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2015

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Open Access Dissertations

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Full-Text Articles in Physical Sciences and Mathematics

Homogeneous And Heterogeneous Rhenium Catalysts For Sustainable Transformations Of Polyols, Alcohols, And Amines, Jing Yi Apr 2015

Homogeneous And Heterogeneous Rhenium Catalysts For Sustainable Transformations Of Polyols, Alcohols, And Amines, Jing Yi

Open Access Dissertations

Biomass-derived molecules, such as sugar polyols and lignin, are promising feedstock for making small and useful organics (SUO) and high value-added organics (HVO). However, the high oxygen to carbon ratio (C:O ≈ 1) prohibits the direct use of biomass-derived molecules as energy carriers and chemicals. Deoxygenation of polyols has become an important challenge in the utilization of biomass resources. Oxorhenium complexes show excellent oxophilicity to transfer oxygen and deoxygenate alcohols. Oxorhenium(VII) complexes can efficiently catalyze the transformation of glycerol to allyl alcohol, acrolein, and propanal. The volatile SUO products were easily separated from the nonvolatile residues via simple distillation. Based …

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Modeling, Optimization, And Sensitivity Analysis Of A Continuous Multi-Segment Crystallizer For Production Of Active Pharmaceutical Ingredients, Bradley James Ridder Jan 2015

Modeling, Optimization, And Sensitivity Analysis Of A Continuous Multi-Segment Crystallizer For Production Of Active Pharmaceutical Ingredients, Bradley James Ridder

Open Access Dissertations

We have investigated the simulation-based, steady-state optimization of a new type of crystallizer for the production of pharmaceuticals. The multi-segment, multi-addition plug-flow crystallizer (MSMA-PFC) offers better control over supersaturation in one dimension compared to a batch or stirred-tank crystallizer. Through use of a population balance framework, we have written the governing model equations of population balance and mass balance on the crystallizer segments. The solution of these equations was accomplished through either the method of moments or the finite volume method. The goal was to optimize the performance of the crystallizer with respect to certain quantities, such as maximizing the …

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Structure-Activity Relationships For The Water-Gas Shift Reaction Over Supported Metal Catalysts, Kaiwalya D. Sabnis Jan 2015

Structure-Activity Relationships For The Water-Gas Shift Reaction Over Supported Metal Catalysts, Kaiwalya D. Sabnis

Open Access Dissertations

The Water-Gas Shift (WGS) reaction (CO + H2O → CO2 + H2) is an important chemical process for industrial hydrogen production. The overall goal of this project is to use kinetic experiments and in situ characterization techniques in tandem, in order to derive structure-activity relationships for various catalytic systems. These relationships facilitate the rational catalyst design by identification of catalyst descriptors. In order to establish such relationships, various studies were undertaken, such as (i) effect of transition admetals on the WGS catalysis by molybdenum carbide (ii) effect of residual oxygen content on the performance of …

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Measurement Of The Drell--Yan Differential Cross Section With The Cms Detector At The Lhc, Alexey Svyatkovskiy Jan 2015

Measurement Of The Drell--Yan Differential Cross Section With The Cms Detector At The Lhc, Alexey Svyatkovskiy

Open Access Dissertations

This thesis describes precision measurements of electroweak interactions in a new energy regime and the application of these measurements to improve our understanding of the structure of the proton. The results are based on proton-proton collision data at √s = 7 and 8\TeV recorded with the Compact Muon Solenoid detector at the CERN Large Hadron Collider during the first years of operation. Measurements of the differential Drell–Yan cross section in the dimuon and dielectron channels covering the dilepton mass range of 15 to 2000\GeV and absolute dilepton rapidity from 0 to~2.4 are presented. The Drell–Yan cross section in proton-proton …

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A 2-Categorical Extension Of The Reshetikhin--Turaev Theory, Yu Tsumara Jan 2015

A 2-Categorical Extension Of The Reshetikhin--Turaev Theory, Yu Tsumara

Open Access Dissertations

We concretely construct a 2-categorically extended topological quantum field theory that extends the Reshetikhin-Turaev TQFT to cobordisms with corners. The source category will be a well chosen 2-category of decorated cobordisms with corners and the target bicategory will be the Kapranov-Voevodsky 2-vector spaces.

