Chemistry Commons^™

Optimization Of Microwave-Assisted Acid Digestion Method For Determination Of Trace Elements In Coal And Coal Fly Ash, Dejan Savic

Masters Theses & Specialist Projects

In most of the analytical and environmental laboratories today inductively coupled plasma (ICP) is a method of choice for analysis of trace metal elements present in coal and coal combustion products. This method requires use of liquid samples, so all coal and coal combustion products must be digested prior to analysis by ICP. Traditionally an open-air hot-plate acid digestion method published as ASTM D6357-04 was used to extract all trace metal elements into solution.

Recent development of microwave systems designed for digestions under extreme acidic conditions and high temperatures and pressures shifted focus toward more rapid and precise microwave-assisted digestion …

Chemistry And The Automotive Industry, Jeremy Pedigo

Masters Theses & Specialist Projects

This thesis covers the use of chemistry in the automotive industry with emphasis on environmental compliance via chemical reporting by database and internal Energy Dispersive X-ray Fluorescence (XRF) screening, third party laboratory material testing, and the future of the chemist in the United States (U.S.) automotive industry. The third party testing was performed at Western Kentucky University (WKU) via the Materials Characterization Center (MCC), Institute for Combustion Science and Environmental Technology (ICSET) Thermodynamics Laboratory, and using the Scanning Electron Microscope/Energy Dispersive X-ray Spectrometer (SEM/EDX) managed by the WKU Biotechnology Center. Furthermore, the tests conducted were used to investigate material defects, …

Ua66/1/5 Icset - Institute For Combustion Science & Environmental Technology, Wku Ogden College Of Science & Engineering

WKU Administration Documents

History and overview of the work of the WKU Institute for Combustion Science & Environmental Technology through 2008.

A Modified Route To Cyclopenta[C]Thophenes Via Grignard Reagents, Amber Bell

Masters Theses & Specialist Projects

The synthesis of cyclopenta[c]thiophenes is sparsely found in literature due to the several difficulties of their synthesis. Our research has shown that we could modify a previously known route to 1,3-disubstituted cyclopenta[c]thiophenes using traditional Grignard chemistry. Along the way we discovered the synthetic route we were using had several omissions. Therefore, we were required to completely fill in missing experimentals in order to obtain each cyclopenta[c]thiophene intermediate, in high purity and good yield. In addition, we were able to fully characterize via NMR, our intermediates which was found in the literature. Finally, we were able to show using 'H 13 …

Delivery Of Itv Chemistry Classes, David Martin

Masters Theses & Specialist Projects

Western Kentucky University (WKU) offered a course entitled Biochemistry for the Health Sciences in the spring semester of 2007. The course was taught in Interactive Television (ITV) format, and was the first time a class had been taught in the format enabling two-way communication by the Chemistry Department. One section was present in an ITV broadcast classroom on the main campus in Bowling Green, Kentucky. Another section received the broadcast on the campus of Western Kentucky University-Owensboro (WKU-O), at Owensboro Community and Technical College (OCTC), located in Owensboro, Kentucky. The purpose of this thesis is to evaluate the delivery of …

Carbon Dioxide Capture: Using Activated Carbon From Chicken Waste, Yan Zhang

Masters Theses & Specialist Projects

Carbon Dioxide (CO2) emission from hydrocarbon fuel combustion is becoming a serious concern because it is the main contributor to greenhouse gas which causes global warming. Activated carbon sorbents have been used widely in various gas-phase and/or liquid-phase separation. Currently activated carbon (AC) is being investigated and developed for CO2 capture. Chicken waste, which is produced in large quantity in U.S., is currently disposed as waste. However, it may have a large benefit to turn chicken waste into useful activated carbon. In this research, a series of activated carbon have been generated from chicken waste and coal in the lab …

Ua66 2007 Student Awards Ceremony, Wku Ogden College Of Science & Engineering

WKU Administration Documents

Program recognizing Ogden College students with brief list of activities for each student.

