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Full-Text Articles in Physical Sciences and Mathematics

Visualization Of Monitor-Based Executions, Keerthika Koteeswaran Mar 2008

Visualization Of Monitor-Based Executions, Keerthika Koteeswaran

Computer Science and Engineering Theses - Archive

Concurrent programs play a vital role in the world of software engineering. Concurrent programs are used in various fields such as safety critical applications, applications involving advanced graphical user interface, operating system implementation etc. Concurrent programs due to their inherent multi-threaded nature pose a challenge to software engineers not only in coding but also in ensuring data consistency and accuracy. One of the important software constructs used by concurrent programmers to handle critical sections and data synchronization is monitors. A monitor is an encapsulation of shared data, operations on the data and any synchronization required to access the data~\cite{CarTai06:ModMulti}. Monitors …

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Speciation Of Atmospheric Mercury At Two Sites In Northern Nevada, Usa, Seth N. Lyman, Mae Sexauer Gustin Feb 2008

Speciation Of Atmospheric Mercury At Two Sites In Northern Nevada, Usa, Seth N. Lyman, Mae Sexauer Gustin

USU Uintah Basin Faculty Publications

Gaseous elemental mercury (Hg0), reactive gaseous mercury (RGM), and mercury bound to particles (Hgp) were measured during seasonal 1- or 2-week data collection campaigns at two Mercury Deposition Network sites (NV02 and NV99) in northern Nevada, USA. The sites are rural but are located in an area of diverse natural and anthropogenic mercury sources that include undisturbed and mining mercury-disturbed enriched substrates, coal-fired power plants, ore processing facilities, and industrial facilities. Concentrations of Hg0 averaged over all campaigns were 3.0±1.7 ng m−3 at NV02 and 2.5±3.1 ng m−3 at NV99, higher than has been reported for other rural sites. Hg0 …

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Water Quality, Leona K. Hawks, Terry A. Tindall, Howard M. Deer, Bob Lowe, Kevin C. Kesler, Mardell Parrish, Charles Jeffs, Kitt Farrell Jan 2008

Water Quality, Leona K. Hawks, Terry A. Tindall, Howard M. Deer, Bob Lowe, Kevin C. Kesler, Mardell Parrish, Charles Jeffs, Kitt Farrell

University Extension - OCW

This series of videos discusses water usage and the safety of drinking water. The material comes from two University Extension broadcasts.

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Paleoecology Of Early Jurassic Navajo Sandstone Interdune Deposits, Nathan Daniel Wilkens Jan 2008

Paleoecology Of Early Jurassic Navajo Sandstone Interdune Deposits, Nathan Daniel Wilkens

Canyonlands Research Bibliography

The Lower Jurassic Navajo Sandstone represents a desert that covered more than 366,000 square kilometers. Localized interdune deposits commonly occur along the eastern edge of this desert that include carbonates, bioturbated layers, and plant fossils. Previous studies of these deposits focused on specific fossil types or isolated sites. This study involved a comprehensive analysis of the paleoecology of interdune deposits with an integrated approach combining paleontology, sedimentology and geochemistry. The methods used in this study were devised to test specific paleoecological and preservational questions, including water sources and geochemistry, sedimentation mechanisms, fossil identification and paleoecology, taphonomy, and diagenesis. Three hypotheses …

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Increasing Localization Precision In Sensor Networks With Mobile Beacons - A Genetic Path Planning Approach, Awais Iqbal Jan 2008

Increasing Localization Precision In Sensor Networks With Mobile Beacons - A Genetic Path Planning Approach, Awais Iqbal

Computer Science and Engineering Theses - Archive

This work describes a genetic algorithm based approach to approximate an optimal path for a mobile beacon node in a grid of stationary wireless sensors. As the beacon moves over the field of sensors it broadcasts its location. Sensors that are currently in the proximity of the beacon will receive this communication and can then use several of these messages to compute estimates on their locations. An optimal path is defined as a path that will result in the highest overall precision of location estimates among sensors given a maximum path length for the beacon. We assume that sensors are …

