Department Of Mechanical Engineering Research Articles

Characterization of Rate of Injection for Low Carbon Fuels in the Common-Rail Direct Injection System

Article Characterization of Rate of Injection for Low Carbon Fuels in the Common-Rail Direct Injection System Simon LeBlanc, Binghao Cong, Xiao Yu, and Ming Zheng * Department of Mechanical, Automotive and Materials Engineering, University of Windsor, 401 Sunset Avenue, Windsor, ON N9B 3P4, Canada * Correspondence: mzheng@uwindsor.ca Received: 26 March 2025; Revised: 8 April 2025; Accepted: 25 April 2025; Published: 30 April 2025 Abstract: Internal combustion engines (ICEs) powered by liquid fuels remain the dominant powertrain system for heavy-duty road transportation, benefiting from the high energy density, ease of storage and transportation, and relatively low refueling pressure of traditional liquid hydrogen carbon fuel. However, concerns over tailpipe emissions and greenhouse gas (GHG) effects have driven the search for alternative fuels with lower carbon footprints. ICEs offer a key advantage during this transition, as they can operate on a variety of fuels, enabling a flexible approach to reducing harmful emissions and GHG while maintaining reliable power output. Alternative liquid fuels, such as dimethyl ether (DME), have shown great potential in mitigating environmental impacts while ensuring sufficient engine performance. However, the significantly different physical and chemical properties of renewable fuels necessitate the adoption of tailored combustion strategies to ensure optimal engine operation. In particular, the fuel injection strategy plays a pivotal role in governing the combustion process, as it directly influences fuel-air mixing, ignition characteristics, and hence, the combustion efficiency. Therefore, detailed characterization of the fuel injection process (rate of injection (ROI) profiles, injection delay, and injection quantities) is necessary for research and development of advanced combustion strategies. In this study, the ROI profiles for diesel, DME and polyoxymethylene dimethyl ethers (OME3) were measured using the Bosch long tube method, with diesel severed as the reference fuel. Comparative tests were conducted under varying injection pressures (300 bar to 900 bar) and injection durations (0.3 ms to 3 ms) to investigate the influence of fuel properties on ROI profiles. The results revealed that all three fuels exhibited comparable ROI at injection durations below 700 µs. However, at longer injection durations and higher pressures, significant differences emerged. At a 3 ms injection duration, DME consistently showed the lowest steady-state ROI, while OME3 exhibited the highest across all injection pressures. Furthermore, the discharge coefficient (Cd) increased with injection pressure and converged across three fuels at higher pressures. This indicated that, under those conditions, fuel density became the dominant factor influencing ROI, hence the injection quantities.

Retrofitting the MyFord 254S lathe with PLC and SCADA control for spindle motor speed regulation

The MyFord 254S lathe in the Mechanical Engineering Department of Politeknik Negeri Manado (Polimdo) will be retrofitted with new technology or features into the old system, becoming semi-automatic, combining PLC and SCADA technology. This research uses the experimental method, where the author designs by creating a ladder diagram in CX-Programmer software and uploading it to the Omron PLC, whose output will be connected to the Variable Frequency Drive (VFD) to control and drive a 3-phase induction motor as a spindle driver with a single-phase AC input voltage on the VFD. It creates a control design in NB-Designer software to be uploaded to the Omron HMI as a SCADA control display. The ladder diagram programming on the Omron PLC designed with CX-Programmer software includes motor frequency options of 15 Hz (602 rpm), 20 Hz (802 rpm), 25 Hz (1003 rpm), 30 Hz (1204 rpm), 35 Hz (1404 rpm), 40 Hz (1605 rpm), 45 Hz (1806 rpm), and 50 Hz (2006 rpm). As a result of the addition of PLC and SCADA to this lathe machine, the spindle speed can be easily adjusted compared to manual settings, as it only requires pressing on the HMI. Contribution to Sustainable Development Goals (SDGs):SDG 9 – Industry, Innovation, and InfrastructureSDG 4 – Quality EducationSDG 12 – Responsible Consumption and Production

Computational Analysis and Optimization of a Crab-Type MEMS Accelerometer for Wide-Range Acceleration Sensing

