Chemistry Commons^™

Genetic Multivariate Calibration Methods For Near Infrared (Nir) Spectroscopic Determination Of Complex Mixtures, Durmuş Özdemi̇r, Betül Öztürk

Turkish Journal of Chemistry

The simultaneous determination of ternary mixtures of methylene chloride, ethyl acetate, and methanol using near infrared (NIR) spectroscopy and 4 different genetic algorithms based multivariate calibration methods was demonstrated. The 4 genetic multivariate calibration methods are genetic partial least squares (GPLS), genetic regression (GR), genetic classical least squares (GCLS) and genetic inverse least squares (GILS). The sample data set contains the NIR spectra of 63 ternary mixtures and covers the range from 900 to 2000 nm in 2 nm intervals. Of these 63 spectra, 42 were used as the calibration set, and 21 were reserved for the prediction purposes. Several …

Direct Dyes Derived From 4,4'-Diaminobenzanilide Synthesis, Characterization And Toxicity Evaluation Of A Disazo Symmetric Direct Dye, Georgeta Maria Simu, Sergiu Adrian Chicu, Nicole Morin, Walter Schmidt, Eugen Şişu

Turkish Journal of Chemistry

The synthesis of a new symmetric disazo direct dye containing the non--carcinogenic 4,4'-diaminobenzanilide as the middle component and salicylic acid as the coupling component is presented. The synthesized dye is an analog of the benzidine based dye C. I. Direct Yellow 1 (C. I. 22,250) and was analyzed by thin layer chromatography (TLC), electronic spectra (VIS) and mass spectroscopy (FAB-MS). The coloristic and fastness properties of the synthesized dye were determined and compared with those of C. I. Direct Yellow 1. The toxicities of the dye and of its precursors were evaluated by biological tests, using the process of metamorphosis …

Preparation, Spectroscopic Studies And Biological Activity Of Mono-Organotin(Iv) Derivatives Of Non-Steroidal Anti-Inflammatory Drugs, Azra Jalal, Saira Shahzadi, Khadiji Shahid, Saqib Ali, Amin Badshah, Mohammad Mazhar, Khalid Mohammed Khan

Turkish Journal of Chemistry

A set of 14 mono-organotin(IV) derivatives of general formulae n-BuSnClL_2 and n-BuSnL_3, where `L' are various non-steroidal anti-inflammatory drugs (NSAIDs), were synthesized and structurally characterized by vibrational, ^1H, ^{13}C and ^{119}Sn spectroscopies and mass spectrometry to propose their structure. Biological activity data (antibacterial, antifungal and cytotoxicity) of the synthesized complexes were compared with the precursors to establish the significance of the complexes.

Synthesis And Antitumor Activities Of Some New 4-(1-Naphthylidenamino)- And 4-(1-Naphthylmethylamino)-1,2,4-Triazol-5-One Derivatives, Nesli̇han Demi̇rbaş, Reyhan Uğurluoğlu

Turkish Journal of Chemistry

A series of 4-(1-naphthylidenamino)-1,2,4-triazol-5-one derivatives (3a-e) were synthesized by condensation of corresponding 3-alkyl-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones with 1-naphthaldehyde. Acetylation and alkylation of these compounds gave 4a-e and 5a-e, respectively. Sodium borohydride reduction of 1-naphthylidenamino derivatives afforded naphthylmethylamino derivatives, which were subsequently acetylated. Depending on the duration of the acetylation, mono or bis acetamide derivatives were obtained. The in vitro antitumor activities of some selected compounds were screened and compounds 3e, 5c, 6e and 9c} were found to be active.

Phenylpropanoid Glycosides From Linum Olympicum (Linaceae), Belma Konuklugi̇l, Özlem Bahadir

Turkish Journal of Chemistry

The lignan content of Linum olympicum Boiss. was investigated by HPLC and GC-MS in comparison with standards, and 2 phenylpropanoid glycosides, syringin (1) and coniferin (2), were isolated from the aerial parts. Identification of the 2 compounds was achieved by comparison with standards using TLC and HPLC and the structures of the isolated compounds were established by UV and ^1H-NMR analysis.

