Three-dimensional localized coherent structures of surface turbulence. III Experiment and model validation

The paper continues a series of publications devoted to the 3D nonlinear localized coherent structures on the surface of vertically falling liquid films. The work is primarily focussed on experimental investigations. We study: (i) instabilities and transitions leading to 3D coherent structures; (ii) characteristics of these structures. Some nonstationary effects are also studied numerically. Our experimental results, as well as the results of other investigators, are in a good agreement with our theoretical and numerical predictions.Comment: 42 pages, 15 figure

Renewable energy technologies: enlargement of biofuels list and co-products from microalgae

Microalgae is a perspective feedstock for producing a wide variety of biofuels and co-products with high added value. An alternative to the traditional technology of biodiesel from algae by the transesterification is the technology of hydrothermal liquefaction (HTL). The article presents the results of promising strains screening and directed cultivation of microalgae for the processing by means of variety of technologies and production of valuable co-products. An algorithm for selecting suitable areas for industrial plantations of algae is presented

Renewable energy technologies: enlargement of biofuels list and co-products from microalgae

Microalgae is a perspective feedstock for producing a wide variety of biofuels and co-products with high added value. An alternative to the traditional technology of biodiesel from algae by the transesterification is the technology of hydrothermal liquefaction (HTL). The article presents the results of promising strains screening and directed cultivation of microalgae for the processing by means of variety of technologies and production of valuable co-products. An algorithm for selecting suitable areas for industrial plantations of algae is presented

Estimation of microalgae resource potential for bio-oil production and sustainable rural development in the climatic conditions of Russia (the Republic of Dagestan)

The work is devoted to the estimation of microalgae resource potential for bio-oil production. We propose a method of climate and infrastructural factors spatial analysis for estimations of resource and the possibility of bio-oil production facilities construction in the study region. The resource potential depends on the area of the territory that can be used to produce biomass as feedstock for biofuel production, and equal to the amount of microalgae biomass that can be obtained on this territory. For the case study we selected the territory of the Republic of Dagestan (Russia) and microalgae Arthrospira platensis and Dunaliella salina. As an infrastructural factors, which may reduce the cost of bio-oil production we considered the following sources of cheap material resources and energy: seawater (as a source of macro- and microelements), geothermal water (as low-temperature heat source), CO2 emissions of cement plants and combined heat and power plants (as carbon source and to reduce CO2 emission). The analyses of these factors using the technology of geoinformation systems allowed to find the most suitable territories for microalgae plant allocation and therefore estimate resource potential for biooil production with maximum profit

Aluminum-Alumina Composites: Part I: Obtaining and Characterization of Powders

The process of advanced aluminum-alumina powders production for selective laser melting was studied. The economically effective method of obtaining aluminum-alumina powdery composites for further selective laser melting was comprehensively studied. The aluminum powders with 10–20 wt. % alumina content were obtained by oxidation of aluminum in water. Aluminum oxidation was carried out at ≤200 °C. The oxidized powders were further dried at 120 °C and calcined at 600 °C. Four oxidation modes with different process temperatures (120–200 °C) and pressures (0.15–1.80 MPa) were investigated. Parameters of aluminum powders oxidation to obtain composites with 10.0, 14.5, 17.4, and 20.0 wt. % alumina have been determined. The alumina content, particle morphology, and particle size distribution for the obtained aluminum-alumina powdery composites were studied by XRD, SEM, laser diffraction, and volumetric methods. According to the obtained characteristics of aluminum-alumina powdery composites, they are suitable for the SLM process