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37th Rocky Mountain Conference On Analytical Chemistry Jul 1995

37th Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 37th annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-sponsored by the Colorado Section of the American Chemical Society and the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, July 23-27, 1995.


Environments Of The Four Tryptophans In The Extracellular Domain Of Human Tissue Factor: Comparison Of Results From Absorption And Fluorescence Difference Spectra Of Tryptophan Replacement Mutants With The Crystal Structure Of The Wild-Type Protein, C. A. Hasselbacher, E. Rusinova, R. Rusinova, R. A. Kohanski, W. Lam, A. Guha, J. Du, T. C. Lin, I. Polikarpov, C. W. G. Boys, Y. Nemerson, W. H. Konigsberg, J. B. A. Ross Jul 1995

Environments Of The Four Tryptophans In The Extracellular Domain Of Human Tissue Factor: Comparison Of Results From Absorption And Fluorescence Difference Spectra Of Tryptophan Replacement Mutants With The Crystal Structure Of The Wild-Type Protein, C. A. Hasselbacher, E. Rusinova, R. Rusinova, R. A. Kohanski, W. Lam, A. Guha, J. Du, T. C. Lin, I. Polikarpov, C. W. G. Boys, Y. Nemerson, W. H. Konigsberg, J. B. A. Ross

Chemistry and Biochemistry Faculty Publications

The local environments of the four tryptophan residues of the extracellular domain of human tissue factor (sTF) were assessed from difference absorption and fluorescence spectra. The difference spectra were derived by subtracting spectra from single Trp-to-Phe or Trp-to-Tyr replacement mutants from the corresponding spectrum of the wild-type protein. Each of the mutants was capable of enhancing the proteolytic activity of factor Vila showing that the mutations did not introduce major structural changes, although the mutants were more susceptible to denaturation by guanidinium chloride. The difference spectra indicate that the Trp residues are buried to different extents within the protein matrix. …


Transitions In Masculinity And Hemingway's Developed "Code", Daniel Polk May 1995

Transitions In Masculinity And Hemingway's Developed "Code", Daniel Polk

Honors Theses

The "Hemingway Code" is much more than two words that fit nicely together for a scholar's usage; the words signify a much deeper championing of masculinity, almost a haunting presence. For Ernest Hemingway living life every day, every moment with its fullest masculine fervor, became an obsession, a never-ending quest to be at one with the attitude of never complaining, never crying out, panicking, thinking too much, or regretting. To live a manly life in a series of tactical victories, performed with steadfast ritualistic mannerisms, is to embody masculinity, and therefore the "Hemingway Code."


Electrocrystallization Of Strongly Adherent Brushite Coatings On Prosthetic Alloys (Continuation), Jody G. Redepenning May 1995

Electrocrystallization Of Strongly Adherent Brushite Coatings On Prosthetic Alloys (Continuation), Jody G. Redepenning

Department of Chemistry: Faculty Publications

An electrolytic method for providing bone-emulating, phosphate coatings on prosthetic appliances. Such coatings serve to enhance bone furation after implantation of the appliances. The method of the invention is an electrolysis process wherein the appliance to be coated is immersed in a phosphate-containing electrolyte to serve as the cathode of the electrolysis process. When current is appIied to the electrolysis cell, the electrolyte solution, which includes calcium ions and dihydrogen phosphate ions, is caused to rapidly increase in (localized) pH proximate the cathode element. The localized pH increase creates a supersaturated local condition causing less soluble calcium phosphate salts to …


Dna Interstrand Crosslinking Efficiencies, Sequence Preferences, And Organic Syntheses Of Diepoxide Metabolites In Fixation, Sara Charnecki May 1995

Dna Interstrand Crosslinking Efficiencies, Sequence Preferences, And Organic Syntheses Of Diepoxide Metabolites In Fixation, Sara Charnecki

Honors Theses

Molecular Basis of Cancer: Cancer, a disease that has had a devastating and frightening impact on current society in the midst of a chemical revolution, represents a class of diseases comprising over 200 known types that affect various regions of the mammalian body (Farmer & Walker, 1985). This disease strikes randomly and is often diagnosed after the disease has progressed beyond present treatment capabilities. Cancer is the result of irregularities in growth, reproduction, and differentiation of cells due to pennanent flaws in genetic information. Mutations caused by environmental factors can be compounded over time to cause carcinomas of different tissues. …


Synthesis Of Nitrosyl Metallpoprphyrins, Thomas M. Braxton Jr. May 1995

Synthesis Of Nitrosyl Metallpoprphyrins, Thomas M. Braxton Jr.

