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2015

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Articles 241 - 270 of 491

Full-Text Articles in Chemical Engineering

Dendrimer-Guest Interactions: Challenging Conventional Wisdom, Ryan S. Defever, Sapna Sarupria Apr 2015

Dendrimer-Guest Interactions: Challenging Conventional Wisdom, Ryan S. Defever, Sapna Sarupria

Chemical and Biomolecular Graduate Research Symposium

Solutions to many future challenges - including water purification, drug delivery, and energy storage - will require innovative new materials. Dendrimers are a class of materials with wide-ranging applications whose behavior is not fully understood. In many potential applications, dendrimers interact with small molecules. Our work focuses on describing the fundamental mechanisms governing the interactions between dendrimers and hydrocarbons using molecular modeling and computer simulations. A common view of dendrimer host-guest interactions is that the guest molecules are encapsulated in protected interior voids within the dendrimer structure. Our results present an alternative picture and show that the association of a …


Effect Of Process Variables On Mechanical And Transport Properties Of Carbon Fibers From Mesophase Pitch, Victor Bermudez, Amod Ogale Apr 2015

Effect Of Process Variables On Mechanical And Transport Properties Of Carbon Fibers From Mesophase Pitch, Victor Bermudez, Amod Ogale

Chemical and Biomolecular Graduate Research Symposium

To obtain mesophase pitch-based carbon fibers with improved mechanical strength while retaining superior electrical and thermal properties by

i) Systematic investigation of the relationship between DDR versus longitudinal and transverse microstructure of mesophase MP fibers; and

ii) Developing a novel type of microstructure


Heterogeneous Catalysis Of Aqueous Phase Reforming Of Glycerol With First Principle Calculations And Molecular Dynamics Simulations, Tianjun Xie, Rachel B. Getman Apr 2015

Heterogeneous Catalysis Of Aqueous Phase Reforming Of Glycerol With First Principle Calculations And Molecular Dynamics Simulations, Tianjun Xie, Rachel B. Getman

Chemical and Biomolecular Graduate Research Symposium

No abstract provided.


Dosi In Novel Geometry Dishes, Jonathan Lawrence Lambert Jones Apr 2015

Dosi In Novel Geometry Dishes, Jonathan Lawrence Lambert Jones

Electronic Theses and Dissertations

Effects of hemodynamic forces on cellular response are well studied. Wall shear stress is regularly accepted as the primary hemodynamic force affecting cellular response. Hemodynamic forces studies utilize Petri dishes on orbital shakers to grow cells for the experiments since this is an easily scalable system. However, characterizing the hemodynamics is difficult since the oscillatory swirling motion creates multidirectional and variable magnitude shear throughout the dish. Thus, a novel geometry dish that could create uniaxial shear with less variation in magnitude would be advantageous for studying shear stress effects on cellular response. The purpose of this thesis was to explore …


Functional Clay Nanotubes And Composites, Yafei Zhao Apr 2015

Functional Clay Nanotubes And Composites, Yafei Zhao

Doctoral Dissertations

Tubular nanomaterials and their composites have been extensively studied in recent years in the fields of physics, chemistry, biology, and biomedicine. Carbon nanotube is the most commonly studied tubular nanomaterial; however, toxicity and high cost make it less attractive in industry and thus restricts its applications. Halloysite nanotubes, which are available in abundance in the United States as well as in other countries around the world, is a low-cost, unique and versatile aluminosilicate mineral with a chemical formula of Al4Si4O10(OH)8·nH2O. Basically, the halloysite tube diameter is around 50 nm and the length varies with different locations ranging from 0.4-1.5 μm. …


Investigating A Pilot Area In The Williston Basin Three Forks Formation To Determine The Optimal Inter-Well Spacing And Hydraulic Fracture Length To Maximize Economic Recovery, Adhikeshavan Ravee Apr 2015

Investigating A Pilot Area In The Williston Basin Three Forks Formation To Determine The Optimal Inter-Well Spacing And Hydraulic Fracture Length To Maximize Economic Recovery, Adhikeshavan Ravee

Graduate Theses & Non-Theses

The objective of this work is to determine optimal inter-well spacing and hydraulic fracture length of the Three Forks assets in the Williston Basin operated by SM Energy. SM Energy is an independent exploration and production company with operations across North America, mainly in Texas and North Dakota. SM Energy recently switched to infill drilling development in their North Dakota assets and is interested in knowing the economically optimal number of wells that can be drilled per two-section drilling unit.

