Engineering Commons^™

Osaka University: A Focus Of Polymer Science: 70th Anniversary Celebration, Otto Vogl, Koichi Hatada

Emeritus Faculty Author Gallery

No abstract provided.

Personalities In Polymer Science: Cover Page, Title Page, Introduction, And List Of Articles, Otto Vogl

Emeritus Faculty Author Gallery

A compilation of articles with short biographies of the scientists who played leading roles in the field and provided the basis of Polymer Science and Technology throughout the 20th century.

Poly(Meta-Phenylene Isophthalamide) Nanofibers: Coating And Post Processing, Wenxia Liu, Mathew Graham, Edward A. Evans, Darrell Hyson Reneker

College of Polymer Science and Polymer Engineering

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 …

The Effect Of Convection On Disorder In Primary Cellular And Dendritic Arrays, R. Trivedi, P. Mazumder, Surendra N. Tewari

Chemical & Biomedical Engineering Faculty Publications

Directional solidification studies have been carried out to characterize the spatial disorder in the arrays of cells and dendrites. Different factors that cause array disorder are investigated experimentally and analyzed numerically. In addition to the disorder resulting from the fundamental selection of a range of primary spacings under given experimental conditions, a significant variation in primary spacings is shown to occur in bulk samples due to convection effects, especially at low growth velocities. The effect of convection on array disorder is examined through directional solidification studies in two different alloy systems, Pb-Sn and Al-Cu. A detailed analysis of the spacing …

1. Yukio Imanishi, Otto Vogl

Emeritus Faculty Author Gallery

No abstract provided.

Acquisition Of Laser Scanning Confocal Microscope For Biological And Materials Research, Stephen M. Shaler, Seth Shaler, Susan Brawley, Carol H. Kim, Paul J. Millard

University of Maine Office of Research Administration: Grant Reports

Biological and Materials research at the University of Maine will be strongly impacted by the acquisition of a Laser Scanning Electron Microscope as a result of this NSF-MRI award. The Leica confocal unit, along with an upright and inverted microscope and digital camera will form a multi-user facility for campus researchers working with a range of biological and materials problems. Initially, 13 faculty members from 8 academic departments have projects planned for the instrument. The microscope will be the first of its kind on the University of Maine campus.

A wide range of research problems will be attacked through use …

2. Toshinobu Higashimura, Otto Vogl

Emeritus Faculty Author Gallery

No abstract provided.

An Approach To Sequence Dna Without Tagging, Sanjun Niu, Ravi F. Saraf

Papers in Biotechnology

Microarray technology is playing an increasingly important role in biology and medicine and its application to genomics for gene expression analysis has already reached the market with a variety of commercially available instruments. In these combinatorial analysis methods, known probe single-strand DNA (ssDNA) ‘primers’ are attached in clusters of typically 100 μm × 100 μm pixels. Each pixel of the array has a slightly different sequence. On exposure to ‘unknown’ target ssDNA, the pixels with the right complementary probe ssDNA sequence convert to double-stranded DNA (dsDNA) by a hybridization reaction. To transduct the conversion of the pixel to dsDNA, the …

3. Otto Vogl, Gerald S. Kirshenbaum, Helga Roder

Emeritus Faculty Author Gallery

No abstract provided.

Microbial Cellulose Utilization: Fundamentals And Biotechnology, Lee R. Lynd, Paul J. Weimer, Willem H. Van Zyl, Isak S. Pretorius

Dartmouth Scholarship

Fundamental features of microbial cellulose utilization are examined at successively higher levels of aggregation encompassing the structure and composition of cellulosic biomass, taxonomic diversity, cellulase enzyme systems, molecular biology of cellulase enzymes, physiology of cellulolytic microorganisms, ecological aspects of cellulase-degrading communities, and rate-limiting factors in nature. The methodological basis for studying microbial cellulose utilization is considered relative to quantification of cells and enzymes in the presence of solid substrates as well as apparatus and analysis for cellulose-grown continuous cultures. Quantitative description of cellulose hydrolysis is addressed with respect to adsorption of cellulase enzymes, rates of enzymatic hydrolysis, bioenergetics of microbial …

Accurate Quantification Of Steady And Pulsatile Flow With Segmented K-Space Magnetic Resonance Velocimetry, Haosen Zhang, Sandra S. Halliburton, James R. Moore, Orlando P. Simonetti, Paulo R. Schvartzman, Richard D. White, George P. Chatzimavroudis

