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Articles 1021 - 1050 of 1407

Full-Text Articles in Biochemical and Biomolecular Engineering

Effect Of Shear On Performance And Microbial Ecology Of Continuously Stirred Anaerobic Digesters Treating Animal Manure, Rebecca A. Hoffmann, Marcelo L. Garcia, Mehul Veskivar, Khursheed Karim, Muthanna H. Al-Dahhan, Largus T. Angenent May 2008

Effect Of Shear On Performance And Microbial Ecology Of Continuously Stirred Anaerobic Digesters Treating Animal Manure, Rebecca A. Hoffmann, Marcelo L. Garcia, Mehul Veskivar, Khursheed Karim, Muthanna H. Al-Dahhan, Largus T. Angenent

Chemical and Biochemical Engineering Faculty Research & Creative Works

We Determined the Effect of Different Mixing Intensities on the Performance, Methanogenic Population Dynamics, and Juxtaposition of Syntrophic Microbes in Anaerobic Digesters Treating Cow Manure from a Dairy Farm. Computer Automated Radioactive Particle Tracking in Conjunction with Computational Fluid Dynamics Was Performed to Quantify the Shear Levels Locally. Four Continuously Stirred Anaerobic Digesters Were Operated at Different Mixing Intensities of 1,500, 500, 250, and 50 Revolutions Per Min (RPM) over a 260-Day Period at a Temperature of 34 ± 1°C. Animal Manure at a Volatile Solids (VS) Concentration of 50 G/L Was Fed into the Digesters Daily at Five Different …

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The Processing, Mechanical Properties And Bioactivity Of Strontium Based Glass Polyalkenoate Cements, Anthony Wren, Daniel Boyd, Mark R. Towler Apr 2008

The Processing, Mechanical Properties And Bioactivity Of Strontium Based Glass Polyalkenoate Cements, Anthony Wren, Daniel Boyd, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The suitability of zinc-based glass polyalkenoate cements (GPCs) for use in orthopaedics can be improved by the substitution of strontium into the glass phase which should impart improved radiopacity and bone forming properties to the cements without retarding strength. The purpose of this research was to produce novel GPCs based on calcium-strontium-zinc-silicate glasses and to evaluate their mechanical properties and biocompatibility with the ultimate objective of developing a new range of cements for skeletal applications. Three glass compositions, based on incremental substitutions of strontium for calcium, were synthesized; BT100 (0.16CaO, 0.36ZnO, 0.48SiO2), BT101 (0.04SrO, 0.12CaO, 0.36ZnO, 0.48SiO2 …

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Off And Running, James D. Sterling Apr 2008

Off And Running, James D. Sterling

Business and Information Technology Faculty Research & Creative Works

No abstract provided.

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Comparison Of An Experimental Bone Cement With Surgical Simplex® P, Spineplex® And Cortoss®, D. Boyd, Mark R. Towler, A. Wren, O. M. Clarkin Apr 2008

Comparison Of An Experimental Bone Cement With Surgical Simplex® P, Spineplex® And Cortoss®, D. Boyd, Mark R. Towler, A. Wren, O. M. Clarkin

Chemical and Biochemical Engineering Faculty Research & Creative Works

Conventional polymethylmethacrylate (PMMA) cements and more recently Bisphenol-a-glycidyl dimethacrylate (BIS-GMA) composite cements are employed in procedures such as vertebroplasty. Unfortunately, such materials have inherent drawbacks including, a high curing exotherm, the incorporation of toxic components in their formulations, and critically, exhibit a modulus mismatch between cement and bone. The literature suggests that aluminum free, zinc-based glass polyalkenoate cements (Zn-GPC) may be suitable alternative materials for consideration in such applications as vertebroplasty. This paper examines one formulation of Zn-GPC and compares its strengths, modulus, and biocompatibility with three commercially available bone cements, Spineplex®, Simplex® P and Cortoss®. The setting times indicate …

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Electrochemical Durability Of Carbon Nanotubes At 80 °C, Liang Li, Yangchuan Xing Mar 2008