A simulation approach was taken in this research to address SM Energy’s issue. For research purposes a small pilot area …


Phonon-Drag Contribution To Seebeck Coefficient Of Ge-On-Insulator Substrate Fabricated By Wafer Bonding Process, Veerappan Manimuthu, Shoma Yoshida, Yuhei Suzuki, Faiz Salleh, Mukannan Arivanandhan, Yoshinari Kamakura, Yasuhiro Hayakawa, Hiroya Ikeda Apr 2015

Phonon-Drag Contribution To Seebeck Coefficient Of Ge-On-Insulator Substrate Fabricated By Wafer Bonding Process, Veerappan Manimuthu, Shoma Yoshida, Yuhei Suzuki, Faiz Salleh, Mukannan Arivanandhan, Yoshinari Kamakura, Yasuhiro Hayakawa, Hiroya Ikeda

Makara Journal of Technology

In order to build high-sensitivity infrared photodetectors using SiGe nanowires, we investigate the thermoelectric characteristics of Ge-on-insulator (GOI) layers as a reference for SiGe. We fabricate p-type GOI substrates with an impurity concentration of 1016-1018cm-3 by a wafer-bonding process using Ge and oxidized Si wafers. Annealing treatment is performed in order to further increase the bonding strength of Ge/SiO2 interface. We measure the Seebeck coefficient in the temperature range of 290-350 K. The Seebeck coefficient of the GOI layers is very close to the theoretical value for Ge, calculated on the basis of carrier transport. Hence, there is a small …


Using Mixtures Of Fatty Acid Methyl Esters As Phase Change Materials For Concrete, Leah Christine Liston Apr 2015

Using Mixtures Of Fatty Acid Methyl Esters As Phase Change Materials For Concrete, Leah Christine Liston

Open Access Theses

Phase change materials (PCMs) are an effective way of storing/releasing thermal energy via phase transformations. Incorporating PCMs into concrete pavements at airports has been suggested as a means to reduce the accumulation of snow and ice on runways. This thesis reports on the development of two phase change materials composed of binary mixtures of fatty acid methyl esters (FAME) which provide a solid-liquid transition slightly above 0°C with a high enthalpy of fusion. Current findings of this study indicate that these mixtures have the necessary properties to be a high performance PCM with the potential to reduce the levels of …


Optimal Start-Up Control Of An Evaporation System Modeled As An Interconnected Hybrid Dynamical System, Rithesh Iyer Apr 2015

Optimal Start-Up Control Of An Evaporation System Modeled As An Interconnected Hybrid Dynamical System, Rithesh Iyer

Open Access Theses

The purpose of this research is to investigate the feasibility and advantageous outcomes of modeling a complicated non-linear hybrid dynamical process as an interconnected dynamical system for the purpose of solving a hybrid optimal control problem under the framework of nonlinear model predictive control. This work considers a hybrid model of the startup process of an evaporation system. In this evaporation system a liquid containing mixture of a non-volatile component A and volatile solvents B (water) and C (alcohol) is heated to evaporate the solvents and obtain component A at a higher concentration using a column that is temperature controlled …


Effect Of Maleic Acid On The Selectivity Of Glucose And Fructose Dehydration And Degradation, Ximing Zhang Apr 2015

Effect Of Maleic Acid On The Selectivity Of Glucose And Fructose Dehydration And Degradation, Ximing Zhang

Open Access Dissertations

5-Hydroxymethyfurfural (HMF), a platform chemical can upgrade to a variety of fuels and polymers, can be manufactured from lignocellulose. This study focuses on the Lewis and Brønsted acid effect on hexose dehydration for HMF production. We report the positive effect of maleic acid, a dicarboxylic acid used as Brønsted acid, on the selectivity of hexose dehydration to 5-hydroxymethyfurfural (HMF), and subsequent hydrolysis to levulinic and formic acids. We also describe the kinetic analysis of a Lewis acid (AlCl 3) alone and in combination with HCl or maleic acid to catalyze the isomerization of glucose to fructose, dehydration of fructose …


Experimental And Modeling Investigation Of Cellulose Nanocrystals Polymer Composite Fibers, Si Chen Apr 2015

Experimental And Modeling Investigation Of Cellulose Nanocrystals Polymer Composite Fibers, Si Chen

Open Access Dissertations

Cellulose nanocrystals (CNCs) are a class of newly developed and sustainable nanomaterial derived from cellulose-based materials such as wood. There have been substantial research efforts to utilize these materials as reinforcing agents. However, in order to develop CNC nanocomposites with industrial applications, it is necessary to understand how addition of CNCs affect the properties of the polymer nanocomposite. In the present work, several approaches, experimental and theoretical, are presented in an effort to characterize and understand the effect of CNCs on the properties of polymer CNC fibers. ^ Two experimental methods were used to develop cellulose acetate (CA) and CNC …


