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Full-Text Articles in Physical Sciences and Mathematics

Determining Crystal Thickness By Measuring Optical Rotation In Chiral Crystals, Cori Bruce, James Bish, Jamie Walker Jan 2003

Determining Crystal Thickness By Measuring Optical Rotation In Chiral Crystals, Cori Bruce, James Bish, Jamie Walker

The Corinthian

In this experiment, it will be shown that the linear relationship between pathlength and observed rotation can be applied to predict the pathlength based on the observed rotation. It should be noted, however, that the method devised will only work for chiral crystals. When aqueous NaC103 solution evaporates two rotamers will form that will rotate plane-polarized light in equal but opposite directions. Hence, the crystals must be separated to obtain linear correlations in regards to the two rotamers.


Argon Eximer Emission From High-Pressure Microdischarges In Mental Capillaries, R. Mohan Sankaran, Konstantinos P. Giapis, Mohamed Moselhy, Karl H. Schoenbach Jan 2003

Argon Eximer Emission From High-Pressure Microdischarges In Mental Capillaries, R. Mohan Sankaran, Konstantinos P. Giapis, Mohamed Moselhy, Karl H. Schoenbach

Bioelectrics Publications

We report on argon excimer emission from high-pressure microdischarges formed inside metal capillaries with or without gas flow. Excimer emission intensity from a single tube increases linearly with gas pressure between 400 and 1000 Torr. Higher discharge current also results in initial intensity gains until gas heating causes saturation or intensity drop. Argon flow through the discharge intensifies emission perhaps by gas cooling. Emission intensity was found to be additive in prealigned dual microdischarges, suggesting that an array of microdischarges could produce a high-intensity excimer source.


Low-Flow Helmholtz Resonator For Molar Mass Detection, Brackman Amy, Amanda Kea, Kenneth Mcgill Jan 2003

Low-Flow Helmholtz Resonator For Molar Mass Detection, Brackman Amy, Amanda Kea, Kenneth Mcgill

The Corinthian

A simple apparatus was constructed for an undergraduate physical chemistry laboratory to determine a mathematical model of wavelike motion. The apparatus was assembled by attaching an airflow valve connected to a tank of argon gas to a GC column, thus creating regulated airflow. The air was manipulated to gently flow over a small sensitive microphone that was attached to an inexpensive resonator. A model will be developed to measure the speed of sound that will lead to the measurement of the molar mass.


Structural And Biochemical Analyses Of Dna And Rna Binding By A Bifunctional Homing Endonuclease And Group I Intron Splicing Factor, Jill M. Bolduc, P. Clint Spiegel, Pivali Chatterjee, Kristina L. Brady, Maureen E. Downing, Mark G. Caprara, Richard B. Waring, Barry L. Stoddard Jan 2003

Structural And Biochemical Analyses Of Dna And Rna Binding By A Bifunctional Homing Endonuclease And Group I Intron Splicing Factor, Jill M. Bolduc, P. Clint Spiegel, Pivali Chatterjee, Kristina L. Brady, Maureen E. Downing, Mark G. Caprara, Richard B. Waring, Barry L. Stoddard

Chemistry Faculty and Staff Publications

We determined the crystal structure of a bifunctional group I intron splicing factor and homing endonuclease, termed the I-AniI maturase, in complex with its DNA target at 2.6 Å resolution. The structure demonstrates the remarkable structural conservation of the (3-sheet DNA-binding motif between highly divergent enzyme subfamilies. DNA recognition by I-AniI was further studied using nucleoside deletion and DMS modification interference analyses. Correlation of these results with the crystal structure provides information on the relative importance of individual nucleotide contacts for DNA recognition. Alignment and modeling of two homologous maturases reveals conserved basic surface residues, distant …


Sonogashira Coupling Routes To Ortho-Alkynl-And- Fused-Ring Sydnones, Andrew John Weisner Jan 2003

Sonogashira Coupling Routes To Ortho-Alkynl-And- Fused-Ring Sydnones, Andrew John Weisner

