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This study investigates the transport dynamics of heavy metals and metal-containing nanoparticles from mining-affected areas through major Georgian river systems into the Black Sea, with a focus on environmental risk assessment. Mining activities in Georgia represent a significant source of metal contamination, influencing both dissolved and particulate phases within riverine environments. A spatial monitoring approach was applied along upstream–downstream gradients to evaluate the distribution of metals in wate...

The issue of improving the shape of paraboloidal surfaces of transformable reflectors is still considered one of the most challenging problems. In modern transformable reflectors, the paraboloidal shape of the center of deployable reflectors is ensured by placing nodes of a flexible tape grid. It is accepted that the maximum accuracy of the parabolic surface is achieved under conditions of equal loads of the nodes. Changes in the geometry of the paraboloidal surface of the reflectors mainly develop in the peripher...

High-Entropy Alloys (HEAs) have higher mixing entropy than the conventional alloys and intermetallic compounds and form the stabile solid solutions with disordered structure. They exhibit unique and special properties, in particular high hardness, wearresistance, significantly high strength, structural stability, good corrosion, and oxidation-resistance. HEAs -exotic-, core effects are followings: high configurational entropy; sluggish diffusion; lattice distortion and cocktail effect. At the current stage, the vo...

Environmental pollution from polymer waste is one of the severe ecological problems. As of today, each day, approximately eight million pieces of plastic waste reach the ocean, where they are transformed into microplastics (small particles). Organisms in the sea are eating microplastics. The harmful effects of garbage ultimately affect humans. Due to the magnitude of the problem, the demand for biodegradable, eco-friendly materials, which will decompose after the operational period and will not pollute the environ...

In order to protect the structural steel sheet from the impact of the blast wave, the steel sheet was covered with a composite material consisting of aramid fabrics with a surface density of 200 g/m2 (3 layers) and 350 g/m2 (3 layers). The total thickness of these layers was 2.4 mm. Turkish produced BRE 450 polyester resin was used to connect the layers. The composite was coated on top with the same resin filled with crumb rubber 1.5 mm in size. The thickness of this coating is 2.2 mm. The protective agent thus ob...

Nowadays, along with creating materials with enhanced mechanical characteristics, it became important in the light of ecological problems, to design eco-friendly materials capable to disappear with time after fulfilling functions, in other words to develop biodegradable mechanically strong materials. The chemistry and technology of biodegradable polymers is one of the most important and rapidly developing fields of modern polymer science. A lot of biodegradibel polymers (BPs) were created mostly for medical applic...

One of the significant problems in terms of the mining impact on environment is abandoned (due to various factors) deposits and tailings accumulated on landfills. In addition, one of the most important resources for the development of mining is the inclusion of raw materials (as non-industrial stocks) in the economy. There are two ways to solve these problems: a) to achieve economic profitability of the deposit by improving the technologies of extraction and processing of basic raw materials, and b) to develop inn...

On the base of unsaturated polyester resin and nano powder fillers, polymer concrete (PC) was produced applicative in aggressive underground conditions. The curing agents of the resin for the polyester resin were Akcobalt 6% (cobalt 2-ethylhexanoate mixture) and Akperox A1 (Methyl Ethyl Ketone Peroxide-MEKP). Ultrafine powder was produced by grinding of a coarse mixture on the PULVERISETTE 7 premium Line planetary mill by a dry method. Selection and designation of concentrations of aggressive media - sodium sulfat...

Storage, protection and recycling of explosives, gunpowder and rocket fuel obtained from utilized ammunitions is significant problem. It requires, special services for safety and corresponding additional expenses on security and ecology. Same time, they are energetic materials and attractive for chemical and mining industry. One of the main directions for solving the above-mentioned problems is application of utilized ammunition for development of new industrial explosives for mining industry. Implementation of ne...

The frequency of development contemporary technologies is strongly connected to the creation of new composite materials with multi-functional application. They should be characterised with all necessary complex properties for functioning in extreme conditions. The radiation materials science has one of the important segments among the huge spectrum in materials science. Ther e is much interest in above mentioned materials in nuclear technologies. In particul ar, there are increased requirements in key- segments in...