Chemical & Biomedical Engineering Faculty Publications

Conventional non-segmented magnetic resonance phase velocity mapping (MRPVM) is an accurate but relatively slow velocimetric technique. Therefore, the aim of this study was to evaluate the accuracy of the much faster segmented k-space MRPVM in quantifying flow. The axial velocity was measured in four straight tubes (inner diameter: 5.6–26.2 mm), using a segmented MRPVM sequence with seven lines of k-space per segment. The flow rate and flow volume were accurately quantified (errorssteady (r²=0.99) and pulsatile flow (r²=0.98), respectively. The measured velocity profiles and flow rates from the segmented sequence agreed …

Electrically-Small Low Q Radiator Structure And Method Of Producing Em Waves Therewith, Craig A. Grimes, Dale M. Grimes, Faton Tefiku, Gang Lui

Chemical and Materials Engineering Faculty Patents

An electrically small radiator structure for radiating electromagnetic waves having an electrical size, k*a, with a value less than π/2 and above π/20,000 and configured to have at least a first and second magnetic, or electric, dipole element. Dipole elements are preferably oriented such that a source-associated standing energy value for the structure, or W_ds(t_R), is low, Radiative Q value preferably less than ⅓(k*a)³; and each of the elements, whether paired with respective electric dipole elements, is in electrical communication through a feed circuit to at least one power source. Further, a first …

Poly (1-Trimethysilyl-1-Propyne) Membrane Regeneration Process, Andrei G. Fadeev, Michael M. Meagher

Department of Chemical and Biomolecular Engineering: Faculty Publications

A novel process for the regeneration of PTMSP membranes is disclosed. The regeneration process includes washing a fouled PTMSP membrane with a solution containing at least about 50% butanol in water for a time sufficient to increase the flux and/or selectivity of the membrane. This regeneration process with a butanol containing solution significantly improves both the flux and selectivity of the PTMSP membrane and can regenerate the flux of the PTMSP membrane to the level of a previously unused membrane.

Fluoride Release From Model Glass Ionomer Cements, A. Guida, R. G. Hill, Mark R. Towler, S. Eramo

Chemical and Biochemical Engineering Faculty Research & Creative Works

Glass ionomer cements (GICs) are an important class of biomedical material used extensively for color matched mercury free, dental restorations. GICs can release clinically beneficial amounts of fluoride and have acceptable handling properties which make them suitable as dental restoratives. The fluoride release of model GICs produced from specially synthesized fluoro-alumino-silicate glasses was studied. Nine glasses of varying fluoride content based on 4.5SiO₂-3Al₂O₃-1.5P₂O₅-(5-Z)CaO-ZCaF₂ were synthesized, and cement disks were prepared from them. The glass transition temperature reduced with increasing fluorine content of the glass. Fluoride ion release was measured …

A Preliminary Study Of An Aluminum-Free Glass Polyalkenoate Cement, Mark R. Towler, C. M. Crowley, D. Murphy, A. M.C. O'Callaghan

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

A Device For Surface Study Of Confined Micron Thin Films In A Total Internal Reflection Geometry, Sergey Mamedov, Alexander D. Schwab, Ali Dhinojwala

College of Polymer Science and Polymer Engineering

A device to probe the molecular structure of materials next to a solid interface in a thin film geometry has been developed. The device can produce controlled thicknesses as small as 1 mum with parallelity better than 0.003degrees. We have shown that the thickness and the parallelity of the film produced between two optical surfaces can be quantified using white light and monochromatic light interferometry, respectively. In addition, this apparatus allows the study of these films in a static state or under shear using spectroscopic techniques involving transmission or reflection measurements. (C) 2002 American Institute of Physics.

Nano-Devices Using Block-Copolymers, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A structure including a substrate. A first electrode and a second electrode are arranged spaced apart from each other on the substrate. A polymer string is positioned on the substrate between the two electrodes, the polymer line has a width of less than about 50 nm.

