bluuebunny/crossref_metadata_2025 huggingface dataset:
3-Nitroatenolol: First Synthesis, Chiral Resolution and Enantiomers’ Absolute Configuration
Authors: Sparaco Rosa , Cinque Pierfrancesco , Scognamiglio Antonia , Corvino Angela , Caliendo Giuseppe , Fiorino Ferdinando , Magli Elisa , Perissutti Elisa , Santagada Vincenzo , Severino Beatrice , Luciano Paolo , Casertano Marcello , Aiello Anna , Martins Viegas Gustavo Yuri , De Nucci Gilberto , Frecentese Francesco
Published: April 2024

4-Nitro and 7-nitro propranolol have been recently synthesized and characterized by us. (±)-4-NO2-propranolol has been shown to act as a selective antagonist of 6-nitrodopamine (6-ND) receptors in the right atrium of rats. As part of our follow-up to this study, herein, we describe the first synthesis of (±)-3-nitroatenolol as a probe to evaluate the potential nitration of atenolol by endothelium. Chiral chromatography was used to produce pure enantiomers. By using Riguera’s method, which is based on the sign distribution of ΔδH, the absolute configuration of the secondary alcohol was determined.
Sulfonic Functionalized Polydopamine Coatings with pH-Independent Surface Charge for Optimizing Capillary Electrophoretic Separations
Authors: Long Wenwen , You Mingyue , Li Jieli , Wang Yan , Wang Dan , Tao Xueping , Rao Li , Xia Zhining , Fu Qifeng
Published: April 2024

Enhancing the pH-independence and controlling the magnitude of electroosmotic flow (EOF) are critical for highly efficient and reproducible capillary electrophoresis (CE) separations. Herein, we present a novel capillary modification method utilizing sulfonated periodate-induced polydopamine (SPD) coating to achieve pH-independent and highly reproducible cathodic EOF in CE. The SPD-coated capillaries were obtained through post-sulfonation treatment of periodate-induced PDA (PDA-SP) coatings adhered on the capillary inner surface. The successful immobilization of the SPD coating and the substantial grafting of sulfonic acid groups were confirmed by a series of characterization techniques. The excellent capability of PDA-SP@capillary in masking silanol groups and maintaining a highly robust EOF mobility was verified. Additionally, the parameters of sulfonation affecting the EOF mobilities were thoroughly examined. The obtained optimum SPD-coated column offered the anticipated highly pH-independent and high-strength cathodic EOF, which is essential for enhancing the CE separation performance and improving analysis efficiency. Consequently, the developed SPD-coated capillaries enabled successful high-efficiency separation of aromatic acids and nucleosides and rapid cyclodextrin-based chiral analysis of racemic drugs. Moreover, the SPD-coated columns exhibited a long lifetime and demonstrated good intra-day, inter-day, and column-to-column repeatability.
Triel Bonds between BH3/C5H4BX and M(MDA)2 (X = H, CN, F, CH3, NH2; M = Ni, Pd, Pt, MDA = Enolated Malondialdehyde) and Group 10 Transition Metal Electron Donors
Authors: Wang Xin , Niu Zhihao , McDowell Sean A. C. , Li Qingzhong
Published: April 2024

A systematic theoretical study was conducted on the triel bonds (TrB) within the BH3∙∙∙M(MDA)2 and C5H4BX∙∙∙M(MDA)2 (M = Ni, Pd, Pt, X = H, CN, F, CH3, NH2, MDA = enolated malondialdehyde) complexes, with BH3 and C5H4BX acting as the electron acceptors and the square-coordinated M(MDA)2 acting as the electron donor. The interaction energies of these systems range between −4.71 and −33.18 kcal/mol. The larger the transition metal center M, the greater the enhancement of the TrB, with σ–hole TrBs found to be stronger than π–hole TrBs. In the σ–hole TrB complex, an electron-withdrawing substituent on the C opposite to the B atom enhances the TrB, while an electron-donating substituent has little effect on the strength of TrB in the Pd and Pt complexes but enhances the TrB in the Ni-containing complexes. The van der Waals interaction plays an important role in stabilizing these binary systems, and its contribution diminishes with increasing M size. The orbital effect within these systems is largely due to charge transfer from the dz2 orbital of M into the empty pz orbital of B.
Nickel(II)-Catalyzed Formal [3+2] Cycloadditions between Indoles and Donor–Acceptor Cyclopropanes
Authors: Quezada Víctor , Castroagudín Mariña , Verdugo Felipe , Ortiz Sergio , Zaragoza Guillermo , Nachtigall Fabiane M. , Reis Francisco A. A. , Castro-Alvarez Alejandro , Santos Leonardo S. , Nelson Ronald
Published: April 2024

This article describes the development of a nickel-catalyzed regio- and diastereoselective formal [3+2] cycloaddition between N-substituted indoles and donor–acceptor cyclopropanes to synthesize cyclopenta[b]indoles. Optimized reaction conditions provide the desired nitrogen-containing cycloadducts in up to 93% yield and dr 8.6:1 with complete regioselectivity. The substrate scope showed high tolerance to various substituted indoles and cyclopropanes, resulting in the synthesis of six new cyclopenta[b]indoles and the isolation of five derivatives previously reported in the literature. In addition, a mechanistic proposal for the reaction was studied through online reaction monitoring by ESI-MS, allowing for the identification of the reactive intermediates in the Ni(II) catalyzed process. X-ray crystallography confirmed the structure and relative endo stereochemistry of the products. This method enables the fast and efficient construction of fused indolines from readily accessible starting materials.
Molecular Dynamics Simulations of the Short-Chain Fluorocarbon Surfactant PFHXA and the Anionic Surfactant SDS at the Air/Water Interface
Authors: Jiao Jinqing , Li Tao , Zhang Guangwen , Xiong Jing , Lang Xuqing , Quan Xiaolong , Cheng Yiwei , Wei Yuechang
Published: April 2024

