bluuebunny/crossref_metadata_2025 huggingface dataset:
Effectiveness of English language teaching methods and language learning skills among college students in public higher education institutions in Sulu
Authors: Sarabi Alnakier A. , Ututalum Charisma S.
Published: July 2024

English is the most widely spoken language in the world, serving as a common medium for people from different linguistic backgrounds. It is the primary or secondary language in many countries and is often used as the international language of business, diplomacy, science, and technology. Hence, there was a need for effective teaching and instructional strategy to enhance the competence of the college students. This study investigated the effectiveness of various English language teaching methods and assessed the language learning skills of college students in public higher education institutions (HEIs) in Sulu, Philippines. Quota sampling (n=200) was carried out to sample the college students from four (4) different public HEIs in Sulu. Close-ended questionnaires were administered to determine the effectiveness of three different English language teaching methods—(i) Grammar-Translation Method, (ii) Direct Method, and (iii) Audio-Lingual Method. This study also analyzed the level of English language learning competence of college students based on their (i) listening skills, (ii) speaking skills, (iii) reading skills, and (iv) writing skills. Key findings indicated that different teaching methods, namely the Grammar-Translation Method, the Direct Method, and the Audio-Lingual Method, each offered distinct advantages for language learning. In assessing the language learning skills of the students, the study found high competence across all four key areas: listening, speaking, reading, and writing. Inferential analysis indicated that the effectiveness of English language teaching methods can be correlated to the language competence of college students. Further studies shall be done to determine whether the teaching methods could directly influence the language skills of students.
Understanding word problems: Pre-service math teacher proficiency
Authors: ALALI Rommel , Wardat Yousef , Helali Mamdouh , Alshraifin Nermien
Published: July 2024

Mathematics holds a pivotal role in education, empowering students to apply mathematical principles across various domains. This study investigates the proficiency of 100 pre-service mathematics teachers enrolled in a Bachelor of Science with Education (Mathematics) Honors program at Yarmouk University in identifying content and context within mathematical word problems. Employing a case study approach and utilizing the Mathematics Word Problems Test and the Content and Context Questionnaire, the research underscores challenges in error detection and content comprehension. Pre-service mathematics teachers exhibited difficulties recognizing inaccuracies, emphasizing the importance of integrating practical context and enhancing critical thinking in pre-service teacher education. This study advocates for further research to develop strategies addressing these challenges and fostering a more holistic approach to mathematical problem-solving.
Benedicto XIII y las posibilidades eclesiásticas de la gobernación de Orihuela: poder religioso y diplomacia pontificia en la Europa mediterránea (1394-1423)
Authors: Cañizares Gómez María José
Published: July 2024

El siglo XV comenzó en un momento de plena inestabilidad eclesiástica, con un cisma cada vez más enquistado y unas posiciones muy enfrentadas por parte de los distintos bandos. Benedicto XIII, papa de Aviñón, veía progresivamente mermar su autoridad y la fidelidad de la Corona de Aragón se convirtió en su baza más importante para mantenerse en el poder. El gran acercamiento al pontificado de la monarquía aragonesa se presentó para el territorio de Orihuela como una oportunidad para resolver su pleito eclesiástico con la Diócesis de Cartagena, pero el devenir de los acontecimientos que azotaron la Europa de aquellos años no se lo pondrían nada fácil.
La ciudad de la desigualdad económica. Evolución de la distribución de la riqueza en Ciutat de Mallorca entre 1446 y 1533
Authors: Tudela Villalonga Lluís , Pascual Ramos Eduardo
Published: July 2024

Los últimos estudios sobre la riqueza de las principales ciudades trascienden el ámbito puramente económico y se centran en conocer la distribución de la desigualdad entre su población y examinar la evolución histórica del poder adquisitivo de determinadas poblaciones mediante fuentes documentales fiscales. El presente artículo tiene el objeto de analizar la desigualdad económica de los contribuyentes de la ciudad de Palma-Ciutat de Mallorca en el tránsito de la Edad Media a la Moderna (1446-1533) mediante la fuente fiscal de las tallas. Para ello se plantea, en forma de introducción, la evolución histórica de Ciutat de Mallorca en su tránsito a la Edad Moderna y la metodología empleada para conocer la distribución de la riqueza. La interpretación de los resultados económicos analizados cierra el artículo.
La importancia de la institucion de la bailía en la vida de los mudéjares del reino de Valencia en la primera mitad del siglo XV
Authors: Belenguer Tarín María Victoria
Published: July 2024

Este trabajo tiene como objetivo conocer la importancia que la institución de la Bailía General del Reino de Valencia ejerció, como máxima autoridad, sobre los mudéjares, para lo cual se ha realizado un examen exhaustivo del archivo de Bailía de 1424. La investigación archivística ha resultado la pieza clave de todo el proceso, llevado a cabo mediante un procedimiento sistemático que se inició con la lectura de todos los documentos que componían dicho registro, acompañado de la regesta de los mismos y transcripción de aquellos documentos más significativos para, a partir de su análisis e interpretación, describir y determinar dicha autoridad. Este enfoque ha permitido realizar el análisis «documento a documento» y, por tanto, estar en condiciones de formar una imagen completa de las competencias y funciones asignadas que quedaron reflejadas como la expresión de las distintas actuaciones de la Bailía General, lo cual se transformó en el eje del trabajo aquí presentado, ya que ayudó a dar respuesta al planteamiento inicial de la cuestión. Tomando como base la información aportada por el archivo y con el apoyo bibliográfico sobre la institución de la Bailía y la vida de los mudéjares en el siglo XV, se ha elaborado una aproximación a la jurisdicción que el baile general poseía sobre los mudéjares al ser considerados como parte del Real Patrimonio.
LUGARES DE LA HISTORIA DE LA EDUCACIÓN HONDUREÑA Y PARAGUAYA
Authors: García Laínez Andrés Eduardo , Elías Rodolfo , Morales-Ulloa Ricardo
Published: July 2024