Aims: This study designs and analysis of a Crab-Type MEMS accelerometer for high-sensitivity applications under extreme acceleration. It evaluates vibration characteristics, sensitivity, and shock resistance through computational simulations, ensuring suitability for automotive, aerospace, and industrial sensing. Study Design: A computational study using COMSOL Multiphysics and MATLAB for design, modelling, and optimization, conducted over six months in the Department of Mechanical Engineering. Methodology: A 3D model of the accelerometer was created, and finite element simulations analysed its natural frequency, displacement sensitivity, and mechanical shock response. Modal analysis determined frequency response, while displacement-to-capacitance conversion evaluated sensitivity. Shock analysis applied impact loads from -30g to +30g, with von Mises stress distribution assessing mechanical stability. MATLAB-based analytical models validated the results. Results: The accelerometer’s natural frequency (~3.40 kHz) ensures stable operation below resonance. Displacement sensitivity showed a linear relationship between acceleration and proof mass displacement, with improved capacitive sensitivity through electrode gap optimization. Shock analysis confirmed structural integrity under high-impact conditions, with rapid stabilization post-impact, making it suitable for crash detection and aerospace navigation. Conclusion: The Crab-Type MEMS accelerometer exhibits high sensitivity, stable frequency response, and strong shock resistance, making it ideal for precision sensing applications. Future experimental validation and material optimization could further enhance real-world performance.

Harnessing Stress: Conventional and Unconventional Strategies for Enhancing Microalgal Productivity in Sustainable Biorefineries

Review Harnessing Stress: Conventional and Unconventional Strategies for Enhancing Microalgal Productivity in Sustainable Biorefineries Chia-En Chuang 1,†, Yu-Han Chien 1,†, Sheng-Yung Lin 1,†, Adi Kusmayadi 2, Jia-Hui Zhou 1, Chiao Ching Chang 1, Chen Rui Zhang 1 and Yoong Kit Leong 1,3,* 1 Department of Chemical and Materials Engineering, Tunghai University, Taichung 407, Taiwan 2 Department of Mechanical Engineering, Politeknik Negeri Indramayu, Indramayu 45252, Indonesia 3 Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung 407, Taiwan * Correspondence: yoongkit1014@thu.edu.tw † These authors contributed equally to this work. Received: 18 January 2025; Revised: 2 March 2025; Accepted: 6 March 2025; Published: 2 April 2025 Abstract: Microalgae are versatile platforms for producing biofuels and high-value metabolites, such as lipids, proteins, and carotenoids. Numerous stress strategies have been adopted to improve microalgal cultivation and biomolecule yield. This review examines how conventional stress factors (light and salinity) and unconventional treatments (electric field treatment) influence microalgal growth and metabolite accumulation. Light intensity, spectrum, and photoperiod significantly affect photosynthesis, biomass yield, and carotenoid biosynthesis, with moderate intensities found to enhance efficiency. However, excessive levels may induce photoinhibition. Salinity stress induces activation of antioxidant systems and lipid accumulation, optimizes biofuel properties. However, excessive high salinity can impair the growth of microalgae. In this review, we focused on the electric field treatment as a potential strategy for enhancing microalgal productivity, representing a major novelty of the study. Unlike traditional stress factors that primarily induce adaptive metabolic shifts, electric field treatment offers a unique and an understudied approach for modulating cellular physiology. Electric treatment technology offers an energy-efficient method for stimulating cell differentiation and enhancing lipid and pigment production while reducing environmental effects. Integrating these stress factors may be an attractive approach for controlling over microalgal metabolism, supporting sustainable and scalable biorefinery applications.

Impact of Student Feedback on Lecturer’s Performance at Rwanda Polytechnic’s Kigali College

This study fills the gap of formal student feedback mechanisms at Rwanda Polytechnic’s Kigali College, more specifically how this gap impacts lecturer performance in the Civil and Mechanical Engineering departments. The Feedback Intervention Theory which focuses on specific and practical feedback informed the study and a quantitative approach was adopted. A total of 90 second year students were selected using stratified random sampling and structured questionnaires were used to collect data. The findings of the study revealed that the students had a positive perception of the performance of the lecturers (overall mean = 3.41) and identified strengths in areas such as organization of the classes (mean = 3.89) and the applicability of the concepts taught in the real world (mean = 3.44). However, there were some weaknesses, such as ambiguity in instructions (mean = 2.96) and lecturers' availability (mean = 3.31). Students agreed with the proposal of implementing an anonymous online feedback system (mean = 4.56), but 64% of them were concerned that it may lead to negative consequences for their grades or relations with the lecturers. The study suggests the development of an anonymous feedback system, increased presence of lecturers, professional training, and the pilot feedback implementation to increase the effectiveness of teaching

Review of Digital Twin in the Automotive Industry on Products, Processes and Systems

