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71.
研究了三甲基硅烷基丙块与五甲基二硅烷基丙块共聚物〔poly(TMSP-co-PMDSP)〕的成膜特点。poly(TMSP-co-PMDSP)膜的气体透过系数分别为:P_(O2):4×10~3~12×10~3,P_(N2):3×10~3~8×10~3和P_(CO2):2×10~4~4×10~4barrer,气体透过稳定性低,透过行为偏离第二Fick定律,过系数下降,其中溶解系数降低的比例远大于扩散系数的增加比例,在含有凝聚性气体的环境里,膜的气体透过出现表面吸附控制的特征。 相似文献
72.
Deguchi K Keira T Yamada K Ito H Takegawa Y Nakagawa H Nishimura S 《Journal of chromatography. A》2008,1189(1-2):169-174
A novel chromatographic approach coupling anion-exchange (diethylaminoethylene) and hydrophilic-interaction (amide or zwitterionic type) columns was developed for the separating of 2-pyridylamino derivatives of N-glycans (PA-N-glycans). This is a kind of on-line, two-dimensional (2D) separation approach in hydrophilic-interaction chromatography (called the 2D-HILIC method), analogous to that of coupling cation- (or anion-, or mixed ion-) exchange and reversed-phase columns in hydrophobic interaction (reversed-phase) chromatography. The efficiency of the 2D-HILIC method was tested with biantennary neutral and sialylated PA-N-glycan standards by properly combining linear gradient elutions of water-acetonitrile and spiked-salt (ammonium acetate) elutions. The retention time RSDs of all the peaks in three sequential runs of a 100 min cycle are less than 0.52%, which indicates a reasonably good repeatability of the 2D-HILIC method. Then, the method was applied to a complex mixture of PA-N-glycans from human serum proteins. It was demonstrated that the neutral PA-N-glycans and mono-, di-, tri-, and tetrasialylated PA-N-glycans are able to be eluted in turn according to the number of sialic acids in an automated (programmed) single run. 相似文献
73.
74.
T.Nakagawa M.Kidera Y.Higurasi J.Ohnishi T.Kageyama T.Aihara A.Goto Y.Yano 《中国物理 C》2007,31(Z1):133-136
We measured the main plasma parameters(density of electron,temperature of electron and ion confinement time)and beam intensity of various heavy ions as a function of B_(min).The B_(min) strongly affects the field gradient at the resonance zone,consequently the plasma parameters and beam intensity are changed. Based on these experimental results,we started to construct new 18GHz ECRIS and make a detailed design of the 28GHz SC-ECRIS for RIKEN RI beam factory project. 相似文献
75.
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
76.
Tatsuo Nakagawa Satoshi Fukura Munenori Nakai Kazumasa Sugiyama Ryohei Kokawa Hiroyuki Kagi 《Optical Review》2006,13(4):269-275
We constructed a scanning near-field optical microscope (SNOM) on a commercially available atomic force microscopy (AFM) apparatus
(SPM-9500J2; Shimadzu Corp.) to measure the stress distribution in ceramic composite materials. Features of our SNOM system
are: (1) a compact SNOM head substituted for the original AFM head; (2) a wide scanning range (125 × 125 μm2) inherited from the original scanner; (3) use of conventional shear-force regulation; (4) an optical system for the illumination-collection
(I-C) mode; (5) excitation by a 488 nm line of an Ar-ion laser, and (6) light detection by photon counting or a polychromator
equipped with an electronically cooled charge coupled device (CCD). This SNOM system was used to measure the surface structure
and stress distribution of an Al2O3/ZrO2 eutectic composite. We simultaneously measured topographic images and fluorescence spectra of an Al2O3/ZrO2 eutectic composite. We estimated its peak intensity, peak position, and peak width from the fluorescence spectrum during
scanning, which respectively correspond to the abundance of Al2O3, stress in the grain, and the anisotropy of that stress. Mapping images showed that the stress and its anisotropy were weaker
in the center of the Al2O3 grain than its boundary between Al2O3 and ZrO2. That observation suggests that Al2O3 underwent intense anisotropic stress induced by volume expansion in the phase transition of ZrO2 from the cubic phase to the monoclinic phase during preparation. 相似文献
77.
78.
Dr. Hiromi Oshita Takashi Suzuki Kyohei Kawashima Prof. Dr. Hitoshi Abe Prof. Dr. Fumito Tani Prof. Dr. Seiji Mori Prof. Dr. Tatsuo Yajima Prof. Dr. Yuichi Shimazaki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(32):7649-7658
In order to gain new insights into the effect of the π–π stacking interaction of the indole ring with the CuII–phenoxyl radical as seen in the active form of galactose oxidase, we have prepared a CuII complex of a methoxy-substituted salen-type ligand, containing a pendent indole ring on the dinitrogen chelate backbone, and characterized its one-electron-oxidized forms. The X-ray crystal structures of the oxidized CuII complex exhibited the π–π stacking interaction of the indole ring mainly with one of the two phenolate moieties. The phenolate moiety in close contact with the indole moiety showed the characteristic phenoxyl radical structural features, indicating that the indole ring favors the π–π stacking interaction with the phenoxyl radical. The UV/Vis/NIR spectra of the oxidized CuII complex with the pendent indole ring was significantly different from those of the complex without the side-chain indole ring, and the absorption and CD spectra exhibited a solvent dependence, which is in line with the phenoxyl radical–indole stacking interaction in solution. The other physicochemical results and theoretical calculations strongly support that the indole ring, as an electron donor, stabilizes the phenoxyl radical by the π–π stacking interaction. 相似文献
79.
Haruka Takeuchi Prof. Dr. Shinsuke Inuki Kohei Nakagawa Takaaki Kawabe Dr. Atsuhiko Ichimura Prof. Dr. Shinya Oishi Prof. Dr. Hiroaki Ohno 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(47):21396-21401
We report herein a nonbiomimetic strategy for the total synthesis of the plicamine-type alkaloids zephycarinatines C and D. The key feature of the synthesis is a stereoselective reductive radical ipso-cyclization using visible-light-mediated photoredox catalysis. This cyclization enabled the construction of a 6,6-spirocyclic core structure through the addition of a carbon-centered radical onto the aromatic ring. Biological evaluation of zephycarinatines and their derivatives revealed that the synthetic derivative with a keto group displays moderate inhibitory activity against LPS-induced NO production. This approach could offer future opportunities to expand the chemical diversity of plicamine-type alkaloids as well as providing useful intermediates for their syntheses. 相似文献
80.
Ahmed Ashour Yhiya Amen Toshinori Nakagawa Yasuharu Niwa Amira Mira Koichiro Ohnuki 《Natural product research》2020,34(12):1750-1755
AbstractAn aliphatic ester of hydroxysalicylic acid (6), reported for the first time from a natural source in addition to five known compounds were isolated from the fermented Carica papaya L. preparation, a commercialized functional food. The known compounds were identified as 5-hydroxymethylfurfuraldehyde (1), trans-caffeic acid (2), butyl 4-hydroxybenzoate (butylparaben) (3), lycopene (4), benzyl isothiocyanate (5). Compounds 1 and 3 were reported for the first time from Papaya fruits through this study. The new compound showed a moderate antioxidant activity and a potent hair growth stimulating activity in vitro. 相似文献