Engineering Commons^™

The Effect Of Cupc Nanostructures On The Photo And Electrophysical Characteristics Of The Active Layer P3ht/Pcbm, A. K. Aimukhanov, B. R. Ilyassov, A. K. Zeinidenov, A. V. Zavgorodniy

Eurasian Journal of Physics and Functional Materials

The paper presents the results of a study of the influence of copper phthalocyanine (CuPc) nanostructures on the generation and transfer of charge carriers in the photoactive P3HT/PCBM layer. It was shown that the observed broadening and the shift in the maxima of the absorption spectra of P3HT/PCBM upon the addition of nanostructures to the polymer are associated with an increase in the degree of crystallization of the film. Using the method of impedance spectroscopy, it was found that CuPc nanostructures enhance the rate of recombination of charge carriers, which is probably due to the formation of surface defects. These …

Liver Cancer: Current And Future Trends Using Biomaterials, Sue Anne Chew, Stefania Moscato, Sachin George, Bahareh Azimi, Serena Danti

Health & Biomedical Sciences Faculty Publications and Presentations

Hepatocellular carcinoma (HCC) is the fifth most common type of cancer diagnosed and the second leading cause of death worldwide. Despite advancement in current treatments for HCC, the prognosis for this cancer is still unfavorable. This comprehensive review article focuses on all the current technology that applies biomaterials to treat and study liver cancer, thus showing the versatility of biomaterials to be used as smart tools in this complex pathologic scenario. Specifically, after introducing the liver anatomy and pathology by focusing on the available treatments for HCC, this review summarizes the current biomaterial-based approaches for systemic delivery and implantable tools …

Synergistic Effect Of Nanocoatings For Corrosion And Wear Protection Of Steel Surfaces, Jaime Taha-Tijerina, Laura Peña Parás, Antonio Sánchez Fernández, Demófilo Maldonado Cortés, Pablo Sarmiento Barbosa, Jesús Rolando Adán López

Informatics and Engineering Systems Faculty Publications and Presentations

The purpose of this paper is to evaluate the corrosion and wear protection of a steel substrate by epoxy vinyl ester nanocomposite coatings with Zn and TiO2 nanoparticle fillers. Steel substrates were coated with epoxy vinyl ester nanocomposites, varying Zn and TiO2 nanofiller concentrations and combinations of both nanoparticles. Corrosion resistance was evaluated by salt spray fog test during 480 h, according to ASTM B-117. The degree of damage was obtained quantitatively by measuring the enhancement in corroded area compared to the scribe mark. Tribological evaluation was performed with a ball-on-disk tribotester, according to ASTM G-99. Results showed that the …

Erratum: "Imaging The Three‐Dimensional Orientation And Rotational Mobility Of Fluorescent Emitters Using The Tri‐Spot Point Spread Function", Oumeng Zhang, Jin Lu, Tianben Ding, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

In the original paper, a calibration error exists in the image-formation model used to analyze experimental images taken by our microscope, causing a bias in the orientation measurements in Figs. 2 and 3. The updated measurements are shown in Fig. E1. We have also updated the supplementary material for the original article to discuss the revised PSF model and estimation algorithms (supplementary material 2) and show the revised model and measurements (Figs. S1, S3, S7, S8, and S10–S13).

Shape Effects Of Gold Coated Silica Nanoparticles For Localized Plasmonic Resonance Based Biosensing, Russell Beckerman

ENGS 88 Honors Thesis (AB Students)

Gold coated silica (Au@SiO₂) nanoparticles are promising optical transducers for biosensors due to localized surface plasmonic resonance (LSPR) sensitivity to changes in refractive index. This study investigates the effects of shape, size, and structure on LSPR sensitivity of Au@SiO₂ nanoparticles of spherical, rod, and ellipsoid geometries. Finite-difference time domain simulations in CST were used to examine these key parameters of interest and guided particle synthesis. Simulation and experiments show rod-shaped Au@SiO₂ nanoparticles had maximum sensitivity of 969nm/RIU, an improvement over most particles in current literature. This study examines a method for enhanced LSPR-biosensors that leverages advances …

