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Articles 1 - 26 of 26
Full-Text Articles in Physical Sciences and Mathematics
New Multidetector Solution Could Lead To Safer Alternatives To Faulty Silicone Breast Implants, Judit D. Puskas, Geof Wyatt
New Multidetector Solution Could Lead To Safer Alternatives To Faulty Silicone Breast Implants, Judit D. Puskas, Geof Wyatt
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
The article discusses the effort of the University of Akron's Department of Chemical and Biomolecular Engineering to pursue research which aims to reduce or eliminate capsular contracture associated with breast implants. It notes that the new multidetector nanotechnology developed by researchers can be better alternative to silicone gel-filled breast implants. It mentions that the new technology can also help in early diagnosis and imaging of breast cancer.
Effect Of Nanoscale Confinement On Glass Transition Of Polystyrene Domains From Self-Assembly Of Block Copolymers, C. G. Robertson, T. E. Hogan, M. Rackaitis, Judit D. Puskas, X. Wang
Effect Of Nanoscale Confinement On Glass Transition Of Polystyrene Domains From Self-Assembly Of Block Copolymers, C. G. Robertson, T. E. Hogan, M. Rackaitis, Judit D. Puskas, X. Wang
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
The understanding of size-dependent properties is key to the implementation of nanotechnology. One controversial and unresolved topic is the influence of characteristic size on the glass transition temperature (T(g)) for ultrathin films and other nanoscale geometries. We show that T(g) does depend on size for polystyrene spherical domains with diameters from 20 to 70 nm which are formed from phase separation of diblock copolymers containing a poly(styrene-co-butadiene) soft block and a polystyrene hard block. A comparison of our data with published results on other block copolymer systems indicates that the size dependence of T(g) is a consequence of diffuse interfaces …
Investigation Of The Physical And Electronic Properties Of Indium Doped Zinc Oxide Nanofibers Synthesized By Electrospinning, A. F. Lotus, Y. C. Kang, R. D. Ramsier, George G. Chase
Investigation Of The Physical And Electronic Properties Of Indium Doped Zinc Oxide Nanofibers Synthesized By Electrospinning, A. F. Lotus, Y. C. Kang, R. D. Ramsier, George G. Chase
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
Nanostructured metal oxides and particularly nanofiber based materials can provide significant advances for the miniaturization of electronic, optoelectronic, photonic, sensor, and energy conversion devices with enhanced performance based on their unique material properties. In this study, indium doped zinc oxide (IZO) nanofibers were synthesized by electrospinning. These nanofibers have diameters in the range 50-100 nm. The effects of indium addition on the structural, optical, and electrical properties of the zinc oxide nanofiber matrices were investigated. The IZO nanofibers undergo significant changes in their optical and electrical properties compared to undoped zinc oxide nanofibers.
Electrospinning Route For The Fabrication Of P-N Junction Using Nanofiber Yarns, A. F. Lotus, S. Bhargava, E. T. Bender, E. A. Evans, R. D. Ramsier, D. H. Reneker, George G. Chase
Electrospinning Route For The Fabrication Of P-N Junction Using Nanofiber Yarns, A. F. Lotus, S. Bhargava, E. T. Bender, E. A. Evans, R. D. Ramsier, D. H. Reneker, George G. Chase
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
Electrospinning is a simple, versatile, and cost effective method for generating nanoscale fibers, wires, and tubes. Nanowires and nanotubes could be important building blocks for nanoscale electronics, optoelectronics, and sensors as they can function as miniaturized devices as well as electrical interconnects. We report on a simple method to fabricate free standing ceramic nanofiber heterostructures, which exhibit rectifying behavior of a p-n junction.
