Isomerization is a synthetically useful technique to form the more stable internal alkene from terminal alkene feedstock. Unfortunately, these transformations form a variety of isomers without catalyst control. Z alkenes are thermodynamically challenging to form compared to their E counterparts but are useful in pharmaceutical, fragrance, and flavor industries, making them sought-after products. Therefore, catalysts targeting specific regio- and stereoisomers, particularly Z alkenes, will benefit many fields. This work analyzes several Mo(0) complexes as Z-2-alkene selective isomerization catalysts. Particular focus has been given to cis-Mo(CO)4(PCy3)(piperidine) due to easy purification and characterization. Substantial improvement to reported Z selectivities have been obtained with this complex, though disadvantages exist. To have a clearer understanding of the mechanism and source of Z selectivity, DFT analysis was completed, and a mechanism proposed. A rare rotation of hydride and carbonyl ligands was found, only reported in one prior Mo complex, that facilitates the isomerization. Key characteristics were discovered that will be applied to develop future iterations with the goal of reducing, or removing, the disadvantages of this system. / Chemistry

An algorithm has been developed that enables improved the resolution wind estimates from SeaWinds data. This thesis presents the development of three key portions of the high resolution wind retrieval algorithm: Compositing individual σ-0 measurements and Kp, Retrieved wind bias correction, and ambiguity selection for high resolution winds. The high resolution winds produced by this algorithm are expected to become a useful resource for scientists and engineers studying the ocean winds. The high resolution wind retrieval algorithm allows wind to be retrieved much closer to land than is available from the low resolution winds estimated from the same scatterometer by the Jet Propulsion Laboratory. The high resolution winds allow features such as the eye of hurricanes to be seen with much greater detail than was previously possible.

Three-dimensional (3D) planetary general circulation models (GCMs) have been derived from global climate models used to project 21st century changes in Earth's climate. GCMs are used to address questions regarding the climate-and habitability aspects of terrestrial planets within the solar system and assess the habitability of planets outside of the solar system, so called exoplanets. The development of GCMs has given rise to various results for concepts essential for determining potential habitable exoplanets such as the Habitable zone, hence intercomparison studies are of interest. In this project, the climate of an exoplanet with a static thermodynamic ocean will be modelled using ROCKE-3D, an open-source (3D) GCM developed at the NASA Goddard Institute for Space Studies. This is done in order to simulate the climate and examine how the simulations compare to other GCMs. The climate simulation will also be applied to an Earth-like planet in order to determine how an Earth-like climate will impact the results. We find that the climate on a rapidly rotating Aquaplanet receiving a G-star spectral energy distribution is surprisingly Earth-like. By contributing to a higher albedo, the ocean ice fraction of a rapidly rotating Aquaplanet was shown to impact the temperature and humidity structure considerably, despite the absence of Ocean Heat Transport. However, small differences between the simulations with and without sea ice were found for a tidally locked Aquaplanet receiving a M-star spectral energy distribution, which indicates that ROCKE-3D is not shutting off sea ice properly. Generally, ROCKE-3D shows similar results as CAM4 for the G-star runs and for the M-star, ROCKE-3D shows similar results to LMDG. / Tredimensionella (3D) planetariska allmänna cirkulationsmodeller (GCM) har härletts från de globala klimatmodeller som används för att projicera 2000-talets förändringar i jordens klimat. GCM används för att bemöta frågor om klimat- och beboelighetsaspekter av jordlika planeter inom solsystemet och bedöma beboeligheten för planeter utanför solsystemet, så kallade exoplaneter. Utvecklingen av GCM har gett upphov till olika resultat för begrepp som är väsentliga för att bestämma potentiella beboeliga exoplaneter såsom den beboerliga zonen, därför är jämförande studier av intresse. I detta projekt kommer klimatet för en exoplanet med ett statiskt termodynamiskt hav att modelleras av ROCKE-3D, en öppen källkod (3D) GCM utvecklad vid NASA Goddard Institute for Space Studies. Detta görs för att simulera klimatet och undersöka hur simuleringarna står sig i jämförelse med andra GCMs. Klimatsimuleringen kommer också att tillämpas på en jordliknande planet för att avgöra hur ett jordliknande klimat kommer att påverka resultaten. Vi finner att klimatet på en snabbt roterande vattenplanet som mottar en G-stjärnig spektral energifördelning är överraskande jordliknande. Genom att bidra till ett högre albedo visade havsisfraktionen av en snabbt roterande Aquaplanet att påverka temperatur- och fuktstrukturen avsevärt, trots frånvaron av havsvärmetransport. Små skillnader mellan simuleringarna med-och utan havsis påvisades för en tidvattenlåst vattenplanet som mottar en M-stjärnig spektral energifördelning, vilket tyder på att ROCKE-3D inte bortser havsis ordentligt. Generellt visar ROCKE-3D liknande resultat som CAM4 för en G-stjärna. För en M-stjärna visar ROCKE-3D liknande resultat som LMDG.

