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2009

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Articles 5971 - 6000 of 7616

Full-Text Articles in Physical Sciences and Mathematics

Computational Analysis Of Metabolomic Toxicological Data Derived From Nmr Spectroscopy, Benjamin J. Kelly Jan 2009

Computational Analysis Of Metabolomic Toxicological Data Derived From Nmr Spectroscopy, Benjamin J. Kelly

Browse all Theses and Dissertations

Nuclear magnetic resonance (NMR) spectroscopy is a non-invasive method of acquiring metabolic profiles from biofluids. The most informative metabolomic features, or biomarkers, may provide keys to the early detection of changes within an organism such as those that result from exposure to a toxin. One major difficulty with typical NMR data, whether it come from a toxicological, medical or other source, is that it features a low sample size relative to the number of variables measured. Thus, traditional pattern recognition techniques are not always feasible. The "curse of dimensionality" is an important consideration in selecting appropriate statistical and pattern recognition …


Circulant Weighing Matrices, Alex James Gutman Jan 2009

Circulant Weighing Matrices, Alex James Gutman

Browse all Theses and Dissertations

The existence status of previously open cases of circulant weighing matrices will be established using various techniques. The results fill in 52 missing entries in Strassler's Table of Circulant Weighing Matrices, which considers matrices of order 1 - 200 with weight k less than or equal to 100.


Porosity And Permeability In Ternary Sediment Mixtures, Jason Dennis Esselburn Jan 2009

Porosity And Permeability In Ternary Sediment Mixtures, Jason Dennis Esselburn

Browse all Theses and Dissertations

Porosity and permeability were measured in mixtures of fine, medium, and coarse sand, where the volume fraction of each of the three components was systematically varied. The porosity varies non-linearly with the volume fractions, and can be modeled with a piecewise-linear approach. The permeability also varies non-linearly with the volume fractions. Permeability can be modeled with the Kozeny-Carman equation using a recursive approach for computing the representative grain size from those of the components in the mixture.


Measuring The Permeability Of Open-Framework Gravel, James Thomas Ferreira Jr. Jan 2009

Measuring The Permeability Of Open-Framework Gravel, James Thomas Ferreira Jr.

Browse all Theses and Dissertations

Open-framework gravel has permeability, k, above the measurement range of most conventional constant-head permeameters used in laboratories. Here I addressed the challenge of measuring such high k by using a permeameter long enough that the differences in head across it were on the order of 10-3 m and therefore measurable. I collected data over the range from linear-laminar flow to non-linear, non-Darcian flow. In doing so, I verified that k was measured under Darcian flow. I measured k between 4,000 and 100,000 Darcies among experiments using different sediments.


A Morphometric Analysis Of The Highly Variable Clypeasteroid, Periarchus Lyelli, Lauren Elizabeth Williamson Jan 2009

A Morphometric Analysis Of The Highly Variable Clypeasteroid, Periarchus Lyelli, Lauren Elizabeth Williamson

Browse all Theses and Dissertations

The Late Eocene echinoid, Periarchus lyelli (Conrad, 1834), known for its wide geographic range, high abundance, and specific stratigraphic range, is an ideal example of a guide fossil. However, due to its highly variable test morphology, many have questioned if, in fact, this sand dollar is actually two or three distinct species that have been misclassified. A preliminary study on this subject has been performed on specimens from Mississippi, North Carolina and South Carolina (Williamson, 2006), showing significant separation in test shapes. Continuing previous research, this study analyzes the test shapes of P. lyelli over its entire North American geographic …


Conservation Genetics Of A Near Threatened Freshwater Mussel Species (Lampsilis Cardium) And Improved Prospects For Recovery: How Nuclear And Mitochondrial Dna Analyses Inform Natural History And Conservation, Chad D. Ferguson Jan 2009