A Ph-Sensitive Delivery System For The Prevention Of Dental Caries Using Salivary Proteins, Yi Zhu

Electronic Thesis and Dissertation Repository

Dental caries remains one of the most common chronic diseases worldwide. Salivary proteins such as histatins have demonstrated biological functions directly related to tooth homeostasis and prevention of dental caries. However, histatins are susceptible to the high proteolytic activities in the oral environment. Therefore, pH-sensitive chitosan nanoparticles (CNs) have been proposed as potential carriers to target major oral diseases that occur under acidic conditions (e.g. dental caries and dental erosion). Four different types of chitosan polymers were investigated and the optimized CNs successfully loaded histatin 3 and released it selectively under acidic conditions. Through loading the survival time of histatin …

Cell Imaging And Data Analysis For Biomaterial-Mammalian Co-Cultures, Jefferson Pontsler

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Microscopic bioimaging is a useful approach to study cell-biomaterial interactions which are vital to the biomedical application of biomaterials. Through microscopic imaging, numerous cellular responses, such as proliferation, uptake, and death, can be recorded, characterized and analyzed.

In this thesis, I first provided basic introductions to the imaging techniques and analysis tools, especially those that are highly relevant to the studies of biomaterials and cell interactions. I also detailed the adaptation of these techniques and tools in the application of two specific research projects in biomaterials, with special focuses on the imaging and analysis.

The first project assessed the subtle …

Metabolon-Inspired Design Of Multi-Modal Catalytic Cascade, Madelaine Seow Chavez

Chemical and Biological Engineering ETDs

Developing hybrid catalytic systems has been researched for the past decade in an effort to efficiently incorporate catalysts of different modalities in catalytic cascades. It has become imperative to design a cascade system where the catalysts are spatially organized to control the delivery of precursors, intermediates, and products. In this work, we have shown that a molecular catalyst, biocatalyst, and metallic catalyst can be co-localized using a carbonaceous support to create a hybrid catalytic system and complete the oxidation of oxalic acid to create a microchemical reactor. The molecular, pyrene-TEMPO catalyst oxidizes glyoxalic acid to oxalic acid. The enzyme oxalate …

Green Synthesis Nanocomposite Membranes, Dibakar Bhattacharyya, Vasile Smuleac, Rajender S. Varma, Subhas K. Sikdar

Chemical and Materials Engineering Faculty Patents

A nanocomposite membrane includes a macroporous polymer membrane having a plurality of pores. A plurality of metal nanoparticles are synthesized and immobilized within those plurality of pores. The nanoparticles are reduced and capped with a green reducing and capping agent such as green tea extract.

Magnesium Nanocomposites: An Overview On Time-Dependent Plastic (Creep) Deformation, Meysem Haghshenas, Manoj Gupta

Mechanical Engineering Faculty Publications

Magnesium (Mg) nanocomposites are created when nano-size particles are embedded into the Mg (or Mg alloy) matrix. The Mg nanocomposites, cited as high-strength energy-saving materials of future, are a group of emerging materials with excellent combination of strength and ductility and superior specific strength property (strength-to-weight ratio). Having said this, Mg nanocomposites are considered as promising replacement for other structural alloys (i.e. aluminum and titanium) wherever low density and high strength are required, i.e. transportation, aerospace, defense, etc. To be able to apply this group of materials for real components, different failure mechanisms at ambient and elevated temperatures under …

Rapid, Single-Step Protein Encapsulation Via Flash Nanoprecipitation, Shani L. Levit, Rebecca C. Walker, Christina Tang