Modeling And Simulation Of Coating Growth On Nanofibers, J. Wilder, C. B. Clemons, K. L. Kreider, G. W. Young, Edward A. Evans, G. Zhang
Modeling And Simulation Of Coating Growth On Nanofibers, J. Wilder, C. B. Clemons, K. L. Kreider, G. W. Young, Edward A. Evans, G. Zhang
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
This work presents modeling and simulation results of a procedure to coat nanofibers and core-clad nanostructures with thin film materials using plasma enhanced physical vapor deposition. In the experimental effort that motivates the modeling, electrospun polymer nanofibers are coated with metallic materials under different operating conditions to observe changes in the coating morphology. The modeling effort focuses on linking simple models at the reactor, nanofiber, and atomic levels to form a comprehensive model. Numerical simulations that link the concentration field with the evolution of the coating free surface predict that as the Damkohler number is increased the coating morphology changes …
Palladium Nanoparticles Supported By Alumina Nanofibers Synthesized By Electrospinning, S. J. Park, S. Bhargava, E. T. Bender, George G. Chase, R. D. Ramsier
Palladium Nanoparticles Supported By Alumina Nanofibers Synthesized By Electrospinning, S. J. Park, S. Bhargava, E. T. Bender, George G. Chase, R. D. Ramsier
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
Palladium nanoparticles supported by alumina nanofibers have been successfully synthesized by electrospinning using palladium chloride incorporated into a solution of polyvinyl pyrrolidone and aluminum acetate. Palladium agglomerate sizes and the surface morphology of the electrospun nanofibers were determined by transmission electron microscopy. Palladium nanoparticles appeared to be well dispersed within the electrospun nanofiber structure. X-ray diffraction, x-ray photoelectron spectroscopy, and Raman scattering spectroscopy techniques were used to identify the crystalline form and distinguish between oxidized and metallic palladium particles after heating and hydrogenation.
Fluorescence Characteristics Of Triazine-Manufacturing Wastewater, Lin Huang, Shuyan Qiu, Neissa Pinzon, Li-Ta Lien, Lu-Kwang Ju
Fluorescence Characteristics Of Triazine-Manufacturing Wastewater, Lin Huang, Shuyan Qiu, Neissa Pinzon, Li-Ta Lien, Lu-Kwang Ju
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
Samples taken at different points in the wastewater treatment process of a triazine-manufacturing plant were scanned by fluorescence spectroscopy, in the wavelength range of 200-900 nm. Reproducibly, the fluorescence spectra revealed one single major peak at excitation and emission wavelengths of 258 and 370 nm respectively. Aqueous solutions of purified active compounds, including Atrazine, Propazine, Simazine, Terbuthylazine, Metolachlor, and Benoxacor, were also scanned. No significant fluorescence was observed in these standard solutions at concentrations up to 100 mg/L. Selected plant samples as well as standard solutions of Atrazine, Metolachlor, and toluene were further analyzed using high-performance liquid chromatography with absorbance …
Characterization Of Zirconium Nitride Films Sputter Deposited With An Extensive Range Of Nitrogen Flow Rates, N. Farkas, G. Zhang, R. D. Ramsier, Edward A. Evans, J. A. Dagata
Characterization Of Zirconium Nitride Films Sputter Deposited With An Extensive Range Of Nitrogen Flow Rates, N. Farkas, G. Zhang, R. D. Ramsier, Edward A. Evans, J. A. Dagata
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
ZrNx films are deposited by rf magnetron sputtering using a wide range of nitrogen flow rates to control film properties. Scanned probe microscope (SPM) oxidation is presented as a complimentary characterization tool to x-ray diffraction, colorimetric, and four point probe analyses. The SPM oxidation behavior of the ZrNx films is related to their structural, optical, and electrical properties. Whereas stoichiometric ZrN films have applications as protective and/or decorative coatings, ZrNx films sputtered with higher nitrogen flow rates have potential applications in devices where arrays of high aspect ratio nanostructures would be useful. (C) 2008 American Vacuum Society.
