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Full-Text Articles in Engineering

The Kinetics Of A Palladium Precursor – Tobacco Mosaic Virus Reaction, Adi Banerjee, Mayo Adigun, Michael T. Harris Aug 2014

The Kinetics Of A Palladium Precursor – Tobacco Mosaic Virus Reaction, Adi Banerjee, Mayo Adigun, Michael T. Harris

The Summer Undergraduate Research Fellowship (SURF) Symposium

There have been numerous developments in the field of production of metallic nanoparticles using biotemplates such as the Tobacco Mosaic Virus (TMV). Past research has looked at the conditions required to maximise nanoparticle formation. This study of the kinetics of a nanomaterial synthesis reaction using a biotemplate would elucidate the understanding of the controlled growth of nanoparticles, which can be applied in the fabrication of photocatalysts, electrical nanocircuits and solar cells. This study specifically focuses on the reaction between a palladium precursor and the TMV without an external reducing agent, where the palladium ion concentration is measured over time using …


Stability Of Aqueous Dispersions Of Titanium Dioxide Against Sedimentation And Aggregation, Guanrong Bai, Xilan Zhu, Elias I. Franses, David S. Corti, Yung-Jih Yang Aug 2014

Stability Of Aqueous Dispersions Of Titanium Dioxide Against Sedimentation And Aggregation, Guanrong Bai, Xilan Zhu, Elias I. Franses, David S. Corti, Yung-Jih Yang

The Summer Undergraduate Research Fellowship (SURF) Symposium

Particles of titanium dioxide (TiO2) are widely used as white pigments in paints and inks, due to their brightness and high refractive index. Yet, with TiO2 having a high density (4.2 g/cm3), particles with typical sizes of 300 nm sediment rapidly even before significant agglomeration can occur. Thus, increasing the stability of TiO2 dispersions against sedimentation as well as aggregation is important. We studied the effect of sodium dodecyl sulfate (SDS), a commonly used dispersant, on the stability of aqueous dispersions of TiO2 with weight fractions from 0.01 to 40. The sedimentation time of …


Formulation And Solution Of Contingency Constrained Acopf Problem With Pyomo, Stefanus D. Winarto, Jianfeng Liu, Carl D. Laird Aug 2014

Formulation And Solution Of Contingency Constrained Acopf Problem With Pyomo, Stefanus D. Winarto, Jianfeng Liu, Carl D. Laird

The Summer Undergraduate Research Fellowship (SURF) Symposium

Power grids scattered around the world bring great importance to society as they are challenged to provide economically efficient and reliable power market. With consideration of possible system contingency, which refers to multi-scenario optimization where each scenario considers an individual transmission element failure, the determination of optimal generators’ set points in the transmission network is becoming even more essential and challenging. A problem formulation is developed to solve the optimal allocation and minimize the total operating cost for the nominal case while including a large number of contingency scenarios. To achieve that goal, traditional ACOPF (AC optimal power flow model) …


The Catalysis Of Delayed Petroleum Coking, Anya M. Heinimann, Robert Khakimov, Hyun-Tae Hwang, Enrico N. Martinez Aug 2014

The Catalysis Of Delayed Petroleum Coking, Anya M. Heinimann, Robert Khakimov, Hyun-Tae Hwang, Enrico N. Martinez

The Summer Undergraduate Research Fellowship (SURF) Symposium

Due to the decreasing crude oil quality (heavier crudes and increasing contaminant concentrations) methods for upgrading residues from the refining process, such as coking, are becoming increasingly important. Delayed coking, a method by which residues are thermally cracked (large heavy molecules broken into smaller lighter molecules), produces liquid products and solid coke which can both be sold for further profit. In order to increase the amount of liquid products produced since they are the most value added product of the coking process catalysts (platinum on 0.5% alumina and nickel (skeletal),molybdenum promoted (1 wt%)) were tested to see how they would …


Population Balance Modeling Of Conjugation In Enterococcus Faecalis, Jeremy Binagia, Vu Tran, Che-Chi Shu, Doraiswami Ramkrishna Aug 2014

