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Full-Text Articles in Engineering

Using Chatgpt With Novice Arduino Programmers: Effects On Performance, Interest, Self-Efficacy, And Programming Ability, Donald M. Johnson, Will Doss, Christopher M. Estepp May 2024

Using Chatgpt With Novice Arduino Programmers: Effects On Performance, Interest, Self-Efficacy, And Programming Ability, Donald M. Johnson, Will Doss, Christopher M. Estepp

Journal of Research in Technical Careers

A posttest-only control group experimental design compared novice Arduino programmers who developed their own programs (self-programming group, n =17) with novice Arduino programmers who used ChatGPT 3.5 to write their programs (ChatGPT-programming group, n = 16) on the dependent variables of programming scores, interest in Arduino programming, Arduino programming self-efficacy, Arduino programming posttest scores, and types of programming errors. Students were undergraduates in an introductory agricultural systems technology course in Fall 2023. The results indicated no significant (p < .10) differences between groups for programming rubric scores (p = .50) or interest in Arduino programming (p = .50). There were significant differences for Arduino programming self-efficacy, (p = .03, Cohen’s d = 0.75) and Arduino posttest scores, (p = .03, Cohen’s d = 0.76); students in the self-programming group scored significantly higher on both measures. Analysis of students’ errors indicated the ChatGPT group made significantly (p < .01) more program punctuation errors. These results indicated novice students writing their own programs developed greater Arduino programming self-efficacy and programming ability than novice students using ChatGPT. Nevertheless, ChatGPT may still play an important role in assisting novices to write microcontroller programs.


Commercial Enablers Of China’S Cyber-Intelligence And Information Operations, Ethan Mansour, Victor Mukora May 2024

Commercial Enablers Of China’S Cyber-Intelligence And Information Operations, Ethan Mansour, Victor Mukora

Military Cyber Affairs

In a globally commercialized information environment, China uses evolving commercial enabler networks to position and project its goals. They do this through cyber, intelligence, and information operations. This paper breaks down the types of commercial enablers and how they are used operationally. It will also address the CCP's strategy to gather and influence foreign and domestic populations throughout cyberspace. Finally, we conclude with recommendations for mitigating the influence of PRC commercial enablers.


Presence Of Atheromatous Plaques And Theirs Effects On The Blood Flow, Belhocine Mostefa Bm, Amrani Hichem Ah, Fedaoui Kamel Dr, Mazouz Hammoudi Mh May 2024

Presence Of Atheromatous Plaques And Theirs Effects On The Blood Flow, Belhocine Mostefa Bm, Amrani Hichem Ah, Fedaoui Kamel Dr, Mazouz Hammoudi Mh

Emirates Journal for Engineering Research

The paper utilizes a finite element method to study both the blood flow and atheromatous plaques. Specifically, the COMSOL finite element package is employed to achieve a fluid model. COMSOL is a powerful finite element tool commonly used in various research and industrial domains to study multiphysics problems. The focus of the investigation is on the geometric aspects of the atheromatous plaques. The study considers different forms and arrangements of stenosis, taking into account the irregularities formed by various shapes of the plaques and the resulting flow patterns. The key findings of the research suggest that the pressure and velocity …


Synthesis Of Acetylene Diols With The Participation Of The Bu4noh/Dmso/H2o Catalytic Systems, Muyassar K. Salieva, Odiljon E. Ziyadullayev, Guzal K. Otamukhamedova, Rifkat F. Talipov, Lochin K. Ablakulov May 2024

Synthesis Of Acetylene Diols With The Participation Of The Bu4noh/Dmso/H2o Catalytic Systems, Muyassar K. Salieva, Odiljon E. Ziyadullayev, Guzal K. Otamukhamedova, Rifkat F. Talipov, Lochin K. Ablakulov

