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Articles 10711 - 10740 of 14131

Full-Text Articles in Engineering

A Simple Sol-Gel Processing For The Development Of High-Temperature Stable Photoactive Anatase Titania, Suresh Pillai, Declan Mccormack, John Colreavy Jan 2007

A Simple Sol-Gel Processing For The Development Of High-Temperature Stable Photoactive Anatase Titania, Suresh Pillai, Declan Mccormack, John Colreavy

Articles

No abstract provided.

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Mesophase Separation And Probe Dynamics In Protein-Polyelectrolyte Coacervates, A. Basak Kayitmazer, Himadri B. Bohidar, Kevin W. Mattison, Arijit Bose, Jayashri Sarkar, Akihito Hashidzume, Paul S. Russo, Werner Jaeger, Paul L. Dubin Jan 2007

Mesophase Separation And Probe Dynamics In Protein-Polyelectrolyte Coacervates, A. Basak Kayitmazer, Himadri B. Bohidar, Kevin W. Mattison, Arijit Bose, Jayashri Sarkar, Akihito Hashidzume, Paul S. Russo, Werner Jaeger, Paul L. Dubin

Chemical, Biomolecular, and Materials Engineering Faculty Publications

Protein–polyelectrolyte coacervates are self-assembling macroscopically monophasic biomacromolecular fluids whose unique properties arise from transient heterogeneities. The structures of coacervates formed at different conditions of pH and ionic strength from poly(dimethyldiallylammonium chloride) and bovine serum albumin (BSA), were probed using fluorescence recovery after photobleaching. Measurements of self-diffusion in coacervates were carried out using fluorescein-tagged BSA, and similarly tagged Ficoll, a non-interacting branched polysaccharide with the same size as BSA. The results are best explained by temporal and spatial heterogeneities, also inferred from static light scattering and cryo-TEM, which indicate heterogeneous scattering centers of several hundred nm. Taken together with previous dynamic …

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Functionalized Polymeric Membranes For Bioseparation And Biocatalysis, Saurav Datta Jan 2007

Functionalized Polymeric Membranes For Bioseparation And Biocatalysis, Saurav Datta

Theses and Dissertations--Chemical and Materials Engineering

Functionalized polymeric membrane based techniques are becoming increasingly popular in biotechnology, food and pharmaceutical industries due to their versatility and hydrodynamic benefits over traditional materials and methods. This research work has been directed towards the development of functionalized polymeric membranes, extensive experimental and theoretical analyses of some of the fundamental aspects of accessibility, membrane fouling and enzyme catalysis, and applications in affinity based bioseparation and biocatalysis. In this research work, the impact of different types of functionalization techniques, such as functionalization of different membrane materials, covalent and electrostatic immobilization, on interaction of various biomolecules and active sites in membrane has …

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Simulation Study Evaluating Alternative Initial Responses To Formation Fluid Influx During Managed Pressure Drilling, Asis Kumar Das Jan 2007

Simulation Study Evaluating Alternative Initial Responses To Formation Fluid Influx During Managed Pressure Drilling, Asis Kumar Das

LSU Master's Theses

Managed pressure drilling is an innovative technique to precisely manage wellbore pressure. It is particularly applicable for reducing the risk of a kick or lost returns when drilling with a narrow window between pore pressure and fracture pressure. The constant bottomhole pressure method of managed pressure drilling uses annular frictional pressure and choke pressure in addition to mud hydrostatic pressure to achieve precise wellbore pressure control. This project investigated alternative initial responses to kicks to determine which would be most effective and reliable under different well scenarios when applying the constant bottomhole pressure method of managed pressure drilling. Three different …

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Using Computational Fluid Dynamics Modeling To Improve The Performance Of A Solar Co2 Converter, Thomas H. Fletcher, Ralph J. Price, Reed J. Jensen Jan 2007

Using Computational Fluid Dynamics Modeling To Improve The Performance Of A Solar Co2 Converter, Thomas H. Fletcher, Ralph J. Price, Reed J. Jensen

