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Articles 11311 - 11340 of 14130

Full-Text Articles in Engineering

Micro Goniometer For Scanning Probe Microscopy, Ravi F. Saraf Apr 2003

Micro Goniometer For Scanning Probe Microscopy, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A goniometer for performing scanning probe microscopy on a substrate surface is disclosed. The goniometer has a cantilever, having a cantilevered end and a supported end and a tip disposed at the cantilevered end of the cantilever. The goniometer also has a block disposed at the supported end of the cantilever. The block has at least one pair of piezoelectric layers, a pair of electrodes disposed about each individual piezoelectric layer such that varying a potential difference applied between the individual electrodes of a pair of electrodes causes the corresponding piezoelectric layer to deform, and a first insulating material disposed …


Ferroelectric Storage Read-Write Memory, Ravi F. Saraf Apr 2003

Ferroelectric Storage Read-Write Memory, Ravi F. Saraf

Department of Chemical and Biomolecular Engineering: Patents

A memory device including at least one pair of spaced apart conductors and a ferroelectric material between the pair of conductors. The pair of conductors is spaced apart a distance sufficient to permit a tunneling current there between.


Method Of Preparing A Composite Polymer And Silica-Based Membrane, Dibakar Bhattacharyya, Stephen M. Ritchie, Leonidas G. Bachas, Jamie A. Hestekin, Subhas K. Sikdar Apr 2003

Method Of Preparing A Composite Polymer And Silica-Based Membrane, Dibakar Bhattacharyya, Stephen M. Ritchie, Leonidas G. Bachas, Jamie A. Hestekin, Subhas K. Sikdar

Chemical and Materials Engineering Faculty Patents

A method for preparing a chemically activated or polyamino acid functionalized membrane includes the steps of permeating a silica-based membrane with a solution of silane and a solvent so as to react methoxy groups of the silane with silanol groups of the membrane to incorporate epoxide groups and attaching a polyamino acid to the membrane by reacting a terminal amine group of the polyamino acid with one of the epoxide groups on the membrane.


Preparing And Regenerating A Composite Polymer And Silica-Based Membrane, Dibakar Bhattacharyya, Stephen M. Ritchie, Leonidas G. Bachas, Jamie A. Hestekin, Subhas K. Sikdar Apr 2003

Preparing And Regenerating A Composite Polymer And Silica-Based Membrane, Dibakar Bhattacharyya, Stephen M. Ritchie, Leonidas G. Bachas, Jamie A. Hestekin, Subhas K. Sikdar

Chemical and Materials Engineering Faculty Patents

A method for preparing and regenerating a chemically activated or polyamino acid functionalized membrane includes the steps of permeating the silica-based membrane with a solution of silane and a solvent so as to react methoxy groups of the silane with silanol groups of the membrane to incorporate epoxide groups and attaching a polyamino acid to the membrane by reacting a terminal amine group of the polyamino acid with one of the epoxide groups on the membrane. The membrane is regenerated after metal entrapment by utilizing helix-coil properties of polyamino acids.


Investigation Into The Ultrasound Setting Of Glass Ionomer Cements. Part I. Postulated Modalities, Mark R. Towler, C. M. Crowley, R. G. Hill Apr 2003

Investigation Into The Ultrasound Setting Of Glass Ionomer Cements. Part I. Postulated Modalities, Mark R. Towler, C. M. Crowley, R. G. Hill

Chemical and Biochemical Engineering Faculty Research & Creative Works

Fuji IX glass is a low phosphate, low soda containing glass which has strontia incorporated as a radio-pacifier. This glass material was analyzed during exposure to different durations of ultrasound in an attempt to determine how the glass phase reacts. Cross sections of Fuji IX cement, set both conventionally and by ultrasound, were subsequently compared by microscopy. The resultant data were analyzed in detail.