The research and development of alternatives to long-chain fluorocarbon surfactants are desperately needed because they are extremely toxic, difficult to break down, seriously harm the environment, and limit the use of conventional aqueous film-forming foam fire extinguishing agents. In this study, mixed surfactant systems containing the short-chain fluorocarbon surfactant perfluorohexanoic acid (PFHXA) and the hydrocarbon surfactant sodium dodecyl sulfate (SDS) were investigated by molecular dynamics simulation to investigate the microscopic properties at the air/water interface at different molar ratios. Some representative parameters, such as surface tension, degree of order, density distribution, radial distribution function, number of hydrogen bonds, and solvent-accessible surface area, were calculated. Molecular dynamics simulations show that compared with a single type of surfactant, mixtures of surfactants provide superior performance in improving the interfacial properties of the gas–liquid interface. A dense monolayer film is formed by the strong synergistic impact of the two surfactants. Compared to the pure SDS system, the addition of PFHXA caused SDS to be more vertically oriented at the air/water interface with a reduced tilt angle, and a more ordered structure of the mixed surfactants was observed. Hydrogen bonding between SDS headgroups and water molecules is enhanced with the increasing PFHXA. The surface activity is arranged in the following order: PFHXA/SDS = 1:1 > PFHXA/SDS = 3:1 > PFHXA/SDS = 1:3. These results indicate that a degree of synergistic relationship exists between PFHXA and SDS at the air/water interface.
Obtaining New Biocompatible Composite Materials with Antibacterial Properties Based on Diatomite and Biologically Active Compounds
Authors: Kabieva Saule , Zhumanazarova Gaziza , Zhaslan Rymgul , Zhumabayeva Gulistan , Ukhov Arthur , Fedorishin Dmitry , Gubankov Alexander , Tarikhov Farkhad , Yerkhan Ordabay , Irina Kurzina , Yerkassov Rakhmetulla , Bakibaev Abdigali
Published: April 2024

This study aimed to create new composite materials based on diatomite—a non-organic porous compound—through its surface modification with bioactive organic compounds, both synthetic and natural. Chloramphenicol, tetrahydroxymethylglycoluril and betulin were used as modifying substances. Composite materials were obtained by covering the diatomite surface with bioactive substance compounds as a solution and material dispersion in it. The materials were characterized by IR spectroscopy, SEM and X-ray photoelectron spectroscopy. For the biocomposites, the hemolytic effect, plasma proteins’ adsorption on the surface and the antibacterial activity of the obtained materials were studied. Results show that the obtained materials are promising for medicine and agriculture.
Accessible Eco-Friendly Method for Wastewater Removal of the Azo Dye Reactive Black 5 by Reusable Protonated Chitosan-Deep Eutectic Solvent Beads
Authors: Martínez-Rico Oscar , Blanco Lucía , Domínguez Ángeles , González Begoña
Published: April 2024

A novel approach to enhance the utilization of low-cost and sustainable chitosan for wastewater remediation is presented in this investigation. The study centers around the modification of chitosan beads using a deep eutectic solvent composed of choline chloride and urea at a molar ratio of 1:2, followed by treatment with sulfuric acid using an impregnation accessible methodology. The effectiveness of the modified chitosan beads as an adsorbent was evaluated by studying the removal of the azo dye Reactive Black 5 (RB5) from aqueous solutions. Remarkably, the modified chitosan beads demonstrated a substantial increase in adsorption efficiency, achieving excellent removal of RB5 within the concentration range of 25–250 mg/L, ultimately leading to complete elimination. Several key parameters influencing the adsorption process were investigated, including initial RB5 concentration, adsorbent dosage, contact time, temperature, and pH. Quantitative analysis revealed that the pseudo-second-order kinetic model provided the best fit for the experimental data at lower dye concentrations, while the intraparticle diffusion model showed superior performance at higher RB5 concentration ranges (150–250 mg/L). The experimental data were successfully explained by the Langmuir isotherm model, and the maximum adsorption capacities were found to be 116.78 mg/g at 298 K and 379.90 mg/g at 318 K. Desorption studies demonstrated that approximately 41.7% of the dye could be successfully desorbed in a single cycle. Moreover, the regenerated adsorbent exhibited highly efficient RB5 removal (80.0–87.6%) for at least five consecutive uses. The outstanding adsorption properties of the modified chitosan beads can be attributed to the increased porosity, surface area, and swelling behavior resulting from the acidic treatment in combination with the DES modification. These findings establish the modified chitosan beads as a stable, versatile, and reusable eco-friendly adsorbent with high potential for industrial implementation.
Antiprotozoal Activity of Plants Used in the Management of Sleeping Sickness in Angola and Bioactivity-Guided Fractionation of Brasenia schreberi J.F.Gmel and Nymphaea lotus L. Active against T. b. rhodesiense
Authors: Vahekeni Nina , Brillatz Théo , Rahmaty Marjan , Cal Monica , Keller-Maerki Sonja , Rocchetti Romina , Kaiser Marcel , Sax Sibylle , Mattli Kevin , Wolfram Evelyn , Marcourt Laurence , Queiroz Emerson Ferreira , Wolfender Jean-Luc , Mäser Pascal
Published: April 2024

