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Analysis of Acid Gas Emissions in the Combustion of the Binder Enhanced d-RDF by Ion Chromatography

Description: Waste-to-energy has become an attractive alternative to landfills. One concern in this development is the release of pollutants in the combustion process. The binder enhanced d-RDF pellets satisfy the requirements of environmental acceptance, chemical/biological stability, and being storeable. The acid gas emissions of combusting d-RDF pellets with sulfur-rich coal were analyzed by ion chromatography and decreased when d-RDF pellets were utilized. The results imply the possibility of using d-RDF pellets to substitute for sulfur-rich coal as fuel, and also substantiate the effectiveness of a binder, calcium hydroxide, in decreasing emissions of SOx. In order to perform the analysis of the combustion sample, sampling and sample pretreatment methods prior to the IC analysis and the first derivative detection mode in IC are investigated as well. At least two trapping reagents are necessary for collecting acid gases: one for hydrogen halides, and the other for NOx and SOx. Factors affecting the absorption of acid gases are studied, and the strength of an oxidizing agent is the main factor affecting the collection of NOx and SOx. The absorption preference series of acid gases are determined and the absorption models of acid gases in trapping reagents are derived from the analytical results. To prevent the back-flushing of trapping reagents between impingers when leak-checking, a design for the sampling train is suggested, which can be adopted in sample collections. Several reducing agents are studied for pretreating the sample collected in alkali-permanganate media. Besides the recommendation of the hydrogen peroxide solution in EPA method, methanol and formic acid are worth considering as alternate reducing agents in the pretreatment of alkaline-permanganate media prior to IC analysis. The first derivative conductivity detection mode is developed and used in IC system. It is efficient for the detection and quantification of overlapping peaks as well as being applicable for non-overlapping ...
Date: August 1988
Creator: Jen, Jen-Fon

The Analysis of Fire Debris Using Nuclear Magnetic Resonance Spectroscopy

Description: This paper describes a new technique for analyzing fire debris using nuclear magnetic resonance (NMR) spectroscopy. Petroleum distillates, which are commonly used accelerants, were weathered, burned, and steamdistilled. These, as well as virgin samples of the accelerants, were analyzed by gas chromatography and nuclear magnetic resonance spectroscopy. In addition, solvent studies and detectibility limit studies were conducted. The use of NMR is described as a valuable adjunct to the existing methods of analysis.
Date: August 1981
Creator: Bryce, Kenneth L.

An Analysis of the Effectiveness of Computer Assisted Instruction in General Chemistry at an Urban University.

Description: The science-major General Chemistry sequence offered at the University of Houston has been investigated with respect to the effectiveness of recent incorporation of various levels of computer technology. As part of this investigation, questionnaire responses, student evaluations and grade averages and distributions from up to the last ten years have been analyzed and compared. Increased use of web-based material is both popular and effective, particularly with respect to providing extra information and supplemental questions. Instructor contact via e-mail is also well-received. Both uses of technology should be encouraged. In contrast, electronic classroom presentation is less popular. While initial use may lead to improved grades and retention, these levels decrease quickly, possibly due to a reduction in instructor spontaneity.
Date: May 2002
Creator: McGuffey, Angela

Applications of Nanomanipulation Coupled to Nanospray Mass Spectrometry in Trace Fiber Analysis and Cellular Lipid Analysis.

Description: The novel instrumentation of nanomanipulation coupled to nanospray mass spectrometry and its applications are presented. The nanomanipulator has the resolution of 10nm step sizes allowing for specific fine movement used to probe and characterize objects of interest. Nanospray mass spectrometry only needs a minimum sample volume of 300nl and a minimum sample size of 300attograms to analyze an analyte making it the ideal instrument to couple to nanomanipulation. The nanomanipulator is mounted to an inverted microscope and consists of 4 nano-positioners; these nano-positioners hold end-effectors and other tools used for manipulation. This original coupling has been used to enhance the current abilities of cellular probing and trace fiber analysis. Experiments have been performed to demonstrate the functionality of this instrument and its capabilities. Histidine and caffeine have been sampled directly from single fibers and analyzed. Lipid bodies from cotton seeds have been sampled indirectly and analyzed. The few applications demonstrated are only the beginning of nanomanipulation coupled to nanospray mass spectrometry and the possible applications are numerous especially with the ability to design and fabricate new end-effectors with unique abilities. Future study will be done to further the applications in direct cellular probing including toxicology studies and organelle analysis of single cells. Further studies will be directed in forensic applications of this instrument including gunshot residue sampled from fibers.
Date: December 2008
Creator: Ledbetter, Nicole

Applications of Single Reference Methods to Multi-Reference Problems

Description: Density functional theory is an efficient and useful method of solving single-reference computational chemistry problems, however it struggles with multi-reference systems. Modifications have been developed in order to improve the capabilities of density functional theory. In this work, density functional theory has been successfully applied to solve multi-reference systems with large amounts of non-dynamical correlation by use of modifications. It has also been successfully applied for geometry optimizations for lanthanide trifluorides.
Date: May 2015
Creator: Jeffrey, Chris C.