Conservation Genetics Of A Near Threatened Freshwater Mussel Species (Lampsilis Cardium) And Improved Prospects For Recovery: How Nuclear And Mitochondrial Dna Analyses Inform Natural History And Conservation, Chad D. Ferguson

Browse all Theses and Dissertations

Freshwater mussels (Bivalvia: Unionidae) are among the most imperiled organisms in North America. While there is an urgent need for effective conservation planning and management of these organisms, important basic biological information is lacking. This research characterizes levels of genetic diversity and population structure in the Near Threatened (IUCN) freshwater mussel Lampsilis cardium in populations from Twin Creek (southwest Ohio), Little Darby and Big Darby Creeks (central Ohio), and Little Muskingum River (eastern Ohio) and assesses the extent to which regional geological events explain population structuring. Data from the congener Lampsilis ovata from Clinch River (Tennessee) are included for comparison. …


A System For Incorporating Time-Based Event-Condition-Action Rules Into Business Databases, Christina Marie Steidle Jan 2009

A System For Incorporating Time-Based Event-Condition-Action Rules Into Business Databases, Christina Marie Steidle

Browse all Theses and Dissertations

Human beings handle time-based events continuously; however the passage of time does not play an active part in most business systems because they are typically driven by interaction from human users or other systems. In order to take an action based upon the passage of time it is necessary to build a framework which will monitor the progression of time and a way to define what events the system should be waiting for. This thesis describes such a system, and shows that the system performs as specified. With this system business users are able to build event-condition-action rules using a …


Quantum Chemical Investigations Of Nucleophilic Aromatic Substitution Reactions And Acid Dissociations Of Aliphatic Carboxylic Acids, David Henry Schory Jan 2009

Quantum Chemical Investigations Of Nucleophilic Aromatic Substitution Reactions And Acid Dissociations Of Aliphatic Carboxylic Acids, David Henry Schory

Browse all Theses and Dissertations

Quantum chemical analysis was used to examine nucleophilic aromatic substitution reactions of fluorinated benzophenones, diphenyl sulfones, and triphenylphosphine oxides. Some experimental results for these compounds were contrary to conventional wisdom, which holds that calculated atomic charges for the aromatic sites and 13C-NMR and 19F-NMR chemical shifts should allow prediction of the preferred sites for aromatic substitution. Density functional theory (B3LYP/6-31+G*//RM1) and semi-empirical (RM1) quantum chemical calculations were employed to study the intermediates in the reaction pathways in order to identify the preferred paths for aromatic substitution. In most cases studied para substitution pathways had the lower energy intermediates …


Design, Fabrication, And Operation Of Two Broadband Force Balance Seismometers, Andrew Weber Jan 2009

Design, Fabrication, And Operation Of Two Broadband Force Balance Seismometers, Andrew Weber

LSU Master's Theses

The measurement of ground motion is important for a wide range of fields. In physics, advanced experiments can involve precise positioning of components. In civil engineering, engineers need to know the characteristics of ground motion to better design large scale structures, and the study of ground motion form distant earth quakes help geologists understand the structure and dynamics of the earth. Each application requires instruments of different specifications. In this thesis I describe the design, fabrication, assembly, and operation of two broad band force balance seismometers and the associated control software. The design, control elements, and methods used in this …


Applying The Isotope Pairing Technique To Evaluate How Water Temperature And Habitat Type Influence Denitrification Estimates In Breton Sound, Louisiana, Peter L. Lenaker Jan 2009

Applying The Isotope Pairing Technique To Evaluate How Water Temperature And Habitat Type Influence Denitrification Estimates In Breton Sound, Louisiana, Peter L. Lenaker

LSU Master's Theses

The upper Breton Sound estuary was hydrologically reconnected to the Mississippi River via the Caernarvon freshwater diversion structure in 1991. The Caernarvon structure can provide controlled freshwater pulses to the upper Breton Sound estuarine ecosystem, replicating historic freshwater pulsed events, although the original authorization was to control salinity isohalines at specific locations in the estuary. However, unlike historic freshwater pulsed events prior to the construction of levees, the current freshwater pulse contains an unprecedented amount of inorganic nitrogen, predominately as nitrate (annual average 71.4 µM NO3-). Denitrification is a microbial process, which can potentially remove excess nitrate entering coastal Louisiana …


