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Composite materials based on gold nanoparticles electrochemically deposited on a carbon substrate of functionalized graphene oxide, reduced graphene oxide, and carbon nanotube paper in the cyclic voltammetry and chronoamperometry mode are proposed. Screening of composite materials by atomic force microscopy, electrochemical impedance spectroscopy, and voltammetry made it possible to select the best ones as modifiers of planar electrodes, on the basis of which highly sensitive immunosensors are developed. For the best amperometric immunosensors based on a combination of carbon paper, amino(thia)calix[4]arene, and gold nanoparticles, the range of working concentrations for the determination of amitriptyline and desipramine is 1 × 10 –9 –1 × 10 –4 M, the limit of quantification is (4–6) × 10 –10 M. Amitriptyline and desipramine are determined by amperometric immunosensors in pharmaceutical preparations with the relative standard deviation no more than 4%. A Comparison of the results of the determination of tricyclic antidepressants in human urine by immunosensors and fluorescence polarization immunoassay with a relative standard deviation no more than 8.5% indicates the accuracy and repeatability of the results obtained.

New experimental thermodynamically consistent data are presented on the temperature dependence of thermal diffusivity, heat capacity, and thermal conductivity (λ = a ρ C p ) of black coal calculated on their basis. The effect of the thermal decomposition (pyrolysis) of coal near 700 K and evaporation of moisture and other easily volatile components of coal at 380 K on the behavior of heat capacity and thermal conductivity was studied experimentally. The measurements were carried out using the contact-free laser flash (Netzsch LFA 457) method in the temperature range 301–823 K. Based on the measured values of the thermal diffusivity of black coal, the heat transfer process in a coal bed was studied. It is shown that taking into account the temperature dependence of the thermal diffusivity of the medium when solving the heat transfer equation significantly affects the temperature distribution in the coal bed.

Nonlinear optimal mobile control of thermal processes in a mixed inverse problem for a Barenblatt–Zheltov–Kochina differential eauation with a Hilfer fractional operator is studied. The inverse problem is considered with spectral and final conditions. The necessary optimality conditions for nonlinear mobile control are formulated. The determination of the optimal control function is reduced to solve system of Fredholm functional-integral equations, which consists product of two integrals of nonlinear functions. The unique solvability of this nonlinear functional-integral equation is proved by the method of contracting mapping. Approximate calculations for the state function of the controlled process, for the redefinition function, and for the optimal control function are obtained. The absolute and uniform convergence of the obtained Fourier series are proved.

Histochemical Analysis of Medicinal Plants and Raw Materials is a method aimed at studying the localization of chemical substances and their metabolic products in plant tissues. This article presents the results of the histochemical analysis of the leaves and petioles of \"Fragaria viridis\" and \"Fragaria vesca\". The genus \"Fragaria\" belongs to the Rosaceae family, and includes several species known for their high content of biologically active compounds, including phenolic compounds, flavonoids, and lipids. These substances contribute to the medicinal properties of strawberries, making them valuable both in traditional medicine and modern pharmacology. Objective: To determine the characteristics of the localization of specific groups of secondary metabolites in the aerial parts of \"Fragaria viridis\" and \"Fragaria vesca\" growing in the Central Kazakhstan region at the microscopic level. Materials and Methods: Transverse sections of the leaves and petioles of F.viridis and F.vesca were fixed in Strauss-Fleming solution, after which histochemical reactions were performed to determine the location and identify essentialoils, phenolic acids, flavonoids, sesquiterpene lactones, polysaccharides, and alkaloids. The study of microscopic features and histochemical tests was conducted according to the methods of the State Pharmacopoeia of the Republic of Kazakhstan using a Biomed-4 light microscope. Results: Histochemical methods using light microscopy were employed to determine the localization of biologically active substances in the studied plant raw material. The presence of phenolic acids, flavonoids, and essential oils was detected. The absence of sesquiterpene lactones, polysaccharides, and alkaloids in the examined material was established. Conclusion: For the first time, histochemical tests were used to study the localization of secondary metabolites in the tissues of \"F. viridis\" and \"F. vesca\". The results of these histochemical studies can be utilized for confirming authenticity, identification, and standardization of the aerial parts of \"F. viridis\" and \"F. vesca\".

Histochemical analysis of medicinal plants and raw materials is necessary to study the localization of various chemical substances and their metabolic products in plant tissues. The article presents the results of histochemical analysis of leaves, flowers, stems, fruits, and roots of Ferula songarica. Since ancient times, Ferula has been used in folk medicine by native people of Central Asia, Iran, China, India, etc. to treat various diseases. Aim. Identifying the localization of specific individual secondary metabolites in plant tissues of the aerial and underground parts of Ferula songarica grown in the Karaganda region. Materials and methods. Ferula songarica raw material samples were placed in Strauss-Fleming solution; the tissue cross-sections were sliced manually with a razor blade Histochemical reactions were carried out to detect and to identify essential oils, starch, phenolic acids, flavonoids, sesquiterpene lactones, polysaccharides, and alkaloids. The methods of the State Pharmacopoeia of the Republic of Kazakhstan allowed revealing the localization of biologically active substances. Micropreparations were viewed with a Biomed-4 microscope and photographed with the Altamy Studio Program. Results. Light microscopic histochemistry allowed determining the localization of biologically active substances in the studied plant raw materials. The presence of phenolic acids, flavonoids, sesquiterpene lactones, polysaccharides, alkaloids, and essential oils as well as the absence of starch were established. Conclusion. For the first time, the histochemical tests were applied to examine the localization of Ferula songarica tissues’ secondary metabolites. The results of the histochemical research can be used to authenticate, identify, and standardize the aerial and underground parts of Ferula songarica.

