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A Study Of Combustion Profiles Of Co-Fired Coal/Biomass/Limestone Samples In A Fluidized Bed Combustor, Beverly Campbell May 1997

A Study Of Combustion Profiles Of Co-Fired Coal/Biomass/Limestone Samples In A Fluidized Bed Combustor, Beverly Campbell

Masters Theses & Specialist Projects

Concerns over declining landfill space and a renewed interest in waste-toenergy technologies have increased the possibilities of co-firing different types of fuels in atmospheric fluidized bed combustion systems. The laboratory sized atmospheric fluidized bed combustor (AFBC) at Western Kentucky University was designed to serve as a highly flexible research and development facility to gain operating experience, evaluate combustion performance, and estimate the effect of flue gas emissions on the atmosphere. The operating conditions for the AFBC system are similar to those used at the TVA 160-MW AFBC Pilot Plant located near Paducah, Kentucky. AFBC systems are ideal for co-firing because …


Thermal Decomposition Reactions Of Acetaldehyde And Acetone On Si(100), J.L. Armstrong, J.M. White, Marjorie Langell May 1997

Thermal Decomposition Reactions Of Acetaldehyde And Acetone On Si(100), J.L. Armstrong, J.M. White, Marjorie Langell

Marjorie A. Langell Publications

We have studied the thermal interactions of acetone and acetaldehyde on Si(100), both sputtered and annealed, using high resolution electron energy loss spectroscopy, (HREELS), x-ray photoelectron spectroscopy (XPS), and temperature programmed desorption (TPD). There is no carbonyl stretch in HREELS and the C and O(1s) XPS peaks reflect two different carbonyl processes, one involving bond cleavage, the other a reduction of the C–O bond order. Hydrogen TPD gives a peak at 840–850 K which is as much as threefold more intense than from H-saturated Si(100). SiO desorbs near 1050 K and XPS shows total loss of oxygen and …


Synthesis And Protection Of Nitrogen Containing Heterocycles, Timothy I. Elwell May 1997

Synthesis And Protection Of Nitrogen Containing Heterocycles, Timothy I. Elwell

Undergraduate Honors Capstone Projects

The pyrrolo[2,3-d] pyrimidine ring systems are present in a variety of antibacterial/anticancer compounds. A scarcity of natural sources has made necessary the need for researchers to find more efficient methodologies to synthesize such compounds.1 The Edstrom research group is currently exploring new routes to these compounds, varying the protecting groups and the precursors used to make them.


Mass Balance Of Major, Minor And Trace Elements During Afbc Combustion Of Fuels, Qianwen Cao May 1997

Mass Balance Of Major, Minor And Trace Elements During Afbc Combustion Of Fuels, Qianwen Cao

Masters Theses & Specialist Projects

The proposed ASTM procedures for the determination of 13 major and minor., and 11 trace elements, in solid coal and coke combustion residues by inductively coupled plasma-atomic emission spectrometry (ICP-AES) were checked for routine use. In this study, the ICP analysis values and XRF analysis values of major and minor elements in two kinds of coal and two kinds of limestone were compared. It was shown that over 95% closure of the mass balances of the 24 major, minor, and trace elements was obtained with the proposed ASTM procedure. Also, it was demonstrated that trace elements may be lost through …


Binding Of Cobalt (Iii) To Nucleic Acids Via Reaction With [Co(Nh3)5(Oh2)]3+, David M. Calderone May 1997

Binding Of Cobalt (Iii) To Nucleic Acids Via Reaction With [Co(Nh3)5(Oh2)]3+, David M. Calderone

Seton Hall University Dissertations and Theses (ETDs)

No abstract provided.