Population Balance Modeling Of Conjugation In Enterococcus Faecalis, Jeremy Binagia, Vu Tran, Che-Chi Shu, Doraiswami Ramkrishna

The Summer Undergraduate Research Fellowship (SURF) Symposium

In the bacteria species Enterococcus faecalis, transfer of plasmid pCF10 by conjugation between donor cells that possess sets of genes conferring drug resistance and recipient cells leads to the spread of this resistance in a population. A complex signaling molecule network is responsible for communication between recipient and donor cells. Up to this point, the nature of these signaling molecules has been modeled deterministically from the point of view of an “average” cell. While this view has been cured slightly by stochastic treatments, a model is needed that better accounts for the individual nature of each cell, each cell’s interactions …


Effect Of Twin Screw Granulator Process Parameters On Granule Attributes, Haosheng Xu, Ridade Sayin, James Litster Aug 2014

Effect Of Twin Screw Granulator Process Parameters On Granule Attributes, Haosheng Xu, Ridade Sayin, James Litster

The Summer Undergraduate Research Fellowship (SURF) Symposium

Twin screw wet granulation has been considered as an efficient and effective technique of manufacturing granules (agglomerates made up of small particles) and has been widely applied in pharmaceutical industry. However, narrow granule size distributions are difficult to achieve. This study aims to elucidate the effect of process parameters such as liquid feed rate and screw configuration on the granule attributes through granule characterization. The methods used are sieve analysis (for size distribution), liquid distribution (determining the dye concentration in the granules) and density and porosity (percentage gas volume in the granule) analyses. A sieve shaker is used to divide …


Characterization Of Swelling Ratio And Water Content Of Hydrogels For Cartilage Engineering Applications, Emily E. Gill, Renay S.-C. Su, Julie C. Liu Aug 2014

Characterization Of Swelling Ratio And Water Content Of Hydrogels For Cartilage Engineering Applications, Emily E. Gill, Renay S.-C. Su, Julie C. Liu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Due to the high prevalence of arthritis and cartilage-related injuries, tissue engineers are studying ways to grow cartilage tissue replacements. Resilin, an elastomeric protein found in insect cuticles, is known for its extraordinary resilience and elasticity. In previous studies, recombinant resilin-based hydrogels, or cross-linked protein networks, exhibited potential for use in cartilage tissue scaffolds. Our lab successfully developed resilin-based proteins with a sequence based on the mosquito gene and showed that resilin-based hydrogels possess mechanical properties of the same order of magnitude as native articular cartilage. In addition, these mechanical properties can be controlled by changing the protein concentration. To …


Monitoring Hydroxyurea Treatment Of Sickle Cell Anemia, Adhit Ramamurthi, Jayachandran Devaraj, Doraiswami Ramkrishna Aug 2014

Monitoring Hydroxyurea Treatment Of Sickle Cell Anemia, Adhit Ramamurthi, Jayachandran Devaraj, Doraiswami Ramkrishna

The Summer Undergraduate Research Fellowship (SURF) Symposium

Sickle cell is a hereditary disease affecting more than 100,000 people in the United States alone that causes hemoglobin in red blood cells to polymerize and turn the cell into a sickle shape, resulting in severe vaso-occlusive crises and ischemic attacks. Sickle cell patients often suffer from pain crises, with the number of pain crises linked to their prognosis, especially at a younger age. Currently, the drug hydroxyurea (HU) is used to treat the disease, with a measure of red blood cell volume (RBC MCV) as monitor for treatment progression. However, physicians have to wait atleast 120 days to identify …


Radical Polymers As Anodic Charge Extraction Layers In Small Molecule Organic Photovoltaic Devices, Krystopher S. Jochem, Aditya G. Baradwaj, Bryan W. Boudouris Aug 2014

Radical Polymers As Anodic Charge Extraction Layers In Small Molecule Organic Photovoltaic Devices, Krystopher S. Jochem, Aditya G. Baradwaj, Bryan W. Boudouris