Electrochemical Durability Of Carbon Nanotubes At 80 °C, Liang Li, Yangchuan Xing

Chemical and Biochemical Engineering Faculty Research & Creative Works

Carbon nanotubes (CNTs) have been studied as an alternative catalyst support in polymer electrolyte membrane (PEM) fuel cells. Recent studies showed that CNTs appear to be more resistant to electrochemical corrosion than carbon black (CB). in a previous study, we have demonstrated the room temperature durability of multiwalled CNTs in both non-catalyzed and catalyzed electrochemical oxidations. This paper is to report results conducted at 80 °C-an operational temperature of PEM fuel cells. It was found that multiwalled CNTs are still more resistant than CB at the elevated temperature. However, the electrochemical oxidation rate is more rapid than that at the …

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Macro-Mixing In A Draft-Tube Airlift Bioreactor, Hu Ping Luo, Muthanna H. Al-Dahhan Mar 2008

Macro-Mixing In A Draft-Tube Airlift Bioreactor, Hu Ping Luo, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Airlift Reactors Are Pneumatically Agitated Reactors that Have Been Widely Used in Industries, Particularly in Bioprocesses. Extensive Studies About the Flow Dynamics in Airlift Column Reactors Exist; However, Most of These Studies Have Focused on Global Hydrodynamic Parameters using Conventional Techniques. the Local Flow Characteristics, such as the Macro-Mixing and the Turbulence Intensity, Are Crucial for Reliable Design and Scale-Up, and They Remain Unclear. This Work Focuses on Studying the Macro-Mixing in a Draft-Tube Airlift Bioreactor Utilizing an Advanced Flow Dynamic Measurement Technique, Computer Automated Radioactive Particle Tracking (CARPT). True Residence Time Distribution Analyses for the overall Column as Well …

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The Role Of Sr²⁺ On The Structure And Reactivity Of Sro-Cao-Zno-Sio2 Ionomer Glasses, Daniel Boyd, Mark R. Towler, Sally Watts, Robert G. Hill, Anthony W. Wren, Owen M. Clarkin Feb 2008

The Role Of Sr²⁺ On The Structure And Reactivity Of Sro-Cao-Zno-Sio2 Ionomer Glasses, Daniel Boyd, Mark R. Towler, Sally Watts, Robert G. Hill, Anthony W. Wren, Owen M. Clarkin

Chemical and Biochemical Engineering Faculty Research & Creative Works

The suitability of Glass Polyalkenoate Cements (GPCs) for use in orthopaedics is retarded by the presence in the glass phase of aluminum, a neurotoxin. Unfortunately, the aluminum ion plays an integral role in the setting process of GPCs and its absence is likely to hinder cement formation. However, the authors have previously shown that aluminum free GPCs may be formulated based on calcium zinc silicate glasses and these novel materials exhibit significant potential as hard tissue biomaterials. To further improve their potential and given that Strontium (Sr) based drugs have had success in the treatment of osteoporosis, the authors have …

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Bubble Velocity, Size, And Interfacial Area Measurements In A Bubble Column By Four-Point Optical Probe, Junli Xue, Muthanna H. Al-Dahhan, M. P. Dudukovic, R. F. Mudde Feb 2008

Bubble Velocity, Size, And Interfacial Area Measurements In A Bubble Column By Four-Point Optical Probe, Junli Xue, Muthanna H. Al-Dahhan, M. P. Dudukovic, R. F. Mudde

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Four-Point Optical Probe is Applied in a Bubble Column with an Air-Water System to Investigate the Bubble Properties (Local Gas Holdup, Velocity, Chord Length, Specific Interfacial Area, and Frequency) over a Range of Gas Superficial Velocities. Both Bubbles Moving Upward and Downward Are Recorded and Measured as Opposed to Only Upward Bubbles Measured and Reported in Other Studies Involving Probes. the Probe Worked Efficiently in Both Bubbly Flow and Highly Churn-Turbulent Flow at Very High Superficial Gas Velocities. Bubble Properties at the Conditions of Churn-Turbulent Flow Are Obtained and Investigated for the First Time. the Changes in the Bubble …

