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Korotkikh NI Cowley AH Moore JA Glinyanaya NV Panov IS Rayenko GF Pekhtereva TM Shvaika OP 《Organic & biomolecular chemistry》2008,6(1):195-199
Four stable carbenes, 1-tert-butyl-3,4-diaryl-1,2,4-triazol-5-ylidenes 1a-d, including new fluorine-containing compounds 1c,d, react with a malonic ester to afford heterocyclic zwitterionic compounds 5a-d. The reactions with more acidic compounds (ethyl acetoacetate, malononitrile and 1,3-dimethylbarbituric acid) proceed with substrate deprotonation to form the respective azolium salts 6a-c. The X-ray crystal structure of 5a was also determined. 相似文献
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The aim of this study was to measure the shear modulus of the vocal fold in a human hemilarynx, such that the data can be related to direction of applied stress and anatomical context. Dynamic spring rate data were collected using a modified linear skin rheometer using human hemilarynges, and converted to estimated shear modulus via application of a simple shear model. The measurement probe was attached to the epithelial layer of the vocal fold cover using suction. A sinusoidal force of 3g was applied to the epithelium, and the resultant displacement logged at a rate of 1kHz. Force measurement accuracy was 20microg and position measurement accuracy was 4microm. The force was applied in a transverse direction at the midmembranous point between the vocal process and the anterior commissure. The shear modulus of the three female vocal folds ranged from 814 to 1232Pa. The shear modulus of the three male vocal folds ranged from 1021 to 1796Pa. These data demonstrate that it is possible to obtain estimates for the shear modulus of the vocal fold while preserving anatomical context. The modulus values reported here are higher than those reported using parallel plate rheometry. This is to be expected as the tissue is attached to surrounding structures, and is under natural tension. 相似文献
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Avdeenko A. P. Glinyanaya N. M. Konovalova S. A. Goncharova S. A. 《Russian Journal of Organic Chemistry》2002,38(5):692-698
Halogenation of 4-aroyl(arylsulfonyl)oxyimino-2-methyl-2,5-cyclohexadienones yields Z,E-isomeric 4-aroyl(arylsulfonyl)oxyimino-5,6-dihalo-2-methyl-2-cyclohexenones and (E)-4-aroyl(arylsulfonyl)oxyimino-5,6-dihalo-6-methyl-2-cyclohexenones. Further chlorination leads to formation of (Z,E)-4-aroyl(arylsulfonyl)oxyimino-2,5,6-trichloro-6-methyl-2-cyclohexenones. 相似文献
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A. P. Avdeenko S. A. Konovalova A. Ya. Il’chenko N. M. Glinyanaya 《Russian Journal of Organic Chemistry》2006,42(1):56-65
Halogenation of 4-aroyl(arylsulfonyl)oxyimino-2,5-cyclohexadienones is not accompanied by change of the configuration at the nitrogen atom. p-Benzoquinone oxime ethers and esters take up halogens in a regioselective fashion at the syn-C-C bond of the quinoid ring. The main factor responsible for regioselective addition of halogens is configuration at the nitrogen atom, which determines the stability of intermediate halogenonium ion. 相似文献
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COMPOSITION OF INDOOR AEROSOLS AT EMPEROR QIN''''S TERRA-COTTA MUSEUM, XI''''AN, CHINA, DURING SUMMER, 2004 总被引:2,自引:0,他引:2
Particle samples were collected in August 2004 both inside and outside Emperor Qin's Terra-Cotta Museum in Xi'an, China. Mass and chemical composition of total suspended particles (JSP, particles with aerodynamic diameter less than-30μm), PM2.5(particles with aerodynamic diameter <2.5μm) were determined. The average levels of indoor PM2.5 and TSP were 108.4 and 172.4 μg·m-3, respectively, with PM2.5 constituting 62.9% of the TSP mass. Sulfate ((32.4±6.2)%), organics ((27.7±8.0)%), and geological material ((12.5±3.4)%) dominated indoor PM2.5, followed by ammonium ((8.9±2.8)%), nitrate ((7.0±2.9)%), and elemental carbon (EC, (3.9±1.5)%). Particle size distribution varied with the number of tourists in the museum. The size of sulfate, organics, EC, nitrate, and ammonium was found to vary in the range of 0.43 to 3.3 μm in fraction. Ion balance indicated that the aerosol was acidic, with insufficient ammonium ions to neutralize the sulfuric and nitric acids. High concentrations of acidic aerosols will erode the Terra-cotta warriors and horses especially in the summer season with high temperature (30℃) and relative humidity (70%) and undesirable solar radiation inside the museum. More attention should be paid to protecting these precious antiques made 2000 years ago. 相似文献
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N. I. Korotkikh V. Sh. Saberov A. V. Kiselev N. V. Glinyanaya K. A. Marichev T. M. Pekhtereva G. V. Dudarenko N. A. Bumagin O. P. Shvaika 《Chemistry of Heterocyclic Compounds》2012,47(12):1551-1560
Carbene complexes of nickel, palladium, and copper(I) effectively catalyze the reduction of aromatic ketones under the influence
of 2-propanol in the presence of potassium hydroxide. Bis(1,3-dimethylbenzimidazol-2-ylidene)copper(I) iodide and the polymeric
complex of crown-biscarbene with copper(I) iodide show the highest catalytic efficiency. 相似文献
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An ultra-low hydrolysis sol-gel route for titanosilicate xerogels and their characterization 总被引:1,自引:0,他引:1
Toney Fernandez Gijo Jose Siby Mathew Rejikumar PR Unnikrishnan NV 《Journal of Sol-Gel Science and Technology》2007,41(2):163-168
In this work TiO2-SiO2 xerogels were prepared through an ultra low hydrolysis method using titanium and silicon alkoxide. The samples were heat
treated to 500°C. The xerogels were characterized using TGA/DTA, FTIR, XRD and TEM. The samples showed the formation of Si–O–Ti
bridges by its characteristic vibration within 925–960 cm−1 range. Si–O–Si bond angles were calculated using the central force network model. The TiO2 in all the samples crystallized on heat treatment to 500°C. The crystallite size calculated using the Scherer formula from
the XRD was verified from the Transmission Electron Micrograph. Samples heat treated to 350°C remained amorphous and hence
could be used as hosts for biomaterials and organic optical materials. 相似文献