(S-TCPTTL)(4), gave cycloadducts in high yields and with high levels of enantioselectivity (up to 99% ee) as well as excellent exo diastereoselectivity. 相似文献
74.
75.
Yusuke Himei Tomohiro Nagakane Naoyuki Kitamura Akihiko Sakamoto 《Journal of Non》2008,354(27):3113-3119
Reduction in the temperature coefficient of the optical path length, dS/dT of Li2O-Al2O3-SiO2 glass-ceramics with near-zero thermal expansion coefficient was attempted using control of the temperature coefficient of electronic polarizability, ?, and the thermal expansion coefficient, α. The dS/dT value of 2.6 mol% B2O3-doped glass-ceramic was 12.5 × 10−6/°C, which was 0.9 × 10−6/°C smaller than that of B2O3-free glass-ceramic. On the other hand, reduction in dS/dT through B2O3 doping was not confirmed in precursor glasses. Results showed that reduction in dS/dT of the glass-ceramic through B2O3 doping is caused by the reduction in ?. The reduction in ? from B2O3 doping was probably attributable to numerical reduction in non-bridging oxide ions with larger ? value by the concentration of boron ions in the residual glass phase. In addition, application of hydrostatic pressure during crystallization was effective to inhibit precipitation of β-spodumene solid solution, which thereby decreases dS/dT. The dS/dT value of B2O3-doped glass-ceramic crystallized under 196 MPa was 11.7 × 10−6/°C. That value was slightly larger than that of silica glass. The α value of this glass-ceramic was smaller than that of silica glass. 相似文献
76.
With an equiaffine immersion of codimension 1 into the affine space with the natural equiaffine structure, the conormal map is associated. In this paper, for an equiaffine immersion of general codimension into the space, we shall define the map corresponding to the conormal map, which is called the transversal volume element map. And we shall investigate if, an equiaffine immersion of general codimension into the space is determined by its affine fundamental form and its transversal volume element map. 相似文献
77.
The sequential Sonogashira reaction and the cyclization reaction of various 2-iodoanilines and terminal alkynes in the presence of a palladium catalyst and tetrabutylammonium fluoride (TBAF) gave the corresponding 2-substituted indoles in good yields. 相似文献
78.
Naoyuki Koike 《Results in Mathematics》2003,43(1-2):150-155
A non-degenerate equiaffine immersion of codimension one into an equiaffine space is locally expressed in terms of its conormal map and its affine fundamental form. The expression is called the Lelieuvre’s formula. We recently defined the notions of an equiaffine immersion of general codimension and its transversal volume element map. In this paper, we locally express a non-degenerate equiaffine immersion of general codimension into an equiaffine space in terms of its transversal volume element map and its affine fundamental form. 相似文献
79.
Yoko Hirohara Toshifumi Mihashi Asaki Suzaki Teruhito Kuroda Jennifer Elise Kelly Naoyuki Maeda Takashi Fujikado 《Optical Review》2006,13(5):396-404
To assess optical characteristics of bifocal soft contact lenses (BCLs) in use, we measured wavefront aberrations of human
eyes, of eyes with a monofocal soft contact lens (MCL), and of eyes with a BCL. Modulation transfer functions (MTFs), Strehl
ratios, and simulated images for far and near vision were produced with the measured aberrations. High order aberrations of
subject 1 were significantly smaller than those of subject 2 (t-test, P = 0.001). We found that wearing the BCL improved the optical quality of an eye in subject 1, expressed as the horizontal
MTF from 2 to 48 cycles per degree (cpd) for near vision and the Strehl ratio (t-test, P = 0.009 for Strehl ratio). But we did not find the same effect in subject 2. This difference may be due to the difference
in the aberrations of the eyes of the two subjects. 相似文献
80.
Naoyuki Takahashi Arei Niwa Takato Nakamura 《Journal of Physics and Chemistry of Solids》2004,65(7):1259-1263
Indium nitride prepared under atmospheric pressure using a halide chemical vapor deposition method has been examined by means of a variety of analytical techniques. Scanning electron microscopic observations showed that the crystals deposited onto a Si(100) substrate have hexagonal pillar structure. Based on the X-ray diffraction and X-ray pole-figure analyses, it was deduced that each InN pillar crystal grows with a different rotation angle around the 〈001〉 axis. Transmission electron diffraction showed that they are of single-like form. This was also confirmed by the selected area electron diffraction image as well. 相似文献