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Adhesion Of Glow Discharge Polymers To Metals And Polymers, N. Inagaki, H. Yasuda Jan 1981

Adhesion Of Glow Discharge Polymers To Metals And Polymers, N. Inagaki, H. Yasuda

Chemistry Faculty Research & Creative Works

Adhesion of glow discharge polymers to metals and polymers in an adhesive joint was measured by lap‐shear test and immersion in hot water of 70°C for an extended time. A glow discharge polymer was deposited onto polymers [polyethylene and poly(tetrafluoroethylene)] and metals (aluminum and stainless steel) prior to when the polymer and metal were joined. It is found that the lap‐shear strength is enhanced by coating the surfaces of these substrates with plasma film produced from methane, ethylene, and acetylene, and that deterioration of the adhesive bonding part, when immersed in hot water of 70°C, is strongly dependent on the …


The Effect Of Plasma-Deposited Polymers On The Nucleate Boiling Behavior Of Copper Heat Transfer Surfaces, T. Hinrichs, E. Hennecke, H. Yasuda Jan 1981

The Effect Of Plasma-Deposited Polymers On The Nucleate Boiling Behavior Of Copper Heat Transfer Surfaces, T. Hinrichs, E. Hennecke, H. Yasuda

Chemistry Faculty Research & Creative Works

The effect of plasma deposited polymers on the nucleate boiling behavior of copper heat transfer surfaces, using water as the boiling liquid, was determined. The monomers used were tetrafluoroethylene (TFE) and methane. It was found that an 18 nm thick coating of TFE enhanced the nucleate boiling, while a 150 nm thick coating reduced the nucleate boiling. Both 15 nm and 150 nm thick coatings of methane reduced the nucleate boiling, with the effect being more pronounced with the thicker coating. A surface energy effect is postulated to explain the enhanced boiling observed. © 1981.


The Initial And Terminating Stage Of Glow Discharge Polymerization Investigated By Thickness Monitor, N. Inagaki, H. Yasuda Jan 1981

The Initial And Terminating Stage Of Glow Discharge Polymerization Investigated By Thickness Monitor, N. Inagaki, H. Yasuda

Chemistry Faculty Research & Creative Works

An attempt to discuss the initial stage and terminating stage of glow discharge polymerization was made by selecting the monomer system of styrene and acetylene, which differ in their condensability, and a certain polymerization procedure. Results indicate the important aspects of the initial and terminating stages of glow discharge polymerization. These aspects may not play a significant role in the study of bulk properties of plasma‐polymerized polymers or in the study of polymer deposition rate. However, the initial stage effect might influence the adhesion of the polymer. The terminating stage effect might influence the surface characteristics of glow discharge‐polymerized polymers. …


Thermal Decomposition Kinetics Of Asf5-Doped Polyacetylene In Vacuum, T. Inoue, J. E. Osterholm, H. Yasuda, L. L. Levenson Dec 1980

Thermal Decomposition Kinetics Of Asf5-Doped Polyacetylene In Vacuum, T. Inoue, J. E. Osterholm, H. Yasuda, L. L. Levenson

Physics Faculty Research & Creative Works

Electrical conductivity measurements, mass spectra of desorbing species, and ESCA surface analysis are reported for AsF5-doped polyacetylene heated between 50 and 130°C in vacuum. All measurements indicate first-order decomposition kinetics with activation energies between 13 and 20 kcal mole-1. Decomposition leads to the desorption of AsF3 and F2. Metallic arsenic remains in the polyacetylene as a decomposition by-product.