Browse all Theses and Dissertations

In the present work, suitably functionalized arylsydnones were used to synthesize a variety of ortho-alkynyl sydnones both as potential precursors to novel sydnoquinolines and to provide non-linear optical (NLO) species of interest to Wright-Patterson Air Force Base (WPAFB). The versatile intermediate, 3-(2-(trimethylsilylethynyl)phenyl)sydnone, was prepared in good yield by the coupling of 3-(2-iodophenyl)sydnone with trimethylsilyl acetylene under Sonogashira conditions. From this intermediate, several ortho-alkynyl sydnones were prepared via a one-pot desilylation with tetrabutylammonium fluoride and Sonogashira coupling with para-substituted aryl iodides. In addition, a three-reaction-in-one-pot procedure was developed to access some of these species directly from 3-(2- iodophenyl)-sydnone. Subsequent reaction of …


Urer, The Transcriptional Activator Of The Proteus Mirabilis Urease Gene Cluster, Is Required For Urease Activity And Virulence In Experimental Urinary Tract Infections, Jonathan D. Dattelbaum, C. Virginia Lockatell, David E. Johnson, Harry L.T. Mobley Jan 2003

Urer, The Transcriptional Activator Of The Proteus Mirabilis Urease Gene Cluster, Is Required For Urease Activity And Virulence In Experimental Urinary Tract Infections, Jonathan D. Dattelbaum, C. Virginia Lockatell, David E. Johnson, Harry L.T. Mobley

Chemistry Faculty Publications

Proteus mirabilis, a cause of complicated urinary tract infection, produces urease, an essential virulence factor for this species. UreR, a member of the AraC/XylS family of transcriptional regulators, positively activates expression of the ure gene cluster in the presence of urea. To specifically evaluate the contribution of UreR to urease activity and virulence in the urinary tract, a ureR mutation was introduced into P. mirabilis HI4320 by homologous recombination. The isogenic ureR::aphA mutant, deficient in UreR production, lacked measurable urease activity. Expression was not detected in the UreR-deficient strain by Western blotting with monoclonal antibodies raised against UreD. Urease …


Double Stranded Dna-Binding Studies Of Potential Rhodium(Ll) Antitumor Complexes, Amity Elizabeth Burr Jan 2003

Double Stranded Dna-Binding Studies Of Potential Rhodium(Ll) Antitumor Complexes, Amity Elizabeth Burr

Honors Theses

In 1952, Dwyer and coworkers began testing a series of metal complexes for potential inhibition of cancer cell proliferation in animals.[l] The complexes tested were unsuitable for such studies due to their high toxicity. Therefore, no further work was done on the project. However, in 1965, Rosenberg and coworkers revisited the possibility of potential metal-based drugs. Serendipitously, they discovered that cis-diamminedichloroplatinum(lI) (cisplatin) inhibits cell division in E. coli.[2] Further studies of this and other platinum compounds revealed inhibition of tumor cell lines sarcoma 180 and leukemia LI2l0 in mice.[l] Cisplatin was approved by the Food and Drug Administration in 1970 …


Synthesis Of Montiporynes A And B, Traci Jenelle Speed Jan 2003

Synthesis Of Montiporynes A And B, Traci Jenelle Speed

Honors Theses

This thesis reports the first complete synthesis of monriporynes A and B. isomeric diacetylenes that bear α, β unsaturated ketone functionalities. Recently isolated from the stony coral Montipora sp. these compounds are reported to possess in vitro cytotoxic activity against several human solid tumor cells. We have synthesized both isomers in three simple steps. In the first step, l-iodononyne was prepared by reacting 1-nonyne with N-iodosuccinimide and a catalytic amount of silver nitrate. This iodoalkyne was then coupled with propargyl alcohol using copper iodide as the catalyst to give 2,4dodecadiynyl alcohol. Finally, the diacetylenic alcohol was subjected to the Swern …


Deuterium Nmr Studies Of Bulk And Silica-Absorbed Polystyrene, Macduff O. Okuom, Jinhua Yang, Frank D. Blum Jan 2003

Deuterium Nmr Studies Of Bulk And Silica-Absorbed Polystyrene, Macduff O. Okuom, Jinhua Yang, Frank D. Blum

Chemistry Faculty Research & Creative Works

Thin polymer films are used in applications such as electronics, biomedical devices and coatings. As the trend to make the devices smaller continues, a film's influence on a material's overall properties becomes more prominent. Previous studies have shown that thin polymer films have characteristics slightly different from those of bulk polymers. Film behavior has been characterized by examining thermal expansion, diffusion, conformation, density and glass transitions. The dynamics of glassy polystyrene has been investigated using a wide variety of theoretical and experimental methods. Schaefer et al., using 13C NMR, reported that ~7% of phenyl rings in polystyrene undergo -flips. Using …