Remote Magneto-Elastic Analyte, Viscosity And Temperature Sensing Apparatus And Associated Methods Of Sensing, Craig A. Grimes, Plamen G. Stoyanov

Chemical and Materials Engineering Faculty Patents

An analyte, viscosity, or temperature sensing apparatus for operative arrangement within a time-varying magnetic field, including a sensor with an outer surface that is chemically, frictionally, or thermally responsive and adhered to a base magnetostrictive element, and a receiver to measure a first and second value for magneto-elastic emission intensity of the sensor taken at, respectively, a first and second interrogation frequency. A change in mass or a change in material stiffness of the sensor due to the responsiveness, the viscosity and mass density of a fluid therearound, or the temperature, can be identified. The receiver, alternatively, measures a plurality …

Development Of A Model For Induction Heating, Randy Clarksean, Yitung Chen

Fuels Campaign (TRP)

There are two coupled equations that must be solved in order to determine the power deposition. The numerical solution of these equations is needed in order to apply a source term within the energy equations. These equations have previously solved in FIDAP. That implementation used modified versions of the momentum and energy equations to provide a mechanism for the solution of two coupled equations. Currently, we want to solve for the induction heating field in addition to the flow field and the energy equation. In order to do this, a mechanism has to be defined within FIDAP to solve these …

Magnetoelastic Sensing Apparatus And Method For Remote Pressure Query Of An Environment, Craig A. Grimes, Plamen G. Stoyanov, Dimitris Kouzoudis

Chemical and Materials Engineering Faculty Patents

A pressure sensing apparatus for operative arrangement within an environment, having: a sensor comprising a hermetically-sealed receptacle, at least one side of which has an flexible membrane to which a magnetically hard element is attached. Enclosed within the receptacle is a magnetostrictive element that vibrates in response to a time-varying magnetic field. Also included is a receiver to measure a plurality of successive values for magneto-elastic emission intensity of the sensor taken over an operating range of successive interrogation frequencies to identify a resonant frequency value for the sensor. Additional features include: (a) the magnetically hard element may be adhered …

Genome-Wide Screening For Trait Conferring Genes Using Dna Microarrays, R. T. Gill, S. Wildt, Y. T. Yang, S. Ziesman, G. Stephanopoulos

Dartmouth Scholarship

We report a DNA microarray-based method for genome-wide monitoring of competitively grown transformants to identify genes whose overexpression confers a specific cellular phenotype. Whereas transcriptional profiling identifies differentially expressed genes that are correlated with particular aspects of the cellular phenotype, this functional genomics approach determines genes that result in a specific physiology. This parallel gene-trait mapping method consists of transforming a strain with a genomic library, enriching the cell population in transformants containing the trait conferring gene(s), and finally using DNA microarrays to simultaneously isolate and identify the enriched gene inserts. Various methods of enrichment can be used; here, genes …

The Fission Properties Of Curium Separated From Spent Nuclear Fuel, William Culbreth, Elizabeth Bakker, Jason Viggato

Separations Campaign (TRP)

Curium poses special problems in the chemical preparation of spent nuclear fuel for transmutation. Once separated from the other minor actinides, the seven curium isotopes in spent fuel can lead to nuclear fission with the subsequent release of a large amount of radiation. Several isotopes of curium also generate a significant amount of heat by radioactive decay. Sustained fission can be avoided by preventing the accumulation by more that a critical mass of curium. The heat generation of curium presents even more restriction on the mass of curium that can safely be contained in one location.

To analyze the nuclear …

Melting At Alkyl Side Chain Comb Polymer Interfaces, K. S. Gautam, Ali Dhinojwala

College of Polymer Science and Polymer Engineering

Infrared visible sum frequency generation (SFG) spectroscopy has been used to study structure and melting transition temperatures of alkyl-side chain-acrylate comb polymers at air and solid interfaces. At the air interface, the SFG spectra show methyl bands and two transitions are observed: the first, near the bulk melting temperature, T-m, and the second 10-20degreesC higher than T-m. The shorter the alkyl side chain, the larger the difference between the two transition temperatures. In contrast, methylene bands are observed at sapphire interface with a single transition near T-m (C18).

Motion Of Droplets Along Thin Fibers With Temperature Gradient, Alexander L. Yarin, Wenxia Liu, Darrell Hyson Reneker

College of Polymer Science and Polymer Engineering

Liquid n-decane, n-undecane, n-dodecane, and n-hexadecane formed tiny symmetrical droplets on a partially wettable cylindrical fiber. When a temperature gradient was created along the fiber, the droplets began to move along the fiber toward the cold region. An explanation of the phenomenon is related to the thermocapillary motion. Other possible mechanisms were ruled out. The theoretical results and experimental data agree reasonably well. (C) 2002 American Institute of Physics.