Faculty Publications

A solar collector to convert CO2 to CO at high temperature was previously developed, achieving a product with 4-6 mol % CO from pure CO2. Modeling results showed that reactions occurred in the thermal boundary layer of the heated zirconia rod at temperatures greater than 2300 K. This paper describes results of computer modeling of advanced designs meant to increase the conversion of CO from CO2. Several design modifications were tested using the model, including changing the cool-down region configuration, increasing the zirconia rod diameter, and changing the zirconia rod shape. Several operational adjustments were also modeled, including reducing the …

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Model Compound Study Of The Pathways For Aromatic Hydrocarbon Formation In Soot, Randall E. Winans, Nancy A. Tomczyk, Jerry E. Hunt, Mark S. Solum, Ronald J. Pugmire, Thomas H. Fletcher Jan 2007

Model Compound Study Of The Pathways For Aromatic Hydrocarbon Formation In Soot, Randall E. Winans, Nancy A. Tomczyk, Jerry E. Hunt, Mark S. Solum, Ronald J. Pugmire, Thomas H. Fletcher

Faculty Publications

As a follow-up of previous work on the flame pyrolysis of biphenyl and pyrene, a more detailed analysis of the pyrolytic products has been done using additional NMR data obtained on the whole soot sample correlated with detailed high-resolution and GC mass spectrometry data on the solvent-extracted portion of the same samples. These latter data complement the earlier NMR data with details of the pre-sooting structures, referred to as “young soot”, in pyrolyzed biphenyl samples collected at 1365, 1410, and 1470 K and pyrene at 1410 and 1470 K. The data reveal the roles played by free-radical-assisted polymerization reactions as …

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Performance Of Aerobic Bioreactors During Treatment Of Tanning Industry Wastewater, Samwel V. Manyele Dec 2006

Performance Of Aerobic Bioreactors During Treatment Of Tanning Industry Wastewater, Samwel V. Manyele

Tanzania Journal of Engineering and Technology (TJET)

The performance of aerobic bioreactors loaded with novel biomass support (the KMT® support particles) during the treatment of tanning industry wastewater is presented in this paper. The wastewater samples were collected from TANWAT Company in Njombe, which extracts tannins from barks of the wattle tree. The wastewater generated from T ANWAT is very acidic with high loading of organic compounds, which are very complex and difficult to biodegrade using conventional methods. The paper introduces a new technology for treatment of heavily loaded industrial wastewater, like tannins, that is the Three-Phase Fluidized Bed Bioreactor (TPFBB) which utilizes the KM'f® support particles. …

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Geometric Programming As A General Method For Phase And Reaction Equilibrium Calculations, Godwill Mrema Dec 2006

Geometric Programming As A General Method For Phase And Reaction Equilibrium Calculations, Godwill Mrema

Tanzania Journal of Engineering and Technology (TJET)

Geometric programming has been used to calculate a large mtmber ofdifferent ideal and non-ideal equilibria, including, for reaction and For non-ideal Systems the primal program is solved a number Of times With the nan-ideal terms fixed each time. After each primal solution, the nan-ideal terms are "'hdated using the corresponding dun! solution. This iteration generally converges. We have included one counter-example, where the failure is caused by the equation Of state, which Cannot giu• correct roots.

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Statistical Methods For Kinetic Modeling Of Fischer Tropsch Synthesis On A Supported Iron Catalyst, Brian L. Critchfield Dec 2006

Statistical Methods For Kinetic Modeling Of Fischer Tropsch Synthesis On A Supported Iron Catalyst, Brian L. Critchfield

Theses and Dissertations

Fischer-Tropsch Synthesis (FTS) is a promising technology for the production of ultra-clean fuels and chemical feedstocks from biomass, coal, or natural gas. Iron catalysts are ideal for conversion of coal and biomass. However, precipitated iron catalysts used in slurry-bubble column reactors suffer from high attrition resulting in difficulty separating catalysts from product and increased slurry viscosity. Thus, development of an active and selective-supported iron catalyst to manage attrition is needed. This thesis focuses on the development of a supported iron catalyst and kinetic models of FTS on the catalyst using advanced statistical methods for experimental design and analysis. A high …