Modeling, Simulation, And Experiments Of Coating Growth On Nanofibers, C. B. Clemons, P. Hamrick, J. Heminger, K. L. Kreider, G. W. Young, A. Buldum, Edward A. Evans, G. Zhang
Modeling, Simulation, And Experiments Of Coating Growth On Nanofibers, C. B. Clemons, P. Hamrick, J. Heminger, K. L. Kreider, G. W. Young, A. Buldum, Edward A. Evans, G. Zhang
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
This work is a comparison of modeling and simulation results with experiments for an integrated experimental/modeling investigation of a procedure to coat nanofibers and core-clad nanostructures with thin film materials using plasma enhanced physical vapor deposition. In the experimental effort, electrospun polymer nanofibers are coated with metallic materials under different operating conditions to observe changes in the coating morphology. The modeling effort focuses on linking simple models at the reactor level, nanofiber level and atomic level to form a comprehensive model. The comprehensive model leads to the definition of an evolution equation for the coating free surface around an isolated …
Electrical, Structural, And Chemical Properties Of Semiconducting Metal Oxide Nanofiber Yarns, A. F. Lotus, E. T. Bender, E. A. Evans, R. D. Ramsier, D. H. Reneker, George G. Chase
Electrical, Structural, And Chemical Properties Of Semiconducting Metal Oxide Nanofiber Yarns, A. F. Lotus, E. T. Bender, E. A. Evans, R. D. Ramsier, D. H. Reneker, George G. Chase
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
The electrical, structural, and chemical properties of twisted yarns of metal-oxide nanofibers, fabricated using a modified electrospinning technique, are investigated in this report. In particular, synthesized zinc oxide and nickel oxide yarns having diameters in the range of 4-40 mu m and lengths up to 10 cm were characterized, whose constituent nanofibers had average diameters of 60-100 nm. These yarns have one macroscopic dimension for handling while retaining some of the properties of nanofibers. (C) 2008 American Institute of Physics.
Synthesis And Characterization Of Erbia Doped Metal Oxide Nanofibers For Applications In The Rmophotovoltaics, E. T. Bender, R. Wang, M. T. Aljarrah, Edward A. Evans, R. D. Ramsier
Synthesis And Characterization Of Erbia Doped Metal Oxide Nanofibers For Applications In The Rmophotovoltaics, E. T. Bender, R. Wang, M. T. Aljarrah, Edward A. Evans, R. D. Ramsier
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
Titania (TiO2) nanofibers doped with erbia (Er2O3) have been synthesized by electrospinning mixtures of polymers, titanium-containing materials, and erbia particles. These electrospun nanofibers are subsequently annealed at temperatures of 800, 900, 1000, and 1050 degrees C to remove the organics and leave behind the metal oxides. The crystal structure and optical properties of the metal oxides depend on the annealing temperature, and we characterize these nanofibers using x-ray diffraction and Fourier transform infrared spectroscopy (FTIR). An Er2Ti2O7 phase is formed in an amount which depends on the annealing temperature, and relationships between the nature of FTIR spectra and the relative …
High-Voltage Parallel Writing On Iron Nitride Thin Films, N. Farkas, J. D. Ehrman, Edward A. Evans, R. D. Ramsier, J. A. Dagata
High-Voltage Parallel Writing On Iron Nitride Thin Films, N. Farkas, J. D. Ehrman, Edward A. Evans, R. D. Ramsier, J. A. Dagata
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
We report large area patterning of sputter-deposited FeN thin films by a high-voltage parallel writing technique that was recently developed to modify ZrN surfaces. Systematically patterned 15-100-nm-thick FeN films consisting of features with well-defined sizes and shapes are obtained by applying high dc voltages between a stamp and the samples. During the process the oxide dissolves, exposing the substrate beneath. This controlled breakdown eliminates the need for any postexposure etching. The single-step imprinting method presented here provides an emerging route to fabricate isolated FeN geometrical structures on silicon substrates for magnetic applications. (c) 2006 American Vacuum Society.