A method for the determination of amitriptyline, a tricyclic antidepressant, in human urine by immunosensors has been developed using supramolecular systems based on hexamolybdenum cluster complexes. These complexes have electrochemical activity and give a stable analytical signal, which was used in the development of amperometric immunosensors. Luminescence and dynamic light scattering methods were used to demonstrate the formation of a supramolecular system of self-organized hexamolybdenum nanoparticles and chitosan molecules. A composite material based on hexamolybdenum cluster complexes in combination with reduced graphene oxide has been developed. The working range of amitriptyline concentrations to be determined by an amperometric immunosensor was 1 × 10 –9 –1 × 10 –4 M, the limit of determination was at a level of 5 × 10 –10 M, and the amitriptyline content of urine samples was at a level of ( n – 7) × 10 –8 M. A comparison of the results of analysis performed using an amperometric immunosensor and a fluorescence polarization immunoassay showed the absence of significant systematic errors. The ability to determine amitriptyline in biological fluids makes it possible to select an optimal therapeutic dose of the drug, that is, to develop approaches to creating personalized medicine.

The research was conducted to study genetic intervarietal and intravarietal polymorphism for identification and certification of soybeans using microsatellite markers. Genotyping of ten soybean varieties—Lira, Barguzin, Sayana, Lyubava, Rys, Slavia, Irbis, Triada, Vita, and Chara—bred at the V.S. Pustovoit All-Russian Research Institute of Oil Crops was performed using 13 microsatellite markers; 47 plants of each variety were analyzed. The presence of intravarietal polymorphism was revealed in all varieties. The proportion of polymorphic loci varied from 7.69% in Lira to 92.31% in Chara. The average number of detected and effective alleles for all varieties was 1.68 and 1.12, respectively, the observed and expected heterozygosity was 0.006 and 0.076, and the Shannon information index was 0.14. The studied soybean varieties turned out to be populations consisting of several biotypes with different frequencies of occurrence. Genotyping by 13 microsatellite markers made it possible to distinguish eight of ten analyzed soybean varieties. Two varieties that did not differ from each other and originated from the same hybrid combination (Barguzin and Sayana) had two biotypes each. Each biotype of one variety had a similar allelic composition to the biotype of the other at 13 and 12 microsatellite loci, respectively. As a result of discriminant analysis of the principal components of alleles of microsatellite loci, 470 soybean plants were distributed into nine clusters. Most of the plants were combined into unique clusters corresponding to their varieties despite the presence of intravarietal polymorphism. Isolation of different biotypes from existing varieties using DNA markers and their subsequent evaluation can be the beginning of breeding work to create new soybean varieties.

We have studied the chemical composition of the essential oil of Ferula songarica and the antifungal activity of the underground part of Ferula songarica growing in the vicinity of Karkaralinsk, Karaganda region. It was revealed that the main components of this oil are pinene - 32.91% and 3-octene-5-ene-2,7-dimethyl-, (E)-19.47%. As a result of a study on antifungal activity, it was found that Ferula songarica essential oil and gel based on Ferula songarica essential oil have a pronounced antifungal effect against clinical strains of yeast fungi C. albicans, C. dubliniensis and C. glabrata. The article presents the results of the development of the composition and technology of an antifungal gel based on the essential oil of Ferula songarica, growing in Central Kazakhstan. Research has been conducted to select the optimal gel base to ensure the stability and therapeutic effectiveness of the drug. The optimal formulation parameters, including the concentration of essential oil (3%), were experimentally determined, and its high antifungal activity against strains of the yeast fungi C. albicans, C. dubliniensis and C. glabrata was confirmed. The rheological properties of the gel have been investigated, and the characteristics that ensure the convenience of application and restoration of the structure after mechanical action have been identified. The developed gel production technology ensures the stability of physico-chemical properties and microbiological purity throughout the shelf life.

Here we present the results of an experimental study of the temperature and pressure dependences of the heat conductivity of composite compounds. The thermal conductivity of sandstone was measured by the absolute stationary method for pressures up to 400 MPa in the temperature range 273-523 K. From these experimental data we have proposed the equation describing the dependence of the thermal conductivity from the pressure and temperature. We have found that under the action of hydrostatic pressure the intensive growth of the heat-conductivity of gas-saturated sandstone is mainly up to 100 MPa, and then seamlessly switches to saturation. A comparative analysis is carried out with the experimental dependences of the thermal conductivity of ceramics (lanthanum sulfide LaS1.48).

A model for the structure of a rock as a heterogeneous system of two components, amorphous and crystalline, is considered. A formula is proposed for calculating the thermal conductivity of rocks with different temperature dependences of the thermal conductivity of their components. When the temperature dependence of the thermal conductivity of the components and their volume fractions is known, the thermal conductivity of the actual rock can be predicted for different combinations of amorphous and crystalline phases.