Pseudostationary Phase For Solid Phase Extraction, Qing Zhao

Masters Theses & Specialist Projects

A unique pseudostationary phase for Solid Phase Extraction is presented. This pseudostationary phase consists of surfactant, which is initially immobilized onto hydrophilic cation exchange resin. The surfactant chain through hydrophobic interactions extracts hydrophobic analytes in the same manner as conventional bonded alkyl moieties on silica based non-polar sorbents. Although hydrophobic analytes can be efficiently trapped on commercially available non-polar sorbents (i.e. Ci8 silica), organic solvents that are necessary to break strong hydrophobic interactions between the analytes and the sorbent are harmful. They are also incompatible for direct introduction into a reversed phase liquid chromatographic set up. In the presented approach, …

Spectroscopic Studies Of Inclusion Host-Guest Complexes Between Cyclophane Corrals And Polcyclic Aromatic Hydrocarbons, Mark O'Brien

Masters Theses & Specialist Projects

Cyclophanes are macromolecules that are known to effectively bind with molecules to form host-guest complexes. Several cyclophane molecules, referred to as corrals (1-6) by their founders, have been synthesized. The characterization of these compounds and their complexes has been investigated using combined spectroscopic and theoretical methods. Hostguest interactions of cyclophane-anthracene (C-A), cyclophane-9-fluorenone (C-F) and cyclophane-pyrene (C-P) complex systems in dichloromethane are presented in this thesis. The stability constants, log Ka, for the C-A, C-F and C-P complexes are determined using absorption and fluorescence spectroscopy. Heats of formation of corral 2 complexes were determined by measuring the complex association constants at …

Synthesis And Characterization Of Polyaminopolycarboxylic Acid Analogs Of Edta And Their Transition Metal Complexes, Martha Watson

Masters Theses & Specialist Projects

Polyaminopolycarboxylic acids have been studied for their ability to complex with various transition metal ions. Polyaminopolycarboxylic acids are of particular interest due to their ability to form multiple chelate rings with transition metal ions. Three analogs of EDTA have been successfully synthesized and characterized by i3C NMR: 1,3 PDTA (1,3-propylenediaminetetraacetic acid), 1,3-PDTP (1,3-propylenediaminetetrapropionic acid) and EDTP (ethylenediaminetetrapropionic acid). These ligands were then combined with copper (II), iron (III), cobalt (II) and nickel (II) to form complexes. The complexes formed were analyzed using UV-Vis, and the stability constants of the complexes were determined using potentiometry.

Determination Of Atrazine And Selected Respective Metabolites Using Strong Cation Exchange Resins, Cierra Cross

Masters Theses & Specialist Projects

A new solid phase extraction procedure (SPE) for the removal of atrazine and three respective metabolites including deisopropylatrazine, desethylatrazine, and didealkylatrazine from aqueous samples is presented. Octadecyl bonded silica (C18) is widely used in analytical preconcentration schemes. While C18 presents a facile method of analyte removal, a new approach is needed to achieve greater trapping for polar analytes. In this study strong cationic exchange (SCX) resins consisting of sulfonated polystyrene are investigated for their extraction capabilities of the selected analytes. By exploiting acid-base and pi-pi interactions the analytes are trapped and therefore extracted from aqueous samples. Salt solutions are used …

Carbon-Carbon Bond Formation Via O-Lithiointermediates, Julia Raymer

Masters Theses & Specialist Projects

The process of C-C bond formation via Directed ort/zo-Metalation (DoM) consists of two separate steps. Utilizing fractional equivalents of TMEDA in hydrocarbon solvents at 60°C, o-lithiation of anisole and dimethylaniline can be effected in >95% yields. The first step in the DoM process involves preparation of solid samples of these o-lithiointermediates. Completing the sequence, the second step concerns formation of a new arene-derivative bond at the reactive site. For this thesis the arene-derivative bond formed is to carbon. Various carbon electrophiles have been studied using different solvent systems, and results reveal a possible disconnect between the reaction conditions for the …

Cesium Effect: A Mild And Efficient Synthesis Of Secondary And Tertiary Phosphines, Matthew Honaker

Masters Theses & Specialist Projects

A mild and efficient method to synthesize a variety of secondary and tertiary, as well as disecondary and ditertiary phosphines has been developed. Using reaction conditions that include cesium hydroxide, molecular sieves, and DMF, at room temperature, a wide range of alkyl halides has been coupled to primary or secondary phosphines to yield secondary or tertiary phosphines. Included were activated and aliphatic halides, as well as base sensitive functional groups. In addition, examples of disecondary and ditertiary ligands have also been prepared using similar reaction conditions. The synthesis of a P-N-P ligand was also accomplished with these procedures. Optically active …