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Nonrigid Image Registration By The Deformation Based Grid Generation, Chih-Yao Hsieh Jan 2008

Nonrigid Image Registration By The Deformation Based Grid Generation, Chih-Yao Hsieh

Computer Science and Engineering Dissertations - Archive

A novel nonrigid image registration algorithm is developed using a well-established mathematic work known as deformation based grid generation. The deformation based grid generation is capable to generate a grid free of mesh folding, which is achieved by devising a positive monitor function describing the anticipated grid point density in the computational domain. Based on this method, a novel nonrigid image registration algorithm is successfully developed with many interesting features. First of all, the functional to be optimized during the image registration process consists of only one term — the similarity term. Thus, no regularization functional is required in this …

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Searching And Ranking Xml Data In A Distributed Environment, Weimin He Jan 2008

Searching And Ranking Xml Data In A Distributed Environment, Weimin He

Computer Science and Engineering Dissertations - Archive

Due to the increasing number of independent data providers on the web, there is a growing number of web applications that require searching and querying data sources distributed at different locations over the internet. Since XML is rapidlygaining in popularity as a universal data format for data exchange and integration, locating and ranking distributed XML data on the web are gaining importance in the database community. Most of existing XML indexing techniques combine structure indexes and inverted lists extracted from XML documents to fully evaluate a full-text query against these indexes and return the actual XML fragments of the query …

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Regridding In Nonrigid Image Registration, Ting-Hung Lin Jan 2008

Regridding In Nonrigid Image Registration, Ting-Hung Lin

Computer Science and Engineering Dissertations - Archive

Regridding was first introduced in viscous fluid registration for preventing folding of the transformation and for maintaining the admissible deformation field in large-deformation nonrigid image registration applications. We investigated the application of regridding to leading nonrigid image registration algorithms, including elastic, fluid, diffusion, curvature, and demons algorithms, and compared the performance and accuracy in each case.We also introduce a grid repairing mechanism based on the adaptive grid-generation method to prevent the transformation from folding. The grid repairing method can be used in conjunction with the proposed regridding scheme to set bounds on the Jacobian determinant of the transformation. We showed …

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Computational Analysis Of Structure And Function Of Genomic Sequences, Abanish Singh Jan 2008

Computational Analysis Of Structure And Function Of Genomic Sequences, Abanish Singh

Computer Science and Engineering Dissertations - Archive

The genetic code consists of long chains of deoxyribonucleic acid (DNA) present in every cell of a living organism. These chains contain both functional and non-functional DNA sequences, and their proportion in the mix varies widely along the tree of life. Generally, more complex organisms tend to feature large amounts of "junk" DNA, whose importance is still subject of a debate in the scientific circles. The functional sequences include coding sequences (genes) and various types of signals, mostly, but not exclusively, controlling the regulation of coding sequences, i.e. activating and deactivating the expression of genes, during the developmental stage, in …

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Plasma Surface Modifications For Biomedical And Electrical Applications, Dhiman Bhattacharyya Jan 2008

Plasma Surface Modifications For Biomedical And Electrical Applications, Dhiman Bhattacharyya

Chemistry & Biochemistry Dissertations - Archive

The focus of this work centers on molecular structuring of surfaces. The surface modifications were achieved using plasma polymerization technology, specifically variable duty cycle pulsed plasmas. The results obtained demonstrate that both exacting film chemistry and film thickness control were achieved during deposition of thin polymeric films on selected substrates. The following achievements are detailed in this thesis:* Identification of a new class of volatile monomers which can be successfully used to synthesize thermoresponsive hydrogel films. A unique aspect of this work is that the lower critical solution temperatures of these gels can be controllably varied by simple adjustment of …

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Cytotoxicity Studies On Metallo-Salens And Their Applications In Gene Delivery, Getachew Abebe Woldemariam Jan 2008

Cytotoxicity Studies On Metallo-Salens And Their Applications In Gene Delivery, Getachew Abebe Woldemariam

