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A Label-Free High Throughput Resistive-Pulse Sensor For Simultaneous Differentiation And Measurement Of Multiple Particle-Laden Analytes, Ashish Jagtiani, Rupesh Sawant, Jiang Zhe Apr 2015

A Label-Free High Throughput Resistive-Pulse Sensor For Simultaneous Differentiation And Measurement Of Multiple Particle-Laden Analytes, Ashish Jagtiani, Rupesh Sawant, Jiang Zhe

Dr. Jiang Zhe

We describe an all-electronic, label-free, resistive-pulse sensor that utilizes multiple microchannels for parallel detection, counting and differentiation of multiple biological particles simultaneously. Four particle solutions, including 20 µm and 40 µm polymethacrylate particles, Juniper Scopulorum (Rocky Mountain Juniper) pollen and Populus deltidoes (Eastern Cottonwood) pollen, were loaded to the four peripheral reservoirs, respectively, and were driven to the central reservoir through four microchannels, all operating simultaneously for particle detection and counting. Experiments demonstrated that this sensor was able to differentiate and count multiple particle solutions simultaneously through its four microchannels fabricated on polymer membranes. Thus the sensing throughput has been …


Swelling Characteristics Of Acrylic Acid Polyelectrolyte Hydrogel In A Dc Electric Field, Esmaiel Jabbari, Javad Tavakoli, Alireza Sarvestani Jan 2015

Swelling Characteristics Of Acrylic Acid Polyelectrolyte Hydrogel In A Dc Electric Field, Esmaiel Jabbari, Javad Tavakoli, Alireza Sarvestani

Esmaiel Jabbari

No abstract provided.


Polymer Based Nanocomposites With Nanofibers And Exfoliated Clay, Michael Meador, Darrell Reneker Jul 2014

Polymer Based Nanocomposites With Nanofibers And Exfoliated Clay, Michael Meador, Darrell Reneker

Darrell Hyson Reneker

Polymer solutions, containing clay sheets, were electrospun into nanofibers and microfibers that contained clay sheets inside. Controllable removal of polymer by plasma etching from the surface of fibers revealed the arrangement of clay. The shape, flexibility, size distribution and arrangement of clay sheets were observed by transmission and scanning electron microscopy. The clay sheets were partially aligned in big fibers with normal direction of clay sheets perpendicular to fiber axis. Crumpling of clay sheets inside fibers was observed when the fiber diameter was comparable to the lateral size of clay sheets. Single sheets of clay were observed both by catching …


Spectroscopic Investigation Into Oxidative Degradation Of Silica-Supported Amine Sorbents For Co2 Capture, Chakravartula Srikanth, Steven Chuang Jul 2014

Spectroscopic Investigation Into Oxidative Degradation Of Silica-Supported Amine Sorbents For Co2 Capture, Chakravartula Srikanth, Steven Chuang

Steven S.C. Chuang

Oxidative degradation characteristics of silica-supported amine sorbents with varying amounts of tetraethylenepentamine (TEPA) and polyethylene glycol (PEG; P200 or P600 represents PEG with molecular weights of 200 or 600) have been studied by IR and NMR spectroscopy. Thermal treatment of the sorbents and liquid TEPA at 100 °C for 12 h changed their color from white to yellow. The CO2 capture capacity of the TEPA/SiO2 sorbents (i.e., SiO2-supported TEPA with a TEPA/SiO2 ratio of 25:75) decreased by more than 60 %. IR and NMR spectroscopy studies showed that the yellow color of the degraded sorbents resulted from the formation of …


Application Of The Thermal Flash Technique For Low Thermal Diffusivity Micro/Nanofibers, Michael T. Demko, Zhenting Dai, Han Yan, William P. King, Miko Cakmak, Alexis R. Abramson Apr 2014

