Materials Science and Engineering Commons^™

High-Performance No2 Gas Sensor Based On Reduced Graphene Oxide/Zro2 Hybrids, Ali Jabbar Fraih, N. Naeema, Fatima Fadhil Abbas

Journal of Metals, Materials and Minerals

The increasing concern over environmental pollution, particularly from nitrogen dioxide (NO2) emissions, necessitates the development of efficient NO2 detection sensors. This study introduces reduced graphene oxide (rGO)/ZrO2 hybrids for enhanced NO2 gas sensing. Utilizing a modified Hummer’s method, graphene oxide (GO) flakes were synthesized and subsequently sputtered with 10 nm ZrO2 film, followed by thermal annealing to produce rGO/ZrO2 hybrids. The hybrids were characterized using various techniques including SEM, TEM, AFM, Raman spectroscopy, and XRD, confirming successful synthesis and reduction of GO, as well as the formation of ZrO2 nanoparticles. Gas sensing tests revealed superior sensitivity to NO2 in the …

Phase Separation Promotes Fcc-Phase Mechanical Twinning In Alcocrfemo0.05ni2 High Entropy Alloy, Zifeng Zhang, Liang Chu, Jiqing Zhao, Bing Xu, Qilu Ye

Journal of Metals, Materials and Minerals

The AlCoCrFeMo0.05Ni2 high entropy alloy (HEA) can remarkably enhance its ductility through high-temperature annealing. Nevertheless, the underlying mechanism remains under explored. Herein, we utilized molecular dynamics simulations (MD) to calculate the generalized stacking fault energy (GSFE) curves and uniaxial tensile behavior. Notably, the twin inclination of the FCC phase increases significantly after annealing. During plastic deformation, the FCC phase in the annealed alloy exhibits a substantially higher formation of twinning and stacking faults compared to the as-cast alloy. This increased twin inclination after annealing is the fundamental mechanism contributing to the enhancement of high-temperature ductility.

Recent Advances In Synthesis And Bio-Applications Of Natural Stabilizers For Metal Nanoparticles, Abhishek Sharma, Navneet Kaur, Ayashkanta Nanda, Manvinder Kaur, Rajeev Sharma, Harvinder Singh Sohal

Journal of Metals, Materials and Minerals

Due to their exceptional physicochemical properties, the synthesis and application of metal nano-particles gained significant traction and a grip in industries and scientific fields or regions. However, the thermodynamic instability of metal nanoparticles poses or leads to challenges in their controlled synthesis and stabilization. To address this stability and the immobilization strategies, natural polymers such as cellulose, starch, alginate, chitosan, and hyaluronic acid have been explored for their non-toxic, biodegradable, and environmentally friendly characteristics. Recent advances in nanotechnology have led to an increased focus on these natural polymer’s utilization as effective stabilizers for diverse metal nanoparticles. This review comprehensively examines …

Influence Of Bi Substitution On Structural And Optical Properties Of Lafeo3 Perovskite, Mohammed Sadok Mahboub, Ouarda Ben Ali, Soria Zeroual, Ghani Rihia, Mourad Mimouni, Imad Hamadneh, Samir Bayou, Hani Boulahbel, Adel Benarfa, Ferhat Rehouma

Journal of Metals, Materials and Minerals

The sol-gel self-ignition method has successfully synthesized a series of homogenous perovskites La1-xBixFeO3 (x=0.0, 0.2, 0.4, 0.6, and 0.8) nanoparticles. Rietveld refinement results from XRD patterns revealed no secondary phases in pure and Bi-substituted LaFeO3 samples. The structural transition from orthorhombic at x = 0.0 until x=0.6 (space group Pbnm) to rhombohedral at x=0.8 (space group R3c) was observed. Lattice parameter values increase slightly with Bi concentration due to the substitution of Bi in the LaFeO3 structure. The average crystallite size D was found to vary between 19 nm and 50 nm. The combination of XRD and SEM demonstrated that …

Nanostructure Of Tio2 And Wo3 Multilayer Films Deposited On Ito Glass For Electrochromic Enhanced Photocatalytic Activity, Atsakorn Chuenkruit, Watcharaporn Thongjoon, Kamon Aiempanakit, Montri Aiempanakit, Chantana Aiempanakit

