10 research outputs found
Drivers and barriers for implementation radical and incremental innovation in subsea complex in Russia
Master i Energy Management - Nord universitet, 2017Sperret til 2020-10-0
Some Elements of Biologization in Crops Production on Radioactively Contaminated Areas
The modern environmental and biological approaches to the selection of field agricultural crops for cultivation at contaminated areas are considered. It is established that the satiation of rotations with agricultural crops differed by potentially low capacity to accumulate 13Cs can significantly extend the areal of radioactively contaminated lands use for the production of safe products. The influence of arbuscular mycorrhizal fungi on radiocaesium uptake by plants is analyzed. The ability of arbuscular mycorrhiza to modify significantly radiocaesium accumulation by agricultural crops is found
Some Elements of Biologization in Crops Production on Radioactively Contaminated Areas
The modern environmental and biological approaches to the selection of field agricultural crops for cultivation at contaminated areas are considered. It is established that the satiation of rotations with agricultural crops differed by potentially low capacity to accumulate 13Cs can significantly extend the areal of radioactively contaminated lands use for the production of safe products. The influence of arbuscular mycorrhizal fungi on radiocaesium uptake by plants is analyzed. The ability of arbuscular mycorrhiza to modify significantly radiocaesium accumulation by agricultural crops is found
Low-temperature CO oxidation over Ag/SiO2 catalysts: Effect of OH/Ag ratio
Combined application of TPx methods, H2βO2 titration, UVβvis DRS, TGAβDSCβMS, TEM, XRD, N2 adsorption at β196 oC allowed proving the OH/Ag molar ratio as the key parameter defining the catalytic properties of silica-supported silver (Ag/SiO2) in lowβtemperature CO oxidation. A new insight into the formation of active species on the catalyst surface is presented. In this study, Ag/SiO2 catalysts with Ag loading of 5 and 8 wt.% were prepared by incipient wetness impregnation method on the basis of commercial silicas preliminary calcined at 500, 700 and 900 Β°C. Detailed characterization of catalysts by physicochemical methods revealed that molar ratio between the concentration of surface OH groups (normalized to support mass) and silver amount in the prepared catalysts (OH/Ag ratio) affects the silver dispersion, structure of silver nanoparticles (NPs) and their catalytic properties. Only at optimal value of OH/Ag ratio the silver NPs are stated to possess both high dispersion and defective multidomain structure (that consists of several nanodomains) providing the adsorption of weakly bound oxygen species responsible for high catalytic activity in CO oxidation at lowβtemperature. Additionally, the co-existence of two types of active sites reacting with CO at room temperature with and without formation of adsorbed carbonate species is discussed. The first type of active sites was catalytically active in low-temperature CO oxidation with CO2 release at room temperature (RT). The second type may retain surface carbonate species up toββΌ40β50 Β°C. The balance between these species shifts towards the first type for the active catalyst
Low-temperature CO oxidation over Ag/SiO2 catalysts: Effect of OH/Ag ratio
Combined application of TPx methods, H2βO2 titration, UVβvis DRS, TGAβDSCβMS, TEM, XRD, N2 adsorption at β196 oC allowed proving the OH/Ag molar ratio as the key parameter defining the catalytic properties of silica-supported silver (Ag/SiO2) in lowβtemperature CO oxidation. A new insight into the formation of active species on the catalyst surface is presented. In this study, Ag/SiO2 catalysts with Ag loading of 5 and 8 wt.% were prepared by incipient wetness impregnation method on the basis of commercial silicas preliminary calcined at 500, 700 and 900 Β°C. Detailed characterization of catalysts by physicochemical methods revealed that molar ratio between the concentration of surface OH groups (normalized to support mass) and silver amount in the prepared catalysts (OH/Ag ratio) affects the silver dispersion, structure of silver nanoparticles (NPs) and their catalytic properties. Only at optimal value of OH/Ag ratio the silver NPs are stated to possess both high dispersion and defective multidomain structure (that consists of several nanodomains) providing the adsorption of weakly bound oxygen species responsible for high catalytic activity in CO oxidation at lowβtemperature. Additionally, the co-existence of two types of active sites reacting with CO at room temperature with and without formation of adsorbed carbonate species is discussed. The first type of active sites was catalytically active in low-temperature CO oxidation with CO2 release at room temperature (RT). The second type may retain surface carbonate species up toββΌ40β50 Β°C. The balance between these species shifts towards the first type for the active catalyst
Effect of small-scale wildfires on the air parameters near the burning centers
The results of seminatural experiments on the study of steppe and field wildfires characteristic of the steppe and forest-steppe zones of Western Siberia are presented. Using infrared (IR) thermography methods, the main thermal characteristics of the fire front are derived, the flame turbulence scale is estimated, and changes in the structure function of the air refractive index are analyzed in the vicinity of a fire. The effect of a model fire on the change of meteorological parameters (wind velocity components, relative air humidity, and temperature) is ascertained. Large-scale turbulence is observed in the front of a seminatural fire, which is absent in laboratory conditions. The predominance of large-scale turbulence in a flame results in turbulization of the atmosphere in the vicinity of a combustion center. Strong heat release in the combustion zone and flame turbulence increase the vertical component of the wind velocity and produce fluctuations in the air refractive index, which is an indicator of atmospheric turbulization. This creates prerequisites for the formation of a proper wind during large fires. Variations in the gas and aerosol compositions of the atmosphere are measured in the vicinity of the experimental site