Physical and mathematical model of the control system parameters of the optical signal using the sensor of the external action on the basis of a diffraction grating with variable characteristics (the lattice period; the width of the transparent strip (zone); width of the absorbing strip (zone)) are developing. A mathematical model of the diffraction grating is constructed on the basis of equations to calculate the resulting intensity and amplitude of the interference light passing through the grating. For the model of a lattice with a round hole, equations containing special functions of the Bessel function type, calculated numerically by calculating convergent infinite power series and integrals which are not calculated analytically, are proposed. The degree of accuracy of the developed model is determined by the severity of the underlying fundamental equations of theoretical and mathematical physics.

Metal-polymer composites based on copolymers of polypropylene glycol maleate phthalate with acrylic acid and metallic nickel and silver were synthesized for the first time. The objects obtained were characterized by infrared (IR) and Raman spectroscopies, thermogravimetry, a scanning electron microscope with energy dispersive spectroscopy, and atomic emission spectrometry. The catalytic activity of new metal-polymer composites that exhibited a rather high efficiency in the reactions of electrocatalytic hydrogenation of pyridine was studied. It is shown that nanoparticles of metals are evenly distributed in the volume of the polymer matrix; more than 80% of nanoparticles are in the range from 25 to 40 nm and have spherical and rhombic shapes. The reusability of the obtained composites is shown.

Previously unknown amidophosphorous acid derivatives were prepared by transamidation of tert-butyl N,N-diethyl-N′-(4-phenylthiazolyl)phosphorodiamidite with 2-amino-4-phenylthiazole, and their reactions with acetyl and benzoyl chloride were studied. These reactions are shown to proceed regioselectively according to the Arbuzov scheme to give the corresponding ketophosphonates. The reaction of the phosphorodiamidite with acetyl chloride in a 1:2 molar ratio involves formation of acetophosphonate that reacts in the enol form to give the corresponding (1-acetoxy)vinylphosphonate.

For the first time, the kinetics of isothermal curing and thermal degradation of polyethylene glycol maleate (pEGM)–based systems and their composites with mineral fillers were investigated in the presence of a benzoyl peroxide/N,N-Dimethylaniline redox-initiating system. DSC analysis revealed that the curing process at 20 °C can be described by the modified Kamal autocatalytic model; the critical degree of conversion (α_c) decreases with increasing content of the unsaturated polyester pEGM and in the presence of fillers. In particular, for unfilled systems, α_c was 0.77 for pEGM45 and 0.60 for pEGM60. TGA results demonstrated that higher pEGM content and the incorporation of fillers lead to increased thermal stability and residual mass, along with a reduction in the maximum decomposition rate (dTGₘₐₓ). Calculations using the Kissinger–Akahira–Sunose and Friedman methods also confirmed an increase in the activation energy of thermal degradation (E_a): E_KAS was 419 kJ/mol for pEGM45 and 470 kJ/mol for pEGM60, with the highest values observed for pEGM60 systems with fillers (496 kJ/mol for SiO₂ and 514 kJ/mol for CaCO₃). Rheological studies employing three-interval thixotropy tests revealed the onset of thixotropic behavior upon filler addition and an increase in structure recovery after deformation of up to 56%. These findings underscore the potential of pEGM-based systems for low-temperature curing and for the design of composite materials with improved thermal resistance.

В статье рассматриваются электронно-микроскопические и термохимические свойства клатратных композиций β-олигосахаридных комплексов включений алкалоида цитизина и его диметилфосфатного производного, функционализированные наночастицами серебра. Для визуализации и анализа эволюции их структуры при различных температурных режимах на сканирующем электронном микроскопе проведены морфологические исследования полученных нанокомпозиций частиц. Методами термогравиметрического и дифференциального термогравиметрического анализов получены данные кинетики термического разложения изучаемых субстратов, а также их инкапсулированных комплексов включений - цитизина и его производных с наносеребром. Результаты исследований позволили выявить соответствующие фазовые превращения нанокомпозиций, а также возможные процессы рекристаллизации и другие изменения, происходящие в комплексах включений в результате отжига. Полученные энергетические профили, воспроизведенные различными аналитическими и расчетными методами (непараметрической кинетики и методом Фридмана), показали, что процессы разрушения молекул клатратов под воздействием тепла начинаются с реакций с более высокими значениями энергии активации (Ea) и продолжается с равномерным уменьшением Ea, что свидетельствует о многостадийности процесса. Полученные кинетические данные способствуют прогнозированию свойств полученных композиций клатратных комплексов цитизина и его фосфорпроизводного, а также поиску оптимальных путей их стабилизации в условиях длительного хранения.