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this work in this study, acetylene alcohols containing heteroatomic substituents in their molecular composition- 2-(-thiophen-2-yl)but-3-yn-2-ol, 2-(3-methylthiophen-2-yl)but-3-yn-2-ol, 2-(furan-2-yl)but-3yn-2-ol, 2-(pyridin-4-yl)but-3-yn-2-ol, 2-(5-chlorothiophen-2-yl)but-3-yn-2-ol, 2-(5-bromothiophen-2yl)but-3-yn-2-ol acetylene diols were synthesized based on the reaction with acetone in a dimethyl sulfoxide solvent in the presence of the Bu4NOH/DMSO/H2O catalytic system. The influence of the molar ratio of starting materials, reaction duration, temperature, nature of the catalyst and solvents on the product yield was systematically studied. The composition, purity and structure of the new generation of synthesized acetylenediols have been confirmed by modern physicochemical methods. The mechanism of the reaction process …


Synthesis Of High Molecular Mass Resins Based On Furfuryl Alcohol, Boysayid U. Sayidov, Latif E. Jumanov, Muzaffar G. Alimukhamedov, Sherali A. Umarov, Farhod A. Magrupov May 2024

Synthesis Of High Molecular Mass Resins Based On Furfuryl Alcohol, Boysayid U. Sayidov, Latif E. Jumanov, Muzaffar G. Alimukhamedov, Sherali A. Umarov, Farhod A. Magrupov

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of the work is to study the process of synthesis of furfuryl oligomers with high molecular weight at various ratios of furfuryl alcohol and hydroxyl-containing polyether polyol. The influence of the process method on the yield of high-molecular furfuryl oligomer is shown - with a one-step synthesis method with an increase in the amount of furfuryl alcohol from 20 to 50 moles per 1 mole of polyether polyol, the yield of the final product decreases from 75% to 56%, apparently due to high exothermic effects, causing gelation systems. In contrast to the one-time introduction of the catalyst, its …


Synthesis And Technology Of Vinyl Esters Of Aromatic Carboxylic Acids Based On Vinyl Acetate, Askar B. Parmanov, Suvonkul E. Nurmanov, Saida S. Abdurakhmanova, Sarvinoz I. Tirkasheva, Begzod F. Adashev May 2024

Synthesis And Technology Of Vinyl Esters Of Aromatic Carboxylic Acids Based On Vinyl Acetate, Askar B. Parmanov, Suvonkul E. Nurmanov, Saida S. Abdurakhmanova, Sarvinoz I. Tirkasheva, Begzod F. Adashev

CHEMISTRY AND CHEMICAL ENGINEERING

In this work the vinylation reactions of aromatic carboxylic acids with vinyl acetate, which contain various substituents, in the presence of 2-chloro-4,6-dimethoxy-1,3,5-triazine were studied for the first time. The influence of the nature of the starting materials, temperature, reaction duration, solvent and reagents - zinc triflate (Zn(OTf)2, 3,3-diphenylbinaphthol (3,3'-Ph2BINOL-2Li), tertiary potassium butylate (KOtrBu), butyllithium (BuLi) for the synthesis of vinyl esters. The synthesis of vinyl esters of aromatic carboxylic acids was carried out: benzoiс, 2-phenylacetic, 4-methylbenzoic, 4-methoxybenzoic, 3,4-dimethoxybenzoic, 2-brombenzoic, 4-brombenzoic, 4-fluorobenzoic, 3-nitrobenzoic, 4-nitrobenzoic, 4-tertiary butylbenzoic, 2-chlorobenzoic, 4-chlorobenzoic, 3-hydroxybenzoic and 4-hydroxybenzoic acids has been studied. …


Synthesis Of Internal Acetylene Alcohols Based On The Sonogashira Reaction Of Terminal Acetylene Alcohols And Benzolchloride, Guzal K. Otamukhamedova, Odiljon E. Ziyadullayev, Abduvahob Ikramov, Sarvinoz I. Tirkasheva May 2024