Methyl Bromide In Preindustrial Air: Measurements From An Antarctic Ice Core, Eric S. Saltzman, Murat Aydin, Warren J. De Bruyn, Daniel B. King, Shari A. Yvon-Lewis

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

This paper presents the first ice core measurements of methyl bromide (CH3Br). Samples from a shallow Antarctic ice core (Siple Dome, West Antarctica), ranging in mean gas dates from 1671 to 1942, had a mean CH3Br mixing ratio of 5.8 ppt. These results extend the existing historical record derived from air and Antarctic firn air to about 350 years before present. Model simulations illustrate that the ice core results are consistent with estimates of the impact of anthropogenic activity ( fumigation, combustion, and biomass burning) on the atmospheric CH3Br burden, given the large current uncertainties in the modern atmospheric CH3Br …

Ac Frequency Dependence Of Electroluminescent Zns Phosphor Panel Color, Farrah Shantell Boggess-Machado

Theses, Dissertations and Capstones

In this study, electroluminescent panels manufactured by Meadow River Enterprises were used to study the AC frequency dependence of their color. A project was developed to acquire their emittance color at various frequencies. Three frequencies were selected for the investigation. Data, obtained by measuring the spectrum at a constant excitation frequency, were taken for each of the three standard frequencies: 200 Hz, 1500 Hz, and 20 kHz. In general the higher the frequency, the bluer the emittance color of the panel. The lower the frequency, the more green the panel became. An explanation for this phenomenon, the frequency dependence of …

Development Of Electrochemical Sensors For Monitoring Glucose, Michael Nesbitt

Theses

The thesis focuses on evaluating calcium alginate as an immobilisation matrix for the oxidase enzyme glucose oxidase for the amperometric determination of glucose. The basic principles of enzymology and enzyme immobilisation is discussed followed by a review of a variety of first, second and third generation type enzyme electrodes. Amperometry as governed by the Cottrell equation and mass transfer models relating to amperometric electrodes are also considered.

Bovine serum albumin (BSA / GOx) enzyme electrode system was employed as a model to evaluate a calcium alginate immobilisation technique for glucose oxidase. The principal methods employed for enzyme immobilisation were:

• …

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

Chemistry & Biochemistry Faculty Publications

No abstract provided.

Tuning Polymeric Chiral Surfactants For Enhanced Enantiomeric Recognition In Micellar Electrokinetic Chromatography, Jepkoech Tarus

LSU Doctoral Dissertations

The research presented in this dissertation involves the synthesis, modification, characterization, and the application of polymeric surfactants in micellar electrokinetic chromatography (MEKC). Sodium undecenoyl-L-Leucinate (L-SUL) was synthesized and modified by use of alkali metal counterions, alcohols, and Triton X-102. Characterization of the modified poly-L-SUL was performed in order to elucidate the structural changes on the surfactants by use of four techniques. While surface tensiometry was used for the determination of the critical micelle concentration (cmc), fluorescence measurements were used for the determination of the polarity of the modified polymeric surfactants. The information about the size of the polymeric surfactants was …

New Insights Into The Binding Site Formation And The Performance Of Molecularly Imprinted Polymers, Hyunjung Kim

LSU Doctoral Dissertations

Molecularly imprinted polymers (MIPs) are finding important applications in the field of separation science, catalysis, sensor, and immunoassays. To optimize the performance of the MIPs, it is essential to understand the underlying mechanism of the process. This research focuses on understanding binding site formation and performance, and improvement of the MIPs. Chapter 1 introduces the concept of the MIPs, and binding isotherm and affinity distribution of heterogeneous binding sites in the MIPs. Chapter 2 describes fundamental studies conducted to understand the binding site formation of the MIPs. The number of binding sites (N) and the number average association constant (Kn) …

Analytical Separations Using Packed And Open-Tubular Capillary Electrochromatography, Constantina P. Kapnissi

LSU Doctoral Dissertations

The goal of the research reported in this dissertation is to develop packed and open-tubular capillary electrochromatographic methods for improved achiral and chiral separations of various classes of analytes. The first part of this research involves the separation of seven benzodiazepines by the use of the packed mode of capillary electrochromatography (CEC) and a 40 cm packed bed of Reliasil 3 μm C₁₈ stationary phase. Optimal conditions were established by varying the mobile phase, the amount of organic modifier, the buffer concentration, the applied voltage, and the column temperature. The second part of this research focuses on the open-tubular …

Evaluation Of Fluorapatite As A Waste-Form Material, Dennis W. Lindle, Oliver Hemmers, Dale L. Perry

Separations Campaign (TRP)

This research attempts to develop a waste form for disposing of the zirconium fluoride fission product waste stream. Fluorapatite, a naturally-occurring fluorinated calcium phosphate, has been identified as a potential matrix for the entombment of this waste stream. If the efficacy of fluorapatite-based wastestorage can be demonstrated, then new and potentially more efficient options for handling and separating high-level wastes, based on fluoride-salt extraction, will become feasible.

