bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of aqueous environments on the stability of modified polylactide materials
Authors:   Lviv Polytechnic National University, Katruk D.S. , Levytskyi V.Ye. , Masiuk A.S. , Kulish-Pelenska B.І. , Kysil Kh.V. , Laruk Yu.V.
Published: February 2025

The effects of fillers of different nature (chalk and native starch) and plasticizer (epoxidized soybean oil), their concentration, and process temperature on the patterns of water absorption of polylactide materials were investigated. Based on the obtained data, the diffusion coefficients of water in polylactide composites and the activation energy of the diffusion process were determined. It was found that the equilibrium water absorption of the developed materials is relatively high and equals to 3–5 wt.%, regardless of the nature of the additives, while an increase in water temperature leads to an increase in water absorption values. It was established that the process of water absorption of materials based polylactide filled with starch occurs faster and requires less energy to activate the process. Based on the results of infrared spectroscopy, a shift of the typical absorption bands of polylactide starch-containing materials was revealed, indicating the presence of intermolecular interactions in the system. The stability of the developed polylactide materials in acidic and alkaline water environments was determined; in particular, it was found that in an acidic environment, starch-containing materials demonstrate a reduced rate of degradation compared to an alkaline environment. At the same time, in an alkaline environment, the destruction of samples occurs with high values of weight loss, regardless of the composition of the composite. Alkali concentration affects both the rate of destruction of composites and the maximum values of weight loss, especially for composites with a small amount of filler.
DES-assisted electrodeposition and characterization of an electrocatalyst for enhanced urea oxidation in green hydrogen production
Authors:   Ukrainian State University of Science and Technologies, Protsenko V.S. , Shaiderov D.A. ,   Ukrainian State University of Science and Technologies, Sukhatskyi O.D. ,   Ukrainian State University of Science and Technologies, Butyrina T.E. ,   Ukrainian State University of Science and Technologies, Korniy S.A. ,   Ukrainian State University of Science and Technologies,   Karpenko Physico-Mechanical Institute of the NAS of Ukraine, Danilov F.I. ,   Ukrainian State University of Science and Technologies
Published: February 2025

An important task of modern materials science is the development of highly efficient electrocatalysts for green hydrogen production. Specifically, this involves the urea oxidation reaction (UOR), which is an energetically advantageous and attractive alternative to the anodic oxygen evolution reaction, coupled with hydrogen evolution at the cathode. In this work, we present for the first time the use of systems based on a new generation of environmentally friendly room-temperature ionic liquids – deep eutectic solvents (DESs) – for the electrodeposition of electrocatalysts for UOR. The electrochemical performance of electrodeposited nanocomposite Ni–CeO2 electrocatalysts was evaluated in alkaline solution, showing an appreciable reduction in the anodic potential of UOR compared to oxygen evolution, reaching up to approximately 0.2 V at a current density of 0.1 mA cm–2. The obtained results are significant for the development of electrochemical synthesis methods for electrocatalysts used in green renewable energy.
Identifikasi Pola Prilaku Belajar Mahasiswa Pada Platform Learning Management System Dengan Algoritma K-Means
Authors: Muhammad Alam Ridho , Hazriani Hazriani , Latied Arda Abdul , Ikhwan Mardin Muhammad
Published: February 2025

This study aims to explain students' behavior in accessing the kalam.umi.ac.id learning platform and its impact on student academic performance. It analyzes data collected from students' access to the platform during 12 sessions in one semester for the Islamic communication subject taught by Professor Surani. The data includes students' access times, access frequency, and academic performance such as assignment grades, midterm exams, and final exams. Through data processing methods, correlation analysis, and cluster optimization, the study found a positive relationship between access times, midterm exams, final exams, and assignments with students' final grades. The higher these variables, the higher the students' final grades. However, this relationship is not always consistent across different variables. In this study, the Elbow method was used to determine the optimal number of clusters by identifying the point where the variance reduction becomes less significant. Additionally, the Sum of Square Error (SSE) was analyzed to understand the sharp change followed by a gradual decrease in the value of K until stability is reached. Clustering results using the K-Means algorithm showed the presence of three student clusters based on their learning behavior. Cluster 0 is the largest, consisting of 176 students. Cluster 1 has 57 students, and cluster 2 is the smallest with 17 students. These clusters provide insights into varying student learning patterns, including differences in final grades and access frequency. These findings can be used as a basis for developing more effective and personalized learning strategies for students.
Sistem Monitoring Kecepatan Otoped Listrik Menggunakan Baterai LiFePO4 sebagai Transportasi Alternatif
Authors: Firyal Adila Ahmad , Maulana Abdullah Rafli , Irianto Irianto , Septi Yanaratri Diah , Sutedjo Sutedjo , Renny Rakhmawati Renny Rakhmawati
Published: February 2025