This dissertation introduces new heuristic methods for the 0-1 multi-dimensional knapsack problem (0-1 MKP). 0-1 MKP can be informally stated as the problem of packing items into a knapsack while staying within the limits of different constraints (dimensions). Each item has a profit level assigned to it. They can be, for instance, the maximum weight that can be carried, the maximum available volume, or the maximum amount that can be afforded for the items. One main assumption is that we have only one item of each type, hence the problem is binary (0-1). The single dimensional version of the 0-1 MKP is the uni-dimensional single knapsack problem which can be solved in pseudo-polynomial time. However the 0-1 MKP is a strongly NP-Hard problem. Reduced cost values are rarely used resources in 0-1 MKP heuristics; using reduced cost information we introduce several new heuristics and also some improvements to past heuristics. We introduce two new ordering strategies, decision variable importance (DVI) and reduced cost based ordering (RCBO). We also introduce a new greedy heuristic concept which we call the "sliding concept" and a sub-branch of the "sliding concept" which we call "sliding enumeration". We again use the reduced cost values within the sliding enumeration heuristic. RCBO is a brand new ordering strategy which proved useful in several methods such as improving Pirkul's MKHEUR, a triangular distribution based probabilistic approach, and our own sliding enumeration. We show how Pirkul's shadow price based ordering strategy fails to order the partial variables. We present a possible fix to this problem since there tends to be a high number of partial variables in hard problems. Therefore, this insight will help future researchers solve hard problems with more success. Even though sliding enumeration is a trivial method it found optima in less than a few seconds for most of our problems. We present different levels of sliding enumeration and discuss potential improvements to the method. Finally, we also show that in meta-heuristic approaches such as Drexl's simulated annealing where random numbers are abundantly used, it would be better to use better designed probability distributions instead of random numbers.

The first part of the thesis includes examining inorganic/organic hybird layered solids, also termed “clay mimics.” Transmission and scanning electron microscopy techniques were used to characterize particles before and after intercalation of pyridine based groups. The particle sizes, shape, and surface morphology were studied for a control and five intercalated species, and evidence for change in particle size and shape was found. The second part of the thesis involves a study in the area of inorganic-organic perovskite networks. Variations in the nature of the cationic organic portion as well as the divalent metal halides have been used to try to better predict the type of network formed. In the work reported here, metal halide and ortho-substituted anilines are combined to relate metal halide network dimensionalities to the steric demands of the ortho- substituents on aniline species. The study involved divalent d10 metal halides, and the halides used were: chloride, iodide, and bromide. The anilines used had varied substituents ortho- to the ammonium group, in order to encompass a wide range of substituents. The goal of the study was to determine if the nature of the ortho-substituent caused consistent effects on the resulting crystal structure. Crystals were grown using slow evaporation techniques and viable crystals were characterized using single crystal X-ray diffraction.

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Lipid transfer proteins (LTPs) constitute a pervasive class of small proteins implicated in many biological and physiological processes, including seed development, germination, cuticle formation, and abiotic stress responses. In this study, we explored the role of Arabidopsis LTP12 protein in mitigating environmental stresses. To address this, we analyzed the T-DNA knockout mutant ltp12, focusing on its responses to salinity and osmotic stress. Utilizing antioxidant enzyme assays, phenotypic analyses (including water loss, chlorophyll content, seed germination rates, root length, and relative water content), and lipid profile analysis via Thin Layer Chromatography (TLC), we found that ltp12 mutants showed reduced catalase and peroxidase activities and poorer hydration, chlorophyll content, germination, and growth under stress, compared to wild-type Col-0 plants. Mutants delayed vegetative-to-floral phase transition compared to wild-type. Additionally, lipid analysis indicated that the wild-type plants had increased phospholipids under high osmotic stress, suggesting LTP12's involvement in lipid reorganization during stress responses.

Traffic incidents routinely impact the flow of vehicles on roadways. These incidents need to be identified, and responded to in a timely fashion in order to keep traffic moving safely and efficiently. One of the main areas of transportation research that remains of contemporary interest is the study of travel times. Travel time information technologies, until very recently, have not been efficient enough to provide instantaneous information for managing traffic flow. The Virginia Department of Transportation (VDOT) currently operates a number of surveillance technologies. Of particular interest to us are Automatic Vehicle Identification (AVI) tag readers to assimilate travel time information. One of VDOT's latest research thrusts has been to develop efficient algorithms for estimating link travel times using such advanced technologies. To achieve this purpose, VDOT is currently monitoring volunteer tagged cars by using AVI tag readers fixed at certain specific locations. This thesis focuses on devising an efficient methodology to capture as much travel time information as possible, by solving a Reader Location Problem that maximizes the benefit accruing from measuring travel time variability with respect to freeways. This problem is formulated as a quadratic 0-1 optimization problem. The objective function parameters in the optimization problem represent certain benefit factors resulting from the ability to measure travel time variability along various origin-destination paths. A simulation study using the INTEGRATION package is performed to derive these benefit factors for various types of freeway sections, and two composite functions that measure benefits for O-D paths that are comprised of several such sections are presented. The simulation results are presented as generic look-up tables, and can be used for any freeway section for the purpose of computing the associated benefit factor coefficient. An optimization approach based on the Reformulation-Linearization Technique coupled with Semidefinite Programming concepts is designed to solve the formulated reader location problem. This approach can be used to derive alternative equivalent formulations of the problem that vary in the degree of tightness of their underlying linear programming relaxations. Four such model representations are explored by using the software package, AMPL-CPLEX 6.5.3, to solve them for some sample transportation networks. The sensitivity of the reader locations to the different proposed benefit factor composite functions is also investigated. The results indicate that the first level continuous RLT relaxation to problem RL produces a tight underlying representation and that the optimal solution obtained for this relaxation tends to be very close to the actual integer optimum. Moreover, it is found that the optimal locations of the readers are insensitive to either the traffic, or the benefit factor used, or the density of the graph, when these factors are considered individually. However, a combination of two or more of these factors can lead to a change in the optimal locations of the readers. / Master of Science

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