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Modeling Of Trickle-Bed Reactors With Exothermic Reactions Using Cell Network Approach, Jing Guo, Yi Jiang, Muthanna H. Al-Dahhan Feb 2008

Modeling Of Trickle-Bed Reactors With Exothermic Reactions Using Cell Network Approach, Jing Guo, Yi Jiang, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

One-Dimensional (1D) and Two-Dimensional (2D) Cell Network Models Were Developed to Simulate the Steady-State Behavior of Trickle-Bed Reactors Employed for the Highly Exothermic Hydrotreating of Benzene. the Multiphase Mass Transfer-Reaction Model and Novel Solution Method Are Discussed in This Report. the 1D Model Was Shown to Satisfactorily Simulate the Axial Temperature Field Observed Experimentally for Multiphase Flow with Exothermic Reactions. the 2D Reactor Modeling Provided Valuable Information About Local Hot Spot Behavior within the Multiphase Reactor, Identifying Situations in Which Hot Spots May Form. the Model Took into Consideration the Heterogeneous Nature of Liquid Distribution, Including Radial Liquid Maldistribution and …

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Tem Analysis Of Apatite Surface Layers Observed On Zinc Based Glass Polyalkenoate Cements, D. Boyd, Mark R. Towler, A. W. Wren, O. M. Clarkin, D. A. Tanner Feb 2008

Tem Analysis Of Apatite Surface Layers Observed On Zinc Based Glass Polyalkenoate Cements, D. Boyd, Mark R. Towler, A. W. Wren, O. M. Clarkin, D. A. Tanner

Chemical and Biochemical Engineering Faculty Research & Creative Works

The amorphous nature and composition of the surface apatite layers observed on glass polyalkenoate cements based on zinc silicate glasses (Zn-GPCs) after immersion in simulated body fluid (SBF) have been analyzed by the transmission electron microscopy (TEM). TEM was conducted using a JEOL JEM-2011 electron microscope operated at an accelerating voltage of 200 kV. The composition elements of the surface layer indicated the presence of calcium, phosphorous, zinc, and strontium within the amorphous structure. This composition, in particular the inclusion of Zn in the structure, indicates the lack of crystallinity associated with the formation of the apatite layers observed on …

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Digestion Of Sand-Laden Manure Slurry In An Upflow Anaerobic Solids Removal (Uasr) Digester, Khursheed Karim, Rebecca Hoffmann, M. (Muthanna) H. Al-Dahhan Feb 2008

Digestion Of Sand-Laden Manure Slurry In An Upflow Anaerobic Solids Removal (Uasr) Digester, Khursheed Karim, Rebecca Hoffmann, M. (Muthanna) H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Studies on the Performance of a Laboratory Scale Up flow Anaerobic Solids Removal (UASR) Digester Were Carried Out using Sand-Laden Cow Manure Slurries Having Total Solids (TS) Concentration as 50 and 100 G/l. Hydraulic Retention Time (HRT) Was Maintained as 32.4 Days, Which Resulted in the Volatile Solids (VS) Loading Rates of 1 and 1.64 G/l D. the UASR System Was Designed to Remove Sand from the Manure Slurry, While Anaerobically Digesting Biodegradable Solids Inside a Single Reactor. to Enhance the Contact of Microorganisms and Substrate, the Liquor from the Top of the Digester Was Recirculated through the Bed of …

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A Comparison Of Alternating Minimization And Expectation Maximization Algorithms For Single Source Gamma Ray Tomography, R. Varma, S. Bhusarapu, J. A. O'Sullivan, M. (Muthanna) H. Al-Dahhan Jan 2008

