Obtaining of Carbon Nanotubes in Reactor with Fluidized Bed of Catalyst

The researching activity related to CNTs has grown most significantly over the past 10 years. Since 2006, world capacities of production of CNTs have increased 10-fold. The annual number of scientific publications on CNT and issued patents continues to grow [1]. Carbon nanotubes are used in many areas, such as energy, biotechnology, microelectronics, textiles, etc...

RECENT ADVANCES AND CHALLENGES OF CURRENT COLLECTORS FOR SUPERCAPACITORS

Global energy and environmental issues are driving the development of modern advances in efficient and environmentally friendly energy storage systems. Such systems must meet a range of requirements, which include high energy and power density, long service life, flexibility, industrial scalability, security and reliability. Progressive achievements in the field of energy storage are associated with the development of various kinds of batteries and supercapacitors. Supercapacitors are state-of-the-art energy storage devices with high power density, long lifespan, and the ability to bridge the power/energy gap between conventional capacitors and batteries/fuel cells. However, supercapacitors have limitations associated with low energy density, which can be solved by using various types of current collectors, since current collectors are one of the main massive components of supercapacitors. This review gives a complete understanding of the effect of current collectors on the actual performance and properties of supercapacitors. We reviewed current collectors based on carbon and metal-containing materials, and supercapacitor configurations to identify possible improvements in electrochemical performance in terms of specific capacitance, energy density, power density, service life and variability in their application

Obtaining of Carbon Nanotubes in Reactor with Fluidized Bed of Catalyst

The researching activity related to CNTs has grown most significantly over the past 10 years. Since 2006, world capacities of production of CNTs have increased 10-fold. The annual number of scientific publications on CNT and issued patents continues to grow [1]. Carbon nanotubes are used in many areas, such as energy, biotechnology, microelectronics, textiles, etc...

Fire-induced changes in soil and vegetation in the forest-tundra of Western Siberia

Wildfires are one of the main factors for landscape change in tundra ecosystems. In the absence of external mechanical impacts, tundra plant communities are relatively stable, even in the face of climatic changes. In our study, lichen cover was degraded on burnt tundra sites, which increased the permafrost thaw depth from 100 to 190 cm. In old fire scars (burnt 1980 – 1990) of the forest-tundra, vegetation cover was dominated by trees and shrubs. The soil temperature on burnt forest-tundra sites was higher in comparison to conditions of the unburnt control sites and permafrost was was not found at a depth of 2-2,3m. Dynamics of the Normalized Difference Vegetation index (NDVI) from 1986-2020 reveal that immediately after fires, vegetation recovered and biomass increased due to the development of Betula nana shrubs. In old fire scars of the forest-tundra (burnt 1980-1990), a significant increase in NDVI values was evident, in contrast to the unburnt tundra vegetation where this trend was less pronounced. We conclude that "greening" in the north of Western Siberia may occur due to fire-induced transformation processes. The role of wildfires in the advance of the treeline to the north, driven by climate change and active economic development of the Arctic, will gradually increase in future

Исследование влияния наложения электрического поля и катализаторов на гидрофобные свойства сажи, образующейся в пропан - воздушном пламени

В предлагаемой работе исследованы влияния внешних воздействий на гидрофобные свойства сажи, образующейся в пропан - воздушном пламени. При исследовании образцов сажи на гидрофобность было обнаружено, что электрическое поле и катализатор положительно влияют на гидрофобное свойства полученной сажи. Определено, что при наложении электрического поля и катализатора на пламя образовавшаяся сажа имеет супергидрофобные свойства, т.е. угол смачивания составлял 152-153°. Положительное влияние электрического поля и катализатора на гидрофобные свойства полученной сажи можно объяснить наличием наносферических структур и их близким расположением друг от друга. Для получения полной информации о структуре полученная сажа была исследована физико-химическими методами (комбинационное рассеяние света, электронная микроскопия)

Major, Trace and Rare Earth Element Distribution in Water, Suspended Particulate Matter and Stream Sediments of the Ob River Mouth

Ongoing climatic changes are influencing the volume and composition of the river waters that enter the Arctic Basin. This hydrochemical study was conducted within the mouth of the Ob River, which is one of the world’s largest rivers, providing 15% of the Arctic Ocean’s total intake. Concentrations of suspended and dissolved elements were determined using ICP–MS and ICP–AES. As compared to the world average values, the Ob river water had higher concentrations of dissolved P, As, Cu, Zn, Pb and Sb, i.e., the elements that form soluble organo-mineral complexes. The composition of suspended matter was characterized by low concentrations of most trace elements (Cd, Cr, Co, Cu, Mo, Al, Ni, Pb, V) due to their low contents in peat soils within the river drainage basin. Concentrations of dissolved forms were many times lower than concentrations of suspended forms in Al, Fe, Mn, Zn, Cr, Co, Ti, Sc, and all rare earth elements. Total concentrations of Ni, Cu, Bi, Pb, W in the river water increased by 2.5 to 4.2 times during the summer. The effects of climate change, which can cause an increase in the discharge of solid particles from thawing permafrost, are likely to lead to an increase in the discharge of certain elements into the Ob River estuary