In Situ Observations Of Air Traffic Emission Signatures In The North Atlantic Flight Corridor, Hans Schlager, Paul Konopka, P. Schulte, U. Schumann, H. Ziereis, F. Arnold, M. Klemm, Donald E. Hagen, Philip D. Whitefield, J. Ovarlez May 1997

In Situ Observations Of Air Traffic Emission Signatures In The North Atlantic Flight Corridor, Hans Schlager, Paul Konopka, P. Schulte, U. Schumann, H. Ziereis, F. Arnold, M. Klemm, Donald E. Hagen, Philip D. Whitefield, J. Ovarlez

Physics Faculty Research & Creative Works

Focussed aircraft measurements have been carried out over the eastern North Atlantic to search for signals of air traffic emissions in the flight corridor region. Observations include NO, NO2, HNO3, SO2, O3, H2O, total condensation nuclei (CN), and meteorological parameters. A flight pattern with constant-altitude north-south legs across the major North Atlantic air traffic tracks was flown. Signatures of air traffic emissions were clearly detected for NOx, SO2, and CN with peak concentrations of 2 ppbv, 0.25 ppbv, and 500 cm-3, respectively, exceeding background …


Computer Modeling Of Molecular Vibration Frequencies And Its Application To The Modeling Of Silane Compounds, Ryan T. Merrell May 1997

Computer Modeling Of Molecular Vibration Frequencies And Its Application To The Modeling Of Silane Compounds, Ryan T. Merrell

Honors Capstone Projects and Theses

No abstract provided.


Xenon Isotope Record Of Nucleosynthesis And The Early Solar System, Jauh-Tzuoh Lee, Bin Li, Oliver Manuel May 1997

Xenon Isotope Record Of Nucleosynthesis And The Early Solar System, Jauh-Tzuoh Lee, Bin Li, Oliver Manuel

Chemistry Faculty Research & Creative Works

No abstract provided.


Synthesis Of 1-Alloc-Piperidine-4-Fmoc-Amino-4-Carboxylic Acid: A Novel, Protected ?,?- Disubstituted Amino Acid, Muna K. Thalji Apr 1997

Synthesis Of 1-Alloc-Piperidine-4-Fmoc-Amino-4-Carboxylic Acid: A Novel, Protected ?,?- Disubstituted Amino Acid, Muna K. Thalji

Honors Capstones

No abstract provided.


Magnetic And Structural Properties Of Nd₂Fe₁₇₋ₓmnₓ Solid Solutions, Peter C. Ezekwenna, G. K. Marasinghe, William Joseph James, Oran Allan Pringle, Gary J. Long, H. Luo, Z. Hu, William B. Yelon, Ph. I'Héritier Apr 1997

Magnetic And Structural Properties Of Nd₂Fe₁₇₋ₓmnₓ Solid Solutions, Peter C. Ezekwenna, G. K. Marasinghe, William Joseph James, Oran Allan Pringle, Gary J. Long, H. Luo, Z. Hu, William B. Yelon, Ph. I'Héritier

Chemistry Faculty Research & Creative Works

A series of Nd2Fe17-xMnx solid solutions with x values between 0 and and 6 were prepared and analyzed using magnetic measurements, neutron diffraction, and Mössbauer spectroscopy. All of the Nd2Fe17-xMnx samples crystallized in the Th2Zn17-x-type rhombohedral structure. The lattice parameters and unit cell volumes decrease with increasing manganese content up to ∼ x equal to 2, and then increase for higher manganese content. The magnetizations of Nd2Fe17-xMnx decrease with increasing manganese content and Nd2Fe17-xMnx is paramagnetic …


An Analysis Of Iron-Iron Interatomic Distances In Several Rare Earth Transition Metal Intermetallics, G. K. Marasinghe, Peter C. Ezekwenna, William Joseph James, Z. Hu, William B. Yelon Apr 1997

An Analysis Of Iron-Iron Interatomic Distances In Several Rare Earth Transition Metal Intermetallics, G. K. Marasinghe, Peter C. Ezekwenna, William Joseph James, Z. Hu, William B. Yelon

Chemistry Faculty Research & Creative Works

As a part of a systematic study of the dependence of iron-iron exchange interactions on near neighbor iron-iron distances in rare earth transition metal magnetic materials, we have conducted a statistical analysis of interatomic distances in Nd2Fe17, Nd2Fe17N3, and Nd2Fe14B. Results, in general, support the notion that larger near neighbor iron-iron distances promote higher Curie temperatures. In this work, special attention has been paid to the expansion of the Nd2Fe17 lattice due to interstitial nitrogenation and the accompanying increase in the Curie temperature. …


