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Articles 1321 - 1350 of 2158
Full-Text Articles in Physical Sciences and Mathematics
Empirical Study On Greedy Algorithms For Learning Decomposable Markov Networks, Kyle Jonah Nunez
Empirical Study On Greedy Algorithms For Learning Decomposable Markov Networks, Kyle Jonah Nunez
Honors Theses
No abstract provided.
Oxidation Resistance Studies Of Crain Coatings On 430 Stainless Steel, Kurtis Wickey
Oxidation Resistance Studies Of Crain Coatings On 430 Stainless Steel, Kurtis Wickey
Honors Theses
The requirements of low cost and high-cost temperature corrosion resistance for interconnect plates in solid oxide fuel cell stacks has directed attention to the use of metal plates with oxidation resistant coatings. We have investigated the performance of stainless steel plates with homogenous coatings of CrAIN. The coatings were deposited using RF magnetron sputtering, with Ar as a sputtering gas and N as reactive gas. The Cr/A1 composition ratio in the coatings was varied in a combinatorial approach. The coatings were subsequently annealed in air for up to 25 hours at 800°C. The composition of the coated plates and the …
The Gilboa Dam And Its Possible Failure : What It Means For Nyc And Upstate New York, Kelly C. Owings
The Gilboa Dam And Its Possible Failure : What It Means For Nyc And Upstate New York, Kelly C. Owings
Honors Theses
The majority of the NYC water supply is provided by a system of dams and reservoirs that have been created in upstate New York. As the owner of this water supply system, NYC is responsible for managing each of the dams and reservoirs within the system. This responsibility includes upholding dam regulations in order to ensure the safety of the citizens of the surrounding area and to lesson any environmental impacts that may occur due to the water supply system. Of the 30 dams owned by NYC, however, 25 of them have been identified at a high-hazard level according the …
Effects Of Context Of Natural And Artifactual Objects On Categorization, Linsey Walker
Effects Of Context Of Natural And Artifactual Objects On Categorization, Linsey Walker
Honors Theses
Categorization of animals and vehicles in different contexts was investigated in three experiments using event related potentials (ERPs). The presence of a background and congruency of the background in relation to the object were both manipulated in order to determine the effects of context on visual processing. In Experiment 1, adults were presented with images of animals and vehicles in two conditions: situated in a congruent context (e.g. an animal in a field) and in the absence of a context (an animal in a white homogeneous background). In experiment 2, adults were presented with images of animals and vehicles in …
Foundations And Interpretations Of Quantum Mechanics, Cory Johnson
Foundations And Interpretations Of Quantum Mechanics, Cory Johnson
Honors Theses
The first famous thought experiment of Einstein gives rise to his theories of relativity, the bedrock of modern astrophysics and cosmology. His second famous thought experiment begins the investigation into the foundations of quantum mechanics. It leads to a paradox, inspiring various 'no-go' theorems proven by Bell, Kochen, and Specker. Physicists and philosophers worldwide become increasingly dissatisfied with the probabilistic complementarity interpretation (Born-Bohr) and eventually offer their own accounts of the theory. By the end of the 20th century two alternative approaches stand out as the best candidates: Both the hidden variables interpretation (de Broglie-Bohm) and the many worlds interpretation …
Temperature And Magnetic Field Dependence Of The Electronic Excitations In The Nickel Chain Compound Nino, Lucas Laviolet
Temperature And Magnetic Field Dependence Of The Electronic Excitations In The Nickel Chain Compound Nino, Lucas Laviolet
Honors Theses
Temperature and magnetic field dependent absorbance spectra were taken on the Ni2+ chain compound NINO (Ni(C?H??N?)?NO?(ClO?)) in the range from 8,500 to 25,000 cm-?. The identification of an effective C?v symmetry about the nickel ions is supported by assignment of the low temperature absorbance bands. The intensity of many bands is found to be temperature dependent, and in several bands, a shift to higher energy is observed at lower temperatures. A correlation is noted between the field dependence of the spin forbidden electronic transitions and the magnetic properties of NINO. Below a crossover magnetic field, Hc ? 10 T, the …
Carbon, Nitrogen, Sodium And Phosphorous Concentrations And Ratios In Spartina Alterniflora (Loiser) From Sites Of Various Freshwater And Nutrient Inputs In Coastal Louisiana Wetlands, Margaret Frances Williamson
Carbon, Nitrogen, Sodium And Phosphorous Concentrations And Ratios In Spartina Alterniflora (Loiser) From Sites Of Various Freshwater And Nutrient Inputs In Coastal Louisiana Wetlands, Margaret Frances Williamson
Honors Theses
No abstract provided.