Dynamic Contact Angle In Rim Instability Of Dewetting Holes, Sung-Hwan Choi, Bi-Min Zhang Newby
Dynamic Contact Angle In Rim Instability Of Dewetting Holes, Sung-Hwan Choi, Bi-Min Zhang Newby
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
The effects of dynamic contact angle (theta(d)), between a substrate and the melt of a dewetting polymer thin film, on the evolution of rim instabilities of dewetting holes were reported. Various theta(d)'s were achieved by covering SiOx surfaces with different coverage of octadecyltrichlorosilane. On each surface, the morphology of the dewetting holes was examined in detail as the hole grew to a certain size. Rim instabilities, in terms of undulations in both r and z directions, became more pronounced as theta(d) increased, under which condition, narrower and higher rims were also observed. Experimentally, atomic force microscopic scans of the rim …
Multiscale Modeling, Simulations, And Experiments Of Coating Growth On Nanofibers. Part Ii. Deposition, A. Buldum, C. B. Clemons, L. H. Dill, K. L. Kreider, G. W. Young, X. Zheng, Edward A. Evans, G. Zhang, S. I. Hariharan
Multiscale Modeling, Simulations, And Experiments Of Coating Growth On Nanofibers. Part Ii. Deposition, A. Buldum, C. B. Clemons, L. H. Dill, K. L. Kreider, G. W. Young, X. Zheng, Edward A. Evans, G. Zhang, S. I. Hariharan
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
This work is Part II of an integrated experimental/modeling investigation of a procedure to coat nanofibers and core-clad nanostructures with thin-film materials using plasma-enhanced physical vapor deposition. In the experimental effort, electrospun polymer nanofibers are coated with aluminum materials under different operating conditions to observe changes in the coating morphology. This procedure begins with the sputtering of the coating material from a target. Part I [J. Appl. Phys. 98, 044303 (2005)] focused on the sputtering aspect and transport of the sputtered material through the reactor. That reactor level model determines the concentration field of the coating material. This field serves …
Multiscale Modeling, Simulations, And Experiments Of Coating Growth On Nanofibers. Part I. Sputtering, A. Buldum, I. Busuladzic, C. B. Clemons, L. H, Dill, K. L. Kreider, G. W. Young, Edward A. Evans, G. Zhang, S. I. Hariharan, W. Kiefer
Multiscale Modeling, Simulations, And Experiments Of Coating Growth On Nanofibers. Part I. Sputtering, A. Buldum, I. Busuladzic, C. B. Clemons, L. H, Dill, K. L. Kreider, G. W. Young, Edward A. Evans, G. Zhang, S. I. Hariharan, W. Kiefer
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
This paper is Part I of an integrated experimental/modeling investigation of a procedure to coat nanofibers and core-clad nanostructures with thin-film materials using plasma-enhanced physical vapor deposition. In the experimental effort, electrospun polymer nanofibers are coated with aluminum under varying operating conditions to observe changes in the coating morphology. This procedure begins with the sputtering of the coating material from a target. This paper focuses on the sputtering process and transport of the sputtered material through the reactor. The interrelationships among the processing factors for the sputtering and transport are investigated from a detailed modeling approach that describes the salient …
Spm Oxidation And Parallel Writing On Zirconium Nitride Thin Films, N. Farkas, J. R. Comer, G. Zhang, Edward A. Evans, R. D. Ramsier, J. A. Dagata
Spm Oxidation And Parallel Writing On Zirconium Nitride Thin Films, N. Farkas, J. R. Comer, G. Zhang, Edward A. Evans, R. D. Ramsier, J. A. Dagata
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
Systematic investigation of the SPM oxidation process of sputter-deposited ZrN thin films is reported. During the intrinsic part of the oxidation, the density of the oxide increases until the total oxide thickness is approximately twice the feature height. Further oxide growth is sustainable as the system undergoes plastic flow followed by delamination from the ZrN-silicon interface keeping the oxide density constant. ZrN exhibits superdiffusive oxidation kinetics in these single tip SPM studies. We extend this work to the fabrication of parallel oxide patterns 70 nm in height covering areas in the square centimeter range. This simple, quick, and well-controlled parallel …
Parallel Writing On Zirconium Nitride Thin Films By Local Oxidation Nanolithography, N. Farkas, J. R. Comer, G. Zhang, Edward A. Evans, R. D. Ramsier, S. Wight, J. A. Dagata
Parallel Writing On Zirconium Nitride Thin Films By Local Oxidation Nanolithography, N. Farkas, J. R. Comer, G. Zhang, Edward A. Evans, R. D. Ramsier, S. Wight, J. A. Dagata
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
Parallel pattern transfer of submicrometer-scale oxide features onto zirconium nitride thin films is reported. The oxidation reaction was verified by Auger microprobe analysis and secondary ion mass spectrometry. Oxide features of similar to70 nm in height can be formed and selectively etched in a dilute aqueous hydrogen fluoride solution. This provides an interesting route to potential new applications for high-melting point, biocompatible surfaces that possess small feature sizes with controlled geometries. (C) 2004 American Institute of Physics.
