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Full-Text Articles in Engineering

Towards Future Sustainable Infrastructure: The Role Of Technical Audit In Tanzania’S Public Works, George C. Haule Jun 2025

Towards Future Sustainable Infrastructure: The Role Of Technical Audit In Tanzania’S Public Works, George C. Haule

Tanzania Journal of Engineering and Technology (TJET)

This study aimed to investigate the vital role and impact of technical audits in promoting sustainable infrastructure development in Tanzania. The role and effects of technical audits in long-term infrastructure development were studied using a mixed-methods approach with both quantitative and qualitative parts. Data were collected through analysis of technical audit documentation, a semi-structured questionnaire, and stakeholder interviews. The study revealed the various dimensions of infrastructure investment projects, including initiation and planning, design, procurement of contractors and consultants, contract management, environment, health, and safety. The technical audit findings reported weaknesses or non-performance issues in infrastructure planning at the national level …


Wet Gas Metering Performance Using Conventional Flow Measurement Devices, Vitali Mwinyi Jun 2025

Wet Gas Metering Performance Using Conventional Flow Measurement Devices, Vitali Mwinyi

Tanzania Journal of Engineering and Technology (TJET)

The demand for and production of natural wet gas from wells has significantly risen in recent years. Although natural gas liquids hold substantial value in the oil and gas market, their presence in wet gas adversely affects gas metering, leading to overreading during measurement. A comprehensive study has been undertaken to formulate and enhance correlations for rectifying overreading in wet gas metering. Nevertheless, most current correlations are designed for horizontal configurations of traditional meters. Mitigating this constraint is crucial to consider the impact of gravity on pressure loss in vertically oriented systems. This study seeks to evaluate the efficacy of …


Energy Optimal Coverage Motion Trajectory Generation Using A Fourth-Order Motion Profile, Mathias Halinga Jun 2025

Energy Optimal Coverage Motion Trajectory Generation Using A Fourth-Order Motion Profile, Mathias Halinga

Tanzania Journal of Engineering and Technology (TJET)

Industrial machines are widely used in manufacturing sector to manufacture several products to meet customer demands. Most of these industries runs all the time throughout a day leading to high operating cost. To cut costs and satisfy customer demand for precise products, industrial machines’ motion generation is important in improving machine motion precision while using less energy. This study presents a coverage motion energy optimization which is generated by linear interpolation of each segment described by the fourth-order motion profile. The phase changes in the profile are attained with continuity of machine kinematic limits jerk, acceleration, and velocity, which are …


Evaluation Of Thermal And Emission Performances Of Briquettes Produced From Carbonized Corn Cob And Corn Husk, Karina S. Motani Jun 2025

Evaluation Of Thermal And Emission Performances Of Briquettes Produced From Carbonized Corn Cob And Corn Husk, Karina S. Motani

Tanzania Journal of Engineering and Technology (TJET)

The Mozambican agro-industrial sector relies heavily on various crops, with maize being the most significant. During processing, substantial waste is generated, which is often discarded as organic matter or burned, contributing to environmental pollution and the loss of potential energy resources. This study evaluated the thermal and emission performance of briquettes made from carbonized corn cob (CCC) and carbonized corn husk (CCH), using cashew nut skin as a binder for clean cooking applications. The briquettes were assessed against firewood and charcoal as control fuels, focusing on several energy performance parameters: water boiling time (WBT), combustion index (CI), thermal efficiency (TE), …


Comprehensive Review Of Sensible Thermal Storage Systems For Cooking Applications, Anna K. Shariishoy Jun 2025

Comprehensive Review Of Sensible Thermal Storage Systems For Cooking Applications, Anna K. Shariishoy

Tanzania Journal of Engineering and Technology (TJET)

This paper reviewed the sensible thermal storage systems specifically designed for cooking applications. The review focuses on the characteristics of storage materials, their practical applications, and the overall performance of the systems. The review consolidated an array of experimental and numerical research published across various sources such as journals, conferences, books, online resources, and professional reports. A systematic review is used to reach the conclusion of this paper. Significant findings from this study include the wide range of storage capacities attained from small-scale systems that can store ~1–5 MJ of energy for a single meal to bigger systems that can …


Development And Experimental Validation Of A Non-Invasive Blood Group Detection System, Nurath K. Nurudini Jun 2025

Development And Experimental Validation Of A Non-Invasive Blood Group Detection System, Nurath K. Nurudini