¿Existe una producción historiográfica de la educación en Honduras y Paraguay? ¿Cuáles son sus vehículos de divulgación? ¿A qué intenciones, políticas y contextos obedecen? ¿Qué tipo de historia de la educación es la que se produce? Son algunas de las preguntas que intenta responder este artículo al describir los lugares que ocupan las construcciones discursivas de la historia de la educación hondureña y paraguaya en obras del campo de las ciencias sociales, específicamente de sociología, lingüística e historia, destacando las obras que son propias del campo de la historia de la educación. El resultado de este ejercicio dio visibilidad no apenas a las recurrencias de este tipo de construcción histórica de la educación en ambos países, sino, también, a la materialidad de los objetos consultados vinculada a su contexto histórico-político, ofreciendo, así, elementos de inteligibilidad para comprender la dispersa producción del campo en tales países. El artículo finaliza mostrando los esfuerzos recientes para la constitución del campo de la historia de la educación así como la importancia de invertir en el estudio historiográfico de artículos académicos y memorias de eventos nacionales e internacionales ya sea desde la vía académica – oficial, como lo es el caso de la Dirección de Historia y Patrimonio (DIHIPA), órgano de la Secretaría de Educación de Honduras; o la vía Académica – Universitaria, como lo es el caso de Paraguay con la conformación de su Sociedad de Historia de la Educación Paraguaya que organizará el XV Congreso Iberoamericano de Historia de la Educación (CIHELA) en 2023.
LA INVESTIGACIÓN SOBRE LA HISTORIA DE LA ENSEÑANZA SECUNDARIA: CONSIDERACIONES A PARTIR DE LOS CASOS DE COLOMBIA, BRASIL Y ARGENTINA
Authors: Saldarriaga Oscar de Jesús , Durán Sánchez María Fernanda , De Souza Chaloba Rosa Fátima , Acosta Felicitas
Published: July 2024

El artículo presenta un panorama sobre la investigación de la historia de la enseñanza secundaria en tres países de la región latinoamericana: Colombia, Brasil y Argentina. Se propone analizar la forma de circulación de la investigación sobre el tema a partir del relevamiento de las Memorias del Congreso Iberoamericano de Historia de la educación (CIHELA). Según los casos se consideran otras fuentes de relevancia para la cuestión. El análisis preliminar indica una tendencia general hacia la historia institucional al tratar la enseñanza secundaria, marcadas diferencias en los países en el grado de consolidación del objeto de estudio y los equipos de investigación y una ausencia de una perspectiva comparada que fortalecería su desarrollo.
A review of soil analysis and classification to improve crops in agriculture using machine learning algorithm
Authors: V.S Manjula ,   Department of Computer Science, Kampala International University, Kampala, Uganda, Marega Fatou ,   Research Student, Master of Science and Information System, Kampala International University, Kampala, Uganda
Published: July 2024

One of the most crucial aspects of our society is agriculture. For agriculture to be successful, soil is essential. Each type of soil has a unique composition. These chemical properties of the soil have an impact on crop growth. It is important to choose the right crop for that specific type of soil. Machine learning algorithms are able to classify the data from the soil series. to predict which crops are best suited to the soil type and climate of a certain area, the findings of this categorization can also be paired with crop datasets. Both the crop and the soil datasets are used. The files include geographical and chemical characteristics of soil and crop features. The classification of soil series data and the prediction of appropriate crops can be done using algorithms like SVM and the assembling approach. For this study, 15 villages in the near area of Kampala, Uganda, provided 1200 soil samples with chemical, physical, and biological characteristics. Overall, the Random Forest model produced results with 99% accuracy for cellulose enzyme activity and 94% accuracy for N-acetyl-glucosaminidase enzyme activity. Based on evaluation performance parameters and the best performance accuracy algorithms, recommendations for crops have been made.
Utilizing Support Vector Machine (SVM) to predict relative humidity in selected Ugandan cities
Authors: Nkpordee Lekia ,   Department of Mathematics and Statistics, Kampala International University, Kansanga,  Kampala, Uganda, East Africa, Osayomore Ikpotokin ,   Department of Mathematics and Statistics, Kampala International University, Kansanga,  Kampala, Uganda, East Africa
Published: July 2024

This study focuses on implementing a Support Vector Machine (SVM) model to predict relative humidity (RH) in selected cities of Uganda, addressing the critical gap in tailored predictive models for Uganda's unique climatic conditions. Leveraging three years of monthly RH data from the Uganda National Meteorological Authority, the SVM model demonstrates significant nonlinearity in RH data. Results reveal varying performance across different towns and times, with higher accuracy observed in training data (58%) compared to testing data (33%). Kampala and Arua exhibit the highest RH, with better prediction performance. The study underscores the potential of SVM for RH prediction in Uganda, offering valuable insights for sectors such as agriculture, health, and urban planning. Challenges in generalizing model performance to unseen data are noted, suggesting avenues for future research to enhance model robustness and applicability in the Uganda's context.
Determinants of time to seeking treatment among under-five children suffering from Pneumonia in Uganda
Authors: Bayowa Teniola Babalola ,   Department of Mathematics and Statistics, School of Mathematics and Computing, Kampala International University, Uganda, Mangeni Martin ,   Department of Mathematics and Statistics, School of Mathematics and Computing, Kampala International University, Uganda
Published: July 2024

