Исследовано влияние полисульфона ПСФ-150 на ударную вязкость эпоксидной смолы ЭД-20 в диапазоне температур от -60 до + 20 °С. Показано, что модифицированная полисульфоном эпоксидная смола, обладает повышенной ударной вязкостью и сохраняет преимущество над не модифицированной во всем диапазоне температур испытаний. Система с фазовой структурой, содержащей непрерывную фазу термопласта, вносит значительный вклад в увеличение ударной вязкости модифицированной матрицы.

A heterophase method with elements of mechanical activation for producing mesoporous hydroxyapatite (HA) was proposed and tested. Optimal synthesis conditions conducting were determined. The obtained materials were studied by X-ray phase analysis (XRD) and IR spectroscopy, and their area of specific surface (BET method), pore volume, and pore size distribution (based on the BJH model) were determined. Optimal synthesis conditions, including grinding in an aqueous environment for at least 20 min, were established. A nanosized mesoporous single-phase HA powder with an average particle size of 20±2 nm, a pore size of 12 nm, and a pore volume of up to 0.29±0.01 cm3 / g was obtained.

Stationary and pulsed X-ray luminescence of nanocompositions based on polystyrene and inorganic scintillators (lanthanum bromide doped with cerium LaBr3(Ce) and caesium iodide doped with thallium CsI(Tl) has been studied. The formation of high-speed nanosecond illumination pulses with repeatedly enhanced intensity was detected. With certain combinations of the composition and the cooking mode, a concentration of the main radiation in a fast nanosecond component with high light output is achieved. This is explained by the formation of molecular cluster compositions, where the interaction of electronic and vibrational states of organic and inorganic components initiates a new shock-vibrational excitation mechanism.

The study aims at developing new injectable paste-like materials based on dicalcium phosphate dihydrate for minimally invasive replacement and defect bone replenishment in maxillofacial surgery and dentistry. The features of obtaining hydrated pastes on the base of dicalcium phosphate dihydrate was identified, the process parameters for synthesis were established, and the chemical and structural characteristics were studied. Experiments were conducted to evaluate the cytotoxicity of the developed hydrated pastes in vitro, and patterns in the effect of paste particle concentrations on the pH of the culture medium were revealed.

The dependences of the properties of polyurethane urea elastomers synthesized on the basis of oligotetramethyleneoxide diol and oligodiethylene adipate diol on the ratios between the components of the compositions were studied. It was found that the use of hardening mixtures based on oligoesters in compositions based on oligoethers allowed to obtain polyurethane urea elastomers with high hardness and excellent physical and mechanical characteristics. The limits of the temperature range of operation of the studied elastomers were discussed.

Представлены результаты исследования влияния термообработки твердого сплава WC-9%Co наносекундными импульсами ультрафиолетового лазера на структурные изменения и элементный состав его поверхности. Показана модификация структуры поверхности карбида вольфрама, в частности, формирование отдельных кластеров при энергии до 2 Дж / см2, что может влиять на механические свойства материала. Элементный анализ показал перераспределение Cr, Co и W, что, предположительно, связано с диффузионными процессами и образованием новых фаз соединений в приповерхностном слое.

This work investigated the adhesion performance of recycled concrete with nano-SiO2 and nano-Al2O3 and steel bars in cold environments through freeze‒thaw cycle tests and tensile tests. The results show that the nanomaterials and number of freeze-thaw cycles have no significant effect on the damage morphology of the sample, but the adhesion strength and steel bar slip of the sample are considerably affected by the nanomaterials and number of freeze-thaw cycles. After the addition of the nanomaterials, the adhesion strength increased by 10.4 % (11.2 %), and the steel slip increased, by 17.3 % (16.8 %). The impact of freeze-thaw cycles on adhesion strength and adhesion slip is significant. The adhesion strength decreases by up to 40.8 % after 55 freeze-thaw cycles, and the slip of the steel bar increases by up to 101.9 %. In addition, an adhesion performance model of recycled concrete and steel bars mixed with nanomaterials in cold environments is established. The strengthening mechanism of nanomaterials and the mechanism of freeze-thaw damage is revealed. This study provides a basis for the practical application of recycled concrete technology and promotes the recyclable use of building materials.

Due to high production costs, the production of activated carbon from waste has attracted a lot of attention recently. In this study, gelidium corneum (GC) was carbonized at 800 °C for 90 min. Its carbonization yield, adsorption capacity, and physical and chemical properties were investigated. Ultraviolet-visible spectroscopy (UV), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), proximate analysis and ultimate analysis were performed. According to XRD analysis, the structure of GC is semi-crystalline, but the crystalline structure increases after carbonization. The carbonization yield of GC was about 39%. According to SEM, UV and XRD analysis, the carbonization process supported crystallinity and the formation of micropore/mesopore structures. The crystal violet (CV) removal and adsorption capacity were 96 % and 9.63 mg/g at an initial dye concentration of 50 mg/L, 30 °C, adsorbent dosage of 5 g/L, constant stirring speed of 200 rpm and equilibration time of 60 min, respectively. The carbonized gelidium corneum (cGC) can be used as a suitable adsorbent for the removal of dyes from aqueous solutions. It can also be an alternative product to commercial products because of its high adsorption capacity and cost-effectiveness.