Tanzania Journal of Engineering and Technology (TJET)

An individual's blood group consists of red blood cell antigens whose composition is determined by protein presence, antigen structure, and gene series. Persons aged above six months have significant anti-A and/or anti-B in their serum. During transplantation and transfusion, ABO blood group identification is the most essential factor. The conventional method involves drawing blood samples from patients, and the blood group is determined based on the antigen-antibody reaction. This method consists of adding chemical reagents. However, this requires time of operation, and throughput analysis is high, and the process is also challenging to interpret. Accurate and rapid identification of blood …


The Importance Of The Analog-To-Digital Converter In The Measurement System, Aliev Ravshan, Anvar Djalilov Jun 2025

The Importance Of The Analog-To-Digital Converter In The Measurement System, Aliev Ravshan, Anvar Djalilov

Chemical Technology, Control and Management

At the moment, many scientific researches are being conducted all over the world on the economical use of water and energy resources. Most of the scientific research works are aimed at improving measurement techniques and technologies, that is, increasing their accuracy. With this in mind, a high-precision analog-to-digital converter due to its unique metrological and technical characteristics was studied in this research paper. As a result of the study, it became clear that the use of a small-sized, high-precision sigma-delta analog-to-digital converter in modern measuring technology has a positive effect on its accurate and efficient operation.


Algorithms For Making Control Systems Based On Neural Network Technology To Automate Dynamic Plants, Jasur Sevinov, Abdishukurov Maqsudovich Shavkat Jun 2025

Algorithms For Making Control Systems Based On Neural Network Technology To Automate Dynamic Plants, Jasur Sevinov, Abdishukurov Maqsudovich Shavkat

Chemical Technology, Control and Management

This paper examines the stages of multilayer neural network technology for the control and identification of dynamic systems. It is seen many ways to use multilayer neural networks in control systems. Neural controllers are based on several models and algorithms. Examples of such algorithms include the predictive model-based control algorithm, the Narma-L2 control algorithm, and the benchmark model-based control algorithm. These controllers illustrate various general ways to use multilayer neural networks in control systems. Common, standard linear control architectures have been proposed for many neural controllers.


Development Of An Ann-Based Predictive Model For The Efficient Treatment Of Industrial Wastewater, Alisher Khudoyberdi Ugli Rakhimov, Hasan Siddiq Ugli Murodov, Farrukh Bakhtiyorovich Igitov, Shuhrat Ahmadjonovich Mutalov, Jaloliddin Abdurazzakovich Eshbobaev Jun 2025

Development Of An Ann-Based Predictive Model For The Efficient Treatment Of Industrial Wastewater, Alisher Khudoyberdi Ugli Rakhimov, Hasan Siddiq Ugli Murodov, Farrukh Bakhtiyorovich Igitov, Shuhrat Ahmadjonovich Mutalov, Jaloliddin Abdurazzakovich Eshbobaev

Chemical Technology, Control and Management

The effective removal of free chlorine ions from industrial wastewater is critical to ensure process safety, minimize equipment corrosion, and protect aquatic environments. In this study, a laboratory-scale activated carbon filtration system was developed and tested to treat chlorine-contaminated water collected from sludge collectors at industrial facilities. A total of 200 experimental trials were conducted under varied operational conditions, including changes in flow rate, initial chlorine concentration, pressure, pH, temperature, and activated carbon dosage. The resulting dataset was used to train a predictive model based on a feedforward backpropagation artificial neural network (ANN) implemented in MATLAB. The ANN model demonstrated …


Adaptive Control Of Air Purification Processes In Industrial Painting Workshops: A Review Of Scientific Literature, N.A Kabulov, Sh. Mamatbekov Jun 2025

Adaptive Control Of Air Purification Processes In Industrial Painting Workshops: A Review Of Scientific Literature, N.A Kabulov, Sh. Mamatbekov

Chemical Technology, Control and Management

This article examines modern approaches to adaptive control of air purification processes in industrial facilities, particularly in paint shops for parts coating. The relevance of the study is driven by the need to enhance air purification efficiency, ensure worker safety, and comply with environmental regulations. The paper analyzes adaptive control methods, including the use of neural networks, machine learning, and adaptive control algorithms, which enable real-time optimization of purification systems. Special attention is given to the utilization of sensor data for predicting pollution levels and automatically adjusting purification parameters. The article also discusses the advantages and limitations of implementing adaptive …