Synthesis Of Internal Acetylene Alcohols Based On The Sonogashira Reaction Of Terminal Acetylene Alcohols And Benzolchloride, Guzal K. Otamukhamedova, Odiljon E. Ziyadullayev, Abduvahob Ikramov, Sarvinoz I. Tirkasheva

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of the study is to develop a new catalytic system for the synthesis of internal acetylene alcohols from the Sonogastric coupling reaction of terminal acetylene alcohols and benzolchloride. For the first time in this work, internal acetylene alcohols have been synthesized based on reactions of some terminal acetylene alcohols – 3,4-dimethylpentin-1-ol-3, 3,4,4-trimethylpentin-1-ol-3, 1-ethynylcyclohexanol-1, 2-ethynyladamantanol-2, 2-phenylbutin-3-ol-2, 2-(naphthyl-2)butyn-3-ol-2, 2-(furanyl-2)butyn-3-ol-2 and 2-(pyridinyl-4)butyn-3-ol-2 with chloridebenzene. In order to achieve high product productivity in the Sonogashira reaction, alternative conditions have been identified by studying the molar ratios, spatial structure, induction effects of substituents, solvent and catalyst nature, as well as temperature, reaction duration …


Study Of The Influence Of B2o3 Oxide On The Physical And Technical Properties Of Ground Enamel Obtained Based On Local Raw Material Components, Shoxrux B. Naimov, Mastura Kh. Aripova May 2024

Study Of The Influence Of B2o3 Oxide On The Physical And Technical Properties Of Ground Enamel Obtained Based On Local Raw Material Components, Shoxrux B. Naimov, Mastura Kh. Aripova

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of the study was to obtain ground enamel based on local raw materials and to study the effect of boron oxide. The selection of local raw materials for producing ground enamel showed that the resulting glass compositions are in the SiO2–Al2O3–Na2O–K2O–CaO–B2O3 system. To adjust the properties, additives of nickel oxide and cobalt oxide were used. The properties of the developed compositions of primer enamels meet the requirements of GOST 24405-80. It has been determined that the addition of boron and an increase in its amount …


Formation Of Luminescent Coatings With The Use Of Low Melting Glass, Eygeniy N. Poddenezhny, Ekaterina E. Trusova, Andrei A. Boiko, Ekaterina R. Kravcova, Olga V. Davydova May 2024

Formation Of Luminescent Coatings With The Use Of Low Melting Glass, Eygeniy N. Poddenezhny, Ekaterina E. Trusova, Andrei A. Boiko, Ekaterina R. Kravcova, Olga V. Davydova

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the present research is to develop compounds and technologies for applying the luminous vitrocrystalline compounds to smooth and ribbed glass substrates in LED lamp structure with a remote photoconverter that contains oxide low melting glass as the base and nanostructured cerium–doped yttrium–aluminum garnet powder as the luminophore. The luminescent coatings based on nanostructured cerium doped yttrium-aluminum garnet powder and low melting glass of composition BaO-Bi2O3-B2O3-K2O-SiO2 where prepared. YAG:Ce3+ powder was synthesized by the method of thermochemical reaction. Silica glass powder was introduced into the composition …


Anomalous Of Resistance And Magnetic Susceptibility At 280-310 K And Ambient Pressure In Bismuth Cuprates Synthesized By Solar Energy, Dilbara Dj. Gulamova, Elyor B. Eshonkulov, Valeriya R. Li, Grigor I. Mamniashvili, Timur I. Gulamov May 2024

Anomalous Of Resistance And Magnetic Susceptibility At 280-310 K And Ambient Pressure In Bismuth Cuprates Synthesized By Solar Energy, Dilbara Dj. Gulamova, Elyor B. Eshonkulov, Valeriya R. Li, Grigor I. Mamniashvili, Timur I. Gulamov

