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Environmental concerns related to the implementation of circular economy has led to the development of new generations of materials. Interest in polymer composites reinforced with natural-organic/inorganic fillers is growing. Producers of polymer composites convert their production to optimize and replace traditional products with new ones with a high content of bio, recyclable materials, for sustainability and responsible actions. Research and industrial awareness are focused on ecological composites based on nat...

An environmentally safe method - metal-vapor synthesis (MVS), was applied to produce iron nanoparticles (Fe NPs), which were conjugated with the drug methotrexate (MTX). The physicochemical properties and biological activity of the generated Fe NPs-MTX nanomaterials were analyzed. Transmission electron microscopy observations indicated that Fe NPs are stabilized in the form of aggregates with a size of 100 nm. The structure of these aggregates is similar to a -bunch of grapes-, which consists of metal particles ab...

The influence of the ultrasound on corrosion resistance of chromium-dioxide silicon nano-composition electrolytic coatings (nano-CEC) in solutions of the different concentrations of nano-particles of silicon dioxide at temperatures 293, 303, 313 K has been investigated. The research showed that the electroplating of chromium-dioxide silicon nano-CEC on steel St.3 enlarges its corrosion resistance tenfold. The least corrosion resistance has nano-CEC, which got under constant ultrasound influence, and the most - whi...

A mathematical model was developed, which is based on a multivariate regression dependence and establishes the relationship between the critical pitting temperature (CPT) of the 06KhN28MDT alloy (similar to AISI 904L steel) and its chemical composition and structural components in model circulating waters with pH 4...8 and chloride concentration from 350 up to 600 mg/liter, which correspond to industrial circulating water during the operation of heat exchangers. Based on the results of the analysis of the develope...

Electrodeposition of composite coatings based on cobalt alloys from citratepyrophosphate electrolytes is investigated. The features of the co-reduction of cobalt with refractory metals (Mo, W, Zr) directly from the electrolyte solution are due to the mutual influence of thermodynamic and kinetic characteristics of alloy-forming components. Modern electrochemical technologies for surface treatment of titanium alloys to create protective, antifriction, dielectric, and catalytically active materials are considered. T...

Nanomaterials are materials with new properties that interact through complex processes at the nanometric scale that include reactions in the quantum field and which still represent an unknown for many researchers. Improving the performance of cement mortar is generally achieved with the help of various additions. Nanoparticles have recently become a material very often used in the additive of various recipes of cementitious materials and not only, because at such a size their properties change surprisingly and th...

Biopolymers have gained notoriety due to their unique physical, chemical, and mechanical characteristics and performances. Due to their regenerability, compostability, biocompatibility, non-immunogenic, non-toxic, or non-allergenic properties, they have surpassed the boundaries of the food industry and have become fundamental components in biomedicine or the pharmaceutical industry. Thus, the most well-known applications are as drug delivery systems, tissue engineering, or wound dressings. In addition to all these...

A chemical sensor of refractive index variations, which possesses prescribed resolution, is designed, implemented and tested. Enhancement of coupling forces by the Bloch surface waves is achieved by incorporating a one-dimensional (1-D) photonic crystal (PC) into the classical Kretschmann arrangement of surface plasmon resonance. The numerical optimization approach was used to establish geometrical parameters of the photonic crystal with prescribed material constituents. The number of layers, their thicknesses, an...

In recent years there has been an increase in interest in biodegradable polymers. Biopolymers are upcoming competitors for the synthetic polymers with their profound attributes like eco-friendliness and biodegradability. They can be classified as natural biopolymers, chemically synthesized biopolymers, and microbial biopolymers. One of the most widely used chemically synthesized biopolymers is aliphatic polyester polylactic acid (PLA). It is a thermoplastic derived from renewable, organic sources such as corn star...

Potential use of four types of fly ash waste as raw material for synthesis of photo- catalysts to be applied for wastewater treatment was investigated. In this respect the four selected fly ash types were subject to morphological characterization by dimensional analysis of particles and scanning electronic microscopy on to composition characterization by thermogravimetric analyses and X-ray fluorescence. Their potential to be used for advanced degradation of organic compounds via heterogeneous photocatalysis was i...

Working in stone quarrying and stone processing poses certain risks that must not be underestimated. The safety of workers must be paramount, where work-related injuries can occur, so the use of appropriate personal protective equipment is important, but the less visible risks, such as inhalation of granite stone dust, which can penetrate the respiratory tract, lungs and lung chambers, causing silicosis, chronic obstructive pulmonary disease, kidney disease or lung cancer, must not be underestimated. Chemically, g...

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...

Two-photon pulsed terahertz (THz) emission from a GaAs/AlAs double-barrier resonant tunneling diode biased into regime of self-oscillations of current has been detected. The two THz pulses are triggered at two critical points in period of current self-oscillations due to the periodic process of charge accumulation and drain in quantum well. The internal mechanism of relaxation self-oscillations, which controls the trapping and release time of electrons tunneling through the miniband, is responsible for the time de...