Predicting The Influence Of Aggregate Size And Distribution On Cementitious Concrete Properties: A Review, Innocent J. Macha Jun 2025

Predicting The Influence Of Aggregate Size And Distribution On Cementitious Concrete Properties: A Review, Innocent J. Macha

Tanzania Journal of Engineering and Technology (TJET)

Cement concrete has been in use for centuries as one of the primary construction materials. Its demand in the construction industry is expected to continue for several centuries before the full development of alternative products. However, one of the main areas of research interest is understanding how its constituents can be tailored to make its properties predictable to reduce risks associated with structural failures, reconstruction and reduced durability. These hindrances associated with cementitious concrete result from several attributes, including constituent material characteristics, mixing ratios and workmanship. Understanding the predictability of cement concrete properties requires computer modelling tools to provide reliable …


Towards Future Sustainable Infrastructure: The Role Of Technical Audit In Tanzania’S Public Works, George C. Haule Jun 2025

Towards Future Sustainable Infrastructure: The Role Of Technical Audit In Tanzania’S Public Works, George C. Haule

Tanzania Journal of Engineering and Technology (TJET)

This study aimed to investigate the vital role and impact of technical audits in promoting sustainable infrastructure development in Tanzania. The role and effects of technical audits in long-term infrastructure development were studied using a mixed-methods approach with both quantitative and qualitative parts. Data were collected through analysis of technical audit documentation, a semi-structured questionnaire, and stakeholder interviews. The study revealed the various dimensions of infrastructure investment projects, including initiation and planning, design, procurement of contractors and consultants, contract management, environment, health, and safety. The technical audit findings reported weaknesses or non-performance issues in infrastructure planning at the national level …


Root Cause Analysis Of Performance Degradation For An Xyz Thermal Power Plant In Tanzania, Simon I. Marandu Jun 2025

Root Cause Analysis Of Performance Degradation For An Xyz Thermal Power Plant In Tanzania, Simon I. Marandu

Tanzania Journal of Engineering and Technology (TJET)

Thermal power plants in Tanzania have been experiencing performance degradation, typically arising from component and subsystem failures, which contribute to power system instability and unreliability. This paper presents a case study of the root causes of performance degradation of an XYZ thermal power plant. The study was conducted by reviewing plant documentations, including maintenance and operational data logbooks, and by standardising the approach through the adoption of ISO 14224:2016 for maintenance and reliability data exchange. Data evaluation was carried out using principal component analysis and scree plot analytical techniques to enhance the depth and accuracy of root cause identification. Additionally, …


Effects Of Cutting Conditions On Tool Temperature And Material Removal Rate In Turning Operations, Simon I. Marandu Jun 2025

Effects Of Cutting Conditions On Tool Temperature And Material Removal Rate In Turning Operations, Simon I. Marandu

Tanzania Journal of Engineering and Technology (TJET)

Cutting conditions in manufacturing processes have effects on tool temperature and material removal rate. The objective of this study was to investigate the effects of cutting conditions namely spindle speed, feed rate, depth of cut and tool nose radius on tool temperature and material removal rate in turning operations. A total of 81 experiments were conducted to measure tool temperature and material removal rate in order to determine the effects of cutting conditions on tool temperature and material removal rate using ANOVA and regression analysis. The results show that tool nose radius, depth of cut, and spindle speed are significant …


Performance Dynamics Of Activated Carbon-Methanol Pair In Adsorption Refrigeration Systems, Ibrahim J. Mwasubila Jun 2025

Performance Dynamics Of Activated Carbon-Methanol Pair In Adsorption Refrigeration Systems, Ibrahim J. Mwasubila

Tanzania Journal of Engineering and Technology (TJET)

Adsorption refrigeration systems have shown potential for addressing the adverse effects of traditional compressor-based refrigeration systems. Adsorption refrigeration systems that utilise activated carbon and methanol demonstrate good performance, especially at temperatures below 0 °C. This combination significantly improves the cooling performance of the system, making it a dependable option for freezing applications. Despite having the potential to meet cooling demand and be eco-friendly, the adsorption refrigeration system has several drawbacks that hinder its commercialisation. This paper discusses the properties of the activated carbon methanol pair in the adsorption refrigeration system. The focus is on the desorption temperature, thermal stress, repeatability …