Simulation Of Dynamic Electrochemical Processes, John Cassidy Jan 2003

Simulation Of Dynamic Electrochemical Processes, John Cassidy

Articles

This work is designed to introduce electrochemists in a tutorial manner to the basics of modeling of electrochemical systems based primarily on diffusion equations. There is an introduction to analytical and numerical methods with examples taken from typical electrochemical experiments. The Laplace transform is used to derive the Cottrell equation and chronopotentiometry. The response of an electrode to a Gaussian concentration profile is detailed. Laplace’s equation is solved for a simple cell to determine the potential distribution. Discrete methods are employed to calculate the current time behavior following a potential step using the explicit finite difference method. Cyclic voltammetry is …


A Solvent-Free Claisen Condensation Reaction For The Organic Laboratory, John J. Esteb, Matthew B. Stockton Jan 2003

A Solvent-Free Claisen Condensation Reaction For The Organic Laboratory, John J. Esteb, Matthew B. Stockton

Scholarship and Professional Work - LAS

An experiment involving the Claisen condensation reaction for a first-year organic chemistry laboratory is presented. Claisen condensations are routinely covered in organic textbooks but owing to the long reaction times required to reach equilibrium in solution they are seldom explored in the undergraduate teaching laboratory. In this experiment, potassium tert-butoxide and ethyl phenylacetate are heated to 100 °C for 30 minutes under solvent-free conditions to produce 2,4-diphenyl acetoacetate in 80% yield. The solvent-free nature of this procedure greatly reduces the quantity of waste generated by students relative to typical carbonyl condensation experiments.


The Microwave Spectrum, Ab Initio Analysis, And Structure Of The Fluorobenzene–Hydrogen Chloride Complex, M. Eugenia Sanz, Sonia Antolinez, Jose L. Alonso, Juan C. Lopez, Robert L. Kuczkowski, Sean A. Peebles, Rebecca A. Peebles, Faith C. Boman, Elfi Kraka, Dieter Cremer Jan 2003

The Microwave Spectrum, Ab Initio Analysis, And Structure Of The Fluorobenzene–Hydrogen Chloride Complex, M. Eugenia Sanz, Sonia Antolinez, Jose L. Alonso, Juan C. Lopez, Robert L. Kuczkowski, Sean A. Peebles, Rebecca A. Peebles, Faith C. Boman, Elfi Kraka, Dieter Cremer

Sean A. Peebles

The fluorobenzene–hydrogen chloride π-hydrogen-bonded complex has been studied by high resolution microwave spectroscopy and ab initio calculations. Rotational spectra of the C6H5F–H35Cl, C6H5F–H37Cl, and C6D5F–H35Cl isotopomers were assigned using pulsed molecular beam techniques in a Fourier-transform microwave spectrometer. The spectra are consistent with a structure of the complex in which the HCl is above the fluorobenzene ring near the ring center, similar to the benzene–HCl prototype dimer. An analysis of the inertial data and the chlorine quadrupole coupling tensor results in two mathematically possible locations for the HCl subunit with respect to the fluorobenzene arising from sign ambiguities in interpreting …


Resonance Two Photon Ionization Study Of Binary Clusters Of Styrene With Polar Molecules, Hatem Ahmed Mahmoud Jan 2003

Resonance Two Photon Ionization Study Of Binary Clusters Of Styrene With Polar Molecules, Hatem Ahmed Mahmoud

Theses and Dissertations

One-color resonance two-photo ionization (R2PI) spectra of mixed clusters of styrene molecule (S) with polar molecules [water (W), methanol (M), ethanol (E), and trifuoroethanol (T)] were measured through the S1←S0 transition of the styrene molecule. The spectra reveal a rapid increase in complexity with the number of polar molecules in the cluster, associated with van der Waal modes and isomeric forms. The spectral shifts of the cluster origins from the S1-S0 transition of the bare styrene molecule reflect the nature of the intermolecular interactions within the binary clusters. The obtained R2PI spectra xv were compared with the spectra of the …


Chemical Vapor Deposited Diamond Films For Self-Referencing Fiber Optic Raman Probes, Sacharia Albin, Jianli Zheng, Bing Xiao, John B. Cooper, Robert B. Jeffers, Sonia Antony Jan 2003

