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Missouri University of Science and Technology

2011

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Articles 61 - 90 of 131

Full-Text Articles in Physical Sciences and Mathematics

Part-I Characterization Of Phorbol Ester; The Predominant Toxic Component Of Jathropha Curcas And Development Of An Efficient Process For The Detoxification Of Jathropha Curcas Meal Part-Ii Quantification Of 2-Hydroxy-4-(Methylthio) Butanoic Acid And Pantothenic Acid In Bovine Serum And Sea Water Matrices, Balaji Viswanathan Jan 2011

Part-I Characterization Of Phorbol Ester; The Predominant Toxic Component Of Jathropha Curcas And Development Of An Efficient Process For The Detoxification Of Jathropha Curcas Meal Part-Ii Quantification Of 2-Hydroxy-4-(Methylthio) Butanoic Acid And Pantothenic Acid In Bovine Serum And Sea Water Matrices, Balaji Viswanathan

Doctoral Dissertations

"Jatropha curcas is has often been touted as the most sustainable biofuel source. Jatropha curcas is a drought resistant perennial plant belonging to the Euphorbiaceae family. Interest in this plant as a biofuel source is related to high lipid (triglyceride) content of its seeds. However, economics of jatropha as a biofuel source has been marred by the toxicity of the oil and its protein rich meal. As a result of high toxicity the protein rich meal is used only as a very low or no economic value organic fertilizer. Economic return from jatropha can be dramatically enhanced through development of …


Absorbing State Transitions In Clean And Disordered Lattice Models, Man Young Lee Jan 2011

Absorbing State Transitions In Clean And Disordered Lattice Models, Man Young Lee

Doctoral Dissertations

"Nonequilibrium systems can undergo continuous phase transitions between different steady states. These transitions are characterized by collective fluctuations over large distances and long times similar to the behavior of equilibrium critical points. They also can be divided into different universality classes according to their critical behavior.

This dissertation considers two types of nonequilibrium transitions. First study concerns absorbing state transitions on a randomly diluted lattice. Second study deals with nonequilibrium models with several absorbing states. We investigate two specific nonequilibrium lattice models, i.e., the contact process and the generalized contact process by means of both theoretical and computational approaches.

In …


Multiple Differential Study Of Fragmentation Processes In 75 Kev Proton-Molecular Hydrogen Collisions, Kisra Nayomal Egodapitiya Jan 2011

Multiple Differential Study Of Fragmentation Processes In 75 Kev Proton-Molecular Hydrogen Collisions, Kisra Nayomal Egodapitiya

Doctoral Dissertations

"Double Differential Cross Sections (DDCS) were measured for single ionization of H₂ by 75 keV proton (p) impact as a function of the projectile scattering angle (θp) for a fixed energy loss (ΔE) for two different target-collimating slit distances, which determined the width of the projectile wave packet (Δx). In one case Δx was larger than the inter-nuclear separation of the H₂ molecule (coherent projectile beam), while for the other case it was much smaller than the inter-nuclear separation (incoherent projectile beam). A Young type interference pattern was observed in the coherent data, but this was not present in the …


Conference Marketing Research For Rolla, Missouri Chamber Of Commerce, Rebecca Mcnally, Bonnie Bachman Jan 2011

Conference Marketing Research For Rolla, Missouri Chamber Of Commerce, Rebecca Mcnally, Bonnie Bachman

Business and Information Technology Faculty Research & Creative Works

This paper is used to give recommendations to the Chamber of Commerce in Rolla, Missouri to help them to better attract conferences and events. A survey given to event planners was the main method used for analyzing what Rolla needs to change to gain more of a name as a conference destination. Although this paper is specific to Rolla, Missouri, the methods used can be imitated for any rural town wishing to attract more conferences.


