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61.
4-Hydroxypyrazoles were synthesized by the alkaline hydrolysis of the Baeyer-Villiger oxidation products of 4-formylpyrazoles. This new synthesis of 4-hydroxypyrazoles was applied to the divergent synthesis of withasomnine alkaloids in a unique strategy, for which the key steps included the regioselective Claisen rearrangement of their 4-O-allyl-4-hydroxy-1H-pyrazoles and a Suzuki coupling of 4-trifluoromethanesulfonyloxy-1H-pyrazoles and arylboronic acids. 相似文献
62.
Tomoko Fujino 《Tetrahedron letters》2009,50(28):4101-1156
A convergent route for the solution-phase synthesis of oligomeric triazole-linked analogues of DNA (TLDNA) has been developed. A one-pot procedure for desilylation of masked acetylene and the ensuing copper-catalyzed Huisgen coupling reaction between oligomers allowed the solution-phase synthesis of 7-mer and 8-mer TLDNA in good yield. 相似文献
63.
The effect of phenobarbital (PB) or amitriptyline (AMT) on phospholipid metabolism was studied in rat liver. Administration of PB or AMT caused a marked increase in the microsomal phosphatidylcholine (PC) content. In this context, the activities of glycerophosphate acyltransferase (GAT), phosphatidate cytidylyltransferase (PCT), phosphatidate phosphohydrolase (PPH) and choline phosphotransferase (CPT) in the liver were all increased by PB. In contrast, the activities of GAT and PCT were little affected by AMT, while those of PPH and CPT were significantly increased by AMT. These findings suggest that AMT or PB would increase hepatic microsomal PC synthesis through inducing PPH and then CPT. 相似文献
64.
M. Fujino Y. Kanazawa H. Mikawa S. Kusabayashi M. Yokoyama 《Solid State Communications》1984,49(6):575-577
The critical temperature To in Gill's empirical equation for the charge carrier transport was found to have aclose connection with the glass transition temperature Tg for poly-N-vinylcarbazole containing model compound systems. Interpretations of T0 and μ0, i.e., the drift mobility at T0, were presented. 相似文献
65.
Using coaxial impact collision ion scattering spectroscopy, we have investigated Sn thin film growth on Si(1 1 1)√3×√3-Sn and hydrogen-terminated Si(1 1 1) surfaces at room temperature. Sn formed crystalline film with β-Sn structure on Si(1 1 1)√3×√3-Sn surface, but on the hydrogen-terminated Si(1 1 1) surface, the epitaxial growth of Sn thin film was disrupted, and Sn grew as a polycrystalline film. The growth orientational relationship of the Sn film grown on Si(1 1 1)√3×√3-Sn surface was found to be . In the works, we found that interface structure plays a decisive role for the growth mode, crystallinity, and growth orientation of the growth of thin film. 相似文献
66.
Brandenburg G Cinabro D Liu T Saulnier M Wilson R Yamamoto H Bergfeld T Eisenstein BI Ernst J Gladding GE Gollin GD Palmer M Selen M Thaler JJ Edwards KW McLean KW Ogg M Bellerive A Britton DI Hyatt ER Janicek R MacFarlane DB Patel PM Spaan B Sadoff AJ Ammar R Baringer P Bean A Besson D Coppage D Copty N Davis R Hancock N Kotov S Kravchenko I Kwak N Kubota Y Lattery M Momayezi M Nelson JK Patton S Poling R Savinov V Schrenk S Wang R Alam MS Kim IJ Ling Z Mahmood AH O'Neill JJ Severini H Sun CR 《Physical review letters》1995,75(21):3804-3808
67.
Bergfeld T Eisenstein BI Ernst J Gladding GE Gollin GD Johnson E Karliner I Palmer M Selen M Thaler JJ Edwards KW Bellerive A Britton DI Janicek R MacFarlane DB McLean KW Patel PM Sadoff AJ Ammar R Baringer P Bean A Besson D Coppage D Darling C Davis R Hancock N Kotov S Kravchenko I Kwak N Anderson S Kubota Y Lattery M O'Neill JJ Patton S Poling R Riehle T Smith A Savinov V Alam MS Athar SB Ling Z Mahmood AH Severini H Timm S Wappler F Anastassov A Blinov S Duboscq JE Fulton R Fujino D Gan KK 《Physical review letters》1996,77(22):4503-4507
68.
A method is described for the accurate and precise determination of alumina and silica in bauxites with the aid of a 227Ac-Be isotopic neutron source with a total neutron output of 108 n s-1. Three ores can be analysed in triplicate within 4 h, including the determination of the natural radioactivity of the ores. Samples are pellets pressed from a mixture of 4.5 g of powdered bauxite and 0.9 g of a wax as pelleting agent. The special flux distributions of the source allow irradiations at very different fast-to-thermal flux ratios without cadmium neutron absorbers. The drying and water re-uptake of bauxite and the natural radioactivity in these ores are discussed. The method was tested with several certified standards. A relative precision of 0.7% for the alumina determination was obtained for triplicate analyses. Vanadium is the only interfering element, the concentration of which should be determined separately or estimated; a correction procedure is given. 相似文献
69.
Thermodynamic properties of a solid solution, MgyU1−yO2+x, at low magnesium concentrations have been investigated using the solid galvanic cell technique. The emf values were found to vary linearly with temperature in the range 850 1050 °C, from which the linear temperature dependence of partial molar free energy of oxygen,
, and the temperature independence of
and
were derived. These thermodynamic quantities were obtained as a function of x and y. Agreement of these values with those from theoretical considerations was examined. The effect of magnesium incorporation on
was expressed using
of UO2+x as
. 相似文献
Full-size image
70.
Tatsuomi Matsuoka Takenori Tsuda Masaki Ishida † Yoji Kato Miyuki Takayanagi Takeshi Fujino Shun Mizuta 《Photochemistry and photobiology》1994,60(6):598-604
Abstract-The red pigment granule of Belpharisma japonicum is believed to be a photoreceptor organelle mediating photodispersal. Freeze-fracture and thin section electron microscopy revealed that the pigment granules contained a honeycomb-like structure constructed of folded membranes. In the fracture face of the honeycomb-like structure, small membrane particles were observed, which might correspond to pigment—protein complexes. The pigment granules were isolated and detergent-solubilized. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that the pigment granules mainly contained a 200 kDa membrane protein. The complex of red pigment and 200 kDa protein was isolated by gel-filtration chromatography of the detergent-solubilized components, and the protein was subjected to SDS-PAGE and amino acid analysis. The 200 kDa protein could not be dissociated into subunits by 2-mercaptoethanol, indicating that the protein is composed of a single polypeptide chain. Hydrophobic amino acids contained in the 200 kDa protein were not dominant, suggesting that only partial domains may extend across the membrane of the honeycomb-like structure. 相似文献