The major goal of this study was to determine the factors influencing the time to seeking treatment among under-five children suffering from pneumonia in Uganda. The Makerere University School of Public Health dataset, which included 791 caregivers that were subjected to a prospective cohort study. A multi-stage sample approach was used. Descriptive statistics and Kaplan-Meier were adopted in the study. The length of time that caregivers waited before search of treatment was different among areas of Uganda. Caretakers with high wealth scores, those who frequently visited public health facilities, and those with higher monthly incomes were more likely to search for medication for their children early on. The results showed that parents of male children were more inclined to put off obtaining medical attention. The type of facility, the child's gender, the asset score, and the monthly income of the homestead were among the variables associated with time to seeking treatment among children of under-five. There is need to increase awareness of pneumonia symptoms in children. There should be increased health literacy among caretakers in the country, particularly those with lower wealth scores and monthly incomes.
Dampak Kenaikan BBM Tahun 2022 Terhadap Pedagang Sembako di Pasar Besar Palangka Raya
Authors: Intan Permatasari Hildha , Muhammad Noor Sayuti  , Akhmad Jaki
Published: July 2024

Abstract
The unavoidable increase in prices of various commodities is one of the impacts of the increase in transportation costs which of course follows developments in fuel price increases. This research aims to examine the impact of government intervention in increasing fuel prices on the increase in basic food prices in traditional markets, especially a description of the impact from the traders' side. This research method is qualitative. Type of field research, with a contextual approach to sharia economics. This research uses observation, interviews, and documentation as data collection techniques. The results of this research can be concluded that the increase in fuel prices in 2022 will have a negative impact on basic food traders at Pasar Besar Palangka Raya. The traders' response regarding the 2022 fuel price increase for basic necessities at Pasar Besar Palangka Raya is that basic food traders feel the impact of the fuel price increase and the average number of buyers has decreased after the fuel increase. In terms of elasticity, the demand response includes elastic demand, while the supply response includes inelastic supply. In terms of Islamic economics, the intervention carried out by the government by making a policy to increase fuel prices can be said to be appropriate, but it is still not the price elasticity response that occurs.
Keywords: impact; increase in fuel oil; traders in nine basic commodities
 
Abstrak
Kenaikan harga berbagai komoditas yang tidak dapat dihindari menjadi salah satu dampak kenaikan biaya transportasi yang sudah tentu mengikuti perkembangan kenaikan harga BBM. Penelitian ini bertujuan untuk mengkaji dampak intervensi pemerintah dalam menaikkan harga BBM pada kenaikan harga sembako di pasar tradisional, khususnya deskripsi dampak dari sisi pedagang. Metode penelitian ini adalah kualitatif. Jenis penelitian lapangan (field research), dengan pendekatan kontekstual ekonomi syariah. Penelitian ini menggunakan observasi, wawancara, dan dokumentasi sebagai teknik pengumpulan data. Hasil penelitian ini dapat disimpulkan bahwa kenaikan harga BBM tahun 2022 berdampak negatif terhadap pedagang sembako di Pasar Besar Palangka Raya. Adapun respon pedagang mengenai kenaikan harga BBM tahun 2022 terhadap sembako di Pasar Besar Palangka Raya adalah pedagang sembako merasakan pengaruh dari kenaikan BBM dan jumlah pembeli yang rata-rata menurun setelah kenaikan BBM. Secara elastisitas, respon permintaan termasuk permintaan elastis, sedangkan respon penawaran termasuk penawaran inelastis. Secara ekonomi Islam, intervensi yang dilakukan pemerintah dengan membuat kebijakan menaikkan harga BBM dapat dikatakan sudah sesuai, namun masih belum pada respon elastisitas harga yang terjadi.
Kata kunci: dampak; kenaikan BBM; pedagang sembako
A importância da pesquisa em bem-estar policial: Revisão bibliográfica e propositura de modelo
Authors: Ferreira-Alves Paulo Henrique , Torres Cláudio Vaz , Mattos Márcio Júlio da Silva
Published: July 2024

O presente trabalho teve por objetivo demonstrar a relevância da mensuração do fenômeno de bem-estar de policiais, em especial os militares, com foco na PMDF. Também propõe algumas variáveis antecedentes que possam ajudar em seu incremento nas mais diversas corporações de segurança pública brasileiras, demonstrando suas relevâncias com pesquisas já realizadas no âmbito da segurança pública. Por intermédio de uma metodologia qualitativa, ao logo do texto do artigo foram definidos teórica e empiricamente cada um dos constructos que compõe o modelo, com conceituação, breve histórico e pesquisas recentes relevantes que continham mais de uma variável do modelo e/ou no âmbito da segurança pública. Posteriormente foram apresentadas sugestões de instrumentos psicométricos à disposição na literatura, inclusive com os índices de ajuste encontrados em suas pesquisas seminais e um modelo base para ser utilizado, inteiro, fracionado ou desdobrado, em pesquisas futuras. Com esse delineamento entende-se que o objetivo foi atingido, somado às proposições de perspectivas futuras que possam explorar as limitações do artigo, criando e testando modelos diversos com os constructos propostos para entender melhor fenômenos psicológicos e de gestão que vão gerar benefícios para os policiais, para as corporações e, principalmente, para a sociedade.
THE INFLUENCE OF WORK DISCIPLINE AND SERVICE QUALITY ON CITIZEN SATISFACTION IN MEKAR JAYA VILLAGE, SEPATAN SUB-DISTRICT, TANGERANG DISTRICT
Authors: Ariyanto Ariyanto
Published: July 2024

