| Nashriyot | Самарқанд давлат университети |
|---|---|
| Shahar | Samarqand |
| ISSN | 2091-5446 |
| e-ISSN | 2181-1296 |
| Tashkil etilgan | 1999 |
| Nashr tillari | O‘zbek |
| Maqolalar soni | 1381 |
| OAK holati | Ro‘yxatda |
In this paper, the problem of nonlinear random parametric oscillations of a vibration-protected mechanical system is considered. Nonlinear ambiguous functions characterizing the dissipative properties of materials of…
In this study, the effect of different solvent phases (water, DMSO, acetonitrile, ethanol, chloroform and heptane) on the electronic, reactivity and nonlinear optical (NLO) properties of paracetamol was analyzed using…
Pyrrolo[2,3-d]pyrimidinones were made by reacting tricyclic pyrrolo[2,3-d]pyrimidinones with 4-halogenated phenylamines. The structures of all the new compounds were figured out using ¹H-NMR, ¹³C-NMR analyses.
A green low-temperature method for the synthesis of nanostructured KPbBr₃ perovskite is presented. The obtained nanocrystals are integrated into a hydroxyethyl cellulose (HEC) matrix, at RH = 95% the photosignal…
This paper considers a mathematical model of the transport of a degrading solute in a two-zone porous medium, including active and passive zones. The model takes into account the processes of diffusion, adsorption and…
Currently, ion-selective electrodes are used to control the composition of process solutions in various industries, and to analyze ultrapure water. They have also found application in medicine, as they meet the…
The paper analyzes some parametrized singular surfaces in three dimensional Euclidean spaces. It is investigated a transversality condition for these surfaces.
This article analyzes the experience of developed and developing foreign countries in the territorial organization of urbanization processes. In particular, examples from countries such as the United States, Sweden…
This paper is devoted to study the mixed problem for a nonhomogeneous pseudoparabolic equation. The Hilfer fractional equation is studied with initial value conditions recording first variable t and Samarskii-Ionkin…
In this scientific paper, the landscape-meliorative approach and the evaluation of landscapes based on various principles are examined in the context of studying landscape complexes, with the Middle Zarafshan as a study.
Wеаkly intеrаcting cоmplеxеs оf CD₃Hаl···HCl (Hаl = F, Cl, Br) hаvе bееn invеstigаtеd in а liquid аrgоn еnvirоnmеnt using infrаrеd (IR) spеctrоscоpy аnd dеnsity functiоnаl thеоry (DFT) cаlculаtiоns. Thе structurаl аnd…
Initially, using the cyclization methods known to us, quinazolin-4-one derivatives containing bromine in the 6 position were synthesized and converted into 6-bromo-quinazolin 4-thiones using Lawesson's reagent. The…
This paper presents the results of obtaining a thin-film hybrid structure on the surface of a single-crystal silicon wafer with a fairly thin layer of silicon dioxide (SiO2) (~2÷4 nm), in which a thin perovskite layer…
In the present research note, we have derived the explicit expression for the perihelion precession and the deflection angle of light by the gravitational object. The explicit expression for the trajectory of the planet…
A novel series of 6-bromo-benzo[2,1 b]pyrimidin-4-thiones were synthesized. Thiones of the tricyclic pyrimidinones are obtained via a conversion procedure, where the C=O functional group is successfully converted into…
The effect of a mixed solvent of water - isopropanol was studied on the relative volume of polyvinyl alcohol gel in solutions of various electrolytes of different concentrations. Kinetic curves of the change in the…
In this work, the synthesis of iron ( Fe(II)), cobalt (Co(II)) and zinc (Zn(II)) ion complexes with flavonoids quercetin and rutin was studied and their stability constants at different pH values were estimated. The…
By periodate oxidation of inulin, samples of polyaldehydinulin with varying degrees of oxidation have been obtained. The obtained polyaldehydinulines were used for the chemical modification of the low molecular weight…
The structural, electronic, and bonding properties of hydrogen-bonded complexes between formamide and urea in different stoichiometric ratios (1:1, 1:2, and 2:1) have been investigated using Density Functional Theory…
In this work, interactions of glyoxal in ethyl alcohol, water and dimethylsulfoxide (DMSO) complexes and their spectral manifestations were studied using ab-initio calculations. The molecular forces, bond structure and…
It is known that the theorems of Desargues and Steiner are the main theorems of projective geometry. In all sources, the proofs of these theorems are given by axiomatic methods. Since the axiomatic method consists of…
This paper investigates the self-similar analysis of a system of equations given by a diffusion process. The study focuses on a coupled system of nonlinear parabolic partial differential equations (PDEs) that describe…
In this paper, the characteristic vibrational modes of aniline were analyzed using polarized Raman and two dimensional Raman correlation spectroscopy methods. Polarized Raman spectra revealed the presence of anomalous…