The research effort has been divided along two parallel paths: the Fabrication Path, led by collaborators at the Khlopin Radium Institute (KRI) in St. Petersburg, Russia; and the Characterization Path, led by researchers …

A Molecular Switch Created By In Vitro Recombination Of Nonhomologous Genes, Sarah F. Mitchell

Chemistry and Biochemistry Faculty Works

We have created a molecular switch by the in vitro recombination of nonhomologous genes and subjecting the recombined genes to evolutionary pressure. The gene encoding TEM1 β-lactamase was circularly permuted in a random fashion and subsequently randomly inserted into the gene encoding Escherichia coli maltose binding protein. From this library, a switch (RG13) was identified in which its β-lactam hydrolysis activity was compromised in the absence of maltose but increased 25-fold in the presence of maltose. Upon removal of maltose, RG13's catalytic activity returned to its premaltose level, illustrating that the switching is reversible. The modularity of RG13 was demonstrated …

Study Of Structural And Magnetic Properties Of Iron-Rich Mixed Rare-Earth Nddyfe (17-Y-X)Coxsiy Compounds, Kishore Kamaraju, Jinbo Yang, William B. Yelon, Oran Allan Pringle, M. S. Kim, Qingsheng Cai, William Joseph James

Physics Faculty Research & Creative Works

A series of NdDyFe(17-y-x)CoxSiy solid solutions with = 2 and 3 and = 0.5 1.0 and 1.5 were prepared by induction melting stoichiometric amounts of high-purity elements. The postannealed samples consist of two phases belonging to the space groups R3 m and P63 mmc . The lattice parameters and the unit cell volumes were calculated from the refinements of the magnetic and structural unit cells using the FULLPROF version of the Rietveld program. For a fixed content of Co, the maximum Curie temperatures (305 C to 405 C) were observed in samples with = 1 and having two phases, a …

Gas Phase Studies Of Molecular Clusters Containing Metal Cations, And The Ion Mobility Of Styrene Oligomers, Edreese Housni Alsharaeh

Theses and Dissertations

This study is divided into three parts. Part I deals with the mechanism of the self-initiated polymerization (or thermal polymerization) of styrene in the gas phase. In this work, we present the first direct evidence for the thermally self-initiated polymerization of styrene in the gas phase. Our approach is based on on-line analysis of the gas phase Oligomers by mass-selected ion mobility. The mobility measurements provide structural information on the ionized oligomers based on their collision cross-sections (Ω) which depend on the geometric shapes of the ions. Theoretical calculations of possible structural candidates of the Oligomers ions are then used …

Methods Development And Application Of Two Dimensional Chromatography And Tandem Mass Spectrometry In Proteomics, Brett Romain Wenner

University of Kentucky Doctoral Dissertations

Although molybdenum blue solutions have been known for more than twocenturies, an understanding of their chemical nature is only beginning to emerge.This dissertation aimed at elucidating the structural nature of the polydisperse,nanoscopic components in the solution phases and the solid states of partiallyreduced polyoxomolybdate (Mo-POM). The study offered at least fourcontributions to the area: (1) a rational protocol for the molecular recognition ofMo-POM with de novo organic hosts. (2) demonstration of kinetic precipitation ofa dynamic mixture of polyoxomolybdates and application of the technique to thestudy of the dynamic mixture by TEM (3) characterization of the Mo-POMnanostructures by an unusual combination …

Metallic Single-Walled Silicon Nanotubes, Jaeil Bai, Xiao Cheng Zeng, Hideki Tanaka, J. Y. Zeng

Xiao Cheng Zeng Publications

Atomistic computer-simulation evidences are presented for the
possible existence of one-dimensional silicon nanostructures: the
square, pentagonal, and hexagonal single-walled silicon nanotubes
(SWSNTs). The local geometric structure of the SWSNTs
differs from the local tetrahedral structure of cubic diamond
silicon, although the coordination number of atoms of the SWSNTs
is still fourfold. Ab initio calculations show that the SWSNTs
are locally stable in vacuum and have zero band gap, suggesting
that the SWSNTs are possibly metals rather than wide-gap
semiconductors.