Source(S) Of Salinity In The Mississippi River Alluvial Aquifer, Iberville Parish, Louisiana, Stephanie Erin Welch Jan 2009

Source(S) Of Salinity In The Mississippi River Alluvial Aquifer, Iberville Parish, Louisiana, Stephanie Erin Welch

LSU Master's Theses

The Mississippi River Alluvial Aquifer extends from Southern Illinois to the mouth of the Mississippi and is comprised of fluvial sands and gravels of Late Pleistocene age. Several areas of the aquifer in Arkansas, Mississippi, and Louisiana are affected by elevated levels of salinity. One such area occurs in Iberville Parish, LA, where the aquifer is 150-240 m in thickness and is capped by 23-38 m of clay. Recharge of the aquifer from the Mississippi River on the east is fresh, but salinity is high in the western portions of the aquifer and chloride levels are as high as 1,000 …


Development Of Methodology For The Use Of Multi-Bed Sorbent Traps With Gas Chromatography Time Of Flight Mass Spectrometry, Siva Maheswara Reddy Anna Pareddy Jan 2009

Development Of Methodology For The Use Of Multi-Bed Sorbent Traps With Gas Chromatography Time Of Flight Mass Spectrometry, Siva Maheswara Reddy Anna Pareddy

Master's Theses and Doctoral Dissertations

The lipid peroxidation of unsaturated fatty acids in cellular membranes leads to the formation of alkanes, aldehydes, alkanals, alk-2-enals, and hydroxyl alkenals. The free radicals formed during the process of lipid peroxidation can react with and damage cellular components. Lipid peroxidation is known to cause a number of diseases such as cancer, diabetes, and heart disease. Various analytical methods that include spectrometric assays and chromatographic analyses of derivatized products are available for the detection of the lipid peroxidation products.

The development of rapid, non-invasive monitoring of reactions occurring in biological systems, such as cell cultures, is highly desirable, as such …


An Improved Synthesis Of The Hdac Inhibitor Trichostatin A, Joseph Colombo Jan 2009

An Improved Synthesis Of The Hdac Inhibitor Trichostatin A, Joseph Colombo

Master's Theses and Doctoral Dissertations

Histone deacetylase inhibitors (HDIs) have found a wide variety of medicinal uses and are most noted for their specific apoptotic action towards cancer cells. Several hydroxamate HDIs have since been moved on to phase 1 and 2 clinical drug trials, with one having already been approved for treatment of advanced cutaneous T-cell lymphoma. Trichostatin A is one of the most potent known naturally-occurring inhibitors of histone deacetylase. Unfortunately for researchers, the syntheses that have been reported are both long and difficult, which leads to a low overall yield and therefore to a prohibitively expensive product, limiting its medicinal potential. This …


Development Of A Headspace Solid-Phase Microextraction (Hs-Spme) Procedure For The Determination Of Short-Chain Fatty Acids (Scfas) In Activated Sludge By Gc-Fid, Shiyan Cheng Jan 2009

Development Of A Headspace Solid-Phase Microextraction (Hs-Spme) Procedure For The Determination Of Short-Chain Fatty Acids (Scfas) In Activated Sludge By Gc-Fid, Shiyan Cheng

Master's Theses and Doctoral Dissertations

The process of wastewater treatment includes the removal of inorganic solids such as sand and gravel as well as organic materials, phosphorus, and nitrogen. Activated sludge, containing a variety of living organisms, is added into the wastewater treatment system. Short-chain fatty acids (SCFAs), an energy source of the bioorganisms, are produced during activated sludge digestion, and play a significant role in phosphorus and nitrogen removal as well as the removal of organic materials during the process of wastewater treatment. Extensive research has been carried out recently in search of optimized conditions to increase the level of fatty acids in the …