Autoped has become a popular alternative in environmentally friendly urban transportation. It uses batteries as the main power source to drive their electric motors. However, efficient and optimal battery usage is essential to maintain the performance and durability of autoped. This study aims to design a speed monitoring system for autoped using LiFePO4 batteries by considering variations in user loads. This monitoring system informs autoped drivers about the speed when used and battery usage. This electric autoped is equipped with a DC brushed motor with a specification of 24 Volt/500 Watt. The speed is measured using a metal proximity sensor that functions without direct contact, thus ensuring consistent measurements and reducing the risk of errors due to physical interaction. In addition, a load cell sensor with a maximum weight measurement of 100 kg is used to classify user's weight which is divided into three variations: 35-45 kg, 46-55 kg, and 56-65 kg. As the main energy source, this system uses a LiFePo4 battery with a specification of 24 Volt/36 Ah. The system was tested on a flat track on the campus, where the scooters were used to support environmentally friendly mobility around the campus area. This test ensured that the designed speed monitoring system was able to provide real-time data on scooter performance based on user weight, as well as support increased efficiency of battery energy use.
Protecting the Digital Ecosystem: AI's Dual Role in Machine Identity Security
Authors: Sushant Chowdhary
Published: February 2025

The convergence of artificial intelligence, machine identities, and privileged access management represents a pivotal shift in the cybersecurity landscape, introducing unprecedented challenges for modern organizations. This comprehensive analysis examines how artificial intelligence-powered threats are revolutionizing attack vectors through automated social engineering, adaptive malware, and intelligent ransomware capabilities, while simultaneously transforming defensive strategies through enhanced threat detection and human-artificial intelligence collaboration. This article explores the critical intersection of machine identity proliferation - encompassing applications, containers, and Internet of Things devices - with traditional security frameworks, highlighting the complexities of certificate management, access controls, and continuous monitoring in automated environments. Furthermore, it investigates the evolution of privileged access management as it adapts to secure both human and machine identities, addressing challenges such as artificial intelligence-augmented privilege escalation and insufficient monitoring capabilities. Special attention is given to emerging trends, including artificial intelligence-driven attack simulation, unified identity and access management solutions, and evolving regulatory requirements, providing organizations with actionable insights for developing resilient security strategies in an increasingly complex digital ecosystem.
Universal Automation Framework: Revolutionizing Test Automation Architecture
Authors: Sujeeth Manchikanti Venkata Rama
Published: February 2025

The Universal Automation Framework (UAF) represents a transformative approach to test automation that addresses the persistent challenges faced by organizations in maintaining effective testing strategies. This comprehensive article explores how UAF's tool-agnostic architecture revolutionizes test automation by introducing a standardized, maintainable, and efficient framework that adapts to evolving technology stacks. Through its innovative object repository management, virtual application modeling, and unified test case structure, UAF enables organizations to overcome traditional automation limitations while significantly improving test coverage, reducing maintenance overhead, and enhancing overall software quality. The framework's implementation demonstrates substantial benefits across multiple dimensions, including standardization, productivity, cost optimization, and quality improvements, making it particularly valuable for enterprises managing diverse technology stacks and complex testing environments.
A Review on Technologies for Group-Aware Malayalam Conversational AI
Authors: Husaima Mailanchy T K  , Suha Narghees A S  , Taniya T S  , Vishnu M S  , Dr. L.C. Manikandan
Published: February 2025

This review paper explores the foundational technologies required to develop a group-aware Conversational AI for the Malayalam-English bilingual community. The objective of the project is to create an AI system capable of interacting naturally in group settings, dynamically recognizing and responding to multiple speakers in real-time. The key components of this system include voice separation, which isolates individual speakers’ voices in noisy environments, speech-to-text (STT), which accurately transcribes Malayalam speech that may contain English phrases, and text-to-speech (TTS), which synthesizes natural-sounding speech in Malayalam-English conversational patterns. This review covers recent advancements in each of these three areas by evaluating three core papers for each technology. Through this review, we aim to understand the current capabilities of these technologies and how they can be applied to build an accessible, scalable Conversational AI that bridges the language gap for Kerala’s linguistically diverse population.
The impact of psychosocial support and psychological well-being among expatriate students
Authors: Al-Ja'afreh Somaya Abdel-Hameed , Al-krenawi Alean , Al-Habies Feras  Ali , Abudoush Ahmad Nabeel , Alourani Omar  Ismail Hamzeh
Published: February 2025

This study explores the impact of a psychological and social support program on social support and psychological security among expatriate students. Using a quasi-experimental design, 48 Arab expatriate students at Al-Isra Private University (16 males, 32 females) were assigned to experimental and control groups (24 each). Standardized scales measured social support and psychological security before and after the intervention. Results showed moderate social support and low psychological security among students prior to the program. Post-intervention, the experimental group demonstrated statistically significant improvements (p < 0.05) in both areas, highlighting the program’s effectiveness. The study emphasizes the importance of ongoing psychological security assessments to enhance expatriates' mental well-being.
Practical approaches to the diagnosis of osteoarthritis
Authors: Vovchuk P. O.
Published: February 2025