Folk medicine is widely used in Angola, even for human African trypanosomiasis (sleeping sickness) in spite of the fact that the reference treatment is available for free. Aiming to validate herbal remedies in use, we selected nine medicinal plants and assessed their antitrypanosomal activity. A total of 122 extracts were prepared using different plant parts and solvents. A total of 15 extracts from seven different plants exhibited in vitro activity (>70% at 20 µg/mL) against Trypanosoma brucei rhodesiense bloodstream forms. The dichloromethane extract of Nymphaea lotus (leaves and leaflets) and the ethanolic extract of Brasenia schreberi (leaves) had IC50 values ≤ 10 µg/mL. These two aquatic plants are of particular interest. They are being co-applied in the form of a decoction of leaves because they are considered by local healers as male and female of the same species, the ethnotaxon “longa dia simbi”. Bioassay-guided fractionation led to the identification of eight active molecules: gallic acid (IC50 0.5 µg/mL), methyl gallate (IC50 1.1 µg/mL), 2,3,4,6-tetragalloyl-glucopyranoside, ethyl gallate (IC50 0.5 µg/mL), 1,2,3,4,6-pentagalloyl-β-glucopyranoside (IC50 20 µg/mL), gossypetin-7-O-β-glucopyranoside (IC50 5.5 µg/mL), and hypolaetin-7-O-glucoside (IC50 5.7 µg/mL) in B. schreberi, and 5-[(8Z,11Z,14Z)-heptadeca-8,11,14-trienyl] resorcinol (IC50 5.3 µg/mL) not described to date in N. lotus. Five of these active constituents were detected in the traditional preparation. This work provides the first evidence for the ethnomedicinal use of these plants in the management of sleeping sickness in Angola.
Sn(IV)porphyrin-Incorporated TiO2 Nanotubes for Visible Light-Active Photocatalysis
Authors: Shee Nirmal Kumar , Lee Gi-Seon , Kim Hee-Joon
Published: April 2024

In this study, two distinct photocatalysts, namely tin(IV)porphyrin-sensitized titanium dioxide nanotubes (SnP-TNTs) and titanium dioxide nanofibers (TNFs), were synthesized and characterized using various spectroscopic techniques. SnP-TNTs were formed through the hydrothermal reaction of NaOH with TiO2 (P-25) nanospheres in the presence of Sn(IV)porphyrin (SnP), resulting in a transformation into Sn(IV)porphyrin-imbedded nanotubes. In contrast, under similar reaction conditions but in the absence of SnP, TiO2 (P-25) nanospheres evolved into nanofibers (TNFs). Comparative analysis revealed that SnP-TNTs exhibited a remarkable enhancement in the visible light photodegradation of model pollutants compared to SnP, TiO2 (P-25), or TNFs. The superior photodegradation activity of SnP-TNTs was primarily attributed to synergistic effects between TiO2 (P-25) and SnP, leading to altered conformational frameworks, increased surface area, enhanced thermo-chemical stability, unique morphology, and outstanding visible light photodegradation of cationic methylene blue dye (MB dye). With a rapid removal rate of 95% within 100 min (rate constant = 0.0277 min−1), SnP-TNTs demonstrated excellent dye degradation capacity, high reusability, and low catalyst loading, positioning them as more efficient than conventional catalysts. This report introduces a novel direction for porphyrin-incorporated catalytic systems, holding significance for future applications in environmental remediation.
Studies of the Functionalized α-Hydroxy-p-Quinone Imine Derivatives Stabilized by Intramolecular Hydrogen Bond
Authors: Gaile Anastasija , Belyakov Sergey , Dūrena Ramona , Griščenko Ņikita , Zukuls Anzelms , Batenko Nelli
Published: April 2024

In this work, reactions between 6,7-dichloropyrido[1,2-a]benzimidazole-8,9-diones with different benzohydrazides were studied. Nucleophilic substitution at C(6) was followed by isomerization and led to α-hydroxy-p-quinone imine derivatives. Synthesized compounds represent a combination of several structural motifs: a benzimidazole core fused with α-hydroxy-p-quinone imine, which contains a benzamide fragment. X-ray crystallography analysis revealed the formation of dimers linked through OH···O interactions and stabilization of the imine form by strong intramolecular NH···N hydrogen bonds. The protonation/deprotonation processes were investigated in a solution using UV–Vis spectroscopy and a 1H NMR titration experiment. Additionally, the electrochemical properties of 6,7-dichloropyrido[1,2-a]benzimidazole-8,9-dione and its α-hydroxy-p-quinone imine derivative as cathode materials were investigated in acidic and neutral environments using cyclic voltammetry measurements. Cathode material based on 6,7-dichloropyrido[1,2-a]benzimidazole-8,9-dione could act as a potentially effective active electrode in aqueous electrolyte batteries; however, further optimization is required.
Inflammatory-Targeted Lipid Carrier as a New Nanomaterial to Formulate an Inhaled Drug Delivery System
Authors: Maretti Eleonora , Gioia Federica , Rustichelli Cecilia , Molinari Susanna , Leo Eliana
Published: April 2024

