Nanoscience and Nanotechnology Commons^™

Design Of An Innovative Hybrid Sandwich Protective Device For Offshore Structures, Hozhabr Mozafari, Fabio Distefano, Gabriella Epasto, Linxia Gu, Emanoil Linul, Vincenzo Crupi

Department of Mechanical and Materials Engineering: Faculty Publications

Lightweight foam sandwich structures have excellent energy absorption capacity, combined with good mechanical properties and low density. The main goal of this study is to test the application of an innovative hybrid sandwich protective device in an offshore wind turbine (OWT). The results are useful for offshore structure applications. Different lightweight materials (aluminum foam, agglomerated cork, and polyurethane foam) were investigated using experimental tests and numerical simulations. Closed-cell aluminum foam showed the best performance in terms of the energy absorption capacity during an impact. As such, a Metallic Foam Shell (MFS) device was proposed for the fender of offshore wind …

A Brief Review Of The Impact Of Silver Nanoparticles On Agriculture And Certain Biological Properties: A Case Study, Sushmashree Krishnappa, Shankramma Kalikeri, Raj Kumar H. Garampalli, Lingaraju H G, Charan Kumar Kachintaya

International Journal of Health and Allied Sciences

Nanotechnology is progressively becoming a popular field of research because it has been successful in changing our agricultural and food systems. According to research published by the UNFAO, agriculture as well as its derivatives would be in high demand sooner or later, owing to nutritional changes. Nanoparticles have been reported to be used in an agricultural sector, because of its capacity to encourage crop growth and yield. Among metal nanoparticles, Silver Nanoparticles (AgNPs) are attracting a lot of attention. We have highlighted some of the agricultural uses of AgNPs, which include pest management, plant disease detection, crop enhancement, and crop …

Spatially Guided Construction Of Multilayered Epidermal Models Recapturing Structural Hierarchy And Cell–Cell Junctions, Haiwei Zhai, Xiaowei Jin, Grayson Minnick, Jordan Rosenbohm, Mohammed Abdul Haleem Hafiz, Ruiguo Yang, Fanben Meng

Department of Mechanical and Materials Engineering: Faculty Publications

A current challenge in 3D bioprinting of skin equivalents is to recreate the distinct basal and suprabasal layers and promote their direct interactions. Such a structural arrangement is essential to establish 3D stratified epidermis disease models, such as for the autoimmune skin disease pemphigus vulgaris (PV), which targets the cell– cell junctions at the interface of the basal and suprabasal layers. Inspired by epithelial regeneration in wound healing, a method that combines 3D bioprinting and spatially guided self-reorganization of keratinocytes is developed to recapture the fine structural hierarchy that lies in the deep layers of the epidermis.Herein, keratinocyteladen fibrin hydrogels …

Influence Of Nano-Sized Sic On The Laser Powder Bed Fusion Of Molybdenum, Nathan E. Ellsworth, Ryan A. Kemnitz, Cayla C. Eckley, Brianna M. Sexton, Cynthia T. Bowers, Joshua R. Machacek, Larry W. Burggraf

Faculty Publications

Consolidation of pure molybdenum through laser powder bed fusion and other additive manufacturing techniques is complicated by a high melting temperature, thermal conductivity and ductile-to-brittle transition temperature. Nano-sized SiC particles (0.1 wt%) were homogeneously mixed with molybdenum powder and the printing characteristics, chemical composition, microstructure, mechanical properties were compared to pure molybdenum for scan speeds of 100, 200, 400, and 800 mm/s. The addition of SiC improved the optically determined density and flexural strength at 400 mm/s by 92% and 80%, respectively. The oxygen content was reduced by an average of 52% over the four scan speeds analyzed. Two mechanisms …

Enabling Nanoimprint Lithography Techniques Across Multiple Manufacturing Processes, Vincent Einck