Study About High Influence Doping To Base Resistance And Bandgap Narrowing At Si/Si1-Xgex/Si Heterojunction Bipolar Transistor, Achmad Fadhol Apr 2003

Study About High Influence Doping To Base Resistance And Bandgap Narrowing At Si/Si1-Xgex/Si Heterojunction Bipolar Transistor, Achmad Fadhol

Makara Journal of Technology

Study About High Influence Doping to Base Resistance and Bandgap Narrowing at Si/Si1-xGex/Si Heterojunction Bipolar Transistor. Heterojunction is a link formed bedween two semiconductor materials and differend bandgap which has thinness under 50nm and grow the mixture of plate SiGe as bases. The link is an abrupt link or graded one. In this research learnt formulation of doping concentration influence to basis resistance and bandgap narrowing through Si/Si1-xGex/Si Heterojunction Bipolar Transistor with abrupt emitter-basis link, besides taking care to mobility and basis wide to basis resistance, it is also influence of mole fraction to bandgap power. From the result shows …


Photocatalytic Treatment Of Heavy Metal Waste Cr(Vi) Withtio2 Photocatalyst, Slamet Slamet, Riyadi Syakur, Wahyu Danumulyo Apr 2003

Photocatalytic Treatment Of Heavy Metal Waste Cr(Vi) Withtio2 Photocatalyst, Slamet Slamet, Riyadi Syakur, Wahyu Danumulyo

Makara Journal of Technology

Photocatalytic Treatment of Heavy Metal Waste Cr(VI) with TiO2 Photocatalyst. The photocatalytic reduction of hexavalent chromium/Cr(VI) using TiO2 and copper-doped TiO2 as photocatalysts have been studied in stirred tank and circulating photoreactors. All photocatalysts were characterized with FTIR (Fourier Transform Infra Red), BET (Brunauer-Emmett-Teller), XRD (X-Ray Diffraction) and SEM (Scanning Electron Microscope). TiO2 Merck and Degussa P-25 are the commercial photocatalysts used to compare the photocatalytic activity of all the prepared catalysts. Blank test experiments as well as the effect of dopants, EDTA (ethylenediaminetetraacetic acid) and activated carbon addition were studied. Cr(VI) reduction on various pH and initial Cr(VI) concentration …


Development And Analysis Of Geographic Information System For Electricity Network (Case Study: Surabaya Industrial Estate Rungkut In Surabaya)., Lilik Jamilatul Awalin, Bangun Muljo Sukojo Apr 2003

Development And Analysis Of Geographic Information System For Electricity Network (Case Study: Surabaya Industrial Estate Rungkut In Surabaya)., Lilik Jamilatul Awalin, Bangun Muljo Sukojo

Makara Journal of Technology

Development and Analysis of Geographic Information System for Electricity Network (Case Study: Surabaya Industrial Estate Rungkut in Surabaya). Geographic Information System (GIS) is a system of data which has spatial base. This may be cause has ability to process and analysis data quickly. The ability of GIS will be able to process the alternative in decision making. The need of electric power grows until recent time along with the existence of industrial sector expansion and land use expansion claim better service, large and balance stock of electric power. GIS is a solution for planning and managing data base system, for …


Application Of Remote Sensing And Geographic Information System Methods For Land Using Difference, Bangun Muljo Sukojo, Diah Susilowati Apr 2003

Application Of Remote Sensing And Geographic Information System Methods For Land Using Difference, Bangun Muljo Sukojo, Diah Susilowati

Makara Journal of Technology

Application of Remote Sensing and Geographic Information System Methods for Land Using Difference. Land using difference analysis has been done using remote sensing and Geographic Information System (GIS) methods. Identification of land using difference was conducted using map overlaying process of 1990s (digitized scalling 1:50.000) and 1997s land using map (interpreted from Landsat TM (Thematic Mapper) Image 1997) with UTM (Universal Transverse Mercator) coordinate. Image enhancement was done through histogram equalization with supervised classification devided into 7 classes: rice field, settlement, dry field, industry, pond, sport field and bush. Land using difference and river pollution BOD (Biological Oxygen Demand), COD …


