Nanoscience and Nanotechnology Commons^™

Mechanical Behavior Of Al–Al2cu–Si And Al–Al2cu Eutectic Alloys, Qian Lei, Jian Wang, Amitava Mitra

Department of Mechanical and Materials Engineering: Faculty Publications

In this study, laser rapid solidification technique was used to refine the microstructure of ternary Al–Cu–Si and binary Al–Cu eutectic alloys to nanoscales. Micropillar compression testing was performed to measure the stress–strain response of the samples with characteristic microstructure in the melt pool regions. The laser-remelted Al–Al₂Cu–Si ternary alloy was observed to reach the compressive strength of 1.59 GPa before failure at a strain of 28.5%, which is significantly better than the as-cast alloy with a maximum strength of 0.48 GPa at a failure strain of 4.8%. The laser-remelted Al–Cu binary alloy was observed to reach the compressive …

Multifunctional Polydopamine Nanomaterials For Biomedical And Environmental Applications, Hamed Gholami Derami

McKelvey School of Engineering Graduate Student Theses & Dissertations

Polydopamine (PDA), a synthetic and organic material, has emerged as a promising materialplatform for various applications in energy, environmental, and biomedical fields. PDA, formed by self-polymerization of dopamine, is rich in catechol and amine groups, which facilitate covalent conjugation and/or other non-covalent interactions with organic and inorganic materials. It is highly biocompatible, biodegradable, has broadband light absorption spectrum and excellent light-to-heat conversion efficiency. Also, it is easy to synthesize and functionalize. The combination of excellent characteristics of polydopamine-based nanomaterials, make them a promising adsorbent agent for environmental wastewater treatment and photothermal agent for biomedical applications. In the first half of …

Sensitive X-Ray And Gamma-Ray Detectors Including Perovskite Single Crystals, Jinsong Huang, Haotong Wei

Department of Mechanical and Materials Engineering: Faculty Publications

Perovskite single crystal X-ray and gamma-ray radiation detector devices include an X-ray and gamma-ray wavelength responsive active layer including a perovskite single crystal. The perovskite single crystal is a perovskite single crystal having a structure of ABX₃ , wherein A is methyl ammonium ( CH₂NH₂+), C_S+, formamidinum ( H₂NCHNH₂+) , or Rb⁺ or a mixture thereof, B is Pb²⁺ which can be partially or completely replaced by other ions including Bi³⁺, Sb³⁺, Sn²⁺ or a mixture thereof, and X is a halide …

A Molecular Dynamic Study On The Piezoelectric Properties Of Bulk Zns And Nanobelts, Rui Xie

Theses, Dissertations and Capstones

In this thesis we proved the feasibility of using classical atomic simulations, namely molecular dynamics and molecular statics, to study the piezoelectric properties of bulk and nanobelts ZnS structures, by utilizing the core-shell atomic potential model. Based on the verification of bulk and nanobelts ZnO piezoelectric constants, utilizing LAMMPS scripts and the Nyberg et al. core-shell potential, we reported the bulk ZnS piezoelectric constants calculated using three different classical interatomic core-shell ZnS potentials; the Wright and Jackson (1995) potential, the Wright and Gale (2004) potential, and the Namsani et al. (2015) potential. The simulation results showed that the Wright and …

Surface Acoustic Waves Increase Magnetic Domain Wall Velocity, Anil Adhikari, Shireen Adenwalla

Shireen Adenwalla Papers

Domain walls in magnetic thin films are being explored for memory applications and the speed at which they move has acquired increasing importance. Magnetic fields and currents have been shown to drive domain walls with speeds exceeding 500 m/s. We investigate another approach to increase domain wall velocities, using high frequency surface acoustic waves to create standing strain waves in a 3 micron wide strip of magnetic film with perpendicular anisotropy. Our measurements, at a resonant frequency of 248.8 MHz, indicate that domain wall velocities increase substantially, even at relatively low applied voltages. Our findings suggest that the strain wave …

Nickel-Iron Alloy Nanoparticle Characteristics Pre- And Post-Reaction With Orange G, Shelby L. Foster, Prashant Acharya, Mojtaba Abolhassani, Skylar Watson, Sheldon Shinn, Lauren F. Greenlee