Optimizing The Processing Temperature For Synthesis Of Silver Nanoparticles Within Cellulose-Wool Keratin Supramolecular Matrix Using Butylmethylimmidazolium Chloride Ionic Liquid, Ngesa E. Mushi Jun 2025

Optimizing The Processing Temperature For Synthesis Of Silver Nanoparticles Within Cellulose-Wool Keratin Supramolecular Matrix Using Butylmethylimmidazolium Chloride Ionic Liquid, Ngesa E. Mushi

Tanzania Journal of Engineering and Technology (TJET)

To date, the synthesis of silver nanoparticles on the surface of cellulose and wool keratin biopolymer, while dissolved in ionic liquid, is attractive because of its biomedical potential. However, the optimal processing temperature for the nanoparticle formation is unclear. The previously reported temperature of approximately 120°C gives unpredictable results. The current study employs a combination of 50% cellulose and 50% keratin, along with 69 mg of silver chloride, in Butylmethylimidazolium Chloride BMImCl ionic liquid, using a single-pot process to produce a supramolecular film via non-derivatized mechanochemical interactions. The primary objective is to experimentally establish the processing temperature to achieve stable …


Magnetic Nanoparticles: Synthesis And Applications In Life Sciences, Kishore Chand, Erick Salvador Vasquez Jun 2025

Magnetic Nanoparticles: Synthesis And Applications In Life Sciences, Kishore Chand, Erick Salvador Vasquez

Chemical and Materials Engineering Faculty Publications

Magnetic nanoparticles (MNPs) are multifunctional materials with superparamagnetic properties and tunable surface chemistries, making them valuable across diverse fields, such as biomedicine, environmental remediation, and agriculture. This review examines recent advancements in MNP synthesis, encompassing chemical, physical, and environmentally friendly methods while highlighting improvements in size, morphology, and composition control that enhance application-specific performance and environmental sustainability. The review discusses various architectures, including single-core, core–shell, hybrid composites, and stimuli–responsive systems, with an emphasis on their stability, scalability, and functionalization potential. In biomedical applications, MNPs show promise in targeted drug delivery, magnetic hyperthermia, and magnetic resonance imaging contrast enhancement, where biocompatibility, …


Vacuum Consistent Electrochemistry In Ionic Liquid Combined With Oxide Epitaxy, Yuji Matsumoto Jun 2025

Vacuum Consistent Electrochemistry In Ionic Liquid Combined With Oxide Epitaxy, Yuji Matsumoto

Journal of Electrochemistry

We introduce our state-of-the art of “vacuum consistent electrochemistry” to an investigation of the interfaces between oxides and ionic liquid (IL). Pulsed laser deposition (PLD) has been one of the powerful and sophisticated techniques to realize nanoscale preparation of high-quality epitaxial oxide thin films. On the other hand, electrochemistry is a simple, very sensitive, and non-destructive analysis technique for solid-liquid interfaces. To ensure the reproducibility in experiment of the interfaces of such epitaxial oxide films, as well as bulk oxide single-crystals, with IL, we employ a home-built PLD-electrochemical (EC) system with IL as an electrolyte. The system allows one to …


Pm Irras Studies Of Organized Molecular Films At A Gold Electrode Surface, Zhang-Fei Su, Ai-Cheng Chen, Jacek Lipkowski Jun 2025

Pm Irras Studies Of Organized Molecular Films At A Gold Electrode Surface, Zhang-Fei Su, Ai-Cheng Chen, Jacek Lipkowski

Journal of Electrochemistry

This feature article illustrates the potential of polarization modulation infrared reflection absorption spectroscopy (PM IRRAS) to provide molecular-level information about the structure, orientation and conformation of constituents of thin films at electrode surfaces. PM IRRAS relies on the surface selection rules stating that the p-polarized IR beam is enhanced, while the s-polarized beam is attenuated at the metal surface. The difference between p- and s-polarized beams eliminates the background of the solvent and provides IR spectra at a single electrode potential. In contrast, two other popular in situ IR spectroscopic techniques, namely, subtractively normalized interfacial Fourier transform infrared spectroscopy (SNIFTIRS) …


Ambient Co2 Capture And Valorization Enabled By Tandem Electrolysis Using Solid-State Electrolyte Reactor, Yan-Bo Hua, Bao-Xin Ni, Kun Jiang Jun 2025