Directed Ortho Metalation In Hydrocarbon Solvents: Opposing Pi-Resonance Effects, Barry Woosley

Masters Theses & Specialist Projects

Hydrocarbon solvents are known to be unreactive toward organolithium reagents and do not typically support ortho-metalation reactions without the aid of a promoter. An exception would be an arene substrate having the capability to bidentate complex to the reactive alkyllithium dimer, which enables ortho-metalation to occur in high yields. A second, more limiting exception, would be that the arene substrate possesses localized lone pairs of electrons, as is the case when the directed ortho metalating group (DMG) is located in the benzyl position. The work reported here centers upon developing a third and larger class of arene substrates that are …

Spectroscopic Studies Of Chlorophyll A Complexes With Trinitro-Substituted Flourene Derivatives, Stephanie Smalley

Masters Theses & Specialist Projects

Absorption, fluorescence, and excited-state lifetime studies of chlorophyll a (Chl a) with fluorene, 2-(2,4,7-Trinitro-fluoren-9-ylideneaminooxy)-propionic acid (TFPR), 2- (2,4,7-Trinitro-fluoren-9-ylidenemethyl)-phenol, (TFPH), and 9-Isopropylidene-2,4,7- trinitro-9H-fluorene (ITNF) have been investigated. These systems were studied in acetonitrile and dichloromethane at room temperature. Absorption data were analyzed with the Nash plot. Linearity of the Nash plots proved that a 1:1 complex was formed between the donor and acceptor. Ground state binding constants (Ka) of each system were also determined from the y-intercept of these plots. Fluorescence data were analyzed with a Stern-Volmer plot. The quenching constants (Ksv) were obtained from the slope of these plots. These …

Determination Of Carbon Nanotube Modification By Tg-Ms And Pyrolysis-Gc/Ms, Quentin Lineberry

Masters Theses & Specialist Projects

Uniform dispersion of carbon nanotubes (CNTs) has been one of the major impediments to the full development of the incredible suite of properties offered by CNTs, specifically single-walled carbon nanotubes (SWNTs). However, investigators at NASA Langley and the National Institute of Aerospace Research have recently obtained (SWNTs) that are soluble in select solvents, including THF, DM Ac, and ODCB. The SWNTs were exposed to reagents used in cited fullerene modification chemistry in an attempt to produce soluble SWNTs. Upon further examination, it was determined that the intended functionalization had not occurred, and some other phenomenon was responsible for the SWNTs …

Development Of A Gene Transfer System In Clostridium Scindens Vpi 12708, Rashmi Ramasubbaiah

Masters Theses & Specialist Projects

Clostridium scindens VPI 12708 (previously known as Eubacterium sp. VPI 12708) is a bile-acid dehydroxylating bacterium originally isolated from the feces of a colon cancer patient. Many genes required for bile acid 7-a dehydroxylation are found on a large bile acid inducible operon (bai) that has been extensively studied. However the bai promoter, which directs expression of the bai operon, has yet to be characterized due, in part, to a lack of a functional genetic transfer system for this strain. A spontaneous rifampinresistant Clostridium scindens VPI 12708 mutant was used as a recipient to determine the efficacy of conjugation as …

Development Of An Analytical Method For Distinguishing Ammonium Bicarbonate From The Products Of An Aqueous Ammonia Co2 Scrubber And The Characterization Of Ammonium Bicarbonate, Lingyu Meng

Masters Theses & Specialist Projects

The link between anthropogenic emissions of CO2 with increased atmospheric CO2 levels and, in turn, with increased global temperature has been well established and accepted. Using aqueous ammonia to capture CO2 and produce an inexpensive nitrogen fertilizer, ammonium bicarbonate (ABC) has been thought as a feasible approach to CO2 sequestration.