McCabe Thesis Collection

Nitric oxide, NO, is a molecule with great versatility and importance. Made up of only a single atom of nitrogen and a single atom of oxygen, nitric oxide is perhaps one of the smallest paramagnetic molecules found in nature. The functions of NO in the body are not all known, but this molecule definitely plays a variety of roles. It is involved in the regulation of blood pressure, and it sometimes acts as a messenger for cells as well as a killer of them. It also is important in the defense of the body against foreign invaders. The significance of …


Studies Directed Toward Enantioselective Catalysis, Brian E. Jones May 1995

Studies Directed Toward Enantioselective Catalysis, Brian E. Jones

Open Access Master's Theses (through 2010)

Many organic molecules of modest size and complexity have chirality.That is, these molecules can exist in more than one stereoisomeric form.There is a strong desire to synthesize chiral compounds that exist in the form of a single stereoisomer.The method of synthesizing chiral compounds that was studied in our research employed a less than stoichiometric amount of chiral catalyst to both catalyze and control the stereochemical outcome of the reactions attempted.

A new chiral ligand was developed to be used as part of the chiral catalyst.This new ligand was used in the enantioselective Diels-Alder cycloaddition reaction and the enantioselective allylation reaction …


Iron-Dithiothreitol Dependent Production Of 8-Hydroxy-2'-Deoxyguanosine In Dna, David Allan Cook May 1995

Iron-Dithiothreitol Dependent Production Of 8-Hydroxy-2'-Deoxyguanosine In Dna, David Allan Cook

Undergraduate Honors Capstone Projects

Oxidative damage to DNA in a metal-thiol system was studied. Calf thymus DNA was incubated in an iron(IIl)-dithiothreitol system prepared in various buffers. Damage was measured by monitoring the production of 8-hydroxy-2'-deoxyguanosine. DNA oxidation was proportional to the concentration of dithiothreitol (DTT) in HEPES and tris(hydroxymethyl)aminomethane (Tris) buffers while it was only roughly related to DTT concentration in sodium chloride. Incubation in potassium phosphate buffer produced no damage. The results indicate that hydroxyl radicals may be generated by the iron-OTT system in HEPES, Tris, and sodium chloride, while in the phosphate buffer an iron phosphate complex may be formed which …


Primase Structure And Function, Mark A. Griep Apr 1995

Primase Structure And Function, Mark A. Griep

Department of Chemistry: Faculty Publications

Primase is the ssDNA-dependent RNA polymerase that synthesizes RNA primers during DNA replication. In common with all DNA and RNA polymerases, primase has structural and functional features involved in polymer elongation. As RNA polymerase, it has structural and functional features for initiating chain synthesis. As a primase, it has structural and functional features for initiating chain synthesis on ssDNA. Using amino acid sequence analysis the structure of Escherichia coli primase responsible for binding zinc, at least three magnesium, and DnaB helicase has been identified. One of the magnesium binding motifs resembles the “active magnesium” motif found in all DNA and …


Structural Characterization Of A Novel Inhibitor Of Hiv Reverse Transcriptase (Hiv Rt), Greggory Jon Woitte Apr 1995

Structural Characterization Of A Novel Inhibitor Of Hiv Reverse Transcriptase (Hiv Rt), Greggory Jon Woitte

Chemistry & Biochemistry Theses & Dissertations

Human immunodeficiency virus (HIV) infections have become a leading cause of death among young people in the United States today. As the number of HIV infections increases, so too does the cost of treatment. Together, these numbers have prompted an increase in the development of pharmaceutical interventions. HIV reverse transcriptase (HIV RT) has become a suitable target for drug therapy because it is the sole enzyme responsible for HIV replication.

Fucoidan, a sulfated polysaccharide isolated from the brown algae Fucus vesiculosus, has been shown to block a variety of cell adhesion related events including metastasis. In addition, fucoidan has also …


Playing With Fire: Science And Politics Of Air Pollution From Cars, Donald H. Stedman Mar 1995

Playing With Fire: Science And Politics Of Air Pollution From Cars, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.