To study the chemical and mineralogical composition of the selected clays, montmorillonite clays from the Navbahor deposit (Navoi region) were studied in order to determine the degree of this sorbentity. The work used…
7H-Pyrrolo[2,3-d]pyrimidines or 7-deazapurines are analogs of purines, which are part of DNA and RNA found in the human body, and therefore exhibit a high level of biological activity. There are also several approved…
In this paper, we developed a method for synthesizing low-porosity silica gel modified with nanomagnetic material Fe3O4, and studied its textural and sorption characteristics. The resulting material was characterized by…
In this work, the effectiveness of various citric acid-based compositions for dissolving kidney stones consisting of calcium oxalate and phosphate was investigated. Experiments were conducted with different…
In this work, the influence of the ratio of stabilisers oleylamine and oleic acid on the optical and structural properties of perovskite KPbBr₃ has been studied. The luminescence, infrared spectroscopy and light…
This study explores the integral formulations and harmonic fundamental solutions for various media, including elastodynamic, scalar, and poroelastic media. Integral formulations are expressed in terms of boundary…
This paper presents the results of experiments on the technology of obtaining and studying the mechanisms of current transport in a p+––p+ (p+–p–p+) structure based on zinc compensated silicon in the dark and at…
We conducted a comprehensive investigation into the relationship between Forbush decreases (FDs), Geomagnetic storms (GS), and Coronal mass ejections (CMEs) during Solar cycles (SC) 23 and 24. GS characterized by the…
The synthesis of novel thieno[3,2-d]pyrimidine derivatives commenced with 5-bromo-2-chlorobenzonitrile with ethyl-2-mercaptoacetate, which yielded the compound AT-2. The addition of piperidin-2-one to the formed AT-2…
In this paper the Friedrichs model with rank three perturbation, acting in the Hilbert space is considered. This model is a linear, bounded, and self-adjoint and it is a model operator corresponding to the Hamiltonian…
This study investigates the physicochemical properties of nanocomposites based on CdSe/CdS/ZnS triplet quantum dots. Methods for their synthesis, including stepwise deposition of CdS and ZnS shells to improve optical…
Here, we demonstrate that the assembly of nanostructures with different dimensionalities yields “multicomponent hybrid” transparent conductive films (TCFs) with sheet resistance and optical transmittance comparable to…
To synthesize new derivatives of quinazolinones by the Buchwald-Hartwig method, 6-bromo-quinazolin-4-one derivatives were initially synthesized using cyclization methods and converted into 6-bromoquinazolin-4-thiones…
In this article, a system of logical equations is created using logical functions through methods of expressing the relationship between symptoms of diseases and the diseases themselves in the language of logical…
In this paper we consider the Cauchy problem for the n-order polyharmonic equation in an unbounded domain D, where boundary data are given on a part of boundary. The goal is to reconstruct a polyharmonic function u(y)…
In this work, the reaction of crotonaldehyde ethinylation was studied for the first time using complex catalytic systems prepared based on trifluoromethylsulfonate salts of some d-group metals. Aliphatic and aromatic…
The increase in the volume of information leads to an increase in the technologies and research for their processing. The study proposes a parallel implementation technology for matching records with the same…
This work explores the thermodynamic properties of charged BTZ black holes in a (2+1)-dimensional extended phase space framework. By analyzing temperature pressure relationships and heat capacity as functions of the…
In this article, magnetic fluids based on metal ferrites, namely NiFe2O4, CoFe2O4, and FeFe2O4, were synthesized. The sizes of the obtained magnetic nanoparticles were studied using transmission electron microscopy…
This study investigates the physicochemical properties of nanocomposites based on CdSe/CdS/ZnS triplet quantum dots. Methods for their synthesis, including stepwise deposition of CdS and ZnS shells to improve optical…
The synthesis of novel thieno[3,2-d]pyrimidine derivatives started with the reaction of 5-bromo-2 chlorobenzonitrile with ethyl-2-mercaptoacetate to give the compound AT-2. The addition of lactames to the formed AT-2…
In this work, an new estimate is obtained for the number of representations of a sufficiently large natural number as a sum of squares of four prime numbers. Additionally, the cardinality of the set of natural numbers…
The paper is devoted to the problem of random transverse vibrations of a circular plate taking into account the imperfect elasticity of the material. The dissipative characteristics of the hysteresis-type plate material…