There is a pressing need for efficacious therapies in the field of respiratory diseases and infections. Lipid nanocarriers, administered through aerosols, represent a promising tool for maximizing therapeutic concentration in targeted cells and minimizing systemic exposure. However, this approach requires the application of efficient and safe nanomaterials. Palmitoylethanolamide (PEA), an endocannabinoid-like endogenous lipid, plays a crucial role in providing protective mechanisms during inflammation, making it an interesting material for preparing inhalable lipid nanoparticles (LNPs). This report aims to preliminarily explore the in vitro behavior of LNPs prepared with PEA (PEA-LNPs), a new inhalable inflammatory-targeted nanoparticulate drug carrier. PEA-LNPs exhibited a size of about 250 nm, a rounded shape, and an marked improvement in PEA solubility in comparison to naked PEA, indicative of easily disassembled nanoparticles. A twin glass impinger instrument was used to screen the aerosol performance of PEA-LNP powders, obtained via freeze-drying in the presence of two quantities of mannose as a cryoprotectant. Results indicated that a higher amount of mannose improved the emitted dose (ED), and in particular, the fine particle fraction (FPF). A cytotoxicity assay was performed and indicated that PEA-LNPs are not toxic towards the MH-S alveolar macrophage cell line up to concentrations of 0.64 mg/mL, and using coumarin-6 labelled particles, a rapid internalization into the macrophage was confirmed. This study demonstrates that PEA could represent a suitable material for preparing inhalable lipid nanocarrier-based dry powders, which signify a promising tool for the transport of drugs employed to treat respiratory diseases and infections.
Understanding Religious Music: A Smorgasbord
Authors: Zangwill Nick
Published: April 2024

Understanding religious music is challenging. Indeed, the whole idea can seem perplexing and problematic. In this paper, a number of ways of understanding religious music are sketched. Seven main models are distinguished: the side-effect model, the ringtone model, the honey model, the addition model, the fitting beauty model, the organic unity model, and the similarity model. Some issues concerning Bach’s Sacred Cantatas are then considered in order to see how these approaches apply in one particularly controversial and puzzling example.
Studying and understanding the Islam world by history students of the Petrozavodsk State University
Authors:   Department of Foreign History, Institute of History, Political and Social Sciences, Petrozavodsk State University, Smirnova Nataliya Vladimirovna , Slyusar Elena Vladimirovna ,   Reader Services Department No. 1, Scientific Library, Petrozavodsk State University
Published: April 2024

The article analyzes the impressions and statements of foreign and Russian authors of the late 19th - early 20th centuries about the history and culture of the Muslim world. The importance of original orientalist publications from the rare book reading room collection of the Scientific Library of the Petrozavodsk State University in the study and understanding by student historians of the Islam world is shown.
Improving cost management methods at enterprises in the construction materials industry
Authors:   Faculty of Economics, Management and International Relations, Moscow University for the Humanities, Erofeeva Yuliya Nikolaevna
Published: April 2024

The justified characteristics of the selection of cost accounting method in the Russian practice of enterprises in the construction materials industry are presented. The article examines the theoretical foundations of the concept of the standard cost method, a system for calculating marginal costs. Calculation methods are defined with justification for the applied coefficients.
The current state and prospects for the development of the flower market in the Kaluga region
Authors:   Kaluga branch of the Russian State Agrarian University — Moscow Timiryazev Agricultural Academy, Kaluga, Russia, Ovcharenko Y. E. , Malakhova S. D. ,   Kaluga branch of the Russian State Agrarian University — Moscow Timiryazev Agricultural Academy, Kaluga, Russia, Akimova L. P. ,   Kaluga branch of the Russian State Agrarian University — Moscow Timiryazev Agricultural Academy, Kaluga, Russia, Volkova L. V. ,   Kaluga branch of the Russian State Agrarian University — Moscow Timiryazev Agricultural Academy, Kaluga, Russia
Published: April 2024

The article contains an analysis of the current state of the flower industry in the Kaluga region. The analysis is the justification for the development of a strategy for the development of a flower cluster. The flower market is highly competitive, with a large number of both local and international players. The development and implementation of a marketing strategy is critically important for the success of a flower cluster in modern market conditions. The article discusses the following aspects: determining target sales volumes; competition analysis and cluster positioning; a system for promoting and increasing product awareness. The development of the strategy is proposed based on an analysis of the market situation, the competitive environment and the potential of the region. The analysis allowed us to draw conclusions about the current state of the flower market, the level of development of enterprises belonging to the Kaluga region flower cluster and trends in the development of the flower market. The provisions of the article were used in the development of a strategy for the creation and development of a cluster for the production of floral products in the Kaluga region
Efficiency of investment activity in the dairy subcomplex
Authors:   Russian Timiryazev State Agrarian University, Moscow, Russia, Postnikova L. V. , Lebedev K. A. ,   Russian Timiryazev State Agrarian University, Moscow, Russia, Dzhikiya K. A. ,   Russian Timiryazev State Agrarian University, Moscow, Russia, Romanova A. A. ,   Russian Timiryazev State Agrarian University, Moscow, Russia
Published: April 2024