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Investigation Of Flow And Microstructure In Rheometric And Processing Flow Conditions For Liquid Crystalline Pitch, Santanu Kundu Dec 2006

Investigation Of Flow And Microstructure In Rheometric And Processing Flow Conditions For Liquid Crystalline Pitch, Santanu Kundu

All Dissertations

A fundamental understanding of flow and its influence on the microstructure is required to obtain carbon materials with desired properties. The objective of this research was to investigate the flow and microstructural behavior of a synthetic mesophase pitch (AR-HP) in rheometric and processing flow conditions. In addition, simulation studies were performed to establish a frame work for modeling the flow behavior of this complex material in different flow situations.
The steady-shear viscosities obtained from a cone-plate rheometer during increasing rate-sweep experiments exhibited a shear-thinning region (Region I) with a slope of about -0.2 and a plateau (Region II) region. The …

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Facilitated Effect Of Ag To Oxygen Transportation In Pem Fuel Cell Air Cathodes, Hong-Feng Xu, Jian-Hua Dong, Xiang-Li Hou Nov 2006

Facilitated Effect Of Ag To Oxygen Transportation In Pem Fuel Cell Air Cathodes, Hong-Feng Xu, Jian-Hua Dong, Xiang-Li Hou

Journal of Electrochemistry

Silver(Ag) was deposited in the pores of Nafion membrane by ion exchange and succedent hydrogen reduction;the structures of Nafion-Ag membrane were measured by TEM and XRD,the diffusion coefficients of oxygen in Nafion-Ag was determined by electrochemical limited current method.The results showed that after deposited silver,the pores in the Nafion were enlarged by silver grains;the oxygen diffusion coefficient was increased about four times.By introducing silver in the thin Nafion film around the cathode catalyst,the performance of PEM fuel cell have a evident increasing in high current density, which shows the facilitated effects of silver to oxygen transportation in PEM fuel cell.

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Synthesis Of Monolithic Carbon/Nickel Oxide Composite Electrode Material And Cyclic Voltammetry Characteristics, Tian-Ying Guo, Jing-Wei Zhu, Mou-Dao Song, Bang-Hua Zhang Nov 2006

Synthesis Of Monolithic Carbon/Nickel Oxide Composite Electrode Material And Cyclic Voltammetry Characteristics, Tian-Ying Guo, Jing-Wei Zhu, Mou-Dao Song, Bang-Hua Zhang

Journal of Electrochemistry

Monolithic carbon/nickel oxide composite materials were synthesized by carbonization of phenol formaldehyde gels that were ion-exchanged with Ni2+.Atomic absorption spectroscopy and powder X-ray diffraction technique were used to characterize the chemical composition and physical structure of the materials.The nickel dope amount for this method can reach 5.9 %(by mass).Subsequent cyclic voltammetry experiments indicate that the materials exhibit best capacitive performance at the nickel content of 4.4 %.

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Novel Electrochemical Method For Synthesis Of Nanostructured Materials Of Noble Metals Based On Poly(N-Vinylpyrrolidone) (Pvp), Wei Pan, Xiao-Kai Zhang, Ming-Hu Huang, Shao-Xin Huang, Xing-Li Feng, Hou-Yi Ma Nov 2006

Novel Electrochemical Method For Synthesis Of Nanostructured Materials Of Noble Metals Based On Poly(N-Vinylpyrrolidone) (Pvp), Wei Pan, Xiao-Kai Zhang, Ming-Hu Huang, Shao-Xin Huang, Xing-Li Feng, Hou-Yi Ma

Journal of Electrochemistry

Gold nanocrystals with controllable size were synthesized through a simple electroreduction method using poly(N-vinylpyrrolidone)(PVP) of different polymerization degree as both stabilizer and shape-controller for gold nanoclusters.Individual gold nanoparticles spontaneously assembled into the wire-and ring-shaped nanoparticle aggregates depending on the PVP's dynamic stretching and curling,and precursor nanoparticles grew into flat,single-crystalline nanoprisms with thickness of dozens of nanometers based on the oriented aggregation between particles.Besides,core-shell Au/Ag nanoparticles were conveniently synthesized through two-step electroreduction of noble metal ions in the presence of PVPK30.The electrochemical synthetic method based on PVP provides a new path for preparation of noble metal nanostructured materials with different shape …

