Advanced Materials Research Vol. 880

Abstract: The possibility of using epoxidized petroleum resins for modification of bitumen was shown. The dependence of the properties of coatings based on polymeric-bitumen compositions of the number of modifiers, hardening agent and the curing temperature was investigated. The optimum process parameters for polymeric-bitumen compositions were identified. The resistance of the coatings to different environments was investigated.

Abstract: The mathematical formulation of space-time energy release function of accelerated ions in solids is presented. High-power pulsed ion beam and continuous focused ion beam interaction with metals are considered. The power density of deposited energy and specific energy input in a target have been calculated. A beam energy fraction expended on the collisional sputtering of target atoms has been estimated.

Abstract: The paper presents the experimental results for the spectra of the luminescence burst and induced optical transient absorption in YLiF₄ crystals when exposed to the electron pulse of nanosecond duration over a wide temperature range. The luminescence spectrum consists of two bands with peaks at 4.4 and 3.2 eV, and in the spectrum of induced absorption the main bands are found at 2.1 and 3.7 eV. The luminescence at 3.2 eV decays faster than the bandwidth at 4.4 eV. The luminescence intensity decreases sharply at temperatures above 30 K. The induced absorption decreases at temperatures above 60 K. It is assumed that the kinetic curves of luminescence burst and transient absorption in excitation by radiation fluxes are related.

Abstract: The paper describes a new colorimetric sensor. The colorimetric sensors were made of optically transparent polymethacrylate matrix with physically immobilized analytical reagent which is responsible for the extraction of the analyte into the sensing material and changing its color. The developed colorimetric sensor can be used in determination of various analytes using both solid-phase spectrophotometer and naked eye.

Abstract: The main results of thermodynamic analysis and mathematical simulation of the deactivation of a platinum dehydrogenation catalyst by coke-generating compounds are presented. Developed model allows calculating the optimal flow rate of water fed to the reactor to maintain the conditions of thermodynamic equilibrium of the coke formation reaction and oxidation of intermediate condensation products with water. A comparative evaluation of different raw cycles of platinum-dehydrogenation catalysts is presented and shown to cause reduced production of the desired product was the change the composition of the feedstock.

Abstract: The paper represents the results of research related to the application of urea and glyoxal condensation product to modify the urea-formaldehyde resins (UF resins) aiming to obtain low-toxicity wood plates on the basis thereof. It was stated that the bicyclic polyfunctional compound is an effective modifier which not only does allow reducing the toxicity of wood-composite materials based on UF resins, but also increasing their physical-mechanical characteristics.

Abstract: Carbon nitride (CNx) powders were synthesized in the high-speed carbon electric discharge plasma jet flowing into the chamber filled with the nitrogen atmosphere at normal conditions. A coaxial magnetoplasma accelerator (CMPA) was used to generate the plasma flow. The CMPA was supplied from the pulse capacitive energy storage. Effect of input to the CMPA energy value on powders was studied by using several analytical methods (XRD, TEM, XPS). According to XRD with the increasing of input energy value the content of CNx in the product increased about 1.5 times. Its in a good accordance with the XPS data according to which the presence of nitrogen increased from 0.5 to 1.4 mass percent. Furthermore, the particles morphology was noticeable changed with the energy increasing. The obtained results revealed that by changing the energy parameters of the capacity energy storage its possible to influence on the product synthesized in the carbon-nitrogen system.

Abstract: The effect of interstitial hydrogen atoms on the mechanical properties and plastic strain localization patterns in tensile tested specimens of austenitic stainless and low-carbon steels have been studied using a double exposure speckle photography technique. The main parameters of plastic flow localization at various stages of the deformation hardening have been determined in steels electrolytically saturated with hydrogen in a three electrode electrochemical cell at a controlled constant cathode potential.

Abstract: Three different zeolites (erionite, mordenite and natural clinoptilolite) were used to study influence of zeolite topology on the state of copper during ion-exchange and following reduction in hydrogen flow. This comparative study clearly demonstrates the influence of used zeolite matrices on the process of implantation of copper nanospecies. Starting from the ion-exchange, the alterations in the state of Cu²⁺ ions start to be evident due to variations of the intensity of charge transfer band. Copper ions start to reduce at specific temperatures depending on the type of zeolite matrix. Copper plasma resonance band change its shape and position for different zeolites. In the case of Cu-CLI samples this band change both the shape and position for different temperature of reduction. These observations permit to suggest that the mechanism of copper ion reduction and agglomeration to form copper nanoparticles noticeably depend on the type of zeolite matrix. This mechanism is more complex for the Cu CLI than for the Cu-MOR and Cu-ERI systems. Copper nanoparticles formed at low temperatures in the case of Cu-CLI samples undergo changes while temperature of reduction grow.