Chemical Engineering Faculty Publications and Presentations

Bimetallic nanoparticles comprised of iron and nickel were synthesized, characterized, and evaluated to optimize the ideal metal ratio for azo dye removal from water systems. Results show that changing the molar ratio of nickel to iron caused different removal rates, as well as the extent of overall elimination of azo dye from water. Lower molar ratios, from Ni₁Fe₁₀ to Ni_2.5Fe₁₀, exhibited a higher removal efficiency of 80–99%. Higher concentrations of Ni in the catalyst, from Ni₃Fe₁₀ to Ni₅Fe₁₀ , resulted in 70–90% removal. The lower molar ratios …

Inventions Of Scientists, Engineers And Specialists From Different Countries In The Area Of Nanotechnologies. Part I, Leonid A. Ivanov, Li Da Xu, Elena Bokova, Aleksandr D. Ishkov, Svetlana Muminova

Information Technology & Decision Sciences Faculty Publications

The article provides an abstract review of patents. The results of creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials, being implemented, allow achieving a significant effect in construction, housing and community services, and related sectors of the economy. For example, the invention (A method to produce graphene-containing suspensions by means of graphite exfoliation and a device to perform it) refers to chemical and construction industries and can be used in modification of plastic lubricant, epoxy resins and concretes. The technical task of the invention is to increase efficiency of graphite exfoliation, to …

Inventions Of Scientists, Engineers And Specialists From Different Countries In The Area Of Nanotechnologies. Part Ii, Leonid A. Ivanov, Li Da Xu, Zhanna V. Pisarenko, Qiang Wang, Petr S. Prokopiev

Information Technology & Decision Sciences Faculty Publications

The article provides an abstract review of patents. The results of creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials, being implemented, allow achieving a significant effect in construction, housing and community services, and related sectors of the economy. For example, the invention «Method for liquidphase synthesis of nanostructured ceramic material in the CeO2–Sm2O3 system to create a solid oxide fuel cell» can contribute to the active development of alternative, hydrogen energy. Fuel cells have a wide range of applications – from batteries in portable electronic devices to large-scale power generation and autonomous …

Use Of Energy Consumption During Milling To Fill A Measurement Gap In Hybrid Additive Manufacturing, K. L. M. Avegnon, P. Noll, M. R. Uddin, G. Madireddy, R. Williams, A. Achuthan, M. P. Sealy

Department of Mechanical and Materials Engineering: Faculty Publications

Coupling additive manufacturing (AM) with interlayer peening introduces bulk anisotropic properties within a build across several centimeters. Current methods to map high resolution anisotropy and heterogeneity are either destructive or have a limited penetration depth using a nondestructive method. An alternative pseudo-nondestructive method to map high-resolution anisotropy and heterogeneity is through energy consumption during milling. Previous research has shown energy consumption during milling correlates with surface integrity. Since surface milling of additively manufactured parts is often required for post-processing to improve dimensional accuracy, an opportunity is available to use surface milling as an alternative method to measure mechanical properties and …

Electrostatic Flocking Of Salt-Treated Microfibers And Nanofiber Yarns For Regenerative Engineering, Alec Mccarthy, Kossi Loic M. Avegnon, Phil A. Holubeck, Demi Brown, Anik Karan, Navatha Shree Sharma, Johnson V. John, Shelbie Weihs, Jazmin Ley, Jingwei Xie

Department of Mechanical and Materials Engineering: Faculty Publications

Electrostatic flocking is a textile technology that employs a Coulombic driving force to launch short fibers from a charging source towards an adhesive-covered substrate, resulting in a dense array of aligned fibers perpendicular to the substrate. However, electrostatic flocking of insulative polymeric fibers remains a challenge due to their insufficient charge accumulation. We report a facile method to flock electrostatically insulative poly(ε-caprolactone) (PCL) microfibers (MFs) and electrospun PCL nanofiber yarns (NFYs) by incorporating NaCl during preflock processing. Both MF and NFY were evaluated for flock functionality, mechanical properties, and biological responses. To demonstrate this platform's diverse applications, standalone flocked NFY …

