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71.
Natalia Monakhova Svetlana Ryabova Vadim Makarov 《Journal of heterocyclic chemistry》2016,53(3):685-709
The procedures for the synthesis of substituted pyrrolo[1,2‐a]indoles and some of their biological properties are reviewed. 相似文献
72.
Natalia Shpiro 《合成通讯》2013,43(17):2265-2269
An improved synthesis of the potent MEK inhibitor PD184352 (2-(2-Chloro-4-iodo-phenylamino)-N-cyclopropylmethoxy-3,4-difluoro-benzamide)) is herein reported. This new and reproducible protocol provides a simple and efficient way of generating gram quantities of PD184352 with minimal purification. 相似文献
73.
74.
Natalia Castro Christine Raynaud Antoine Rouilly Luc Rigal Christian Quellet 《高分子科学杂志,C辑:聚合物评论》2016,56(1):137-186
Encapsulation of flavor and aroma compounds has been largely explored in order to meet appraisal demands from consumers by improving the impact of flavor during the consumption of food products. Even though several techniques have been used for encapsulating volatile compounds, i.e., spray drying, fluidized bed coating, coacervation, and melt extrusion, those most frequently used in the food industry are spray drying and melt extrusion. In this article, the different techniques of encapsulation of flavors and fragrances in polymer-based matrices by extrusion are reviewed and partly re-defined, emphasizing the differences between the various techniques reported so far and the role of matrix types, additives, and operative conditions. Also, the role of water as a key parameter for controlled release and shelf stability of the delivery system will be discussed. 相似文献
75.
D. L. Alontseva A. V. Rusakova S. Ya. Misevra Yu. V. Ermolaev 《Bulletin of the Russian Academy of Sciences: Physics》2012,76(11):1253-1257
The effect of electron irradiation on the structure and mechanical properties of 36% Ni, 12% Cr, 3% Ti, 1% Al age-hardened austenitic steel after different modes of thermomechanical treatment, including quenching, rolling with a 99% degree of compression, and aging, is studied experimentally in the constant current mode with a fluence of 1019 freq cm?2. Regularities of the changes in the structural phase composition and mechanical properties of the investigated alloy are established as a result of electron irradiation. Scientifically grounded recommendations are given for selecting modes of thermomechanical treatment, supplemented by irradiation and ensuring the optimum combination of strength and ductility in 36% Ni, 12% Cr, 3% Ti, 1% Al age-hardened austenitic steel. 相似文献
76.
Irina V. Falina Olga A. Demina Natalia A. Kononenko Lidia A. Annikova 《Journal of Solid State Electrochemistry》2017,21(3):767-775
In this work, the results of investigation of the influence of inert binder and reinforcing fabric on structural organization and mechanism of current transfer in homogeneous and heterogeneous ion-exchange membranes are presented by theoretical analysis of parameters of the extended three-wire conductivity model. It was established that analogy in reorganization of the current paths takes place in the course of inclusion of the reinforcing fabric in perfluorinated membranes and addition of polyethylene and nylon 6 to ion-exchange resins during preparation of heterogeneous membranes. In comparison with perfluorinated membranes, the essential difference in conducting properties of heterogeneous membranes is the opportunity for the current transfer via the channel filled with equilibrium solution. The size of this channel decreases with increase in the volume fraction of the inert component inside the membrane. 相似文献
77.
Evgenyi V. Gryshkun Natalia V. Andrushko Oleg I. Kolodiazhnyi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1027-1046
Racemic chlorophosphines react stereoselectively with chiral l-phenylethylamines or amino acid esters to give diastereomerically enriched aminophosphines 3, which were isolated as diastereomerically pure crystalline borane complexes. Oxidation, thionation, the reaction with methyl iodide provide optically active derivatives of aminophosphines. (R,S)- and (S,S)-stereomers of phosphinic acid amides were separated by crystallization and a flash-chromatography. The stereochemical properties of phosphorus acid amides were investigated. The mechanism of asymmetric induction at the trivalent phosphorus atom was rationalized. 相似文献
78.
Anatoli Tchigvintsev Dmitri Tchigvintsev Robert Flick Ana Popovic Aiping Dong Xiaohui Xu Greg Brown Wenyun Lu Hong Wu Hong Cui Ludmila Dombrowski Jeong Chan Joo Natalia Beloglazova Jinrong Min Alexei Savchenko Amy A. Caudy Joshua D. Rabinowitz Alexey G. Murzin Alexander F. Yakunin 《Chemistry & biology》2013,20(11):1386-1398
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79.
Alexander Boichenko Natalia Govorukhina Ate G. J. van der Zee Rainer Bischoff 《Analytical and bioanalytical chemistry》2013,405(10):3195-3203
Macroporous reversed-phase (mRP) chromatography was successfully used to develop an accurate and precise method for total protein in serum. The limits of detection (0.83 μg, LOD) and quantification (2.51 μg, LOQ) for the mRP method are comparable with those of the widely used micro BCA protein assay. The mRP method can be used to determine the total protein concentration across a wide dynamic range by detecting chromatographic peaks at 215 nm and 280 nm. The method has the added advantage of desalting and denaturing proteins, leading to more complete digestion by trypsin and to better LC–MS–MS identification in shotgun proteomics experiments. Figure
Simultaneous Serum Desalting and Total Protein Determination with Macroporous Reversed-Phase Chromatography: calibration plots 相似文献
80.
Natalia P. Ivleva Susanne Huckele Bernadett Weinzierl Reinhard Niessner Christoph Haisch Thomas Baumann 《Analytical and bioanalytical chemistry》2013,405(28):9071-9084
We present for the first time the Raman microspectroscopic identification and characterization of individual airborne volcanic ash (VA) particles. The particles were collected in April/May 2010 during research aircraft flights, which were performed by Deutsches Zentrum für Luft- und Raumfahrt in the airspace near the Eyjafjallajökull volcano eruption and over Europe (between Iceland and Southern Germany). In addition, aerosol particles were sampled by an Electrical Low Pressure Impactor in Munich, Germany. As references for the Raman analysis, we used the spectra of VA collected at the ground near the place of eruption, of mineral basaltic rock, and of different minerals from a database. We found significant differences in the spectra of VA and other aerosol particles (e.g., soot, nitrates, sulfates, and clay minerals), which allowed us to identify VA among other atmospheric particulate matter. Furthermore, while the airborne VA shows a characteristic Raman pattern (with broad band from ca. 200 to ca. 700 cm?1 typical for SiO2 glasses and additional bands of ferric minerals), the differences between the spectra of aged and fresh particles were observed, suggesting differences in their chemical composition and/or structure. We also analyzed similarities between Eyjafjallajökull VA particles collected at different sampling sites and compared the particles with a large variety of glassy and crystalline minerals. This was done by applying cluster analysis, in order to get information on the composition and structure of volcanic ash. Figure
Images and Raman spectra of airborne volcanic ash 相似文献