Review Review of Digital Twin in the Automotive Industry on Products, Processes and Systems Heli Liu 1,2, Benjamin Zhang 1, Vincent Wu 1,2, Xiao Yang 1,2, and Liliang Wang 1,2,* 1 Department of Mechanical Engineering, Imperial College London, London SW7 2AZ, UK 2 Smart Forming Research Base, Imperial College London, London SW7 2AZ, UK * Correspondence: liliang.wang@imperial.ac.uk Received: 17 February 2025; Revised: 10 March 2025; Accepted: 20 March 2025; Published: 24 March 2025 Abstract: In the era of digital manufacturing, digital technologies are rapidly revolutionising the automotive industry. Among these, the digital twin, an enabling industry 4.0 digital technology first introduced two decades ago, is characterised by the seamless integration of physical and cyber realms. The digital twin is undergoing extensive investigations within the automotive sector, covering various perspectives including design, manufacturing, and application. By leveraging the big manufacturing data captured by spatially distributed sensing networks, the digital twin shows the capacity to create high-fidelity models of actual manufacturing practices, thereby significantly improving the precision and efficiency of production processes. Integrated with other digital technologies such as big data analytics (BDA) and the Internet of Things (IoT), the digital twin mirrors components in the physical world into the virtual environment and facilitates the exchange of real-time information to achieve fully converged cyber-physical spaces. This in turn minimises costs and improves the overall product quality, flexibility of manufacturing processes, and system integration. This work reviewed recent advancements in digital twin applications in the automotive industry focusing on automotive products, manufacturing processes, and manufacturing systems. Insights were provided into the future of digitally enhanced technologies in automotive manufacturing towards digital manufacturing and developing digital product passports (DPPs) for circular economy (CE).

Development of Augmented Reality Applications as Learning media for Machine Assembly and Installation

There are several courses at the State University of Malang, Faculty of Engineering, Mechanical Engineering Department, one of which is Machine Assembly and Installation which studies knowledge related to management, procedures and materials used to assemble and install machines. The learning process is not optimal because there is no demonstration of the use of lifting aircraft due to limited availability. Therefore, learning media innovations are needed that aim to contain comprehensive material and visualizations lifting aircraft in 3D. Digital AR learning media that is easy to operate by students flexibly. Developing augmented reality-based learning media on lifting aircraft for engine assembly and installation courses and testing its feasibility are the objectives of this study. This development uses the ADDIE model. The results of this study are as follows: (1) material validation obtained a percentage value of 94.31%, which is classified as very feasible; (2) media expert validation showed the feasibility level with a percentage of 93.75%; and (3) the results of small group trials showed a very feasible level with a percentage of 90.12%. The implication of this research is to increase learning effectiveness, increase student learning motivation and facilitate teaching lecturers in the knowledge transfer process.

Experimental Investigation of the Effect of Seawater on Glass and Carbon Fiber Composites via Mechanical Characterization

Since composite materials are light and corrosion-resistant, they have replaced many traditional materials in the aviation and marine industries. Composite materials have the advantages of a much higher strength–weight ratio, lower maintenance requirements, and the ability to form complex shapes, such as bodies, compared to carbon steel. In this study, the mechanical properties of glass fiber reinforced (GFRP) and carbon fiber reinforced (CFRP) composite materials were investigated in marine applications in which composite materials had been used. In this study, 0/90 oriented twill weave eight-ply GFRP and eight-ply CFRP composite materials were used, incorporating the hand lay-up method and hot-pressing method. Seawater was taken from the Aegean Sea, Izmir Province (Balçova/İnciraltı), and had an average temperature of 22.43 °C. This seawater was kept in different containers for 30 days and 60 days (a total of 1440 h of keeping in seawater) with the intent to test the GFRP and CFRP composite samples separately. The produced CFRP and GFRP sheets were then cut with a wet (circular) saw in accordance with the standard procedure in the Composite Research and Testing Laboratory of the Dokuz Eylul University Department of Mechanical Engineering. Moisture retention percentages and Charpy impact tests were carried out. Then, three-point bending tests were carried out according to TS EN ISO 14125. The damage in the material was examined using a ZEISS Stereo Discovery.V12 imaging microscope (Oberkochen, Germany). The mechanical properties of CFRP- and GFRP-reinforced composite samples before and after aging were investigated using the Charpy impact test and three-point bending test. Then, the effects of the seawater environment on the mechanical properties of the CFRP and GFRP composite materials were evaluated by comparing the results. The aim was to better understand what kind of damage would occur in GFRP and CFRP composite materials given the effects of seawater and at what stages changes would occur in the mechanical properties of these materials. Moisture retention rates (%) in the tested samples after the Charpy impact test were 2.56% in GFRP and 0.47% in CFRP after 30 days. In the tested samples after the three-point bending test, these values were 1.41% in GFRP and 0.31% in CFRP after 30 days. Subsequent to the Charpy impact tests, the fracture toughness values of the CFRP samples tested at the 30 J impact energy level before aging in seawater conditions for 30 days or 60 days were found to be increased by 15.79% and 21.08%, respectively. The fracture toughness values of the GFRP tested at the 30 J impact energy level in dry conditions and kept in seawater for 30 days or 60 days were found to be 27.69% and 29.23%, respectively. The energy absorbed during the impact tests by the GFRP samples was higher than in the CFRP samples. This showed that the GFRP samples were more brittle. Subsequent to the three-point bending tests, the CFRP composite samples kept in seawater for periods of 30 days and 60 days showed changes in the modulus of elasticity of 7.48% and 7.46%, respectively, compared to the dry samples. The GFRP composite samples kept in seawater for periods of 30 days and 60 days showed changes in the modulus of elasticity of 7.015% and 11.53%, respectively, compared to the dry samples. The change in the modulus of elasticity was less in the CFRP samples than in GFRP. All of these results showed that the mechanical properties of CFRP were better than those of GFRP.