The article presents the results related to the evaluation of the effectiveness of investment activities in the dairy subcomplex. It is established that investments are an important component of the economic development of the dairy subcomplex, the effectiveness of which depends on a set of factors of the macro- and microeconomic environment, its organizational and economic characteristics, the investment strategy of enterprises, objects and sources of investment, the period for which capital is invested, the certainty of its future effect and the associated risk level. It was found out that in the conditions of low competitiveness of dairy subcomplex enterprises, there is a need to use effective investment projects, which significantly strengthened the role of investment efficiency analysis as a tool within which it is possible to justify, evaluate and select priority investment projects. It is determined that the task of analyzing the effectiveness of investments is the calculation of profits and cash flows, the assessment of their effectiveness, the identification of the influence of uncertainty factors on their profitability, the selection of optimal investment projects. It is advisable to organize the analysis of the effectiveness of investments in the following areas: the definition of subjects and objects of analysis; the choice of organizational forms of analysis, depending on the organizational structure and the distribution of responsibilities between individual performers; the preparation of the analysis program and its information support; analytical data processing, design and generalization of the analysis results. The proposed methodological approach to the analysis of investment efficiency takes into account the conditions of an unstable market environment (variable macroeconomic conditions, insufficient supply of dairy raw materials, uncertainty about wholesale purchase and sale prices), makes it possible to determine the effectiveness of investments, conduct risk analysis by simulation and predict data for risk analysis using regression methods.
ANALYSIS OF FACTORS AFFECTING THE FATIGUE STRENGTH OF METALLURGICAL EQUIPMENT PARTS
Authors: Oleksii Hrechanyi , Tetyana Vasilchenko , Vadym Badlo , Mykhailo Chuvalskyi , Oleksandr Padalka , Volodymyr Parkhomenko
Published: April 2024

The causes of fatigue failure of metallurgical equipment parts are analyzed. The relationship between the effect of the quality of surface treatment of the part on the fatigue strength has been established. The influence of local stress concentrators on fatigue strength is determined. These are recommendations for increasing the fatigue strength of the finished part.
THE INFLUENCE OF THE CHEMICAL COMPOSITION OF MATERIALS OF DRILLING BITS ON THE MAIN CAUSES OF THEIR DESTRUCTION
Authors: Dmytro Petryna , Roman Yakym
Published: April 2024

Three-layer drill bits work under increased loads and wear, which can cause their rapid failure. The complex design of the drills is also the reason for the difficulty of controlling their overall strength. The analysis of the types of destruction, together with the analysis of the chemical composition of steels, can provide answers to many questions about the durability of drill bits under different operating conditions. Differences in the chemical composition of steels, deviations in the technological process of straightening, non-compliance with drilling technology can cause the failure of drill bits in the short term of their operation. These changes were controlled by the DI strength criterion with a further possible solution of this problem.
MECHANICAL PROPERTIES OF MELT-QUENCHED PB-BA-SN ALLOYS FOR GRIDS OF LEAD ACID BATTERIES
Authors: Viktor Dzenzerskiy , Volodimer Ivanov , Olena Viduta
Published: April 2024

Mechanical properties and structure of specimens of melt-quenched lead alloyed with Ba and Sn for batteries grids have been studied. It has been shown that during isothermal aging at 80°C alloys do show no tendency to recrystallize and lose strength. The results of studies of the phase composition have allowed us to propose a mechanism of alloy strengthening during the ageing process. Strengthening of the Pb–Ba–Sn alloys proceeds due to precipitation hardening and formation of Pb3Ba precipitates that further transform to inclusions of Sn5Ba phase. Barium has no modification effect on crystallization processes of the alloys. The grains of lead-based solid solution become finer because more crystallization nuclei form under higher overcooling.
NUMERICAL SIMULATION OF UNSTEADY PROCESSES OF SELECTIVE LASER MELTING OF METAL POWDERS
Authors: Stanislav Dovgii , Bohdan Dovgii , Oleg Kopiyka , Svitlana Moiseienko , Dmytro Redchyts , Ulyana Tuchyna
Published: April 2024

Mathematical modeling of non-stationary processes of selective laser melting of metal powders is considered. The general mathematical formulation of the problem of selective laser melting of metal powders is reduced to the formulation of separate structurally interconnected problems. Such as: the problem of non-stationary heat transfer taking into account phase transitions when heating metal powders with a moving laser beam; the problem of the dynamics of liquid metal in a molten bath; the task of determining the non-stationary shape of the free surface of the melt bath in the presence of recoil pressure. As a result of the carried out computer modeling, the distribution of the temperature field in the calculation area with the selection of the liquid zone was obtained. The dependences of the width and depth of the melt bath on the laser movement speed and the laser spot diameter are plotted.
CONTROL OF THE GEOMETRY OF THE TRANSITIONAL CURVE OF THE PROFILE AND THE SIZE OF THE LIMIT DIAMETER OF THE CYLINDRICAL GEAR
Authors: Volodymyr Melnyk , Anatoliy Krivosheya , Ruslan Fyl
Published: April 2024

Information is given on the use of cylindrical gears. The influence of the geometry of the transition curve on other parameters is considered. With the development of numerically controlled machines and 3D printing, it becomes possible to manufacture gears with any geometry, in particular, it is possible to manufacture a transition surface with any parameters of the transition curve. The formula for determining the limit diameter is presented. The above formula is valid for gears that do not have undercutting. As can be seen from the obtained formula, the maximum diameter depends on the module, the number of teeth, the angle of the profile, the offset and other parameters of the initial contour. An example of a formed depression of a gear wheel is presented. The results of calculation and modeling of the value of the limit diameter depending on different values of the radius of curvature of the output contour were obtained.
COMPUTER SIMULATION OF THE NON-STATIONARY PROCESS OF THE SUPERSONIC OVEREXPANDED JET DEVELOPMENT
Authors: Oleg Polevoy , Dmytro Redchyts , Uliana Tuchyna
Published: April 2024