Phase Composition Analysis Using Rietveld Methode And It's Influence To The Hardness Of Ti-Si-N Nanocomposites, Keba Moto, Lia Setiarini, Zufar Abubakar Apr 2003

Phase Composition Analysis Using Rietveld Methode And It's Influence To The Hardness Of Ti-Si-N Nanocomposites, Keba Moto, Lia Setiarini, Zufar Abubakar

Makara Journal of Technology

Phase composition analysis using rietveld methode and it’s influence to the hardness of Ti-Si-N nanocomposites. XRD data of nanocomposites Ti-Si-N have been analysed using GSAS based on Rietveld Method in order to identify phases and their composition as well as its influence on the hardness of these nanocomposites. Several new phases have been found in the sample beside the nc-TiN/a-Si3N4& a-/nc-TiSi2 that have been known widely. From the obtained crystalline phase, after the calculation of amorf Si3N4 and TiSi2 phase fraction, it is found that the optimum hardness can be reached when the fraction of a-Si3N4 phase around 8 wt.%


Influence Of Strain Rate And Temperature Of Hot Tension Testing On Mechanical Properties Of Medium Carbon Steel S48c, Dedi Priadi, Iwan Setyadi, Eddy S. Siradj Apr 2003

Influence Of Strain Rate And Temperature Of Hot Tension Testing On Mechanical Properties Of Medium Carbon Steel S48c, Dedi Priadi, Iwan Setyadi, Eddy S. Siradj

Makara Journal of Technology

Influence of Strain Rate and Temperature of Hot Tension Testing on Mechanical Properties of Medium Carbon Steel S48C. The characterization of S48C by hot tension testing was done to understanding the influence of temperature and strain rate for S48C flow stress, that close relationship with its forge ability. The hot tension testing was performed on temperatures and strain rates variation (T 850, 900, 950 0C and έ 0,01;1 s-1). The result of hot tension testing showed that increasing temperature decreases ultimate tensile strength (UTS) and flow stress of S48C. The higher decreasing of UTS is on 950 0C about 85% …


Microreactor System With Immobilized Enzyme On Polydimethylsiloxane (Pdms) Polymers, Zonghuan Lu Mar 2003

Microreactor System With Immobilized Enzyme On Polydimethylsiloxane (Pdms) Polymers, Zonghuan Lu

Doctoral Dissertations

Microsystems, specifically microreactors, open the gate to new, improved analytical techniques while offering many advantages for a large number of applications in chemical engineering, pharmacy, medicine, and biotechnology. This study explored the feasibility of fabrication of microreactors using polydimethylsiloxane (PDMS) as a support for enzyme immobilization. Urease enzyme was used for catalyzing the conversion of urea to ammonia.

PDMS (polydimethylsiloxane) is a silicone-based elastomeric polymer. Traditional micromanufacturing technology was employed for reactor mold fabrication. The mold was fabricated based on photolithography techniques, and SU-8 photoresist was used to construct reactor structure templates. The resulting silicon-wafer based reactor molds were then …


Interaction Energy Surfaces Of Small Hydrocarbon Molecules, Richard L. Rowley, Jukka-Pekka Jalkanen, Tapani A. Pakkanen, Yan Yang Mar 2003

Interaction Energy Surfaces Of Small Hydrocarbon Molecules, Richard L. Rowley, Jukka-Pekka Jalkanen, Tapani A. Pakkanen, Yan Yang

Faculty Publications

Nonbonding interactions of small alkane molecules were studied with ab initio methods. Previously reported energy data for ethane and propane dimers were supplemented with 1747 new configurations of dimers involving slightly larger hydrocarbons. The completed work provides interaction energy surfaces for all combinations of dimer pairs involving ethane, propane, isobutane, and neopentane and thus contains information of all chemical groups found in acyclic alkanes. The strongest attraction of the studied molecule pairs was encountered in isobutane C2h dimer, where an energy minimum of -1.784 kcal mol^-1 at 4.28 Angstroms separation of centermost carbon atoms was observed. The composite data set …


