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The Central Taimyr accretionary belt includes two granite-metamorphic terranes: Faddei and Mamont-Shrenk, which include the oldest igneous formations of the Taimyr folded area in the Arctic framing of the Siberian craton—granitoids and granite-gneisses with U–Pb zircon ages of 900–830 Ma. The [FeO^*/(FeO^* + MgO)] — enriched granitoids of these terranes are products of highly fractionated I -type magmas. This paper presents results of new petrographic, geochemical, geochronological, and paleomagnetic investigations of acid rocks fr om a volcanic-plutonic association (in the region of the Leningradskaya River) in the Faddei terrane in the northeastern Taimyr area. These rocks formed during the final stage of continent–island arc accretion and collision that occurred at approximately 870–820 Ma. We established that the studied rocks belong to a long granitoid belt extending from Mamont-Shrenk to Faddei terrane, wh ere all the igneous bodies are deformed and oriented uniformly. The paleomagnetic pole we calculated differs significantly from the apparent polar-wander path interval of corresponding age for Siberia. The 33.8° ± 5.4° angular distance between the poles indicates that the formation of this volcanic-plutonic association took place at a significant distance from the Taimyr margin of the Siberian paleocontinent.

At the Center of Isotope Studies of the A.P. Karpinsky Russian Geological Research Institute, the structure and isotope composition of zircons from two granitoid complexes, the age of their sequential growth zones, and the hosted inclusions have been studied using a SHRIMP-II ion mass spectrometer. The zircons consist of deformed cores with crystalline melt inclusions and of shells: inner, with glassy, partly devitrified inclusions, and outer metamorphogene, with fluid inclusions. Judging from the zircon zoning, crystallization of melts of both complexes proceeded in several stages: (1) The generation of melts and the beginning of zircon core growth (505 and 493 Ma) were synchronous with the overthrusting in the Ol’khon region; (2) The rapid ascent of melts (the inner shell, 479 and 475 Ma) together with the host rocks was caused by upthrust faulting and shear dislocations; (3) The metamorphogene shell (456 Ma) reflects the second stage of metamorphism. At the same time, the Shara-Nur migmatite–granite complex corresponds in composition, structures, and textures to syncollisional K-granites, whereas the differentiated Khaidai gabbro-diorite–diorite–granodiorite–granite complex is close in geochemical features (similar to those of the Anga sequence metavolcanics) and the mantle (juvenile) source of substance to the recent island-arc magmatism. It is suggested that the Caledonian island-arc magmatism was close in time to the accretion of the sediments of back-arc basin (Ol’khon Group) to the continental margin, on the one hand, and to the island-arc block, on the other.

The reaction of 6'-aminodubamine (2-(4',5'-methylendioxy-2';-aminophenyl)-quinoline) with various aliphatic acids was studied. Amides were obtained in the yields of 23.0-64.9 %. The structure of amides was established on the basis of the analysis of spectral data and X-ray diffraction analysis. The antimicrobial activity of the obtained amides was studied.

The early data on the distribution and the forms of uranium and thorium migration in different geochemical types of natural waters of the Baydar Valley (the Crimean Peninsula) are obtained. Fresh and ultrafresh waters, mainly with hydrocarbonate calcium composition with total dissolved solids from 208 to 1269 mg/dm³, widely occur in the region. Fracture-karst waters, which are best protected from the continental salination, relate to weakly alkaline (pH 7.7), fresh with total dissolved solids 444 mg/dm³, and not very high Si concentrations (2.23 mg/dm³), hydrocarbonate calcium by composition. The waters of the zone of regional fracturing and fissure-vein waters are prone to the influence of continental salination processes and anthropogenic load. They are characterized by pH from neutral to alkaline (7.1-8.6); they are mainly fresh (269-1269 mg/dm³), with average Si content of 4.61-4.70 mg/dm³, their composition is hydrocarbonate calcium with increased concentrations of SO₄^2-, Mg²⁺ and Na⁺. The surface waters are prone to continental salination; they are weakly alkaline (рН 8.3), moderately fresh (207-364 mg/dm³), with the average Si concentration of 1.18 mg/dm³, hydrocarbonate calcium composition and increased concentrations of Cl^-, Mg²⁺ and Na⁺. The determined concentrations of uranium (²³⁸U) vary within the range from 2.64 • 10^-5 to 2.25 • 10^-3 mg/dm³, thorium (²³²Th) - from 2.04 • 10^-7 to 2.50 • 10^-5 mg/dm³. The nature of radioactivity of the studied objects is due to ²³⁸U, because the waters are characterized by the oxidative parameters of the geochemical environment with pH 7.1-8.9, Eh 67.2-209.3 mV and the concentration of dissolved oxygen 3.19-12.25 mg/dm³. The ratio ²³²Th/²³⁸U is (1.09 • 10^-3)-0.71. Waters enriched with ²³⁸U to the highest extent are the waters of regional fracturing zone, mainly related to sodium aluminosilicates, subjected to continental salination under the conditions of anthropogenic impact, and waters enriched with ²³²Th are those of the regional fracturing zone, mainly related to sodium silicates (long-term interaction in the water - rock system) subjected to continental salination. ²³⁸U migrates in the form of anion complexes UO₂(CO₃)₃^4- and UO₂(CO₃)₂^2-, to a lower extent (<1 % of the total content) in the form of Ca₂UO₂(CO₃)₃(aq) and CaUO₂(CO₃)₃^2-. Results of calculations over ²³²Th revealed its presence only in the form of complex Th(OH)₃CO₃^-.