Osteoarthritis is a common chronic joint disease in dogs, characterized by the progressive development of pain, lameness, and a significant reduction in activity, which significantly impacts the quality of life of the affected animals. This disease develops gradually and can have various etiological factors, including trauma, genetic disorders, dysplasia, and obesity. Osteoarthritis is accompanied by changes in the osteochondral complex, including alterations in cartilage tissue, subchondral bone, synovial membrane, and periarticular structures. These pathological changes complicate the diagnosis of the disease and require the use of modern imaging techniques and laboratory tests. The application of contemporary diagnostic methods enhances the accuracy of osteoarthritis diagnosis and allows for detecting the disease at early stages. In particular, the Canine Osteoarthritis Staging Tool (COAST) should be noted, which includes a comprehensive approach to assessing the condition of the animal, encompassing both clinical symptoms and radiological changes. Radiography remains the primary imaging method, but its sensitivity at early stages is insufficient, limiting its use in detecting initial joint changes. Magnetic resonance imaging and computed tomography are more precise imaging methods that allow for detecting small osteophytes, subchondral changes, and other pathological processes that cannot be visualized using radiography. In addition to imaging methods, synovial fluid analysis plays a crucial role in diagnosing osteoarthritis, as it identifies inflammatory processes in the joints. Specifically, the assessment of inflammation biomarkers, such as C-reactive protein and hyaluronic acid, can be helpful in differentiating osteoarthritis from other inflammatory joint diseases. Despite significant progress in diagnosing osteoarthritis in dogs, certain limitations remain, related to the high cost and limited availability of modern imaging methods and biomarker analysis. This necessitates further research to improve early detection methods of osteoarthritis and to optimize treatment strategies, which will help improve the prognosis and quality of life for animals with this disease.
Evaluation of effectiveness and safety of therapeutic regimens for dirofilariasis in dogs
Authors: Levytska V. A. , Poliukhovych V. I.
Published: February 2025

Dirofilariasis caused by Dirofilaria immitis and Dirofilaria repens is a serious disease prevalent in dogs, posing significant health risks and potential zoonotic consequences for humans. This article investigates the effectiveness of various treatment protocols for canine dirofilariasis. The study aimed to assess the clinical efficacy and safety of different therapeutic approaches in treating dogs with varying stages of the disease. A total of 12 dogs were included, divided into two groups of six: a control group and an experimental group. The control group received standard therapy with melarsomine at a dose of 2.5 mg/kg administered twice on days 60 and 90. Additionally, dexamethasone was given before each injection to reduce the risk of thromboembolism. No other medications were used, and physical activity was restricted after injections. In the experimental group, an extended therapy regimen was applied: melarsomine was administered three times, supplemented with prednisolone, doxycycline, moxidectin, and other supportive drugs. This approach ensured comprehensive monitoring of the dogs' health. On days 60 and 91 of therapy, patients were closely monitored, with activity restricted to prevent complications. The study revealed no anaphylactic reactions to moxidectin in the experimental group, while side effects from doxycycline (vomiting, diarrhea, and anorexia) were effectively managed by adjusting the dosage. In the control group, side effects were more pronounced; diarrhea and vomiting required repeated dose adjustments and supportive therapy. Local reactions to melarsomine injections occurred in 67 % of the control group dogs, causing significant discomfort. Treatment results after four months showed that all dogs in the experimental group tested negative for microfilaria. After nine months, antigen tests confirmed the absence of infestation in all experimental group patients, demonstrating the high effectiveness of the comprehensive therapy. Although the control group also had negative antigen tests, clinical complications and frequent side effects indicated lower treatment efficacy. Thus, the findings confirmed the efficacy of the enhanced therapeutic regimen with triple melarsomine administration combined with doxycycline, providing reliable infestation control and minimizing complications.
Evaluation of the rehabilitation potential of dogs in the shelter according to the dynamics of blood indicators and physiological parameters
Authors: Tymoshenko O. P. , Sydelov V. V.
Published: February 2025

The aim of this work was to evaluate the criteria for adaptation of dogs to a two-month stay in a shelter for homeless animals. We investigated 11 clinically healthy dogs that were selected. We determined: body weight, 18 biochemical indicators in blood serum and 13 hematological tests. The animals were examined at time of arrival at the shelter and after 1 and 2 months of stay in it. In the blood samples, indicators of erythrocyte and leukocytopoiesis were determined. Based on the obtained data, 5 leukocyte indices were calculated. During admission to the shelter, it was established that some of the dogs had subclinical health disorders. The average live weight of animals (22.67 ± 2.16 kg) fluctuated within significant limits (10.0–34.2 kg). Tendency to increase body weight was observed after 2 months. It was found that at the time of admission to the shelter, a significant part of the indicators of erythro- and leukocytopoiesis exceeded the reference norms. There was a decrease in the concentration of albumin, urea, glucose, cholesterol, an increase in the level of total protein at the expense of globulins, total bilirubin, the activity of ALT, AST, GHT, alkaline phosphatase, and LDH. During the 1-month stay in the shelter, not all of the specified criteria reach the values of the relevant norms. After 2 months, there is a complete recovery of the health of the dogs according to clinical and physiological parameters, as well as according to blood parameters. In general, there is a positive dynamic of biochemical tests after 2 months of the animals staying in the shelter: on the day of arrival of the dogs, 72.2 % deviations of biochemical indicators from normal values were recorded, after 1 month of keeping the animals in the shelter – 22.2 %, after 2 months of keeping – 5.55 %. This term can be considered sufficient to realize the rehabilitation potential of dogs. The results obtained in this study should be implemented in the practical activities of shelters for animals in order to objectively assess the state of their health, based on scientifically based terms of stay of animals in shelters and the length of time for their full functional adaptation.
Izatizone in veterinary medicine and medicine
Authors: Lisniak O. I. , Gutyj B. V. , Kordys B. D. , Fedin R. M. , Zastryzhna M. L. , Yaremchuk T. P. , Semiion-Lutsyshyn O. V. , Loziuk L. V. , Loziuk R. M. , Lisniak T. O.
Published: February 2025