Conversion Of Bovine Pancreatic Phospholipase A At A Single Site Into A Competitor Of Neurotoxic Phospholipases A By Site-Directed Mutagenesis, Mu-Chin Tzeng, Chon-Ho Yen, Ming-Jhy Hseu, Cynthia M. Dupureur, Ming-Daw Tsai Feb 1995

Conversion Of Bovine Pancreatic Phospholipase A At A Single Site Into A Competitor Of Neurotoxic Phospholipases A By Site-Directed Mutagenesis, Mu-Chin Tzeng, Chon-Ho Yen, Ming-Jhy Hseu, Cynthia M. Dupureur, Ming-Daw Tsai

Educator Preparation & Leadership Faculty Works

A 45-kDa polypeptide preferentially present in neuronal membranes was previously identified as a subunit of a binding (or receptor) protein for several phospholipase A2 variants with neurotoxicity, including crotoxin, by chemical cross-linking experiments (Yen, C.-H., and Tzeng, M.-C.(1991) Biochemistry 30, 11473-11477). The binding of crotoxin to this receptor protein was completely suppressed by sufficient F22Y, a mutated bovine pancreatic phospholipase A2 generated by site-directed mutagenesis of Phe of the wild-type enzyme to Tyr. The IC of this inhibition was estimated to be 1 μM. In sharp contrast, the wild-type enzyme gave no effect even at 50 μM. This …


Design And Performance Of The Advanced-Light-Source Double-Crystal Monochromator, G. Jones, S. Ryce, Dennis W. Lindle, B. A. Karlin, J. C. Woicik, Rupert C. Perera Feb 1995

Design And Performance Of The Advanced-Light-Source Double-Crystal Monochromator, G. Jones, S. Ryce, Dennis W. Lindle, B. A. Karlin, J. C. Woicik, Rupert C. Perera

Chemistry and Biochemistry Faculty Research

A new “Cowan type” double-crystal monochromator, based on the boomerang design used at National Synchrotron Light Source (NSLS) beamline X-24A, has been developed for beamline 9.3.1 at the Advanced Light Source (ALS), a windowless ultrahigh vacuum beamline covering the 1-6 keV photon-energy range. Beamline 9.3.1 is designed to simultaneously achieve the goals of high energy resolution, high flux, and high brightness at the sample. The mechanical design of the monochromator has been simplified, and recent developments in technology have been included. Measured mechanical precision of the monochromator shows significant improvement over existing designs. In tests with x-rays at NSLS beamline …


High-Brightness Beamline For X-Ray Spectroscopy At The Advanced Light Source, Rupert C. Perera, G. Jones, Dennis W. Lindle Feb 1995

High-Brightness Beamline For X-Ray Spectroscopy At The Advanced Light Source, Rupert C. Perera, G. Jones, Dennis W. Lindle

Chemistry and Biochemistry Faculty Research

Beamline 9.3.1 at the Advanced Light Source (ALS) is a windowless beamline, covering the 1-6 keV photon-energy range, designed to achieve the goals of high energy resolution, high flux, and high brightness at the sample. When completed later this year, it will be the first ALS monochromatic hard-x-ray beamline, and its brightness will be an order-of-magnitude higher than presently available in this energy range. In addition, it will provide flux and resolution comparable to any other beamline now in operation. To achieve these goals, two technical improvements, relative to existing x-ray beamlines, were incorporated. First, a somewhat novel optical design …


Removal Of Chlorinated Hydrocarbons From Water By Air Stripping And Solvent Sublation, Alpana Gami Jan 1995

Removal Of Chlorinated Hydrocarbons From Water By Air Stripping And Solvent Sublation, Alpana Gami

Theses

Removal of trichloroethylene, monochlorobenzene and 1,3 dichlorobenzene from water by air stripping and solvent sublation into an organic phase was investigated. The sublation solvents used were paraffin oil and decyl alcohol. The rate of removal from water by solvent sublation and air stripping was highest for trichloroethylene, followed by chlorobenzene and finally 1,3 dichlorobenzene. For the three compounds, solvent sublation had the greatest advantage over air stripping in the reduction of emission of the compounds to the atmosphere. For the three compounds, the removal was enhanced at higher flowrate in both air stripping and solvent sublation. For the removal of …


Highly Enantioselective Capillary Electrophoretic Separations With Dilute Solutions Of The Macrocyclic Antibiotic Ristocetin A, Daniel W. Armstrong, Mary P. Gasper, Kimber L. Rundlett Jan 1995