The Summer Undergraduate Research Fellowship (SURF) Symposium

Organic photovoltaic (OPV) devices based on the copper (II) phthalocyanine(CuPc)/ fullerene(C60) system are an innovative photovoltaic technology optimal for situations requiring low-cost, transparent, and flexible devices. Furthermore, the high degree of reproducibility of this system allows for the ready study of new OPV technologies. Here, we have used this system to elucidate systematic structure-property-performance relationships for a new OPV anode modifier. The addition of interfacial modifier materials between the organic CuPc/C60 layers and the metallic anode drastically can improve efficiency. Radical polymers are a class of polymers with aliphatic backbones and pendent stabilized radical groups. Here, we …


Effect Of Sodium Dodecyl Sulfate And Sodium Chloride On The Stability Of Aqueous Dispersions Of Tio2 Particles Against Aggregation And Sedimentation, Xilan Zhu, Guanrong Bai, Elias I. Franses, David S. Corti, Yung-Jih Yang Aug 2014

Effect Of Sodium Dodecyl Sulfate And Sodium Chloride On The Stability Of Aqueous Dispersions Of Tio2 Particles Against Aggregation And Sedimentation, Xilan Zhu, Guanrong Bai, Elias I. Franses, David S. Corti, Yung-Jih Yang

The Summer Undergraduate Research Fellowship (SURF) Symposium

Dispersions of TiO2 particles are widely used as the main pigment in white inks for inkjet printers due to its brightness and high opacity. The TiO2 particles, however, have a high density, and so the possible fast settling of these particles can cause maintenance problems for the printers and lower the printing quality. We studied the effect of sodium dodecyl sulfate (SDS), a commonly used dispersant, on the stability of 1 wt% TiO2 aqueous dispersions, both with and without NaCl, against aggregation and sedimentation. The sedimentation half time (t50), defined as the time need for the particles to …


Synthesis And Characterization Of Microporous And Mesoporous Catalysts For Shale Gas Upgrading, Danesh Contractor, Ravi Joshi, Rajamani Gounder Aug 2014

Synthesis And Characterization Of Microporous And Mesoporous Catalysts For Shale Gas Upgrading, Danesh Contractor, Ravi Joshi, Rajamani Gounder

The Summer Undergraduate Research Fellowship (SURF) Symposium

The petroleum industry is gradually shifting from using naphtha to ethane as its feedstock and new ethane steam crackers are being built. Using ethane as a feedstock produces more ethene and less co-products such as propene, aromatics and C4 alkenes. Thus, the shift in feedstock will reduce the availability of these co-products. Developing methods for the interconversion of alkenes, and specifically using ethene as a reactant, can solve this problem.

This project focuses on synthesis and characterization of zeolites with the BEA framework topology, and their nickel exchanged versions as potential ethene dimerization catalysts. In future work, these materials will …


The Role Of Surface Area In Catalytic Gasification Of Biomass, Elizabeth A. Wachs, Nitish Kumar, Indraneel Sircar, Prithviraja Basak, Jay P. Gore Phd Aug 2014

The Role Of Surface Area In Catalytic Gasification Of Biomass, Elizabeth A. Wachs, Nitish Kumar, Indraneel Sircar, Prithviraja Basak, Jay P. Gore Phd

The Summer Undergraduate Research Fellowship (SURF) Symposium

Gasification of biomass has the potential to provide a carbon-negative source of liquid fuels. The current limited use of gasification is due in part to the high temperatures necessary to achieve high conversion levels. These temperatures can be lowered by the use of catalysts, but the mechanisms by which catalysts affect the reaction rate are not fully understood. Here, the structural component of potassium carbonate’s role in the gasification process was examined. Samples of pinewood sawdust were impregnated with potassium carbonate, then pyrolyzed with N2 in a fixed bed reactor at 750°C (heater thermocouple reading). Half of the char was …


Synthesis And Thermoelectric Properties Of Cusbs2, Tianyue Gao, Haiyu Fang, Yue Wu Aug 2014