Iron And Life, Thomas Emery Nov 1980

Iron And Life, Thomas Emery

Faculty Honor Lectures

Iron, iron, everywhere but. . . . The plight of the ancient mariner surrounded by undrinkable water could hardly have been more frustrating than life on earth with respect to iron. Iron is the fourth most abundant element of the earth's surface, exceeded only by oxygen, silicon, and aluminum. Virtually all forms of life from the simplest bacteria to humans require iron to catalyze numerous and complex metabolic reactions. Because of the diversity and complexity of the role of iron in the life process, it has even been suggested that the origin of life on earth centered around the catalytic …


22nd Rocky Mountain Conference On Analytical Chemistry Aug 1980

22nd Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Abstracts and meeting program from the 22nd annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy and the Rocky Mountain Chromatography Discussion Group. Held in Denver, Colorado, August 10-14, 1980.


Evolution Of A Cooling Water Treatment Program At A Chemical Processing Plant, Lawrence P. Everson Jul 1980

Evolution Of A Cooling Water Treatment Program At A Chemical Processing Plant, Lawrence P. Everson

Retrospective Theses and Dissertations

During the construction of a chemical processing plant, a polyphosphate product was selected for use as a corrosion inhibitor in the open recirculating cooling tower system. After several months of operation, problems in the system made evident the fact that polyphosphate as a corrosion inhibitor was not acceptable. An organic corrosion inhibitor was substituted for the phosphate, resulting in improved corrosion protection and the elimination of phosphate fouling.


Pressure Dependence Of Fluorescent And Photolytic Interferences In Ho Detection By Laser-Excited Fluorescence, Thomas M. Hard, Robert J. O'Brien, T. B. Cook Jul 1980

Pressure Dependence Of Fluorescent And Photolytic Interferences In Ho Detection By Laser-Excited Fluorescence, Thomas M. Hard, Robert J. O'Brien, T. B. Cook

Chemistry Faculty Publications and Presentations

In the measurement of HO concentrations by laser-excited fluorescence, expansion of the sampled air offers a way to reduce fluorescent and photolytic interference by other species. The decrease in [HO] upon expansion is balanced by an increase in HO fluorescence yield over a wide range of pressures. Background air fluorescence is reduced if the responsible species have fluorescence yields higher than those of HO. Preliminary experiments indicate that most of the fluorescence observed in laboratory air is due to such species. Upon expansion, the suppression of fluorescent interference can be no greater than the reduction in pressure, whereas the suppression …


Transient Phenomena Of Polymer : Aniline-Formaldehyde Fiber And Copolymer Aniline-Phenol-Formaldehyde Fiber, Ing-On Vibulbhan-Watts May 1980

Transient Phenomena Of Polymer : Aniline-Formaldehyde Fiber And Copolymer Aniline-Phenol-Formaldehyde Fiber, Ing-On Vibulbhan-Watts

Theses

The rotational viscometer which had a uniform stress, designed by Dr. W. Philippoff was used for measuring the viscosities of 6% L-200 in PRIMOL 355 and Lekutherm x-30. Viscosities of 6% L-200 in PRIMOL 355 (polyisobutylene) was measured to check the change of material that was left in the visometer for almost two years. The result showed that the new viscosities are higher than the older results.


The Use Of Thermal Analysis In The Identification And Characterization Of Fibers Of Forensic Interest, Ronald J. Coffey May 1980

The Use Of Thermal Analysis In The Identification And Characterization Of Fibers Of Forensic Interest, Ronald J. Coffey

All-Inclusive List of Electronic Theses and Dissertations

This study investigates the use of thermal analysis for the identification and characterization of fibers for forensic purposes. Fibers such as polyesters, polyacrylics, polypropylenes and nylon were investigated by Differential Thermal Analysis (D.T.A.) and Thermogravimetric Analysis (T.G.A.) to see if their resulting thermograms were characteristic of each fiber. Also, infrared analysis was performed on each fiber. In addition, such factors as heating rate and sample size along with fiber blends were studied as to their effect on thermograms. As a result of this study several important conclusions may be drawn. Although it was found that for the most part D.T.A. …