The purpose of this study was to determine the influence of work discipline and service quality on citizen satisfaction in Mekar Jaya Village, Sepatan District, Tangerang Regency.
The research method used in this research is descriptive with a quantitative approach. The population amounted to 1,652 people, this study used a sampling technique with the accidental sampling method and obtained a sample size in this study of 50 respondents. Data analysis techniques using multiple linear regression.
The results showed that: (1) There is a positive and significant influence of work discipline variables on citizen satisfaction in Mekar Jaya Village, Sepatan District, Tangerang Regency. This is evidenced by the value of tcount> ttable, namely 5.834> 2.012 with a probability value (significance) = 0.000, which is below 0.005. (2) There is a positive and significant influence of service quality variables on citizen satisfaction in Mekar Jaya Village, Sepatan Subdistrict, Tangerang Regency. This is evidenced by the value of tcount> ttable, namely 6.108> 2.012 with a probability value (significance) = 0.000, which is below 0.005. (3) There is a positive and significant influence of work discipline and service quality variables on citizen satisfaction in Mekar Jaya Village, Sepatan Subdistrict, Tangerang Regency. This is evidenced by the value of Fcount> Ftable, namely 38.413> 3.20 with a probability value (significance) = 0.000, which is below 0.005.
Constructive patriotism predicts voting intentions: Evidence from state parliamentary, EU parliamentary, and presidential elections across different EU countries
Authors: Rupar Mirjana , Sekerdej Maciej , Jamróz-Dolińska Katarzyna , Hubená Barbora
Published: July 2024

In the present research, we investigated the link between different forms of national identification (i.e., constructive patriotism, glorification, and conventional patriotism) and intentions to vote in state parliamentary elections in Poland and Spain (Study 1, N = 1,270), presidential elections in Croatia (Study 2, N = 640), and elections for the EU Parliament in Poland, the Czech Republic, and Croatia (Study 3, N = 1,238). In Study 3, we additionally measured European identity. Moreover, we asked about actual voting behavior in Poland (Studies 1 and 3) and Croatia (Studies 2 and 3). The results consistently show that constructive patriotism is linked with greater intentions to vote in all types of elections and across all countries, and with a greater likelihood of voting in state parliamentary elections. In contrast, conventional patriotism had no link with intentions to vote or with actual voting behaviour in any type of election in any of the countries studied. Glorification was linked to lower intentions to vote only in state parliamentary elections. European identity was linked with greater intentions to vote in EU elections. Overall, our results suggest that constructive patriotism is a form of national identification that has particular electoral relevance.
Effectiveness of the Use of Media and Learning Models in Improving Students' Mathematical Communication Skills: Systematic Literature Review
Authors: Prasojo Teguh , Hidayah Isti
Published: July 2024

SLR is researched to describe and find out the level of students' numerical communication capacity. Several parties have utilized a variety of learning materials and learning models to achieve the desired goals. The purpose of this study is to find out which learning tools and models can increase the scientific capacity of students. This question is divided into two tables, namely the media table and the strategy table. Analysts use proper writing audit frameworks to investigate existing diries. From the important articles, it can be concluded that a typical learning model can be utilized in learning materials aimed at supporting the advancement of scientific communication skills.
Empowering Inclusion: AI-Powered Chatbots for Accessible Telecom Services
Authors: Singhb Puneet
Published: July 2024

The integration of artificial intelligence (AI) in the telecommunications sector has introduced groundbreaking advancements, particularly in customer service. AI-powered chatbots have emerged as vital tools for enhancing the accessibility of telecom services, especially for individuals with disabilities. This paper delves into the transformative potential of AI-powered chatbots, examining their role in making telecom services more inclusive and highlighting their social benefits. Through a detailed analysis of current technologies, case studies, and future prospects, we explore how these chat bots can bridge the accessibility gap, ensuring that all customers, regardless of their abilities, can equally benefit from telecom services.
Hubungan Antara Masifnya Fenomena Korupsi Dengan Kesadaran Pajak Warga Negara Indonesia
Authors: I Gusti Ngurah Santika  , Ida Ayu Putu Sri Mas Sunariyanti
Published: July 2024

Pajak merupakan pendapatan negara yang paling utama. Pajak menjadi salah satu iuran wajib masyarakat atas kegiatan perekonomian yang dilakukannya. Upaya pemerintah untuk meningkatkan jumlah pajak dilakukan dengan segala cara supaya wajib pajak membayar pajak tepat waktu dan tanpa merasa dipaksa. Upaya pemerintah ini akan meningkatkan tingkat kepatuhan wajib pajak dalam menjalankan kewajiban perpajakan. Upaya tersebut tentunya berbanding terbalik dengan fenomena akhir-akhir ini, dimana korupsi marak terjadi di Indonesia. Korupsi di Indonesia sudah menjadi permasalahan mendasar bahkan telah mengakar sedemikian dalam sehingga sulit untuk diberantas. Hal ini terlihat semakin lama tindak pidana korupsi di Indonesia semakin meluas. Metode yang digunakan dalam penelitian ini adalah kualitatif deskriptif. Hasil penelitian ini menunjukan, bahwa adanya kasus korupsi pajak menjadi pemicu tidak patuhnya wajib pajak. Faktor berikutnya adalah pandangan negatif wajib pajak atas perilaku korupsi petugas pajak yang dirasa belum sesuai dengan yang diinginkan wajib pajak. Tindakan-tindakan demikian yang dilakukan oleh petugas pajak, menimbulkan kekecewaan wajib pajak terhadap petugas pajak, yang akan mempengaruhi kepatuhan dari wajib pajak. Faktor maraknya kasus korupsi tersebut pada gilirannya melahirkan pandangan negatif wajib pajak terhadap pegawai pajak yang kedepannya dapat menimbulkan ketidakpatuhan terhadap kewajiban membayar dan melaporkan pajak.
SYNTHESIS AND ANALGESIC ACTIVITY OF METHYL-1-ANTIPYRYL-4-AROYL-2,3-DIOXO-2,3,5,10-TETRAHYDROBENZO[B]PYRROLO[2,3-E][1,4]DIAZEPINE-10A(1H) –CARBOXYLATES
Authors: Lyadov Vadim A. , Makrushin Dmitry E. , Denislamova Ekaterina S. , Maslivets Andrey N. , Triandafilova Galina A. , Solodnikov Sergei I.
Published: July 2024