This review combines and clarifies data from studies which have examined the chemical composition and pharmacological properties of Polygala sibirica L. Detailed information on molecular diversity is presented, including selected structural formulas. These include: xanthones, triterpene saponins, new flavonol glycoside compounds, acetophenones, phenolcarboxylic acid derivatives, and other secondary metabolite groups. Data from studies examining the antioxidant, antibacterial, and other types of biological activity of extracts, their fractions, or individual components are also presented. The overall data confirm the possibility of using P. sibirica as an additional source of medicinal raw materials.

The component composition of the chloroform fraction of the ethanol extract of Dictamnus angustifolius plant of the Rutaceae family , collected in the Tashkent Region of the Republic of Uzbekistan, is investigated. Alkaloids skimmianine, γ-fagarine, haplamine, and the new base angucine were isolated using column chromatography as a separation method. The obtained compounds were identified by means of ¹Н, ¹³С NMR, IR Fourier spectroscopy, and X-ray diffraction analysis.

The content of reserve and biologically active substances in the leaves and rhizomes of the Regal Air variety of Hemerocallis hybrida species cultivated in the Central Siberian Botanical Garden, in the forest-steppe zone of Western Siberia, was determined. Comparative data on the specific features of the accumulation of reserve substances (sugar, starch), phenolic compounds (catechins, flavonols), pectin substances (pectins, protopectins), saponins, and ascorbic acid in the vegetative organs of this variety during the years 2013-2015 are presented. An increase in the content of ascorbic acid in the leaves by the fruiting period by a factor of 1.2-2.5 was determined, depending on the growing season. The highest content of ascorbic acid in the leaves was determined in 2014, varying from 81.30 • 10^-3 to 202.91 • 10^-3 %. A stable concentration of flavonols in the leaves (0.75 - 0.83 %) was detected during the growing season of 2015. The highest amount of saponins in the rhizomes was detected during the spring growing season and fruiting, which was 2 times more than in the leaves. The high content of catechins (0.89-1.00 %) was detected in the leaves of the Regal Air variety during the early summer growing period. The amount of starch in the rhizomes in different phenophases and years of development varied from 24.12 to 43.54 %. It was determined that the content of ascorbic acid, sugars, flavonols is higher in the leaves than in the rhizomes, while the rhizomes contain higher amounts of starch, pectins, protopectins, saponins. The content of reserve and biologically active substances in the leaves and rhizomes of H. hybrida , Regal Air variety, adapted to the conditions of the forest-steppe zone of the Novosibirsk Region, depends on the features of development and the year of vegetation of the plants.

A brief review of low molecular weight compounds used to impart antibacterial properties to polymeric materials is presented. The main methods of introducing these compounds into the structure of polymers are considered. The prospects for the use of various antibacterial agents are analyzed from the point of view of creating materials capable of acting on antibiotic-resistant strains of microorganisms.

For geochemical typification of oils and condensates from the fields of the Tambey group (the Yamal Peninsula) and determination of their assumed sources, the data on the organic geochemistry of the major oil-gas-source rock masses were generalized and compared with the results of geochemical interpretation of the analytical data on the composition of the studied naphtides. In accordance with the genetic hydrocarbon indicators (concentration ratios based on the composition of n -alkanes, acyclic isoprenanes, steranes, terpanes) and with the isotopic composition of carbon, three genetic types of naphthides are distinguished in the considered collection. The mixed genotype predominates, one sample corresponds to the aquagene genotype, and several samples correspond mainly to the terragenic genotype. Maturity indices with respect to the composition of steranes, terpanes and arenes provide evidence of the formation of the analyzed samples under the conditions of the main oil generation zone. Relying on gas-liquid chromatographic data (the naphthenic hump, the absence of n -alkanes or their lower content compared to acyclic isoprenanes), condensates from the Albian-Cenomanian and, partially, from the Aptian deposits underwent microbial oxidation of the moderate and initial stages, respectively. The features of the physicochemical properties indicate the condensation type of most of the studied samples. This is consistent with the localization of the deposits in the zone of predominant gas-condensate accumulation.

Procedures for the control of iron content at all stages of the mechanochemical synthesis of lithium aluminates were developed. The procedures were proposed to determine iron content using two independent methods: molecular and atomic spectroscopy. Atomic absorption spectrometry should be used for iron content lower than 10^-3 mass %, as well as for aluminium-containing samples. It was found that lithium content in the sample up to 1 g/L does not affect the analytical signal of iron in the sample with iron concentration 2-5 µg/mL of iron when analyzing lithium carbonate by means of atomic absorption.