Study of The Influence of Extract Cocoa Pods (Theobroma Cacao) as a Preservative Ingredient on Mahoni Woods (Swietenia Mahogany) Through Cold Soaking on Mechanical Properties

An attempt has been made to extend the service life of mahogany wood (Swietenia mahogany) by preserving it. The purpose of this study was to determine the mechanical properties of mahogany wood after cold soaking with preservatives of cocoa pods extract (Theobroma cacao). This research uses an experimental method of cold soaking which is carried out in the Material Testing Laboratory of the Mechanical Engineering Department of Padang State Polytechnic. The preservation process used cacao pod extract preservative solution at concentrations of 0%, 3%, 6%, 9%, 12%, and 15%. The observed responses were the preservative retention values and mechanical properties (compressive strength parallel to the fiber direction, flexural strength, and surface hardness) of the wood. The preservation method applied was cold soaking for 120 hours. The increase in retention value was directly proportional to the increased concentration of extract added. The improved properties of wood (compressive strength in the grain direction and flexural strength) also increased with increasing extract concentration. The results obtained showed that the highest value was obtained at a 15% concentration of the added extract with a retention of 7.6078 kg/cm2, a compressive strength parallel to the fiber of 227.92 kg/m2, and a flexural strength of 387.82 kg/m2. This data shows that cocoa pods extract has the potential to be used as an environmentally friendly wood preservative.

Corrigendum

Oleiwi, A. H., Jabur, A. R., Alsalhy, Q. F., Zeinedini, A. "Crude Oil Desulfurization by Polystyrene/Graphene Nanocomposite Membranes", Periodica Polytechnica Chemical Engineering, 2025.https://doi.org/10.3311/PPch.38227When the above article was first published online the fourth affiliation was incorrect. This has now been corrected in the online version. The correct version of the fourth affiliation is published here. 4 Department of Mechanical Engineering, Kermanshah University of Technology, Kermanshah, Iran

The Effect of Implementation Project-Based Learning Model on Vocational Students' Machining Learning Outcomes

This study aims to analyze the improvement of the learning process, competencies achieved by students, and student learning outcomes in the implementation of the Conventional Lathe Machining Technique learning process with a sample of class XI TM 4 Mechanical Engineering Department of SMK Negeri 3 Yogyakarta through the treatment of implementing the Project-Based Learning learning model. This research uses the Classroom Action Research (CAR) method. This research will be conducted in two cycles; the first cycle will include one meeting, and the second cycle will consist of two sessions to evaluate learning to determine the learning process results. The cycle of PTK stages rotates from one cycle to the next. It begins with planning (plan), action (action), observation of the action taken, and reflection (reflection). The results showed that the quality of the learning process before being given action was only 48.33% still in the “Fair” category and the learning outcomes in pre-cycle activities the average student score was 66.51 with 18.75% classical completeness which was still relatively low. After the implementation of the project-based learning model, there was an increase in cycle I where the results of the observation of the learning process with a percentage of 75% were in the “Good” category and student learning outcomes also experienced an increase in the average student score of 78.86 with 75% classical completeness. Furthermore, in the learning process of cycle II, there was an increase with a percentage of 91.66% which was included in the “Very Good” category, and at the end of cycle II, the average score increased to 86.05 with classical completeness reaching 100%. Thus, student learning outcomes in cycle II have met the indicators set in this study, namely more than 75% of the students obtained scores above the minimum score, which is ≥ 76.00.