A Comparison Of Alternating Minimization And Expectation Maximization Algorithms For Single Source Gamma Ray Tomography, R. Varma, S. Bhusarapu, J. A. O'Sullivan, M. (Muthanna) H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Lange and Carson (1984 J. Comput. Assist. Tomogr. 8 306-16) Defined Image Reconstruction for Transmission Tomography as a Maximum Likelihood Estimation Problem and Derived an Expectation Maximization (EM) Algorithm to Obtain the Maximum Likelihood Image Estimate. However, in the Maximization Step or M-Step of the EM Algorithm, an Approximation is Made in the Solution Which Can Affect the Image Quality, particularly in the Case of Domains with High Attenuating Material. O'Sullivan and Benac (2007 IEEE Trans. Med. Imaging 26 283-97) Reformulated the Maximum Likelihood Problem as a Double Minimization of an I-Divergence to Obtain a Family of Image Reconstruction Algorithms, …

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Effect Of Hydrodynamic Multiplicity On Trickle Bed Reactor Performance, Werner Van Der Merwe, Willie Nicol, Muthanna H. Al-Dahhan Jan 2008

Effect Of Hydrodynamic Multiplicity On Trickle Bed Reactor Performance, Werner Van Der Merwe, Willie Nicol, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Multiple Hydrodynamic States in Trickle Bed Reactors Have Been the Subject of Numerous Hydrodynamic Investigations. the Extent of Variation in the Hydrodynamic Parameters (Like Holdup and Pressure Drop) is Large and This Variation Can Be Expected to Have a Significant Impact on the Conversion in a Reaction System. This Study Presents Reaction Data for Α-Methyl Styrene Hydrogenation in a Trickle Bed Reactor over a Range of Conditions that Include Gas and Liquid Limitations. It is Seen that Liquid Flow Rate Variation Induced Hysteresis Has a Large Impact on the Conversion. for Gas-Limited Reactions, the Upper Branch of the Pressure Drop …

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Effect Of Sparger Design On Hydrodynamics Of A Gas Recirculation Anaerobic Bioreactor, Rajneesh Varma, Muthanna H. Al-Dahhan Dec 2007

Effect Of Sparger Design On Hydrodynamics Of A Gas Recirculation Anaerobic Bioreactor, Rajneesh Varma, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Effects of Sparger Design and Gas Flow Rate On, Gas Holdup Distribution and Liquid (Slurry) Recirculation Velocity Have Been Studied in a Surrogate Anaerobic Bioreactor Used for Treating Bovine Waste with a Conical Bottom Mixed by Gas Recirculation. a Single Orifice Sparger (SOS) and a Multi-Orifice Ring Sparger (MORS) with the Same Orifice Open Area and Gas Flow Rates (Hence the Same Process Power Input) Are Compared in This Study. the Advanced Non-Invasive Techniques of Computer Automated Tomography (CT) and Computer Automated Radioactive Particle Tracking (CARPT) Were Employed to Determine Gas Holdup, Liquid Recirculation Velocity, and the Poorly Mixed …

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Numerical Simulation Of Gas-Solid Dynamics In A Circulating Fluidized-Bed Riser With Geldart Group B Particles, S. Vaishali, Shantanu Roy, Satish Bhusarapu, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic Dec 2007

Numerical Simulation Of Gas-Solid Dynamics In A Circulating Fluidized-Bed Riser With Geldart Group B Particles, S. Vaishali, Shantanu Roy, Satish Bhusarapu, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

Circulating Fluidized-Bed (CFB) Risers with Geldart Group B Particles Have Found Significant Application in Combustion Reactions. the Present Work Attempts to Study the Solids Flow Dynamics in a CFB Riser that is Operated with Group B Particles, using Computational Fluid Dynamics (CFD) Techniques. the Key Feature in the Present Study is that the Various Closure Schemes in the CFD Model Have Been Evaluated Against Data from Non-Invasive Experimental Techniques: Computer Automated Radioactive Particle Tracking (CARPT) for Solids Velocity Field and Computed Tomography (CT) for Solids Holdup. Since Solids Flow in a Riser is Multiscale in Character, in Addition to the …

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Moment Analysis Of Near-Equilibrium Binding Interactions During Electrophoresis, Yousef Daneshbod, James D. Sterling, Ali Nadim Nov 2007