Applied Palynology: Multidisciplinary Case Studies From Egypt, Gulf Of Mexico And Usa, Mohamed K. Zobaa Jan 2011

Applied Palynology: Multidisciplinary Case Studies From Egypt, Gulf Of Mexico And Usa, Mohamed K. Zobaa

Doctoral Dissertations

"Various applications of palynology have been used to study case studies from four different parts of the world, namely northern Egypt, offshore Gulf of Mexico, eastern Tennessee (USA), and New Orleans, Louisiana (USA). In these case studies, palynomorphs (spores, pollen, dinoflagellate cysts, and algae) have been utilized to define zones of hydrocarbon potential, reconstruct paleoenvironmental and paleoclimatic conditions, constrain the ages of the studied rock sequences, and express its potential as a replacement proxy for some expensive organic geochemical analyses. The ability to detect past hurricane activities and their associated damage to the geologic record is here presented as a …


Mutation Of The Hof1 Pest Domain Affects Cytokinesis In Budding Yeast, Katherine E. Stockstill Jan 2011

Mutation Of The Hof1 Pest Domain Affects Cytokinesis In Budding Yeast, Katherine E. Stockstill

Masters Theses

"Cytokinesis is the division of a cell into two daughter cells. Cytokinesis failure results in polyploidy, which may contribute to tumorigenesis or cause cell death. The Saccharomyces cerevisiae protein Hof1, which is required for efficient cytokinesis, is phosphorylated during mitosis. The hypothesis that MEN (mitotic exit network) dependent phosphorylation regulates Hof1 degradation, triggering completion of cytokinesis was tested. Hof1 contains a PEST sequence, which is rich in proline, glutamic acid, serine, and threonine, and is believed to be involved in protein degradation. To test the hypothesis, we created two non-phosphorylatable mutants of the Hof1 PEST domain tagged with GFP. The …


Pervasive Innovation: Taking Innovation Throughout The Organization, Bonnie Bachman, Stephen O. Bozzone Jan 2011

Pervasive Innovation: Taking Innovation Throughout The Organization, Bonnie Bachman, Stephen O. Bozzone

Business and Information Technology Faculty Research & Creative Works

One of the fundamental tenets of management is that human capital can provide an essential competitive advantage for a business. Pervasive innovation (PI) is a process that blends strategy, structure, process, and culture to elevate product development to new heights and can provide a critical advantage. PI also encompasses new paradigms, practices, methods, and applications that support an environment of creativity and innovation that cuts across organization boundaries, both internal and external boundaries. Pervasive innovation guides the team through the ideation stage to implementation by leveraging the greater collective knowledge of the entire organization. This collaborative approach ensures that the …


Evaluating The Effectiveness Of Multi-Spectral Remote Sensing Data For Lithological Mapping In Arid Regions: A Quantitative Approach With Examples From The Makkah Neoproterozoic Region, Saudi Arabia, Nawwaf Awad Al Muntshry Jan 2011

Evaluating The Effectiveness Of Multi-Spectral Remote Sensing Data For Lithological Mapping In Arid Regions: A Quantitative Approach With Examples From The Makkah Neoproterozoic Region, Saudi Arabia, Nawwaf Awad Al Muntshry

Masters Theses

"This work quantitatively evaluates the effectiveness of multi-spectral remote sensing data for geological mapping in arid regions. For this, Landsat Thematic Mapper (TM) data covering part of the Neoproterozoic Arabian Shield around the Makkah region in Saudi Arabia are used. The Makkah region is dominated by a variety of layered and intrusive rocks covered by unconsolidated sediments. The Landsat TM data have six spectral bands in the visible and near infrared (VNIR) and shortwave infrared (SWIR) with thirty meters spatial resolution.

The Optimum Index Factor (OIF) has been computed to determine the best Red-Green-Blue (RGB) band combination emerging from the …


Epitaxial Electrodeposition Of Metal Oxide Films And Superlattices Which Exhibit Resistance Switching, Rakesh V. Gudavarthy Jan 2011

Epitaxial Electrodeposition Of Metal Oxide Films And Superlattices Which Exhibit Resistance Switching, Rakesh V. Gudavarthy

Doctoral Dissertations

"This dissertation presents an investigation of the electrodeposition of metal oxide films and superlattices on conducting polycrystalline and single crystal substrates. In the first part of the study, electrodeposition of magnetite (Fe₃O₄) films and superlattices in the magnetite/zinc ferrite system which exhibit resistance switching is studied. Paper I reports the electrodeposition of superlattices in the magnetite/zinc ferrite system and shows that only superlattices exhibit multistate resistance switching. In paper II, simple polycrystalline magnetite films electrodeposited on stainless steel crystals exhibit multistate resistance switching which can be tuned by controlling the composition of the films. Paper II describes the epitaxial electrodeposition …


Quantum Phase Transitions In The Presence Of Disorder And Dissipation, Chetan Kotabage Jan 2011

Quantum Phase Transitions In The Presence Of Disorder And Dissipation, Chetan Kotabage

Doctoral Dissertations

"A quantum phase transition is a phase transition at absolute zero occurring under variations in an external non-thermal parameter such as magnetic field or pressure. Quantum phase transitions are one among the important topics currently investigated in condensed matter physics. They are observed in various systems, e.g., in the ferromagnetic-paramagnetic phase transition in LiHoF₄ or in the superconductor-metal phase transition in nanowires.