CHEMISTRY AND CHEMICAL ENGINEERING

In order to obtain the full content of high-temperature superconducting phases using the “Super Fast Alloys Quenching” technology in the Large Solar Furnace (Parkent), precursors of bismuth cuprates of the series Bi1,7Pb0,3Sr2Ca(n-1)CunOy, n=3-30 were synthesized. Methods for study the properties of precursors are presented. The oriented nano-sized microstructure and layered structure of nanocrystalline nuclei are shown. The phase composition of the precursors at the beginning of the series (n=3-5) is represented by X-ray amorphous and crystalline phases. An increase in the content of CaO and CuO destabilizes the …


Waste Utilization In Korean Cement Plants, Geun-Seong Lee, Zebo Abdullaevna Babakhanova, Mastura Khikmatovna Aripova May 2024

Waste Utilization In Korean Cement Plants, Geun-Seong Lee, Zebo Abdullaevna Babakhanova, Mastura Khikmatovna Aripova

CHEMISTRY AND CHEMICAL ENGINEERING

The kiln process in cement plant has the advantage of completely and effectively destroying and burning all organic substances due to high temperature and long residence time, oxygen atmosphere and excellent mixing effect, alkaline conditions of raw materials, and incorporation of trace metals into clinker, and plays a role as a pollutant emission barrier during waste utilization. Waste utilization technology is now proven and successful in cement plants. The waste utilization in Korean cement plants are greatly expanding in the view of energy and material recoveries, and economics as well as environmental preservation. Research on waste utilization in the Korean …


Building Services Engineering May/June 2024 May 2024

Building Services Engineering May/June 2024

Building Services Engineering

No abstract provided.


Multilayer Shielding Design And Analysis Of Optimal Thickness For The Storage Of Highly Radioactive Sources Concerning Environmental Safety, Md. Mahfuzul Haque Rafi, Asma Ul Husna, Abdus Sattar Mollah May 2024

Multilayer Shielding Design And Analysis Of Optimal Thickness For The Storage Of Highly Radioactive Sources Concerning Environmental Safety, Md. Mahfuzul Haque Rafi, Asma Ul Husna, Abdus Sattar Mollah

International Journal of Nuclear Security

As a kind of radiological protection, multilayer shielding is superior to a single-layer shield in terms of blocking off radiation. This study examined a multilayer shielding strategy to protect employees from potentially harmful gamma radiation from highly radioactive sources such as 60Co. This paper presents a novel strategy for cost-effective and environmentally safe radiation protection by aligning expensive and heavy materials such as W and Pb to improve their effectiveness and limit exposure below the occupational dose. The largely unpublished set of final exposure rates for the W–Pb–Fe combination was calculated by the numerical interpolation method in MATLAB software. …


A Review And Analysis Of Nuclear Hydrogen Production In Generation Iv Reactors, Arijit Saha Ayon, Ashiqur Rahman Alif, A. S. M. Nasim May 2024

A Review And Analysis Of Nuclear Hydrogen Production In Generation Iv Reactors, Arijit Saha Ayon, Ashiqur Rahman Alif, A. S. M. Nasim

International Journal of Nuclear Security

Hydrogen is becoming increasingly vital as a chemical element in the progress of human civilization. Hydrogen finds application in the creation of ammonia, the manufacturing of nitrogen-based fertilizers, and a wide range of organic compounds, including methanol and propulsion fuel for space exploration missions. Additionally, there are ongoing experiments in the automotive industry to harness hydrogen-based fuel cells as an alternative power source. In modern technology, multiple methods and strategies for hydrogen production originate from diverse sources, such as fossil fuels, renewable energy, nuclear energy, and more. Generation IV nuclear reactors significantly affect the production of hydrogen. These reactors operate …


Modeling And Analysis Of Neutron Flux Of A Vver 1200 Reactor Core Using Monte Carlo Code Openmc, K. M. Rakib Al Hasan, Dr. Debashis Datta, Altab Hossain May 2024