Synthesis And Thermoelectric Properties Of Cusbs2, Tianyue Gao, Haiyu Fang, Yue Wu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Copper antimony sulfide, CuSbS2 nanoparticles have a large potential of being a good thermoelectric material because they are made up of earth abundant elements. Thermoelectric materials can convert thermal energy into electricity, so that the wasted energy can be saved. Also, by using this earth abundant material, we can make thermoelectric materials much cheaper. The hypothesis of this study is that CuSbS2 could have a large Seebeck coefficient, one of the most important factors of thermoelectric materials, because of the complexity of its band structure. The other hypothesis is that thermal transport could be significantly suppressed through nanostructuring. There are …


Communication: Using Multiple Tethers To Stabilize Proteins On Surfaces, Brandon K. Loong, Thomas A. Knotts Iv Aug 2014

Communication: Using Multiple Tethers To Stabilize Proteins On Surfaces, Brandon K. Loong, Thomas A. Knotts Iv

Faculty Publications

Protein surface interactions are important in many applications in biotechnology including protein arrays, but these technologies have not lived up to their transformative potential because it is difficult to attach proteins to surfaces in a manner that preserves function and theoretical understanding of the relevant phenomena remains limited. Here is reported the effect of using multiple tethers to attach a protein (lysozyme) to a surface and the effects on the structure and stability of the molecule. The simulations show how using two tethers can drastically change the folding mechanism such that a protein that is initially unstable and inactive when …


Adjustable Resonance Frequency Of Rf-Mems Capacitor By Using Comb- Drive Actuators: A Design Approaches, Agus Santoso Tamsir, Sandy Tannu Wijaya, Dato’ Burhanuddin Yeop Majlis Aug 2014

Adjustable Resonance Frequency Of Rf-Mems Capacitor By Using Comb- Drive Actuators: A Design Approaches, Agus Santoso Tamsir, Sandy Tannu Wijaya, Dato’ Burhanuddin Yeop Majlis

Makara Journal of Technology

The needs of smaller size RF varactor is a must today, and MEMS comes to be the potential one. In this paper we proposed an adjustable resonance RF-MEMS varactor by using comb-drive actuators placing in each side of the square movable plate. In our preliminary simulation, we found that the device can work properly but some constraints comes such as the dominancies of harmonic resonance frequencies that influences into the nominal capacitances. Therefore for the next step of development we have to find out the window of the structural dimension for a certain spans and a certain operating frequencies.


Make Or Buy Analysis Model Based On Tolerance Design To Minimize Manufacturing Cost And Quality Loss, Cucuk Nur Rosyidi, Reza Rizkichani Akbar, Wakhid Ahmad Jauhari Aug 2014

Make Or Buy Analysis Model Based On Tolerance Design To Minimize Manufacturing Cost And Quality Loss, Cucuk Nur Rosyidi, Reza Rizkichani Akbar, Wakhid Ahmad Jauhari

Makara Journal of Technology

In a manufacturing company, manufacturing costs, or component prices, and tolerance will affect the price and the quality of a product. Companies must produce high-quality products with low manufacturing costs in order to keep their products competitive in the market; however, it is difficult to produce a high-quality product with a low manufacturing cost. Companies have difficulties in determining the components to be produced using their own manufacturing facilities (make) or outsourced to their suppliers (buy). Hence, a make or buy analysis is needed to minimize the manufacturing costs and quality loss and to determine the optimum alternative regarding make …


Observation Of Tunneling Effects In Lateral Nanowire Pn Junctions, Sri Purwiyanti, Arief Udhiarto, Daniel Moraru, Takeshi Mizuno, Djoko Hartanto, Michiharu Tabe Aug 2014

Observation Of Tunneling Effects In Lateral Nanowire Pn Junctions, Sri Purwiyanti, Arief Udhiarto, Daniel Moraru, Takeshi Mizuno, Djoko Hartanto, Michiharu Tabe

Makara Journal of Technology

As electronic device dimensions are continuously reduced, applied bias conditions significantly change and the transport mechanisms must be reconsidered. Tunneling devices are promising for scaled-down electronics because of expected high-speed operation and relatively low bias. In this work, we investigated the tunneling features in silicon-oninsulator lateral nanowire pn junction and pin junction devices. By controlling the substrate voltage, tunneling features can be observed in the electrical characteristics. We found that the minimum substrate voltage required for tunneling to occur in pn junctions is higher as compared with pin junctions. The main cause of these effects relies in the difference between …