Studies Of V, Nb, Cr, And Zr Substituted 2:17 Compounds And Their Carbides Using Neutron Diffraction, H. Luo, Z. Hu, Muguo Chen, William B. Yelon, G. K. Marasinghe, Peter C. Ezekwenna, William Joseph James, W. C. Chang, S. H. Tsai Apr 1997

Studies Of V, Nb, Cr, And Zr Substituted 2:17 Compounds And Their Carbides Using Neutron Diffraction, H. Luo, Z. Hu, Muguo Chen, William B. Yelon, G. K. Marasinghe, Peter C. Ezekwenna, William Joseph James, W. C. Chang, S. H. Tsai

Physics Faculty Research & Creative Works

Samples of Nd2Fe17-xTxCy with T=V, Nb, Cr, and Zr were prepared by melting of the constituent elements including C and studied by neutron diffraction. Comparing with their uncarbided counterparts, we found that the substituents transfer, more or less, from the 6c site to the 18f and 18h sites with the introduction of C atoms. This behavior appears to relate to the electronegativities between the C atoms and the early transition series elements because the 18f and 18h sites are near neighbors of the interstitial C site. However, the C effects in the V. …


Synthesis And Characterization Of Modified Silica Gel As An Intermediate In The Generation Of Gaseous Standard Mixtures, M. Prokopowicz, K. Lewandowska, A. Skwierawska, Andrzej Przyjazny, Jan F. Biernat, J. Namiesnik Apr 1997

Synthesis And Characterization Of Modified Silica Gel As An Intermediate In The Generation Of Gaseous Standard Mixtures, M. Prokopowicz, K. Lewandowska, A. Skwierawska, Andrzej Przyjazny, Jan F. Biernat, J. Namiesnik

Chemistry & Biochemistry Publications

A possibility of extending analytical applications of chemically modified silica gels is described. This involves their utilization for the generation of gaseous standard mixtures consisting of methyl chloride as the analyte and nitrogen as a carrier gas to be used for the calibration of the GC-FID system. N-methylmorpholine was chemically bonded to the propylsilylated surface of silica gel forming chloride of an appropriate immobilized compound which, under certain conditions, undergoes thermal decomposition yielding a single, volatile component (methyl chloride). Such a method of generating specific amounts of a standard substance can be used both for a single point calibration and …


Development Of A High-Speed Ultraviolet Spectrometer, Capable Of Real-Time No And Aromatic Hydrocarbon Detection In Vehicle Exhaust (Presentation), Peter J. Popp, Gary A. Bishop, Donald H. Stedman Apr 1997

Development Of A High-Speed Ultraviolet Spectrometer, Capable Of Real-Time No And Aromatic Hydrocarbon Detection In Vehicle Exhaust (Presentation), Peter J. Popp, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

Paper presented at the 7th Coordinating Research Council On-Road Vehicle Emissions Workshop, San Diego, CA, April 9-11, 1997.


Mechanistic Studies On The Aminopeptidase From Aeromonas Proteolytica:  A Two-Metal Ion Mechanism For Peptide Hydrolysis, Guanjing Chen, Tanya Edwards, Ventris M. D'Souza, Richard C. Holz Apr 1997

Mechanistic Studies On The Aminopeptidase From Aeromonas Proteolytica:  A Two-Metal Ion Mechanism For Peptide Hydrolysis, Guanjing Chen, Tanya Edwards, Ventris M. D'Souza, Richard C. Holz

Chemistry Faculty Research and Publications

The aminopeptidase from Aeromonas proteolytica (AAP) is uncompetitively inhibited by fluoride ion at pH 8.0 with an inhibition constant (Ki) of 30 mM. Thus, fluoride inactivates AAP only after substrate binding, and only a single fluoride ion binds to AAP. On the other hand, chloride ion does not inhibit AAP up to concentrations of 2 M at pH 8.0. The pH dependence of fluoride inhibition of AAP was measured over the pH range 6.0−9.5. Between pH values of 6.0 and 9.0, fluoride ion acts as a pure uncompetitive inhibitor of AAP, and the Ki increases from …


Dipole Spectroscopy, Ronald Lovett Apr 1997

Dipole Spectroscopy, Ronald Lovett

Topics in Quantum Mechanics

No abstract provided.