In order to obtain new biologically active compounds, methyl-1-antipyryl-4-aroyl-2,3-dioxo-2,3,5,10-tetrahydrobenzo[b]pyrrolo[2,3-e][1,4]diazepine was synthesized-10a(1H)-carboxylates by reacting 1-antipyryl-4-aroyl-5-methoxycarbonyl-1H-pyrrole-2,3-diones with o-phenylenediamine. The structures of the obtained compounds were confirmed by 1H NMR, IR spectroscopy, X-ray diffraction and elemental analysis. The presence of several electrophilic centers in the structure of antipyryl-substituted 1H-pyrrole-2,3-diones gives them a high reactivity with respect to binucleophilic reagents. Apparently, the described interaction is carried out by the initial nucleophilic attack of one aminogroup of o-phenylenediamine on the C5 carbon atom of the pyrrole-2,3-dione ring, followed by the attack of another aminogroup on the carbonyl carbon atom of the aroyl fragment, closing the diazepine ring. The described reaction is a convenient preparative method for the synthesis of previously undescribed methyl-1-antipyryl-4-aroyl-2,3-dioxo-2,3,5,10-tetrahydrobenzo[b]pyrrolo[2,3-e][1,4]diazepine-10a(1H)-carboxylates, which are of interest as pharmacological substances. The described interaction proceeds quickly and with high yields. The obtained compounds were screened for analgesic activity, as a result of which a more pronounced effect was found in some products compared to the reference drug (diclofenac sodium). A preliminary assessment of acute toxicity was carried out, according to which the derivatives of 2,3,5,10-tetrahydrobenzo[b]pyrrolo[2,3-e][1,4]diazepine proved to be safe for further studies. The survival rate of animals in all groups is 100% after 24 h and 100% after 14 days. Screening of analgesic activity was performed by the hot plate method. Registration of time was carried out from the moment of placement on a hot surface until the appearance of a behavioral response to nociceptive stimulation 60 and 120 min after the administration of substances.
For citation:
Lyadov V.A., Makrushin D.E., Denislamova E.S., Maslivets A.N., Triandafilova G.A., Solodnikov S.I. Synthesis and analgesic activity of methyl-1-antipyryl-4-aroyl-2,3-dioxo-2,3,5,10-tetrahydrobenzo[b]pyrrolo[2,3-e][1,4]diazepine-10a(1H) –carboxylates. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 5. P. 17-23. DOI: 10.6060/ivkkt.20246705.6939.
KINETIC MODELS OF CHAOS IN LINEAR CATALYTIC REACTIONS
Authors: Kol'tsov Nikolay I.
Published: July 2024

Chaos (chaotic oscillations, strange attractors) are aperiodic changes in certain parameters of the dynamic system under study, which differ from other types of oscillations (damped, undamped, multi-periodic) by unusually complex, unpredictable dynamic behavior, and can be observed for an arbitrarily long time. From the theory of dynamical systems it follows that chaotic oscillations can be described by nonlinear systems of ordinary differential equations with three or more independent variables. Until now, such differential equations have been used to construct kinetic models within the framework of the ideal law of mass action, describing chaotic oscillations in homogeneous and heterogeneous catalytic reactions. Moreover, these kinetic models describe chaotic oscillations only for reactions occurring according to stage schemes that are nonlinear with respect to intermediate substances. This article explores the possibility of describing chaotic oscillations by linear systems of ordinary differential equations with three independent variables, which, within the framework of the nonideal Marcelin-de Donde kinetic law, correspond to stage schemes linear in intermediate substances. It is shown that in real conditions, when the Marcelin-de Donde law is satisfied, kinetic models of mechanisms linear in intermediate substances make it possible to describe any complex dynamic behavior of catalytic reactions. Four-stage linear schemes in intermediate substances have been established, the kinetic models of which describe chaotic oscillations of the reactions of interaction between nitrogen monoxides and carbon monoxides (2NO + CO → N2O + CO2) and the oxidation of carbon monoxide (2CO + O2 → 2CO2) on platinum catalysts with Marcelin-de Donde kinetics in an isothermal gradientless reactor.
For citation:
Kol'tsov N.I. Kinetic models of chaos in linear catalytic reactions. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 5. P. 121-127. DOI: 10.6060/ivkkt.20246705.6956.
CARBON NANOSTRUCTURES OBTAINING FROM POLYMER MATERIALS
Authors: Zaritovskii Aleksandr N. , Kotenko Elena N. , Grishchuk Svetlana V.
Published: July 2024