Modeling And Analysis Of Neutron Flux Of A Vver 1200 Reactor Core Using Monte Carlo Code Openmc, K. M. Rakib Al Hasan, Dr. Debashis Datta, Altab Hossain

International Journal of Nuclear Security

Nuclear reactors and their associated facilities are complex systems that require accurate modeling and analysis to ensure safety, security, and efficient operation. This study aims to model and analyze the neutron flux of a generic VVER 1200 reactor core using the Monte Carlo code OpenMC. For the purpose of this analysis, a generic model of the VVER 1200 reactor core was developed using an OpenMC simulation environment. Furthermore, using this model, the neutron flux spectrum inside the reactor core was evaluated, from which neutron fluence was calculated accordingly. This study analyzed the effect of neutron flux on the developed model …


Safety And Security Analysis Of Vver-1200 Reactor Pressure Vessel Under Pressurized Thermal Shock, Mohammed Sarim Salman Karim, Dr. Debashis Datta, Altab Hossain May 2024

Safety And Security Analysis Of Vver-1200 Reactor Pressure Vessel Under Pressurized Thermal Shock, Mohammed Sarim Salman Karim, Dr. Debashis Datta, Altab Hossain

International Journal of Nuclear Security

The reactor pressure vessel (RPV) is an important component of a nuclear power plant and of great concern to safety and security globally. Thus, the thermal system of an RPV should be ensured properly through an evaluation system that closely monitors and considers its integrity. This article describes the thermomechanical analyses for a pressurized thermal shock (PTS) scenario of a VVER-1200 RPV owing to a loss of coolant accident (LOCA) and activation of the emergency core cooling system (ECCS). The LOCA transient and activation of ECCS are modeled using ANSYS simulation software. From the analyses of the emergency core cooling …


Safety Analysis In Ap-1000 Nuclear Power Plant Against Primary Loop Coolant Pump And Fuel Failures, Fabiano Gibson Daud Thulu, Hailemichael Guadie Mengsitu, Chifundo Tenthani, Paul Stone Macheso May 2024

Safety Analysis In Ap-1000 Nuclear Power Plant Against Primary Loop Coolant Pump And Fuel Failures, Fabiano Gibson Daud Thulu, Hailemichael Guadie Mengsitu, Chifundo Tenthani, Paul Stone Macheso

International Journal of Nuclear Security

This study focused on the best-estimated thermal-hydraulic calculations performed regarding the AP-1000 nuclear power plant (NPP) under primary coolant loop pump and fuel failures. Primary coolant pump and fuel failure transients are important design-basis accidents in NPP safety assessments. This work examined the primary reactor’s safety margins of fuel and cladding peak temperature, primary and secondary loop pressure, hydrogen formation, and primary and secondary flow rates. The Adaptive System Thermal-Hydraulics program was used in the simulation and event progression analysis. The results showed that the peak fuel surface temperature was kept below the licensing design limit. No observation of corium …


Threat Modeling Based On A Design Basis Threat For Nuclear Security, Abu Zafor Mohammad Salahuddin, Altab Hossain, Mohammad Shawkat Akbar May 2024

Threat Modeling Based On A Design Basis Threat For Nuclear Security, Abu Zafor Mohammad Salahuddin, Altab Hossain, Mohammad Shawkat Akbar

International Journal of Nuclear Security

Identification of the design basis threat (DBT) of a nuclear facility is an important factor of overall safety, for which the operator is mainly responsible per the guidelines of the International Atomic Energy Agency. As threat levels increase especially threats beyond the DBT-the responsibility of the state also increases. In recent years, only a few studies on nuclear security and DBTs have comprehensively detailed the full spectrum of nuclear facilities in a nation. Thus, this paper presents the correlation between an actual threat and the DBT. The objectives of the study are to assist in establishing physical protection system (PPS) …