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Study Of The Electrooxidation Of Glycerol On Oxide And Pd/C Composite Catalysts, Zhi-Yuan Yan, Chang-Wei Xu, Pei-Kang Shen Nov 2006

Study Of The Electrooxidation Of Glycerol On Oxide And Pd/C Composite Catalysts, Zhi-Yuan Yan, Chang-Wei Xu, Pei-Kang Shen

Journal of Electrochemistry

Oxide and Pd on carbon composite catalysts have been prepared by intermittent microwave heating(IMH) method.The performance of the catalysts for glycerol oxidation in alkaline solution is studied by electrochemical techniques.It is shown that the Pd/C catalyst is active for glycerol electrooxidation.However,the oxide-Pd/C catalysts are even better in terms of the onset potential that is more negative and peak current density.The ratio of oxide to Pd is optimized according to the electrochemical measurement.The results reveal that the addition of oxide into the Pd/C induces the synergistic effect for glycerol electrooxidation.

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Deposition Of Metallic Nanoparticles On Carbon Nanotubes Via A Fast Evaporation Process, Guoqiang Ren, Yangchuan Xing Nov 2006

Deposition Of Metallic Nanoparticles On Carbon Nanotubes Via A Fast Evaporation Process, Guoqiang Ren, Yangchuan Xing

Chemical and Biochemical Engineering Faculty Research & Creative Works

A new technique was developed for the deposition of colloidal metal nanoparticles on carbon nanotubes. It involves fast evaporation of a suspension containing sonochemically functionalized carbon nanotubes and colloidal nanoparticles. It was demonstrated that metallic nanoparticles with different sizes and concentrations can be deposited on the carbon nanotubes with only a few agglomerates. the technique does not seem to be limited by what the nanoparticles are, and therefore would be applicable to the deposition of other nanoparticles on carbon nanotubes. PtPd and CoPt3 alloy nanoparticles were used to demonstrate the deposition process. It was found that the surfactants used to …

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The Synthesis, Structure And Electrochemical Performances Of Lithium Iron Phosphate, Hui Xie, Zhen-Tao Zhou Nov 2006

The Synthesis, Structure And Electrochemical Performances Of Lithium Iron Phosphate, Hui Xie, Zhen-Tao Zhou

Journal of Electrochemistry

The lithium iron phosphate cathode materials were synthesized by solid-state reaction combined high-rate ball milling under the temperature ranging from 400 ℃ to 700 ℃.The crystalline structure, morphology of particles, and electrochemical performance of the sample were investigated by X-ray diffraction, scanning electron microscopy and charge-discharge test. The results showed that the sintering temperature had great influences on the crystal structure, morphology and electrochemical performances of LiFePO4. The sample synthesized under 600℃ showed the best charge-discharge performances with the first specific discharge capacity of(128.8) mAh/g and the 15th specific discharge capacity of 129.1 mAh/g at 0.1C rate, …

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Structure And Electrochemical Characteristics Of Lifepo4 Prepared By The Polyacrylates-Pyrolysis-Reduction Method For Li-Ion Batteries, Li-Hong Yu, Yu-Liang Cao, Xiao-Fei Zhang, Han-Xi Yang, Xin-Ping Ai Nov 2006

Structure And Electrochemical Characteristics Of Lifepo4 Prepared By The Polyacrylates-Pyrolysis-Reduction Method For Li-Ion Batteries, Li-Hong Yu, Yu-Liang Cao, Xiao-Fei Zhang, Han-Xi Yang, Xin-Ping Ai

Journal of Electrochemistry

The cathode material of olivine LiFePO4 was prepared by a novel method of polyacrylate-pyrolysis-reduction.XRD demonstrates that the material have the olivine structure.SEM photo shows an average particle-size of about 100 nm with a well distribution.Electrochemical test of cycling at a constant current reveals the discharge capacity of 138 mAh/g and a good cycling stability.It is a novel practicable technology to prepare LiFePO4 by using polyacrylate-pyrolysis-reduction method.