A Fuzzy Hierarchical Decision Model And Its Application In Networking Datacenters And In Infrastructure Acquisitions And Design, Michael Khader Jan 2009

A Fuzzy Hierarchical Decision Model And Its Application In Networking Datacenters And In Infrastructure Acquisitions And Design, Michael Khader

Walden Dissertations and Doctoral Studies

According to several studies, an inordinate number of major business decisions to acquire, design, plan, and implement networking infrastructures fail. A networking infrastructure is a collaborative group of telecommunications systems providing services needed for a firm's operations and business growth. The analytical hierarchy process (AHP) is a well established decision-making process used to analyze decisions related to networking infrastructures. AHP is concerned with decomposing complex decisions into a set of factors and solutions. However, AHP has difficulties in handling uncertainty in decision information. This study addressed the research question of solutions to AHP deficiencies. The solutions were accomplished through the …


Evaluating Earnings Management With Derivatives And The Use Of Accounting Accruals: A Quasi Experimental Approach, Margot S. Geagon Jan 2009

Evaluating Earnings Management With Derivatives And The Use Of Accounting Accruals: A Quasi Experimental Approach, Margot S. Geagon

Walden Dissertations and Doctoral Studies

Most companies listed on the S&P 500 index have reported smoothed earnings since the 1990s inspiring questions from regulators about the accuracy of financial statements. In 1998, the Financial Accounting Standards Board issued SFAS No. 133 (Accounting for Derivative Instruments and Hedging Activities) to establish accounting and reporting standards for derivative instruments. In 2002, the Sarbanes-Oxley Act (SOX) was issued to eradicate earnings management activities and improve transparency in financial reporting. Although many studies have been conducted to evaluate changes in reporting requirements, much less is known about the effectiveness of these regulations on earning smoothing with discretionary accruals (DA) …


Neurotoxin In A Louisiana Estuary: Quantitative Analysis Of Domoic Acid In Gulf Menhaden (Brevoortia Patronus) And Qualitative Modeling Of Links In A Shark Nursery, Ross Del Rio Jan 2009

Neurotoxin In A Louisiana Estuary: Quantitative Analysis Of Domoic Acid In Gulf Menhaden (Brevoortia Patronus) And Qualitative Modeling Of Links In A Shark Nursery, Ross Del Rio

LSU Master's Theses

Harmful algal blooms are an increasing problem for coastal waters world-wide. The diatom genus, Pseudo-nitzschia, is of particular concern in Louisiana, due to the potential for several species to produce the neurotoxin domoic acid (DA). While trophic transfer of DA to consumers has repeatedly occurred along the California coast, little is known about trophic transfer of recently detected DA in the Gulf of Mexico. In this study, the presence of DA in gulf menhaden (Brevoortia patronus) and the potential for trophic transfer to higher order consumers was investigated. In addition, the effects of this transfer and other algal toxins that …


Your Land Is My Land: Exploring Land Policy In Tangerang, Indonesia Using Kingdon's Multiple Streams Model, Milla Budiarto Jan 2009

Your Land Is My Land: Exploring Land Policy In Tangerang, Indonesia Using Kingdon's Multiple Streams Model, Milla Budiarto

LSU Master's Theses

Indonesia is the world’s largest archipelagic country comprised of over 17, 000 islands with more than 300 ethnic groups and more than 250 different ethnic languages spoken. Due to its land mass size and multifaceted culture, land policy in this country has been ineffective and inadequate in addressing some of the land affairs. One of the indicators of effective land policy is land tenure security, where land dispute incidence is a function of it. Given that the government has very minimal guarantee for land tenure security in this nation, land disputes are inevitable and very common. By the end of …


Comparison Of Helical Tomotherapy And Mixed Beam Treatment Plans For Superficial Head And Neck Cancers, Olivier C. Blasi Jan 2009