The Limnological Status Of Lake Mead And Lake Mohave Under Present And Future Powerplant Operations Of Hoover Dam, Larry J. Paulson, John R. Baker, James E. Deacon, U.S. Water And Power Resources Service Jan 1980

The Limnological Status Of Lake Mead And Lake Mohave Under Present And Future Powerplant Operations Of Hoover Dam, Larry J. Paulson, John R. Baker, James E. Deacon, U.S. Water And Power Resources Service

Publications (WR)

The ever-increasing demand for energy in the southwest has led to a search for additional sources of power generation. Coal-fired powerplants currently provide most of the baseline energy in the southwest, but this must be supplemented with hydroelectric power during periods of peak demand. In order to provide additional peaking power, the U.S. Bureau of Reclamation is considering a number of projects to modify existing hydroelectric facilities, or add new facilities in the Lake Mead Recreation Area. The Hoover Powerplant Modification Feasibility Investigation was authorized by Congress on December 16, 1975 to determine the feasibility of: (i) adding one or …


Ruthenium-Catalyzed Hydrogenation Of Aqueous Sodium Bicarbonate, Duane P. Covino Jan 1980

Ruthenium-Catalyzed Hydrogenation Of Aqueous Sodium Bicarbonate, Duane P. Covino

Retrospective Theses and Dissertations

This research report investigated the ruthenium-catalyzed hydrogenation of aqueous sodium bicarbonate. Subjects of the investigation included: the "blank" effect of the 316 stainless steel reactor in the batch mode; the catalytic activities at 150°C for unsupported ruthenium, including ruthenium purge and the metal produced from the in situ reduction of RuCl3·1-3H2O and Ru(IV)O2·H2O; the catalytic activities at 150°C for supported ruthenium including 4.05% w/w ruthenium on alumina, 5.25 and 20.85%w/w ruthenium on molecular sieve SK-41 (ammonium - substituted Y-type), 3.34 and 17.48% w/w ruthenium on SK-41 (prepared by the in situ reduction of the RuCl3·1-3H2O exchange sieve); orders of reaction …


Luminescence In Slipped And Dislocation-Free Laser-Annealed Silicon, R.H. Uebbing, P. Wagner, H. Baumgart, H. J. Queisser Jan 1980

Luminescence In Slipped And Dislocation-Free Laser-Annealed Silicon, R.H. Uebbing, P. Wagner, H. Baumgart, H. J. Queisser

Electrical & Computer Engineering Faculty Publications

Photoluminescence of cw laser-annealed silicon shows a dramatic difference in electronic behavior of the reconstructed material depending upon either creation or suppression of dislocations. Beyond a critical exposure time slip appears, and the luminescence of these samples is dominated by dislocation-related defect levels.


Analysis Of Mixtures Of Chlorine, Chlorine Dioxide And Chlorite, Ying-Chien Chu Dec 1979

Analysis Of Mixtures Of Chlorine, Chlorine Dioxide And Chlorite, Ying-Chien Chu

Masters Theses

No abstract provided.


Flat-Band Potential Of N-Type Semiconducting Molybdenum Disulfide By Cyclic Voltammetry Of Two-Electron Reductants: Interface Energetics And The Sustained Photooxidation Of Chloride, Lynn Schneemeyer, Mark S. Wrighton Sep 1979

Flat-Band Potential Of N-Type Semiconducting Molybdenum Disulfide By Cyclic Voltammetry Of Two-Electron Reductants: Interface Energetics And The Sustained Photooxidation Of Chloride, Lynn Schneemeyer, Mark S. Wrighton

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

Cyclic voltammetry has been used to locate the band edges of n-type MoS2 in CH3CN/ and EtOH/[n-Bu4N]ClO4 solutions. The crucial experiments concern the study of the cyclic voltammetry of biferrocene (BF) and N,N,N',N'-tetra-methyl-p-phenylenediamine (TMPD) each of which has two, reversible, one-electron waves at Pt. At MoS2, the first oxidation is reversible in the dark, whereas the second oxidation is observed only upon illumination of the MoS2. The dark oxidation BF → BF+ and the photoanodic BF+ → BF2+ are separated by only ~150 mV, allowing us to assign an uncommonly accurate flat-band potential of +0.30 + 0.05 V vs. SCE …


21st Rocky Mountain Conference On Analytical Chemistry Jul 1979

21st Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Abstracts and meeting program from the 21st annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy and the Rocky Mountain Chromatography Discussion Group. Held in Denver, Colorado, July 30 - August 1, 1979.