Chemical Vapor Deposited Diamond Films For Self-Referencing Fiber Optic Raman Probes, Sacharia Albin, Jianli Zheng, Bing Xiao, John B. Cooper, Robert B. Jeffers, Sonia Antony

Chemistry & Biochemistry Faculty Publications

Diamond thin films grown by the microwave plasma enhances chemical vapor deposition (CVD) process have been investigated as an internal reference in fiber optic remote Raman sensing. The growth parameters have been optimized for diamond thin films on quarts substrates using a gas mixture of methane, carbon dioxide, and hydrogen. The resulting films exhibit essentially no Raman spectral background while exhibiting a strong Raman peak at 1332 cm-¹. The films are used as an internal reference in the quantitative measurement of chemical concentration using remote fiber optic Raman sensing. Internal referencing is accomplished by normalizing all spectral intensities …


A Hmm Based Semantic Analysis Framework For Sports Game Event Detection, Gu Xu, Yu-Fei Ma, Hong-Jiang Zhang, Shiqiang Yang Jan 2003

A Hmm Based Semantic Analysis Framework For Sports Game Event Detection, Gu Xu, Yu-Fei Ma, Hong-Jiang Zhang, Shiqiang Yang

Chemistry Faculty Research & Creative Works

Video events detection or recognition is one of important tasks in semantic understanding of video content. Sports game video should be considered as a rule-based sequential signal. Therefore, it is reasonable to model sports events using hidden Markov models. In this paper, we present a generic, scalable and multilayer framework based on HMMs, called SG-HMMs (sports game HMMs), for sports game event detection. At the bottom layer of this framework, event HMMs output basic hypotheses based on low-level features. The upper layers are composed of composition HMMs, which add constraints on those hypotheses of the lower layer. Instead of isolated …


Molecular Mass And Dynamics In Pma-D₃ In The Glass Transition Region, Burak Metin, Frank D. Blum Jan 2003

Molecular Mass And Dynamics In Pma-D₃ In The Glass Transition Region, Burak Metin, Frank D. Blum

Chemistry Faculty Research & Creative Works

The segmental dynamics through the glass transition region, by which the glassy polymer becomes rubbery, are not well understood. Free volume, thermodynamic and kinetic theories have been used to describe the phenomenon behind the glass transition and some of those theories were tested with computer simulations. Different experimental techniques, such as NMR, thermo-mechanical analysis (TMA), differential scanning calorimetry (DSC), dilatometry and dynamic mechanical analysis (DMA) have all been also used to probe this important phenomena. Deuterium (2H) NMR has been a valuable tool for the investigation of the dynamics of macromolecules. Deuteration of macromolecules at specific locations on the chains …


Bismuth Compounds In Organic Synthesis. Deprotection Of Ketoximes Using Bismuth Bromide-Bismuth Triflate, Ram Mohan, Joshua Arnold, Patrick Hayes, Robert Kohaus Jan 2003

Bismuth Compounds In Organic Synthesis. Deprotection Of Ketoximes Using Bismuth Bromide-Bismuth Triflate, Ram Mohan, Joshua Arnold, Patrick Hayes, Robert Kohaus

Scholarship

Ketoximes undergo deprotection in CH3CN/acetone/H2O (3:6:1) in the presence of 20–40 mol% BiBr3/5 mol% Bi(OTf)3. Bismuth(III) salts are relatively non-toxic, insensitive to air and inexpensive. These features coupled with the use of a relatively non-toxic solvent system make this method an attractive alternative to existing routes for deprotection of ketoximes.


Comparison Between The Ultraviolet Emission From Pulsed Microhollow Cathode Discharges In Xenon And Argon, Isfried Petzenhauser, Leopold D. Biborosch, Uwe Ernst, Klaus Frank, Karl H. Schoenbach Jan 2003

Comparison Between The Ultraviolet Emission From Pulsed Microhollow Cathode Discharges In Xenon And Argon, Isfried Petzenhauser, Leopold D. Biborosch, Uwe Ernst, Klaus Frank, Karl H. Schoenbach

Bioelectrics Publications

We measured the dynamic I–V characteristics and vacuum ultraviolet (VUV) emission lines of the second continuum in xenon (170 nm) and argon (130.5 nm) from pulsed microhollow cathode discharges (MHCD). For pulse lengths between 1 and 100 μs the dynamic I–V characteristics are similar in both inert gases. Only the time variation of the VUV emission line at 170 nm for xenon can be related to the dimer excited states. In argon the energy transfer between the Ar*2 dimers and the oxygen impurity atoms is responsible for a qualitatively different time behavior of the resonance line at 130.5 nm. …


On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Year 4, January 2003, Daniel A. Burgard, Gary A. Bishop, Mitchell J. Williams, Donald H. Stedman Jan 2003

On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Year 4, January 2003, Daniel A. Burgard, Gary A. Bishop, Mitchell J. Williams, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.