Moment Analysis Of Near-Equilibrium Binding Interactions During Electrophoresis, Yousef Daneshbod, James D. Sterling, Ali Nadim

Business and Information Technology Faculty Research & Creative Works

The electrophoretic transport of three chemically reacting species, two of which can bind reversibly to form the third, is analyzed mathematically. The species are assumed to move horizontally through a long channel with different electrophoretic mobilities and diffusion coefficients. By considering small perturbations of the system about equilibrium or when one of the two binding species is much more abundant than the other, the governing advection-reaction- diffusion equations can be linearized and studied via the method of moments. The result is a set of coupled ordinary differential equations for the moments that can be solved analytically. Analysis of the long-time …

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Phase Transformations Of Calcium Phosphates Formed In Wet Field Environments, O. M. Clarkin, Mark R. Towler, G. M. Insley, M. E. Murphy Oct 2007

Phase Transformations Of Calcium Phosphates Formed In Wet Field Environments, O. M. Clarkin, Mark R. Towler, G. M. Insley, M. E. Murphy

Chemical and Biochemical Engineering Faculty Research & Creative Works

The crystal phase and morphology of calcium phosphate salts precipitated in a wet field environment at temperatures between 30 and 70 °C and pHs between 3 and 8 were examined. Dicalcium Phosphate Dihydrate (DCPD) was the most prevalent phase precipitated. Using accelerated ageing study techniques, precipitates studied were aged, under dry conditions at 50 °C for 8 and 16 days, before being re-examined using XRD, FTIR and SEM techniques. DCPD was found to be most stable when precipitated at 40 °C and 5 pH. Considerably more phase transformation to Octacalcium Phosphate (OCP), Amorphous Calcium Phosphate (ACP) and Hydroxyapatite (HA) was …

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Prediction Of The Kolmogorov Entropy Derived From Computed Tomography Data In A Bubble Column Operated Under The Transition Regime And Ambient Pressure, Stoyan Nedeltchev, Ashfaq Shaikh, Muthanna H. Al-Dahhan Oct 2007

Prediction Of The Kolmogorov Entropy Derived From Computed Tomography Data In A Bubble Column Operated Under The Transition Regime And Ambient Pressure, Stoyan Nedeltchev, Ashfaq Shaikh, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Kolmogorov Entropy (KE) Algorithm Was Successfully Applied to Single Source Γ-Ray Computed Tomography (CT) Data Measured by Three Scintillation Detectors in a 0.162 M-ID Bubble Column Equipped with a Perforated Plate Distributor (163 Holes X ∅ 1.32. 10-3 M). the Aerated Liquid Height Was Set at 1.8 M. Dried Air Was Used as a Gas Phase, While Therminol LT (PL = 886 Kg M-3, ΜL = 0.88.10-3 Pa S, Σ = 17.10-3 N M-1) Was Used as a Liquid Phase. at Ambient Pressure, the Superficial Gas Velocity, ΜG, Was Increased …

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Mesophilic Digestion Kinetics Of Manure Slurry, Khursheed Karim, K. Thomas Klasson, Sadie R. Drescher, Whitney Ridenour, Abhijeet P. Borole, Muthanna H. Al-Dahhan Sep 2007

Mesophilic Digestion Kinetics Of Manure Slurry, Khursheed Karim, K. Thomas Klasson, Sadie R. Drescher, Whitney Ridenour, Abhijeet P. Borole, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Anaerobic Digestion Kinetics Study of Cow Manure Was Performed at 35°C in Bench-Scale Gas-Lift Digesters (3.78 L Working Volume) at Eight Different Volatile Solids (VS) Loading Rates in the Range of 1.11-5.87 G L-1 Day-1. the Digesters Produced Methane at the Rates of 0.44-1.18 L L-1 Day-1, and the Methane Content of the Biogas Was Found to Increase with Longer Hydraulic Retention Time (HRT). based on the Experimental Observations, the Ultimate Methane Yield and the Specific Methane Productivity Were Estimated to Be 0.42 L CH4 (G vs. Loaded)-1 and 0.45 L CH …