Argon Ion Irradiation Effect On The Magnetic Properties Of Fe-Al2o3 Nano Granular Film, Setyo Purwanto, Isao Sakamoto Aug 2014

Argon Ion Irradiation Effect On The Magnetic Properties Of Fe-Al2o3 Nano Granular Film, Setyo Purwanto, Isao Sakamoto

Makara Journal of Technology

We studied the effect of Argon (Ar) ion irradiation on Fe-Al2O3 nanogranular thin film. X-ray diffraction (XRD) patterns show that the ion dose might promote the growth of the Fe2O3 phase from an amorphous phase to a crystalline phase. The magnetic and magnetoresistance properties were investigated using a vibrating sample magnetometer (VSM) and a four point probe (FPP). The results suggest that percolation concentration occurred at the 0.55 Fe volume fraction and with a maximum magnetoresistance (MR) ratio of 3%. The present MR ratio was lower than that of previous results, which might be related to the existence of the …


Digestibility Of Betung Bamboo Fiber Following Fungal Pretreatment, Widya Fatriasari, Wasrin Syafii, Nyoman J. Wistara, Khaswar Syamsu, Bambang Prasetya Aug 2014

Digestibility Of Betung Bamboo Fiber Following Fungal Pretreatment, Widya Fatriasari, Wasrin Syafii, Nyoman J. Wistara, Khaswar Syamsu, Bambang Prasetya

Makara Journal of Technology

This research evaluated the effect of fungal pretreatment of betung bamboo fibers and enzymatic- and microwaveassisted hydrolysis on the reducing sugar yield. The enzymatic hydrolysis of the pretreated biomass was carried out with cellulase and 10 and 20 FPU/g of substrate in a shaking incubator at 50 °C and 150 rpm for 48 h. The sulfuric acid concentration used in the microwave-assisted acid hydrolysis was 1.0, 2.5, and 5%, either with or without the addition of activated carbon. Microwave irradiation (330 Watt) was applied for 5–12.5 min. The yield of reducing sugar was better with the microwave-assisted acid hydrolysis, and …


Electron Emission Characteristics Of Multi-Gated Field Emitters, Hidenori Mimura, Yoichiro Neo, Toru Aoki, Tomoya Yoshida, Masayoshi Nagao Aug 2014

Electron Emission Characteristics Of Multi-Gated Field Emitters, Hidenori Mimura, Yoichiro Neo, Toru Aoki, Tomoya Yoshida, Masayoshi Nagao

Makara Journal of Technology

We have developed a multi-gated field emitter (FE) such as a quadruple-gated FE with a three-stacked electrode lens and a quintuple-gated FE with a four-stacked electrode lens. Both the FEs can focus the electron beam. However, the quintuple-gated FE has a stronger electron convergence than the quadruple-gated FE, and a beam crossover is clearly observed for the quintuple-gated FE.


Properties Of Lignin From Oil Palm Empty Fruit Bunch And Its Application For Plywood Adhesive, Lucky Risanto, Euis Hermiati, Yanni Sudiyani Aug 2014

Properties Of Lignin From Oil Palm Empty Fruit Bunch And Its Application For Plywood Adhesive, Lucky Risanto, Euis Hermiati, Yanni Sudiyani

Makara Journal of Technology

Lignin from lignocellulosic biomass is a potential biopolymer for wood adhesive. The aims of this study were to characterize lignin isolated from the black liquor of oil palm empty fruit bunch fiber pretreated with steam explosion in alkaline conditions and to examine the bond quality of aqueous polymer isocyanate (API) adhesive prepared from lignin, natural rubber latex (NRL), and polyvinyl alcohol (PVA) as base polymers with isocyanate crosslinkers. Lignin was precipitated from the black liquor by adding hydrochloric acid; then the precipitate was separated by filtration, thoroughly washed with water up to pH 2 and pH 5, and dried. The …