A Method Of Identifying Allographs In Undeciphered Scripts And Its Application To The Indus Valley Script, Shruti Daggumati, Peter Revesz

Department of Mechanical and Materials Engineering: Faculty Publications

This work describes a general method of testing for redundancies in the sign lists of ancient scripts by data mining the positions of the signs within the inscriptions. The redundant signs are allographs of the same grapheme. The method is applied to the undeciphered Indus Valley Script, which stands out from other ancient scripts by having a large proposed sign list that contains dozens of asymmetric signs that have mirrored pairs. By a statistical analysis of mirrored asymmetric signs, this paper shows that the Indus Valley Script was multi-directional and the mirroring of signs often denotes only the direction of …

Metallic Surface Doping Of Metal Halide Perovskites, Yuze Lin, Yuchuan Shao, Jun Dai, Tao Li, Yi Liu, Xuezeng Dai, Xun Xiao, Yehao Deng, Alexei Gruverman, Xiao Cheng Zeng, Jinsong Huang

Department of Mechanical and Materials Engineering: Faculty Publications

Intentional doping is the core of semiconductor technologies to tune electrical and optical properties of semiconductors for electronic devices, however, it has shown to be a grand challenge for halide perovskites. Here, we show that some metal ions, such as silver, strontium, cerium ions, which exist in the precursors of halide perovskites as impurities, can n-dope the surface of perovskites from being intrinsic to metallic. The low solubility of these ions in halide perovskite crystals excludes the metal impurities to perovskite surfaces, leaving the interior of perovskite crystals intrinsic. Computation shows these metal ions introduce many electronic states close to …

Recurrence Network Analysis Of Design-Quality Interactions In Additive Manufacturing, Ruimin Chen, Prahalada K. Rao, Yan Lu, Edward W. Reutzel, Hui Yang

Department of Mechanical and Materials Engineering: Faculty Publications

Powder bed fusion (PBF) additive manufacturing (AM) provides a great level of flexibility in the design-driven build of metal products. However, the more complex the design, the more difficult it becomes to control the quality of AM builds. The quality challenge persistently hampers the widespread application of AM technology. Advanced imaging (e.g., X-ray computed tomography scans and high-resolution optical images) has been increasingly explored to enhance the visibility of information and improve the AM quality control. Realizing the full potential of imaging data depends on the advent of information processing methodologies for the analysis of design-quality interactions. This paper presents …

Process-Structure Relationship In The Directed Energy Deposition Of Cobalt-Chromium Alloy (Stellite 21) Coatings, Ziyad M. Smoqi, Joshua Toddy, Harold (Scott) Halliday, Jeffrey E. Shield, Prahalada K. Rao

Department of Mechanical and Materials Engineering: Faculty Publications

In this work, we accomplished the crack-free directed energy deposition (DED) of a multi-layer Cobalt- Chromium alloy coating (Stellite 21) on Inconel 718 substrate. Stellite alloys are used as coating materials given their resistance to wear, corrosion, and high temperature. The main challenge in DED of Stellite coatings is the proclivity for crack formation during printing. The objective of this work is to characterize the effect of the input energy density and localized laser-based preheating on the characteristics of the deposited coating, namely, crack formation, microstructural evolution, dilution of the coating composition due to diffusion of iron and nickel from …

Inventions Of Scientists, Engineers And Specialists From Different Countries In The Area Of Nanotechnologies. Part Vi, Leonid A. Ivanov, Li D. Xu, Konstantin E. Razumeev, Zhanna V. Pisarenko, Aleksey V. Demenev

Information Technology & Decision Sciences Faculty Publications

Introduction. Advanced technologies impress people's imagination demonstrating the latest achievements (materials, methods, systems, technologies, devices etc.) that dramatically change the world. This, first of all, concerns nanotechnological inventions designed by scientists, engineers and specialists from different countries. Main part. The article provides an abstract overview of inventions of scientists, engineers and specialists from different countries: Russia, USA, China, Kazakhstan, Sweden. The results of the creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials allow, when introduced to industry, achieving a significant effect in construction, housing and communal services, and related sectors of the …

Experimental And Design Effort To Understand A Wider Sense Of Memory Application, Nicholas Zogbi

Discovery Undergraduate Interdisciplinary Research Internship

Magnetic Random-Access Memory (mRAM) is a more efficient, smaller, and less power-hungry memory device that can be implemented into computers. Using Magnetic Tunnel Junctions (MTJ) we store memory in devices that are far less complex than other types of memory with just the use of currents and magnetic fields changing the data.