Preparation Of A Polymer Supported Cobalt (Ii) Schiff Base Catalyst, Susan L. Fuhrman Apr 1979

Preparation Of A Polymer Supported Cobalt (Ii) Schiff Base Catalyst, Susan L. Fuhrman

Retrospective Theses and Dissertations

Polystyrene bis(salicylaldehyde)-propylene-1,3-diiminato Cobalt (II) (salen) and Polystyrene bis(acetylacetone)-propylene-1,3-diiminato Cobalt (II) (BAE) were prepared stepwise from polystyrl chloride. The reaction series included substitution of the chloride with a malononitrile carbanion, reduction to a diamine, condensation to form a Schiff base, and complexation with Co(II) acetate to form the active polymeric material. Optimum conditions with regard to time, temperature, reaction ratios, and solvent were determined for each reaction. The ability of the polymer bound cobalt complex to oxidize 3-methyl indole was measure. The BAE catalyst yielded a large amount of the corresponding o-formylaminoacetophenone. However, the exact yield is not known because product …


Raman Scattering Study Of Cs2 In Cci4, Scott Whittenburg Mar 1979

Raman Scattering Study Of Cs2 In Cci4, Scott Whittenburg

Chemistry Faculty Publications

No abstract provided.


Lake Mead And Lake Powell Salinity Reports, Cathy Lee, Steve Gazafy Feb 1979

Lake Mead And Lake Powell Salinity Reports, Cathy Lee, Steve Gazafy

Publications (WR)

The enclosed reports were compiled for the Colorado River Water Quality Office based on salinity data for Lake Mead and Lake Powell. According to the regional director of the office, the reports are not considered "polished" documents for public distribution. However, he considers them to be "interesting, rough appraisals of general trends that may be very important In our understanding the hydro-salinity system in the Colorado River."


Stripping Platinum Metals From Catalytic Converter Units By Use Of Promoted Gas Phase Chlorine Attack, James Harold Finckbone Jan 1979

Stripping Platinum Metals From Catalytic Converter Units By Use Of Promoted Gas Phase Chlorine Attack, James Harold Finckbone

Retrospective Theses and Dissertations

A gas-phase system to oxidize and remove the platinum and palladium from automotive catalytic converter units was studied. The effects of varying reaction temperature, time and reactant gas concentration upon yields were monitored using a colorimetric procedure based on the regent p-nitroso-N, N-dimethyl amiline. Chlorine plus carbon monoxide at 700°-900°C. displayed the most promise for commercial application.


A Polarographic Study Of Fe(Ii) And Fe(Iii) Complexes With Catechol, Wen-Tang Shen Jan 1979

A Polarographic Study Of Fe(Ii) And Fe(Iii) Complexes With Catechol, Wen-Tang Shen

Dissertations and Theses

A study of the anodic polarography of catechol in 0.100 F sodium perchlorate is presented. A new wave is observed in alkaline solutions which is different from the simple oxidation wave of catechol to ortho-quinone observed by previous workers. The importance of buffer materials is discussed and a possible explanation of the new wave is suggested.