The Gaussian Orthogonal Laplacianfaces Modelling In Feature Space For Facial Image Recognition, Arif Muntasa Aug 2014

The Gaussian Orthogonal Laplacianfaces Modelling In Feature Space For Facial Image Recognition, Arif Muntasa

Makara Journal of Technology

Dimensionality reduction based on appearance has been interesting issue on the face image research fields. Eigenface and Fisherface are linear techniques based on full spectral features, for both Eigenface and Fisherface produce global manifold structure. Inability of them in yielding local manifold structure have been solved by Laplacianfaces and further improved by Orthogonal Laplacianfaces, so it can yield orthogonal feature vectors. However, they have also a weakness, when training set samples have non-linear distribution. To overcome this weakness, feature extraction through data mapping from input to feature space using Gaussian kernel function is proposed. To avoid singularity, the Eigenface decomposition …


Series-Interconnected Plastic Dye-Sensitized Solar Cells Prepared By Low- Temperature Binder-Free Titania Paste, Erlyta Septa Rosa, Lia Muliani, Shobih Shobih, Jojo Hidayat, Brian Yuliarto Aug 2014

Series-Interconnected Plastic Dye-Sensitized Solar Cells Prepared By Low- Temperature Binder-Free Titania Paste, Erlyta Septa Rosa, Lia Muliani, Shobih Shobih, Jojo Hidayat, Brian Yuliarto

Makara Journal of Technology

The aim of this research is to study dye-sensitized solar cells (DSSC). This was implemented on a flexible polyethylene terephthalate (PET) substrate using a mixture of transparent and scattered mesoporous anatase-titania as the electron transport layer for the photoelectrode. This mixture of anatase titania performed a dual function of light scattering and efficient dye absorption. In this study, a porous nano-TiO2 film was prepared on indium tin oxide (ITO) coated polyethylene terephthalate (PET) by using a binder-free titania paste; on it, a DSSC was fabricated. The paste which contained a mixture of TiO2 nanoparticles, acid chloride, and ethanol was printed …


Does A Plastron Improve Heat Transfer?, Madani A. Khan, Jeffrey Alston, Andrew Guenthner Aug 2014

Does A Plastron Improve Heat Transfer?, Madani A. Khan, Jeffrey Alston, Andrew Guenthner

STAR Program Research Presentations

Superamphiphobic surfaces strongly repel both water and oils. In this work, aluminum coupons are processed by sanding with various grit of sand paper to impart microscale roughness. Subsequent submersion of the aluminum substrate in boiling water grows nanoscale grass-like structures. The oxide layer of Al is slightly soluble in water. During a fast diffusion/equilibrium, Al2O3 nanograss grows on the surface. A low energy coating is then deposited on the surface. The micro and nanoscale features create re-entrant structures that trap air enabling contact liquid to be in a Cassie-Baxter state. Superamphiphobicity of the samples were confirmed by …


Investigation Of Stabilization Mechanisms For Colloidal Suspension Using Nanoparticles., Qingwen He Aug 2014

Investigation Of Stabilization Mechanisms For Colloidal Suspension Using Nanoparticles., Qingwen He

Electronic Theses and Dissertations

Over the past decade, charged nanoparticles have been found to enhance the stability of colloidal suspensions. One promising explanation of this stabilization mechanism is “Nanoparticle Haloing”- the formation of a non-adsorbing nanoparticle layer surrounding neutral colloids that would induce an effective electrostatic repulsion between them. The objective of this work was to investigate the effect of additional charged nanoparticles on the interaction between neural colloids in nanoparticle-regulated complex fluids. Firstly, colloidal probe Atomic Force Microscopy (CP-AFM) is used to directly measure the interaction force in such system with nanoparticle volume fractions varying from 10-6 to 10-2. It is found that …


High-Productivity Membrane Adsorbers: Polymer Surface-Modification Studies For Ion-Exchange And Affinity Bioseparations, Heather Chenette Aug 2014

High-Productivity Membrane Adsorbers: Polymer Surface-Modification Studies For Ion-Exchange And Affinity Bioseparations, Heather Chenette

