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Boris A. Trofimov Ludmila A. Oparina Lidiya N. Parshina Marina Ya. Khil’ko Anatolii P. Tantsyrev Galina P. Aleksandrova 《Cellulose (London, England)》2013,20(3):1201-1214
Diverse celluloses including non-mercerized and mercerized ones have been successfully vinylated with acetylene in the superbase catalytic systems MOH/DMSO and MOH/THF (M = Na, K) at 85–140 °C. Depending on the reaction conditions, degree of substitution of the hydroxyl groups by highly reactive polymerazable vinyloxy groups ranges 0.11–1.22, the yields of vinylated celluloses (insoluble in water, but soluble in DMSO) being 41–89 %. Vinylated celluloses are easily decomposed under the action of white rot fungi: Phanerochaete chrysosporium, Trametes versicolor and Trametes hirsutus, and can constitute a basis for the preparation of biodegradable polymer materials (due to polymerization or polyaddition at the vinyloxy group). 相似文献
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Marina Russo Filomena Cichello Carla Ragonese Paola Donato Francesco Cacciola Paola Dugo Luigi Mondello 《Analytical and bioanalytical chemistry》2013,405(13):4617-4626
In this work, a high-performance liquid chromatography with evaporative light scattering detection method has been developed and applied for quantification of the polar content of the lipid fraction in milk samples of different origin. From a chromatographic stand-point, a 4.6-mm I.D. hydrophilic interaction liquid chromatography column was employed to attain a baseline separation of major phospholipid classes contained in the various milk samples tested. Quantitative analysis was performed by the external calibration method using reference material solutions in the 5–100 mg/L concentration range. Analytical recoveries ranging from 57 to 100 %, and repeatability data lower than 8.04 % were obtained on a skimmed cow’s milk sample. The crude cow milk was the most abundant (0.04 %) in phospholipids and donkey milk was the poorest (0.004 %). Quantitative differences were determined in the phospholipid content of the milk samples tested. Finally, characterization of phospholipid profile and fatty acid composition of the different samples was carried out by an ion trap-time of flight mass spectrometer and gas chromatography coupled to flame ionization and mass spectrometry detection. A thorough screening of the polar lipid composition of milk samples of different origin is here outlined, for the first time. 相似文献
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Nikolai V. Lukashev Alexei D. Averin Protais Muhayimana Marina A. Kazankova Irina P. Beletskaya 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Addition of P-halogenophosphaalkenes to I-alkoxyalkynes provides either 2-phosphabutadienes 2 or P(II1)-substituted allenes 3. The reaction o f P-halogenophosphaalkenes I with I-aminoalkynes leads to the phosphetines 4 wa 5 - the product of 1,2-addition reaction. 相似文献
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Marina A. Khokhlova Marat O. Gallyamov Alexei R. Khokhlov 《Colloid and polymer science》2012,290(15):1471-1480
Chitosan macromolecules can be dissolved in water saturated with CO2 under high pressure, i.e. in carbonic acid. This unique biocompatible solvent with acidity regulated by the variation of applied CO2 pressure is rather promising for biomedical applications. In this work the main features of deposition of chitosan structures on the model substrate from solutions in this media were examined. After deposition on the mica surface, the obtained structures have been successfully visualised by atomic force microscopy (AFM). It has been found out that they adsorb as rather peculiar elongated objects with an average length of about 70?nm. Such conformations are believed to appear due to amphiphilic nature of chitosan semiflexible chains in agreement with recent theoretical findings. The well-defined geometry of the elongated monodispersed structures allows them to demonstrate some elements of liquid crystalline-like ordering. 相似文献
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Marina M. Carrozzo Umberto M. Battisti Giuseppe Cannazza Cinzia Citti Carlo Parenti Luigino Troisi 《Tetrahedron letters》2012,53(24):3023-3026
Chloroacylaminobenzensulfonamides regioselectively thermally cyclize under solvent free conditions to 1,2,4-benzothiadiazines with five- and six-membered rings fused on face b. 相似文献