Chemistry & Biochemistry Dissertations - Archive

Most of biological catalysts including nucleases are made of active metal centers. Metal complexes that are able to interact with DNA and RNA mimicking these natural nucleases will be valuable as therapeutic agents that target nucleic acids. Metal complexes have been used for very long time to treat different kinds of illnesses including cancer. Platinum based compounds are among the most widely used anticancer agents in clinical use. The first chapter of this dissertation highlights the roles of metal ions and their complexes with regard to biochemical activities, as enzyme inhibitors, anticancer agents and metallo-nucleases. Moreover, we will discuss the …

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Development And Application Of New Mass Spectrometry-Based Proteomics Technologies To Post-Translational Modifications, Yue Chen Jan 2008

Development And Application Of New Mass Spectrometry-Based Proteomics Technologies To Post-Translational Modifications, Yue Chen

Chemistry & Biochemistry Dissertations - Archive

Post-translational modifications (PTMs) represent one of the major cellular mechanisms to diversify the limited number of proteins coded by genome. They provide dynamic regulation of protein functions and the means to fine-tune protein functions in response to the changing cellular environment and physiological conditions. Despite their crucial roles in cellular functions, efficient and sensitive analysis of PTMs remains a daunting analytical challenge. Traditional chemical approaches to characterize PTMs are labor-intensive and time-consuming, often with low sensitivity and specificity. Over the past ten years, biological mass spectrometry has emerged as an indispensable tool to identify and characterize PTMs. Mass spectrometry-based proteomic …

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A Study On The B Family Of Shallow Water Wave Equations, Snehanhsu Saha Jan 2008

A Study On The B Family Of Shallow Water Wave Equations, Snehanhsu Saha

Mathematics Dissertations - Archive

In this dissertation we study b family of shallow water wave equations which include classical Korteweg-de Vries, Camassa-Holm and Degasperis-Procesi equations. We first establish the models of the Camassa-Holm and Degasperis-Procesi equations, deriving them from the shallow waterwave argument and then compare a large class of properties relating to the two equations. Then we consider the b family equation as the parent equation and derive the above mentioned two equations as special cases of the b-family as well as the classical KdV equation.Next we establish results of local well-posedness using Kato's semigroup theory,global existence and blow up solutions under certain …

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Helmholtz's Theorem Based Parametric Non-Rigid Image Registration, Hsi-Yue S. Hsiao Jan 2008

Helmholtz's Theorem Based Parametric Non-Rigid Image Registration, Hsi-Yue S. Hsiao

Computer Science and Engineering Dissertations - Archive

Helmholtz's theorem states that, with suitable boundary condition, a vector field is completely determined if both of its divergence and curl are specified everywhere. Based on this, we developed a new parametric non-rigid image registration algorithm. Instead of the displacements of regular control grid points, the curl and divergence at each grid point are employed as the parameters. This leads to a very simple mathematical model - two Poisson equations in 2-D or three Poisson equations in 3-D which will be used to solve for the displacement field. The similarity measure is sum of squared difference. And multi-resolution is applied …

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Optical And Structural Properties Of Zinc Based Nanoparticles Depend On Temperature And Molar Concentration, Alfonso Juan Hinojosa Jan 2008

Optical And Structural Properties Of Zinc Based Nanoparticles Depend On Temperature And Molar Concentration, Alfonso Juan Hinojosa

Physics Theses - Archive

Zinc based nanoparticles have great potential for use in radiation detection as well as uses in solid state lighting. In this thesis, we report the synthesis of ZnO: Eu3+ with the use of solid state diffusion at temperatures between 600 C and 700 C. We found that the emission of the nanoparticles depends particularly on the synthesis temperature as well as the molar concentration. The emission of the samples can be tuned to either the wavelengths of 495 nm and 611 nm. The formation of ZnO: Eu3+ has been identified with the use the Transmission Electron Microscope (TEM). The TEM …

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A Particle Filter Based Framework For Indoor Wireless Localization Using Custom Ieee 802.15.4 Nodes, Vijay Vasant Dixit Jan 2008

A Particle Filter Based Framework For Indoor Wireless Localization Using Custom Ieee 802.15.4 Nodes, Vijay Vasant Dixit