In collaboration with the System-on-Chip Extension Technologies (SoCET) and Computing Advances by Probabilistic Spin Logic (CAPSL) groups, we have been working on using the characteristics of MTJs to characterize available commercial mRAM devices so we can have a better understanding of the thresholds of the MTJs. The SoCET …

Nanoplasmonic Colorimetric Sensors For Detection Of Ammonia From Water And Urine, Zuriel Caribe

Electronic Theses and Dissertations, 2020-2023

Motivated by the need for inexpensive, simple, and portable devices for aqueous chemical analysis, we developed a nanoplasmonic colorimetric sensor capable of direct detection of wide range of chemicals. This novel sensor exploits the plasmonic resonance of metallic nanostructures with natural light to transduce changes in the chemical environment to changes in color, thus offering a simple route for real-time, in-situ, and low-cost analysis of aqueous chemical species. Due to its environmental and medical relevance, we chose aqueous ammonia to analyze and determine the efficacy and limit of detection of this sensing platform. For the metallic nanostructures we selected aluminium …

Modulation Of Actin Filament Severing And Mechanics By Gelsolin In Varying Ph Conditions, Claire Toland

Electronic Theses and Dissertations, 2020-2023

Actin is an essential cytoskeletal protein that plays a critical role in cell mechanics, structure and organization with the help of actin binding proteins (ABPs). Gelsolin is a calcium-dependent ABP that severs actin filaments and caps them at their barbed end, regulating cell motility and signaling through dynamic actin cytoskeleton remodeling. A recent study has indicated that low pH stabilizes the active conformations of gelsolin. Additionally, the binding of gelsolin to the barbed end of an actin filament induces a conformational change that propagates along the actin filament. However, it has not been well understood how the complex intracellular environments …

Impact Of Crowder Size On Actin Filament Assembly Kinetics, Bryan Demosthene

Electronic Theses and Dissertations, 2020-2023

Actin is an abundant and essential cytoskeletal protein that plays a central role in eukaryotic cell structure and motility. The intracellular environment where actin assembly occurs is crowded with various organelles, proteins, and macromolecules that limit the accessible volume for biomolecular reactions. Macromolecular crowding induces excluded volume effects influencing the activity of biological molecules as well as the shape and conformation of proteins. Crowding agents, such as polysaccharides or inert polymeric molecules, are used to mimic the conditions present in intracellular spaces and provide a better understanding of interactions inside the cell. Macromolecular crowding has been shown to affect actin …

Inventions Of Scientists, Engineers And Specialists From Different Countries In The Area Of Nanotechnologies. Part Iii, L. A. Ivanov, L. D. Xu, E. S. Bokova, A. V. Demenev, V. A. Ivanov

Information Technology & Decision Sciences Faculty Publications

Introduction. Advanced technologies impress people’s imagination demonstrating the latest achievements (materials, methods, systems, technologies, devices etc.) that dramatically change the world. This, first of all, concerns nanotechnological inventions designed by scientists, engineers and specialists from different countries.

Main part. The article provides an abstract review of patents. The results of creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials, being implemented, allow achieving a significant effect in construction, housing and community services, and related sectors of the economy. For example, the invention «Composite material with oriented carbon nanotubes» refers to the area of …

Inventions Of Scientists, Engineers And Specialists From Different Countries In The Area Of Nanotechnologies. Part Iv, Leonid A. Ivanov, Li Da Xu, Zhanna V. Pisarenko, Cahn T. Nguyen, Svetlana R. Muminova