Application Of The Thermal Flash Technique For Low Thermal Diffusivity Micro/Nanofibers, Michael T. Demko, Zhenting Dai, Han Yan, William P. King, Miko Cakmak, Alexis R. Abramson

Mukerrem Cakmak

The thermal flash method was developed to characterize the thermal diffusivity of micro/nanofibers without concern for thermal contact resistance, which is commonly a barrier to accurate thermal measurement of these materials. Within a scanning electron microscope, a micromanipulator supplies instantaneous heating to the micro/nanofiber, and the resulting transient thermal response is detected at a microfabricated silicon sensor. These data are used to determine thermal diffusivity. Glass fibers of diameter 15 mu m had a measured diffusivity of 1.21x10(-7) m(2)/s; polyimide fibers of diameters 570 and 271 nm exhibited diffusivities of 5.97x10(-8) and 6.28x10(-8) m(2)/s, respectively, which compare favorably with bulk …


Free Radicals Copolymerization Optimization, System: Acrylonitrile-Vinyl Acetate In Cstr, Silvia V. Vallecillo-Gomez, Juan C. Tapia-Picazo, Adrian Bonilla-Petriciolet, Gibran G. De-Alba-Perez-De-Gracia Jan 2011

Free Radicals Copolymerization Optimization, System: Acrylonitrile-Vinyl Acetate In Cstr, Silvia V. Vallecillo-Gomez, Juan C. Tapia-Picazo, Adrian Bonilla-Petriciolet, Gibran G. De-Alba-Perez-De-Gracia

Adrian Bonilla-Petriciolet

In this work, we study the free radicals solution copolymerization, system acrylonitrile (AN) – vinyl acetate (VA), with the objective to find the parameters of characteristic correlations that are used to determine the reaction autoacceleration phenomenon or gel effect. Two gel effect correlations were evaluated for each monomer. Parameters were found using the stochastic global optimization Simulated Annealing method and experimental data in batch reactor. Gel effect correlations with greater adjustment were used to carry out a sensitivity analysis through continuous stirred tank reactor model. A competence between monomers conversion, average molecular weight of the polymer and the polidispersity was …


Energetic And Entropic Elasticity Of Nonisothermal Flowing Polymers: Experiment, Theory, And Simulation, David Keffer, T. C. Ionescu, B. J. Edwards, V. G. Mavrantzas Jan 2008

Energetic And Entropic Elasticity Of Nonisothermal Flowing Polymers: Experiment, Theory, And Simulation, David Keffer, T. C. Ionescu, B. J. Edwards, V. G. Mavrantzas

David Keffer

The thermodynamical aspects of polymeric liquids subjected to nonisothermal flow are examined from the complementary perspectives of theory, experiment, and simulation. In particular, attention is paid to the energetic effects, in addition to the entropic ones, that occur under conditions of extreme deformation. Comparisons of experimental measurements of the temperature rise generated under elongational flow at high strain rates with macroscopic finite element simulations offer clear evidence of the persistence and importance of energetic effects under severe deformation. The performance of various forms of the temperature equation are evaluated with regard to experiment, and it is concluded that the standard …


Phase Behavior In Copolymer Blends Of Poly(P-Chlorostyrene-Co-O-Chlorostyrene) And Phenylsulfonylated Poly(2,6-Dimethyl-1,4-Phenylene Oxide), William Macknight, R. Vukovic, G. Bogdanic, Vjera Kuresevic, M. Tomaskovic, F. E. Karasz Dec 1993

Phase Behavior In Copolymer Blends Of Poly(P-Chlorostyrene-Co-O-Chlorostyrene) And Phenylsulfonylated Poly(2,6-Dimethyl-1,4-Phenylene Oxide), William Macknight, R. Vukovic, G. Bogdanic, Vjera Kuresevic, M. Tomaskovic, F. E. Karasz