Designing A Green Graduation At Colby College, Alaina J. Clark
Designing A Green Graduation At Colby College, Alaina J. Clark
Honors Theses
Lately, there has been a growing trend of “green” events. The increase in understanding and discussions about the future climate has caused people throughout the world to become concerned about their contribution to climate change. This is true in the Northeast United States as well. Many New England colleges and universities, including Colby College in Waterville, Maine, are becoming leaders in climate change mitigation. As a teaching institution, Colby has recognized that public education is an important part of the solution to the climate crisis. Colby also understands that commencement weekend is an ideal opportunity for climate change education. As …
Hydrologic And Water Quality Assessment Of Miller Run: A Study Of Bucknell University’S Impact, Alison C. Schaffer
Hydrologic And Water Quality Assessment Of Miller Run: A Study Of Bucknell University’S Impact, Alison C. Schaffer
Honors Theses
Human development causes degradation of stream ecosystems due to impacts on channel morphology, hydrology, and water quality. Urbanization, the second leading cause of stream impairment, increases the amount of impervious surface cover, thus reducing infiltration and increasing surface runoff of precipitation, which ultimately affects stream hydrologic process and aquatic biodiversity. The main objective of this study was to assess the overall health of Miller Run, a small tributary of the Bull Run and Susquehanna River watersheds, through an integrative hydrologic and water quality approach in order to determine the degree of Bucknell University’s impact on the stream. Hydrologic conditions, including …
The Determination Of The Electronic Structure And Geometries Of Boron And Boron Mononitrogen Clusters Using An Adaptive, Kink-Based Path Integral Approach To Quantum Mechanics, Shawn Wilkinson
Honors Theses
No abstract provided.
Preconditioned Conjugate Gradient Algorithm, Elena Caraba
Preconditioned Conjugate Gradient Algorithm, Elena Caraba
Honors Theses
No abstract provided.
The Gilboa Dam And Its Possible Failure: What It Means For Nyc And Upstate New York, Kelly C. Owens
The Gilboa Dam And Its Possible Failure: What It Means For Nyc And Upstate New York, Kelly C. Owens
Honors Theses
The majority of the NYC water supply is provided by a system of dams and reservoirs that have been created in upstate New York. As the owner of this water supply system, NYC is responsible for managing each of the dams and reservoirs within the system. This responsibility includes upholding dam regulations in order to ensure the safety of the citizens of the surrounding area and to lesson any environmental impacts that may occur due to the water supply system. Of the 30 dams owned by NYC, however, 25 of them have been identified at a high-hazard level according the …
The Selective Synthesis Of Oxacalix[6]Arenes And The Exploration Of Azacalix[N]Arenes, W. Christian Crannell
The Selective Synthesis Of Oxacalix[6]Arenes And The Exploration Of Azacalix[N]Arenes, W. Christian Crannell
Honors Theses
Calix[n]arenes, cyclIc molecules composed of "n" benzene rings meta-linked by a methylene to form a macrocycle, are very prevalent jn the literature and enjoy a wide range of applications. However, the oxygen bridged and nitrogen bridged systems, oxacalllx[n)arenes and azacalix[n]arenes, respectively, are far less common because they are synthetically challenging. Furthermore, the selective synthesis of oxacalix[6]arene systems has not previously been well documented, but the systems can now be accessed in a facile approach disclosed here. The insight and knowledge gained from the synthesis of oxacalix{6]arenes has provided a foray into the synthesis of azacalix[nlarenes.
