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81.
82.
Suzuki Hitoshi Saito Yoshio Nakada Toshitaka Kaito Chihiro 《Journal of nanoparticle research》2002,4(5):387-394
It was found that smoke particles smaller than 100nm and of different crystal structures can be separated by an electric field. Tungsten oxide smoke curved in the electric field towards the positive electrode plate. The morphology of the particles and dispersion of particles became good in the electric field. By burning of Pb in a mixture gas of Ar (80%) and O2 (20%), red and yellow layer structure particles were simultaneously produced. The flow direction of red and yellow smokes changed by applying an electric field (200V/cm). Red particles flowed towards the negative plate and yellow particles flowed towards the positive plate, i.e. two different structures were separated. Simultaneous growth conditions of SnO and SnO2 were observed and also found that they can be separated by the use of electric field as well as lead oxides. The curve of the smoke is discussed as that the surface net charge was affected by the electric field on the basis of produced particle structure and morphology. 相似文献
83.
Two crystal populations with different melting/reorganization kinetics of isothermally crystallized polyamide 6
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Yoshitomo Furushima Masaru Nakada Kazuhiko Ishikiriyama Akihiko Toda Rene Androsch Evgeny Zhuravlev Christoph Schick 《Journal of Polymer Science.Polymer Physics》2016,54(20):2126-2138
Differential scanning calorimetry and fast scanning chip calorimetry heating experiments were carried out in a wide range of rates of temperature change from 0.2 to 60,000 K s?1 for isothermally crystallized polyamide 6. Multiple melting peaks were observed. With increasing heating rate, the highest‐temperature endotherm shifts toward lower temperatures and finally disappears due to suppression of the reorganization. The critical heating rate to suppress reorganization was 15–50 times higher than the critical cooling rate to cause complete vitrification. On heating at rates higher than the critical heating rate to suppress reorganization, there were observed two melting processes of different kinetics. Four possible assignments were considered regarding the two crystal populations. These are (i) crystals grown during primary and secondary crystallization, (ii) crystals grown in the bulk and nucleated at the surface/substrate, (iii) crystals, which are subjected to different local stress originating from heterogeneities in interlamellar regions, and (iv) the crystal/mesophase polymorphism. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2126–2138 相似文献
84.
The pig liver esterase (PLE)-catalyzed kinetic resolution of half-esters derived from prochiral diesters is described. Generally, the PLE-catalyzed enantioselective hydrolysis of prochiral diesters affords the corresponding half-esters in high yield, because further hydrolysis of the half-esters does not typically occur. However, we found that some half-esters undergo PLE-catalyzed hydrolysis when they are gradually added to a PLE suspension in a potassium phosphate buffer at pH 8.0 via a syringe pump, leading to the kinetic resolution of the half-esters. 相似文献
85.
Mio Koyama Akito Shimomura Katsuhiko Miyamoto Takashige Omatsu 《Applied physics. B, Lasers and optics》2014,116(2):249-254
The frequency-doubling of a picosecond vortex fiber laser, formed of a 1-μm picosecond master laser and a large-mode-area fiber amplifier by using a nonlinear LiB3O5, crystal, was performed. A maximum second-harmonic power of 7.7 W was achieved, corresponding to a conversion efficiency of 31 %. The second harmonic had an annular spatial form owing to a phase singularity with a doubled topological charge, and its wavefront helicity was selectively controlled by tuning the stress applied to the fiber amplifier. 相似文献
86.
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
87.
Takashi Azuma Norihide Nakada Naoyuki Yamashita Hiroaki Tanaka 《International journal of environmental analytical chemistry》2013,93(9):853-862
We optimised the simultaneous analysis of four analytes, namely three anti-influenza drugs (oseltamivir (OS), zanamivir (ZAN) and amantadine (AMN)) and one metabolite of OS (oseltamivir carboxylate (OC)), in sewage treatment plant (STP) influent and effluent by verifying the types and conditions of solid phase extraction (SPE) appropriate for LC-MS/MS analysis. In summary, these target analytes were extracted from aqueous samples (30–50 mL) by using strong cation-exchange SPE cartridges (500 mg adsorbent) under acidic conditions (pH 3–4). After washing of the cartridges with acidified water (pH 3.0, 3 mL) and methanol (3 mL), the analytes were eluted with a mixed solvent (2 mL) of 10% (v/v) triethylamine in a 1:1 (v/v) mixture of acetone and water. Application of this technique to the target compounds should yield a comprehensive understanding of the occurrence and fate of anti-influenza drugs in the water environment. 相似文献
88.
Kazuhiro Tsuna Naoyoshi Noguchi Prof. Dr. Masahisa Nakada 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(17):5476-5486
The enantioselective total synthesis of (+)‐ophiobolin A is described. This total synthesis features the construction of the spiro CD ring of (+)‐ophiobolin A through a stereoselective intramolecular Hosomi–Sakurai cyclization reaction, the joining of the A ring to the CD ring by using a reaction reported by Utimoto, and the construction of the ophiobolin eight‐membered carbocyclic ring through ring‐closing metathesis (RCM), which was performed for the first time in this study. This successful RCM reaction required the use of a substrate that contained either a benzyloxy or a methoxymethoxy group at the C5 position and either an isopropenyl group or its hydroxylated form at the C6 position. 相似文献
89.
90.
Kazutoyo Endo Hiroshi Haruta Chikako Honda Motomi Katada Hiromichi Nakahara Masami Nakada Masakatsu Saeki Yasuyuki Aratono 《Hyperfine Interactions》1994,91(1):645-649
Iron-barium glaze was prepared from commercially available materials for ceramic arts and from chemical reagents, and investigated by means of Mössbauer spectroscopy and an electron probe micro analyzer (EPMA). Mössbauer spectra showed a doublet of paramagnetic high-spin Fe(II) and Fe(III) incorporated into aluminosilicate, and the magnetically-split hyperfine structures of hematite and magnetite, depending on the iron content and firing conditions. The EPMA indicated striped patterns on the secondary electron images, and the fluorescent X-ray analysis proved that the patterns are due to the heterogeneous distribution of elements in the glaze. 相似文献