An Approach Towards the Total Synthesis of Clonostachydiol

Description: The syntheses of the unsymmetrical 14-membered bismacrolides have been reviewed. A total synthesis of clonostachydiol, the latest to join this family, has been attempted using trimethylsilyl acetylene as the builiding block and palladium catalyzed reactions for the formation of key bonds. The alkyne groups were introduced by Stille coupling of trimethylstannylethynyltrimethylsilane with an acid chloride for one fragment and by addition of lithiotrimethylsilyl acetylene to an aldehyde for the other. Lactic acid derivatives were chosen as starting materials for both fragments, thus introducing two of the chiral centers. The remaining stereocenters were introduced using stereoselective reductions of ketones.
Date: August 1995
Creator: Maiti, Tushar B. (Tushar Baran)

Aromatic Amino Acid Studies

Description: Pyridine ring analogs of the aromatic amino acids phenylalanine and tyrosine were synthesized and studied in microbiological and mammalian systems.
Date: December 1970
Creator: Sullivan, Patrick Timothy

Baeyer-Villiger Oxidation of 1,7- & 1,9-dibromopentacyclo[,6.03,10.05,9]undecane-8,11-dione

Description: Baeyer-Villiger oxidation of 1,9-dibromopentacyclo[,6.03,10.05,9]undecane-8,11-dione (1,9-dibromo-PCU-8,11-dione) was performed by using an excess amount of m-chloroperbenzoic acid (3 equivalents) and resulted in the formation of the corresponding monolactone. The reaction would not proceed to the dilactone stage. The structure of the reaction product was established unequivocally via single crystal X-ray diffraction. Baeyer-Villiger oxidation of 1,9-dibromo-PCU-8,11-dione using ceric ammonium nitrate (CAN) was also performed and afforded a mixture of lactones. Only one of these lactones, which also contained an alkene functionality, could be isolated and characterized. 1,7-dibromo-PCU-8,11-dione was also reacted with CAN, yielding the mono-lactone, which has also been characterized.
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Date: May 2004
Creator: Akinola, Adeniyi O.

Barbituric Acids. VII. 5-alkyl-derivatives of 5-ethoxy-barbituric Acid

Description: A great deal of research has been devoted in recent years to the search for new drugs for the treatment of epilepsy and related convulsive disorders. This emphasis is occasioned by the fact that no one drug is effective for all patients, and also by the fact that the toxicity of a drug varies considerably from one patient to another. Among the most effective drugs are certain members of the hydantoin and barbituric acid series. For some time there has been in progress in this laboratory an investigation of members of these two series in which a hetro atom attached directly to the hetrocyclic nucleus is introduced into the side chain at position five of these two series.
Date: January 1955
Creator: Hyde, Harold Wayne

Barbituric Acids. VIII. 5-substituted-5-(1-pyrrolidyl)barbituric Acids

Description: The purpose of this investigation then was the preparation of a series of 5-substituted-5-(1-pyrrolidyl)barbituric acids in which R would consist of alkyl groups ranging in size from methyl to amyl, and other groups such as phenyl and benzyl. These compounds are to be tested elsewhere for hypnotic and anticonvulsant activity.
Date: 1957
Creator: Compton, Ross Davis

Barbituric Acids. V. 5-substituted-mercapto Derivatives of 5-isoamylbarbituric Acid

Description: Since no mention has been found in the literature of any 5-substituted mercapto-5-alkyl derivatives of barbituric acid, it was thought to be of interest to prepare a series of compounds containing sulfur attached directly to the barbituric acid nucleus. 5-substituted mercapto-5-isoamylbarbituric acids were chosen as representative of barbituric acids in which the alkyl group has a fairly high molecular weight.
Date: August 1952
Creator: Peterson, Paul Eugene

Biological Inhibitors

Description: Four isosteric series of plant growth-regulating compounds were prepared. Using an Avena sativa coleptile assay system, derivatives in series I and IV inhibited segment elongation to a greater degree than did comparable derivatives in series II and III.
Date: December 1971
Creator: Sargent, Dale Roger

Bis Ammonium Salts of Dialkylaminoalkoxypropionitriles

Description: This paper concerns the preparation of some bis derivatives of dialkylaminoalkoxypropionitirles from trimethylene, hexamethylene, octomethylene, and decamethylene bromides. These compounds are to be tested for curariform activity and anesthetic values by Parke, Davis and Company.
Date: August 1957
Creator: Woods, Roy Jack

Bonding Studies in Group IV Substituted n,n-dimethylanilines

Description: The purpose of the present work is to study the effects of the trimethylsilyl and trimethylgermyl substituents on the N,N-dimethylamino ring system. Both ground and excited state interactions were studied and their magnitudes determined. The experimental data were then used in conjunction with molecular orbital calculations to differentiate among, and determine the importance of, d-p bonding, hyperconjugation or polarization of the trimethylsilyl group on the ground and excited state bonding.
Date: December 1971
Creator: Drews, Michael James