Diffeomorphism Invariance In General Relativity, John P. Chung
Diffeomorphism Invariance In General Relativity, John P. Chung
Honors Theses
Einstein's general relativity is a geometrical theory of gravity in which the effects of gravity are due to the curvature of space and time. In contrast, all of the other fundamental particle interactions are described as quantum field theories that are invariant under gauge transformations. In efforts to unify gravity with these other particle theories, it is desirable to reexpress Einstein's general relativity as a gauge theory. The gauge symmetry in Einstein's theory can be identified as invariance under diffeomorphism transformations. This work examines the nature of this symmetry, how it is implemented, and how it behaves as a gauge …
Carbon Neutrality At Colby College, Jamie K. O’Connell
Carbon Neutrality At Colby College, Jamie K. O’Connell
Honors Theses
Carbon neutral is a term used to describe any organization, entity, or process that has a net greenhouse gas (GHG) emissions level of zero (Dautremont-Smith et al. 2007a). Since carbon neutrality only requires a net greenhouse gas emissions level of zero, organizations do not need to eliminate all carbon pollution to become carbon neutral. Net emissions differ from gross emissions in that gross emissions are the sum of all emissions released by the individual or entity, whereas net emissions are equivalent to the gross emissions minus any carbon offsets. A carbon offset is any activity that reduces carbon emissions so …
Diode Lasers For Use In Experiments On Cold Rydberg Atoms, Bill Whitledge
Diode Lasers For Use In Experiments On Cold Rydberg Atoms, Bill Whitledge
Honors Theses
This project was to measure the atomic density of (85)Rb atoms in a magneto optical trap using a low-intensity probe laser. Additionally, a dark spontaneous force optical trap was constructed in an attempt to boost the trap density. The dark spot failed to appreciably increase the overall trap density (which remained steady at - N = 10^10 atoms/cm^3) but it did increase the density of dark-state atoms in the trap by an order of magnitude. This is a useful result since many experiments on cold Rydberg atoms involve exciting atoms starting in the ground state rather than the first excited …
Photochemical Generation And Intramolecular Chemistry Of Β-Alkoxycarbenes, Kimberly Graves
Photochemical Generation And Intramolecular Chemistry Of Β-Alkoxycarbenes, Kimberly Graves
Honors Theses
The photolytic phenanthrene-based precursors for both β-methoxycarbene and β-ethoxycarbene were synthesized with and without a deuterium label attached to the a carbon. The incorporation of this deuterium label allowed distinction between a 1, 2-H shift and a 1, 2-O shift pathway to the respective alkyl vinyl ether, without the influence of a primary kinetic isotope effect. Photolyses of these precursors gave rearrangement products of the expected β-alkoxycarbenes. In the case of β-methoxycarbene, no methyl vinyl ether was observed due to its volatility. However, the appearance of aldehyde peaks in the NMR spectra, from an apparent further rearrangement to acetaldehyde through …
Interactions Of Electrons And Rydberg Atoms In Ultra-Cold Plasmas, Cristian Vesa
Interactions Of Electrons And Rydberg Atoms In Ultra-Cold Plasmas, Cristian Vesa
Honors Theses
This thesis discusses an experimental technique for investigating electron temperature control by Rydberg atoms in ultra-cold plasmas. The objective we set ourselves was twofold. Firstly, we sought to gain an insight into the processes whereby the creation of Rydberg atoms within the plasma lengthens the lifetime of the plasma. To this end, we created the plasma using a Littman dye laser and subsequently, at a variable time delay, we excited neutral atoms in the plasma to specific Rydberg states using a narrow bandwidth pulsed dye laser. Secondly, we employed radio-frequency (rf) electric fields to excite electron oscillations within the plasma …
Effect Of Observed Biological And Non-Biological Movement On Human Action And Coordination, Walter L. Campbell
Effect Of Observed Biological And Non-Biological Movement On Human Action And Coordination, Walter L. Campbell
Honors Theses
Recently, it has been demonstrated that an individual’s rhythmic limb movements exhibit greater variability when viewing spatially incongruent biological limb movements, but not when viewing spatially incongruent non-biological movements. Some researchers have concluded that a ‘mirror-neuron system’ might mediate the intrinsic bidirectional link between perception and action underlying interpersonal, but not environmental, coordination (e.g., Kilner et al., 2003; Tognoli et al., 2007). The current study aimed to: 1) contest this recent finding; and 2) demonstrate that the self-organized entrainment processes of coupled oscillators can explain the differing influences of biological and non-biological movements. In the first experiment, participants intentionally coordinated …