Optimization Of Conditions For Studies Of Protein Unfolding By Hydrogen Exchange/Mass Spectrometry, A.S. Raza, David L. Smith

Department of Chemistry: Faculty Publications

Understanding the forces driving protein folding and aggregation is an essential step in developing means for controlling these important processes. Amide hydrogen exchange, coupled with mass spectrometry, has become an important method for studying protein unfolding and refolding. To extend procedures developed to study unfolding of relatively soluble proteins to less soluble, aggregation-prone proteins requires special considerations. This publication describes a general strategy developed using yeast transaldolase, which aggregates easily under conditions required to study its unfolding. Results presented here show that reducing the protein concentration to the nanomolar range is essential for managing aggregation of transaldolase. In addition, the …

Microelectrophoresis System Utilizing Conductivity Detection Analyzing Biological Molecues, Michelle Galloway

LSU Doctoral Dissertations

Microfabrication technology has proven to be a valuable tool for creating polymer-based devices utilized in chemical and biochemical assays. Although, reducing the size of the device allows for short analysis times and reduces the reagent demand to ultrasmall volumes (< 1 nanoliter), a resulting consequence is the constraint placed on the limits of detection associated with the detector hardware required for readout. To overcome such constraints, laser-induced fluorescence (LIF) is often employed as a detection method as it provides low detection limits, which approach the single molecule level. Unfortunately, most LIF systems do not offer the benefits of miniaturization, with the detector components (i.e. laser, optics, filters) often times requiring a much larger footprint compared to the device. Another readout strategy that has shown promise for these devices is conductivity detection. Detection can be accomplished using either conventional-size or microfabricated electrodes, which can be integrated on the device. Although conductivity has been commonly used to detect inorganic or small organic species, the potential for detection of biological species has received little attention. In this work, an integrated conductivity detector was developed for the analysis of amino acids, peptides, proteins, and oligonucleotides (double-stranded DNA). Using the detector, mass detection sensitivities in the range of 10^-18 - 10^-21 moles were achieved. To increase the throughput of the system a state-of-the-art, multichannel device with a conductivity array detector was devised. This device, which consists of a 16-channel fluidic network and a printed circuit board, is geared toward automating three-processing steps onto a single fluidic platform including purification, preconcentration and detection for downstream parallel processing.

Synthesis, Characterization And Physical Studies Of Ligand Bridged Bimetallic Aqua Ruthenium (Ii) Polypyridyl Complexes, Matthew Thomas Mongelli

Seton Hall University Dissertations and Theses (ETDs)

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A Novel Tiq2-Assisted Solar Photocatalytic Batch-Process Disinfection Reactor For The Treatment Of Biological And Chemical Contaminants In Domestic Drinking Water In Developing Countries, E. F. Duffy, F. Al Touati, S. C. Kehoe, O. A. Mcloughlin, L. W. Gill, W. Gernjak, I. Oller, M. I. Maldonado, S. Malato, John Cassidy, R. H. Reed, K. G. Mcguigan

Articles

he technical feasibility and performance of photocatalytic Ti02 coatings in batch-process solar disinfection (SODIS) reactors to improve potability of drinking water in developing countries have been studied. Borosilicate glass and PET plastic SODIS reactors fitted with flexible plastic inserts coated with Ti02 powder were shown to be 2(Jt1o and 25% more effective, respectively, than standard SODIS reactors for the inactivation of E. coli K12. Isopropanol at 100 ppm concentration levels was observed to be completely photodegraded after 24 h continuous exposure to lOG mW/cm2 simulated sunlight in a similar solar photocatalytic disinfector (SPC-DIS) reactor. The technique for p roducing the …

Investigation Of Optical Spectroscopy Techniques For On-Line Materials Accountability In The Solvent Extraction Process, Gary Cerefice, Kenneth Czerwinski

Safeguards Campaign (TRP)

The goal of this project is to examine the potential for using optical spectroscopy techniques, such as UV-Visible Spectroscopy and Laser Fluorescence Spectroscopy, for special nuclear materials accountability applications for the UREX+ and other solvent extraction processes. To increase the inherent proliferation resistance of the solvent extraction process, it is necessary to develop on-line techniques to directly measure the concentrations of special nuclear materials in-process. By providing on-line materials accountability for the processes, the potential for covert diversion of the materials streams becomes much more difficult to implement. On-line monitoring of material streams will also allow for improved plant operation, …

Corrosion Of Steel By Lead Bismuth Eutectic, John Farley, Allen L. Johnson, Dale L. Perry

Transmutation Sciences Materials (TRP)

There is an active international interest in lead-bismuth eutectic and similar liquid lead systems because of the relevance to the transmutation of nuclear waste, fast reactors, and spallation neutron sources. A successful program in nuclear waste processing that includes transmutation in accelerator-driven systems and fast reactors, would significantly decrease the space requirements for geological repositories.