This scientific work is devoted to a comprehensive analysis of the results of the use of izatizone in combination with the microwave therapy method for the treatment of viral diseases in medicine and veterinary medicine. Viral infections remain one of the most pressing medical problems of our time, and the search for effective methods of prevention and treatment remains a high-priority task. The growing need to strengthen the fight against infectious diseases encourages us to expand the arsenal of antiviral agents and study the mechanisms of their action. The development of structurally profiled preparations and the study of molecular recognition between three-dimensional structures have become an integral part of the modern search for drugs. The work presents the results of a study in which the antiviral effect of izatizone and the microwave therapy method in combination was studied. The effect of this combination on different types of viruses and different categories of patients was studied. The results of the analysis confirmed the effectiveness of izatizone in the treatment of viral diseases and also showed that its combination with the method of microwave therapy contributes to a decrease in the duration of the disease and an improvement in clinical indicators. The results obtained may be of great importance for the further development of methods for the treatment of viral infections. They indicate the prospects of a combined approach to treatment based on the use of antiviral drugs and new methods of physiotherapy. These results can be used for further scientific research and the development of new methods for the treatment of viral infections in medicine and veterinary medicine.
Prediction of biological activity of 4-(3,4 dimethoxybenzylidene)amino)-5-(2-fluorophenyl)-4H-1,2,4 triazole-3-thiol
Authors: Martynyshyn V. P. , Hunchak V. M. , Gutyj B. V. , Rudenko O. P.
Published: February 2025

Among the various heterocyclic systems, 1,2,4-triazole derivatives occupy a leading position due to a whole range of unique and valuable properties. 1,2,4-triazole derivatives exhibit a wide range of pharmacological activity, affecting various biochemical processes while having minimal toxicity. Due to their unique chemical structure, these heterocyclic compounds exhibit different biological properties, making them promising for developing new drugs. The work aimed to study new types of activity of 4-(3,4-dimethoxybenzylidene)amino)-5-(2-fluorophenyl)-4Н-1,2,4-triazole-3-thiol using in silico methods, which will allow to expand the avenues of scientific research and establish a promising direction for further testing for this compound. Virtual screening of the compound was performed using the free online service SwissTargetPrediction. Molecular docking was performed using Autodock 4.2.6. Results were visualized using Schrödinger Release 2018-1: Schrödinger, LLC, New York, NY, 2018. ADME assessment was performed using the free SwissADME tool. Analysis of the results of the computer screening demonstrates a promising search for inhibitors of alkaline phosphatase, histidine kinase, phosphodiesterase, anti-inflammatory, antiviral, antitumor, and antifungal activity in 4-(3,4-dimethoxybenzylidene)amino)-5-(2-fluorophenyl)-4H-1,2,4-triazole-3-thiol. The structure of the most active inhibitor in its most probable docked conformation is complementary, which is explained by the presence of a structural element – the 1,2,4-triazole ring. Due to its physical properties, pharmacokinetics, and drug similarity indicators, the selected compound is a promising object for developing a new medicinal substance with antifungal properties.
Comparison of the Performance of the C.45 Algorithm with Naive Bayes in Analyzing Book Borrowing at the Library Pringsewu Muhammadiyah University
Authors: Wilian Dani , Sriyanto Sriyanto
Published: February 2025

This study examines the effectiveness of the Naïve Bayes and C4.5 algorithms in analyzing book borrowing patterns at the Pringsewu Muhammadiyah University Library. As libraries increasingly serve as vital educational hubs, understanding user borrowing behavior is essential for effective collection management and service enhancement. The research follows the Cross-Industry Standard Process for Data Mining (CRISP-DM), which includes stages of business understanding, data understanding, preparation, modeling, evaluation, and implementation. A dataset consisting of 5,586 records and ten attributes related to book lending was utilized, with comprehensive data cleaning and preprocessing conducted. The performance of both algorithms was assessed using K-fold cross-validation, yielding an accuracy of 96.26% for C4.5, compared to 91.44% for Naïve Bayes. These results demonstrate that C4.5 is more adept at capturing complex relationships within the data, providing deeper insights into user preferences and enhancing library services. This research underscores the potential of data mining techniques to optimize library management and proposes avenues for future investigation, such as exploring advanced machine learning algorithms and expanding datasets for use in broader library contexts.
Weather Monitoring and Classification Tools Using Fuzzy Logic Method Based on Internet of Things for Agriculture
Authors: Avindra Muhammad Alfazri , Taqwa Ahmad , Suroso
Published: February 2025

Agriculture is a crucial sector that faces significant challenges due to climate change, such as altered rainfall patterns, increased temperatures, and extreme weather, which threaten productivity. This research aims to design and develop a weather monitoring and classification tool utilizing the Fuzzy Logic method based on the Internet of Things (IoT). The system integrates sensors for temperature, humidity, air pressure, wind speed, and rainfall, processing the data through Fuzzy Logic to classify weather into sunny, cloudy, light rain, moderate rain, and heavy rain. The results are accessible in real-time via an LCD screen and the Blynk application. Achieving 100% accuracy in monitored conditions, the system operates continuously for 24 hours, powered by solar energy. Unlike traditional systems, this tool provides innovative solutions to weather-related agricultural challenges, enabling farmers to make informed decisions and mitigate losses due to extreme weather. This research contributes to advancing IoT applications in precision agriculture, providing a reliable, sustainable, and scalable solution to weather monitoring.
KMS Protoype using Stohmaier Framework at Association of Indonesian Kindergarten Teachers in South Bangka Regency
Authors: Sulaiman Rahmat , Agustina Mardeka Raya
Published: February 2025

