При описании полицентровой ионно-координационной полимеризации изопрена на каталитической системе GdCl3 × n(i-C3Н7OH)‒Al(i-C4H9)3 решена обратная кинетическая задача для схемы процесса с медленным инициированием. Задачу определения числа активных центров полимеризации решали путем деконволюции экспериментальных ММР суперпозицией распределений Флори. Найдено, что в полимеризации участвует четыре типа активных центров, кинетическое различие которых в процессе формирования фракций полимера с характерными для них средними молекулярными массами и наиболее вероятным ММР обусловлено их различием в концентрациях предреакционных каталитических центров и константах скоростей протекающих на них реакций. Для каждого типа активных центров определены парциальные конверсии расходования мономера, константы скоростей инициирования, роста цепей и передачи на мономер.

In the description of multicenter ion-coordination polymerization of isoprene on the catalytic system GdCl3· n(i-C3Н7OH)‒Al(i-C4H9)3 the inverse kinetic task for the scheme of a process with slow initiation has been solved. The task of determining the number of active centers of polymerization was solved by deconvolution of experimental MWDs through superposition of Flory distributions. It has been shown that four types of active centers participate in polymerization, the kinetic difference of which in the process of formation of polymer fractions with their characteristic average molecular weights and the most probable MWD, is associated with their difference in the concentrations of pre-reaction catalytic centers and the rate constants of reactions occurring on them. For each type of active centers, partial conversions of monomer consumption and rate constants of initiation, chain propagation, and chain transfer to the monomer are determined.

Lanthanide catalysts are used in the industrial production of stereoregular rubbers. It is believed that the activity of solvate complexes of lanthanide chlorides increases with decreasing size of their particles and increasing content of the solvating ligand. The kinetics of isoprene polymerization catalyzed by the isopropanol solvates of gadolinium chloride GdCl 3 · n ( i -PrOH), which were obtained by various methods (conventional mechanical stirring, hydrodynamic exposure, ultrasonic irradiation), was studied. A correlation between the particle size and composition of the solvate complex and the activity of the catalyst was found whatever the method the solvate complex was obtained. At the same time, the resulting data show that, at comparable particle size and composition of the complex, its activity in the polymerization of isoprene nevertheless depends on the method of synthesis. It was shown that the gadolinium catalysts exhibit the highest activity in isoprene polymerization, when the solvate complexes are subjected to hydrodynamic treatment after preliminary solvation for 4–8 h.

The kinetics was studied for the polymerization of isoprene under the action of a catalyst based on an isopropanol solvate of gadolinium chloride and triisobutylaluminum (TIBA). It was shown that this catalyst is less active in the polymerization of isoprene than a similarly synthesized neodymium catalyst, and the kinetic curves for the yield of polyisoprene are S-shaped. It was found that the low activity of the catalytic systems based on the isopropanol solvate of gadolinium chloride is caused by the extremely low rate constant for the incorporation of the first monomer molecule. The inverse problem of determining the kinetic parameters of elementary step was solved, and the rate constants of the chain initiation and propagation reactions and the initial concentration of pre-reaction centers were determined. It was demonstrated that the model curves fit the experimental conversion curves with a high correlation coefficient.

The prototype of a magnetic locator based on a magnetoresistive compass is designed and studied. The effectiveness of the modified algorithm and software for calculating spatial and angular coordinates of a magnetic dipole and the electronic part of a prototype magnetic capsule is shown. Software for data processing and 3D visualization of the trajectory of magnetic dipole motion is developed. It is shown the software can be used in a computer-aided design system (CADS).

Kinetic features are studied of the chemisorption and reduction of molecular oxygen from water by metal–ion exchanger nanocomposites that differ in the nature of the dispersed metal and state of oxidation. In the Pd < Ag < Cu series, the increasing chemical activity of metal nanoparticles raises the degree of oxygen sorption due to its chemisorption and subsequent reduction, while the role of the molecular chemisorption stage increases in the Cu < Ag < Pd series. Metal particles or their oxides are shown to act as adsorption sites on the surface and in the pores of the ion-exchanger matrix; the equilibrium sorption coefficient for oxygen dissolved in water ranges from 20 to 50, depending on the nature and oxidation state of the metal component.