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Advanced Wireless Communications Using Large Numbers Of Transmit Antennas And Receive Nodes, Junil Choi Jan 2015

Advanced Wireless Communications Using Large Numbers Of Transmit Antennas And Receive Nodes, Junil Choi

Open Access Dissertations

The concept of deploying a large number of antennas at the base station, often called massive multiple-input multiple-output (MIMO), has drawn considerable interest because of its potential ability to revolutionize current wireless communication systems. Most literature on massive MIMO systems assumes time division duplexing (TDD), although frequency division duplexing (FDD) dominates current cellular systems. Due to the large number of transmit antennas at the base station, currently standardized approaches would require a large percentage of the precious downlink and uplink resources in FDD massive MIMO be used for training signal transmissions and channel state information (CSI) feedback. First, we propose …

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Instrumentation And Development Of A Mass Spectrometry System For The Study Of Gas-Phase Biomolecular Ion Reactions, Ziqing Lin Jan 2015

Instrumentation And Development Of A Mass Spectrometry System For The Study Of Gas-Phase Biomolecular Ion Reactions, Ziqing Lin

Open Access Dissertations

Gas-phase reactions of biomolecular ions are highly relevant to the understanding of structures and functions of the biomolecules. Mass spectrometry is a powerful tool in investigating gas-phase ion chemistry. Various mass spectrometers have been developed to explore ion/molecule reactions, ion/ion reactions, ion/photon reactions, ion/radical reactions etc., both at atmospheric pressure and in vacuum. In-vacuum reactions have an advantage of involving pre-selecting the ions for the reactions using a mass analyzer. Over the decades, a variety of mass analyzers have been employed in the research of ion chemistry. Hybrid configurations, such as quadrupole ion trap with a time-of-flight and or a …

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Synthetic Steganography: Methods For Generating And Detecting Covert Channels In Generated Media, Philip Carson Ritchey Jan 2015

Synthetic Steganography: Methods For Generating And Detecting Covert Channels In Generated Media, Philip Carson Ritchey

Open Access Dissertations

Issues of privacy in communication are becoming increasingly important. For many people and businesses, the use of strong cryptographic protocols is sufficient to protect their communications. However, the overt use of strong cryptography may be prohibited or individual entities may be prohibited from communicating directly. In these cases, a secure alternative to the overt use of strong cryptography is required. One promising alternative is to hide the use of cryptography by transforming ciphertext into innocuous-seeming messages to be transmitted in the clear. ^ In this dissertation, we consider the problem of synthetic steganography: generating and detecting covert channels in generated …

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Calculus For Decision Systems, Jorge Antonio Samayoa Ranero Jan 2015

Calculus For Decision Systems, Jorge Antonio Samayoa Ranero

Open Access Dissertations

The conceptualization of the term "system" has become highly dependent on the application domain. What a physicist means by the term system might be different than what a sociologist means by the same term. In 1956, Bertalanffy [1] defined a system as " a set of units with relationships among them". This and many other definitions of system share the idea of a system as a black box that has parts or elements interacting between each other. This means that at some level of abstraction all systems are similar, what eventually differentiates one system from another is the set of …

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Novel Techniques For Quasi Three-Dimensional Nanofabrication Of Transformation Optics Devices, Paul R. West Jan 2015

Novel Techniques For Quasi Three-Dimensional Nanofabrication Of Transformation Optics Devices, Paul R. West

Open Access Dissertations

Current nanofabrication is almost exclusively limited to top-down, two-dimensional techniques. As technology moves more deeply into the nano-scale regime, fabrication of new devices with quasi three-dimensional geometries shows great potential. One excellent example of an emerging field that requires this type of non-conformal 3D fabrication technique is the field of Transformation Optics. This field involves transforming and manipulating the optical space through which light propagates. Arbitrarily manipulating the optical space requires advanced fabrication techniques, which are not possible with current two-dimensional fabrication technologies. One step toward quasi three-dimensional nanofabrication involves employing angled deposition allowing new growth mechanisms, and enabling a …

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