Comparison Of Helical Tomotherapy And Mixed Beam Treatment Plans For Superficial Head And Neck Cancers, Olivier C. Blasi

LSU Master's Theses

Purpose: To compare helical tomotherapy (HT) with mixed beam therapy (electron and IMRT) plans for superficial parotid gland and nasal cavity tumors. Methods: Mixed beam and HT dose plans were developed for five patients with superficial tumors (planning target volume or PTV < 5.5 cm depth), three with parotid gland tumors and two with nasal cavity tumors. Seven mixed beam plans included a 5 or 7-field photon IMRT plan optimized on top of a single en-face 16 or 20 MeV electron beam dose distribution. The ratio of photon to electron beam weights (at depth R100) were 1:0 (IMRT only), 2:1, 1:1, 1:2, 1:3, 1:4, and 0:1 (electrons only). Planning objectives for HT plans were set as closely as possible to those in the mixed beam plans, and were determined using our clinical planning protocol for head and neck cancers. The resulting dose distribution from each plan was evaluated using dose-volume quantities, tumor control probability (TCP), normal tissue complication probability (NTCP), and a clinical evaluation by a radiation oncologist. Results: In general, the HT plans showed better target coverage and dose homogeneity index (DHI) than the mixed beam plans. For the parotid patients, the DHI improved an average of 0.056 and 0.035 for the nasal cavity patients compared to the mixed beam plan. TCP was comparable in all patients. NTCP for the mixed beam plan was generally lower or comparable to HT with the largest improvements seen in the contralateral parotid, eye, and lens. Also, the mixed beam plans yielded more favorable PTV and normal tissue results for a single shallow uniform PTV using a heavier weighted electron to IMRT ratio (1:3 or 1:4 ratio of electron to IMRT). Conclusions: The study showed that while HT plans had better target coverage and dose homogeneity, the mixed beam plans (electron and IMRT) had comparable tumor control probability and have the potential for improving NTCP for distal normal tissue for superficial uniform PTVs.


Supercritical Fluid Extraction And Analysis Of Plant Oils, Tianchuan Du Jan 2009

Supercritical Fluid Extraction And Analysis Of Plant Oils, Tianchuan Du

LSU Master's Theses

Supercritical fluid extraction (SFE) of oxeye daisy (Chrysanthemum leucanthemum L.) seed, heartwood of Port-Orford cedar (POC) (Chamaecyparis lawsoniana), Alaska yellow cedar (AYC) (Chamaecyparis nootkatensis), and Eastern red cedar (ERC) (Juniperus virginiana L), and Chinese tallow (Sapium sebiferum L. Roxb. ) seed was investigated in this study and compared with other extraction methods. For the oxeye daisy seed extraction, Soxhlet extraction (SE) with hexane, microwave assisted extraction (MAE), and supercritical fluid extraction (SFE) were conducted. The results showed that as the extraction temperature decreased from 100 °C, the extraction rate increased until 30 °C using SFE. With an increase of extraction …


Populations Of Vibrio Vulnificus And Vibrio Parahaemolyticus In Breton Sound And Barataria Bay, Brian William Matherne Jan 2009

Populations Of Vibrio Vulnificus And Vibrio Parahaemolyticus In Breton Sound And Barataria Bay, Brian William Matherne

LSU Master's Theses

Vibrio vulnificus and Vibrio parahaemolyticus are halophilic gram-negative bacteria that are found in warm coastal waters. These two species are the leading cause of fatal shellfish poisoning. The objective of this study was to determine the population dynamics of V. vulnificus and V. parahaemolyticus as impacted by temperature and salinity in Breton Sound and Barataria Bay of Louisiana. Water samples were collected from each water body along s salinity gradient transect monthly from September 2007 through July 2009. Furthermore, from March 2008 through July 2009 sediment and live oyster samples were collected exclusively from the Breton Sound. The population of …