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Biogasoline Production From Palm Oil Via Catalytic Hydrocracking Over Gamma-Alumina Catalyst, Anondho Wijanarko, Dadi Ahmad Mawardi, Mohammad Nasikin Nov 2006

Biogasoline Production From Palm Oil Via Catalytic Hydrocracking Over Gamma-Alumina Catalyst, Anondho Wijanarko, Dadi Ahmad Mawardi, Mohammad Nasikin

Makara Journal of Technology

Biogasoline Production from Palm Oil Via Catalytic Hydrocracking over Gamma-Alumina Catalyst. Bio gasoline conversion from palm oil is an alternative energy resources method which can be substituted fossil fuel base energy utilization. Previous research resulted that palm oil can be converted into hydrocarbon by catalytic cracking reaction with γ-alumina catalyst. In this research, catalytic cracking reaction of palm oil by γ-alumina catalyst is done in a stirrer batch reactor with the oil/catalyst weight ratio variation of 100:1, 75:1, and 50:1; at suhue variation of 260 to 340oC and reaction time variation of 1 to 2 hour. Post cracking reaction, bio …

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Segmental Sinusoidal Model For Speech Signal Coding, Florentinus Budi Setiawan, Soegijardjo Soegijoko, Sugihartono Sugihartono, Suhartono Tjondronegoro Nov 2006

Segmental Sinusoidal Model For Speech Signal Coding, Florentinus Budi Setiawan, Soegijardjo Soegijoko, Sugihartono Sugihartono, Suhartono Tjondronegoro

Makara Journal of Technology

Segmental Sinusoidal Model for Speech Signal Coding. Periodic signal can be decomposed by sinusoidal component with Fourier series. With this characteristic, it can be modeled referring by sinusoidal form. By the sinusoidal model, signal can be quantized in order to encode the speech signal at the lower rate. The recent sinusoidal method is implemented in speech coding. By using this method, a block of the speech signal with 20 ms to 30 ms width is coded based on Fourier series coefficients. The new method proposed is quantization and reconstruction of speech signal by the segmental sinusoidal model. A segment is …

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A Study On Parallel Computation Tools On Networked Pcs, Heru Suhartanto Nov 2006

A Study On Parallel Computation Tools On Networked Pcs, Heru Suhartanto

Makara Journal of Technology

A Study on Parallel Computation Tools on Networked PCs. Many models for natural phenomena, engineering applications and industries need powerfull computing resources to solve their problems. High Performance Computing resources were introduced by many researchers. This comes in the form of Supercomputers and with operating systems and tools for development such as parallel compiler and its library. However, these resources are expensive for the investation and maintenance, hence people need some alternatives. Many people then introduced parallel distributed computing by using available computing resource such as PCs. Each of these PCs is treated as a processors, hence the cluster of …

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Crude Oil Sludge Degradation In Microcosmic Scale: Simple Simulation As Preliminary Study On Land Treatment Bioremediation., Astri Nugroho Nov 2006

Crude Oil Sludge Degradation In Microcosmic Scale: Simple Simulation As Preliminary Study On Land Treatment Bioremediation., Astri Nugroho

Makara Journal of Technology

Crude Oil Sludge Degradation in Microcosmic Scale: Simple Simulation as Preliminary Study on Land Treatment Bioremediation. A study in microcosmic condition has been carried out to evaluate the bacterial hydrocarbonoclastic capability in increasing the oil sludge degradation being mixed with NPK fertilizer as nitrogen resources. Aerobic test was carried out by putting erlenmeyers in a shaker incubator, 120 rpm shaking speed, at 50°C temperature. While 150 days in microcosmic one observation showed that the consortium has the potential to grow up to 50% (v/v) sludge oil load. Maximum growth and maximum growth rate of the consortium occurred in the III …

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Determination Of Operation Condition And Product Dimension Accuracy Optimization Of Filament Deposition Modelling On Layer Manufacturing Application, Slamet A. Widyanto, Alva Edy Tontowi, Jamasri Jamasri, Heru Santoso Budi Rochardjo Nov 2006