A particular class of quantum phase transitions, which is phase transitions in the presence of disorder and dissipation, is investigated here. An example of this class is the ferromagnetic-paramagnetic phase transition in Ni₁₋ₓVₓ or CePd1-xRhₓ caused …


Quantum Electrodynamics And Fundamental Constants, Benedikt J. Wundt Jan 2011

Quantum Electrodynamics And Fundamental Constants, Benedikt J. Wundt

Doctoral Dissertations

"The unprecedented precision achieved both in the experimental measurements as well as in the theoretical description of atomic bound states make them an ideal study object for fundamental physics and the determination of fundamental constants. This requires a careful study of the effects from quantum electrodynamics (QED) on the interaction between the electron and the nucleus.

The two theoretical approaches for the evaluation of QED corrections are presented and discussed. Due to the presence of two energy scales from the binding potential and the radiation field, an overlapping parameter has to be used in both the approaches in order to …


Ceeme: Compensating Events Based Execution Monitoring Enforcement For Cyber-Physical Systems, Thoshitha T. Gamage Jan 2011

Ceeme: Compensating Events Based Execution Monitoring Enforcement For Cyber-Physical Systems, Thoshitha T. Gamage

Doctoral Dissertations

"Fundamentally, inherently observable events in Cyber-Physical Systems with tight coupling between cyber and physical components can result in a confidentiality violation. By observing how the physical elements react to cyber commands, adversaries can identify critical links in the system and force the cyber control algorithm to make erroneous decisions. Thus, there is a propensity for a breach in confidentiality leading to further attacks on availability or integrity. Due to the highly integrated nature of Cyber-Physical Systems, it is also extremely difficult to map the system semantics into a security framework under existing security models. The far-reaching objective of this research …


Minimal And Near Minimal Congruence Lattice Representations Of Finite Lattices By Finite Algebras On Sets Of Integers, Roger Lee Bunn Jan 2011

Minimal And Near Minimal Congruence Lattice Representations Of Finite Lattices By Finite Algebras On Sets Of Integers, Roger Lee Bunn

Doctoral Dissertations

"We give finite congruence lattice representations of some finite distributive, modular and nonmodular lattices by means of finite algebras on sets of integers. These representations are minimal or near minimal as determined by ρ, a mapping from the class R of finitely representable lattices into the natural numbers N"--Abstract, page iii.


Energy Auditing Proposal, Paul Parham, Bonnie Bachman Jan 2011

Energy Auditing Proposal, Paul Parham, Bonnie Bachman

Business and Information Technology Faculty Research & Creative Works

Executive Summary 1.1 Objectives Develop a business case for an energy audit software application that can be used on portable devices such as the iPad and reduce the time needed to complete an audit report by 50%.


Interfacial Effects On Dielectric Properties Of Polymer-Particle Nanocomposites, Sasidhar Siddabattuni Jan 2011

Interfacial Effects On Dielectric Properties Of Polymer-Particle Nanocomposites, Sasidhar Siddabattuni

Doctoral Dissertations

"Dielectric materials that are capable of efficiently storing large amounts of electrical energy are desirable for many electronic and power devices. Since the electrical energy density in a dielectric material is limited to εV/2, where ε is the dielectric permittivity of the material and Vb is the breakdown strength, increased permittivity and breakdown strength are required for large energy storage density. Interfacial effects can influence the dielectric properties, especially dielectric breakdown resistance in polymer-particle nanocomposites. Several functional organophosphates were used to modify the surface of titania and barium titanate nanofiller particles in order to achieve covalent interface …


A Geological And Geophysical Study Of The Tendaho Graben In The Afar Depression, Ethiopia: Insights Into Transitional Continental Rifting, David Lee Bridges Jan 2011

A Geological And Geophysical Study Of The Tendaho Graben In The Afar Depression, Ethiopia: Insights Into Transitional Continental Rifting, David Lee Bridges