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Influence Of Two Changes In The Composition Of An Acrylic Bone Cement On Its Handling, Thermal, Physical, And Mechanical Properties, G. Lewis, J. Xu, S. Madigan, Mark R. Towler Aug 2007

Influence Of Two Changes In The Composition Of An Acrylic Bone Cement On Its Handling, Thermal, Physical, And Mechanical Properties, G. Lewis, J. Xu, S. Madigan, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

This study is a contribution to the growing body of work on the influence of changes in the composition of an acrylic bone cement on various properties of the curing and cured material. The focus is on one commercially-available acrylic bone cement brand, Surgical Simplex®P, and three variants of it and a series of properties, namely, setting time, maximum exotherm temperature, activation energy and frequency factor for the polymerization reaction, diffusion coefficient for the uptake of phosphate buffered saline, at 37°C, ultimate compressive strength (UCS), plane-strain fracture toughness, fatigue life (under fully-reversed tension-compression stress), hardness (H) and elastic modulus (both …

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A Chemical Engineering Laboratory Over Distributed Control And Measurement Systems, Jing Guo, David Kettler, Muthanna H. Al-Dahhan Aug 2007

A Chemical Engineering Laboratory Over Distributed Control And Measurement Systems, Jing Guo, David Kettler, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Remote Control of Lab Apparatus Via the Internet Allows Flexible Scheduling of Experiments and Exercises. This Paper Presents a Novel Application of Computers and Internet Technology in Chemical Engineering Education that Highlights Interactive Learning for an Undergraduate Course in Online Measurement and Control. the Proposed Client-Server Architecture Can Be Adapted to Drive Different Kinds of Devices and Can Be Easily Expanded. the Developed Online Laboratory Has Been Tested by Many Students using Different Connections and Operating Conditions. This Internet-Based Solution Can Improve Undergraduate Engineering Education in a Conventional Unit Operation Laboratory. as an Example, the Application of Remote Experiments to …

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Anwendung Von Interferenz- Und Ir-Mikroskopie Zur Charakterisierung Und Untersuchung Des Stofftransportes In Nanoporösen Materialien, Lars Heinke, Christian Chmelik, Pavel Kortunov, Sergey Vasenkov, Douglas M. Ruthven, Dhananjai B. Shah, Jörg Kärger Aug 2007

Anwendung Von Interferenz- Und Ir-Mikroskopie Zur Charakterisierung Und Untersuchung Des Stofftransportes In Nanoporösen Materialien, Lars Heinke, Christian Chmelik, Pavel Kortunov, Sergey Vasenkov, Douglas M. Ruthven, Dhananjai B. Shah, Jörg Kärger

Chemical & Biomedical Engineering Faculty Publications

Die Anwendung der Interferenz-Mikroskopie bedeutet einen entscheidenden Durchbruch in der Untersuchung des Stofftransports von Gastmolekülen in nanoporösen Wirtsmaterialien. Diese Technik ermöglicht die Beobachtung der zeitaufgelösten intrakristallinen Konzentrationsprofile, die durch eine Änderung des umgebenden Gasdruckes entstehen. Dieser Ansatz wurde zur Untersuchung von Adsorptions- und Desorptionsprozessen in verschiedenen Zeolithsystemen verwendet. Die Vorteile dieser Technik, vor allem wenn sie mit Infrarotabsorptionsmessungen kombiniert wird, werden an Hand der experimentellen Resultate des Methanol-in-Ferrierit-Systems illustriert.