Due to the different concentrations of reactants and reaction conditions, different carbon-ammonium composites can be produced. In view of achieving a maximum of NH3 utilization in the capture of CO2, the product of ABC will be ideal. Hence the ABC in the products needs to be identified. Various analytical techniques …

Silica Based Solid Phase Extraction Sorbent With A Removable Alkyltrimethylammonium Surfactant Phase, Tony Oakes

Masters Theses & Specialist Projects

Presented is a solid phase extraction (SPE) sorbent having a removable "stationary phase." This removable phase that consists of alkyltrimethylammonium surfactant is initially immobilized onto hydrophilic strong cation exchange resin. The surfactant chain through hydrophobic interactions extracts hydrophobic analytes in the same manner as conventional bonded alkyl moieties on silica based non-polar sorbents. For the extraction of very hydrophobic species with conventional sorbents, solvents used for analyte elution are generally toxic and not directly instrument compatible. The chosen solvent must be strong enough to efficiently break hydrophobic interactions between the analyte and sorbent. Using a removable "stationary phase," hydrophobic interactions …

Investigation Of The Relationship Between Particulate Bound Mercury And Properties Of Fly Ash In A Full-Scale 100 Mwe Pulverized Coal Combustion Boiler, Sen Li

Masters Theses & Specialist Projects

There is an increasing concern over mercury emissions from coal-fired boilers. Coal-fired power generation accounts for approximately 33% of total mercury emission in the United States. Once it is emitted into the atmosphere and deposited on land or water, mercury can transform into methylmercury, an organic form. Mercury can then enter the food chain, which poses a potential threat to human health and the environment. To study the relationship between particulate bound mercury and fly ash properties, fly ash samples were collected from the mechanical hopper (MHP) and the electrostatic precipitator (ESP) of a 100 MWe pulverized coal-fired boiler and …

Direct Multielemental Analysis Of Solid Samples Using Laser Ablation Inductively Coupled Plasma Mass Spectometry And Pulsed Radio Frequency Glow Discharge Mass Spectrometry, Joseph Miller

Masters Theses & Specialist Projects

Direct solid sampling is an area of analytical research that has generated a large amount of interest in recent years. Two analysis systems offering fast and nondestructive methods of determining the elemental composition of substances, without requiring complicated sample preparation procedures, are laser ablation inductively coupled plasma mass spectroscopy (LA-ICPMS) and radio frequency glow discharge mass spectroscopy (rf-GDMS). A Cetac LSX-200 laser system coupled to a LECO Renaissance ICPMS was utilized to analyze coal and ash samples prepared by incorporation into a lithium borate matrix to form a disk. In addition, a VG 9000 Glow Discharge Mass Spectrometer (GDMS) with …

A 59-Cobalt Nmr Investigation Of The Hydrogen/Deuterium Exchange Kinetics In Cobalt(Iii) Complexes, Michelle Mccombs

Masters Theses & Specialist Projects

Currently, the hydrogen/deuterium exchange kinetics in cobalt(III) complexes are being investigated. In the presence of deuterated solvents, (e.g. D2 0 and CH3CH20D) the amine hydrogens in the complexes are exchanged for deuteriums. For the hexaamminecobalt(III) ion, 19 isotopmers (H18D0 to HOD 18) are possible. For the tris(ethylenediammine)cobalt(III) ion, 13 isotopmers (HI 2D0 to HOD 12) are possible. Each hydrogen/deuteruim exchange causes a shift in the observed 59Co resonance of approximately 6 ppm. The rate constant of the hydrogen-deuterium exchange for the first H-D exchange has been determined as a function of solvent. When the chosen solvent is D20, the rate …

Teachers' Resource For Materials And Environmental Chemistry, Carnetta Skipworth

Masters Theses & Specialist Projects

In many secondary education chemistry classrooms, teachers have a difficult time introducing chemistry topics in a way that will be interesting to the high school student. The development of a materials and environmental chemistry teacher's manual will help teachers introduce a variety of selected topics in an interesting fashion to the students. This manual focuses on the subjects covered for freshman and sophomore level students. The manual uses five separate experiments to introduce topics such as the electromagnetic spectrum and solubility. The five experiments include a test on tennis shoe stiffness and energy dissipation ability, pesticides in water, grease in …

Directed Ortho-Metalation Of Dimethylarylamines, Michael Timmons

Masters Theses & Specialist Projects

Site-specific product(s) from the reaction of benzene derivatives with various reagents is a need of researchers at numerous laboratories, particularly those in the pharmaceutical industry. Such derivatives can be synthesized directly, i.e., by substitution of a proton, using either of two procedures: electrophilic aromatic substitution (EAS) or directed ortho-metalation (DoM). Directed ortho-metalation (DoM) is an alternative aromatic substitution process initiated by organolithium reagents which provides regiospecific substitution exclusively at the ortho- position (equation). The focus of this study is to find hydrocarbon media that will permit the maximum extent of metalation of several dimethylarylamines. The dimethylamine-containing substituents constitute directing metalation …