Design And Development Of A Radiation Survey And Rescue Robot With Shielding Of Electronic Equipment From Radiation Damage With Image Radiation Mapping Facility, Md. Sifatul Muktadir, Md. Nazmul Hassan, Md. Saimon Siddique, Dewan Nazmun Nur, Altab Hossain, Ahnaf Tahmid Chowdhury May 2024

Design And Development Of A Radiation Survey And Rescue Robot With Shielding Of Electronic Equipment From Radiation Damage With Image Radiation Mapping Facility, Md. Sifatul Muktadir, Md. Nazmul Hassan, Md. Saimon Siddique, Dewan Nazmun Nur, Altab Hossain, Ahnaf Tahmid Chowdhury

International Journal of Nuclear Security

The use of remote-controlled robots in emergency fields is a necessary requirement at present, which includes the nuclear engineering field because the radioactive environment creates adverse effects on human health. This work describes the development of a remotely controlled rover capable of detecting ionizing radiation, isolating radiation sources using a robotic arm, and sufficient shielding for its internal components. A custom-made Geiger–Muller counter has been used to detect ionizing radiation. The radioactive environment is not only harmful for humans but also can cause severe damage to the electronic circuit mounted on the robot. Therefore, a custom concrete material sandwiched between …


Renewable Energy Misinformation: A Literature Based Approach To Rebutting False Claims, Matthew Ard Apr 2024

Renewable Energy Misinformation: A Literature Based Approach To Rebutting False Claims, Matthew Ard

McNair Research Journal SJSU

No abstract provided.


Experimental Analysis Study Wave Drift Force Of Moored Floating Production Units (Fpu), Arifin Rifliansah, Wibowo Harso Nugroho Apr 2024

Experimental Analysis Study Wave Drift Force Of Moored Floating Production Units (Fpu), Arifin Rifliansah, Wibowo Harso Nugroho

Makara Journal of Technology

Drift forces caused by sea waves and currents are an important aspect that needs to be studied in planning moored floating structures, especially Floating Production Units (FPU) type ships which are operated for oil and gas exploration. This study describes the drift forces on the FPU which is subjected to environmental loads in the form of waves. The slow-drift movement that occurs in a moored FPU, and experiencing irregular waves is a very important problem. The complexity of determining drift forces analytically and numerically requires the use of hydrodynamics model test. In the model test on a certain model scale …


Experimental And Numerical Studies On The Compressive Strength Test Of Recycled Aggregate Concrete Using Digital Image Correlation, Bastian Okto Bangkit Sentosa, Joshua Ferdinand, Nuraziz Handika Apr 2024

Experimental And Numerical Studies On The Compressive Strength Test Of Recycled Aggregate Concrete Using Digital Image Correlation, Bastian Okto Bangkit Sentosa, Joshua Ferdinand, Nuraziz Handika

Makara Journal of Technology

The utilization of recycled aggregate (RA) as substitute of natural aggregate in concrete contributes to the research of sustainable building construction materials. Many applications of RA have been studied worldwide. However, the application of RA with a specific range of strength and specific damage behavior requires further study. This research aims to examine the mechanical characteristics of RA concrete, particularly its load–displacement response and crack pattern, through the experimental and numerical studies of compressive strength test. Laboratory concrete waste from cylindrical sample with 30–35 MPa strength was chosen as RA. The digital image correlation (DIC) method was applied throughout the …


Hybrid Method Neighbor Node Discovery In Wireless Sensor Networks: A Framework, Sagar Mekala, Shahu Chatrapati Kaila, Jyothi Rani Matang Apr 2024

Hybrid Method Neighbor Node Discovery In Wireless Sensor Networks: A Framework, Sagar Mekala, Shahu Chatrapati Kaila, Jyothi Rani Matang