A study of the polarography behavior of Fe(II) and Fe(III) in the presence of catechol is reported. In the case of reduction of Fe(III) in the presence of catechol, two steps occur at about -1.5 and -1.8 volts (vs. SCE) at pH higher than …


Separation Of 1,3-Pentadiene With Molecular Sieves, Steven R. Schwinn Jan 1979

Separation Of 1,3-Pentadiene With Molecular Sieves, Steven R. Schwinn

Retrospective Theses and Dissertations

The feasibility of separating piperylene (1,3-pentadiene) from a mixture of five-carbon olefins and diolefins with Linde 5A Molecular Sieves was investigated. Olefins and especially diolefins are very reactive and tend to polymerize on the highly polar adsorptive surface thereby clogging the pores of themolecular sieve. It is believed that the acid sites within the zeolite cages catalyze this polymerization reaction and that poisoning of these sites by adsorption of a nitrogenous base (ethylenediamine, dimethylamine or ammonia) or hydrogen sulfide inhibits the formation of polymers. Two criteria were used in the evaluation of the polymerization inhibitors tested. First, a series of …


Fate Of Some Common Radionuclides Found In Dardanelle Lake, David M. Chittenden Ii Jan 1979

Fate Of Some Common Radionuclides Found In Dardanelle Lake, David M. Chittenden Ii

Journal of the Arkansas Academy of Science

Four factors influence the concentrations of radionuclides in Dardanelle Lake water: injections due to fallout and discharge from Nuclear I coupled with losses due to decay, to dilution and to sedimentation. It is possible to estimate the first three factors and to measure monthly changes in the concentrations of Sr-89, Ce-141, Cs-137, Co-38, Ce-144, and Sr-90 - Y-90 during periods when the concentrations of these nuclides are abnormally high (after large releases or the Chinese weapons tests) or abnormally low (during reactor refueling).


Plasma Polymerization Of Tetrafluoroethylene. Iii. Capacitive Audio Frequency (10 Khz) And Ac Discharge, N. (Nicholas) C. Morosoff, H. Yasuda, E. S. Brandt, C. N. Reilley Jan 1979

Plasma Polymerization Of Tetrafluoroethylene. Iii. Capacitive Audio Frequency (10 Khz) And Ac Discharge, N. (Nicholas) C. Morosoff, H. Yasuda, E. S. Brandt, C. N. Reilley

Chemical and Biochemical Engineering Faculty Research & Creative Works

The plasma polymerization of tetrafluoroethylene (TFE) is studied in a capacitively coupled system with internal electrodes using a 10 kHz (af) and a 60 Hz (ac) source. The emphasis is on identifying conditions that are compatible with continuous coating of plasma polymer on a substrate moving through the center of the interelectrode gap. Operation at a pressure below 100 mTorr is most favorable for deposition of a substantial portion of the plasma polymer on this substrate. Plasma polymer deposited in this way is characterized by ESCA and by deposition rate data and compared to that deposited using rf power in …


Plasma Polymerization Of Tetrafluoroethylene. Ii. Capacitive Radio Frequency Discharge, N. (Nicholas) C. Morosoff, H. Yasuda, E. S. Brandt, C. N. Reilley Jan 1979

Plasma Polymerization Of Tetrafluoroethylene. Ii. Capacitive Radio Frequency Discharge, N. (Nicholas) C. Morosoff, H. Yasuda, E. S. Brandt, C. N. Reilley

Chemical and Biochemical Engineering Faculty Research & Creative Works

The plasma polymerization of tetrafluoroethylene (TFE) is studied in a capacitively coupled system with internal electrodes using radio frequency (13.56 MHz) power. The emphasis is on identifying conditions that are compatible with continuous coating of plasma polymer on a substrate moving through the center of the interelectrode gap. At high pressure (500 mTorr), deposition of plasma polymer is primarily on the electrodes rather than on a substrate placed midway between electrodes. Glow is observed in only part of the interelectrode gap at low powers and fills the gap only at high power levels. The use of a magnetic field effects …


A Simple Experiment Illustrating The Structure Of Association Colloids, Stig Friberg, Beverly Bendiksen Jan 1979

A Simple Experiment Illustrating The Structure Of Association Colloids, Stig Friberg, Beverly Bendiksen

Chemistry Faculty Research & Creative Works

No abstract provided.