Highly Enantioselective Capillary Electrophoretic Separations With Dilute Solutions Of The Macrocyclic Antibiotic Ristocetin A, Daniel W. Armstrong, Mary P. Gasper, Kimber L. Rundlett

Chemistry Faculty Research & Creative Works

Ristocetin A is one of a series of structurally related amphoteric, glycopeptide, macrocyclic antibiotics. These compounds have several features that make them attractive as chiral selectors. These include spatially oriented functional groups that are known to provide the types of interactions that are conducive to enantio-recognition, a somewhat rigid "pocket" that can provide a site for hydrophobic interactions and polar, flexible arms (i.e., pendent sugar moieties) that can rotate to hydrogen bond and otherwise interact with a variety of chiral analytes. In addition, these compounds are sufficiently soluble in water, aqueous buffers and aqueous-organic solvents that are commonly used in …


Refinement Of The Solution Structure Of A Branched Dna Three-Way Junction, Neocles B. Leontis, Igor V. Ouporov Jan 1995

Refinement Of The Solution Structure Of A Branched Dna Three-Way Junction, Neocles B. Leontis, Igor V. Ouporov

Chemistry Faculty Publications

We have refined the structure of the DNA Three-Way Junction complex, TWJ- TC, described in the companion paper by quantitative analysis of two 2D NOESY spectra (mixing times 60 and 200 ms) obtained in D2O solution. NOESY crosspeak intensities extracted from these spectra were used in two kinds of refinement procedure: 1) distance-restrained energy minimization (EM) and molecular dynamics (MD) and 2) full relaxation matrix back calculation refinement. The global geometry of the refined model is very similar to that of a published, preliminary model (Leontis, 1993). Two of the helical arms of the junction are stacked. These are Helix …


A Spectroscopic Study Of A Rationally Designed Zinc Binding Protein, Jill Funk Jan 1995

A Spectroscopic Study Of A Rationally Designed Zinc Binding Protein, Jill Funk

Honors Theses, 1963-2015

Recently, biomedical science has turned its drug research endeavors towards a philosophy known as rational drug design. Its goal is to avoid the guesswork and instead design and create the exact proteins that are needed. In order for rational drug design to be feasible, a better understanding of protein structure and function needs to be obtained. This research analyses the structure and function of a "rationally" designed mutation of the calcium binding protein parvalbumin. Parvalbumin was chosen because certain aspects of its composition facilitate analysis and in addition, there is extensive data already known about the protein. The mutation involved …


Enantiomerically Enriched Α-Methyl Amino Acids. Use Of An Acyclic, Chiral Alanine-Derived Dianion With A High Diastereofacial Bias., David B. Berkowitz, Marianne K. Smith Jan 1995

Enantiomerically Enriched Α-Methyl Amino Acids. Use Of An Acyclic, Chiral Alanine-Derived Dianion With A High Diastereofacial Bias., David B. Berkowitz, Marianne K. Smith

David Berkowitz Publications

Hindered esters derived from N-benzoylalanine and the following chiral alcohols have been synthesized: (1) (−)-isopinocampheol; (2) (−)-trans-2-phenylcyclohexanol and (3) (−)-8-phenylmenthol. Sequential treatment of these esters with LDA (1.2 equiv.) and n-butyllithium (2.4 equiv.) at −78°C in THF generates the corresponding chiral dianions. Alkylation of each of these with benzyl bromide reveals that only the (−)-8-phenylmenthyl auxiliary confers a high diastereofacial bias upon its derivative dianion. In fact, that dianion (6) consistently displays diastereomeric ratios in the range of 89:11 to 94:6 for alkylations with a spectrum of nine alkyl halides. If one recrystallization step is …


Aggregation Of Chlorophyll A Probed By Resonance Light Scattering Spectroscopy, J. C. De Paula, J. H. Robblee, Robert F. Pasternack Jan 1995

Aggregation Of Chlorophyll A Probed By Resonance Light Scattering Spectroscopy, J. C. De Paula, J. H. Robblee, Robert F. Pasternack