Journal of Metals, Materials and Minerals

The photocatalytic activity (PA) by electrochromic (EC) enhancement of single and multilayer films of TiO2, WO3, TiO2/WO3, and WO3/TiO2 was investigated. All films were deposited from metal on an ITO glass substrate using direct current (DC) magnetron sputtering via an oblique angle deposition (OAD) technique at 85°. Subsequently, a thermal oxidation (TO) process at 500℃ was applied for the samples to form metal oxide films. The morphology, elemental composition, crystal structure, and optical properties were studied by using field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffractometry (XRD), and UV-vis spectroscopy, respectively. The photocatalytic properties were investigated …

Surface Characteristics Evolution Of 316l Stainless Steel Induced By Tension Loading, Kanokwan Antanam, Surasak Kuimalee, Panya Buahombura, Waraporn Piyawit

Journal of Metals, Materials and Minerals

316L stainless steel has been employed as a medical implant material owing to its advantageous biocompatibility and durability. The microstructure and surface characteristics of 316L play a crucial role in implant application. Diverse processing methods were utilized to modify the surface properties of 316L to customize the characteristics of medical devices. Mechanical deformation induces changes in the microstructure and causes changes in surface topography. In this study, we introduced deformation to 316L by applying uniaxial tension at strain values ranging from 2% to 25%. During sample preparation, electrochemical polishing was employed to eliminate the deformed layers generated by mechanical grinding. …

Sbr Elastomer Response To Renewable Diesel Blends: An Experimental Investigation, Andrias Rahman Wimada, Ni Putu Dian Nitamiwati, Fatimah Tresna Pratiwi, Maharanni Dewi Solikhah, Bina Restituta Barus, Eki Dwi Wijanarko, Riesta Anggarani, Lies Asiyah, Setyo Widodo, Arfi Thahar, Soni Solistia Wirawan

Journal of Metals, Materials and Minerals

To investigate the impact of Styrene Butadiene Rubber (SBR) exposure to renewable fuels during handling and storage processes, compatibility tests were conducted on three different renewable fuel mixtures: 30% biodiesel, 40% biodiesel, and 30% biodiesel + 10% hydrogenated vegetable oil. These tests involved static immersion experiments conducted at room temperature for a duration of 1000 h, following the ASTM D471 standards. Before and after the immersion tests, the physical properties and visually assessed elastomers concentrations were investigated by varying the SBR content. Additionally, the post-immersion fuel properties were examined. The results showed that mass and volume swelling increased with the …

Bifunctional Cationic Modification Of Modal Fabric For Sustainable In Textile Dyeing With Spent Coffee Grounds, Monthon Nakpathom, Rattanaphol Mongkholrattanasit, Sarute Ummartyotin, Pisutsaran Chitichotpanya, Nattaya Vuthiganond

Journal of Metals, Materials and Minerals

In order to dye cellulose or regenerated cellulose with natural dyes, toxic metal mordants are generally employed. In response to this issue, the novel bifunctional cationic agent was pretreated to modify modal (regenerated cellulose) fabric prior to dyeing to enhance the fiber-dye affinity. The cationization reaction was carried out using a compound containing bicationic sites, N,N'-(oxybis (ethane-2,1-diyl))bis(3-chloro-2-hydroxy-N,N-dimethylpropan-1-aminium. This unique cationic agent is capable of producing nonvolatile amine and has no odor problem. The successful cationic modification was confirmed through FTIR spectroscopy and zeta potential measurement. The cationized process was optimized at a cationic and sodium hydroxide concentration …

Designing Biphasic Nanocellulose Hydrogels To Mimic The Complex Cartilage-Bone Interface, Sairash Sairash, Sirinee Jirajessada, Supansa Yodmuang

Journal of Metals, Materials and Minerals

Osteochondral lesions, which affect both the cartilage and the bone, present significant challenges in treatment due to the complex mechanical and biochemical properties of these tissues. A crucial consideration in developing tissue replacements for these lesions is the simultaneous regeneration of cartilage and calcified cartilage, which forms the transition zone to bone. Our current study aims to fabricate a bilayer polymeric hydrogel designed not only to support cartilage regeneration but also to serve as an interface between cartilage and bone. The bilayer hydrogel was created by combining oxidized bacterial nanocellulose, gelatin, and alginate in one layer, while the other layer …