Questions of numerical simulation of non-stationary process of the development of a supersonic overexpanded jet are considered. Unsteady Reynolds-averaged Navier-Stokes equations (URANS) of compressible flows, written in an arbitrary coordinate system, along with the Spalart-Allmaras one-equation differential turbulence model are applied. The calculations of non-stationary formation of an air cold supersonic jet during the blowing through a conical Laval nozzle (simulation of engine start-up) were made. The physical features of the shock and acoustic waves generation and propagation are discussed. In the stationary phase an overexpanded free supersonic turbulent jet is formed, which includes a Mach disc in its structure. The obtained results were compared with experimental data and calculations by other authors based on the ANSYS Fluent and FloEFD CFD tools.
СONSTRUCTIVE-SYNTHESIZING MODELING OF THE DETERMINISTIC FRACTAL TIME SERIES
Authors: Vktor Shynkarenko , Artem Zhadan
Published: April 2024

This study represents the usage of the constructive-synthesizing modeling for deterministic fractal time series forecasting by finding the appropriate model. The constructive-synthesizing modeling was already successfully used for generation various time series using L-system and normal distribution. The main purpose of this research is the opposite process – find the model, which is related to the given values. The composite constructor has been developed and it consists of four interconnected constructors, which are performing actions from generating the time series to finding a corresponding model using genetic algorithm. The software solution has been developed to achieve the automatization of the testing process. There are four main stages of the experiments with different complexity of the time series models, starting with one-rule with four characters in the right part and ending with one-to-three rules with four-to-ten characters in the right part and complex axiom. The practical application of this solution is requiring further studying with using stochastic real-life time series.
COMBINED SORTING ALGORITHMS
Authors: Viktor Shynkarenko , Oleksii Makarov
Published: April 2024

This study represents the usage of data preprocessing for performance improvement of sorting algorithms. Combining of different basic sorting algorithms was already successfully used to outperform any sole algorithm. The purpose of this research is to discover and estimate different ways to reorganize unsorted data just before executing the main sorting algorithm. Five preprocessing technics were developed and tested in combination with cocktail sort, insertion sort and quick sort. Time efficiency was estimated by comparing time of sole sorting algorithm and combined algorithm which includes preprocessing. Further studying of preprocessing methods and their impact on different sorting algorithms is required.
THE INGOTS CUTTING SUBSYSTEM ALGORITHM FOR THE DECISION SUPPORT MANAGEMENT SYSTEM OF MULTI-STAGE ROLLED PRODUCTION
Authors: Timur Zheldak , Illia Ziborov
Published: April 2024

The algorithm of the subsystem of ingots cutting for the Decision support management system of multi-stage rolling production is proposed. The algorithm provides the parallel use of orders for products of different assortments. In contrast to previously known solutions, the size of an order for a certain type of finished rolling products can exceed the size of one melt. This solution is considered to be a scientific novelty of the proposed approach and at the same time corresponds to real orders at metallurgical enterprises. The given algorithm was applied to the daily load planning of one of the metallurgical plants in the Dnipropetrovsk Region. A practical test is to demonstrate that the algorithm application to real orders improves the technical and economic indicators of production.
ANALYSIS OF THE PROBLEMS OF INCREASING THE EFFICIENCY OF ANALYSIS OF BIG WEB DATA IN THE BUSINESS SPHERE
Authors: Stanislav Maliienko , Tatyana Selivorstova
Published: April 2024

Now the problem of analyzing big web data is becoming more and more complex. The article describes some of the main challenges that companies face when analyzing large amounts of data on the web. First, the volume of data and its influx pose a challenge for businesses to process it quickly in real time. Secondly, the quality of the data is not always high enough and it needs to be cleaned before analysis. Finally, the need to improve the performance of data analysis algorithms means that companies must use the latest technologies and data analysis methods in order to ensure fast and efficient decision-making based on the results obtained.
NEURAL NETWORK PREDICTION OF PRICES ON THE STOCK MARKET
Authors: Yurii Pertsev , Larysa Korotka
Published: April 2024

In the modern world of financial markets are showing more and more interest in systems that can accurately and efficiently predict the future price of financial instruments. Information technologies that exist at the moment make it possible to analyze and use highly loaded systems such as neural networks to predict the financial performance of a company. This article discusses the use of neural networks to predict the price of shares in the financial market. The possibilities of neural networks for predicting stock prices are considered due to the fact that neural networks have many hidden blocks that allow the model to adapt to complex relationships between company indicators and its stock price. An example of a RNN neural network is given that can work with sequential data such as hourly series. For an example of building a model, Apple was chosen as one of the largest companies that is included in the S&P 500 list of the most influential companies in the American market.
COGNITIVE APPROACHES TO INTELLIGENCE: ASYMPTOTIC RATIONALITY AND CONTINUUM OF DISTINCTION TASKS
Authors: Yurii Prokopchuk
Published: April 2024