The Synergy of Knowledge, Experience, and Satisfaction in Engineering Education

This study aims to investigate the knowledge mastery, experience, and satisfaction of engineering lecturers at University and Polytechnic in teaching engineering subjects. Using a quantitative approach, data were collected from 248 lecturers across the Civil, Electrical, and Mechanical Engineering departments through a questionnaire. Descriptive statistical analysis via SPSS was employed, analyzing mean scores, Pearson correlations, and regression results. The findings reveal that the lecturers possess a high level of knowledge (mean score = 3.97) in the engineering subjects they teach, particularly in the areas of application (mean score = 4.01) and understanding (mean score = 3.98). Approximately 70.3% of lecturers have adequate teaching experience, which they enhance through peer discussions. Satisfaction levels are also high, with a mean score of 4.12 for job satisfaction and 4.15 for responsibility. The analysis found a weak but positive correlation (0.205) between knowledge mastery and experience, although regression analysis indicated that experience only explained 4.5% of knowledge mastery. In contrast, a strong positive correlation (0.756) was found between knowledge mastery and job satisfaction, with satisfaction accounting for 57.1% of the variation in knowledge mastery. The results suggest that while experience has a limited impact on knowledge mastery, satisfaction plays a significant role, implying that lecturers with greater knowledge of their subjects are more likely to experience higher job satisfaction.

University of Wisconsin-Madison mechanical engineering experiential design project case study

This case study explores the experiential learning course of Interdisciplinary Experiential Design Projects (ME 351/352) within the Mechanical Engineering Department at the University of Wisconsin-Madison. Central to the engineering curriculum, this two-semester capstone sequence integrates human-centered design principles and hands-on learning to bridge academic knowledge with real-world applications. Students carry out client-driven projects, developing technical, communication, and project management skills through iterative design, prototyping, and testing. With active collaboration from faculty, industry sponsors, and peers, the course prepares students for the workforce by addressing the "skills gap" between academic training and industrial demands. Key features include a structured yet flexible course design, stakeholders' analysis, dedicated design spaces, and weekly feedback mechanisms, fostering technical innovation, professional growth, and industry engagement. This study highlights the experiential learning course's value in enhancing student employability while providing industry partners with recruitment opportunities and innovative solutions, it also points out certain challenges and corresponding action plan for continuous course improvement.

DEVICE FOR CALIBRATION OF THE PRESSURE SENSOR OF GRANULAR BULK MATERIALS

According to the plan for the implementation of the scientific and technical work "Experimental and theoretical studies of the influence of the roll of a vertical deep container on the distribution of horizontal pressure of granular bulk material on the walls of the container" (DR No. 0121U112518), which is being carried out at the Department of Mechanical Engineering of ODABA, for further research on the pressure distribution of bulk material, a pneumatic measuring system for measuring pressure of granular material on the vertical walls of storage models was developed. Pressure measurements are indirect - based on the absolute value of the movement of the sensor platform, which perceives the pressure of the bulk material, relative to the sensor body, the amount of pressure of the bulk material on the sensor was estimated. The system is multi-channel, each measuring channel consists of a bulk material pressure sensor, a channel for measuring movement of the pressure sensor platform and a recorder of this movement. The device for calibrating the pressure sensor is designed to obtain the calibration dependence of the output signal (the air pressure in the measurement chamber with pneumatic sieves) from the input signal (the value of the uniformly distributed pressure on the sensor). The device is two connected hydraulic systems filled with water. One of them consists of a pressure chamber with a flexible membrane through which the water pressure is transmitted to the sensor, and a measuring tube with a ruler to measure the water level above the membrane. The second one is a buffer tank for water, connected to the pressure chamber of the first system by a flexible tube and can move in vertical position. Hydrosystems are interconnected, so the both of them have the same water level. The water pressure on the sensor changes by moving the buffer tank up and down. The sensor is made in accordance with the patent of Ukraine for the invention and consists of a housing connected through an annular elastic element to the sensor platform, which perceives the pressure of the bulk material. In order to exclude the impact on the measured pressure by arching in the loose material above the sensor platform, linear displacements of the sensor platform relative to the housing should not exceed 5-8 ?m. Such small movements are measured by a non-contact pneumatic gauge based on a non-differential measuring pneumatic system of the manometric type with a working air pressure in the system of 7.5-10 kPa. Air pressure in the pneumatic system is measured by alcohol manometers. The device is made in the form of a two-branch rack: one branch is a measuring branch, and the other has a screw mechanism for vertical movement of the buffer tank. The accuracy of the pressure assignment on the sensor is ± 0.1 g/cm2, and the measurement of the output signal is ± 0.5 mm