Cfd Of Multiphase Flow In Packed-Bed Reactors: Ii. Results And Applications, Y. Jiang, M. R. Khadilkar, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

Numerical Simulations of Multiphase Flow using the K-Fluid CFD Model Described in Part I of This Issue Are Presented for Packed Beds at Various Operating Conditions. Both Steady-State and Unsteady-State (E.g., Periodic Operation) Feed Conditions Were Studied Numerically. Predictions of the K-Fluid CFD Model Are Comparable with the Experimental Data in the Literature for Liquid Upflow in a Cylindrical Packed Bed. in Addition to the Mean Porosity and the Longitudinally Averaged Radial Porosity Profile, the Variance of the Porosity Distribution is Needed for Predicting the Probability Density Function of the Sectional Flow Velocity. in the Trickling Flow Regime, the K-Fluid …

Cfd Of Multiphase Flow In Packed-Bed Reactors: I. K-Fluid Modeling Issues, Y. Jiang, M. R. Khadilkar, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Eulerian K-Fluid CFD Model Was Used to Simulate the Macroscale Multiphase Flow in Packed Beds. the Geometric Complexity of the Bed Structure is Resolved by Statistically Describing the Porosity Distribution. the Complicated Multiphase Interactions Are Computed using the Ergun Type of Formula Developed based on Bench-Scale Hydrodynamic Experiments. the Work is Presented in Two Sequential Articles. Part I Discusses Implementation Issues of the K-Fluid CFD Model for Packed Beds. the Drag Exchange Coefficients Are Obtained from the Model of Holub Et Al. for the Particle-Fluid Interfaces Xks and from the Model of Attou Et Al. (1999) for the Gas …

Thermal Analysis Of Fly Ashes Sourced From European Non-Blended Coals, Kenneth T. Stanton, Mark R. Towler, Patrick Mooney, Robert G. Hill, Xavier Querol

Chemical and Biochemical Engineering Faculty Research & Creative Works

Fly ashes exist as a mixture of major amorphous phases and minor crystalline phases. For commercial applications, such as in concretes and for the production of zeolites, it would be desirable to be able to predict the reactivity of fly ashes. The amorphous phase dominates degradation behaviour, because glasses have a higher potential energy than the equivalent crystal structure and the variation of bond angles and distances in a glass make the bond breakage easier. Despite the large quantities of fly ash produced annually by coal-burning power plants, there have been very few studies investigating the microstructure and composition of …

Remote Resonant-Circuit Analyte Sensing Apparatus With Sensing Structure And Associated Method Of Sensing, Craig A. Grimes

Chemical and Materials Engineering Faculty Patents

A resonant sensing apparatus for operative arrangement within a test environment to sense an analyte. A sensing structure is included having an antenna in electrical communication with a resonant circuit and a structural element made of a material that selectively responds to the analyte. This sensing structure will resonate at a particular characteristic resonant frequency in the presence of an applied interrogation electromagnetic field and the analyte upon the occurrence of the selective response. A receiver is used for remotely identifying a value for the characteristic resonant frequency by measuring a plurality of values for electromagnetic emission intensity of the …

Thermodynamics And Bioenergetics, Yaşar Demirel, Stanley I. Sandler

Papers in Thermal Mechanics

Bioenergetics is concerned with the energy conservation and conversion processes in a living cell, particularly in the inner membrane of the mitochondrion. This review summarizes the role of thermodynamics in understanding the coupling between the chemical reactions and the transport of substances in bioenergetics. Thermodynamics has the advantages of identifying possible pathways, providing a measure of the efficiency of energy conversion, and of the coupling between various processes without requiring a detailed knowledge of the underlying mechanisms. In the last five decades, various new approaches in thermodynamics, non-equilibrium thermodynamics and network thermodynamics have been developed to understand the transport and …

Thermodynamics And Bioenergetics, Yaşar Demirel, Stanley I. Sandler

Papers in Thermal Mechanics

Bioenergetics is concerned with the energy conservation and conversion processes in a living cell, particularly in the inner membrane of the mitochondrion. This review summarizes the role of thermodynamics in understanding the coupling between the chemical reactions and the transport of substances in bioenergetics. Thermodynamics has the advantages of identifying possible pathways, providing a measure of the efficiency of energy conversion, and of the coupling between various processes without requiring a detailed knowledge of the underlying mechanisms. In the last five decades, various new approaches in thermodynamics, non-equilibrium thermodynamics and network thermodynamics have been developed to understand the transport and …