On-Road Remote Sensing Of Automobile Emissions In The Labrea Area: Year 2, Mitchell J. Williams, Gary A. Bishop, Donald H. Stedman Jan 2003

On-Road Remote Sensing Of Automobile Emissions In The Labrea Area: Year 2, Mitchell J. Williams, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.


On-Road Remote Sensing Of Automobile Emissions In The Phoenix Area: Year 4, November 2002, Gary A. Bishop, Daniel A. Burgard, Mitchell J. Williams, Donald H. Stedman Jan 2003

On-Road Remote Sensing Of Automobile Emissions In The Phoenix Area: Year 4, November 2002, Gary A. Bishop, Daniel A. Burgard, Mitchell J. Williams, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.


Histological Effect Of Ascocotyle Tenuicollis (Digenea: Heterophyidae) Metacercarial Infection On The Heart Of Fundulus Heteroclitus (Teleostei: Cyprinodontidae), Toni Hicks, Edna Steele Jan 2003

Histological Effect Of Ascocotyle Tenuicollis (Digenea: Heterophyidae) Metacercarial Infection On The Heart Of Fundulus Heteroclitus (Teleostei: Cyprinodontidae), Toni Hicks, Edna Steele

Journal of the South Carolina Academy of Science

No abstract provided.


South Carolina Statewide Science Safety Project., Linda Sinclair, Jack Gerlovich, Rahul A. Parsa Jan 2003

South Carolina Statewide Science Safety Project., Linda Sinclair, Jack Gerlovich, Rahul A. Parsa

Journal of the South Carolina Academy of Science

No abstract provided.


2002 & 2003 Annual Meeting Extended Abstracts Jan 2003

2002 & 2003 Annual Meeting Extended Abstracts

Journal of the South Carolina Academy of Science

No abstract provided.


Maternal And Sibling Influences On Seed Germination Of Aegilops Triuncialis Erin, Erin Scott, Andrew R. Dyer Jan 2003

Maternal And Sibling Influences On Seed Germination Of Aegilops Triuncialis Erin, Erin Scott, Andrew R. Dyer

Journal of the South Carolina Academy of Science

No abstract provided.


Scas Officers And Council Members 2003 - 2004 Jan 2003

Scas Officers And Council Members 2003 - 2004

Journal of the South Carolina Academy of Science

No abstract provided.


A Five-Channel, Single Detector, Emission Rmote Sensor (Presentation), Mitchell J. Williams, Donald H. Stedman, Gary A. Bishop, Richard W. Quine Jan 2003

A Five-Channel, Single Detector, Emission Rmote Sensor (Presentation), Mitchell J. Williams, Donald H. Stedman, Gary A. Bishop, Richard W. Quine

Fuel Efficiency Automobile Test Publications

No abstract provided.


Feat Standard Operating Procedures, Donald H. Stedman, Gary A. Bishop Jan 2003

Feat Standard Operating Procedures, Donald H. Stedman, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.


Feat Monochromater User's Guide, Gary A. Bishop Jan 2003

Feat Monochromater User's Guide, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.


Stably Folded De Novo Proteins From A Designed Combinatorial Library, David Moffet Jan 2003

Stably Folded De Novo Proteins From A Designed Combinatorial Library, David Moffet

Chemistry and Biochemistry Faculty Works

Binary patterning of polar and nonpolar amino acids has been used as the key design feature for constructing large combinatorial libraries of de novo proteins. Each position in a binary patterned sequence is designed explicitly to be either polar or nonpolar; however, the precise identities of these amino acids are varied extensively. The combinatorial underpinnings of the "binary code" strategy preclude explicit design of particular side chains at specified positions. Therefore, packing interactions cannot be specified a priori. To assess whether the binary code strategy can nonetheless produce well-folded de novo proteins, we constructed a second-generation library based upon a …