IGTKI is a kindergarten teacher association organization that aims to realize the quality of early childhood education with a spirit of professional love and character to be able to face the era of globalization. However, this goal is not fully implemented because of the distance of each school is far, the results of the training are not socialized, the lack of knowledge to handle students with special needs so that the lack of knowledge sharing among PAUD teachers. To increase the knowledge sharing needed a Knowledge Management System application that can be a solution of knowledge sharing that is not hindered by the limitations of time and place. This study uses the Strohmaier Framework for modeling knowledge management systems. Techniques of Analysis and system design are carried out using the object oriented approach method Unifed Manipulation Language (UML). The suitability of the system to the business process was tested using the Forum Group Discussion (FGD) method which was validated using the Fit criteria from Strohmaier's theory which produced a value of 76%, this value shows that the Knowledge Infrastructure designed is in accordance with the business process. Meanwhile, user acceptance of the system was tested using User Acceptance Testing (UAT) in the form of a questionnaire which was calculated based on the Linkert scale, producing a value of 84%. From this value it can be concluded that the level of user acceptance at IGTKI is good for the KMS created.
COMPREHENSIVE EXPLORATION OF VESSEL CONFIGURATION AND NANOPARTICLE INFLUENCE ON THERMAL AND ENERGETIC BEHAVIOR IN LAMINAR FLOW AGITATION
Authors:   Laboratory of Applied Mechanics, Faculty of Mechanical Engineering, University of Science and Technology of Oran, Nekrouf Abderrahim Sidi Mohammed , Youcefi Sarra ,   Department of Mechanical Engineering, Faculty of Mechanical Engineering, University of Science and Technology of Oran, Laidoudi Houssem ,   Laboratory of Sciences and Marine Engineering, University of Science and Technology of Oran, Mokhefi Abderrahim ,   Mechanics, Modeling and Experimentation Laboratory L2ME, Faculty of Sciences and  Technology
Published: February 2025

The research focuses on the significance of heat transfer in a stirred tank, a necessary aspect for various industrial applications. This process directly influences the kinetics of chemical reactions, the quality of mixtures, and the overall productivity of industrial processes. Efficient heat transfer optimizes reaction conditions, ensures thermal uniformity in the tank, and enhances the productivity of mixing operations. The main objective of this study is to analyze the impact of the shape of the stirred tank, combined with the addition of nanoparticles in an anchor-type stirred tank, on the hydrodynamic, thermal, and energy performance of a nanofluid. The tank wall is maintained at a high temperature, while the agitator is considered adiabatic. At the initial moment, the nanofluid has a cold temperature. The equations of motion, continuity, and energy for a non-stationary two-dimensional laminar flow were solved using the finite element method. Simulation results indicate that adding nanoparticles to the base fluid leads to a significant improvement in heat transfer in the stirred tank compared to the base fluid. Furthermore, a decrease in heat transfer is observed with the square shape of the tank. It is also noted that the provided agitation power is higher with a larger volumetric fraction of nanoparticles. A remarkable reduction in energy consumption with the variation of shape has been observed. These findings emphasize the importance of carefully selecting the tank shape and volumetric fraction of nanoparticles to optimize heat transfer while minimizing energy consumption
STUDY OF ALUMINUM EXTRACTION AND IRON REMOVAL FROM KAOLIN CLAYS USING TWO-STAGE TREATMENT WITH SULPHURIC ACID
Authors:   M.Nagiev Institute of Catalysis and Inorganic Chemistry, Ministry of Science and Education  of the Republic of Azerbaijan, Heydarov A.A.
Published: February 2025

This paper presents the results of research on the treatment of kaolin clay with sulfuric acid of various concentrations. The goal of the initial stage of research was to determine the optimal conditions affecting the iron removal process. The degree of extraction of Fe, Al, Si in solution was determined from solid samples obtained during the leaching process using X-ray phase analysis (XRD), IR spectroscopy, thermal, and also from the results of EDS analyses. The results show that processing clay with a 5% solution of sulfuric acid in an autoclave at a temperature of 125-130º C, at a pressure of 4-5 atm, for 0.5-1.0 hours, or at a temperature of 85-90º C, for 5 hours purifies iron up to 96-99%. Kaolin clay separated from iron was mixed with 95% sulfuric acid and thermally treated at a temperature of 250º C for 2 days, after which the sulfated mass was dissolved in water at a temperature of 80-90º C in the ratio S:L = 1:5. The resulting mixture was filtered and the sulfate solution was evaporated to a density of 1.4-1.5 g/sm3. In this case, pure salt Al2(SO4)3∙nH2O precipitates in the crystallizer
REACTIVITY OF METAL COMPLEXES WITH RADICALS
Authors:   M.Nagiev Institute of Catalysis and Inorganic Chemistry, Ministry of Science and Education  of the Republic of Azerbaijan, Medjidov A.A. , Ismayilov R.H. ,   M.Nagiev Institute of Catalysis and Inorganic Chemistry, Ministry of Science and Education  of the Republic of Azerbaijan, Fatullayeva P.A. ,   M.Nagiev Institute of Catalysis and Inorganic Chemistry, Ministry of Science and Education  of the Republic of Azerbaijan, Tagiyev D.B. ,   M.Nagiev Institute of Catalysis and Inorganic Chemistry, Ministry of Science and Education  of the Republic of Azerbaijan
Published: February 2025