As part of the expansion of raw material base used in the development of technological and productive methods for the synthesis of carbon nanostructures (CNS) and solving the problem of environmentally friendly and economical polymer recycling, the results of investigation of microwave (MW) catalytic pyrolysis of macromolecular compounds from the range of polystyrene, polypropylene, polyethylene terephthalate, polyvinyl alcohol are presented. The information about existing approaches to solving these problems is briefly considered, and the prospects for MW processing of polymers are shown. The process was carried out by microwave treatment of a mixture of polymer raw materials acting as a carbon donor and substances-precursors of metal catalysts – cobalt and nickel compounds, their mixtures, as well as metal iron and nickel. Graphite and carbon fiber were used as temperature regulator. Experiments have demonstrated that effective conversion of the studied compounds occurs only in the presence of MW energy absorbers-converters, regardless of the nature of metal catalyst precursor. According to electron microscopy data, the resulting materials are a mixture of carbon nanostructures of disordered morphology with the predominant content of carbon nanotubes (CNTs) in the reaction products for experiments with polystyrene, polypropylene and polyethylene terephthalate. The use of polypropylene and polyvinyl alcohol leads to the production of carbon nanostructures containing only a small amount of CNTs. X-ray phase analysis data confirm the formation of multi-walled carbon nanotubes as the main structural component of the obtained carbon nanomaterials. It has been suggested that transformation pathways of the investigated hydrocarbons are similar, despite the difference in pyrolysis temperatures, which may be related to the simultaneous processes of polymer cracking, carbonization of decomposition products and CNS synthesis due to the rapid growth of reaction mass temperature during microwave treatment. The efficiency of different precursors of catalytic systems based on transition metals in the processes examined is substantiated. It has been shown that the high carbon content in feedstock promotes the formation of carbon nanostructures, but is not decisive for carbon nanotubes obtaining.
For citation:
Zaritovskii A.N., Kotenko E.N., Grishchuk S.V. Carbon nanostructures obtaining from polymer materials. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 5. P. 99-106. DOI: 10.6060/ivkkt.20246705.6957.
SINTERING PROCESSES, PHASE AND STRUCTURE FORMATION AND PROPERTIES OF ELECTRICAL PORCELAIN WITH THE USE OF MARSHALLIT AND WOLLASTONITE ADDITIVES
Authors: Vereshchagin Vladimir I. , Kurbanbayev Mukhtar Ye. , Yessimov Begen O. , Root Liudmila O. , Mogilevskaya Natalya V.
Published: July 2024

The effect of marshallite upon its complete replacement of quartz and wollastonite additions (2.0 wt.%) on the sintering and phase formation processes, as well as the structure and properties of insulation porcelain was studied. The object of study is insulation porcelain of typical component composition (kaolin, soft clay, feldspar, quartz sand). It has been established that the processes of melting and sintering at firing of the investigated porcelain compositions are not equilibrial. The formation of ternary eutectics fusions of the R2O-Al2O3-SiO2 systems at temperatures of 985 and 1050 °C in amounts of 45–60% does not occur. The formation of a fusion during firing of ceramics occurs due to partial binary eutectics “white feldspar-earth silicon” and “orthoclase feldspar-earth silicon” during the interaction of feldspar with silica-containing components (990–1060 °C). This is due to the fact that primary mullite is formed at temperatures of its stable state above 1200 °C. The actual processes of fusion formation during porcelain firing are not equilibrium. Recrystallization of mullite occurs due to the dissolution of primary mullite in the fusion, followed by crystallization of acicular mullite. Replacing of quartz sand with marshallite leads to a decrease in the temperatures of earth silicon with feldspar interaction and the formation of a primary fusion, which results in a decrease in the ceramics firing temperature by 70° from 1340 to 1270 °C. The addition of wollastonite – CaSiO3 (2 %wt.) intensifies the process of primary mullite dissolution and crystallization of acicular mullite. The length of the mullite needles increases from 2–3 μm up to 7–10 μm, the mullite needles form aggregates, which provides an increase in the bending strength of porcelain by 36% up to 80 MPa.
For citation:
Vereshchagin V.I., Kurbanbayev M.Ye., Yessimov B.O., Root L.O., Mogilevskaya N.V. Sintering processes, phase and structure formation and properties of electrical porcelain with the use of marshallit and wollastonite additives. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 5. P. 87-98. DOI: 10.6060/ivkkt.20246705.6960.
ANALYTICAL TECHNIQUES IN PHARMACEUTICAL POLLUTION OF THE WORLD’S RIVERS; A REVIEW
Authors: Jamur Jasim. M.S.
Published: July 2024

Recent reports of new pollution issues brought on by the presence of medications in the aquatic environment have sparked a great deal of interest in studies aiming at analyzing and mitigating the associated environmental risks, as well as the extent of this contamination. The main sources of pharmaceutical contaminants in natural lakes and rivers include clinic sewage, pharmaceutical production wastewater, and sewage from residences that have been contaminated by drug users' excretions. In evaluating the health of rivers, pharmaceutical pollutants have been identified as one of the emerging pollutants. The previous studies showed that the contaminants in pharmaceuticals that are widely used are non-steroidal anti-inflammatory drugs, antibiotics, antiretrovirals, and anticancer drugs. Additionally, this review demonstrated the use of analytical techniques to examine these contaminants in various kinds of River water. Due to their extremely low concentrations in the aqueous environment (about in the range of ng/L to g/L), it is necessary to apply a technique for highly sensitive and selective multicomponent simultaneous analysis to identify and quantify these products. This analytical technique provides a flexible and reliable means to identify and evaluate pharmaceutical contaminants in river water samples by combining solid phase extraction and hyphenated mass spectrometric techniques. SPE-LC/MS/MS is the main method for estimating the level of pollution.
For citation:
Jamur Jasim. M.S. Analytical techniques in pharmaceutical pollution of the world’s rivers; a review. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 5. P. 6-16. DOI: 10.6060/ivkkt.20246705.7017.
OLEIC ACID AS AN EFFECTIVE SURFACTANT FOR POLY (LACTIC ACID) MICROPARTICLE: A DFT STUDY
Authors: Safa A. Naderi , Sheibani Ali , Baei Mohammad T. , Sayyed-Alangi S. Zahra , Lemeski E. Tazikeh
Published: July 2024