Rounding Numbers: Why The "New System" Doesn't Work, W. Robert Midden Apr 1997

Rounding Numbers: Why The "New System" Doesn't Work, W. Robert Midden

Chemistry Faculty Publications

This paper explains a correction to the rounding rule previously publishedin this Journal. The earlier article reported that the best way to roundnumbers is to always round up when the first digit dropped is 5. However,this will lead to accumulation of error when errors are averaged. Arounding strategy that leads to less error is to round up when 5 isfollowed by any nonzero digits, but to round even when 5 is followed byzeros or no other digits. By rounding the last kept digit to an evennumber, half the time the digit is increased and half the time it is keptthe …


Fragment Rotational Distributions From The Dissociation Of Nebr2: Experimental And Classical Trajectory Studies, Mehdi Nejad-Sattari , '95, Thomas Alex Stephenson Apr 1997

Fragment Rotational Distributions From The Dissociation Of Nebr2: Experimental And Classical Trajectory Studies, Mehdi Nejad-Sattari , '95, Thomas Alex Stephenson

Chemistry & Biochemistry Faculty Works

The Br-2 fragment rotational distributions that result from the vibrational predissociation of NeBr2 in the B electronic state have been measured for several initial vibrational levels. In each case, the rotational distributions extend to the effective energetic Limit determined by the amount of energy available (E(av1)) for disposal into the fragment rotational and translational degrees of freedom. Analysis of the data allows refinement of the NeBr2 dissociation energy; we find that D-0=70.0 +/- 1.1 cm(-1) for the X electronic state, v = 0. Both Delta v = - 1 and -2 dissociation events have been examined. For dissociation pathways with …


Development Of Solid Phase Microextraction Methods For Contraband Drugs, Vangielynn Cruz Tersol Apr 1997

Development Of Solid Phase Microextraction Methods For Contraband Drugs, Vangielynn Cruz Tersol

Chemistry & Biochemistry Theses & Dissertations

The objective of this study is to develop analytical methods for studying contraband drugs at nanogram levels and to demonstrate the utility of the methods. A method which combines solid phase microextraction with ion mobility spectrometry (SPME-IMS) was developed. The SPME-IMS method was used as a rapid screening tool in studying the chemistry of cocaine HCI, heroin HCI, and heroin freebase on surfaces. The total time for sample preparation, reaction, and analysis is approximately seven minutes. Another method that was developed is one that combines solid phase microextraction with gas chromatography (SPME-GC) for the quantitative analysis of cocaine freebase and …


Analysis Of Organic Nitrates In Artic Outflow, Deanna Elyea-Piper Apr 1997

Analysis Of Organic Nitrates In Artic Outflow, Deanna Elyea-Piper

Masters Theses

The Arctic Outflow Study (AOS) was a project funded by the National Science Foundation to assess the impact of tropospheric ozone concentrations by the measurement of oxidized nitrogen. Measurements of arctic outflow were made to assess the seasonal cycle of compounds in arctic air and the partitioning of NOy during transport to the North Atlantic region. These photochemically active compounds are elevated in the arctic during the winter and spring because of the lack of photochemical processes to destroy them.

Measurements of PAN, Alkyl nitrates, NOy, NO, NO2, CO, HNO3, O3, and particulate nitrate …


Thermal Studies Of Complex Formations Of First Row Transition Metals With Phenolic Compounds In Aqueous Solution, Nabil Adnan Amro Apr 1997

Thermal Studies Of Complex Formations Of First Row Transition Metals With Phenolic Compounds In Aqueous Solution, Nabil Adnan Amro

Masters Theses

The coordination chemistry of protocatechuic acid and catechols with the first row of transition metals was studied as a model for the more complicated natural humic substance.