This review presents the results of studies on the reactivity of metal complexes with short-lived radicals (primarily peroxyl radicals) and metal complexes (mainly Cu(II) ions) with chelating nitroxide radicals. The reactions of newly synthesized paramagnetic ligands – Schiff bases derived from ortho-hydroxyaromatic aldehydes and two nitroxide radicals, 2,2,5,5-tetramethyl-3-amino-pyrrolidine-1-oxide and 2,2,6,6-tetramethyl-piperidine-4-amino-1-oxide – are discussed. It has been shown that in the derivative of the five-membered pyrrolidine radical, the radical center becomes part of the coordination sphere of the Cu(II) ion and is reduced to hydroxylamine. Ultimately, this leads to the formation of binuclear complexes with strong antiferromagnetic interactions between the Cu(II) ions. At room temperature, the resulting binuclear complexes interact with chloroform to abstract HCl and, with pyridine in the presence of oxygen, form paramagnetic mononuclear Cu(II) complexes. Separate sections of the review are devoted to catalytic oxidation reactions of alcohols and other substrates using metal complexes with nitroxide radicals (mainly TEMPO) as catalysts. Additionally, the catalytic reactions of metal complexes with phenoxyl radicals, which serve as biochemical models of the enzyme galactose oxidase, are discussed
OXIDATION OF n-HEXANE WITH OXYGEN IN THE PRESENCE OF A SOLID-PHASE CATALYST Ni-IMMOBILIZED POLY-4-VINYLPYRIDINE
Authors:   M.Nagiev Institute of Catalysis and Inorganic Chemistry, Ministry of Science and Education  of the Republic of Azerbaijan, Isazade A.F. , Mammadova U.A. ,   M.Nagiev Institute of Catalysis and Inorganic Chemistry, Ministry of Science and Education  of the Republic of Azerbaijan, Asadov M.M. ,   M.Nagiev Institute of Catalysis and Inorganic Chemistry, Ministry of Science and Education  of the Republic of Azerbaijan, Zeynalov N.A. ,   M.Nagiev Institute of Catalysis and Inorganic Chemistry, Ministry of Science and Education  of the Republic of Azerbaijan, Tagyiev D.B. ,   M.Nagiev Institute of Catalysis and Inorganic Chemistry, Ministry of Science and Education  of the Republic of Azerbaijan
Published: February 2025

Ni-containing catalysts based on immobilized poly-4-vinylpyridine were prepared. Samples of catalysts with 2, 5, 10 wt.% Ni(II) were tested in the process of n-hexane oxidation. The studies were carried out in the temperature range 313 - 383 K, hexane: oxygen molar ratio = 1:3.38 and atmospheric pressure. The identification of products from the oxyfunctionalization of n -hexane was analyzed by chromatographic analysis (Agilent 7890B). The results of using Ni-containing catalysts on the immobilized polymer poly-4-vinylpyridine were compared with our previous results using manganese-containing catalysts. It has been established that the selectivity and activity of the nickel catalyst for the oxidation of n-hexane is somewhat lower than that of the manganese catalyst immobilized on poly-4-vinylpyridine. The nature of chemical bonds, structure and elemental composition of the samples were determined using the methods of Fourier transform infrared (IR) spectroscopy (FTIR), X-ray phase analysis (D2-Phaser “Bruker” diffractometer)
DEVELOPMENT OF THE COMBINED METHOD OF EXTRACTION, PURIFICATION AND ANALYTICAL HPLC PROCEDURES FOR OBTAINING THREE MAJOR TRITERPENE ACIDS FROM ALMOND HULLS
Authors:   Petre Melikishvili Institute of Physical and Organic Chemistry at Ivane Javakhishvili Tbilisi State University, Rubashvili I. , Tsitsagi M. ,   Petre Melikishvili Institute of Physical and Organic Chemistry at Ivane Javakhishvili Tbilisi State University, Chkhaidze M. ,   Petre Melikishvili Institute of Physical and Organic Chemistry at Ivane Javakhishvili Tbilisi State University, Ebralidze K. ,   Petre Melikishvili Institute of Physical and Organic Chemistry at Ivane Javakhishvili Tbilisi State University, Zautashvili M. ,   Petre Melikishvili Institute of Physical and Organic Chemistry at Ivane Javakhishvili Tbilisi State University, Khachidze M. ,   Petre Melikishvili Institute of Physical and Organic Chemistry at Ivane Javakhishvili Tbilisi State University
Published: February 2025