Determination Of Operation Condition And Product Dimension Accuracy Optimization Of Filament Deposition Modelling On Layer Manufacturing Application, Slamet A. Widyanto, Alva Edy Tontowi, Jamasri Jamasri, Heru Santoso Budi Rochardjo

Makara Journal of Technology

Layer manufacturing process has proven as a process that can produce a high complexity mechanical part. Now, Improvement of LM methods continuously conduct that is aimed to increase precessions and efficiency of these processes. Pressure filament deposition modelling is a form of layer manufacturing process that is designed to produce a plastic part with controlling its semisolid phase. In this research, the equipment of filament depositor is designed and tested to make the product filament deposition. With operation condition observation, the optimal temperature and pressure of deposition process was determined. These experiments used PVC as crystalline material and polypropylene as …

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Magnetic Field Effects On Caco3 Precipitation Process In Hard Water, Nelson Saksono, Setijo Bismo, Elsa Krisanti, Azwar Manaf, Roekmijati Widaningrum Nov 2006

Magnetic Field Effects On Caco3 Precipitation Process In Hard Water, Nelson Saksono, Setijo Bismo, Elsa Krisanti, Azwar Manaf, Roekmijati Widaningrum

Makara Journal of Technology

Magnetic Field Effects on CaCO3 Precipitation Process in Hard Water. Magnetic treatment is applied as physical water treatment for scale prevention especially CaCO3, from hard water in piping equipment by reducing its hardness. Na2CO3 and CaCl2 solution sample was used in to investigate the magnetic fields influence on the formation of particle of CaCO3. By changing the strength of magnetic fields, exposure time and concentration of samples solution, this study presents quantitative results of total scale deposit, total precipitated CaCO3 and morphology of the deposit. This research was run by comparing magnetically and non-magnetically treated samples. The results showed an …

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Stress Corrosion Cracking Behavior Of Stainless Steel 304 In The Sulfuric Acid Environment Due To Prestrain, Mohammad Badaruddin, Ahmad Suudi, Arinal Hamni Nov 2006

Stress Corrosion Cracking Behavior Of Stainless Steel 304 In The Sulfuric Acid Environment Due To Prestrain, Mohammad Badaruddin, Ahmad Suudi, Arinal Hamni

Makara Journal of Technology

Stress Corrosion Cracking Behavior of Stainless Steel 304 in the Sulfuric Acid Environment Due to Prestrain. The aim of research is to investigate the effect of prestrain on the stress corossion cracking behavior of AISI 304 stainless steel in the sulfuric acid of 10% concentration under the static cantilever loading according to ASTM E-1681 standart. The specimen of 304 Stainless steel was strain up over the yield strength until reaching the uniform strain of 5% and 10% using servopulser UTM 9506 under the displacement control of 0,3 mm/sec. The results of test show that the prestrain of 5% specimen is …

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Santa Clara County Soft First Story Multi Unit Building Survey, Guna S. Selvaduray, S. Vukazich, J. Tran Nov 2006

Santa Clara County Soft First Story Multi Unit Building Survey, Guna S. Selvaduray, S. Vukazich, J. Tran

Faculty Publications

The objective of this survey was to provide data to emergency managers in Santa Clara County on the number of soft first-story multifamily dwellings (MFD) located in their communities using a cost-effective town-gown partnership. Target areas of cities were found by identifying areas containing residential units of two or more stories that had four or more living units. The survey found that 2,630, or 36%, of the 7,391 MFD in Santa Clara County are of the soft first-story construction type. It was found that one out of every nine apartment units in Santa Clara County is located in a soft …

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Improving Database Quality Through Eliminating Duplicate Records, Mingzhen Wei, Andrew H. Sung, Martha E. Cather Nov 2006

Improving Database Quality Through Eliminating Duplicate Records, Mingzhen Wei, Andrew H. Sung, Martha E. Cather

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Redundant or duplicate data are the most troublesome problem in database management and applications. Approximate field matching is the key solution to resolve the problem by identifying semantically equivalent string values in syntactically different representations. This paper considers token-based solutions and proposes a general field matching framework to generalize the field matching problem in different domains. By introducing a concept of String Matching Points (SMP) in string comparison, string matching accuracy and efficiency are improved, compared with other commonly-applied field matching algorithms. The paper discusses the development of field matching algorithms from the developed general framework. The framework and corresponding …