Doctoral Dissertations

Advanced nanooptics in the areas of flat lenses, diffractive elements, and tunable emissivity require a route to high throughput manufacturing. Nanooptics are often demanding of high refractive index materials, nanometer precision and ease of fabrication. Nanoimprint lithography (NIL) is a low-cost, high throughput manufacturing technique beginning to be realized in commercial industry.^1,2 The NIL process is an ideal manufacturing candidate due to its ability to have a fast process time, efficient use of materials, repeatability and high precision while also having wide diversity of potential structures and material choices. Appling NIL techniques to other facets of manufacturing enable the …

Modeling Of Two-Dimensional And Biological Materials Towards Diverse Nano-Systems Applications, Jatin Kashyap

Dissertations

This dissertation studies the demonstration of materials ranging from two-dimensional (2D) materials to small bio-molecules using various atomistic/molecular and sub-atomic particles (electron, hole, excitons) modeling techniques for multi-domain applications. Three categories of materials/systems are investigated as follows: 2D materials, biological materials, and complexes of 2D and biological materials.

The first problem demonstrates wrinkles' ubiquitous presence in two-dimensional materials significantly alters their properties. It is observed that water molecules, sourced from ambient humidity or transfer method, can get diffused in between Graphene and the substrate during the Graphene growth. The water diffusion causes/assists wrinkle formation in Graphene, which influences its properties. …

Biofilms: Formation, Research Models, Potential Targets, And Methods For Prevention And Treatment, Yajuan Su, Jaime T. Yrastorza, Mitchell Matis, Jenna Cusick, Siwei Zhao, Guangshun Wang, Jingwei Xie

Department of Mechanical and Materials Engineering: Faculty Publications

Due to the continuous rise in biofilm-related infections, biofilms seriously threaten human health. The formation of biofilms makes conventional antibiotics ineffective and dampens immune clearance. Therefore, it is important to understand the mechanisms of biofilm formation and develop novel strategies to treat biofilms more effectively. This review article begins with an introduction to biofilm formation in various clinical scenarios and their corresponding therapy. Established biofilm models used in research are then summarized. The potential targets which may assist in the development of new strategies for combating biofilms are further discussed. The novel technologies developed recently for the prevention and treatment …

Biobased Packaging Materials From Cellulose Nanofibrils Produced From Virgin Wood Pulp Or Recycled Cardboard Pulp, Md Ikramul Hasan

Electronic Theses and Dissertations

Self-standing cellulose nanofibril (CNF) films are regarded as one of the promising alternatives to current petroleum-based packaging materials. The mechanical and barrier properties of CNF films are not yet up to the mark for certain applications, especially at high relative humidity. Those properties of CNF films can be tuned by the drying methods of films, degree of fibrillation, cross-linking, and controlled shrinkage. A comprehensive understanding of these processes and their influence on the structure and properties of CNF films have been presented in this thesis.

First, we prepared CNF films from CNF suspensions with two different degrees of fibrillation- standard …

Comparative Study Of Tapered Versus Conventional Cylindrical Balloon For Stent Implantation In Stenotic Tapered Artery, Xiang Shen, Jiabao Jiang, Hongfei Zhu, Kaikai Lu, Pengfei Dong, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

The natural tapering of coronary arteries often creates a dilemma for optimal balloon sizing during stenting. The influence of different balloon types, namely, a tapered balloon and a conventional cylindrical balloon, on the mechanical performance of the stent as well as arterial mechanics was investigated via the finite element method. Stent free-expansion and stent deployment in a stenotic tapered artery were investigated numerically. The biomechanical behavior of the two balloon types was compared in terms of stent foreshortening, stent deformation, stent stress distribution, and arterial wall stress distribution. Results indicate that balloon types affect the transient behavior of the stent …

Three-Dimensional Printed Abdominal Imaging Windows For In Vivo Imaging Of Deep-Lying Tissues, Mitchell Kuss, Ayrianne J. Crawford, Olawale A. Alimi, Michael A. Hollingsworth, Bin Duan