Computer Science and Engineering Theses - Archive

Locating people and objects as soon as possible and fair amount of precision has always been an important part of any organization or industry, especially in manufacturing, healthcare, and logistics. Systems that now have the ability to locate objects or people are called Real Time Location Systems (RTLS). They typically use small low-power transmitters called tags attached to assets (or worn by people) as well as sets of readers that map the location of these tags. Systems that map the longitude and attitude of an object are geo-location systems and generally use GPS for location mapping. Systems that map a …

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Dynacet: A Minimum-Effort Driven Dynamic Faceted Search System Over Structured Databases, Haidong Wang Jan 2008

Dynacet: A Minimum-Effort Driven Dynamic Faceted Search System Over Structured Databases, Haidong Wang

Computer Science and Engineering Theses - Archive

In this thesis, we propose minimum-effort driven navigational techniques for enterprise database systems based on the faceted search paradigm. Our proposed techniques dynamically suggest facets for drilling down into the database such that the cost of navigation is minimized. At every step, the system asks the user a question or a set of questions on different facets and depending on the user response, dynamically fetches the next most promising set of facets, and the process repeats. Facets are selected based on their ability to rapidly drill down to the most promising tuples, as well as on the ability of the …

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Modeling And Simulation Of A General Motors Conveyor System Using A Custom Decision Optimizer, Mirza Mohammad Lutfe Elahi Jan 2008

Modeling And Simulation Of A General Motors Conveyor System Using A Custom Decision Optimizer, Mirza Mohammad Lutfe Elahi

Computer Science and Engineering Theses - Archive

The temporal behavior of conveyor systems can be modeled using discrete event (DE) simulations. DE modeling provides a quick and cost effective method for analyzing complex problems as different scenarios can be tested rapidly without affecting the day to day activities of production systems. A simulation model coupled with decision optimization on routing choices enables the evaluation of different decision strategies.In the General Motors paint shop at Arlington, Texas, the complex conveyor system moving cars to the paint booths has been observed to mix up same color batches of cars coming from the body shop. At the paint booth, every …

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Use Of Wireless Signal Characteristics For Mobile Robotics Localization And Access Point Mapping, Joshua Davies Jan 2008

Use Of Wireless Signal Characteristics For Mobile Robotics Localization And Access Point Mapping, Joshua Davies

Computer Science and Engineering Theses - Archive

Mobile robotics is an interesting and challenging emerging field in computer science.To properly achieve true autonomy, a robot must be able to determine where it is in relationshipto a global frame of reference and it must be able to do so with a minimum of interaction fromhuman operators and impose as few constraints on its surroundings as possible. The uncertainnature of mobility and perception requires that advanced probabilistic inference techniques beapplied to minimize error. This work examines the applicability of radio-frequency signals to the mobile robotlocalization problem to localize quickly over a wide area. Particle filtering techniques areemployed to adjust …

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Towards An Implementation Of Avoip: Anonymous Voice-Over-Ip, Bikas Raj Gurung Jan 2008

Towards An Implementation Of Avoip: Anonymous Voice-Over-Ip, Bikas Raj Gurung

Computer Science and Engineering Theses - Archive

Voice over IP (VoIP) is one of the fastest growing telecommunicaiton market today. However with great popularity comes greater security risk. When we communicate over the Internet we expose our identity to all the prying eyes, even if we do not want to. Even though VoIP data can be secured by using encryption, sometimes the relationships between users can be sensitive. To provide stronger privacy for these users, we propose anonymous VoIP (aVoIP) - a means to secure user privacy in VoIP. The biggest challenge in introducing anonymity to VoIP system is in providing acceptable Quality of Service (QoS). Users …

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Temporal Potential Function Approach For Path Planning In Dynamic Environments, Vamsikrishna Gopikrishna Jan 2008

Temporal Potential Function Approach For Path Planning In Dynamic Environments, Vamsikrishna Gopikrishna

Computer Science and Engineering Theses - Archive

A Dynamic environment is one in which either the obstacles or the goal or both are in motion. In most of the current research, robots attempting to navigate in dynamic environments use reactive systems. Although reactive systems have the advantage of fast execution and low overheads, the tradeoff is in performance in terms of the path optimality. Often, the robot ends up tracking the goal, thus following the path taken by the goal, and deviates from this strategy only to avoid a collision with an obstacle it may encounter. In a path planner, the path from the start to the …