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Influence Of Acid Washing On The Surface Morphology Of Ionomer Glasses And Handling Properties Of Glass Ionomer Cements, C. M. Crowley, J. Doyle, Mark R. Towler, N. Rushe, S. Hampshire Aug 2007

Influence Of Acid Washing On The Surface Morphology Of Ionomer Glasses And Handling Properties Of Glass Ionomer Cements, C. M. Crowley, J. Doyle, Mark R. Towler, N. Rushe, S. Hampshire

Chemical and Biochemical Engineering Faculty Research & Creative Works

Acid washing is known to influence the handling properties of ionomer glasses used in glass ionomer cements due to the production of an ion depleted zone on the surface of the glass particles. The influence of acid washing on the particle size distribution and surface area of four glasses was examined by scanning electron microscopy (SEM), particle size analysis (PSA) and accelerated surface area porosimetry (ASAP) and the working and setting times of cements, produced from the glasses, correlated to changes in surface morphology. A linear relationship was found between the specific surface area of acid-washed SiO2-Al2 …

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Software Engineering: A Fundamental Approach To Automate And Interface Medical Electronic Systems With Computers In Healthcare Systems, Hashim Twaakyondo Jun 2007

Software Engineering: A Fundamental Approach To Automate And Interface Medical Electronic Systems With Computers In Healthcare Systems, Hashim Twaakyondo

Tanzania Journal of Engineering and Technology (TJET)

The cost for application software and propriatry standards (i.e. data structure and formats) required for storing clinical datasets from electronic device cause the use of time-consuming paper-based documentation and/or the transfer of electronic lab records manually to the PC database systems in Mother-Offspring Malaria Study (MOMS) Laboratory Unit located in Morogoro Regional Hospital, Tanzania. We have explored the ability to extract laboratory results from Haematology analyzer machine for easy management, access and storage. The methodology and tools used during the study includes; site survey and hands-on practice for requirement engineering, visual basic 6.0 for interface design and Microsoft Access for …

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Oaming Characteristics Of The Food-Industry Biological Wastewater Treatment Plant, Samwel V. Manyele Jun 2007

Oaming Characteristics Of The Food-Industry Biological Wastewater Treatment Plant, Samwel V. Manyele

Tanzania Journal of Engineering and Technology (TJET)

Intensive foaming observed during aeration of the aerobic food industry wastewater treatment plant is presented. This study was conducted to establish the foaming characteristics using a pilot three-phase fluidized bed bioreactor (TPFBB). A fluidization column (0.2 m i.d. and 6 m high) was used. The TPFBB was loaded with variable masses of novel biomass support particles (BSP). Wastewater samples collected from a plant processing both vegetable oil (VOPWW) and soap (SPWW) were immediately introduced in the TPFBB for aeration. The characteristics studied include: variation of foam volume with time, foam multiplicity, foaming and foam collapse rates. The SPWW produced excessive …

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Using A Fiber-Optic Probe For The Measurement Of Volumetric Expansion Of Liquids, Sean G. Mueller, Jay R. Werber, Muthanna H. Al-Dahhan, Milorad P. Dudukovic Jun 2007

Using A Fiber-Optic Probe For The Measurement Of Volumetric Expansion Of Liquids, Sean G. Mueller, Jay R. Werber, Muthanna H. Al-Dahhan, Milorad P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

A Fiber-Optic Probe is Developed for the Fast, In-Situ Measurement of Volumetric Expansion of Multiphase and Multicomponent Systems. an Experiment with the Binary Mixtures of CO2-Toluene and CO2-Ethanol Was Conducted to Demonstrate the Usefulness of the Fiber-Optic Probe in Accurately Tracking the Isothermal Volumetric Expansion as a Function of Pressure. in the 1-L Autoclave that Has Been Used, the Probe Was Shown to Detect the Liquid Level Height within a Precision of 0.35% of the Total Height of the Vessel. the Results for the Volumetric Expansion of Toluene and Ethanol with CO2 Correlate Well with …

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Measuring Gas-Liquid Distribution In A Pilot Scale Monolith Reactor Via An Industrial Tomography Scanner (Its), M. (Muthanna) H. Al-Dahhan, A. Kemoun, A. R. Cartolano, S. Roy, R. Dobson, J. Williams Jun 2007

Measuring Gas-Liquid Distribution In A Pilot Scale Monolith Reactor Via An Industrial Tomography Scanner (Its), M. (Muthanna) H. Al-Dahhan, A. Kemoun, A. R. Cartolano, S. Roy, R. Dobson, J. Williams