Makara Journal of Technology

Wireless devices are now being adapted for diverse purposes, such as healthcare, agriculture, transportation, and tactical operations, which present challenges in network formation owing to high device mobility. Current methods rely on discovery techniques for forming wireless sensor networks (WSNs); however, the existing research has been criticized for its high time complexity and redundant neighbor discovery process. In this study, we provide a hybrid strategy to effectively handle the difficulties of locating neighboring nodes in WSNs. Our method combines several strategies to produce precise and effective neighbor detection. Herein, shared memory–based discovery, a beacon technique, and range and distance overlap …


Study Of Kinetics Of Hydrocarbon Gas Purification With Composite Absorbents, Oybek Aripdjanov, Shavkat Nurullaev, Shodiyakhon Azimova Apr 2024

Study Of Kinetics Of Hydrocarbon Gas Purification With Composite Absorbents, Oybek Aripdjanov, Shavkat Nurullaev, Shodiyakhon Azimova

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the work is to improve the process of natural gas purification from acidic components using a composite absorbent. To study the sorption of acidic components in the gas composition, a chromatographic analysis method was used. The kinetics and rate of corrosion of carbon steel grade st.10 when using composite absorbents MDEA +DEA + AVRP have been studied. The results of the study show that the volume of absorption increased from 0.55 mol/mol to 0.65 mol/mol, and the amount of H2S in the purified gas decreased from 0.022 g/m3 to 0.014 g/m3. Corrosion …


Study Of Reactive Distillation Equipment For Eterification Process, Abbos Elmanov, Abdulaziz Bakhtiyorov, Adham Norkobilov, Olimjon Maksudov, Zarif Oripov Apr 2024

Study Of Reactive Distillation Equipment For Eterification Process, Abbos Elmanov, Abdulaziz Bakhtiyorov, Adham Norkobilov, Olimjon Maksudov, Zarif Oripov

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this work is to study the chemical technological processes for eterification processes, and the reactive distillation unit, which carries out the reaction and separation process in one device, was chosen as the object of research. А reаctive distillаtion system is exаmined to produce for the production of Ethyl Acetate (EtAc) viа eterificаtion of acetic acid (HAc) with ethаnol. Optimizаtion methods using sensitivity analysis аre аlso conducted. Cаlculаtion of vаpor liquid equilibrium of the mixture system is done using UNIFАC model. Heat integration from the distillate stream of the column to the acid feed stream and from bottom …


Modeling And Performance Analysis Of Solid Oxide Fuel Cell, Mariya Pecherskaya, Khakimjan Butanov, Suhrob A. Ibodullaev, Olim Ruzimuradov, Shavkat Mamatkulov Apr 2024

Modeling And Performance Analysis Of Solid Oxide Fuel Cell, Mariya Pecherskaya, Khakimjan Butanov, Suhrob A. Ibodullaev, Olim Ruzimuradov, Shavkat Mamatkulov

CHEMISTRY AND CHEMICAL ENGINEERING

A three-dimensional numerical model of the system configurations of various types of solid oxide fuel cells (SOFCs) is used and the effect of parameters on SOFC performance is numerically investigated using COMSOL Multiphysics. The effect of parameters such as support layer thickness, operating temperature, and electrode porosity are shown in the polarization and power curves for each model. The results of the study showed the advantages of the anode-supported SOFC compared to cathode- and electrolyte-supported SOFC.

Theoretical calculations demonstrate the highest output power density in the anode-supported SOFC at 900 ℃, and reach a value of 0.585 W cm-2 …


Alkynylation Of Benzaldehyde And Its R-Substituted Derivatives Based On Lithium Phenylacetylenide, Sanat B. Samatov, Odiljon E. Ziyadullayev, Abduvakhab Ikramov Apr 2024

Alkynylation Of Benzaldehyde And Its R-Substituted Derivatives Based On Lithium Phenylacetylenide, Sanat B. Samatov, Odiljon E. Ziyadullayev, Abduvakhab Ikramov

