Исследованы процессы получения наноразмерных порошков карбидов вольфрама, а также других карбидов переходных металлов с использованием плазмохимического восстановительного синтеза. Выявлены основные закономерности получения порошков заданных дисперсности и состава. Характерные размеры частиц карбидов составляли 40-80 нм. С целью получения гомогенной смеси нанопрошков WC-Со с точным массовым содержанием разработана методика осаждения кобальта на порошок карбида вольфрама с одновременным введением добавок карбидов-ингибиторов, таких как карбиды хрома, ванадия и тантала. Полученные нанопорошки исследовались с применением современных методов, в том числе растровой электронной микроскопии высокого разрешения, фракционного газового анализа. Ключевые слова: плазмохимический восстановительный синтез, нанопорошки, карбид вольфрама, карбиды-ингибиторы, кобальт, твердый сплав. The processes to produce nanosized tungsten carbide powders as well as other transition metal carbides have been investigated with the use of plasma-chemical reduction synthesis. The basic regularities of producing powders of specified dispersion and composition have been determined. Characteristic particle sizes of carbides are 40-80 nm. For the purpose of homogeneous WC-Со nanopowders mixture production with exact mass content, a technique of cobalt sedimentation onto tungsten carbide powder with simultaneous adding of retardant-carbides such as chromium, vanadium, and tantalum carbides has been developed. The produced nanopowders have been examined with modern methods including high-resolution SEM and fractional gas analysis.

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Исследован процесс адсорбции катионов железа из растворов на природном сорбенте – доломит. Получены количественные характеристики процесса адсорбции катионов железа(III). Установлена более высокая адсорбционная способность катионов железа в комбинации с термически модифицированным доломитом по сравнению с нативным фильтрующим материалом.

The vegetation evolution on the modern territory of the Ulyanovsk City and its surroundings, beginning from the late glacial period, can be presented as follows. 11,000– 10,300 years ago: a “tundra-steppe” with wormwood-mazy, horsetail, fern, shrubbygreen-green communities. 10,300–9,500 years ago: wormwood-haze-cenotic cenoses, isolated islets of sparse pine forests. 9,500–8,500 years ago: sagebrush-cerebral, cereal steppes and pine forests. 8,500–8,000 years ago: turf-grass, grass-meadow-grass meadow steppes and pine forests. 8,000–6,000 years ago: forbred-cereal, less often turfgrass meadow steppes, birch, and birch-pine forests, the appearance of deciduous species. 6,000–4,500 years ago: pine-broad-leaved, broad-leaved forests, mixed-grassgrass meadow steppes, and the maximum afforestation. 4,500–3,200 years ago: broadleaved, pine-broadleaf forests, and the appearance of agrocenoses. 3200–2500 years ago: pine, pine-birch forests, reduction of broad-leaved species, the expansion of turfgrass steppes and agrocenoses. 2,500–700 years ago: the emergence of secondary forests and meadow steppes (fescue, wormwood-cereal), the expansion of agrocenoses. 700–350 years ago: pine, pine-birch, pine-broadleaf forests, reduction of agrocenoses. 350 years ago till the present time: a sharp decline in forests, the predomination of secondary pine, broad-leaved, small-leaved, mixed forests and secondary meadow steppes, the expansion of agrocenoses and residential areas. Thus, the vegetation of the territory of the Ulyanovsk City and its environs since the late glacial period varied from the steppe one (11,000–8,000 years ago) to the forest-steppe one (8,000–700 years ago) and again to the steppe one (700 years ago – modern time). The least afforestation of the territory was observed from 11,000 to 9,500 years ago (3–4%) and from 350 years ago to the present (6–7%). The greatest afforestation of the forest-steppe was from 6,000 to 3,200 years ago, when the forest-to-steppe ratio was equal.