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Nonquiescent Relaxation In Entangled Polymer Liquids After Step Shear, Shi-Qing Wang, Sham Ravindranath, Pouyan Boukany, Michael Olechnowicz, Roderic P. Quirk, Jimmy Mays Nov 2006

Nonquiescent Relaxation In Entangled Polymer Liquids After Step Shear, Shi-Qing Wang, Sham Ravindranath, Pouyan Boukany, Michael Olechnowicz, Roderic P. Quirk, Jimmy Mays

College of Polymer Science and Polymer Engineering

Large step shear experiments revealed through particle tracking velocimetry that entangled polymeric liquids display either internal macroscopic movements upon shear cessation or rupturelike behavior during shear. Visible inhomogeneous motions were detected in five samples with the number of entanglements per chain ranging from 20 to 130 at amplitudes of step strain as low as 135%.

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Procedure To Quantify Biofilm Activity In Carriers Used In Wastewater Treatment Systems, James Bolton, Archana Tummala, Chirag Kapadia, Manoj Dandamudi, Joanne M. Belovich Nov 2006

Procedure To Quantify Biofilm Activity In Carriers Used In Wastewater Treatment Systems, James Bolton, Archana Tummala, Chirag Kapadia, Manoj Dandamudi, Joanne M. Belovich

Chemical & Biomedical Engineering Faculty Publications

A procedure is presented for evaluating and comparing the biological activity of biofilms attached to various biofilm carriers by measurement of the glucose consumption rate. This technique allows for the economical design and selection of small particulate biofilm carriers that will maximize substrate removal when used in industrial-scale fluidized bioreactors. Methods for ensuring reproducible results are described. To support the glucose consumption rate findings, biofilm dry weights were obtained at the conclusion of activity rate experiments, and scanning electron micrographs were taken to evaluate the presence of biofilm and to view surface characteristics. Fourteen different biofilm carriers were evaluated ranging …

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On One-Dimensional Self-Assembly Of Surfactant-Coated Nanoparticles, Jee-Ching Wang, Partho Neogi, Daniel Forciniti Nov 2006

On One-Dimensional Self-Assembly Of Surfactant-Coated Nanoparticles, Jee-Ching Wang, Partho Neogi, Daniel Forciniti

Chemical and Biochemical Engineering Faculty Research & Creative Works

Nanometer-sized metal and semiconductor particles possess novel properties. To fully realize their potential, these nanoparticles need to be fabricated into ordered arrays or predesigned structures. A promising nanoparticle fabrication method is coupled surface passivation and self-assembly of surfactant-coated nanoparticles. Due to the empirical procedure and partially satisfactory results, this method still represents a major challenge to date and its refinement can benefit from fundamental understanding. Existing evidences suggest that the self-assembly of surfactant-coated nanoparticles is induced by surfactant-modified interparticle interactions and follows an intrinsic road map such that short one-dimensional (1D) chain arrays of nanoparticles occur first as a stable …

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Enzyme–Microbe Synergy During Cellulose Hydrolysis By Clostridium Thermocellum, Yanpin Lu, Yi-Heng P. Zhang, Lee R. Lynd Oct 2006

Enzyme–Microbe Synergy During Cellulose Hydrolysis By Clostridium Thermocellum, Yanpin Lu, Yi-Heng P. Zhang, Lee R. Lynd

Dartmouth Scholarship

Specific cellulose hydrolysis rates (g of cellulose/g of cellulase per h) were shown to be substantially higher (2.7- to 4.7-fold) for growing cultures of Clostridium thermocellum as compared with purified cellulase preparations from this organism in controlled experiments involving both batch and continuous cultures. This “enzyme–microbe synergy” requires the presence of metabolically active cellulolytic microbes, is not explained by removal of hydrolysis products from the bulk fermentation broth, and appears due to surface phenomena involving adherent cellulolytic microorganisms. Results support the desirability of biotechnological processes featuring microbial conversion of cellulosic biomass to ethanol (or other products) in the absence of …

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