CHEMISTRY AND CHEMICAL ENGINEERING

The purpose of this research work is for the first time the synthesis of the corresponding acetylene alcohols based on the alkynylation reaction of isolated benzaldehyde and its R-substituted derivatives in the BuLi/TGF system. The study proposed the reaction stages for the synthesis of acetylene alcohols in the selected BuLi/TGF system, the influence of factors influencing the process, including temperature, reaction duration and nature selected solvents. The structure of the synthesized acetylene alcohols was confirmed by modern methods of physicochemical analysis (1H NMR, 13C NMR). In addition, the effect of substituents in benzaldehyde and its R-substituted derivatives …


Numerical Calculation Of The Flame Spreading Over A Methane Hydrate Surface, Otabek Nigmatov, Oksana Ismailova Apr 2024

Numerical Calculation Of The Flame Spreading Over A Methane Hydrate Surface, Otabek Nigmatov, Oksana Ismailova

CHEMISTRY AND CHEMICAL ENGINEERING

The Methane Hydrate is expected as an energy source and is being as a medium distance transport means of natural gas alternative of LNG (Liquefied Natural Gas). During the natural gas transportation, fire accidents are concerned. In the present study, the flame spreading over a methane hydrate surface has been studied numerically as a function of hydrate surface temperature, Ts. When Ts = 173 K (-100℃), lower than the dissociation temperature (Td = 183 K (-90℃)), the flame spreading speed is around 6.5 mm/s, while the flame spreading speed at Ts = 193 K (-80℃), …


Dft Study Of Quantum Chemical Parameters Of 4-Amino-2-Mercaptobenzimidazole And Their Tautomeric Forms, Dilnoza Rahmonova, Alisher Eshimbetov, Lobar Gapurova, Zuhra Ch. Kadirova, Shakhnoza Kadirova Apr 2024

Dft Study Of Quantum Chemical Parameters Of 4-Amino-2-Mercaptobenzimidazole And Their Tautomeric Forms, Dilnoza Rahmonova, Alisher Eshimbetov, Lobar Gapurova, Zuhra Ch. Kadirova, Shakhnoza Kadirova

CHEMISTRY AND CHEMICAL ENGINEERING

Coordination competing donor centers, electronic and geometric structures of the 4-amino-2-mercaptobenzimidazole ligand molecule were studied using quantum chemical calculation by the DFT / 6-31G method (d, p). It was shown that during the formation of the metal complex, the ligand is coordinated through the localized nitrogen atom of the imidazole ring. In this study, the total energies (Etot) of 4-amino-2-mercaptobenzimidazole (1) and its tautomeric forms (2 and 3) were calculated. And also, the energies of boundary molecular orbitals, the energy gap between boundary MOs (ΔE) and the distribution of the total charge on atoms and boundary orbitals were determined. In …


The Effect Of Hydrogen Peroxide And Potassium Amylxanthate On The Surface Properties Of Chalcocite And Enargite, Berdakh T. Daniyarov, Hajime Miki, Daminbek A. Ziyatov, Shahlo Daminova Apr 2024

The Effect Of Hydrogen Peroxide And Potassium Amylxanthate On The Surface Properties Of Chalcocite And Enargite, Berdakh T. Daniyarov, Hajime Miki, Daminbek A. Ziyatov, Shahlo Daminova

CHEMISTRY AND CHEMICAL ENGINEERING

The effect on the surface properties and floatability of chalcocite and enargite after oxidative treatment with hydrogen peroxide (H2O2) in the presence and absence of potassium amylxanthate (PAX) as a collector was studied. In this research, flotation tests were carried out on mixed and individual minerals. Oxidative treatment with hydrogen peroxide had a negative effect on the floatability of chalcocite and enargite. PAX adsorption analysis shows that enargite adsorbs PAX faster than chalcocite. Moreover, Fourier transform infrared spectroscopy analysis shows that PAX was adsorbed in the form of copper amylxanthate on chalcocite and enargite surfaces. In …