The active development of additive technologies ensures prompt response to production needs, which contributes to the development of safe and environmentally friendly materials. The focus is on environmentally friendly, rapidly renewable resources with reinforcing properties. The high content of SiO2 in plant waste and the possibility of their chemical modification for use as fillers allow the creation of composite materials with high physical and mechanical properties. This paper examines the possibility of 3D printing a product using the FDM (Fused Deposition Modeling) method from a filament, which consists of a composite material based on a biodegradable thermoplastic polymer (polylactide) and a filler (modified oat husk). The filament was obtained by extrusion. The threads (filament) were tested for tension, and laboratory samples with the best results were printed on a 3D printer for further bending and strength tests. As a result of the work, laboratory samples were produced from a filament consisting of a highly filled composite material based on PLA and a chemically modified filler with high physical and mechanical properties.

The paper presents results of researches of way of increase in exit of effective hi-tech large-size articles from quartz ceramics in the conditions of mass production by means of completion of surface defects are stated.

The results of the analysis of calculated values of dusting intensities for two size intervals 0–10 μm (I interval) and 10–20 μm (II interval) on discrete spatially spaced twenty dusty sites are presented. A three-dimensional model of the region the “ANOF-2 tailing dump — Apatity city” was used. This model was developed on the basis of a non-specialized COMSOL code and supplemented with consideration of buoyancy and background stratification mechanisms. The following values of the variable parameters of the model were used when performing numerical experiments using a proven technique: wind velocity of 5 and 11 m/s, background stratification parameter from –0.05 to +0.05 in increments of 0.01 °C/m. It has been demonstrated that only at a wind velocity of 11 m/s, dust of both size intervals participates in the process of atmospheric pollution, at a wind velocity of 5 m/s, dust rise of the I interval is not predicted. An increase in wind velocity from 5 to 11 m/s reduces the maximum variation in dust intensity values with variations in background stratification from ~10 to ~2 %. Further strengthening of the wind minimizes the effect of variation of the stratification parameter on the dusting intensity to almost zero.

The electrochemical oxidation process of W-Re alloy waste (using VR-26 alloy (weight %: 74 W, 26 Re) as an example) under the action of direct and symmetrical sinusoidal alternating current of industrial frequency (50 Hz) with changing current density (0,5 ÷ 2,0 A/cm2) and electrolyte temperature (20 ÷ 50 °C) in an aqueous solution of ammonium carbonate (0,5 ÷ 1,0 M) was investigated. It was found that the use of direct current under optimal conditions ensures high-speed dissolution of the alloy (~22 kg/m2·h), while the use of alternating current makes it possible to synthesize microdispersed tungsten-rhenium oxide powder. A fundamental process flowchart for producing W-Re powder using an electrochemical method is proposed. The fundamental process flowchart ensures a ~50% recovery of tungsten and rhenium from waste into powder.

The distribution coefficients of REE (Y, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb) in the P507-CYANEX 272-Isopar L-isooctanol-HCl system were determined in the concentration range: HCl from 0.5 to 4 mol/dm3, P507- CYANEX 272: 15, 30 and 50 % by weight at a temperature 298 K. The aqueous phase contained a mixture of REE chlorides obtained after separation of light REE (La-Sm) from a concentrate obtained from loparite at the Solikamsk magnesium plant.

The article presents the results of the extraction of zirconium from high-level waste and spent nuclear fuel cladding. Zirconium is a promising metal that is widely used in various industrial fields, including the nuclear industry.

Perovskite concentrate (PC) contains such valuable components as titanium, niobium, tantalum, and rare earth elements (about 55 % by oxides). An undesirable impurity in PC is radioactive components (RAC) which are one of the main obstacles in advancing the technology to industrial implementation. As numerous studies show, RAC can be effectively separated by the interaction of PC with nitric acid. Oxides of rare earth elements, calcium, and titanium, niobium, and tantalum form the solid phase together with thorium. In our opinion, nitric acid treatment should be carried out in an autoclave. Its conditions ensure the formation of a crystalline precipitate of titanium, a rare metal. This precipitate primarily contains rutile. Rutile is a precursor and is effectively used in chloride technology for titanium and titanium-rare metal raw materials to produce metallic titanium and rare metal compounds.

The promising methods of preliminary activation of spodumene concentrate are shown (mechanoactivation, energy impact, high-frequency electromagnetic processing). An increase in the reactivity of α-spodumene was found during sulfatization of activated spodumene concentrate.

This study presents the results of risk assessment regarding the impact of synthetic analogs of the titanosilicate minerals lintisite, zorite, ivanyukite, sitinakite, and natisite on living organisms. This was achieved through experiments using a solution that simulates the composition of artificial blood plasma (in vitro model) and the fruit fly Drosophila melanogaster (in vivo model).

In the article was considered species composition of fish in the littoral and sublittoral zones of Yarnyshnaya and Zelenetskaya bays (Barents Sea) during summer 2022. Also quantitative characteristics of the distribution for each fish species are represented. The dynamics of abundance and diversity of coastal fish communities were analyzed. At whole was discovered 12 species of fish and most abundent between them is young saithe Pollachius virens. Comparing of perennial data with 2022 indicates that at the present observed average species composition, fish distribution density, abundance of young Gadidae and indicators of biodiversity in coastal communities.