Metalation Of The Di- And Tri-Methoxybenzenes, Phillip Shelton

Masters Theses & Specialist Projects

Hydrocarbon solvents are known to be unreactive towards organolithium reagents and also to afford little support for ortho-metalation reactions. In contrast, both m- and odimethoxybenzene afford 80% "ion-multiple specific" monometalation in hydrocarbon solvent (n-hexane, cyclohexane, toluene) without the addition of any catalyst (ether or amine). These observations are, in part, attributed to the 1,2- and 1,3- formation of the n-BuLi dimer, the most reactive form of n-BuLi. In other words these substrates are acting in a "substrate-catalyzed" manner. Extensions of these concepts to 1,2,3-, 1,2,4- and 1,3,5-trimethoxybenzenes have led to further unusual observations. In particular, the 1,2,3-system affords an interesting …

Ua66/7/2 Hilltopper News, Wku Chemistry

WKU Administration Documents

Newsletter created by and about the WKU Chemistry department.

Study Of Polyaromatic Hydrocarbons Emitted In The Fly Ash From Coal Combustion In A Fluidized Bed Combuster, Rebecca Heltsley

Masters Theses & Specialist Projects

Exposure to Polyaromatic Hydrocarbons (PAHs) has long been identified as an environmental concern because of their carcinogenic and mutagenic effects. The Environmental Protection Agency (EPA) has developed a list of 16 PAHs that are found on the Priority Pollutant List due to the extensive amount of data suggesting the hazards of these compounds. These toxic compounds are often emitted into the atmosphere by anthropogenic sources, such as combustors. Therefore, analysis of these compounds must be conducted during coal combustion. Two 1000-hour coal combustion burns were performed using the 0.1 MWth bench-scale fluidized bed combustor (FBC), which is found in the …

Development Of Bismaleimide/Cyanate Ester Based Aerospace Polymers For Possible Use In Nasa's Relaunchable Vehicles Program, Brian Sisk

Masters Theses & Specialist Projects

Since the beginning of the space age, the goal of materials development in the aerospace industry has been to replace metal alloys with much lighter polymer resins, while maintaining the strength over a wide temperature range characteristic of metals. Polymers such as polyimides and epoxies have been used to satisfy many needs, but strength, temperature resistance, and ease of processing are difficult to incorporate into a single polymer. Because of this gap, bismaleimides and cyanate esters, and possibly combinations of the two, are seen as having potential in applications where ease of processing characteristic of epoxies is desired, but for …

Studies Of Sulfur Reduction Of Taurine And Taurine-Conjugated Bile Acids By Bile Acid 7Α-Dehydroxylating Bacteria, Jiang Qian

Masters Theses & Specialist Projects

Bile acids are C24 steroids that are derived in the liver from cholesterol and secreted into the intestinal lumen to aid in emulsification of dietary lipids and lipid-soluble vitamins. The indigenous intestinal microflora modify bile acids, producing up to 20 unique bile acid metabolites. The 7α-dehydroxylation of the bile acids is the most physiologically important bile acid biotransformation. All known intestinal bacteria capable of bile acid 7α-dehydroxylation are anaerobic, gram-positive rods of the genera Clostridium and Eubcicterium. Bile acid 7α-dehydroxylating bacteria often contain bile salt hydrolase, which hydrolyzes the peptide bond in taurine-conjugated bile acids to yield a free bile …

Enantioseparation Of Alkylaryl Sulfoxides Using Capillary Zone Electrophoresis, Chad Snyder

Masters Theses & Specialist Projects

Alkylaryl sulfoxides possess a chiral sulfur atom easily identifiable by capillary zone electrophoresis (CZE). Separation of chiral alkylaryl sulfoxides has already been accomplished by modified method of CZE known as micellar electrokinetic chromatography (MEKC). However, no articles have been published on the enantioseparation of alkylaryl sulfoxides using capillary zone electrophoresis.

A series of sulfoxides were synthesized, purified and identified via NMR. Enantioseparation was performed using CZE employing a 10 mmol. Phosphate buffer (pH 4.0, 25% acetonitrile, 2% sulfated-β-cyclodextrin). Synthesis of these sulfoxides will be presented along with the results of the procedure’s optimization. Separation of the sulfoxide enanitomers relies on …