Department of Mechanical and Materials Engineering: Faculty Publications

The ability to microscopically image diseased or damaged tissue throughout a longitudinal study in living mice would provide more insight into disease progression than having just a couple of time points to study. In vivo disease development and monitoring provides more insight than in vitro studies as well. In this study, we developed permanent 3D-printed, surgically implantable abdominal imaging windows (AIWs) to allow for longitudinal imaging of deep-lying tissues or organs in the abdominal cavity of living mice. They are designed to prevent organ movement while allowing the animal to behave normally throughout longitudinal studies. The AIW also acts as …

Synthesis And Consolidation Of Metal Oxide Nanocrystals Via Nonthermal Plasma, Austin Cendejas

McKelvey School of Engineering Theses & Dissertations

Nonthermal plasmas offer a unique nonequilibrium environment that has been leveraged in a wide variety of applications in the fields of material processing, lighting, and waste management to name a few. In all of these cases, the plasma serves as a source of high energy electrons, ions, reactive gas species, and radicals that interact in several ways with surfaces brought into contact with the plasma. Specifically, nonthermal plasmas have been shown to be very successful in achieving continuous, high-throughput, monodisperse nanocrystals of a wide variety of materials. The crystallinity of nanoparticles synthesized in nonthermal plasmas can be attributed to the …

Testing Oxygenated Microbubbles Via Intraperitoneal And Intrathoracic Routes On A Large Pig Model Of Lps-Induced Acute Respiratory Distress Syndrome, Riaz Ur Rehman Mohammed, Nathaniel T. Zollinger, Andrea R. Mccain, Roser Romaguera-Matas, Seth P. Harris, Keely L. Buesing, Mark A. Borden, Benjamin S. Terry

Department of Mechanical and Materials Engineering: Faculty Publications

With a mortality rate of 46% before the onset of COVID-19, acute respiratory distress syndrome (ARDS) affected 200,000 people in the US, causing 75,000 deaths. Mortality rates in COVID-19 ARDS patients are currently at 39%. Extrapulmonary support for ARDS aims to supplement mechanical ventilation by providing life-sustaining oxygen to the patient. A new rapid-onset, human-sized pig ARDS model in a porcine intensive care unit (ICU) was developed. The pigs were nebulized intratracheally with a high dose (4 mg/kg) of the endotoxin lipopolysaccharide (LPS) over a 2 h duration to induce rapid-onset moderate-to- severe ARDS. They were then catheterized to monitor …

Vibrating Flexoelectric Micro-Beams As Angular Rate Sensors, Yilin Qu, Feng Jin, Jiashi S. Yang

Department of Mechanical and Materials Engineering: Faculty Publications

We studied flexoelectrically excited/detected bending vibrations in perpendicular directions of a micro-beam spinning about its axis. A set of one-dimensional equations was derived and used in a theoretical analysis. It is shown that the Coriolis effect associated with the spin produces an electrical output proportional to the angular rate of the spin when it is small. Thus, the beam can be used as a gyroscope for angular rate sensing. Compared to conventional piezoelectric beam gyroscopes, the flexoelectric beam proposed and analyzed has a simpler structure.

Vibrating Flexoelectric Micro-Beams As Angular Rate Sensors, Yilin Qu, Feng Jin, Jiashi S. Yang

Department of Mechanical and Materials Engineering: Faculty Publications

We studied flexoelectrically excited/detected bending vibrations in perpendicular directions of a micro-beam spinning about its axis. A set of one-dimensional equations was derived and used in a theoretical analysis. It is shown that the Coriolis effect associated with the spin produces an electrical output proportional to the angular rate of the spin when it is small. Thus, the beam can be used as a gyroscope for angular rate sensing. Compared to conventional piezoelectric beam gyroscopes, the flexoelectric beam proposed and analyzed has a simpler structure.