Doctoral Dissertations

"A detailed magnetic and gravity study across the Tendaho Graben (the Red Sea propagator within the Afar Depression, Ethiopia) revealed features that can best be interpreted as a continental rift undergoing oceanization. This NW-trending extensional structure is ~50 km wide and it is confined within well-developed NW-trending boarder faults that deform the 2 km thick and ~ 2 Ma basaltic flows of the Afar Stratoids. The age of the basaltic flows becomes progressively younger inward from the boarder faults until it reaches ~30,000 years close to the rift axis. The central part of the Tendaho Graben is characterized by a …


Development Of A Versatile Man-Portable Obscurant Aerosol Generator: Characterization Of Aerosols In Laboratory And Field Environments, Robert William Schaub Jan 2011

Development Of A Versatile Man-Portable Obscurant Aerosol Generator: Characterization Of Aerosols In Laboratory And Field Environments, Robert William Schaub

Doctoral Dissertations

"The objective of research presented in this dissertation was to develop a readily deployable and environmentally benign obscurant system operating with a single liquid for the visible and near infrared regions. To achieve this objective, research efforts were directed in two areas: i. Evaluating suitable biogenic oils to replace the United States Army's "Fog Oil" as the obscurant fluid. ii. Design, fabrication and validation of a prototype man-portable / vehicle mountable modular obscurant aerosol generator. Petroleum middle distillate - "Fog Oil" has been the material of choice for wide area obscuration for several decades. Large quantities (thousands gallons) of the …


Investigation Of Occurrence, Elimination And Degradation Of Pharmaceutical And Personal Care Products In Drinking Water Using Liquid Chromatography-Tandem Mass Spectrometry, Chuan Wang Jan 2011

Investigation Of Occurrence, Elimination And Degradation Of Pharmaceutical And Personal Care Products In Drinking Water Using Liquid Chromatography-Tandem Mass Spectrometry, Chuan Wang

Doctoral Dissertations

"Pharmaceutical and personal care products have benefited humans and animals around the world. However, their presence in natural and treated water system as emerging contaminates may have potentially adverse effects on the aquatic environment and cause development of bacterial resistance. In this research project, a comprehensive liquid chromatography tandem mass spectrometry method has been developed and validated for the analysis of sixteen pharmaceutical compounds using solid phase extraction. Treated and untreated water samples collected across Missouri from water treatment facilities were analyzed to access the distribution of sixteen pharmaceutical compounds in both winter and summer seasons. The results of the …


Aerogels And Films Through Free Radical Polymerization, Anand G. Sadekar Jan 2011

Aerogels And Films Through Free Radical Polymerization, Anand G. Sadekar

Doctoral Dissertations

"Aerogels are porous lightweight materials, unique among all solids in terms of low density, low thermal conductivity, low dielectric constants and high acoustic attenuation. The penalty for those exceptional properties is fragility. That issue has been addressed by bridging covalently (crosslinking) the elementary nanoscopic building blocks of silica aerogels with polymers. To streamline the crosslinking process we synthesized a bidentate free radical initiator (Si-AIBN) that gets attached on the skeletal nanoparticles and induces crosslinking by surface initiated polymerization (SIP). Here, we extend the scope of Si-AIBN in two directions: (a) we demonstrate extremely adhering, covalently attached polymer coatings on oxidized …


Cross-Layer Design For Network Performance Optimization In Wireless Networks, Xuan Gong Jan 2011

Cross-Layer Design For Network Performance Optimization In Wireless Networks, Xuan Gong

Doctoral Dissertations

"In this dissertation, I use mathematical optimization approach to solve the complex network problems. Paper l and paper 2 first show that ignoring the bandwidth constraint can lead to infeasible routing solutions. A sufficient condition on link bandwidth is proposed that makes a routing solution feasible, and then a mathematical optimization model based on this sufficient condition is provided. Simulation results show that joint optimization models can provide more feasible routing solutions and provide significant improvement on throughput and lifetime. In paper 3 and paper 4, an interference model is proposed and a transmission scheduling scheme is presented to minimize …


Apparent Weekly And Daily Earthquake Periodicities In The Western United States, And Evolution Of Wadi Kubbania In Egypt, Ali Hadi Atef Jan 2011

Apparent Weekly And Daily Earthquake Periodicities In The Western United States, And Evolution Of Wadi Kubbania In Egypt, Ali Hadi Atef