The reaction between Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+ and the phenols, catechol and protocatechuic acid in aqueous solution was studied by the spectrophotometric method. The composition of the complexes formed was determined by continuous variation, iso-molar series and molar ratio methods. The presence of complexes with metal:ligand ratio of 1:1, 1:2 and 1:3 was established in the pH range 3 to …


On-Road Co, Hc, No And Opacity Measurements (Presentation), Donald H. Stedman, Gary A. Bishop, Phillip Aldrete Apr 1997

On-Road Co, Hc, No And Opacity Measurements (Presentation), Donald H. Stedman, Gary A. Bishop, Phillip Aldrete

Fuel Efficiency Automobile Test Publications

Paper presented at the 7th Coordinating Research Council On-Road Vehicle Emissions Workshop, San Diego, CA, Aril 9-11, 1997.


Development Of A Fluorescent Indicator For Inorganic Monochloramine, Xiaojun Dong Zou Apr 1997

Development Of A Fluorescent Indicator For Inorganic Monochloramine, Xiaojun Dong Zou

Chemistry & Biochemistry Theses & Dissertations

Current methods used to determine combined residual chlorine cannot distinguish between inorganic monochloramine (NH2Cl) and organic chloramines. Studies described in this thesis were carried out to develop a novel method of determining the concentration of inorganic monochloramine in aqueous solutions. Based on the observation that the reaction of 3-formyl-1-methylpyridinium chloride (3FMPCl) with NH2Cl produces a solution which is fluorescent, experiments were conducted to characterize the reaction and optimize the experimental conditions. Using the finalized protocol, NH2Cl measurements were made in the presence and absence of organic amines and compared with a commonly used N, …


Molecular Cloning And Functional Analysis Of Polyphosphoinositide-Dependent Phospholipase D, Pldβ, From Arabidopsis, Kirk Pappan, Wensheng Qin, Jim Dyer, Ling Zheng, Xuemin Wang Mar 1997

Molecular Cloning And Functional Analysis Of Polyphosphoinositide-Dependent Phospholipase D, Pldβ, From Arabidopsis, Kirk Pappan, Wensheng Qin, Jim Dyer, Ling Zheng, Xuemin Wang

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

A novel plant phospholipase D (PLD; EC 3.1.4.4) activity, which is dependent on phosphatidylinositol 4,5-bisphosphate (PIP2) and nanomolar concentrations of calcium, has been identified in Arabidopsis. This report describes the cloning, expression, and characterization of an Arabidopsis cDNA that encodes this PLD. We have designated names of PLDβ for this PIP2- dependent PLD and PLDα for the previously characterized PIP2-independent PLD that requires millimolar Ca2+ for optimal activity. The PLDβ cDNA contains an open reading frame of 2904 nucleotides coding for a 968-amino acid protein of 108,575 daltons. Expression of this PLDβ cDNA clone in Escherichia coli results in the …


An Electrical Resistivity Study Of Ce₂Fe₁₆.₈ And The Ce₂Fe₁₇₋ₓalₓ And Ce₂Fe₁₇₋ₓsiₓ Solid Solutions, Denis Vandormael, Fernande Grandjean, Hassan Bougrine, Marcel R. Ausloos, D. P. Middleton, K. H. J. Buschow, Gary J. Long Mar 1997

An Electrical Resistivity Study Of Ce₂Fe₁₆.₈ And The Ce₂Fe₁₇₋ₓalₓ And Ce₂Fe₁₇₋ₓsiₓ Solid Solutions, Denis Vandormael, Fernande Grandjean, Hassan Bougrine, Marcel R. Ausloos, D. P. Middleton, K. H. J. Buschow, Gary J. Long

Chemistry Faculty Research & Creative Works

Electrical resistivity measurements have been carried out between 20 and 300 K on Ce2Fe16.8, on the Ce2Fe17-xAlx. solid solutions, with x = 0.4, 1, 2, 5, 6, 8, and 9, and on the Ce2Fe17-xSix solid solutions, with x = 0.2, 0.4, 1, and 2, with the four probe method. The temperature dependence of the resistivity of Ce2Fe16.8 shows an inflection at 110 K, a feature which is also observed in the temperature dependence of the magnetization and is related to a magnetic …


Ac Electrochemical Thermal Method For Investigating The Entropy Change Of Electrochemical Reaction, Liangjun Dong, Jihua Zhuang, Zhiyu Jiang Feb 1997