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Adapting Harmonic Function Path Planning: To Reflect User Motion Preferences, Giles John D'Silva Jan 2008

Adapting Harmonic Function Path Planning: To Reflect User Motion Preferences, Giles John D'Silva

Computer Science and Engineering Theses - Archive

Every human in the real world has a unique motion preference while moving to achieve a given task. These preferences could be expressed by moving in a straight line, following the wall along a corridor, avoiding sharp turns, preferring hard flat surfaces over damp uneven surfaces, choosing the shortest path to the goal or by giving a high priority towards safety by maintaining a definite distance from obstacles. To automatically incorporate user preferences into motion planning we could extract the trajectories taken by the user to achieve a task in a given local vironment and attempt to use them in …

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Spectroscopy Is Applied Quantum Mechanics. Part 2: The Quantum Revolution, David W. Ball Jan 2008

Spectroscopy Is Applied Quantum Mechanics. Part 2: The Quantum Revolution, David W. Ball

Chemistry Faculty Publications

The article presents several theories relative to the nature of matter. The quantum theory of German theoretical physicist Max Planck proposes that the energy of a vibrating atom was related to its frequency. Albert Einstein's quantum theory of light hypothesizes that light itself had an energy that was directly proportional to its frequency. Danish physicist Niels Bohr develops an equation that could help explain the lines that appeared in the spectrum of the hydrogen atom.

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Investigation Of Redox-Active Ruthenium(Ii) Polypyridyl Complexes As Potential Anti-Cancer Drugs, Abhishek Yadav Jan 2008

Investigation Of Redox-Active Ruthenium(Ii) Polypyridyl Complexes As Potential Anti-Cancer Drugs, Abhishek Yadav

Chemistry & Biochemistry Dissertations - Archive

Stereospecific binding of ruthenium metallointercalators with DNA is of particular interest because of the potential for improved targeting of specific sites in DNA. The present studies are focused on new metallointercalator, ruthenium (II) polypyridyl complex [(phen) 2 Ru(tatpp)(phen) 2 ]Cl 4 , [P p ] 4+ , and it's structural analog [Ru(phen) 2 (tatpp)]Cl 2 , [MP p ] 2+ ; the latter contains a redox active bridging ligand tatpp (where tatpp = 9,11,20,22-tetraazatetrapyrido[3,2-a:2',3'-c:3'',2''-l:2''',3'''-n]-pentacene and phen = 1,10-phenanthroline). Complex [P p ] 4+ exists as a mixture of ΔΔ-, ΔΔ- and ΔΔ- stereisomers whereas [MP p ] 2+ exists as …

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A Faculty Workshop On Student Assessment, Iris M. Totten, Kirsten Nicolaysen, Sheryl Hodge, Mary S. Hubbard Jan 2008

A Faculty Workshop On Student Assessment, Iris M. Totten, Kirsten Nicolaysen, Sheryl Hodge, Mary S. Hubbard

Geosciences Faculty Publications

A faculty workshop was conducted that showcased assessment activities that could be incorporated into undergraduate and graduate geology courses. Fourteen different types of student assessment were presented. Workshop participants were asked to respond to questions about their familiarity and use of each type before and immediately following the workshop. In addition, they were asked to indicate how likely they would be to incorporate each type of assessment in their student grading practices in the future. Results suggest relatively high familiarity and use of the more traditional types of assessments (e.g., instructor- and commercially-produced pencil and paper exams, group projects, and …

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Synthesis And Study Of Fluorinated Thiophenes, Bithiophenes And Trithiophenes: Models For The Polymeric Material, Nashaat Turkman Jan 2008

Synthesis And Study Of Fluorinated Thiophenes, Bithiophenes And Trithiophenes: Models For The Polymeric Material, Nashaat Turkman