The Impact Of Hot Rolling, Zn And Sn On The Mechanical And Corrosion Characteristics Of Mg-Zn-Ca Alloys, Halil Eren, Ali Güngör, Erkan Koç, Harun Çuğ

Journal of Metals, Materials and Minerals

In this study, it was aimed to develop a biodegradable metallic plate that is an alternative to bioinert metal plates. The main advantage of using biodegradable materials for implants is that they can be gradually replaced with the patient's own tissue, which reduces the need for additional surgeries to remove the implant after it has served its purpose. Magnesium and its alloys can provide biocompatibility as orthopedic implant materials. Mg-Zn-Ca and Mg-Zn-Ca-Sn alloys were prepared using the gravity die casting method. Zn (1.0 wt% and 2.0 wt%) and Sn (0.0 wt%, 0.5 wt% and 1.0 wt%) ratios were used as …

Nutrient Retention And Availability Of Biochars Prepared By Co-Pyrolysis Of Vinasse With Sugarcane Filter Cake, Siraprapra Suwanree, Jesper T.N. Knijnenburg, Emirhan M. Ölҫer, Kaewta Jetsrisuparb

Journal of Metals, Materials and Minerals

The disposal of vinasse, a nutrient-rich by-product of ethanol production, is challenging because of the low pH and emissions of harmful gases and smells. Here, biochars were produced by pyrolysis of mixtures of filter cake and vinasse (0.25 w/v to 1 w/v) at 550℃. The effects of filter cake to vinasse ratios on the biochar yield, pH, ash content, total nutrient (P, K, Ca, and Mg) content, and nutrient availability were investigated. Increasing the filter cake to vinasse ratio increased the biochar yield and ash content and lowered the biochar pH from 10.3 for 0.25-BC to 8.2 for filter cake …

Design And Performance Of Superconducting Switches For Nanowire Detectors In Magnetic Fields, Timothy James Draher

Graduate Research Theses & Dissertations

Superconducting nanowire devices fit a broad spectrum of applications, including particle detection and quantum computing, and their expanding use across various fields highlights their role in the hybridization of superconducting and conventional semiconductor electronics. Despite their potential, the low signal output of these devices raises challenges in scalability and integration, particularly in applications for nuclear and high-energy physics, where resilience in magnetic fields is becoming a critical optimization factor. The superconducting nanowire cryotron (nTron) addresses these issues by providing operational gain and logic switching in superconducting nanowire circuits, demonstrating adaptability to multiple materials. This dissertation focuses on modifying the conventional …

Optimizing Metal 3d Printing, Abram Brown, Lauren Novak

Williams Honors College, Honors Research Projects

Partnered with Lauren Novak we are doing our senior design project on optimizing metal 3D printing with the company nVent. A brief scope of the project is that nVent uses a metal 3D printer to create tooling that is used in a hydraulic pressed and used to create iterations of prototypes during the design process. We will be researching how to decrease the amount the time of the 3D print while doing load tests with v­blocks, wiping tools, and a rib tool. The tests will be on the tooling made using different parameters including infill density, infill geometry, wall thickness, …

Extending Trailer, Alex Grove

Williams Honors College, Honors Research Projects

The goal of this research project is to revolutionize the convenience in towable transportation. This innovative design aims to enhance the versatility of pull-behind trailers by incorporating an extendable feature, allowing users to effortlessly adjust the length according to their specific needs. Whether navigating tight spaces or accommodating extra cargo, our trailer adapts to diverse situations, providing unmatched flexibility. In addition to its adjustable length, the trailer is engineered to be compactable, addressing the storage constraints often faced by users with limited space. The collapsible design ensures easy storage without compromising on functionality, making it an ideal solution for individuals …

Gan Hemt And Air Core Magnetics Based Power Converters Evaluations At Cryogenic Temperature, Yuqi Wei, Md Maksudul Hossain, H. Alan Mantooth