Natural Convection And Solid Phase Combustion, S. E. Whitney, Hendrik J. Viljoen Mar 2003

Natural Convection And Solid Phase Combustion, S. E. Whitney, Hendrik J. Viljoen

Papers in Reaction Kinetics

Self-propagating high-temperature synthesis [SHS] is a combustion process involving two or more solid reactants. The typical SHS configuration consists of a cylindrical preform of mixed powders, placed in an inert gas chamber, and ignited at one end. In past studies, interaction between the solid phase and the ambient gas phase has been limited to heat losses from the solid; the influence of natural convection on the solid phase has never been considered. In this study, computational fluid dynamics [CFD] is used, and it is shown that intense convection flow develops in the proximity of the combustion front. Gas flows adjacent …


Effective Thermal Conductivity Estimates Of Particulate Mixtures, Christiaan Richter, Hendrik J. Viljoen, N.F.J Van Rensburg Mar 2003

Effective Thermal Conductivity Estimates Of Particulate Mixtures, Christiaan Richter, Hendrik J. Viljoen, N.F.J Van Rensburg

Papers in Reaction Kinetics

Several theories have been advanced to estimate effective thermal conductivities of particulate mixtures, but most theories have focused on the dilute case. A method is proposed to estimate the effective thermal con-ductivity coefficient of mixtures of arbitrary concentration. Earlier the authors developed a theory to deter-mine the expected contact area between different species. This theory is employed to determine the Kapitza resistance of the heterogeneous mixture and forms part of an overall theory to estimate the effective thermal conductivity. Results are compared with other theoretical estimates and with experiments.


Gibbs Dividing Surface And Helium Adsorption, Sasidhar Gumma, Orhan Talu Mar 2003

Gibbs Dividing Surface And Helium Adsorption, Sasidhar Gumma, Orhan Talu

Chemical & Biomedical Engineering Faculty Publications

All adsorption data is based on the definition of Gibbs dividing surface, which is a purely mathematical transformation. Adsorption measurements in microporous solids necessitate experimental determination of the dividing surface. An international protocol does not exist on how to perform this important measurement. Commonly, helium is assumed not to adsorb and used as a probe molecule for this measurement. Each experimentalist chooses an arbitrary set of conditions, often without even disclosing them, which adds to the confusion in adsorption literature. Here, a self-consistent method for the analysis of helium data is proposed which does not assume non-adsorbing helium …


Single Fiber Model Of Particle Retention In An Acoustically Driven Porous Mesh, Michael T. Grossner, Alan E. Penrod, Joanne M. Belovich, Donald L. Feke Mar 2003

Single Fiber Model Of Particle Retention In An Acoustically Driven Porous Mesh, Michael T. Grossner, Alan E. Penrod, Joanne M. Belovich, Donald L. Feke

Chemical & Biomedical Engineering Faculty Publications

A method for the capture of small particles (tens of microns in diameter) from a continuously flowing suspension has recently been reported. This technique relies on a standing acoustic wave resonating in a rectangular chamber filled with a high-porosity mesh. Particles are retained in this chamber via a complex interaction between the acoustic field and the porous mesh. Although the mesh has a pore size two orders of magnitude larger than the particle diameter, collection efficiencies of 90% have been measured. A mathematical model has been developed to understand the experimentally observed phenomena and to be able to predict filtration …


Effective Thermal Conductivity Estimates Of Particulate Mixtures, Christiaan Richter, Hendrik J. Viljoen, N.F.J Van Rensburg Mar 2003

Effective Thermal Conductivity Estimates Of Particulate Mixtures, Christiaan Richter, Hendrik J. Viljoen, N.F.J Van Rensburg

Papers in Physical Properties

Several theories have been advanced to estimate effective thermal conductivities of particulate mixtures, but most theories have focused on the dilute case. A method is proposed to estimate the effective thermal conductivity coefficient of mixtures of arbitrary concentration. Earlier the authors developed a theory to determine the expected contact area between different species. This theory is employed to determine the Kapitza resistance of the heterogeneous mixture and forms part of an overall theory to estimate the effective thermal conductivity. Results are compared with other theoretical estimates and with experiments.