Information Technology & Decision Sciences Faculty Publications

Introduction. Advanced technologies impress people's imagination demonstrating the latest achievements (materials, methods, systems, technologies, devices etc.) that dramatically change the world. This, first of all, concerns nanotechnological inventions designed by scientists, engineers and specialists from different countries. Main part. The paper briefly reviews inventions made by scientists, engineers and specialists from different countries: Russia, USA, China, Belarus, Great Britain, Vietnam, Denmark, the Kyrgyz Republic. The application of the results of scientists', engineers' and specialists' investigations, including inventions in the area of nanotechnology and nanomaterials allow achieving significant efficiency in construction, house and communal service, related sectors of economy. For example, …

Discharge Mode Transition In He/Ar Atmospheric Pressure Plasma Jet And Its Inactivation Effect Against Tumor Cells In Vitro, Bolun Pang, Zhijie Liu, Sitao Wang, Yuting Gao, Huaiyan Zhang, Feng Zhang, Xiamin Tantai, Dehui Xu, Dingxin Liu, Michael G. Kong

Bioelectrics Publications

Discharge characteristic comparisons between He and Ar plasma jets have been extensively reported, but is rarely reported for the comprehensive study of discharge mode transition from He jet to Ar jet, especially its induced liquid chemistry and biological effect. In this paper, we investigate the plasma jet mode transformation by varying the Ar contents in the He/Ar mixing working gas, particularly focusing on the effect of liquid chemistry of plasma activated water (PAW) and the corresponding inactivation effect against tumor cells in vitro. The mode transition process from He jet to Ar jet is characterized by the discharge images, …

Perceived Importance Of Aac Messages To Support Communication In Rehabilitation Settings, Susan Koch Fager, Judith M. Burnfield, Chase M Pfeifer, Tabatha Sorenson

Department of Mechanical and Materials Engineering: Faculty Publications

Purpose: Permanent or temporary speech loss can occur due to a variety of medical conditions and often requires individuals to use augmentative and alternative communication (AAC) strategies and technologies to support communication. The use of AAC in medical and rehabilitation settings is critical to ensure the health, safety and psychological well-being of communicatively vulnerable individuals.

Method: This study surveyed the perceived importance of communication messages within five categories (Basic Needs, Patient-Provider Specific Communication, Social, Feelings, and Messages for Young Children) by individuals with disability who have undergone recent medical care as well as by rehabilitation care providers.

Results: Results indicated …

Feasibility Of Motor-Assisted Elliptical To Improve Walking, Fitness And Balance Following Pediatric Acquired Brain Injury: A Case Series, Judith M. Burnfield, Guilherme Manna Cesar, Thad W. Buster

Department of Mechanical and Materials Engineering: Faculty Publications

Purpose: Walking, fitness, and balance deficits are common following acquired brain injury (ABI). This study assessed feasibility, acceptability, and usefulness of a modified motor-assisted elliptical (ICARE) in addressing walking, fitness, and balance deficits in children with chronic ABIs.

Methods: Three children (> 5 years post-ABI) completed 24 ICARE exercise sessions (exercise time, speed, and time overriding motor-assistance gradually increased) to promote mass repetition of gait-like movements and challenge cardiorespiratory fitness. Parents’ and children’s perceptions of ICARE’s safety, comfort, workout, and usability were assessed. Cardiovascular response, gait and balance outcomes were assessed.

Results: No adverse events occurred. Parent’s …

A Novel Large Animal Model Of Smoke Inhalation-Induced Acute Respiratory Distress Syndrome, Premila D. Leiphrakpam, Hannah R. Weber, Andrea Mccain, Roser Romaguera Matas, Ernesto Martinez Duarte, Keely L. Buesing

Department of Mechanical and Materials Engineering: Faculty Publications

Background: Acute respiratory distress syndrome (ARDS) is multifactorial and can result from sepsis, trauma, or pneumonia, amongst other primary pathologies. It is one of the major causes of death in critically ill patients with a reported mortality rate up to 45%. The present study focuses on the development of a large animal model of smoke inhalation-induced ARDS in an effort to provide the scientific community with a reliable, reproducible large animal model of isolated toxic inhalation injury-induced ARDS. Methods: Animals (n=21) were exposed to smoke under general anesthesia for 1 to 2 h (median smoke exposure=0.5 to 1 L of …