THE APPLICATION OF BIOMASS STOVES AMONG THE BERKAT RAMA FARMER GROUP IN BIBIOSI VILLAGE, ARSO DISTRICT, KEEROM REGENCY

This community service activity aims to introduce biomass stoves to communities in need, particularly those with abundant biomass waste. The biomass stove's performance has already been evaluated through prior research conducted on campus. This community service initiative will be carried out with the Berkat Rama farmer group in Bibiosi Village, a major corn production area near Cenderawasih University in Arso District, Keerom Regency. Based on preliminary site assessments, local farmers reported significant quantities of agricultural waste, specifically corn cobs, left after harvest. This waste has not been optimally utilized by farmers and is typically disposed of by burning. Motivated by this, our community service team from the Department of Mechanical Engineering at Cenderawasih University aims to introduce corn cob-fueled biomass stoves to the local community. The Community Service Program (PKM) was met with strong enthusiasm from participants, who actively engaged in the socialization session through to its conclusion. The community expressed a desire for more frequent activities of this kind to broaden their knowledge and skills, especially regarding appropriate technology applications. The final outcome of this community service is an increase in both knowledge and skills among members of the Berkat Rama farmer group, specifically in the fabrication and operation of the introduced biomass stoves. They also received training in operational safety for biomass stoves. The acquired knowledge and skills are expected to be applied and shared with other community members and farmers in the area.

Analisis Kendala dan Solusi dalam Penerapan Kurikulum Merdeka pada Jurusan Teknik Listrik dan Mesin di SMK PGRI 1 Kota Serang

The implementation of the Merdeka Curriculum in Vocational High Schools (SMK) aims to enhance the quality of vocational education by promoting flexible learning that aligns with industry needs and fosters 21st-century skills. In the Electrical and Mechanical Engineering departments, this curriculum emphasizes project-based learning to develop both technical and soft skills. However, the application of the Merdeka Curriculum at SMK PGRI 1 Kota Serang faces several challenges that need to be addressed for its effective implementation. One of the key challenges is the adaptation of students to new learning methods, particularly those involving independent learning and critical thinking. Additionally, limited time for implementing projects and integrating them into the curriculum often hampers optimal learning outcomes. Teachers also face difficulties in aligning project-based learning with existing curriculum structures, affecting the continuity of lessons. To overcome these challenges, several strategies need to be adopted, such as redesigning flexible schedules to allow more time for project-based activities, developing practical and relevant project modules, and fostering collaboration among educators to improve teaching practices. By addressing these issues, the Merdeka Curriculum can be effectively implemented, ensuring that students in the Electrical and Mechanical Engineering departments acquire industry-relevant skills. This study aims to provide insights and recommendations for optimizing curriculum implementation

Novel, Economically Scalable Approaches for the Development of High Energy Density, Long Cycle Life, and Safe Lithium-Sulfur Batteries