Density Of States Simulations Of Proteins, Nitin Rathore, Thomas A. Knotts Iv, Juan J. De Pablo Mar 2003

Density Of States Simulations Of Proteins, Nitin Rathore, Thomas A. Knotts Iv, Juan J. De Pablo

Faculty Publications

A modified version of a recently introduced algorithm that calculates density of states by performing a random walk in energy space has been proposed and implemented to study protein folding in a continuum. A united atom representation and the CHARMM19 [B. R. Brooks, R. E. Bruccoleri, B. D. Olafson, D. J. States, S. Swaminathan, and M. Karplus, J. Comput. Chem. 4, 187 (1983)] force field are employed for these simulations. This method permits estimation of the density of states of a protein via a random walk in the energy space, thereby allowing the system to escape from local free-energy minima …


The Study On The Synthesis And Electrochemical Property Of K2Feo4, Yong-Long Wang, Ning Zhou, Shi-Hai Ye, Xue-Ping Gao, Feng Wu, Zuo-Xiang Zhou, De-Ying Song Feb 2003

The Study On The Synthesis And Electrochemical Property Of K2Feo4, Yong-Long Wang, Ning Zhou, Shi-Hai Ye, Xue-Ping Gao, Feng Wu, Zuo-Xiang Zhou, De-Ying Song

Journal of Electrochemistry

The synthesis,characterization and electrochemical property of K2FeO4 for positive materal of lithium ion battery were studied. K2FeO4 with low purity was gained through the reaction of KCIO and Fe(NO3)3 in KOH solution and after recrystalization the purity of K2FeO4 reached 97%~98%. The methods of XRD and FTIR were used to measure the structure of K2FeO4 and its initial discharge performance was tested.


An Eqcm Study Of Water Adsorption And Oxidation On Pt Electrodes In Sulfate Acid Sulotions, Heng Lin, Sheng-Pei Chen, Jin-Mei Lin, Ai-Lan Lin, Guo-Liang Chen Feb 2003

An Eqcm Study Of Water Adsorption And Oxidation On Pt Electrodes In Sulfate Acid Sulotions, Heng Lin, Sheng-Pei Chen, Jin-Mei Lin, Ai-Lan Lin, Guo-Liang Chen

Journal of Electrochemistry

Simultaneous frequency and current responses during potential cycling of Pt electrode were measured in 0.1 mol·L-1 H2SO4 solution by using EQCM. Quantitative analysis of the mass change revealed that the increase of mass in the hydrogen and double-layer regions in a positive-going potential scan was due to water adsorption on the Pt electrode, further calculation indicated that water molecules adsorbed on Pt electrode in the double-layer regions through a low discharge quomodo .The EQCM studies provided quantitative results of surface mass variation during water adsorption and oxidation,and have thrown new light in elucidating the structure of …


Electroreduction Of Cd(Ⅱ) In Dmso And Complexation Of Cd(Ⅱ) With Coumarin Derivates, Ji-Guo Song, Hua-Can Song, Qi-Qin Yang, Yi-Wen Chen, Zun-Le Xu Feb 2003

Electroreduction Of Cd(Ⅱ) In Dmso And Complexation Of Cd(Ⅱ) With Coumarin Derivates, Ji-Guo Song, Hua-Can Song, Qi-Qin Yang, Yi-Wen Chen, Zun-Le Xu

Journal of Electrochemistry

Cadmium p-toluenesulfonate was synthesized and tested electrochemically for the first time. This salt can lose all the hydrated water easily and the dehydrated salt do not deliquesce in the air.Hence,the cadmium p-toluenesulfonate is suitable for the electrochemical studies in organic solvents.When the Cd(Ⅱ) reduced on Pt electrode in Cd(p-CH3C6H4SO3)2+TBAP+DMSO, underpotential deposition of cadmium occurred at first, and then cadmium deposited. 4-Methyl-7-hydroxylcoumarin and 3-aminocoumarin coordinate with Cd(Ⅱ) respectively, as a result the reductive potentials of Cd(Ⅱ) moved to the negative direction.