Materials in these systems must be able to tolerate high neutron fluxes, high temperatures, and chemical corrosion. For lead bismuth eutectic (LBE) systems, there is an additional challenge because the corrosive behaviors of materials in LBE are not well understood. Most of the available information …

Environment-Induced Degradation And Crack-Growth Studies Of Candidate Target Materials, Ajit K. Roy

Transmutation Sciences Materials (TRP)

The primary objective of this task is to evaluate the effect of environmental and mechanical parameters on environment induced degradations of candidate target structural materials for applications in spallation-neutron-target systems, such as accelerator-driven systems for the transmutation of waste. The materials selected for evaluation and characterization are martensitic stainless steels including Alloys HT-9, EP-823 and Type 422 stainless steel (SS).

More recently, this experimental program has been expanded to evaluate the effect of molten lead-bismuth eutectic (LBE) on the corrosion behavior of target structural materials in the presence of oxygen. Since the Materials Performance Laboratory (MPL) at UNLV currently cannot …

Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics, Samir Moujaes, Yitung Chen

Transmutation Sciences Materials (TRP)

The corrosion of structural materials is a major concern for the use of lead-bismuth eutectic (LBE) systems for nuclear applications such as in transmuter targets or fast reactors. Corrosion in liquid metal systems can occur through various processes, including, for example, dissolution, formation of inter-metallic compounds at the interface, and penetration of liquid metal along grain boundaries. Predicting the rate of these processes depends on numerous system operational factors: temperature, system geometry, thermal gradients, solid and liquid compositions, and velocity of the liquid metal, to name a few. Corrosion, along with mechanical and/or hydraulic factors, often contributes to component failure. …

Development Of A Systems Engineering Model Of The Chemical Separations Process, Yitung Chen, Darrell Pepper, Sean Hsieh

Separations Campaign (TRP)

The chemical processing of used nuclear fuel is an integral component of any strategy for the transmutation of nuclear waste. Due to the large volume of material that must be handled in this first step of the transmutation process, the efficiency of the separations process is a key factor in the potential economic viability of the transmutation strategies. The ability to optimize the chemical separation systems is vital to ensure the feasibility of the transmutation program.

Systems analysis, or total systems modeling, is one of the strongest tools available to researchers for understanding and optimizing complex systems such as chemical …

Nuclear Criticality, Shielding, And Thermal Analyses Of Separations Processes For The Transmutation Fuel Cycle, William Culbreth

Separations Campaign (TRP)

The first step in any transmutation strategy is the separation of radionuclides in used nuclear fuel. The current separation strategy supporting the Advanced Fuel Cycle Initiative (AFCI) program is based on the use of a solvent extraction separation process to separate the actinides, fission products, and uranium from used commercial nuclear fuel, and on the use of pyrochemical separation technologies to process used transmuter fuels. To separate the fission products and transuranic elements from the uranium in used fuel, the national program is developing a new solvent extraction process, the Uranium Extraction Plus, or UREX+, process based on the traditional …

Development, Fabrication And Study Of Fullerene-Containing Carbon Material (Fcc) For Immobilization Of Iodine: Progress Reports 1-1 And 1-2, Michael Savopulo, Boris E. Burakov

Separations Campaign (TRP)

Immobilization of highly radioactive and long-lived isotope of ¹²⁹I, which is a fission product in spent nuclear fuel, requires development of new durable host-materials. Such materials should be characterized with the following principal features:

• High loading capacity to iodine incorporation
• Chemical durability and radiation resistance in order to prevent iodine release over long time (higher than 105 years) storage under conditions of underground repository of radioactive wastes
• Possibility to use iodine-doped material as a target for iodine transmutation.

Iodine is a very volatile chemical element, and even its chemically strong compounds such as AgI and CuI are not stable …

Development, Fabrication And Study Of Fullerene-Containing Carbon Material (Fcc) For Immobilization Of Iodine: Progress Report 1-3, Michael Savopulo, Boris E. Burakov

Separations Campaign (TRP)

During previous reporting periods we studied properties of iodine doped FCC in comparison with activated carbon. An additional goal was to investigate the possibility to convert iodine doped FCC and activated carbon into ceramic-like material avoiding iodine loss. In order to obtain ceramic based on C_xN_y with fullerene structure we decided to carry out gamma irradiation of iodine doped samples in nitrogen atmosphere (0.7 atm. N₂). It was found that iodine doping and irradiation caused principal changes in composition of FCC such as substituting of fullerene C₆₀ and graphite (both formed by benzene-like carbon …