Ultrasound-Activated Ciliary Bands For Microrobotic Systems Inspired By Starfish, Cornel Dillinger, Nitesh Nama, Daniel Ahmed

Department of Mechanical and Materials Engineering: Faculty Publications

Cilia are short, hair-like appendages ubiquitous in various biological systems, which have evolved to manipulate and gather food in liquids at regimes where viscosity dominates inertia. Inspired by these natural systems, synthetic cilia have been developed and utilized in microfluidics and microrobotics to achieve functionalities such as propulsion, liquid pumping and mixing, and particle manipulation. Here, we demonstrate ultrasound-activated synthetic ciliary bands that mimic the natural arrangements of ciliary bands on the surface of starfish larva. Our system leverages nonlinear acoustics at microscales to drive bulk fluid motion via acoustically actuated small-amplitude oscillations of synthetic cilia. By arranging the planar …

Preperitoneal Insufflation Pressure Of The Abdominal Wall In A Porcine Model, Riley E. Reynolds, Benjamin Wankum, Sean J. Crimmins, Mark A. Carlson, Benjamin S. Terry

Department of Mechanical and Materials Engineering: Faculty Publications

Background Most complications and adverse events during laparoscopic surgery occur during initial entry into the peritoneal cavity. Among them, preperitoneal insufflation occurs when the insufflation needle is incorrectly placed, and the abdominal wall is insufflated. The objective of this study was to find a range for static pressure which is low enough to allow placement of a Veress needle into the peritoneal space without causing preperitoneal insufflation, yet high enough to separate abdominal viscera from the parietal peritoneum.

Methods A pressure test was performed on twelve fresh porcine carcasses to determine the minimum preperitoneal insufflation pressure and the minimum initial …

Development Of Chemical Methods For Oligonucleotide Purification, Paramagnetic Labeling And Synthesis Of Dna-Based Advanced Materials, Muhan He

Legacy Theses & Dissertations (2009 - 2024)

This thesis describes a chemical method for alternative oligonucleotide purification that is non-chromatographic and gel-free and allows to routinely synthesize and purify long functional RNA strands. The purification of long RNAs is based on the bio-orthogonal inverse electron demand Diels-Alder (IEDDA) chemistry between trans-cyclooctene (TCO) and tetrazine (Tz). Target oligonucleotide strands are selectively tagged with Tz and can be captured and purified from the failure sequences with immobilized TCO. RNA strands are synthesized on solid support through a photolabile linker to avoid the loss of Tz tag. Purity of the isolated oligonucleotides was evaluated using gel electrophoresis, HPLC and mass …

Surface Enhanced Raman Spectroscopy Analysis Of Thin-Smear-Contamination On Hdd Read-Write Head, Charin Seesomdee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Surface-enhanced Raman spectroscopy (SERS) is one of the most powerful analytical techniques for the identification of molecules in microelectronics industry for failure analysis protocol. In this work, a dry-processed gold nanoclusters were prepared by magnetron sputtering deposition to promote the enhancement of the Raman signal for the best intensity gain from selected common polymers found in hard disk drive as surface contamination. The optimized sputtering conditions was applied for SERS on polycarbonate (PC), polyethylene terephthalate (PET), polypropylene (PP), and high-density polyethylene (HDPE). The Raman spectrum showed the average Raman signal intensity gain at about 114%, 78%, 254%, and 226% respectively. …

Multi-Level Analysis Of Atomic Layer Deposition Barrier Coatings On Additively Manufactured Plastics For High Vacuum Applications, Nupur Bihari

Dissertations, Master's Theses and Master's Reports

While hardware innovations in micro/nano electronics and photonics are heavily patented, the rise of the open-source movement has significantly shifted focus to the importance of obtaining low-cost, functional and easily modifiable research equipment. This thesis provides a foundation of open source development of equipment to aid in the micro/nano electronics and photonics fields.

First, the massive acceptance of the open source Arduino microcontroller has aided in the development of control systems with a wide variety of uses. Here it is used for the development of an open-source dual axis gimbal system. This system is used to characterize optoelectronic properties of …