All Dissertations

This Dissertation centers on the surface-modification of macroporous membranes to make them selective adsorbers for different proteins, and the analysis of the performance of these membranes relative to existing technology. Traditional chromatographic separations for the isolation and purification of proteins implement a column packed with resin beads or gel media that contain specific binding ligands on their exposed surface area. The productivity of this process is balanced by the effective use of the binding sites within the column and the speed at which the separation can take place, in addition to the need to maintain sufficient protein purity and bioactivity. …


Photo-Sensitivity Of Large Area Physical Vapor Deposited Mono And Bilayer Mos2, Baoming Wang, Christopher Muratore, Andrey A. Voevodin, M. Amanul Haque Aug 2014

Photo-Sensitivity Of Large Area Physical Vapor Deposited Mono And Bilayer Mos2, Baoming Wang, Christopher Muratore, Andrey A. Voevodin, M. Amanul Haque

Chemical and Materials Engineering Faculty Publications

We present photosensitivity in large area physical vapour deposited mono and bi-layer MoS2 films. Photo-voltaic effect was observed in single layer MoS2 without any apparent rectifying junctions, making device fabrication straightforward. For bi-layers, no such effect was present, suggesting strong size effect in light-matter interaction. The photo-voltaic effect was observed to highly direction dependent in the film plane, which suggests that the oblique deposition configuration plays a key role in developing the rectifying potential gradient. To the best of our knowledge, this is the first report of any large area and transfer free MoS2 photo device with performance comparable to …


Application Of Membrane Processes For Concentration And Separation Of Sugar Streams In Biofuel Production, Mohammadmahdi Malmali Aug 2014

Application Of Membrane Processes For Concentration And Separation Of Sugar Streams In Biofuel Production, Mohammadmahdi Malmali

Graduate Theses and Dissertations

The overall objective of this study was identification and development of a sugar concentration/separation membrane filtration unit to improve the bioconversion of lignocellulosic biomass into chemicals and fuels. This thesis is divided into three main parts. The first part is about our studies on the use of nanofiltration membranes for concentration of sugars in a lignocellulosic biomass hydrolysate. In addition, the feasibility of simultaneous removal of acetic acid, 5-(hydroxymethyl)furfural and furfural from the hydrolysate has also been investigated. The results obtained indicate that both concentration of sugars and removal of hydrolysis degradation products is feasible. However, careful selection of the …


Hydraulic Fracturing Water Recycle Through Optimal Ultrafiltration And Nanofiltration Membranes System Design, Long Tran Aug 2014

Hydraulic Fracturing Water Recycle Through Optimal Ultrafiltration And Nanofiltration Membranes System Design, Long Tran

Graduate Theses and Dissertations

Innovations in hydraulic fracturing technology have created opportunities for petroleum and natural gas production. This technology injects water, sand, and additives to create fissures in rock formations and discharge oil and gas to the surface. The average amount of water used per well is approximately 4.4 million gallons. The large water demand and the complexities involved in wastewater treatment make this process very expensive and not sustainable as far as water use is concerned. Flexible membrane technology has not been developed to process fracking water for re-use across the U.S. The objective of this project is to compare and analyze …


A Soft Condensed Matter Approach Towards Mathematical Modelling Of Mass Transport And Swelling In Food Grains, Michael Chapwanya, N. Misra Aug 2014

A Soft Condensed Matter Approach Towards Mathematical Modelling Of Mass Transport And Swelling In Food Grains, Michael Chapwanya, N. Misra

Articles

Soft condensed matter (SCM) physics has recently gained importance for a large class of engineering materials. The treatment of food materials from a soft matter perspective, however, is only at the surface and is gaining importance for understanding the complex phenomena and structure of foods. In this work, we present a theoretical treatment of navy beans from a SCM perspective to describe the hydration kinetics. We solve the transport equations within a porous matrix and employ the Flory–Huggin’s equation for polymer–solvent mixture to balance the osmotic pressure. The swelling of the legume seed is modelled as a moving boundary with …