Ambient Co2 Capture And Valorization Enabled By Tandem Electrolysis Using Solid-State Electrolyte Reactor, Yan-Bo Hua, Bao-Xin Ni, Kun Jiang

Journal of Electrochemistry

Electrocatalytic carbon dioxide reduction is a promising technology for addressing global energy and environmental crises. However, its practical application faces two critical challenges: the complex and energy-intensive process of separating mixed reduction products and the economic viability of the carbon sources (reactants) used. To tackle these challenges simultaneously, solid-state electrolyte (SSE) reactors are emerging as a promising solution. In this review, we focus on the feasibility of applying SSE for tandem electrochemical CO2 capture and conversion. The configurations and fundamental principles of SSE reactors are first discussed, followed by an introduction to its applications in these two specific areas, …


Cyclic Combustion Pressure Dynamics Of A Diesel Engine Operating On Waste Frying Oil Biodiesel Blends Using Wavelets, Shady Elmozy, Ahmed Khaira Dr., Elshenawy Elshenawy Prof. Dr., Ali Mohamed Dr., Medhat Elkelawy Prof. Dr, Jun 2025

Cyclic Combustion Pressure Dynamics Of A Diesel Engine Operating On Waste Frying Oil Biodiesel Blends Using Wavelets, Shady Elmozy, Ahmed Khaira Dr., Elshenawy Elshenawy Prof. Dr., Ali Mohamed Dr., Medhat Elkelawy Prof. Dr,

Journal of Engineering Research

This paper investigates the cyclic combustion pressure dynamics of a single-cylinder diesel engine burning waste frying oil biodiesel blends, employing statistical analysis and continuous wavelet transform (CWT) to evaluate combustion stability. Experiments were conducted at a constant engine load (90%) and speed (1500 rpm), with in-cylinder pressure data collected over 400 consecutive cycles for conventional diesel (RD) and biodiesel blends (UB10, UB30, UB50). Results demonstrate that biodiesel blends marginally reduce average peak cylinder pressure (PP) by 0.3–3.8% while lowering PP variability, evidenced by declining coefficients of variation (COV-PP: 1.27–1.48%), attributed to biodiesel’s elevated viscosity promoting consistent fuel-air mixing. Conversely, mean …


Combustion Characteristics And Cycle-To-Cycle Variations In A Diesel Generator Fueled With Used Frying Oil Biodiesel Blends, Shady Elmozy, Ahmad Khira Dr., E. A. El Shenawy Prof. Dr., Medhat Elkelawy Prof. Dr, Eng. Jun 2025

Combustion Characteristics And Cycle-To-Cycle Variations In A Diesel Generator Fueled With Used Frying Oil Biodiesel Blends, Shady Elmozy, Ahmad Khira Dr., E. A. El Shenawy Prof. Dr., Medhat Elkelawy Prof. Dr, Eng.

Journal of Engineering Research

This paper investigates the combustion characteristics and cycle-to-cycle variations in a stationary direct-injection diesel generator fueled with biodiesel derived from used frying oil (UFO) blended with conventional diesel. Used frying oil methyl ester (UFOME), referred to as UB100, was produced through a single-step alkali transesterification process and blended with diesel fuel in varying proportions (UB10, UB20, UB30, UB40, and UB50). Experiments were conducted on a single-cylinder, naturally aspirated diesel engine operating at a constant speed of 1500 rpm under five different load conditions: 0%, 25%, 50%, 75%, and 90%. In-cylinder pressure data from 400 consecutive cycles were analyzed to determine …


A Comprehensive Review Of Natural Gas-Diesel Dual-Fuel Engines: Efficiency, Emissions, And Engine Performance, Medhat Elkelawy Prof. Dr, Eng., E. A. El Shenawy Prof. Dr., Hagar Alm-Eldin Bastawissi Prof. Dr. Eng., Mohamed Mostafa Shafey Eng Jun 2025

A Comprehensive Review Of Natural Gas-Diesel Dual-Fuel Engines: Efficiency, Emissions, And Engine Performance, Medhat Elkelawy Prof. Dr, Eng., E. A. El Shenawy Prof. Dr., Hagar Alm-Eldin Bastawissi Prof. Dr. Eng., Mohamed Mostafa Shafey Eng