Chemical and Life Science Engineering Publications

Flash NanoPrecipitation (FNP) is a rapid method for encapsulating hydrophobic materials in polymer nanoparticles with high loading capacity. Encapsulating biologics such as proteins remains a challenge due to their low hydrophobicity (logP < 6) and current methods require multiple processing steps. In this work, we report rapid, single-step protein encapsulation via FNP using bovine serum albumin (BSA) as a model protein. Nanoparticle formation involves complexation and precipitation of protein with tannic acid and stabilization with a cationic polyelectrolyte. Nanoparticle self-assembly is driven by hydrogen bonding and electrostatic interactions. Using this approach, high encapsulation efficiency (up to ~80%) of protein can be achieved. The resulting nanoparticles are stable at physiological pH and ionic strength. Overall, FNP is a rapid, efficient platform for encapsulating proteins for various applications.

Dual Effects Of Tisio4composite Nanoparticles On Dispersionstability And Lubrication Performance Of Vegetable Oil‐In‐Water Emulsions, Reza Taheri, Buyung Kosasih, Hongtao Zhu, Anh Kiet Tieu

Faculty of Engineering and Information Sciences - Papers: Part B

Vegetable oil-in-water emulsions are potential metal-working lubricants. These emulsions are susceptible to oil-water phase separation due to the oil droplets' coalescence. In this study, we enhance the dispersion stability and lubricity of such emulsions with TiSiO4 nanoparticles (NPs). With 1 vol% soybean oil, stable emulsions are obtained with 0.25 to 0.75 wt% NPs, attributed to formation of shielding layers of NPs around the droplets. Lowest friction and wear are obtained without and with 0.25 wt% NPs, respectively. With increasing the NPs' mass fraction, NP-shielded droplets become less attracted to metal surfaces. Association of NPs within boundary film is also found …

Form Stable Phase-Change Materials, Russell Dent, Marjan Kashfipour, Nitin Mehra, Jiahua Zhu

Williams Honors College, Honors Research Projects

This work investigates the use of two different polyols, xylitol (Xyl) and erythritol (Ery), in conjunction with boron nitride (BN) aerogels, for the purpose of creating thermally conductive composites. While the BN filler in Xyl composites achieved a high anisotropic thermal conductivity of up to 4.53 W/m-K at 18.2 weight percent filler loading, they do not exhibit good phase-change material qualities due to a low solidification enthalpy even at low cooling rates. Alternatively, the BN-Ery composites have shown promising results with a solidification enthalpy of 225.14 J/g and a melting enthalpy of 385.84 J/g at a heat rate of 5 …

Synthesis Of Drug Encapsulated Chitosan-Heparin Based Nanoparticles And Release Study, Trent Richwine

Williams Honors College, Honors Research Projects

The main objective of this honor’s project is to encapsulate drugs with different molecular weights inside of chitosan-heparin based nanoparticles (Cs-Hep NPs). Three different drugs with low (NNC), medium (IFN-γ), and large (BSA) molecular weights were chosen in order to compare all types of drugs and how they react with the nanoparticles. Analysis of particle size, zeta potential, and a release study was performed. The release took place over a 168-hour time period and liquid samples were taken throughout. The hypothesis was that the molecular weight of the drug will correlate to the physical properties of the nanoparticles. The results …

Charge Storage In Wo³ Polymorphs And Their Application As Supercapacitor Electrode Material, Vaibhav Lokhande, Abhishek Lokhande, Gon Namkoong, Jin Hyeok Kim, Taeksoo Ji

Electrical & Computer Engineering Faculty Publications

Tungsten oxide is a versatile material with different applications. It has many polymorphs with varying performance in energy storage application. We report simple and facile way to synthesize four phases of tungsten oxide from same precursor materials only by changing the pH and temperature values. Monoclinic, hexagonal, orthorhombic and tetragonal phase obtained, were analyzed and tested for supercapacitor application. The electrochemical analysis of four phases indicates that the hexagonal phase is best-suited electrode material for supercapacitor. The hexagonal phase exhibits higher specific capacitance (377.5 Fg^-1 at 2 mVs^-1), higher surface capacitive contribution (75%), better stability and rate …