Local Oxidation Of Metal And Metal Nitride Films, N Farkas, J. C. Tokash, G. Zhang, Edward A. Evans, R. D. Ramsier, J. A. Dagata
Local Oxidation Of Metal And Metal Nitride Films, N Farkas, J. C. Tokash, G. Zhang, Edward A. Evans, R. D. Ramsier, J. A. Dagata
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
Oxide growth on sputter-deposited thin films is studied on the local scale by atomic force microscope (AFM)-assisted lithography. We investigate the group IV reactive metals Zr, Hf, Ti, and their nitrides.-The nitrogen content of the deposition plasma affects the film crystal structure and electrical resistivity, which in turn alter the local oxidation rates. Mass transport plays an important role, producing features with heights ranging from a few nanometers up to hundreds of nanometers. The heights of the largest features are one to two orders of magnitude greater than observed in other material systems, and the growth is well controlled. We …
Aerobic Denitrification Of Pseudomonas Aeruginosa Monitored By Online Nad(P)H Fluorescence, Fan Chen, Qing Xia, Lu-Kwang Ju
Aerobic Denitrification Of Pseudomonas Aeruginosa Monitored By Online Nad(P)H Fluorescence, Fan Chen, Qing Xia, Lu-Kwang Ju
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
Continuous cultures of Pseudomonas aeruginosa (ATCC 9027) maintained at different dissolved oxygen concentrations (DO) were studied for the effects of DO on various culture properties, especially aerobic respiration and denitrification. The DO was varied from 0 mg/liter (completely anoxic conditions) to 1.3 mg/liter and measured with optical sensors that could accurately determine very low DO based on oxygen-quenched luminescence. The strain was found to perform aerobic denitrification; while the specific rate decreased with increasing DO, denitrification persisted at approximately 1/8 of the maximum rate (1.7 mmol/g of cells/h) even at relatively high DO (1 to 1.3 mg/liter). In the presence …
High-Temperature Fiber Matrices: Electrospinning And Rare-Earth Modification, W. Kataphinan, R. Teye-Mensah, Edward A. Evans, R. D. Ramsier, D. H. Reneker, D. J. Smith
High-Temperature Fiber Matrices: Electrospinning And Rare-Earth Modification, W. Kataphinan, R. Teye-Mensah, Edward A. Evans, R. D. Ramsier, D. H. Reneker, D. J. Smith
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
We demonstrate the production of nonwoven mats of high-temperature organic and inorganic fibers by electrospinning. Specifically, glass/ceramic (tetraethylorthosilicate-SiO) and fire-blanket (polydiphenoxyphosphazene-PDPP) precursors are electrospun, and the resulting fibers are characterized by scanning electron microscopy, thermogravimetric analysis, and infrared (IR) spectroscopy. We find that the SiO fibers are smaller in diameter and more uniform than the PDPP fibers, and stable to higher temperatures. We also coat these fiber systems with several rare-earth nitrates, and find that these coatings can be used to selectively modify the near-IR spectra of the fibers. This work extends the use of electrospinning into two new classes …
Nanoscale Oxidation Of Zirconium Surfaces: Kinetics And Mechanisms, N. Farkas, G. Zhang, Edward A. Evans, R. D. Ramsier, J. A. Dagata
Nanoscale Oxidation Of Zirconium Surfaces: Kinetics And Mechanisms, N. Farkas, G. Zhang, Edward A. Evans, R. D. Ramsier, J. A. Dagata
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
We show that atomic force microscope-induced oxide features can be formed reproducibly on both Zr and ZrN surfaces, and that the growth rate decreases rapidly with increasing time. There is an increase in oxide-feature height with humidity for both systems, and an approximately linear dependence of the height of the structures on the applied voltage for all films for short exposure times. As the anodization time increases, only the thinnest (6 nm) films show a large enhancement in oxide-feature height, demonstrating the role of the film/substrate interface. Under the same conditions, the height of features grown on ZrN films is …
Poly(Meta-Phenylene Isophthalamide) Nanofibers: Coating And Post Processing, Wenxia Liu, Matthew Graham, Edward A. Evans, Darrell H. Reneker
Poly(Meta-Phenylene Isophthalamide) Nanofibers: Coating And Post Processing, Wenxia Liu, Matthew Graham, Edward A. Evans, Darrell H. Reneker
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