Synthesis By Complexation Processes And Characterization Of Lini0.8Co0.2O2 Cathode Materials, Jing Liu, Zhao-Yin Wen, Zhong-Hua Gu, Xiu-Jian Zhu, Zu-Xiang Lin Feb 2003

Synthesis By Complexation Processes And Characterization Of Lini0.8Co0.2O2 Cathode Materials, Jing Liu, Zhao-Yin Wen, Zhong-Hua Gu, Xiu-Jian Zhu, Zu-Xiang Lin

Journal of Electrochemistry

The layered LiNi0.8Co0.2O2 compound, which has been of great interest for lithium ion batteries, was prepared at low temperatures by calcining a complex precursor at different temperatures. The physical properties of the synthesized cathode materials were discussed in the light of structural (XRD). The charge and discharge cycling of the cells containing the synthesized oxide as the positive electrode in conjunction with lithium metals and employing a non-aqueous electrolyte showed that LiNi0.8Co0.2O2 treated at 900 ℃ exhibited excellent performances. The first discharge capacity of LLiNi0.8Co0.2O2 …


Fuel Characteristics Of Processed, High-Fiber Sugarcane, Scott Q. Turn, Charles M. Kinoshita, Lee A. Jakeway, Bryan M. Jenkins, Larry Lin Baxter 8507091, Ben C. Wu, Linda G. Blevins Feb 2003

Fuel Characteristics Of Processed, High-Fiber Sugarcane, Scott Q. Turn, Charles M. Kinoshita, Lee A. Jakeway, Bryan M. Jenkins, Larry Lin Baxter 8507091, Ben C. Wu, Linda G. Blevins

Faculty Publications

A study of treatment methods to improve the fuel characteristics of sugarcane variety B52298 was conducted. Two parent materials, whole cane (WC) and stripped cane (SC), were included in the study. The whole cane material was subjected to three treatments: (1) no treatment, WC-U; (2) a single milling, WC-M; and (3) an initial milling followed by leaching and a secondary milling, WC-MLM. Treatments (1) through (3) are in order of increasing severity. The stripped cane material was subjected to treatment (3) and designated as SC-MLM. Regardless of parent material, milling produced moisture contents of ∼50% wet basis and fiber bulk …


Relaxation Of A Rubbed Polystyrene Surface, Alexander D. Schwab, Ali Dhinojwala Feb 2003

Relaxation Of A Rubbed Polystyrene Surface, Alexander D. Schwab, Ali Dhinojwala

College of Polymer Science and Polymer Engineering

The relaxation dynamics of a rubbed polystyrene (PS) surface have been characterized using infrared-visible sum frequency generation spectroscopy (SFG). The SFG results were compared with previous relaxation of retardation measurements, and the results show that the rubbed PS surface has the same T(g) as the bulk where T(g) is defined as tau(T(g))=5 s, however, the surface has a lower activation energy (DeltaE) and a larger stretching exponent (beta(KWW)) than bulk PS. This indicates that the surface region relaxes more quickly than the bulk. The thickness of this region of lower DeltaE and larger beta(KWW) is estimated to be roughly 12 …


Transgenic Non-Human Mammals Expressing Human Coagulation Factor Viii And Von Willebrand Factor, Henryk Lubon, William N. Drohan, William H. Velander Feb 2003

Transgenic Non-Human Mammals Expressing Human Coagulation Factor Viii And Von Willebrand Factor, Henryk Lubon, William N. Drohan, William H. Velander

