Physical Sciences and Mathematics Commons^™

Radiative Transfer Using Path Integrals For Multiple Scattering In Participating Media, Paul Michael Kilgo

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The theory of light transport forms the basis by which many computer graphic renderers are implemented. The more general theory of radiative transfer has applications in the wider scientific community, including ocean and atmospheric science, medicine, and even geophysics. Accurately capturing multiple scattering physics of light transport is an issue of great concern. Multiple scattering is responsible for indirect lighting, which is desired for images where high realism is the goal. Additionally, multiple scattering is quite important for scientific applications as it is a routine phenomenon. Computationally, it is a difficult process to model. Many have developed solutions for hard …

Investigating Materials That Promote New Organic Methodology And Remediation Of Volatile Organic Compounds, Mckenzie Louise Campbell

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The need for environmentally safe reagents for the promotion of organic transformations is critical in order to reduce hazardous waste and byproducts associated with industrial-scale chemical processes. We have developed two practical methods that obviate the need for harsh oxidative and toxic brominating reagents in electrophilic halogenation reactions.

In our hands, a catalytic loading of the inexpensive, commercially available V2O5 (~$0.25/g) promotes the bromolactonization of a series of substituted alkenoic acids in isolated yields up to 97% by means of the in situ generation of bromenium (Br+) from bromide (Br−) at room temperature. This process obviates the need for molecular …

Vanadium Diselenide: On The Verge Of Charge Density Wave, Menghan Zhou

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Charge density wave (CDW) is a many-body state of matter in which both lattice and electron density are modulated by a new periodicity. CDW features discrete translational symmetry breaking, and mostly occurs in low-dimensional materials. Although CDW behaviors have been found in many materials, the underlying mechanism and the driving forces of CDW transition are still unclear. In particular, the origin of CDW in two-dimensional materials, especially in layered transition metal dicalchogenides (TMDCs), may be distinct from that in one-dimensional materials.

In this dissertation, the CDW transition in VSe2, a layered TMDC material, is explored. Density functional theory (DFT) calculations …

Numerical Study For Non-Newtonian Fluid-Structure Interaction Problems, Shuhan Xu

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In this work, we consider non-Newtonian fluid structure problems, which have significant applications in biology and industry. Numerical approximation schemes are developed based on the Arbitrary Lagrangian-Eulerian (ALE) formulation of the flow equations. A spatial discretization is accomplished by the finite element method, and the time discretization is carried out by the implicit Euler method. We first consider a fluid-structure interaction problem that consists of a two-dimensional viscoelastic flow and a one-dimensional structure equation. We show how the system can be decoupled and how each subproblem can be solved using interface conditions. Numerical results of different algorithms are presented, showing …

Part 1: One Minute Peptoid Synthesis, From Peptoid Oligomers To Peptoid Polymers - Part 2: Synthesis Of Creatine Derivatives, Dan Y. Dong

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Part 1:

Peptoids are isomers of peptides where the side chains are on the nitrogens instead of the carbons, which have been developed for a variety of biomedical, nano, and materials applications. Conventional peptoid synthesis uses molar concentrations of reagents and hours of reaction time per residue, thus practically limiting the lengths of peptoids. Recently, we have managed to improve yields and make peptoids of unprecedented lengths while reducing the reaction times and concentrations of reagents. Indeed, we have demonstrated that the conventional longer reaction times degrade the peptoids and lead to lower purities. In addition, by using microwave conditions, …

Cloud Abstraction Libraries: Implementation And Comparison, Udit Agarwal

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Vendor lock-in makes it difficult for an organization to port their services, application or data. Cloud providers are in race to provide the best-in-class storage, networking and compute resources. Many organizations are moving towards micro-services and cloud services architecture. It is very important for an infrastructure platform to offer a high-quality cloud computing environment consistently across multiple cloud platforms. To enable this, a collaborative yet an independent cloud abstraction service is required. The cloud abstraction library should support the basic use cases of delivery pipeline, service management, cloud operations and security service. Cloud interoperability standards helps to improve availability and …

Defect Assisted Growth Of Copper-Silicide Nanostructures On Si(100) And Si(111), Endu Sekhar Srinadhu

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As the dimensions of the smallest feature on the integrated circuit has minia-turized into the range of tens of nanometers, patterning of highly ordered nanos-tructures with tunable size and shape in large scale on the surface of substrate is highly demanding and increasingly challenges the limits of nanolithography. To over-come the conventional lithographic limitations, self assembled methods have been explored. While strain driven self assembly is widely viewed as a promising technique for patterning at the nanoscale, to follow this approach and create structures in a desired manner, a reliable means to engineer and characterize the shape and sizes of …

Development Of Sulfur And Selenium Halogen Bonded Synthons And Mechanosynthesis Of Halogen Bonded Cocrystals, Adam Michael Siegfried

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The halogen bond, XB, has been known since the nineteenth century. A XB involves the donation of electron density from a donor such as N, O, S, or Se to an electropositive region on another atom typically iodine or bromine. XB acceptors are Lewis bases and XB donors are Lewis acids keeping terminology hydrogen bonding. The highly directional characteristic of the halogen bond paired with phenyl embrace interactions provide very useful supramolecular synthons allowing for the engineering of cocrystals with specific directional bonding motifs.

Nitrogen electron acceptors such as quinoxaline, phenazine, 4,4’-bipyridine, and 4,4’-dimethyl-2,2’-bipyridine are cocrystallized with 1,4-diiodotetrafluorobenzene (1,4-F4DIB), 1,4-difluorotetraiodobenzine …