William MacKnight

The miscibility of random copolymers of o-chlorostyrene and p -chlorostyrene [ P (oC1Stco-
pC1St)] with partially phenylsulfonylated poly (2,6-dimethyl-1,4-phenylenoex ide)
( SPPO) copolymers has been studied, using differential scanning calorimetry (DSC) to
establish Tg behavior. It already has been established that the isomeric effect of the chlorine
substitution on miscibility is large. Thus the para-chloro-substituted styrenic homopolymer
is miscible with all SPPOs containing more than - 5 mol % phenylsulfonylation, whereas
the ortho-chloro-substituted homopolymer is immiscible with the entire range of SPPO
copolymer compositions (and also with the respective homopolymers) . As a result of this
asymmetric behavior of the …


Thermodynamic Aging Of Immiscible Polymer Blends, William Macknight, Ronald Koningsveld, Karel Sole Dec 1992

Thermodynamic Aging Of Immiscible Polymer Blends, William Macknight, Ronald Koningsveld, Karel Sole

William MacKnight

No abstract provided.


Molecular Motions In Model Network Polymers, William Macknight, L. Charles Dickinson, P. Morganelli, C. W. Chu, Z. Petrovic, James C. W. Chien Dec 1987

Molecular Motions In Model Network Polymers, William Macknight, L. Charles Dickinson, P. Morganelli, C. W. Chu, Z. Petrovic, James C. W. Chien

William MacKnight

No abstract provided.


Structure And Applications Of Ion-Containing Polymers, William Macknight Dec 1985

Structure And Applications Of Ion-Containing Polymers, William Macknight

William MacKnight

No abstract provided.


Deformation Studies Of Polymers By Time-Resolved Infrared Spectroscopy Iv: A Modified Approach, William Macknight, S. E. Moles, S. L. Hsu Dec 1983

Deformation Studies Of Polymers By Time-Resolved Infrared Spectroscopy Iv: A Modified Approach, William Macknight, S. E. Moles, S. L. Hsu

William MacKnight

No abstract provided.


A Comment On The T.... Relaxation As Observed In Polymers By Means Of Thermally Stimulated Current (Tsc) Measurements, William Macknight, R. M. Neumann Dec 1980

A Comment On The T.... Relaxation As Observed In Polymers By Means Of Thermally Stimulated Current (Tsc) Measurements, William Macknight, R. M. Neumann

William MacKnight

No abstract provided.


Thermal Degradation Of Glumate Polymers, William Macknight, C. Peter Lillya, Richard M. Newman, Wei-Fang A. Su, Peter C. Uden Dec 1979

Thermal Degradation Of Glumate Polymers, William Macknight, C. Peter Lillya, Richard M. Newman, Wei-Fang A. Su, Peter C. Uden

William MacKnight

No abstract provided.


Poly(Alkyl Alpha-Chloroacrylates). V. Preparation And Properties Of Methyl, Ethyl, And Isopropyl Polymers Of Varied Tacticity, William Macknight, G. R. Dever, F. E. Karasz, R. W. Lenz Dec 1974

Poly(Alkyl Alpha-Chloroacrylates). V. Preparation And Properties Of Methyl, Ethyl, And Isopropyl Polymers Of Varied Tacticity, William Macknight, G. R. Dever, F. E. Karasz, R. W. Lenz

William MacKnight

No abstract provided.


Relaxation Of Disulfide And Tetrasulfide Polymers, William Macknight, A. V. Tobolsky, M. Takahashi Dec 1963

Relaxation Of Disulfide And Tetrasulfide Polymers, William Macknight, A. V. Tobolsky, M. Takahashi

William MacKnight

The chemorheology of cross-linked polyethylene disulfide, polyethylene tetrasulfide, and mixtures of these polymers with elemental sulfur is investigated. It is shown that stress decay in the disulfide polymer occurs by scission of the small quantities of higher poly­sulfide linkages present in the network. It is also shown that elemental sulfur decreases the chemical relaxation time in cross-linked polyethylene disulfide in a predictable manner.