Journal of Engineering Research

Natural gas (NG) diesel dual-fuel systems have emerged as a promising advancement in internal combustion engine (ICE) technology, offering significant potential for reducing emissions, while maintaining high fuel efficiency and performance standards. This review critically examines the combustion characteristics, operational performance, emissions mitigation potential, and the engineering challenges associated with engine modifications and fuel system compatibility. Furthermore, the role of dual-fuel technology within broader global climate change mitigation strategies is explored. Extensive evidence from the literature confirms that NG-diesel dual-fuel engines can achieve substantial reductions in nitrogen oxides (NOₓ) emissions up to 53% particulate matter (PM) by over 60%, and …


Experimental Investigation On The Effect Of Using Gasoline With Commercial Additives On Spark Ignition Engines Performance And Emissions Characteristic, Medhat Elkelawy Prof. Dr, Eng., E. A. El Shenawy Prof. Dr., Hagar Alm-Eldin Bastawissi, Emad Mostafa Eng. Jun 2025

Experimental Investigation On The Effect Of Using Gasoline With Commercial Additives On Spark Ignition Engines Performance And Emissions Characteristic, Medhat Elkelawy Prof. Dr, Eng., E. A. El Shenawy Prof. Dr., Hagar Alm-Eldin Bastawissi, Emad Mostafa Eng.

Journal of Engineering Research

Gasoline is the primary source of energy in combustion engines, despite some drawbacks, such as knocking inside the engine, incomplete combustion, and the production of high emissions. The main trend has been toward the use of chemical additives as improvers, including oxidizing additives and aromatic hydrocarbon compounds. Both additives have an effect on the combustion process. Oxidizing additives improve the combustion process inside the chamber by adding additional oxygen to the fuel, which helps accelerate flame propagation, such as ethanol and oleo-octane plus. On the other hand, aromatic additives are used to increase the octane number, which in turn enhances …


Investigation Of Activated Carbon From Rice Waste Using Superheated Steam, Wael Abdelmoez, Jehan Tolba, Hiroyuki Yoshida, Sherif Ahmed Kamal Jun 2025

Investigation Of Activated Carbon From Rice Waste Using Superheated Steam, Wael Abdelmoez, Jehan Tolba, Hiroyuki Yoshida, Sherif Ahmed Kamal

Journal of Engineering Research

Activated carbon is essential in many industries and applications, especially in removing odor and color in sewage treatment plants. The most common activated carbon used is generated from coconut shells, which are difficult to obtain in many countries, especially in the Middle East, as coconut trees do not grow in the environment there; therefore, it was essential to find local alternatives from the national agricultural waste. This study presents the investigation of activated carbon from rice husks using superheated steam in a rotary kiln. The effect of thermal activation on the porosity of the activated rice husks at different temperatures …


Reduction Of Volatile Acidity Of Grape Wines By Immobilized Lipase, Azamhon Kh. Khasanov, Barno A. Abdullaeva, Xasan T. Khasanov Jun 2025

Reduction Of Volatile Acidity Of Grape Wines By Immobilized Lipase, Azamhon Kh. Khasanov, Barno A. Abdullaeva, Xasan T. Khasanov

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this work is to study the enzymatic transformation of acetic acid into ethyl acetate by immobilized lipases of the fungus Rhizopus microsporus UzLT-1 obtained on the basis of silica gel and phosphatidylethanolamine to reduce the content of volatile acids in grape wines. In the work, a preparation of lipase from the fungus Rhizopus microspores was used. Lipolytic activity was measured by photocolorimetric method using rhodamine 6G as a chromophore agent. The catalytic property of lipolytic enzymes from the fungus Rh.microsporus immobilized on the surface of silica gel coated with polyamides and modified cephalin in aqueous-alcoholic media was …


High-Frequency Impedance Spectroscopy: Measurement Reproducibility, Electromagnetic, And Ionic Effects In Cylindrical Lithium-Ion Cells, Matthew R. King, Paul T. Coman, Rafid Mollah, Md Rayhan Khan, Saranraj Karuppuswami, Taylor R. Garrick, Ralph E. White Jun 2025

High-Frequency Impedance Spectroscopy: Measurement Reproducibility, Electromagnetic, And Ionic Effects In Cylindrical Lithium-Ion Cells, Matthew R. King, Paul T. Coman, Rafid Mollah, Md Rayhan Khan, Saranraj Karuppuswami, Taylor R. Garrick, Ralph E. White