Ac Electrochemical Thermal Method For Investigating The Entropy Change Of Electrochemical Reaction, Liangjun Dong, Jihua Zhuang, Zhiyu Jiang

Journal of Electrochemistry

An ac electrochemical thermal method was developed for measuring the entropy change of the electrochemical reaction. When an ac current i0 cosωt passed through an electrode in the solution, the heat produced at the surface consisted of several parts. The part varied with frequency ω was caused by the entropy change of the electrochemical reaction, so called the Peltier heat. It could be measured by using a pyroelectric PVDF film detector with a lock in amplifier. This method presents the advantage to inhibit the influence of the polarization heat and Joule heat. The entropy changes of electrochemical reactions in …


Study Of The Nature Of Formic Acid Adsorbates On Rough Pt And Its Interaction With Co, Xinhua Xia, Iwasita T., Vielstich W. Feb 1997

Study Of The Nature Of Formic Acid Adsorbates On Rough Pt And Its Interaction With Co, Xinhua Xia, Iwasita T., Vielstich W.

Journal of Electrochemistry

The nature of formic acid adsorbates formed on porous platinum electrode has been studied by in-situ infrared reflectance spectroscopic (FTIR) and differential electrochemical mass spectroscopic (DEMS) techniques. By carefully avoiding the contamination of the environment (i.e ., air) voltammetric experiments show that the oxidation of formic acid adsorbates depends on both adsorption potential and adsorption time. The online DEMS results show furthermore that the number of electrons necessary for the formation of one molecule of CO2 from adsorbed formic acid is independent of the adsorption potential. Its value of 2.2 demonstrates that the composition of formic acid adsorbates is …


Electrochemical Synthesis And Characterization Of Ba-Pb-O And Bi-Pb-O Oxides, Min Xie, Liangzhong Zhao, Cuiying Xu, Jinbiao Zhang Feb 1997

Electrochemical Synthesis And Characterization Of Ba-Pb-O And Bi-Pb-O Oxides, Min Xie, Liangzhong Zhao, Cuiying Xu, Jinbiao Zhang

Journal of Electrochemistry

Pb-based oxides Ba-Pb-O and Bi-Pb-O were synthesized from aqueous solutions by using electrochemical method. The resulting Ba-Pb-O and Bi-Pb-O were characterized using XPS, EDX and XRD. The results show that perovskite BaPb0.9O3 can be electrodeposited on the anode only from strong alkaline solution. In acid aqueous solution, conducting BiPb2Oz oxide is fromed on the anode. In these oxides the nominal valence of lead is +4.


Electrochemical Studies Of Spinel Limn2O4 Rechargeable Lithium Battery, Li Feng, Yuqin Chang, Lie Wu, Hong Li, Yibin San, Tianhong Lu Feb 1997

Electrochemical Studies Of Spinel Limn2O4 Rechargeable Lithium Battery, Li Feng, Yuqin Chang, Lie Wu, Hong Li, Yibin San, Tianhong Lu

Journal of Electrochemistry

The spinel Li intercalation compound LiMn2O4 was prepared and studied using ac impedance and cyclic voltammogram techniques. It was first discussed that the impedance behaviors of LiMn2O4 electrode varied as lithium ion was intercalated in or out the electrode with the help of fractal theory. The Li reversible behaviors in LiMn2O4 electrode were shown by the cyclic voltammogram results.


Study On The Hydrophilicity Of Nafion Membrane Surface, Yanbing Zu, Chuansin Cha Feb 1997

Study On The Hydrophilicity Of Nafion Membrane Surface, Yanbing Zu, Chuansin Cha

Journal of Electrochemistry

Due to its high chemical stability and ion selective permeability, Nafion membrane has been applied in many electrochemical systems. The surface hydrophilicity is one of the main factors affecting its performance. In this paper, the bound bubble method is introduced as a suitable way to measure the contact angles between Nafion membrane and various aqueous solutions. During the measurement, Nafion membrane is saturated with given electrolyt solution. The hysteresis of the contact angles observed in the measurement is attributed to the co existance of hydrophobic and hydrophilic domains at the membrane surface. The effect of the solution surface tension on …