Chemistry & Biochemistry Dissertations - Archive

3-Fluorothiophene is a small molecule and the known syntheses for this molecule are far from being straight forward and suffer from many drawbacks such as low yield, long synthetic procedures and the use of expensive or dangerous fluorinating agents. The synthesis of 3-fluorothiophene was accomplished in four steps and 49% overall yield by a very convenient method. 2,5-Dibromo-3-fluorothiophene was prepared in essentially one step synthesis involving a decarboxylation-bromination reaction. Both 3-fluorothiophene and 2,5-dibromo-3-fluorothiophene are potential monomers for a wide variety of fluorinated polythiophenes. Fluoroalkyl thiophene monomers, dimers and trimers were prepared. 3-Heptanoylthiophene is a key intermediate in the synthesis of …

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Fabrication Of Superparamagnetic And Ferromagnetic Nanoparticles, Narayan Poudyal Jan 2008

Fabrication Of Superparamagnetic And Ferromagnetic Nanoparticles, Narayan Poudyal

Physics Dissertations - Archive

Monodisperse magnetic nanoparticles with controlled size and geometry have drawn great attention in the last decade for fundamental scientific studies and for their potential applications in advanced materials and devices such as ultra high-density magnetic recording media, exchange-coupled nanocomposite magnets, biomedicine and nanodevices. This dissertation focuses on the fabrication and characterization of superparmagnetic and ferromagnetic nanoparticles of hard magnetic materials (FePt, SmCo5, Sm2Co17 and Nd2Fe14B) and soft magnetic materials (CoFe2O4, NiFe2O4 and FeCo). Novel preparation techniques including salt-matrix annealing, surfactant-assisted ball milling and magnetic field milling have been adopted in this study. The FePt nanocrystals with a variety of morphologies …

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A Scan Of Attributes In County Government Structure, Kevin O'Brien, Holly Cooper Whisman, Ryan Foster, Melissa Rowe Jan 2008

A Scan Of Attributes In County Government Structure, Kevin O'Brien, Holly Cooper Whisman, Ryan Foster, Melissa Rowe

All Maxine Goodman Levin School of Urban Affairs Publications

This report discusses the outcome of a national scan of models of effective county leadership and operations that might translate into alternative structures for consideration by the Commission on Cuyahoga County Government Reform. The scan produced a number of alternate county organizational structures that utilized several formats for executive, legislative, and administrative roles.

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Can Silicon Carbide Nanotubes Be Effective Storage Medium For Hydrogen Storage?, Souptik Mukherjee Jan 2008

Can Silicon Carbide Nanotubes Be Effective Storage Medium For Hydrogen Storage?, Souptik Mukherjee

Physics Theses - Archive

A systematic study of molecular hydrogen adsorption on three different atomic configurations of armchair SICNTs has been performed. In the first stage of our study, first principles calculations using both density functional theory (DFT) and hybrid density functional theory (HDFT) as well as the finite cluster approximation have been performed to study the adsorption of molecular hydrogen on three types of armchair (9, 9) silicon carbide nanotubes. The distances of molecular hydrogen from the outer wall of the nanotubes have been optimized manually using the B3LYP and PW91 functionals and results have been compared in detail with published literature results. …

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Ferrimagnetism And Magnetic Entropy Change For Tm/Re Multilayers, Maria Rodica Hossu Jan 2008

Ferrimagnetism And Magnetic Entropy Change For Tm/Re Multilayers, Maria Rodica Hossu

Physics Dissertations - Archive

Multilayers of Co/Tb, Ni/Gd, NiFe/Gd, CoFe/Gd and CoNi/Gd multilayers have been synthesized using dc magnetron sputtering and have been investigated experimentally by SQUID magnetometry. Due to the antiferromagnetic coupling between the transition metal and rare earth layers these systems behave like artificial ferrimagnets, with a minimum in total magnetic moment at compensation temperature. The measurement of magnetic moment (M) as a function of temperature (T) shows that magnetic phase transition occurs at different temperatures during the heating (superheating) and cooling (supercooling) cycles resulting in thermal hysteresis curve for M (T). Magnetic entropy change has been measured for CoFe/Gd and CoNi/Gd …

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