Certification: Implications For Sustainable Forest Management And Timber Export Trade In Ghana, Abraham Baffoe Jan 2009

Certification: Implications For Sustainable Forest Management And Timber Export Trade In Ghana, Abraham Baffoe

LSU Master's Theses

Forestry is a major contributor to the Ghanaian economy and has the potential to increase its contribution if a number of challenges are overcome. Over the past 15 years, Ghana has modified its forest policies, laws, and regulations, but still faces serious challenges with illegal logging and unsustainable forest management. At the same time, Ghana’s major wood product trading partner, the European Union (EU), is requesting that Ghana, under the Voluntary Partnership Agreement (VPA), ensures that wood products from Ghana to the EU are legally produced. Additionally, several EU wood product importers have requested their suppliers in Ghana to meet …


The Use Of The Online Tutorial And Assessment System, Mathxl, In Teaching Of Algebra I, Darlene Noble Ford Jan 2009

The Use Of The Online Tutorial And Assessment System, Mathxl, In Teaching Of Algebra I, Darlene Noble Ford

LSU Master's Theses

The integration of web based learning tools into the teaching of mathematics holds much promise for engaging middle and high school students. The purpose of this thesis is to report about my experiences regarding the effectiveness of using an online homework, tutorial and assessment system as part of two of the six Algebra I math classes I taught in the 2008-2009 school year at Sherwood Middle Academic Magnet School in East Baton Rouge Parish. Comparing the two sets of classes I found that such online systems offer many potential advantages to educators, such as the ability to provide instantaneous feedback, …


The Effects Of Bait Type, Trap-Soak Duration, And Trap Modification On Harvest Of Red Swamp Crawfish, David C. Hardee Jan 2009

The Effects Of Bait Type, Trap-Soak Duration, And Trap Modification On Harvest Of Red Swamp Crawfish, David C. Hardee

LSU Master's Theses

The effects of bait type, trap-soak duration, and a trap entrance modification were evaluated from February through May 2008 in a 1.29 ha crawfish (red swamp crawfish, Procambarus clarkii) pond in southwest Louisiana. Commercial pyramid traps with three entrance funnels, 1.9-cm square-mesh vinyl-coated welded metal wire, were used. In trial 1, crawfish catch was evaluated in traps baited with Atlantic menhaden (Brevoortia tyrannus), a formulated dry bait, or a menhaden+formulated bait mixture, each at 24-h and 48-h soak durations. In trial 2, the escape of marked crawfish was evaluated in the presence or absence of bait at 24-h and 48-h …


Improved Seismic Isolation For The Laser Interferometer Gravitational Wave Observatory With Hydraulic External Pre-Isolator System, Shyang Wen Jan 2009

Improved Seismic Isolation For The Laser Interferometer Gravitational Wave Observatory With Hydraulic External Pre-Isolator System, Shyang Wen

LSU Doctoral Dissertations

LIGO hosts the world’s most sensitive GW detectors capable of detecting strain of h=10-22 at 100-200Hz. To maximize the amount of useful scientific results LIGO generates, it is necessary to operate the instrument uninterruptedly. However, for ground-based detectors, this is not possible without isolating it from the environmental disturbances, which in most cases is predominated by seismic noise. We examined the recent seismic noise records at LLO and LHO, and found the seismic noise at both sites had decreased from Oct. 1, 2003 to Oct. 1, 2006. No long term trend can be derived from the there-year data studied, however …


Toxicological Monitoring And Protocol Development For Abandoned Pipeline Removal In Louisiana, Forest Christopher Wootten Jan 2009

Toxicological Monitoring And Protocol Development For Abandoned Pipeline Removal In Louisiana, Forest Christopher Wootten