Lithium-sulfur (Li-S) batteries are identified as one of the most promising next-generation battery technologies owing to their high theoretical specific energy, material abundance, and low cost advantages. However, commercialization of Li-S batteries has not been widespread due to severe technical challenges1-3 including the lithium polysulfide (PS) dissolution/shuttling effect, a major cause of fast capacity degradation over cycling in Li-S batteries. In our recent work,4 a thin film of nanolayer-polymer-coated-carbons (NPC) was deposited on sulfur electrodes (NPC-S), which enabled the resultant Li-S battery cells to deliver a high specific capacity of ~1,600 mAh/g, approaching the theoretical specific capacity limit of sulfur, without adding any appreciable dead weight or volume to the batteries. Our electrochemical, analytical, and computational results suggested that the realization of the near-theoretical specific capacity from our practical Li-S battery cells was a result of the effective PS-trapping power and the increased redox reaction kinetics for sulfur « PS’s conversions during battery charge and discharge.In this talk, we will present our continued efforts to further develop the advanced Li-S battery technology where a novel, cycle-stabilizing and safety-enhancing approach is implemented, for the first time, in the Li-S batteries, in concert with the NPC-S approach. Using this synergistic strategy, the resultant Li-S battery cells demonstrated not only the near-theoretical specific capacity of sulfur (Figure 1a), but also a significantly improved cycle stability, retaining ~80% of the initial capacity after 300 charge-discharge cycles (Figure 1b). Various characterization techniques are being employed to help understand reaction mechanisms of the outstanding Li-S battery performance. In addition to the performance benefits, we will show that these approaches are simple, economically scalable, and, therefore, offer a promising potential for the development of high energy density, long cycle life, and safe Li-S batteries for practical applications. References Wang, S.; Wang, Z.; Chen, F.; Peng, B.; Xu, J.; Li, J.; Lv, Y.; Kang, Q.; Xia, A.; Ma, L. "Electrocatalysts in lithium-sulfur batteries". Nano Research 2023, 1-30.Zhao, F. L.; Xue, J. H.; Shao, W.; Yu, H.; Huang, W.; Xiao, J. "Toward high-sulfur-content, high-performance lithium-sulfur batteries: Review of materials and technologies". J Energy Chem 2023, 80, 625-657. DOI: 10.1016/j.jechem.2023.02.009.Hu, X.; Huang, T.; Zhang, G.; Lin, S.; Chen, R.; Chung, L.-H.; He, J. "Metal-organic framework-based catalysts for lithium-sulfur batteries.". Coordination Chemistry Reviews 2023, 475, 214879.Hasan, M. W.; Huynh, K.; Lama, B.; Razzaq, A. A.; Smdani, M. G.; Akter, F. N.; Maddipudi, B.; Shende, R.; Paudel, T. R.; Xing, W. "A Highly Effective Polysulfide-Trapping Approach for the Development of High Energy Density, Scalable Lithium-Sulfur Batteries". J Electrochem Soc 2024. DOI: 10.1149/1945-7111/ad3ebf. Acknowledgment This work was supported by the Linda and Larry Pearson Endowed Chair at the Department of Mechanical Engineering, South Dakota School of Mines & Technology, and the South Dakota Governor Research Center for Electrochemical Energy Storage at South Dakota School of Mines & Technology. Figure 1

Novel application of metabolic imaging of early embryos using a light-sheet on-a-chip device: a proof-of-concept study.

Is it feasible to safely determine metabolic imaging signatures of nicotinamide adenine dinucleotide [NAD(P)H] associated auto-fluorescence in early embryos using a light-sheet on-a-chip approach? We developed an optofluidic device capable of obtaining high-resolution 3D images of the NAD(P)H autofluorescence of live mouse embryos using a light-sheet on-a-chip device as a proof-of-concept. Selecting the most suitable embryos for implantation and subsequent healthy live birth is crucial to the success rate of assisted reproduction and offspring health. Besides morphological evaluation using optical microscopy, a promising alternative is the non-invasive imaging of live embryos to establish metabolic activity performance. Indeed, in recent years, metabolic imaging has been investigated using highly advanced microscopy technologies such as fluorescence-lifetime imaging and hyperspectral microscopy. The potential safety of the system was investigated by assessing the development and viability of live embryos after embryo culture for 67 h post metabolic imaging at the two-cell embryo stage (n = 115), including a control for culture conditions and sham controls (system non-illuminated). Embryo quality of developed blastocysts was assessed by immunocytochemistry to quantify trophectoderm and inner mass cells (n = 75). Furthermore, inhibition of metabolic activity (FK866 inhibitor) during embryo culture was also assessed (n = 18). The microstructures were fabricated following a standard UV-photolithography process integrating light-sheet fluorescence microscopy into a microfluidic system, including on-chip micro-lenses to generate a light-sheet at the centre of a microchannel. Super-ovulated F1 (CBA/C57Bl6) mice were used to produce two-cell embryos and embryo culture experiments. Blastocyst formation rates and embryo quality (immunocytochemistry) were compared between the study groups. A convolutional neural network (ResNet 34) model using metabolic images was also trained. The optofluidic device was capable of obtaining high-resolution 3D images of live mouse embryos that can be linked to their metabolic activity. The system's design allowed continuous tracking of the embryo location, including high control displacement through the light-sheet and fast imaging of the embryos (<2 s), while keeping a low dose of light exposure (16 J · cm-2 and 8 J · cm-2). Optimum settings for keeping sample viability showed that a modest light dosage was capable of obtaining 30 times higher signal-noise-ratio images than images obtained with a confocal system (P < 0.00001; t-test). The results showed no significant differences between the control, illuminated and non-illuminated embryos (sham control) for embryo development as well as embryo quality at the blastocyst stage (P > 0.05; Yate's chi-squared test). Additionally, embryos with inhibited metabolic activity showed a decreased blastocyst formation rate of 22.2% compared to controls, as well as a 47% reduction in metabolic activity measured by metabolic imaging (P < 0.0001; t-test). This indicates that the optofluidic device was capable of producing metabolic images of live embryos by measuring NAD(P)H autofluorescence, allowing a novel and affordable approach. The obtained metabolic images of two-cell embryos predicted blastocyst formation with an AUC of 0.974. N/A. The study was conducted using a mouse model focused on early embryo development assessing illumination at the two-cell stage. Further safety studies are required to assess the safety and use of 405 nm light at the blastocyst stage by investigating any potential negative impact on live birth rates, offspring health, aneuploidy rates, mutational load, changes in gene expression, and/or effects on epigenome stability in newborns. This light-sheet on-a-chip approach is novel and after rigorous safety studies and a roadmap for technology development, potential future applications could be developed for ART. The overall cost-efficient fabrication of the device will facilitate scalability and integration into future devices if full-safety application is demonstrated. This work was partially supported by an Ideas Grant (no 2004126) from the National Health and Medical Research Council (NHMRC), by the Education Program in Reproduction and Development (EPRD), Department Obstetrics and Gynaecology, Monash University, and by the Department of Mechanical and Aerospace Engineering, Faculty of Engineering, Monash University. The authors E.V-O, R.N., V.J.C., A.N., and F.H. have applied for a patent on the topic of this technology (PCT/AU2023/051132). The remaining authors have nothing to disclose.

