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Full-Text Articles in Physics
P1: Synthesis Optimization And Characterization Of Polymeric Microgels, Samantha Tietjen, Samantha Hudson
P1: Synthesis Optimization And Characterization Of Polymeric Microgels, Samantha Tietjen, Samantha Hudson
Undergraduate Research Posters 2017
Microgels are spherical particles suspended in solution, comprised of crosslinked polymer chains. Due to the amphiphilic property of the parent polymer, microgels display a temperature dependent de-swelling property, and therefore have the potential to be used for drug delivery. In this case, microgels were synthesized using hydroxypropyl cellulose (HPC) polymer and divinyl sulfone (DVS) cross-linker, as well as dodecyltrimethylammonium bromide (DTAB) surfactant to decrease particle size and promote microgel monodispersity. Synthesized particles were then characterized using dynamic light scattering (DLS) for both temperature and angle dependence to determine hydrodynamic radius, Rh, at a range of temperatures showing a transition from …
Purification And Crystallization Trials Of The Dihydroorotase From Methanococcus Jannaschii, Amy K. Dadisman
Purification And Crystallization Trials Of The Dihydroorotase From Methanococcus Jannaschii, Amy K. Dadisman
Undergraduate Research Posters 2017
Dihydroorotase is the enzyme that catalyzes the third step of the de novo biosynthesis of pyrimidines. M. jannaschii is a hyperthermophillic archaeon that can serve as a model organism for research purposes. This experiment is a first step toward elucidating the structure of the dihydroorotase in M. jannaschii. The enzyme was purified by salting out and heating the solution and then putting the supernatant through cation exchange chromatography and hydrophobic interaction chromatography. Twenty-four conditions were tested to determine if a crystal of dihydroorotase could be formed. Two of these conditions led to preliminary crystal formation. These findings can be utilized …
Achieving Atomically Smooth Surfaces And Ultra Sharp Platinum-Iridium Tips For Deposition Of Organic Molecules, William Myers
Achieving Atomically Smooth Surfaces And Ultra Sharp Platinum-Iridium Tips For Deposition Of Organic Molecules, William Myers
Undergraduate Research Posters 2017
Organic materials are used in traditional solar cells and in flexible electronics. Unfortunately, the conductivities of organic semiconductors are significantly lower than their inorganic counterparts. This project examines the crucial first steps to enhancing the conductivities of these organic materials by crystallization via surface reconstructions. For this, the surface must be not only atomically smooth, but also atomically clean because there must be both enough room for the molecule to lie on and no possible adsorbates for the deposited material to react with. In this work, we looked at two substrates, gold and silicon. For the gold, we examined two …
P1: How High Does The Lower Atmosphere Go?, Vladimir Sworski, Justin Flaherty
P1: How High Does The Lower Atmosphere Go?, Vladimir Sworski, Justin Flaherty
Undergraduate Research Posters 2017
The Atmospheric Boundary Layer (ABL), consisting of the bottom few kilometers of the troposphere, is a region with strong mixing of moisture and winds. This region's activity has a large impact on weather and climate models. In this study, we use a high resolution computer model: Large Eddy Simulation (LES). Statistics produced require a strong understanding of the height of the ABL. The purpose of this study was to create a method for determining this height accurately and consistently, as previous models demonstrated significant error.
P3: What Determines The Shape Of A Cloud?, William Calabrase
P3: What Determines The Shape Of A Cloud?, William Calabrase
Undergraduate Research Posters 2017
Current climate models and weather forecasts suffer due to an uncertainty associated with the behavior of clouds, which directly impact the energy exchange between the earth and the Sun. This impact is determined in part by the shape of the clouds, thereby making the study of what affects cloud shape an area of interest. To characterize the shape of cumulus clouds we study the behavior of the cloud overlap ratio, or the ratio between the average cloud fraction and projected cloud cover. In this study, we used a high resolution computer model to 1) determine how the cloud overlap ratio …
P1: Using Modified Dean Flow Designs To Increase Mixing Performance, Joshua Clark
P1: Using Modified Dean Flow Designs To Increase Mixing Performance, Joshua Clark
Undergraduate Research Posters 2017
We are using numerical solutions for the Navier-Stokes equations and the concentration - diffusion equation to model fluid flow and reactant distribution in serpentine type channels for micromixers/microreactors development. These mixers exploit centripetal forces on the fluid to induce cross-sectional fluid mixing, aka Dean flows. Various modifications are used to increase the mixing character of these crosssectional flows. We found that the performance of these mixers exceeds that of unmodified channels and we currently assess their performance relative to other state of the art methodologies used to induce mixing on the microscale.
P2: Implementation Of Groove Based Designs For Engineering Fluid Flow In Micromixers, Tahir Butt
P2: Implementation Of Groove Based Designs For Engineering Fluid Flow In Micromixers, Tahir Butt
Undergraduate Research Posters 2017
Mixing on microscale is important for the development of miniaturized chemical reactors that use small quantities of reactants and allow better control over the reaction conditions and products. Nevertheless, achieving rapid mixing in this type of micro-reactors is challenging due to the lack of turbulence and slow diffusion on the microscale. In this work we implement micromixers designs based on surface groove/ridge patterns targeted at inducing cross-sectional flows that both extend the interface between the different reactants, as well as induce chaotic advection. We discuss the fabrication of these structures using soft-lithography in PDMS employing a mold and their optical …
Fabricating Non-Close Packed Colloidal Monolayers For Ion Irradiation Templates, Nandini Padaraju
Fabricating Non-Close Packed Colloidal Monolayers For Ion Irradiation Templates, Nandini Padaraju
Undergraduate Research Posters 2017
Due to their unique properties, anisotropic nanoparticles are desirable components for future applications yet there are few processes capable of fabricating nanoparticle impregnated coatings for the manufacturing environment. Our work seeks to develop new masking techniques for the production of the templated substrates that will induce ordered nanoparticle films. Specifically, we are fabricating non-close packed colloidal monolayers onto silicon substrates, which then serve as the template for ion irradiation. The first steps to creating this monolayer are obtaining a spin-coated poly(vinyl alcohol) (PVA) thin film of ~200 nm and a close-packed colloidal monolayer using a peltier heater. We achieved a …
P2: Reconciling Linear Measurements Of Fractal Cloud Structures, Nicholas Barron
P2: Reconciling Linear Measurements Of Fractal Cloud Structures, Nicholas Barron
Undergraduate Research Posters 2017
Clouds are a large unknown in meteorological predictions. Most of the issue can be derived from the odd shape of clouds. So, in order to correct the measurements of clouds, a thorough investigation of fractal cloud structures must be performed. Using the results from this study, a reconciliation method can then be constructed and applied to linear measurements of clouds.
P2: Developing Methodologies For Wet-Sample Electron Microscopy Imaging, Daniel Terrano, Petru Fodor
P2: Developing Methodologies For Wet-Sample Electron Microscopy Imaging, Daniel Terrano, Petru Fodor
Undergraduate Research Posters 2017
Scanning Electron Microscopy (SEM) is widely used to analyze the size, shape, and composition of material systems. However, using this tool for analyzing systems such as particles suspended in solution requires drastic sample alterations, such as precipitation and fixation. Besides altering their environment, this exposes the particles to the harsh conditions within an electron microscope, such as high vacuum and electron beam exposure. To this end, the first goal of this study was to develop methodologies for imaging wet samples using electron microscopy. This is realized by creating a sandwich structure containing the solution of interest between a partially electron …