Faculty Publications

Accurate high-frequency electrochemical impedance spectroscopy (HF EIS) is critical for understanding lithium-ion battery (LIB) behavior under AC perturbations, relevant to electric vehicle systems and charging infrastructure. However, measurements at high frequencies are often distorted by external electromagnetic interference, poor contact quality, and wiring artifacts. This study investigates four experimental testbench configurations for HF EIS of cylindrical LIBs, highlighting the impact of contact resistance, Faraday shielding, wire twisting, and calibration. A coupled electrochemical-electromagnetic model is developed to isolate and analyze the skin effect and frequency-dependent electrolyte conductivity. Results show that spot-welded connections, twisted and shielded wiring, and calibration within a Faraday …


3d Nano-Architected Polymer Shell Enables Reconfigurable Stabilized Blue Phase Soft Crystals, Sephideh Norouzi, Yazael R. Morales-Flores, Tadej Emersic, Jeremy Money, Otillo E. Rodriguez-Lopez, Andrew Casale, Juan J. De Pablo, Jose A. Martinez-Gonzalez, Monirosadat Sadati Jun 2025

3d Nano-Architected Polymer Shell Enables Reconfigurable Stabilized Blue Phase Soft Crystals, Sephideh Norouzi, Yazael R. Morales-Flores, Tadej Emersic, Jeremy Money, Otillo E. Rodriguez-Lopez, Andrew Casale, Juan J. De Pablo, Jose A. Martinez-Gonzalez, Monirosadat Sadati

Faculty Publications

Blue phases (BPs), formed through the self-assembly of chiral liquid crystal molecules into 3D nanolattices with cubic symmetries, exhibit dynamic photonic bandgaps in the visible spectrum, offering transformative opportunities for advanced optical circuits, sensing and communication technologies. However, their thermal stability is restricted to a narrow temperature range (0.5–1.0 K), limiting practical applications. Polymer stabilization of bulk BPs has extended thermal stability but often compromises the dynamic behavior essential for fast-response functionalities. Here, experimental and computational approaches are integrated to investigate the effect of curvature and interfacial interactions on BP polymer stabilization. It is demonstrated that photo-polymerization of reactive monomers …


Work In Progress: Exploring The Impact Of International Experiences On The Development Of Students’ Entrepreneurial Mindset, Olgha Bassam Qaqish, Marcia Pool, William H. Pennock, Erick Salvador Vasquez, Fahmidah Ummul Ashraf Jun 2025

Work In Progress: Exploring The Impact Of International Experiences On The Development Of Students’ Entrepreneurial Mindset, Olgha Bassam Qaqish, Marcia Pool, William H. Pennock, Erick Salvador Vasquez, Fahmidah Ummul Ashraf

Chemical and Materials Engineering Faculty Publications

International experiences, including collaborative online international learning (COIL) experiences that naturally increase accessibility, are of interest to many undergraduate students. These experiences provide educators a unique opportunity to develop a student's entrepreneurial mindset (EM). Additionally, hands-on experiences aligned with the National Academy of Engineering’s (NAE) grand challenge themes (Sustainability, Security, Health, and Joy of Living) support connections between the experience, disciplinary knowledge, multicultural awareness, and EM. Through this Work-in-Progress (WiP) study, we seek to answer: 1) How do international experiences influence undergraduate science and engineering students’ EM, and 2) How does the international experience modality (i.e., study abroad or COIL) …


Understanding The Effects Of Binder Dissolution Dynamics On The Chemistry And Performance Of Lithium–Sulfur Batteries, Saheed A. Lateef, John Chmiola, Fabio Albano, William E. Mustain, Golareh Jalilvand Jun 2025

Understanding The Effects Of Binder Dissolution Dynamics On The Chemistry And Performance Of Lithium–Sulfur Batteries, Saheed A. Lateef, John Chmiola, Fabio Albano, William E. Mustain, Golareh Jalilvand

Faculty Publications

Lithium–sulfur batteries (LSBs) are promising next-generation energy storage devices due to their higher theoretical specific energy and lower cost compared to conventional Lithium-ion batteries. However, their practical implementation has been hindered by severe performance degradation during extended cycling, primarily driven by shuttling of soluble sulfur discharge products (polysulfides) between the cathode and anode leading to capacity loss. In this work, we investigate the impact of selected binders and solvents, highlighting the effect of the dissolution process of the binder in solvent, on the structural properties and electrochemical performance of sulfur cathode. It is demonstrated for a variety of binders that …