Electrical Engineering Faculty Publications and Presentations

Cryogenic power electronics is both advantageous and indispensable in many applications, like deep space probe, military electric vehicle, magnetic resonance imaging etc. Among different semiconductors, the gallium nitride (GaN) high electron mobility transistor (HEMT) is the most promising candidate for cryogenic applications with significant conduction loss and switching loss reductions. Moreover, there is no carrier freeze out effect for the GaN HEMTs, which is applicable in extreme low temperature operating conditions. In this work, the efficiency of GaN HEMTs based power converters with different power levels (from several Watts to several kiloWatts) are evaluated at cryogenic temperature. Three different commercial …

The Impact Of Modern Buildings On Traditional Urban Environments And Urban Identity, Ann S. Ibrahim

Al-Esraa University College Journal for Engineering Sciences

Contemporary cities face significant challenges in integrating modern buildings into traditional urban environments while preserving urban identity. This study focuses on the relationship between modern architecture and urban heritage. The research problem revolves around how modern buildings affect urban identity in traditional areas, and whether they can interact positively with the urban context without distorting its traditional character.

The study aims to analyze this impact by examining a range of global examples using architectural indicators such as visual integration, spatial integration, material harmony, urban scale, accessibility, and environmental impact. A three-point scale (weak, partial, excellent) was applied to assess each …

Photoluminescence Of Beryllium-Related Defects In Gallium Nitride, Mykhailo Vorobiov, Mykhailo Vorobiov

Theses and Dissertations

This study explores the potential of beryllium (Be) as an alternative dopant to magnesium (Mg) for achieving higher hole concentrations in gallium nitride (GaN). Despite Mg prominence as an acceptor in optoelectronic and high-power devices, its deep acceptor level at 0.22 eV above the valence band limits its effectiveness. By examining Be, this research aims to pave the way to overcoming these limitations and extend the findings to aluminum nitride and aluminum gallium nitride (AlGaN) alloy. Key contributions of this work include. i)Identification of three Be-related luminescence bands in GaN through photoluminescence spectroscopy, improving the understanding needed for further material …

Nickel Superalloy Composition And Process Optimization For Weldability, Cost, And Strength, Sophie A. Mehl

Dissertations, Master's Theses and Master's Reports

To advance sustainability efforts, electric power plants have reduced specific carbon dioxide emissions by increasing operating temperatures and pressures to improve power generation efficiency. The latest improvements are utilized in advanced ultra-supercritical power generation. To meet these operating conditions, nickel superalloys are used in the highest temperature components; however, they are expensive and present weldability challenges. This project aims to experimentally optimize a nickel superalloy to improve material weldability and decrease cost without compromising strength. Three optimized compositions were developed, and their microstructures and mechanical properties were compared to Nimonic 263, a common nickel superalloy in electric power plants. The …

Anaerobic Reductive Bioleaching Of Manganese Ores, Neha Sharma

Dissertations, Master's Theses and Master's Reports

Manganese extraction by biological methods is a green and economical way to produce manganese from low as well as high grade manganese ores. This is especially important for US ores, which are primarily either small in extent, low-grade with a high iron content, or both. They are therefore not suitable for conventional mining, which is very capital-intensive and requires a large up-front investment and are therefore imported at high costs. The goal is therefore to develop a process that can be applied at small scales, with minimal startup costs, and low equipment and labor requirements. It is also critical to …

Far-Field Passive Wireless Sensors Composed Of Electroceramic Materials For Harsh Environment Applications, Kevin M. Tennant

Graduate Theses, Dissertations, and Problem Reports (ETD)

The demand for high temperature sensing technologies in industrial applications has been steadily increasing, driven by the need for precise monitoring and control in extreme environments. This thesis presents an investigation into the development and optimization of passive wireless sensors for high temperature sensing applications. The research focuses on overcoming the challenges associated with traditional sensing methods by leveraging passive wireless sensor technology, offering advantages such as reduced complexity, improved reliability, and enhanced flexibility.

A passive wireless high temperature sensor for far-field applications was developed for stable temperature sensing up to 1000 °C. The goal is to leverage the properties …