Phosphorus Primer For Maine’S Lakes, Lindsay B. Philips
Phosphorus Primer For Maine’S Lakes, Lindsay B. Philips
Honors Theses
Phosphorus plays a major role in aquatic systems and the life that they support. It is a macronutrient that constitutes 0.5lf microorganisms and zooplankton by mass. Phosphorus is of great importance in terrestrial, agricultural, and plant systems as a macronutrient, and when it comes to aquatic systems, we tend to look at phosphorus in terms of its influence on lake primary productivity. Lakes are often phosphorus sinks because they are maintained by hydrological sources that are capable of causing nutrient influx. To understand phosphorus cycling in lake systems, it is important to consider the many sources and forms of phosphorus …
Reactions Of Atomic Carbon With Acid Chlorides, Daniel B. Herrick
Reactions Of Atomic Carbon With Acid Chlorides, Daniel B. Herrick
Honors Theses
This thesis is the first report of reactions of atomic carbon with acid chlorides. Carbon is known to react with phosgene to afford dichlorocarbene. We report a similar reaction with carbon and acid chlorides, generating alkylchlorocarbenes. We examine both the nature of the carbene products generated through deoxygenation and the general reactivity of carbon with the acid chlorides. We report two ways in which carbon reacts with acid chlorides. First, as expected from prior work with phosgene, carbon deoxygenates the carbonyl group yielding alkylchlorcarbenes, which rearrange as expected. Second, carbon abstracts the chlorine, and generates the acyl radical, which, in …
Pressure Perturbation Calorimetry And Guest-Host Chemistry Of Ndmg And N-Map With P-Sulfonatocalix[6]Arene, Cassandra Newell
Pressure Perturbation Calorimetry And Guest-Host Chemistry Of Ndmg And N-Map With P-Sulfonatocalix[6]Arene, Cassandra Newell
Honors Theses
The aim of this project is to provide an explanation for recently obtained binding constants for two similar guest molecules, NDMG and N-MAP, with a p-sulfonatocalix[6]arene host in ammonium acetate buffer. This work was done primarily using pressure perturbation calorimetry, which is a technique that determines the coefficient of thermal expansion, α, which is in turn related to the solute molecule's effect on the order of the surrounding water molecules. A series of experiments were designed to test the effects of suspected confounding variables on the validity of PPC data. PPC was then used to study NDMG and N-MAP in …
Effects Of The Anticancer Agent Cloretazine On Human Apurinic Endonuclease-1 Activity, Jennifer L. Bushee
Effects Of The Anticancer Agent Cloretazine On Human Apurinic Endonuclease-1 Activity, Jennifer L. Bushee
Honors Theses
The carbamolyating activity of Cloretazine, a novel anticancer prodrug, modifies protein function and acts synergistically with the choroethyalting species, which a1kylales DNA. The reactive subspecies responsible for carbamolylating activity is methyl isocyanate, which reacts with sulfhydryl groups and amines. DNA repair enzymes have been identified as potential targets for the modification by methyl isocyanate; in particular, base excision repair enzymes. Enzymes in DNA base excision repair include DNA polymerase beta (Pol ?) and apurinic/apyrimidic endonucease-l (APE/Ref-1). APE/Ref-1 hydrolyzes the 5' -phosphodiester DNA backbone from an abasic DNA template, where the base was excised by a DNA glycosylase. The entire nucleotide …
Inhibition Of Cellular Thioredoxin Reductase By The Anticancer Prodrug Cloretazine, Tyler R. Schleicher
Inhibition Of Cellular Thioredoxin Reductase By The Anticancer Prodrug Cloretazine, Tyler R. Schleicher
Honors Theses
Sulfonylhydrazines are a class of DNA alkylating drugs which also produce carbamoylating activity in situ. The carbamoylating species is of significance because it has shown to inhibit important thiol-containing enzymes such as glutathione reductase (GR) and thioredoxin reductase (TrxR). TrxR catalyzes dithiol-disulfide exchange reactions on thioredoxin (Trx), which in turn catalyzes other reductive processes such as deoxyribonucleotide biosynthesis. In this study, we demonstrate that TrxR activity is strongly inhibited by the anticancer prodrug Cloretazine both in purified form and in leukemia cell lysates. This inhibition is specific to the carbamoylating activity of methylisocyanate (MiC). In contrast, another important oxidoreductase, glutathione …