Preface

The 2nd International Symposium on Frontiers of Mechanical and Material Engineering (MME2024) is a globally recognized event to be organized by the Hubei Digital Textile Equipment Key Laboratory, China, in collaboration with the Wuhan Textile University, China, Zhongnan University, East-Siberian State University of Technology and Management, Russia, Rongzhi Sciences and Technology Center, China, was held from 21-22 September 2024 in Hangzhou, China. Since its inception in 2014, MME has successfully encompassed a wide spectrum of cuttingedge research domains, developed into a premier international event held in China and which gathered the best scientists and world class experts to share leading edge and multidisciplinary research in various fields related to mechanical engineering, materials science and modern technologies. MME serves as a prestigious international platform, this conference will continue to facilitate the dissemination of cutting-edge advancements across a spectrum of disciplines, converge students, experts, researchers, scholars, and industry professionals from different nations to share and deliberate on their latest work. This volume comprises select proceedings of 18 papers from 56 contributions submitted to MME2024. All the papers underwent a meticulous peer-review process, with each paper being evaluated by at least one expert in the relevant field. It introduces latest advancements in the subjects of mechanical engineering, materials science and advanced manufacturing technology, et al. It will be beneficial for readers from both academia and industry to understand and tackle the challenges in an efficient manner and to adopt appropriate solutions in the mentioned fields above. We would like to extend our heartfelt gratitude to invited keynote speakers: Dr. Valeriy Buryachenko, Micromechanics &amp; Composites LLC, Cincinnati, Ohio, USA; Prof. David BASSIR, French University of Technology UTBM, France; Prof. Raul Duarte Salgueiral Gomes Campilho, Department of Mechanical Engineering, ISEP - School of Engineering, Portugal, and Dr. Ghulam Yasin, Oxford Brookes University, UK, for their brilliant speeches. Thanks to all the international reviewers and program committee members for their valuable contributions and dedication. List of Conference Chair, Conference Co-Chair, Honorary Chair, Editors and Technical Program Committees are available in this Pdf.

32nd IAHR Symposium on Hydraulic Machinery and Systems

Hydropower is a reliable, versatile, and low-cost source of clean electricity generation and responsible for water management. Hydraulic machinery is an essential component of a hydropower plant to generate electricity. It is always vital to share current knowledge on research and development, including numerical analysis, design, operation, and monitoring of hydraulic machinery and systems. Research and development from academia and industry have constantly been improving the hydraulic turbine and its components design. The IAHR symposium on hydraulic machinery and systems provides unique opportunity to the academic and industrial research teams to exchange the state-of-the-art knowledge and ideas on the development of the next generation of hydropower technology. The 32nd Symposium on Hydraulic Machinery and Systems was jointly organized by the Department of Hydro and Renewable Energy and the Department of Mechanical and Industrial Engineering, Indian Institute of Technology Roorkee, India, during September 11 – 14, 2024. This preface describes the overall summary of the symposium, including the plenary &amp; technical sessions, cultural events, and technical tour. The scientific papers reviewed by the expert reviewers, accepted and presented during the symposium are published in a proceeding at IOP Science EES conference series. List of Introduction, Themes of the symposium, Highlights of the symposium, Keynote Speech, Organizing Committee, Executive Committee, Scientific Committee and Acknowledgement are available in this Pdf.