Abnormal changes have been found in the viscosity of aqueous poly(vinyl alcohol) solutions with different concentrations (1–8%) exposed to UV irradiation for 0–60 min. A molecular mechanism of this phenomenon has been proposed based on the assumption of a rearrangement in the hydration shells of the functional groups of poly(vinyl alcohol) as a result of changes in the environment under the influence of UV irradiation.

Al–Cu mixtures of various compositions underwent the plastic deformation under pressures from 0.5 to 4.0 GPa at room temperature on a Bridgman-anvil-type high-pressure apparatus. The influence of treatment pressure on calorimetric properties of Al and Cu powder mixtures of various compositions is studied. The thermal processes in the samples after deformation under pressure were studied with DSC and TGA within 20–800°C, whereas the structure and composition of the samples and its changes during heating were analyzed with the electron-microscopy method coupled with an energy-dispersive X-ray probe. A positron-annihilation method was used to study the atomic-electronic structure of deformed mixtures. The deformed mixtures were tested electrochemically at room temperature in a 6 M KOH solution. The results obtained indicate that the changes in the electronic subsystem of the mixtures can make a significant contribution to the heat release of the samples that underwent plastic deformation under high pressure.

Liquid aqueous systems of ethylenediamine (ED) and 1,3-diaminopropane (3DP) of various concentrations are studied via dynamic light scattering at 15 and 25°C. Dispersed phases are found in both systems. Their formation is explained by the presence of rather stable aqua complexes and protonated forms of diamines in aqueous solutions. The strong interaction between diamines and water is confirmed by a strong negative enthalpy of mixing and a substantial increase in the viscosity of aqueous solutions upon raising the concentration of diamine up to the formation of ED⋅ n H 2 O and 3DP⋅ n H 2 O associates.

The effect of the surface of an untreated and annealed copper substrate on the dissipative α-relaxation process in a highly elastic acrylic polymer is analyzed. The analysis is based on a comparison of the structural state and elemental composition of the metal surface, which are studied using physicochemical methods, with the intensity of internal-friction peaks, the glass-transition temperature, and the elasticity of the copolymer. The characteristics of the surface layer are correlated with the elastic properties of the polymer.

Various stages of crystallization of the dipeptide potassium salt on graphite and gold. Possible molecular structures of the dipeptide (a) and its potassium salt (b).

The kinetics of optical properties is studied experimentally on an OT Aerosol (dioctyl sulfosuccinate sodium salt)/isooctane/Qr (quercetin)/Ag+) reverse micellar system (RMS) during the chemical synthesis of Ag nanoparticles. The kinetic light optical absorption data acquired for an RMS at a wavelength λ = 432 nm with a chronometric resolution of 0.14 and 1 s are used to calculate the boundaries of the stages of Ag NP formation (at a confidence factor of at least 0.99). The determination of relaxation times (almost-periods) in an RMS allows evaluation of the kinetics parameters at certain stages of the chemical synthesis of NP metals.

A comparative analysis has been performed for the structure of ring deposits resulting from the evaporation of droplets of aqueous dispersions of gold nanorods and composite nanoparticles with a gold core/organosilica shell structure based thereon. The nature of the particles has been shown to have a key effect on the character of their packing near a three-phase contact line. The study of the conductivity of the ring deposits obtained from dispersions of the composite particles has shown that it is realized via over-barrier electron emission.

This study reports the formation, structure, geometric characteristics, and conductivity of composite thin films obtained via the mobile meniscus method from nanodispersed silver particles with diameter less than 10 nm. The film thickness and the conductivity as functions of the weight concentration of a precursor (AgNO3), silver nanoparticle concentration (size), and evaporation temperature are established as well.

Pulsed (square-wave) electrodeposition of platinum nanocrystallites with a high concentration of (100) regions from a H2PtCl6 solution with different background anions is studied. The effect of the background electrolyte is shown, namely, a more perfect cubic faceting of crystallites obtained in the 0.1 M HClO4 solution as compared to 0.5 M H2SO4. A procedure for deposit formation (secondary growth) with intermediate pulsed treatment in acid is suggested that does not involve application of high negative/positive overpotentials (no additional increasing of the mobility of platinum atoms). This allows preserving the crystallite structure and improving the overall deposit structure. In addition to conventional methods of fine surface structure determination on the basis of the hydrogen UOregion in cyclic voltammograms in sulfuric acid and SEM, we propose analysis of the Pt(100) terrace concentration/width based on the characteristic peak of nitrate ion reduction in voltammograms in perchloric acid. Stepped Pt single crystals with (100) terraces of different width are used for comparison. The effect of solution temperature on formation of faceted crystallites is shown and the optimum deposition temperature is determined: the optimum temperature in perchloric acid solution is 40 degrees C, while an increase in the temperature in sulfuric acid solutions results under the chosen conditions in deposition acceleration and an increase in the amount of surface defects.

The morphology and composition of an oxide layer on the surface of iron chipping cuts obtained using metal-working under conditions of intense plastic shear deformation and subsequent thermal oxidation have been investigated by scanning electron microscopy with an X-ray probe, Raman spectroscopy, and thermogravimetry. It is shown that agglomerations of metal–oxide nanoparticles and nanostructures (whiskers, nanotips, and nanoleaves), which are promising for production of new composites with ultra-fine-grained metal–oxide filler, are formed with a high rate on the surface of metal chippings during annealing in air at 800°C. The economic and ecological benefits due to recycling of metalworking wastes for producing new metal–oxide nanomaterials and related composites appear to be significant.

The effect of pulse neutron gamma-radiation on material made from sintered ceramics of hexagonal boron nitride α-BN is studied using positron annihilation spectroscopy (PAS). The radiation vacancy defects of the α-BN crystal lattice are effective traps of the positrons diffusing into the bulk particles of the material. The positrons’ lifetime (LT) spectra and angular correlation curves of annihilation gamma-ray quanta (ACAR) in ceramic specimens irradiated by neutrons with a cumulative dose of the neutron flow of 10 13 to 10 14 neutron/cm 2 (the average energy of the neutrons is 1.7 MeV) and gamma radiation of 10 3 to 10 5 Р ( E γ = 1 MeV) with the subsequent annealing of the irradiated specimens at 600°C are measured. The observed changes of the annihilation characteristics of the LT and ACAR in the irradiated and sintered specimens allow us to conclude that there is an effective capture of the alpha particles formed upon neutron irradiation via the nuclear reaction B 10 ( n , α)Li 7 with vacancy defects. Helium atoms are released from vacancies to the surface of the α-BN plates upon annealing of the irradiated specimens at 600°C. This mechanism explains the high level of radiation stability of α-BN ceramic dielectrics in ionizing radiation fields.

Alkyl (meth)acrylate polymers are synthesized by dispersion polymerization in aqueous media and modified by filling them with highly dispersed iron powder in order to investigate the possibility of enhancing physicomechanical properties of composite materials. The structure of prepared filled polymer materials is investigated and related to their highly elastic properties.

The effect of an increase in the intensity of light scattering from a deionized water sample in air over time in the UV region is revealed. The dependence of the intensity of UV radiation scattering from deionized water on the wavelength is also studied. The temperature dependence of the intensity of laser radiation scattering from deionized water at λ = 633 nm is determined.