Hamiltonian Constraint Analysis Of Vector Field Theories With Spontaneous Lorentz Symmetry Breaking, Nolan L. Gagne
Hamiltonian Constraint Analysis Of Vector Field Theories With Spontaneous Lorentz Symmetry Breaking, Nolan L. Gagne
Honors Theses
Recent investigations of various quantum-gravity theories have revealed a variety of possible mechanisms that lead to Lorentz violation. One of the more elegant of these mechanisms is known as Spontaneous Lorentz Symmetry Breaking (SLSB), where a vector or tensor field acquires a nonzero vacuum expectation value. As a consequence of this symmetry breaking, massless Nambu-Goldstone modes appear with properties similar to the photon in Electromagnetism. This thesis considers the most general class of vector field theories that exhibit spontaneous Lorentz violation-known as bumblebee models-and examines their candidacy as potential alternative explanations of E&M, offering the possibility that Einstein-Maxwell theory could …
Using Azahetercyclic Electrophiles To Synthesize Novel Bicyclooxacalixarenes And Oxacalix[2]N-Hexylnaphthalimide[2]Naphthyridines, Doug Rooke
Honors Theses
Various bicyclooxacalixarenes, tricyclooxacalixarenes and oxacalix[2]N-hexylnapthalimide[2]naphthyridines are synthesized via SnAr condensation. This research has involved synthesis optimization. The oxacalix[2]N-hexylnaphthalimide[2]naphthyridines have exhibited host-guest binding in fluorescence experiments. These compounds have been characterized by NMR spectroscopy as well as single crystal X-ray diffraction.
Eager To Offset: A Case Study In Carbon Offset Forestry, Jason Smith
Eager To Offset: A Case Study In Carbon Offset Forestry, Jason Smith
Honors Theses
"Eager to Offest" aims to look critically at whether businesses in general are engaging in carbon offset forestry as a genuine environmental service or as an investment opportunity benefiting little more than a group's environmental reputation. One industry which has engaged in carbon offset forestry as a part of the voluntary carbon market is the electric utility industry. PowerTree Carbon Company LLC was initiated in April 2004 for the purpose of reforesting 3,609 acres of bottomland hardwood forest in the Lower Mississippi Alluvial Region in Arkansas and Louisiana. Twenty-five electric utilities have founded PowerTree as a limited liability company, jointly …
Separating People And Wildlife: Zoning As A Conservation Strategy For Large Carnivores, Courtney L. Larson
Separating People And Wildlife: Zoning As A Conservation Strategy For Large Carnivores, Courtney L. Larson
Honors Theses
Large carnivores are some of the world’s most difficult species to conserve because of their large spatial requirements, low population density, and high potential for conflict with humans. However, large carnivores are valuable for ecological, cultural, and ethical reasons. Carnivore management can take a wide variety of forms, including translocation, sterilization, livestock compensation programs, regulated hunting, improved livestock husbandry practices, and zoning, among others. The objective of this thesis was to conduct a comparative analysis of examples of zoning from around the world to examine whether it is an effective carnivore management strategy.
Analysis of twelve case studies showed that …
Search For Novel Molecular Species Formed By Cold Rydberg Atoms In A Magneto-Optical Trap, Alexander Gill
Search For Novel Molecular Species Formed By Cold Rydberg Atoms In A Magneto-Optical Trap, Alexander Gill
Honors Theses
This describes a search for novel ultra-long-range molecular resonances between rubidium Rydberg atoms in a magneto-optical trap (MOT). We use the technique of photoassociative spectroscopy by directly scanning the wavelength of our Rydberg excitation laser about a 5p3/2 - 90p3/2 transition in a weak electric field and by scanning mm-waves about a 39sl/2 - 39p3/2 transition. The results of both of these surveys are inconclusive.
Preparation Of C2 Symmetric Transition Metal Complexes As Potential Chiral Catalysts, Lauren Jean Carlson
Preparation Of C2 Symmetric Transition Metal Complexes As Potential Chiral Catalysts, Lauren Jean Carlson
Honors Theses
Catalytic asymmetric synthesis is of great importance to the industrial production of biologically active substances such as pharmaceuticals, flavoring and sweetening agents, and insecticides. A special class of C2 symmetric transition chiral metal complexes has proven very useful in catalytic asymmetric synthesis.