Papers in Biotechnology

A non-human transgenic mammalian animal, as described above, contains an exogenous double stranded DNA sequence stably integrated into the genome of the animal, which comprises cis-acting regulatory units operably linked to a DNA sequence encoding human Factor VIII protein and a signal peptide, where the cis-acting regulatory units are active in mammary gland cells and the signal peptide is active in directing newly expressed Factor VIII into the milk of the animal. The promoter may be a milk protein promoter such as for whey acidic protein, casein, lactalbumin, or beta-lactoglobulin promoter. The transgenic mammals are preferably farm animals, for example, …


Comprehensive Model Of Alkali-Salt Deposition In Recovery Boilers, Richard A. Wessel, Larry Lin Baxter 8507091 Feb 2003

Comprehensive Model Of Alkali-Salt Deposition In Recovery Boilers, Richard A. Wessel, Larry Lin Baxter 8507091

Faculty Publications

Algorithms for alkali-salt deposition have been implemented into a comprehensive model for recovery boilers. The model includes (a) mechanisms for particle formation and chemistry, (b) particle deposition and adhesion, and (c) deposit thermal properties. These algorithms are fully coupled with models for turbulent flow, black liquor combustion, and heat transfer in the boiler. Model predictions for particle deposition in the convection pass are presented for a Babcock & Wilcox recovery boiler. This work is part of an ongoing project sponsored by the U.S. Department of Energy to demonstrate an improved ability to anticipate ash behavior with changes in fuel composition, …


A Reactive Melt Modification Of Polyethylene Terephthalate, Rahul Ramesh Dhavalikar Jan 2003

A Reactive Melt Modification Of Polyethylene Terephthalate, Rahul Ramesh Dhavalikar

Dissertations

This work investigates the structural and chemorheological modification of polyethylene terephthalate in the melt phase with low molecular weight multifunctional glycidyl compounds as reactive additives. Polyethylene terephthalate undergoes chain extension and/or branching reactions with the additives that result in modified rheological properties suitable for certain polymer processing operations such as extrusion blow molding or extrusion foaming to low densities.

Among five different low MW difunctional and trifunctional epoxy compounds, triglycidyl isocyanurate is shown to be an efficient reactive melt modifier for commercially available polyethylene terephthalate polymers. Its stability at the polyethylene terephthalate melt temperatures is confirmed offline through thermogravimetric and …


Study Of Vapor/Gas Permeation Using Thin Immobilized Liquid Membrane, Gordana Obuskovic Jan 2003

Study Of Vapor/Gas Permeation Using Thin Immobilized Liquid Membrane, Gordana Obuskovic

Dissertations

To improve liquid membrane selectivity and stability for removal of vapor and gases from a gas stream, a thin immobilized liquid membrane (ILM) has been studied. Low vapor pressure liquid solvent/solutions were immobilized in part of the micropores of a hydrophilic, hydrophobic or ceramic hollow fiber substrate. To prepare such thin ILMs, three approaches were used: evaporation of the a volatile solvent; acrylic acid-grafted hollow fibers providing a thin hydrophilic layer; pressurization technique.

For removal of volatile organic compound (VOC), a thin ILM of silicone oil incorporated in the micropores of a hydrophobic hollow fiber with a silicone rubber coating …


Liquid-Liquid Mixing In Stirred Tanks With Varying Liquid Depths, Sunil Mehta Jan 2003

Liquid-Liquid Mixing In Stirred Tanks With Varying Liquid Depths, Sunil Mehta

Theses

Considerable attention has been devoted in the past to the determination of the minimum agitation speed, Ncd, required for the complete dispersion of two immiscible liquids in mechanically stirred tanks. When this situation is achieved the dispersed phase is no longer present as a distinct layer, such as a light oil phase above an aqueous solution, but becomes completely dispersed, in the form of droplets, throughout the continuous phase. The achievement of the dispersed state is of significant importance in many industrial operations. Nevertheless, the effect on Ncd of a number of operating variables remains poorly understood. …