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51.
We consider a diffuse interface model for the flow of two viscous incompressible Newtonian fluids with different densities in a bounded domain in two and three space dimensions and prove existence of weak solutions for it. In contrast to earlier contributions, we study a model with a singular nonlocal free energy, which controls the Hα/2-norm of the volume fraction. We show existence of weak solutions for large times with the aid of an implicit time discretization. 相似文献
52.
A Cell‐Targeted Non‐Cytotoxic Fluorescent Nanogel Thermometer Created with an Imidazolium‐Containing Cationic Radical Initiator
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Dr. Seiichi Uchiyama Dr. Toshikazu Tsuji Kyoko Kawamoto Dr. Kentaro Okano Eiko Fukatsu Takahiro Noro Kumiko Ikado Sayuri Yamada Yuka Shibata Dr. Teruyuki Hayashi Dr. Noriko Inada Dr. Masaru Kato Dr. Hideki Koizumi Prof. Hidetoshi Tokuyama 《Angewandte Chemie (International ed. in English)》2018,57(19):5413-5417
A cationic fluorescent nanogel thermometer based on thermo‐responsive N‐isopropylacrylamide and environment‐sensitive benzothiadiazole was developed with a new azo compound bearing imidazolium rings as the first cationic radical initiator. This cationic fluorescent nanogel thermometer showed an excellent ability to enter live mammalian cells in a short incubation period (10 min), a high sensitivity to temperature variations in live cells (temperature resolution of 0.02–0.84 °C in the range 20–40 °C), and remarkable non‐cytotoxicity, which permitted ordinary cell proliferation and even differentiation of primary cultured cells. 相似文献
53.
A water-soluble phospholipid polymer having an active ester group in the side chain, poly[2-methacryloyloxyethyl phosphorylcholine (MPC)-co-n-butyl methacrylate (BMA)-co-p-nitrophenyloxycarbonyl polyethyleneglycol methacrylate (MEONP)(PMBN), was used for the immobilization of an enzyme on a plastic microchip. The MPC polymers with BMA units were adsorbed onto the poly(methyl methacrylate)(PMMA) microchip, and the active ester group in the MEONP unit reacted with the amino groups of the proteolytic enzyme, trypsin. Trypsin was immobilized on the sample reservoir, and catalyzed the hydrolysis of the fluorescently labeled ArgOEt to Arg. The consequent separation of product from the substrate, and their detection, were integrated on the microchip and this meant that all procedures from the enzymatic activity to product detection were completed in less than three minutes. 相似文献
54.
Yasuo Takeuchi Kumiko AzumaMiyo Oshige Hitoshi AbeHiromi Nishioka Kenji SasakiTakashi Harayama 《Tetrahedron》2003,59(10):1639-1646
The stereo-structure of piperidine lactone (3), a synthetic intermediate of the antimalarial agent febrifugine ((+)-1) with a piperidine ring in the trans relative configuration, was re-revised to the cis-form. We determined that isomerization to the trans-form from the cis-form occurred in the stage (6 from 5) of deprotection in Baker's synthesis. 相似文献
55.
In search of biologically active modified steroids, novel 16-oxa-D-homoestrone and -D-homoestradiol 3-methyl ethers were synthesized from 16-oxa-3-methoxy- D -homoestra-1,3,5(10),8,14-pentaen-17a-one. The straightforward synthesis involved stereoselective two-step reduction of the 8,14-diene system. The B/C stereoisomers were also derived from the estrapentaene. The stereostructures of these heterocyclic estrogens were determined on the basis of their spectral data. 相似文献
56.
Kadota I Takamura H Sato K Ohno A Matsuda K Satake M Yamamoto Y 《Journal of the American Chemical Society》2003,125(39):11893-11899
The convergent total syntheses of gambierol (1) and 16-epi-gambierol (2) have been achieved. The ABC and FGH ring segments 4 and 5 were prepared from known compounds 6 and 13, respectively, by linear manners. The fragments prepared were connected by our own synthetic strategy including the intramolecular allylation of alpha-acetoxy ether followed by ring-closing metathesis to furnish the octacyclic ether 3. The diiodoalkene 45, prepared from 3, was converted to the Z-iodoalkene 50 via a novel and stereoselective hydrogenolysis followed by deprotection. Construction of the triene side chain was performed by the modified Stille coupling of 50 with the Z-vinylic stannane 41 to afford 1. The similar transformations were carried out on the epimeric octacycle 34 to give 2, which showed no toxicity against mice at the concentration of 14 mg/kg. 相似文献
57.
58.
Effects of initial water content on steam reforming of aliphatic hydrocarbons with nonthermal plasma
The effects of initial water content on steam reforming of aliphatic hydrocarbons such as methane, propane, and neopentane with nonthermal plasma were analyzed in terms of substrate conversion, carbon recovery, and product selectivity. It was found that water addition increased CO2 yield despite a decrease in substrate conversion. The number of carbon atoms in the substrate hydrocarbon affected the additive effect due to the insufficient supply of oxygen atoms from water. Plausible reaction pathways for the conversion of substrate to COx are proposed to explain the relative concentrations of COx species; these pathways involved different precursors for CO and CO2. 相似文献
59.
Akiko Hori Yasuhide Ishida Takahiro Kikuchi Kumiko Miyamoto Hiroshi Sakaguchi 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(12):o593-o597
In the crystal structure of 6‐phenyl‐3‐thioxo‐2,3,4,5‐tetrahydro‐1,2,4‐triazin‐5‐one, C9H7N3OS, (I), the 1,2,4‐triazine moieties are connected by face‐to‐face contacts through two kinds of double hydrogen bonds (N—H...O and N—H...S), which form planar ribbons along the a axis. The ribbons are crosslinked through C—H...π interactions between the phenyl rings. The molecular structures of two regioisomeric compounds, namely 6‐phenyl‐2,3‐dihydro‐7H‐1,3‐thiazolo[3,2‐b][1,2,4]triazin‐7‐one, C11H9N3OS, (II), and 3‐phenyl‐6,7‐dihydro‐4H‐1,3‐thiazolo[2,3‐c][1,2,4]triazin‐4‐one, C11H9N3OS, (III), which were prepared by the condensation reaction of (I) with 1,2‐dibromoethane, have been characterized by X‐ray crystallography and spectroscopic studies. The crystal structures of (II) and (III) both show two crystallographically independent molecules. While the two compounds are isomers, the unit‐cell parameters and crystal packing are quite different and (II) has a chiral crystal structure. 相似文献
60.
The in vitro reactivities of astaxanthin and β-carotene toward peroxynitrite were investigated and the reaction products after scavenging with peroxynitrite were analyzed. A series of carotenoids substituted with nitro group, 14′-s-cis-15′-nitroastaxanthin, 10′-s-cis-11′-cis-11′-nitroastaxanthin, 14′-s-cis-15′-nitro-β-carotene and 10′-s-cis-11′-cis-11′-nitro-β-carotene, were isolated from the reaction products of carotenoids with peroxynitrite. Carotenoids with nitro derivatives were reported for the first time. These results indicated that astaxanthin and β-carotene could catch peroxynitrite or nitrogen dioxide radical (NO2) in their molecule to form nitrocarotenoids. 相似文献