LSU Master's Theses

Oil/Gas extraction have left Louisiana with a legacy of abandoned infrastructure across the State. Presently, the State has developed guidelines for the removal of abandoned vessels and abandoned on shore facilities. No such guidelines exist, however, for the network of abandoned pipelines present throughout the coastal zone of Louisiana. A pipeline removal was simulated in Lake Calcasieu, LA. The site was chosen because of the presence of many abandoned pipelines and previous work done on sight to remove the on shore infrastructure. In addition, the Calcasieu is an industrial water body, with potentially hazardous pollutants sequestered in the sediments of …


The Segal-Bargmann Transform On Inductive Limits Of Compact Symmetric Spaces, Keng Wiboonton Jan 2009

The Segal-Bargmann Transform On Inductive Limits Of Compact Symmetric Spaces, Keng Wiboonton

LSU Doctoral Dissertations

We construct the Segal-Bargmann transform on the direct limit of the Hilbert spaces $\{L^2(M_n)^{K_n}\}_n$ where $\{M_n = U_n/K_n\}_n$ is a propagating sequence of symmetric spaces of compact type with the assumption that $U_n$ is simply connected for each $n$. This map is obtained by taking the direct limit of the Segal-Bargmann tranforms on $L^2(M_n)^{K_n}, \ n = 1,2,...$. For each $n$, let $\widehat{U_n}$ be the set of equivalence classes of irreducible unitary representations of $U_n$ and let $\widehat{U_n/K_n} \subseteq \widehat{U_n}$ be the set of $K_n$-spherical representations. The definition of the propagation gives a nice property allowing us to embed $\widehat{U_n/K_n}$ …


M. Effects Of Land Use And Habitat On Stream Fish Assemblages In Tributaries Of The Lower Bogue Chitto Watershed, Washington Parish, Louisiana, Brian Michael Ward Jan 2009

M. Effects Of Land Use And Habitat On Stream Fish Assemblages In Tributaries Of The Lower Bogue Chitto Watershed, Washington Parish, Louisiana, Brian Michael Ward

LSU Master's Theses

My research focused on how fish communities are responding to watershed land use and instream habitat in tributaries of the Lower Bogue Chitto River. To address this question I electrofished and seined 10 sites in four tributaries of the Bogue Chitto River a total of 4 times each over the course of 15 months in 2007 and 2008. I characterized habitat by measuring water flow, water depth, substrate size, woody debris, temperature, and dissolved oxygen, and quantified heterotrophic plate counts, nutrients, and chlorophyll a concentrations at the end of the sampling period each year. Watershed land cover was measured with …


Rate Of Change With Applications In Physics Problems, Maria Ludu Jan 2009

Rate Of Change With Applications In Physics Problems, Maria Ludu

LSU Master's Theses

In this thesis we approach the concept of Rate of Change as a mathematical model, and we apply it to a few physics problems. Its main goal is to help students to bridge concepts form mathematical models and the real life applications. We begin with a review of measurements, proportionality and similarity based on Euclidean geometry; then, we review linear and affine functions, and we introduce a mathematical model for the average and instantaneous rate of change. This mathematical model is applied to problems from physics following the four representations of functions: verbal, algebraic, tabular and graphical. By doing so, …


Efforts Of Coating And Testing High Aspect Ratio Microfabricated Nickel Gas Chromatography Columns, Arun Kumar K Paga Jan 2009

Efforts Of Coating And Testing High Aspect Ratio Microfabricated Nickel Gas Chromatography Columns, Arun Kumar K Paga

LSU Master's Theses

Gas chromatography (GC) is a widely used analytical technique, with applications in the chemical process industry, oil exploration, environmental monitoring, purification of substances, and general organic compound analysis. Although traditional GC’s are widely used they have their own disadvantages like high power consumption and long times for analysis. Several laboratories are working on the miniaturization of GC’s for rapid and onsite chemical analysis. Many researchers are currently working on the development of microfabricated columns for realizing a hand held GC sensor. Microfabricated nickel columns have been manufactured by Center for Advanced Microstructures & devices (CAMD), Baton Rouge. The columns are …