Data on the thermodynamic analysis of the chemical affinity values of the oxides of the elements that constitute titanium-containing concentrates with respect to fluorinating reagents (HF, NH
4
F, NH
...4
HF
2
) and on the thermochemical reaction processes of silicon dioxide, various dispersions, and ammonium hexafluorotitanate upon steam heating are provided. The predominant formation of ammonium hexafluorosilicate, which binds the products of pyrohydrolysis of titanium salts upon formation, sublimates at a temperature of 250–300°C, is captured outside the pyrohydrolysis zone, and reduces the temperature of pyrohydrolysis, is confirmed and recommended for application in the hydrofluoride technology used in the production of titanium dioxide. Data on the morphology of titanium dioxide powders are obtained.
Here, we applied direct laser-induced periodic surface structuring to drive the phase transition of amorphous silicon (a-Si) into nanocrystalline (nc) Si imprinted as regular arrangement of Si ...nanopillars passivated with a SiO
2
layer. By varying the laser beam scanning speed at a fixed pulse energy, we successfully tailored the resulting unique surface morphology of the formed LIPSSs that change from ordered arrangement of conical protrusions to highly uniform surface gratings, where sub-wavelength scale ripples decorate the valleys between near-wavelength scale ridges. Along with the surface morphology, the nc-Si/SiO
2
volume ratio can also be controlled
via
laser processing parameters allowing the tailoring of the optical properties of the produced textured surfaces to achieve anti-reflection performance or partial transmission in the visible spectral range. Diverse hierarchical LIPSSs can be fabricated and replicated over large-scale areas opening a pathway for various applications including optical sensors, nanoscale temperature management, and solar light harvesting. By taking advantage of good wettability, enlarged surface area and remarkable light-trapping characteristics of the produced hierarchical morphologies, we demonstrated the first LIPSS-based surface enhanced fluorescent sensor that allowed the identification of metal cations providing a sub-nM detection limit unachievable by conventional fluorescence measurements in solutions.
Unique hierarchical laser-induced periodic surface structures (LIPSSs) enable the detection of metal ions at sub-nM concentrations
via
surface-enhanced fluorescence.
The development of drilling waste recycling technologies is a crucial task, primarily due to their negative impact on the environment, the increasing need for state control over compliance with ...environmental legislation by oil production companies, and the absence of universal technological solutions for their recycling and neutralization. This article provides a brief overview of various methods to recycle drilling waste for the production of different materials. Using drilling waste located in the Tyumen region as an example, the study demonstrates the potential of incorporating them as additives in fine-grained concrete.
The paper describes a method for processing microimages of thermochemical laser-induced periodic surface structures (TLIPSS) to quantify their structural order and defects. Results of its application ...for the analysis of microimages of periodic structures formed in 30-nm chromium films by an astigmatically focused femtosecond Gaussian laser beam have been presented. Dependences of the relative area of the beam-modified region, the area of defects, and the ordering of the periodic structures on the scanning speed and the writing beam power have been obtained.
A prototype of a dual-frequency aviation synthetic aperture radar station for remote sensing of the Earth, suitable for use on light-engine and unmanned aerial vehicles, is described. The system's ...concept, main technical solutions, and results achieved in the creation of onboard equipment are considered. The results of flight tests of the SAR prototype carried out in 2019 are presented. The characteristics of the radar survey are described. Possible ways of further development of the system are discussed.
Coating formation on titanium and aluminum samples in aqueous electrolytes at breakdown potentials (under conditions of microarc oxidizing) is described. The oxidizing was performed with either no ...current restriction during the oxide film breakdown or with an additional reactive resistance in the external circuit allowing to control the energy input intensity to the breakdown channels. It is shown that the external reactive resistance increases the coating formation potentials with no visible additional breakdown areas; the final coating formation currents decrease by order of magnitude; the energy evolved in the electrolyte decreases by a factor of 5 to 10. The variable external reactive resistance allows forming coatings with novel properties.PUBLICATION ABSTRACT
A class of hybrid systems (HS) is considered. Architecture of instrumental environment for simulation of hybrid systems is presented. Examples of textual and graphical computer models of HS are ...given. Description of main integration algorithms involved in numerical methods library is given. Approach for choosing the integration stepsize is offered. This approach takes into account the complex conditions for the existence of modal behavior and dynamics of event functions.
A model of the energy propagation in a material under a pulse effect is suggested according to which the speed of the phonon spreading (the speed of sound in the material) is one of the basic ...criteria to estimate the erosion of the electrode in the case of an electric breakdown. There has been carried out a comparative analysis of the losses through the erosion of electrodes calculated by this model and the data obtained by B.N. Zolotykh 17. It has been shown that the pressure arising between the material’s particles when a certain energy is transferred to the material is inversely proportional to the particles’ size and can be described by the equation for ideal gases.
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