Chemical and Biochemical Engineering Faculty Research & Creative Works

An Industrial Tomography Scanner (ITS) Was Designed and Developed to Study and Quantify the Phase Distribution in a Two-Phase Flow Pilot Scale Monolith Reactor that Was 24 In. (0.60 M) in Diameter and 192 In. (4.9 M) in Height. the Monolith Reactor Was Operated Co-Current Up-Flow in the Taylor Flow Regime with Water as the Liquid Phase and Air as the Gas Phase. the Cross-Sectional Holdup Distributions Were Measured at Three Axial Elevations. the Operating Conditions Were Selected to Bracket Commercial Operating Conditions for Fixed Bed Monolithic Reactor Systems. the Results Show that its Can Capture the Flow Features in …

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Preliminary Work On The Development Of A Novel Detection Method For Osteoporosis, P. Moran, Mark R. Towler, S. Chowdhury, J. Saunders, M. J. German, N. S. Lawson, H. M. Pollock, I. Pillay, D. Lyons Jun 2007

Preliminary Work On The Development Of A Novel Detection Method For Osteoporosis, P. Moran, Mark R. Towler, S. Chowdhury, J. Saunders, M. J. German, N. S. Lawson, H. M. Pollock, I. Pillay, D. Lyons

Chemical and Biochemical Engineering Faculty Research & Creative Works

Osteoporosis affects both the organic and mineral phases of bone resulting in a decrease in resistance to fracture. Dual x-ray absorptiometry (DEXA) scans are used for diagnosing osteoporosis, which is conventionally characterized by a decrease in mineral density. Unfortunately, some patients who suffer osteoporotic fractures have normal bone density, because both the organic and the mineral phase are affected. However, there are currently no methods of evaluating the health of the organic phase. Patients undergoing treatment for osteoporosis have reported hardening of their fingernails. As the properties of nail and bone may be linked in a comparable, measurable way, this …

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Pt-Ru Nanoparticles Supported On Carbon Nanotubes As Methanol Fuel Cell Catalysts, Liang Li, Yangchuan Xing May 2007

Pt-Ru Nanoparticles Supported On Carbon Nanotubes As Methanol Fuel Cell Catalysts, Liang Li, Yangchuan Xing

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bimetallic Pt - Ru alloy catalysts have been demonstrated to be more active than pure Pt catalysts in the electrooxidation of methanol. We report here a study on Pt - Ru nanoparticle catalysts supported on sonochemically functionalized carbon nanotubes. the catalysts were prepared by directly reducing the corresponding salts, K2PtCl4 and K 2RuCl5, in an ethylene glycol aqueous solution containing dispersed carbon nanotubes. Three catalysts of different Pt to Ru atomic ratios, namely, Pt53Ru47, Pt69Ru31, and Pt77Ru23, were prepared for investigation of the compositional effects, It was shown that highly dispersed bimetallic Pt - Ru alloy nanoparticles with no agglomeration …

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Raman Spectroscopy Of The Human Nail: A Potential Tool For Evaluating Bone Health?, Mark R. Towler, A. Wren, N. Rushe, J. Saunders, N. M. Cummins, P. M. Jakeman May 2007

Raman Spectroscopy Of The Human Nail: A Potential Tool For Evaluating Bone Health?, Mark R. Towler, A. Wren, N. Rushe, J. Saunders, N. M. Cummins, P. M. Jakeman

Chemical and Biochemical Engineering Faculty Research & Creative Works

Dual X-ray absorptiometry (DEXA) is the current gold standard for the diagnosis of osteoporosis. However, patients can suffer osteoporotic fractures despite normal bone mineral density, partly because of unmeasured influences of both the protein and mineral phases of bone that are affected in osteoporosis. There is currently no clinically applicable method of evaluating the health of the protein phase. The proteins in human nail (keratin) and bone (collagen) require sulphation and disulphide bond (S-S) formation for structural integrity and disorders of either sulphur metabolism or cystathione beta-synthase can lead to structural abnormalities in these tissues. Raman protein spectra provide a …

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