Electrospun nanofibers have applications in the areas of filtration, composites; biomaterials, and electronics. Controlling the surface properties of these nanofibers is important for many applications. Nanofibers can also be used as unique substrates for observing the growth of deposited films and creating nanoscale structures. In this work, electrospun poly(meta-phenylene isophthalamide) (MPD-I) nanofibers were used as substrates for creating nanoscale structures out of carbon-based materials and metals. MPD-I was used because it can be electrospun into nanofibers with diameters smaller than 10 nm and it has good thermal stability. MPD-I nanofibers were coated with carbon, copper, and aluminum using plasma enhanced …
Two-Phase Decay Of Aerobic Sludge Shown By Online Fluorescence And Modeled With Interaction Of Heterotrophs And Nitrifiers, Xu Li, Lu-Kwang Ju
Two-Phase Decay Of Aerobic Sludge Shown By Online Fluorescence And Modeled With Interaction Of Heterotrophs And Nitrifiers, Xu Li, Lu-Kwang Ju
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
Both heterotrophs and autotrophic nitrifiers are present in aerobic sludge digestion systems. The endogenous heterotrophic metabolism releases ammonium that, via oxidation to nitrite and nitrate, serves as the energy substrate for growth and survival of nitrifiers. The population interaction was used to explain the two-phase decay behavior observed in this study for the biosolids collected from rotating biological contactors (RBC) as well as the mixed primary and secondary sludge. Separated by an intermediate transition, the two phases followed different first-order decay kinetics, with the first phase being much faster. The two-phase phenomenon was supported by the on-line fluorescence profile monitored …
Degradation Of N-Hexadecane And Its Metabolites By Pseudomonas Aeruginosa Under Microaerobic And Anaerobic Denitrifying Conditions, Chawala Chayabutra, Lu-Kwang Ju
Degradation Of N-Hexadecane And Its Metabolites By Pseudomonas Aeruginosa Under Microaerobic And Anaerobic Denitrifying Conditions, Chawala Chayabutra, Lu-Kwang Ju
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
A strategy for sequential hydrocarbon bioremediation is proposed. The initial O-2-requiring transformation is effected by aerobic resting cells, thus avoiding a high oxygen demand. The oxygenated metabolites can then be degraded even under anaerobic conditions when supplemented with a highly water-soluble alternative electron acceptor, such as nitrate. To develop the new strategy, some phenomena were studied by examining Pseudomonas aeruginosa fermentation. The effects of dissolved oxygen (DO) concentration on n-hexadecane biodegradation were investigated first. Under microaerobic conditions, the denitrification rate decreased as the DO concentration decreased, implying that the O-2-requiring reactions were rate limiting. The effects of different nitrate and …
Hybrid Reflection-Transmission Surface Light-Scattering Instrument With Reduced Sensitivity To Surface Sloshing, William V. Meyer, James A. Lock, Michael Cheung, Thomas W. Taylor, Padetha Tin, J. Adin Mann Jr.
Hybrid Reflection-Transmission Surface Light-Scattering Instrument With Reduced Sensitivity To Surface Sloshing, William V. Meyer, James A. Lock, Michael Cheung, Thomas W. Taylor, Padetha Tin, J. Adin Mann Jr.
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
A hybrid reflection-transmission surface light-scattering instrumental design is presented, examined theoretically, and tested experimentally. The purpose of the design is to reduce the sensitivity of the instrument to vibration in general and surface sloshing in particular while sacrificing Little performance. Traditional optical arrangements and two new optical configurations with varying trade-offs between slosh resistance and instrumental simplicity and accuracy are examined by use of Fourier optics methods. The most promising design was constructed and tested with acetone, ethanol, and water as subject fluids. The test involved backcalculation of the wave number of the capillary wave examined with the known physical …
Microemulsion Characterization By The Use Of A Noninvasive Backscatter Fiber Optic Probe, Rafat R. Ansari, Harbans S. Dhadwal, Michael Cheung, William V. Meyer
Microemulsion Characterization By The Use Of A Noninvasive Backscatter Fiber Optic Probe, Rafat R. Ansari, Harbans S. Dhadwal, Michael Cheung, William V. Meyer
Chemical, Biomolecular, and Corrosion Engineering Faculty Research
This paper demonstrates the utility of a noninvasive backscatter fiber optic probe for dynamic light-scattering characterization of a microemulsion comprising sodium dodecyl sulfate/1-butanol/brine/heptane. The fiber probe, comprising two optical fibers precisely positioned in a stainless steel body, is a miniaturized and efficient self-beating dynamic light-scattering system. Accuracy of particle size estimation is better than +/- 2%.