Doctoral Dissertations

"The dissertation consists of two separate sections. The first section is on apparent daily and weekly periodicities in earthquake occurrence in the western United State [sic]. Analysis of Apparent Seismicity Rate (ASR) in the western United States confirmed the existence of prominent spectral peaks with a period of 1 and 7 days. The number of recorded earthquakes on Sundays for the duration of 1963-2008 is about 5% higher than that on weekdays, and, more significantly, there is a 9% increase of ASR in the early morning compared with that in the middle of the days. Significant similarities between the spatial …


Preliminary Model Development Of Metal Complexation Of Polyester Derivatives Of 2,2'-Biimidazole, Shelonda Rena Taylor Finch Jan 2011

Preliminary Model Development Of Metal Complexation Of Polyester Derivatives Of 2,2'-Biimidazole, Shelonda Rena Taylor Finch

Doctoral Dissertations

"The objective of this study was to develop a chemical model for metal ion complex formation by a macroligand system with multi-metal binding sites using 2,2'-biimidazole as the starting molecule of the ligand system. Prior studies in this laboratory guided the selection of diesters and hydroxyethyl derivatives of 2,2'-biimidazole as model monomers. In addition, metal ion complexation studies with 2,2'-biimidazole derivatives were conducted. As a result, crystal structures of 1,1'-di(methylpropionato)-2,2-biimidazole, 2,2'-bis(1H-imidazolium) dinitrate and silver 2,2'-bis(1H-imidazolium) trinitrate, were reported. The crystal structures indicated a dependence upon the binding ability of the protonated 2,2'-biimidazole and counter ions. transesterification of the diesters and …


One Pot Synthesis Of Metal, Carbides And Polymeric Aerogels, Naveen K. Chandrasekaran Jan 2011

One Pot Synthesis Of Metal, Carbides And Polymeric Aerogels, Naveen K. Chandrasekaran

Doctoral Dissertations

"Ultra-low density, three-dimensional assemblies of nanoparticles are referred to as aerogels, and typically are derived from supercritical fluid (SCF) drying of wet-gels. Aerogels are generally fragile materials, but that issue has been addressed successfully by X-aerogels, in which the inorganic nanoparticle framework plays the role of the template for the accumulation of polymer that connects covalently and crosslinks the nanoparticles. The resulting materials can be 300x stronger than the native network, for a nominal increase in density by a factor of 3x. Since the exceptional mechanical properties of X-aerogels are traced to the conformal polymer coating, it was reasonable to …


Crustal Structure And Evolution Beneath The Colorado Plateau And The Southern Basin And Range Province, Lamuail Bashir Jan 2011

Crustal Structure And Evolution Beneath The Colorado Plateau And The Southern Basin And Range Province, Lamuail Bashir

Doctoral Dissertations

"Stacking of about 15,500 P-to-S receiver functions recorded at 72 USArray and other broadband seismic stations placed on the Colorado Plateau and the SBRP in Arizona revealed systematic spatial variations in crustal Vp/Vs, crustal thickness and amplitude of P-to-S converted phases. Our results reveal that the BRP is characterized by a thin crust (28.2 ± 0.5 km), a mean Vp/Vs of 1.761 ± 0.014 and a mean amplitude (R) of P - to - S converted wave (relative to that of the direct P wave) of 0.181 ± 0.014 that are similar to a typical continental crust, consistent with the …


Modeling Hourly Electricity Prices: A Structural Time Series Approach Incorporating Modified Garch Innovations, Edirisinghe Mudiyanselage Asitha Edirisinghe Jan 2011

Modeling Hourly Electricity Prices: A Structural Time Series Approach Incorporating Modified Garch Innovations, Edirisinghe Mudiyanselage Asitha Edirisinghe

Doctoral Dissertations

"The main objective of this research is to develop time series based procedures for modeling day-ahead and real-time hourly electricity prices. Such empirical processes exhibit features that make the direct application of standard time series models infeasible. Four years of hourly day-ahead and real-time electricity price data from the region supplied by the American Electric Power (AEP) company through the PJM Regional Transmission Organization (RTO) and one half years of real-time electricity prices from the MISO RTO are utilized as an empirical basis for developing such procedures. The price data show several features, such as irregular seasonal behavior, weekly and …


First-Principles Studies Of Complex Hydrides For Li-Ion Battery And Hydrogen Storage Applications, Timothy Hudson Mason Jan 2011

First-Principles Studies Of Complex Hydrides For Li-Ion Battery And Hydrogen Storage Applications, Timothy Hudson Mason

Doctoral Dissertations

"We employ density functional theory in a computational study of two energy storage systems.