Almond hulls represent a low-cost and rich source of fruit-derived bioactive compounds with the potential of being processed for its multifunctional clinical, nutritional, and pharmaceutical value. The pentacyclic triterpenoids - ursolic acid (UA), oleanolic acid (OA) and betulinic acid (BA) are particularly abundant in almond hulls and have attracted a lot of attention due to their unique and strong pharmacological activities. The aim of this study was to develop an alternative, selective, reproducible, low-cost, robust and high-yield extraction-based method by ultrasound-assisted technique combined with a rapid, effective and specific analytical HPLC procedure for obtaining three major triterpene acids – ursolic, oleanolic and betulinic acids from almond hulls as a waste material in agriculture and their quantitative determination in the obtained extracted product and almond hulls as well. The three-stage sequential ultrasound-assisted extraction was carried out under ultrasonication at 40 kHz. A dried powdered extracted product was obtained after the stepwise extraction process with a high yield 0.2-0.3%. The HPLC analysis was performed using a column - C18 4.6×250 mm, 5 μm with an isocratic elution of mobile phase and detection at 205 nm to quantitatively determine the assay of each analyte in the obtained extracted product and the waste material. The proposed method was validated with respect to the following method performance characteristics: system suitability test, specificity, precision, linearity-range, sensitivity, limits of quantification and detection, accuracy and robustness. The average recovery of the combined method is >93%. The average content of ursolic acid, oleanolic acid and betulinic acid equals to 0.891 mg, 0.697 mg and 1.014 mg per 1 g of the almond hulls, respectively. The purity of the dried extracted product is not less than 92%
ДОСЛІДЖЕННЯ РОБОЧОГО ПРОЦЕСУ РОБОТИ ВІЛЬНОВИХРОВОГО НАСОСА З НЕЦИКЛІЧНИМ РОБОЧИМ КОЛЕСОМ У РОБОЧОМУ ДІАПАЗОНІ
Authors: Кондусь В. Ю. , Кругляк А. А. , Бага В. М. , Думанчук М. Ю.
Published: February 2025

Вільновихрові (TFP) насоси широко застосовуються в різних галузях промисловості для перекачування забруднених, волокнистих або газовмістних рідин завдяки їх простій конструкції, надійності та низькому ризику засмічення, незважаючи на обмеження ефективності та напору. Основними недоліками вільновихрових насосів є низька енергоефективність (ККД насоса η=0,38-0,58) і можливість засмічення їх проточної частини продуктом, що перекачується. Зазначена проблема може бути вирішена шляхом забезпечення ефекту самоочищення вільновихрового насоса за допомогою проєктування робочого колеса з нерівномірним розташуванням лопатей, яке забезпечить пульсаційний характер тиску в його міжлопатевих каналах. Метою дослідження було встановлення характеристик насоса з нерівномірно розташованими лопатями та порівняння отриманих результатів із характеристиками аналогічного насоса з рівномірно розташованими лопатями. Для проведення чисельного дослідження у програмному пакеті ICEM CFD були створені неструктуровані розрахункові сітки статорного елементу (корпус) та роторного елементу (робоче колесо). Моделювання робочого процесу насоса виконувалося у стаціонарній постановці з використанням програмного комплексу Ansys CFX, причому була використана k-ε модель турбулентності у стаціонарній постановці, в якості робочого середовища використовувалася вода за температури 25°С. За результатами дослідження встановлено, що при використанні робочого колеса з нециклічним розташуванням лопатей (з відсутніми лопатями) відбувається збільшення відносної швидкості біля робочої сторони лопаті в розширеному міжлопатевому каналі, нерівномірний розподіл швидкості на вході в колесо одночасно з появою зони відриву потоку в міжлопатевих каналах, що призводить до збільшення втрат, зменшення тиску і, відповідно, ККД насоса. У той же час вищевикладене дозволяє стверджувати, що згідно із законом Бернуллі в розширених каналах робочого колеса з нециклічним розташуванням лопатей в зонах зниженої швидкості існує деякий підвищений тиск. Саме такий підвищений тиск створює передумови для нестійкого відносного руху робочої рідини в порівнянні з використанням стандартного робочого колеса. У свою чергу, цей механізм може бути використаний як механізм самоочищення для вільновихрових насосів.
КОМП’ЮТЕРНЕ МОДЕЛЮВАННЯ БАЗОВИХ КОНСТРУКЦІЙНО-ЕКСПЛУАТАЦІЙНИХ ГЕОМЕТРИЧНИХ ПАРАМЕТРІВ ДВОДИСКОВИХ СОШНИКІВ
Authors: Воробйов О. М.
Published: February 2025