This study aimed to investigate the interaction of oleic acid (OA) with poly (lactic acid) (PLA) microparticle in chloroform and dichloromethane phases using density functional theory (DFT) and time-dependent density functional theory (TDDFT) methods. The study was conducted at the B3LYP-D3/6-31+G** level of theory. The binding energy, dipole moment. and thermodynamic parameters show that the interaction between OA and PLA via C=O….H-O bonds in the most stable state (state I) in the chloroform phase is stronger than in the dichloromethane phase. Negative values of the thermodynamic parameters in the most stable complex and the MEP graphs showed that OA has a positive impact on the adsorption behavior of the PLA. The presence of OA altered the structure of PLA based on theoretical UV-Vis and Infrared (IR) spectra. The findings revealed that using the OA surfactant can improve dispersion and compatibility with the PLA matrix.
For citation:
Safa A.N., Sheibani A., Baei M.T., Sayyed-Alangi S.Z., Lemeski E.T. Oleic acid as an effective surfactant for poly (lactic acid) microparticle: A DFT study. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 6. P. 65-72. DOI: 10.6060/ivkkt.20246706.7069.
 
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REMEDIATION OF OIL-CONTAMINATED SOILS WITH COMPOSITIONS BASED ON HUMIC ACIDS
Authors: Grechishcheva Natalia Yu. , Dmitrieva Elena D. , Starodubtseva Kseniya A.
Published: July 2024

In addition to conventional methods, nowadays new approaches and technologies based on combined application of sorbents and microorganisms are intensively developed for efficient control of oil contaminations. As a biotechnological solution for remediation of various oil-contaminated soils, biocompositions based on an organic matrix – humic acids of peat, and a biological component – a single strain/or an association of oil degrading microorganisms of the genera Rhodococcus and Pseudomonas, have been studied. The efficiency assessment of oil contamination biodegradation using biocompositions was carried out on different types of model oil-contaminated soils with different levels of contamination: grey forest soil, Black Sea pebbles (fraction 20-50mm), constructional broken stone (fraction 10-20mm). Natural soil contaminated with oil products and samples of railroad broken stone (fractions 5-30mm and 35-50mm) were also used. It has been shown that the biocompositions based on three strains of microorganisms – ‘HA R. X5 R. S67 Ps. NF142' – possessed the highest capability of degrading oil hydrocarbons in all systems under study. Biodegradation of oil hydrocarbons upon addition of this biocompositions varied between 62 and 82% depending on the type of oil-contaminated soil, the level of contamination being very high. Monobacterial biocomposition ‘HA Ps.NF142’ has proven to be promising for remediation of oil-contaminated soil ecosystems with a high and very high level of contamination. The increase of the level of biodegradation of oil contamination of soils appears to be due to the combined action of humic acids comprising both the stimulating effect of humic acids on microorganisms – the components of biocompositions and indigenous microflora of model systems, and the detoxifying effect of humic acids in respect of oil hydrocarbons.
For citation:
Grechishcheva N.Yu., Dmitrieva E.D., Starodubtseva K.A. Remediation of oil-contaminated soils with compositions based on humic acids. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 7. P. 136-143. DOI: 10.6060/ivkkt.20246707.6927.
STUDY OF EXTRACTION OF SORBIC AND BENZOIC ACIDS USING BLOCK COPOLYMER “PLURONIC”
Authors: Pakhomova Oksana A. , Polteva Anastasia V. , Mokshina Nadezhda Ya.
Published: July 2024

characterized by the use of harmless, environmentally friendly reagents. The relevance of the work is due to the increasing requirements for extractants capable of ensuring almost complete extraction of sorbic and benzoic acids from food objects for the purpose of their subsequent quantitative determination. The work is devoted to studying the extracting ability of the Pluronic block copolymer in relation to sorbic and benzoic acids and establishing the patterns of interphase distribution in the studied systems. Nonionic surfactant block copolymers of ethylene oxide and propylene oxide provide high quantitative indicators of interfacial distribution of a wide class of organic substances. In small quantities, sorbic and benzoic acid in food products do not have a negative effect on human health, but high levels of preservatives cause pathologies in the body. Therefore, the development of new methods for the extraction and determination of sorbic and benzoic acids in aqueous media with the aim of further monitoring their content in food objects is an urgent task of analytical chemistry. The article presents the calculated distribution coefficients and the degree of extraction of sorbic and benzoic acids using the Pluronic block copolymer and ammonium sulfate as an extractant. The concentrations of analytes and extractant, as well as the ratio of the volumes of aqueous and organic phases at which maximum extraction characteristics are achieved, have been established. Еlectrophoretic analysis of the aqueous phase after extraction is used in the work. Parameters for the quantitative determination of sorbic and benzoic acids were established. Schemes for the interaction of the block copolymer with analytes due to hydrogen bonds are proposed, taking into account the structural features of Pluronic and the extracted substances.
For citation:
Pakhomova O.A., Polteva A.V., Mokshina N.Ya. Study of extraction of sorbic and benzoic acids using block copolymer “Pluronic”. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 7. P. 41-47. DOI: 10.6060/ivkkt.20246707.7020.
ANÁLISE DA VIABILIDADE ECONÔMICA DO SISTEMA LIGHT STEEL FRAMING COMPARADO AO CONCRETO ARMADO NA CONSTRUÇÃO DE UMA UNIDADE BÁSICA DE SAÚDE EM MINAS GERAIS
Authors: Santos Rocha Gustavo
Published: July 2024