Variations In Copper Form Exposure Differentially Modulate Zea Mays (Corn) Physiological Responses, Carolina Valdes Bracamontes

Open Access Theses & Dissertations

In the present study, Zea mays seedlings grown under nano Cu(OH)2 (nCu), bulk Cu(OH)2 (bCu), and ionic CuSO4 (iCu) compound exposure were harvested after six days. The nutritional profile was determined to be significantly disrupted in the roots by 1000 ppm bCu treatment, resulting in a 58.7% reduction in potassium compared to the control. In the shoots, a significant decrease of manganese was observed for 10 and 1000 ppm iCu treatments with 55.7% and 64.2% reductions, respectively. The overall protein content and catalase (CAT) enzymatic activity, however, remained unaffected in either roots or shoots, while an absence of polyphenol oxidase …

Properties Of Titanium Dioxide Nanoparticles Aquesous Dispersions Stabilized By Anionic Surfactants, Anita Vuchkovska

Theses and Dissertations

The stability of titanium dioxide nanoparticles dispersed in aqueous solutions with and without anionic surfactants was investigated as a function of phase separation (sedimentation), particle size at the age of 33 and 303 days, polydispersity at 33 and 303 days, and zeta potential. Mechanical energy in the form of homogenization or mixing with propeller blade mixer was used to wet out the titanium dioxide (TiO2) nanoparticles in the aqueous media and this process was evaluated for the capability of developing a stable dispersion. The ultrasonic waves were used as a second step to form stable dispersions. The research results indicated …

Geometric Analysis Of Insect Wing Vein Network, Jacob White, Ying Hu, Sangjin Ryu, Seunghee Kim, Haipeng Zhang

Department of Mechanical and Materials Engineering: Faculty Publications

An insect wing consists of a thin membrane supported by a system of veins, and flow of blood through the system of veins is critical for maintaining healthy insect wings. Better understanding of the insect wing vein circulation requires to know how the efficiency of blood flow in an insect wing relates to the geometric shape of the vein. Our investigation of the wing vein network of a dragonfly Anax junius follows the idea of Murray’s law, which is established in the study of efficiency of the vein network and the geometric shape of the vein. Instead of using the …

Subwavelength Engineering Of Silicon Photonic Waveguides, Farhan Bin Tarik

All Dissertations

The dissertation demonstrates subwavelength engineering of silicon photonic waveguides in the form of two different structures or avenues: (i) a novel ultra-low mode area v-groove waveguide to enhance light-matter interaction; and (ii) a nanoscale sidewall crystalline grating performed as physical unclonable function to achieve hardware and information security. With the advancement of modern technology and modern supply chain throughout the globe, silicon photonics is set to lead the global semiconductor foundries, thanks to its abundance in nature and a mature and well-established industry. Since, the silicon waveguide is the heart of silicon photonics, it can be considered as the core …

Control Mechanisms For Adaptive Nanoscale Devices, David Arredondo

Nanoscience and Microsystems ETDs

Nanotechnology promises to revolutionize many areas of applied science including materials, synthetic biology, and medicine. Devices may consist of solution-phase information processing systems or molecular robots. Of particular interest are DNA-based systems due to their composability and relatively simple interactions that are suited to bottom-up design. This work introduces high-level designs of robust control mechanisms for nanoscale devices with immediate applications in molecular computing, synthetic biology, and DNA robotics.

Nanoscale systems are dominated by probabilistic chemical behavior, so engineers must take careful consideration to produce predictable systems. Probabilistic behavior in chemical reaction networks (CRNs) yields deterministic evolution of species concentrations …

Understanding The Role Of Antioxidant Nanoparticles In Improving The Outcome Of Secondary Injury In Traumatic Brain Injury, Aria W. Tarudji

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Following traumatic brain injury (TBI), excess reactive oxygen species (ROS) and other free radicals are released, inducing the cascade of secondary injury that exacerbate the outcomes of TBI. Antioxidant nanoparticles (ANPs) have shown promising outcomes in reducing the progression of TBI, which may be due to the higher accumulation and retention of ANPs in the injured brain. However, there is limited knowledge of: 1) antioxidant activities needed in TBI treatment, 2) correlation between longer retention, bioavailability, and target engagement with antioxidant treatments, and 3) sexual dimorphism to ANP treatments.

This dissertation assesses multiple ANPs with various scavenging activities and durations …