У нинішній складний воєнний час для України питання підвищення ефективності сільськогосподарського виробництва становить актуальну державну та наукову прикладну проблему. Один із шляхів її вирішення полягає в подальшому вдосконаленні різноманітних застосовуваних технічних засобів, зокрема для обробітку ґрунту перед посівом та за умови одночасної сівби. На теперішньому етапі розвитку серед них доволі перспективні дискові знаряддя. У порівнянні з полицевими їхньою головною перевагою є суттєво менші енергетичні витрати при виконанні багатьох агротехнічних процесів. Також дискові робочі органи сприяють збереженню належної структури ґрунту, краще відповідають екологічним вимогам. Мета даної публікації полягає у викладенні запропонованого математичного апарату, який спрямований на забезпечення ефективної комп’ютерної дефініції раціональних варіантів дводискових сошників. Останнє реалізується завдяки докладно поданим і проаналізованим аналітичним залежностям між базовими геометричними конструкційно-експлуатаційними параметрами зазначених виробів. Це стосується діаметрів дисків, їхнього відхилення від вертикалі, кутів повороту в горизонтальній площині, положення точок сходження, глибини обробітку ґрунту та характеру отримуваних при цьому профілів борозни. Наведений математичний апарат і проілюстровані відповідні прийоми геометричного моделювання сприяють не тільки підвищенню точності різноманітних розрахунків, наприклад, землеробської механіки, а й дозволяють надалі покращувати якість та продуктивність автоматизованого проєктування розглянутих сільськогосподарських знарядь, зокрема, засобами структурно-параметричного формоутворення. Це здійснюється на основі варіантного комп’ютерного конструювання, що спирається на вказану методологію. Її напрацьовано науковою школою прикладної геометрії Національного технічного університету України «Київський політехнічний інститут імені Ігоря Сікорського» й апробовано у вітчизняній авіаційній галузі. Поширення акцентованого підходу на засоби механізації сільськогосподарського виробництва сприятиме подальшому вдосконаленню як існуючих теоретичних положень, так і наявної практики. Окреслена тематика становить, на думку автора, відповідний перспективний напрямок проведення належних прикладних наукових досліджень.
Strategic planning with a production chain approach to identify training needs in the agrifood sector
Authors: Uzcanga Pérez Nelda Guadalupe , Maya Martínez Aixchel , Sánchez Toledano Blanca , Cano González Alejandro
Published: February 2025

Objective: to generate a strategic plan, with a production chain approach, that allows identifying the training needs in the agrifood sector in Quintana Roo.
Design/ Methodology/ Approach: the study was developed in three methodological stages 1) A workshop to explore the training needs through participatory action, in order to obtain a relational framework of those institutions in the sector in which the trainees interact, aiming to identify and prioritize the training needs in a double-entry matrix; 2) Design of the training program, using as input the needs identified in the exploratory workshop; 3) Implementation of the training, with an ex ante and ex post evaluation of each topic to verify that the training was effective.
Results: the main problems detected were marketing (28.8%), production (25.9%), supply of inputs and services (25.3%), transformation (12.2%), and consumption (7.1%). Likewise, a relational framework of 25 institutions that provide support to the different links identified in the production chain. The median of achievement (correct scores) before training was 8.92, and 10.81afterwards.
Limitations/ Implications of the study: the capacity of the course was limited by the available resources, both facilities and financial. However, it is important to implement a mixed modality to reach a greater number of people.
Findings/ Conclusions: strategic planning with a production chain approach is a useful tool to focus ad hoc training needs, since 70.9% of professionals improved their skills on crops of interest.
How are communication companies adopting AI
Authors: Tejedor Calvo Santiago , Vick Saurí Stephanie , Cervi Laura
Published: February 2025

Artificial intelligence (AI) is reshaping the media landscape, influencing news production, consumption, and dissemination. AI algorithms support content generation, trend tracking, and fact-checking. This study examines 108 companies using AI through a documentary review and expert survey. Text generation is the most common function, while experts consider fact-checking the most useful. A geographic disparity exists, with the United States leading in AI adoption, while other regions lag. AI holds great potential for media transformation, but its inclusion remains uneven across countries.
Đặc điểm giấc ngủ ở trẻ động kinh từ 1 đến 36 tháng tuổi
Authors: Lê Thị Thu Hường , Nguyễn An Nghĩa
Published: February 2025

Đặt vấn đề: Các vấn đề về giấc ngủ xảy ra khá phổ biến ở trẻ động kinh. Tuy nhiên tại Việt Nam, các nghiên cứu về giấc ngủ ở trẻ động kinh còn rất hạn chế.

Mục tiêu: Mô tả đặc điểm giấc ngủ và xác định yếu tố liên quan đến các vấn đề về giấc ngủ ở trẻ động kinh.

Đối tượng và phương pháp nghiên cứu: Nghiên cứu mô tả 68 trẻ từ 1 - 36 tháng tuổi tại bệnh viện Nhi Đồng 1, sử dụng bộ công cụ Brief Infant Sleep Questionnaire (BISQ).

Kết quả: Phần lớn trẻ ngủ chung phòng (89,7%) và chung giường (85,3%) với cha mẹ. Các thói quen vào giấc ngủ thường gặp là bú mẹ/bú bình/ăn nhẹ (89,7%), chơi đùa tại chỗ (79,4%), nghe nhạc (38,2%). Tổng thời gian ngủ trung bình trong 24 giờ là 13,10 ± 2,47 giờ. 50% trẻ gặp các vấn đề về giấc ngủ, cơn động kinh xảy ra trong 2 tuần gần nhất có liên quan đến sự xuất hiện các vấn đề về giấc ngủ (p = 0,03).

Kết luận: Các vấn đề về giấc ngủ xảy ra khá phổ biến ở trẻ động kinh, việc hiểu về đặc điểm giấc ngủ và yếu tố ảnh hưởng đến giấc ngủ là một phần cần thiết trong chăm sóc toàn diện ở trẻ động kinh.

Từ khóa: trẻ em; động kinh; đặc điểm giấc ngủ; các vấn đề về giấc ngủ; BISQ