Having artificially intelligent machines that think, learn, reason, experience, and can function autonomously, without supervision, is one of the most intriguing goals in all of Computer Science. The goal of this paper is to outline some basic principles and concepts that are the backbone of real, autonomous Artificial Intelligence. The design of hybrid artificial intelligence methods and algorithms is presented using the limiting generalization paradigm. The results of the study can be used to create cognitive agents and robots, as well as the cognitive Internet.
ANALYSIS OF THE FUZZY LOGIC PERSPECTIVES APPLICATION IN INTERNET OF THINGS NETWORKS
Authors: Eduard Dovidovsky , Anton Guda
Published: April 2024

The basic principles, fundamental characteristics and directions of practical application of the concept of the Internet of Things are investigated, an analysis of the development of the concept of the Internet of Things and its main networks is carried out. The basic concepts of fuzzy logic concepts, the theory of fuzzy sets and fuzzy inference algorithms are analyzed. When using the theory of fuzzy sets and fuzzy logic in the field of the concept of the Internet of Things and its main networks, the most preferable is the use of the Mamdani algorithm, the advantage of which is that the knowledge bases created on its basis are transparent and intuitive, while when using other algorithms, it becomes difficult to choose linear dependencies between the studied parameters.
MULTIFACTOR ANALYSIS OF THE EFFICIENCY OF THE FERROALLOY PROCESS
Authors: R. Ponomarenko , Yurii Proidak , Volodymyr Gladkykh , Artem Ruban , Andrii Proidak
Published: April 2024

Ore-reducing ferroalloy processes must be considered as a relationship of parameters and characteristics of subsystems and elements. The maximum energy capacity of the furnace and its productivity is achieved both due to the design parameters of the bath, the short network, the power of the furnace transformer, the diameter of the self-ignition electrodes, as well as the electrotechnological and thermophysical properties of the initial charge materials, ore-slag melt and final ferroalloy. The amount of carbon is one of the most significant technological parameters of the carbon reduction process for the production of manganese ferroalloys. In the work, the most significant final indicators are adopted and their correlation with electrical characteristics and technological parameters is determined.
DEVELOPMENT OF SOFTWARE FOR CALCULATING OPTIMAL CUTTING MODES
Authors: Vladlen Karabut
Published: April 2024

In the trial version of the Delphi development environment in the Object Pascal language, a program has been developed that allows you to: for given specific processing conditions, calculate the optimal cutting conditions, build tables. The use of a program developed in the Delphi development environment will automate and optimize the processes of calculations, building tables, and as a result, reduce time costs and increase the accuracy of calculations. The use of the considered information technologies in the educational process provides a specialist in mechanical engineering with the opportunity to work quickly and efficiently.
Utjecaj svojstva kože kod
proizvodnje obuće
Authors: Rastek Ivan
Published: April 2024

Ovaj rad sadrži opis kemijskih i fizikalnih svojstava potplata i gornjeg dijela kože te njihov utjecaj na proizvodnju cipela.
Correlative Language and Creativity Metacognition Interpretation for Business Setups
Authors: Rivera Joel Laffita
Published: April 2024

Although language and creativity used to be analyzed as separate subjects, all human society created things show signs of correlation between them. Observable evidences suggest that, there is an intellectual correlation phenomenon between these faculties when successful business approaches and development refer. And the basis observation of this is the entrepreneurial mindset novel-idea acquisition and development.
The research relies on the Metacognition Theory to assign the subject. And to provide ametacognition language and creativity correlation model to decode the entrepreneurial mindset novel-idea acquisition and development.
A qualitative method has been used. This research criterium has involved the reviewing of academic and scientific research works, books, and Internet accredited websites. Materials that are related to the subject analyzed. The results of this study are beneficial to all academic and scientific fields relate to the topic presented.
EPIDEMICS ON THE MACEDONIAN FRONT (1916-1918)
Authors: Josimovska Verica , Cackov Oliver
Published: April 2024

World War I, like the previous two Balkan wars, took place on two fronts on a larger or smaller scale.One fought fighting on the warfare sides, and the other front was fought with outbreaks of infectious diseases. TheBalkans, especially Macedonia, were also the hotspot of several epidemic waves during these years of war. Startingwith cholera in 1913. military forces and the local population, in the following years of war, almost simultaneouslyhit the epidemic of stomach typhoid, feedback fever, damn typhoid, and dysentery. In the wake of the militaryactions of the Macedonian Front, malaria was the most dangerous infectious disease in the ranks of all armies, adisease that was expressed in less or greater intensity in all years of war. Reports of the warred sides' sanitationreported a large percentage of the sick, but also a high percentage of measles. The victims of the end of the war in1918. will increase with the appearance of a flu epidemic known as Spanish fever (Spanish flu) that will take apandemic scale. A pandemic that will take about 50 million people worldwide between 1918 and 1919, significantlymore than the total number of victims in World War I. The role of the sanitation of the Balkan countries is great, butalso of the large number of foreign missions that dealt with this situation by assisting the military and localpopulations.
THE PLACE OF THE SERBIAN PEOPLE IN THE WORK BYZANTISM AND SLAVISM BY KONSTANTIN LEONTIEV
Authors: Janković Nikola
Published: April 2024