Методом химического осаждения синтезированы новые нанокомпозиты медь-сульфокатионообменная матрица Lewatit SP-112 H и Lewatit K 2620. Полученные материалы отличаются изопористой структурой и монодисперсным распределением частиц меди по размеру. В химическом отношении синтезированные нанокомпозиты показывают более высокие скорости поглощения кислорода при однократном осаждении меди и практически одинаковые параметры при пятикратном осаждении, а также характеризуются большей воспроизводимостью кинетических данных по сравнению с аналогом КУ-23, что позволяет отнести их к высокоэффективным нанокомпозитным материалам для глубокого удаления молекулярного кислорода из воды

Results are presented from research on developing a theory and model of magnetic location based on a set of manufactured magnetoresistive compasses. The working capacity of the developed algorithms and software for calculating the spatial and angular coordinates of a magnetic dipole, the electronic part of the magnetic location model, and the software for processing and visualizing data are described.

The disperse composition of trans-1,4-polyisoprene granules and supported titatium–magnesium catalyst particles in the ultrarapid polymerization of isoprene within 0.1–0.7 s is studied. It is shown that within this period the alteration of external and internal fragmentations occurs between two fractions of polymer granules that are formed by 0.1 s of polymerization and already contain significantly fragmented catalyst particles. The correlation between these processes and molecular mass characteristics of trans-1,4-polyisoprene is investigated. It is found that the external fragmentation is accompanied by a decrease in the average molecular masses of the polymer, while the internal fragmentation leads to formation of a higher molecular mass trans-1,4-polyisoprene. As a result, the fraction of polymer granules with a diameter of 7.5 μm is formed by 0.7 s of polymerization and replication to high conversions is developed on their basis.

We show the results of our studies related to control over objects by the magnetic field they generate. We propose a model to compute the current and its magnetic field in a conductor with a rectangular defect. We describe the developed and produced anisotropic magnetoresistive gradiometer head to measure surface magnetic fields in order to control the functionality of electronic components by the magnetic field they generate. We describe the operation of a testbed with a test circuit in the plotter.

Рассмотрены результаты исследований возможностей контроля изделий по создаваемому ими магнитному полю. Предложена модель расчета тока и создаваемого им магнитного поля в проводнике с прямоугольным дефектом. Описана разработанная и изготовленная анизотропная магниторезистивная головка-градиометр для измерения приповерхностных магнитных полей для контроля функционирования электронных компонент по создаваемому ими магнитному полю. Описана работа стенда с тестовой платой в составе плоттера.

New type of anisotropic magneto-resistive transducer of magnetic field representing magnetic field gradiometer with even volt-oersted characteristic saturated with magnetic field increase, is considered. Results of its development are given as magneto-sensitive nanoelement for biosensor and magnetic head.

Anisotropic magnetoresistive magnetic field sensor with an odd-function symmetry output characteristic is developed for use in magnetic field analysis microsystems. Prototypes of magnetic field sensor with maximal sensitivity about 0,7 mV/V/Oe are fabricated and characterised.

Magnetic properties of nanoscale magnetic-layer systems using FeNi, Co, FeMn, Al2O3, and SiC layers are studied experimentally. The dependence of magnetic behavior on the system geometry and parameters is addressed. Ferromagnet-semiconductor exchange coupling subject to the amplitude of an applied magnetic field is revealed. It is found that the magnetic behavior of the nanostructures varies in a nonlinear manner with applied magnetic field. Spin-tunneling magnetoresistance is observed in magnetic-layer junctions containing an Al2O3 spacer. In-plane-conduction magnetic-field sensors using an Al2O3 or a SiC spacer are fabricated and tested.

The magnetic and magnetooptical properties of spin-tunneling multilayer permalloy-silicon carbide nanoheterostructures deposited by rf sputtering have been studied. Magnetometric and magnetooptical methods are used to show that the magnetic-semiconducting nanostructures have a complex magnetic structure and to track the evolution of the magnetic properties of these structures as functions of the magnetizing field and the thickness and sequence order of ferromagnetic and semiconducting layers in them. The induction response and the field and orientation dependences of the transversal Kerr effect are found to have anomalies. The experimental results are interpreted under the assumption that there is exchange interaction between the ferromagnetic and semiconducting layers through a thin magnetically ordered transition layer formed inside the interface.