Chemistry & Biochemistry Faculty Works

We report the resonance light scattering (RLS) spectra of chlorophyll a aggregated in a 9:1 solution of formamide and pH 6.8 phosphate buffer. The aggregate formed after 2 h of mixing, referred to as Chl(469), shows a strong scattering feature at 469 nm (Soret band) and a much weaker feature at 699 nm (Q(y) band). A kinetic investigation confirmed that the aggregation process is cooperative, and also detected one intermediate (Chl(458)) with a strong RLS spectrum but only a weak CD spectrum. We propose that aggregation proceeds via at least three steps: 1) formation of a nucleating species, probably a …


The Molecular Process By Which Streptococcus Pneumoniae Activates The Immune System During Pneumococcal Infection, Brandon Abeyta Jan 1995

The Molecular Process By Which Streptococcus Pneumoniae Activates The Immune System During Pneumococcal Infection, Brandon Abeyta

Whittier Scholars Program

This project includes a review of literature detailing the human body's defense mechanisms against Streptococcus pneumoniae. Research includes the use of a rabbit-model of the human immune system searching for a vaccine by experimenting with different portions of pneumococcal cell wall. Comprehend infection with the conclusions the cell walls are a powerful inducer of inflammatory response. Studied at Rockefeller University and learned under Dr. Elaine Tuomanen at Laboratory of Molecular Infectious Diseases.


Syntheses Of Cross-Linking Agents, Molecular Modeling Of Oligonucleotides And Polypeptide-Ion Complexes, Michael J. Yunes Jan 1995

Syntheses Of Cross-Linking Agents, Molecular Modeling Of Oligonucleotides And Polypeptide-Ion Complexes, Michael J. Yunes

Honors Theses

Each section of this thesis will be subdivided into three parts encompassing all of the research in which I have been involved during the past three years. These will be referred to under the headings "Syntheses:' "Molecular Modeling," and "Cross-linking Efficiencies." Each of these subdivisions may have divisions within them when necessary in order to fully detail the research.


Electrochemical Studies Of Hemoglobin And Cross-Linked Hemoglobin, Ayoola O. Alabi Jan 1995

Electrochemical Studies Of Hemoglobin And Cross-Linked Hemoglobin, Ayoola O. Alabi

Master's Theses

No abstract provided.


Ignition And Environmental Effects Of Wildfires As Related To Giant Impacts, Gregory S. Kufner Jan 1995

Ignition And Environmental Effects Of Wildfires As Related To Giant Impacts, Gregory S. Kufner

Honors Projects

Soot has been discovered by Wolbach et al. at the Cretaceous-Tertiary boundary in various geographic locations, supporting the theory that worldwide wildfires were ignited by the impact of a giant meteorite which caused the mass extinction 65 million years ago. This project examines a deep sea core sample from the North Central Pacific Ocean for evidence of soot. Soot discovery at this site, the only deep ocean site to be studied, supports the theory that soot distribution from the fires was worldwide. In another project, samples from the suevite breccia of the Kara Ust-Kara craters in Russia (unrelated to the …


Organochlorine Pesticide Residues In The Neotropical Migratory Passerine Birds, Birthe Borup Jan 1995

Organochlorine Pesticide Residues In The Neotropical Migratory Passerine Birds, Birthe Borup

Honors Projects

In 1874 Othmar Ziedlert a German chemist was working on the synthesis and characterization of substituted aromatic hydrocarbons. In the process of his work he synthesized dichloro-diphenyl-trichloro-ethane commonly known as DDT. It was not until 1930 that its use as an insecticide was detected by Paul Muller who found that it was effective against potato beetles (Leptinotarsal declineata) and clothes moths, (Tineola besselliella ) (Dunlap 1981). Pure DDT is a white crystalline solid with a melting point of 109 C, and a vapor pressure of 0.025mPa at 20 C. Technical grade DDT is a white amorphous powder, consisting of a …


Helical Stacking In Dna 3-Way Junctions Containing 2 Unpaired Pyrimidines - Proton Nmr-Studies, Neocles B. Leontis, Michael T. Hills, Martial Piotto, Igor V. Ouporov, Arun Malhotra, David G. Gorenstein Jan 1995

Helical Stacking In Dna 3-Way Junctions Containing 2 Unpaired Pyrimidines - Proton Nmr-Studies, Neocles B. Leontis, Michael T. Hills, Martial Piotto, Igor V. Ouporov, Arun Malhotra, David G. Gorenstein