The aim of the research is to determine the place of the Serbian people in the work Byzantism andSlavism by Konstantin Leontiev. It is known that this capital work of the author influenced the political climate atthe end of the nineteenth century in Russia. It confronts two basic ideas: Byzantism as the bearer of civilizationalvalues and Slavism as the bearer of the national spirit. An overview of these two terms is provided with relevantcomments from experts who have dealt with this field. Since the Serbian people are historically present in bothmentioned circles, it is necessary to determine their exact place. Data were collected to the greatest extent from thework itself, but also from all available relevant published works on this topic. The general historical background ofthe work itself is the resolution of the Eastern Question (the collapse of the Turkish Empire) and the further fate ofthe peoples who are part of it, along with the role of Russia in the entire process. Comparisons were mainly madewith already existing descriptions of other Slavic peoples and peoples in the area of former Byzantium, primarilyGreeks and Turks. First of all, the situation in the cultural and political life of the Serbian people during thenineteenth century is analyzed with reference to the most important events of that time. Due attention was paid tothe Russian-Bulgarian and Serbian-Bulgarian relations at the time: the possibilities of their further cooperation, therestoration of medieval states, but also the conflicts that inevitably arose as a result of the actions and influence ofthe great powers were considered. In addition, an exhaustive account of the Serbian people and their historical fate isgiven, where it can be seen that of all the Slavic peoples listed at the time, it was the most fragmented and divided,but at the same time the most ready and determined to stand up to the Turkish occupying power. There were alsodescriptions of the bad character traits of the Serbian people. On the one hand, there is self-sacrifice, readiness tofight for liberation and fearlessness, while on the other hand there are limited forces and the impossibility of fightingindependently without Russian support. In addition, there is the eternal struggle for possible supremacy in theBalkans between the Serbs, Bulgarians and Greeks, as well as the desire of the Serbs to fit into modern Europeansociety according to Western patterns as quickly as possible. The author sees this as a distinctly bad trait. Thegeneral conclusion is that the Serbs in the mid-nineteenth century are a nation that is at a turning point betweentraditional and new European culture and that its further political and cultural development will most likely lead tothe creation of a new Balkan federation in which there will be few Orthodox and Byzantine elements, or in generalfactors that could lead to disagreements among the peoples involved.
VOCAL QUARTETS – TRADITION AND MODERNITY
Authors: Koteterova-Dobreva Binka
Published: April 2024

Working in large professional choirs and ensembles extremely evolve the musical singing skills andabilities of each singer. The performance of complicated composer scores, giving "life and emotionality" to thenotes, contributes to the further development, improvement and professional experience of singing choristers. Inwell-established folk choirs and ensembles, as well as the institutions for higher musical education, good performersmeet, and more and more often we witness new vocal quartets - successors to already existing ones.The aim of each newly formed vocal quartet is, on the one hand, to assimilate and imitate an existing one, but on theother hand, to achieve a new, better sonority, vocal unification, mastery of a stylish and effective concert repertoire,attractiveness of its presentation and upgrading at the level achieved by previous quartets, up to this point.. In thefollowing lines, I will present vocal quartets arranged chronologically by their creation: "Sestri Kushlevi", "Balgarka- Dzhuniar", "Slavey" and "Abagar"
DIAGNOSTIC OF THE SCHOOL ANXIETY CONCERNING THE EMOTIONAL INTELLIGENCE
Authors: Drunchilova Valentina
Published: April 2024

The report examines the necessary changes in the modern education system, through which answers aregiven to the adequate needs of society and the requirements of every student. The emphasis is placed on the role ofthe school in building important qualitative characteristics of the student’s personality, related to his moral andemotional development. The need to achieve a balance between the rational and the emotional in the learningprocess is emphasized. In the context of the problem of the development of emotional intelligence, questions relatedto the emotional status of the student at primary school age are considered. Special attention is paid to the level ofschool anxiety amongstudents in the initial educational stage of primary education. The analyzed data from theconducted empirical study make it possible to outline difficulties and deficits in the emotional development of thechild at primary school age and, on this basis, identify possible ways to overcome them.
Decision support system for purchasing light fire extinguisher brands (APAR) on household needs using the weighted product (WP) method
Authors: Maulana Dimas Fajar , Heryana Nono , Ridwan Taufik
Published: April 2024

Fire, as a serious disaster with destructive impacts involving loss of material and human lives, is mainly triggered by electrical short circuits due to massive construction and the use of cables that do not comply with standards. The importance of developing electric power that complies with safety standards to protect people and property cannot be overstated. Electrical integration is aimed at increasing system efficiency, but electrical short circuits remain the main cause of fires, accounting for 45% of cases in Indonesia in 2021. To reduce the risk, preventive measures are needed such as repairing the electrical network, using standard equipment, and educating the public. A light fire extinguisher (APAR) is one of the highly recommended fire prevention media. The appropriate APAR for household needs is the Chemical Powder / Dry Cemical type because it is almost effective for all classes of fires, especially for electrical short circuits. But in purchasing we are faced with the many brands available as well as limited needs, desires and financial capabilities. In this context, a web-based Decision Support System (DSS) was developed using the Weighted Product (WP) method to select the Brand of Light Fire Extinguisher (APAR). The WP method gives weight to the criteria of price, quality and reliability, helping households choose an APAR that suits their needs and budget. The application of this method is expected to minimize errors in selecting the APAR brand, increase accuracy, and make it easier to use for those who want to make a purchase. This SPK makes a positive contribution in helping users make APAR purchasing decisions that suit their needs and preferences.