Nucleation Experiments With Monodisperse Nacl Aerosols., Darryl J. Alofs, M. B. Trueblood, D. R. White, V. L. Behr Jan 1979

Nucleation Experiments With Monodisperse Nacl Aerosols., Darryl J. Alofs, M. B. Trueblood, D. R. White, V. L. Behr

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Nucleation Experiments with Monodisperse NaCl Aerosols Showed Good Agreement with the Kohler Theory Relating the Critical Super-Saturation S//c to the Dry Size. Aerosols Produced by Condensing NaCl Showed the Same S//c as Those Produced by Evaporating Aqueous NaCl Solution Droplets. This Indicates that If There is an Energy Barrier in Going from a Dry NaCl Particle to a Solution Droplet, This Energy Barrier is Small. the Fact that the Evaporation Aerosol Particles Are Cubical Crystals and the Condensation Aerosols Are Amorphous Spheres is Shown to Make No Difference in the Nucleation Threshold. the Investigation Also Gives Insights into the Performance …


Plasma Polymerization Of Tetrafluoroethylene. I. Inductive Radio Frequency Discharge, H. Yasuda, N. Morosoff, E. S. Brandt, C. N. Reilley Jan 1979

Plasma Polymerization Of Tetrafluoroethylene. I. Inductive Radio Frequency Discharge, H. Yasuda, N. Morosoff, E. S. Brandt, C. N. Reilley

Chemistry Faculty Research & Creative Works

The plasma polymerization of tetrafluoroethylene in an inductively coupled radio frequency glow discharge, using a flow system, was studied. A simple long tube reactor, with the coupling coil placed at the middle of the tube and gas entrance and exit at the respective ends, was used. Deposition rates and the chemical nature of the polymer (as revealed by ESCA spectra and surface energy studies) are obtained as a function of location in the reactor tube with respect to the coupling coil and of applied energy per unit mass of tetrafluoroethylene (W/FM). It was found that a fluorine poor polymer, containing …


20th Annual Rocky Mountain Conference On Analytical Chemistry Aug 1978

20th Annual Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Abstracts and program from the 20th annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy and the Rocky Mountain Chromatography Discussion Group. Held in Denver, Colorado, August 7-9, 1978.


Thermodynamics Of The Lanthanide Trifluorides. I. The Heat Capacity Of Lanthanum Trifluoride, Laf₃ From 5 To 350°K And Enthalpies From 298 To 1477°K, William G. Lyon, Darrell W. Osborne, Howard E. Flotow, Fernande Grandjean, Ward N. Hubbard, Gerald K. Johnson Jul 1978

Thermodynamics Of The Lanthanide Trifluorides. I. The Heat Capacity Of Lanthanum Trifluoride, Laf₃ From 5 To 350°K And Enthalpies From 298 To 1477°K, William G. Lyon, Darrell W. Osborne, Howard E. Flotow, Fernande Grandjean, Ward N. Hubbard, Gerald K. Johnson

Chemistry Faculty Research & Creative Works

The heat capacity of a sample of LaF3 was determined in the temperature range 5-350°K by aneroid adiabatic calorimetry and the enthalpy from 298.15 to 1477°K by drop calorimetry. The heat capacity at constant pressure C°p(298.15°K), the entropy S°(298.15°K), the enthalpy [H°(298.15°K)-H°(0)] and the Planck function -[G°(298.15°K)-H°(0)]/298.15°K; were found to be (90.29±0.09) J °K-1·mole-1, (106.98±0.11) J °K-1·mole-1, (16717±17) J mole-1, and (50.91±0.05) J °K -1·mole-1. The thermal functions from the present research were extended up to the melting temperature (1766°K) by combination with previously …