Chemistry Faculty Publications

The proton NMR spectra of DNA three-way junction complexes (TWJ) having unpaired pyrimidines, 5'-TT- and 5'-TC- on one strand at the junction site were assigned from 2D NOESY spectra acquired in H2O and D2O solvents and homonuclear 3D NOESY-TOCSY and 3D NOESY-NOESY in D2O solvent. TWJ are the simplest branched structures found in biologically active nucleic acids. Unpaired nucleotides are common features of such structures and have been shown to stabilize junction formation. The NMR data confirm that the component oligonucleotides assemble to form conformationally homogeneous TWJ complexes having three double-helical, B-form arms. Two of the helical arms stack upon …


Electrochemical, Chromatographic, And Spectrometric Studies Of An Osmium Containing Polymer, Lawrence John Rhodes Jan 1995

Electrochemical, Chromatographic, And Spectrometric Studies Of An Osmium Containing Polymer, Lawrence John Rhodes

Master's Theses

No abstract provided.


The Synthesis Of N-Chlorosulfonyl Β-Lactams And Their Rearrangements, Lihua Zhang Jan 1995

The Synthesis Of N-Chlorosulfonyl Β-Lactams And Their Rearrangements, Lihua Zhang

Masters Theses

The synthesis of several N-chlorosulfonyl-β-lactams and their rearrangements have been carried out via CSI (chlorosulfonylisocyanate) reaction. The mechanism of β-lactam synthesis as well as its rearrangements were also studied. The characterization of β-lactams was performed with IR, 1H and 13C NMR, and HRMS. β-lactams 2-chlorosulfonyl-1-methyl-2-azabicyclo[4.2.0]octan-3-one (71), 1-chlorosulfonyl-4-methyl-4- (phenylmethyl)azetidin-2-one (74) and 1-chlorosulfonyl-4,4- (diphenylmethyl)azetidin-2-one (75) were synthesized for the first time. β-lactam 4-chlorosulfonyl-3, 9, 9-trimethyl-4-azatricyclo [6.1.0.03,6] nonan-5-one (73) was obtained as crystalline solid instead of liquid.

Different effects, such as temperature, solvents and catalysts, on the rearrangement of the …


The Synthesis And Characterization Of [Ruii (Bpy) 2 (Biphen) ] (Pf6)2 And [ (Bpy) 2ruii (Biphen) Ruii (Bpy) 2] (Pf6)4, Mei-Yueh Chang Jan 1995

The Synthesis And Characterization Of [Ruii (Bpy) 2 (Biphen) ] (Pf6)2 And [ (Bpy) 2ruii (Biphen) Ruii (Bpy) 2] (Pf6)4, Mei-Yueh Chang

Masters Theses

A new bidentate polypyridine bridging ligand (biphen), produced by the condensation of 1,10-phenanthroline-5,6-dione with 5,6-diamino-phenanthroline has been synthesized and characterized. In addition the monometallic complex [(bpy)2RuII(biphen)](PF6)2 and the bimetallic complex [(bpy)2RuII(biphen)RuII(bpy)2](PF6)4 have been prepared. The complexes were characterized by elemental analysis, by 1H-NMR spectroscopy and by cyclic voltsmmetry(CV).

The results of these analyses seem to indicate that biphen acts like two independent units when attached to a - RuII(bpy)2 fragment. a bipyridine portion and a phenazine portion. Moreover, …


New Optical Cell Design For Laser Flash Photolysis Studies In Supercritical Fluids, Steven R. Goates, Milton L. Lee, Qin Ji, Edward M. Eyring, Rudi Van Eldik, Kedika Bal Reddy Jan 1995

New Optical Cell Design For Laser Flash Photolysis Studies In Supercritical Fluids, Steven R. Goates, Milton L. Lee, Qin Ji, Edward M. Eyring, Rudi Van Eldik, Kedika Bal Reddy

Faculty Publications

A high-pressure optical cell has been designed that achieves an effective separation between the chemical sample and the pressurizing medium and system. This design limits possible sample contamination and catalytic effects under supercritical fluid sample conditions. Laser flash photolysis experiments were carried out on molybdenum hexacarbonyl dissolved in supercritical CO2. The thermal ring closure reaction of the species Mo(CO)5L, where L is 2,2- bipyridine was found to proceed at rates comparable to those measured previously in liquid benzene or toluene. Much larger activation volumes were found for the reaction in supercritical CO2 than in liquid toluene.