Diante da procura por novas técnicas construtivas, do consumo de recursos naturais, da geração de resíduos e na busca do aumento da produtividade e da agilidade no prazo de conclusão das obras, constata-se a premência de novos métodos e novas abordagens que conciliam sustentabilidade com racionalização dos processos. O Light Steel Framing é um sistema construtivo composto por aços galvanizados já demarcados de acordo com o projeto, que unidos a outros elementos, constituem a estrutura da obra, tal método já está consolidado no mercado construtivo internacional e vem tomando espaço no mercado brasileiro. O aço, apesar de aparentar ser um material pesado, é bastante leve se comparado a uma viga de concreto armado, tem elevado desempenho a condições climáticas extremas, flexibilidade, aumento de produtividade, reduz o desperdício de materiais, garantindo redução do impacto ambiental e rapidez no processo de execução da obra, propiciando qualidade, segurança e conforto ao usuário final. Este artigo visa apresentar as etapas construtivas e vantagens do sistema Light Steel Framing, bem como uma análise da sua viabilidade econômica quando comparado ao sistema construtivo convencional. O estudo é baseado em pesquisas bibliográficas e estudo de caso, tendo como referência a construção de uma Unidade Básica de Saúde.
Determination of selection parameters for genetic improvement by evaluating F7 progenies of green chilli
Authors: Negi Paramjeet Singh , Sharma Akhilesh
Published: July 2024

The experimental materials comprised of 27 advance breeding lines derived from eight inter-varietal crosses and six varieties including ‘Surajmukhi’ as standard check. The materials were evaluated in randomized complete block design with three replications during summer 2017. PCV and GCV were high marketable green fruit yield/plant (30.75 and 31.35%, respectively). Similarly, it showed high heritability along with high genetic advance. However, in general, high heritability along with moderate PCV, GCV and geneticadvance were observed for majority of the traits. Green fruit yield/plant showed positive and significant correlations with fruit length, fruit girth, fruit width, leaf width, plant height, average green fruit weight, number of marketable green fruits/ plant and capsaicin content at both genotypic and phenotypic levels. Marketable green fruits/plant had the maximum positive direct effect on marketable green fruit yield per plant followed by average green fruit weight while leaf length, plant height and secondary branches/plant alsocontributed directly to a limited extent at both phenotypic and genotypic levels. Further, marketable green fruits/plant followed by average green fruit weight had the maximum indirect contribution to the total positive association. Thus, selection for these traits should be taken as a criterion for yield improvement in chilli.
Effect of farming conditions on bacterial wilt incidence in brinjal
Authors: Rathore Neha , Katoch Viveka , Kumari Vedna , Chadha Sanjay , Akanksha Bharti , Kumar Sandeep , Sharma Shweta
Published: July 2024

Brinjal is one of the important vegetable crops on account of its medicinal value. Crop is vulnerable to plethora of diseases of which bacterial wilt is most devastating disease in the tropical, subtropical and temperate regions of the world, causing heavy economic loss. The chemical control of the disease is very expensive and the only way to sustain cultivation is by growing bacterial wilt resistant varieties. Of late, cultivated resistant varieties are gradually succumbing to the disease. Thus, the experiment was conducted to evaluate new bacterial wilt resistant lines (27) under mid hill conditions of Himachal Pradesh. The experiment was laid down under conventional farming and zero budget natural farming conditions. Observation was recorded on plant survival and the lines were categorized according to Sitaramiah scale (1981). The results indicated that BRBWRES-1, BRBWRES-2, SM 6-7, Hisar Shyamal, Arka Keshav, Arka Nidhi, Haritha, Muktakeshi and Kashi Prakash manifested no bacterial wilt incidence and were categorized as immune. Thus, these lines can be recommended for cultivation in bacterial wilt prone areas.
Effect of -irradiation on in vitro pollen germination of muskmelon (Cucumis melo L.)
Authors: Kaur HarAmrit , Sharma Sat Pal , Kalia Anu , Sarao NK
Published: July 2024

Induction of haploid plants in vegetable crops through ãirradiated pollen method is of utmost importance in contemporary vegetable breeding to accelerate the breeding cycle. But the major problem of this technique is the sensitivity of pollen grains to higher irradiation doses. Present work investigated the effect of different -irradiation dosage (250 to 400 Gy) on percent germination and tube length of pollen grains of muskmelon (Cucumis melo L.) genotype, MS-5 on Brewbakers medium. The observations were recorded after 1, 2 and 3 hours of incubation. Irradiated pollen didn’t show any sign of germination at 1 and 2 hours, however germination initiation was observed in the nonirradiated pollen. A decrease in percent germination and pollen tube growth was observed with incremental irradiation dose. Very little germination or abnormal pollen tube growth was recorded for pollen grains irradiated at 400 Gy. This study advocates the need for deriving out the appropriate ã-irradiation dose specific for the muskmelongenotype besides obtaining the extent of the lethality for the irradiated pollen grains for its possible application in generation of haploids through parthenogenesis.