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21.
Asanbaeva Nargiz B. Rychkov Denis A. Tyapkin Pavel Yu. Arkhipov Sergey G. Uvarov Nikolay F. 《Structural chemistry》2021,32(3):1261-1267
Structural Chemistry - The crystal and molecular structure of tris(tetrabutylammonium) pentanitratoplumbate(II) was determined and characterized by single-crystal and powder X-ray diffraction and... 相似文献
22.
Nikolay Yanshin Aleksandra Kushnareva Valeriia Lemesheva Claudia Birkemeyer Elena Tarakhovskaya 《Molecules (Basel, Switzerland)》2021,26(9)
Though numerous valuable compounds from red algae already experience high demand in medicine, nutrition, and different branches of industry, these organisms are still recognized as an underexploited resource. This study provides a comprehensive characterization of the chemical composition of 15 Arctic red algal species from the perspective of their practical relevance in medicine and the food industry. We show that several virtually unstudied species may be regarded as promising sources of different valuable metabolites and minerals. Thus, several filamentous ceramialean algae (Ceramium virgatum, Polysiphonia stricta, Savoiea arctica) had total protein content of 20–32% of dry weight, which is comparable to or higher than that of already commercially exploited species (Palmaria palmata, Porphyra sp.). Moreover, ceramialean algae contained high amounts of pigments, macronutrients, and ascorbic acid. Euthora cristata (Gigartinales) accumulated free essential amino acids, taurine, pantothenic acid, and floridoside. Thalli of P. palmata and C. virgatum contained the highest amounts of the nonproteinogenic amino acid β-alanine (9.1 and 3.2 μM g−1 DW, respectively). Several red algae tend to accumulate heavy metals; although this may limit their application in the food industry, it makes them promising candidates for phytoremediation or the use as bioindicators. 相似文献
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Vladimir V. Loza Nikolay S. Vostrikov Mansur S. Miftakhov 《Mendeleev Communications》2012,22(3):125-126
Racemic monoprotected at primary hydroxy group Corey lactones were resolved using (1S,2R,5R)-6,6-dimethyl-4-oxo-3-oxabicyclo-[3.1.0]hexan-2-ol as a chiral auxiliary reagent of hemiacylal chemotype. 相似文献
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In this paper we give a simple proof of an inequality for intermediate Diophantine exponents obtained recently by W.M. Schmidt and L. Summerer. 相似文献
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The development of theoretical ideas on the cause and the mechanism of the change of activity coefficients is the main aim of the investigation. The model describing the interaction of hydrated ions in electrolytes is proposed. In the model the electrostatic forces between ions and change of the energy of the hydrate shell in the process of ion convergence determine ions distribution in solution. The significant factor is the dependence of dielectric permittivity on the concentration of the electrolyte and on the distance to ion. The statistical approach developed allows one to calculate the influence of principal physical factors and, on this basis, to explain the nature of curves describing the activity coefficients. The results of simulation have been tested on a large number of experimental data. 相似文献
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Nonexistence of global solutions to new ordinary differential inequality and applications to nonlineardispersive equations 下载免费PDF全文
Nikolay Kutev Natalia Kolkovska Milena Dimova 《Mathematical Methods in the Applied Sciences》2016,39(9):2287-2297
A new ordinary differential inequality without global solutions is proposed. Comparison with similar differential inequalities in the well‐known concavity method is performed. As an application, finite time blow up of the solutions to nonlinear Klein–Gordon equation and generalized Boussinesq equation is proven. The initial energy is arbitrary high positive. The structural conditions on the initial data generalize the assumptions used in the literature for the time being. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Alexey V. Laptev Dmitrii E. Pugachev Alexey Yu. Lukin Andrei V. Nechaev Nikolay E. Belikov Olga V. Demina Petr P. Levin Andrey A. Khodonov Andrey F. Mironov Sergei D. Varfolomeev Vitalii I. Shvets 《Mendeleev Communications》2013,23(4):199-201
A new 5,10,15,20-tetrasubstituted porphyrin containing four 6’-nitro-1,3,3-trimethylspiro(indolino-2,2’-2H-chromene) substituents and its complexes with Zn2+ and Cu2+ ions were prepared and characterized by physicochemical methods of analysis. 相似文献