In the first, we explore the thermodynamic viability of light metal hydrides as a high capacity Li-ion battery negative electrode. Given a set of solid-state and gas-phase reactants, we have determined the phase diagram in the Li-Mg-B-N-H system in the grand canonical ensemble as a function of lithium electrochemical potential. We present computational results for several new conversion reactions with predicted capacities between 2400 and 4000 mAhg⁻¹ that are thermodynamically favorable and that do not involve gas evolution. We provide experimental evidence for the reaction pathway …


Two New Spline-Based Methods And Real Data Applications: High-Resolution Receiver Function Calculations From Teleseismic Broadband Waveforms And High-Accuracy Practical Potential-Field Integral Transformations, Bingzhu Wang Jan 2011

Two New Spline-Based Methods And Real Data Applications: High-Resolution Receiver Function Calculations From Teleseismic Broadband Waveforms And High-Accuracy Practical Potential-Field Integral Transformations, Bingzhu Wang

Doctoral Dissertations

"While receiver function (RF) calculation is fundamentally important and widely used, it is not well solved due to unstable deconvolution. A spline-based RF calculation method was proposed and it is demonstrated that both individual RFs and the stacked RF calculated with the spline method have sharper peaks than those with the water-level spectral division method and the iterative deconvolution method. At the common peaks on the stacked RFs, there are close similarities for all three RF calculation methods. The better calculated RFs with the spline method lead to improved H - K analysis and improved determination of the optimal Moho …


Probability Theory On Time Scales And Applications To Finance And Inequalities, Thomas Matthews Jan 2011

Probability Theory On Time Scales And Applications To Finance And Inequalities, Thomas Matthews

Doctoral Dissertations

"In this dissertation, the recently discovered concept of time scales is applied to probability theory, thus unifying discrete, continuous and many other cases. A short introduction to the theory of time scales is provided. Following this preliminary overview, the moment generating function is derived using a Laplace transformation on time scales. Various unifications of statements and new theorems in statistics are shown. Next, distributions on time scales are defined and their properties are studied. Most of the derived formulas and statements correspond exactly to those from discrete and continuous calculus and extend the applicability to many other cases. Some theorems …


Receiver Function Studies Of Crustal Structure, Composition, And Evolution Beneath The Afar Depression, Ethiopia, Sattam A. Almadani Jan 2011

Receiver Function Studies Of Crustal Structure, Composition, And Evolution Beneath The Afar Depression, Ethiopia, Sattam A. Almadani

Doctoral Dissertations

"The dissertation utilizes a set of sophisticated computer programs developed at the Geophysics group at Missouri S&T to characterize crustal properties beneath the Afar Depression in Ethiopia where extensional tectonics dominates. In this study, measurements of crustal thickness (H), crustal mean Vp/Vs [which is related to Poisson's ratio (Σ)], and the sharpness of the Moho (R) were determined using teleseismic data from 18 broadband seismic sensors that we deployed along a profile of 250 km long with a station spacing of ~ 10 km. The stations had been recording continuously for an entire year from December 2009 until December 2010. …


Enhanced Photorefractivity In A Polymeric Composite Photosensitized With Carbon Nanotubes Grafted To A Photoconductive Polymer, Naveen Kumar Lingam, Sonali Kalghatgi, Jeffrey G. Winiarz Jan 2011

Enhanced Photorefractivity In A Polymeric Composite Photosensitized With Carbon Nanotubes Grafted To A Photoconductive Polymer, Naveen Kumar Lingam, Sonali Kalghatgi, Jeffrey G. Winiarz

Chemistry Faculty Research & Creative Works

We report on the photosensitization of photorefractive (PR) polymeric composites through the inclusion of multiwalled and singlewalled carbon nanotubes (CNTs), respectively, having poly(N -vinyl carbazole) (PVK) grafted to their surfaces. The PR nature of the holographic gratings was confirmed via the asymmetric exchange of energy in a two-beam-coupling (TBC) geometry, yielding TBC gain coefficients approaching 80 cm-1. In addition, in degenerate-four-wave- mixing experiments the prepared composites exhibited diffraction efficiencies as high as 60% and overmodulation voltages as low as ∼40 V/μm. These notable figures of merit indicate that the grafting of the PVK polymer to the various CNTs …