Optimization Of Graphene-Based Materials Outperforming Host Epoxy Matrices, Liberata Guadagno, Marialuigia Raimondo, Luigi Vertuccio, Marco Mauro, Gaetano Guerra, Khalid Lafdi, Biagio De Vivo, Patrizia Lamberti, Giovanni Spinelli, Vincenzo Tucci Apr 2015

Optimization Of Graphene-Based Materials Outperforming Host Epoxy Matrices, Liberata Guadagno, Marialuigia Raimondo, Luigi Vertuccio, Marco Mauro, Gaetano Guerra, Khalid Lafdi, Biagio De Vivo, Patrizia Lamberti, Giovanni Spinelli, Vincenzo Tucci

Chemical and Materials Engineering Faculty Publications

The degree of graphite exfoliation and edge-carboxylated layers can be controlled and balanced to design lightweight materials characterized by both low electrical percolation thresholds (EPT) and improved mechanical properties. So far, this challenging task has been undoubtedly very hard to achieve.

The results presented in this paper highlight the effect of exfoliation degree and the role of edge-carboxylated graphite layers to give self-assembled structures embedded in the polymeric matrix. Graphene layers inside the matrix may serve as building blocks of complex systems that could outperform the host matrix. Improvements in electrical percolation and mechanical performance have been obtained by a …


General Method To Predict Voltage-Dependent Ionic Conduction In A Solid Electrolyte Coating On Electrodes, Jie Pan, Yang-Tse Cheng, Yue Qi Apr 2015

General Method To Predict Voltage-Dependent Ionic Conduction In A Solid Electrolyte Coating On Electrodes, Jie Pan, Yang-Tse Cheng, Yue Qi

Chemical and Materials Engineering Faculty Publications

Understanding the ionic conduction in solid electrolytes in contact with electrodes is vitally important to many applications, such as lithium ion batteries. The problem is complex because both the internal properties of the materials (e.g., electronic structure) and the characteristics of the externally contacting phases (e.g., voltage of the electrode) affect defect formation and transport. In this paper, we developed a method based on density functional theory to study the physics of defects in a solid electrolyte in equilibrium with an external environment. This method was then applied to predict the ionic conduction in lithium fluoride (LiF), in contact with …


Group Decisions In Value Management, Christiono Utomo, Farida Murti, Arazi Idrus Apr 2015

Group Decisions In Value Management, Christiono Utomo, Farida Murti, Arazi Idrus

Makara Journal of Technology

This research deals with a technique to expedite group decision making during the selection of technical solutions for value management process. Selection of a solution from a set of alternatives is facilitated by evaluating using multicriteria decision making techniques. During the process, every possible solution is rated on criteria of function and cost. Function deals more with quality than with quantity, and cost can be calculated based on the theoretical time value of money. Decision-making techniques based on satisfying games are applied to determine the relative function and cost of solutions and hence their relative value. The functions were determined …


Development Of A Rapid Compression Controlled-Expansion Machine For Chemical Ignition Studies, John Neuman Apr 2015

Development Of A Rapid Compression Controlled-Expansion Machine For Chemical Ignition Studies, John Neuman

Master's Theses (2009 -)

The ability to accurately model fuel combustion processes is essential to the development of transportation, power generation, and manufacturing technology. Models describing the kinetics of chemical oxidation are readily available and highly refined for a wide range of test fuels. However, these models still suffer from high levels of uncertainty under engine-relevant conditions, largely due to a lack of consistency between published validation data. An experimental testing apparatus, known as the Rapid Compression Controlled-Expansion Machine (RCCEM) has been designed and fabricated to conduct chemical kinetic studies. The RCCEM features a pneumatically-driven, custom-designed cam, which governs the volumetric compression and expansion …


Fiber Optic Ring Resonator Sensor Detection Technique Based On Spectral Intensity Integration, Purnomo Sidi Priambodo, Sasono Rahardjo, Gunawan Witjaksono, Djoko Hartanto Apr 2015

Fiber Optic Ring Resonator Sensor Detection Technique Based On Spectral Intensity Integration, Purnomo Sidi Priambodo, Sasono Rahardjo, Gunawan Witjaksono, Djoko Hartanto

Makara Journal of Technology

Resonant field phenomenon in optical ring resonator has been a major theme for various studies and can be used for various sensor applications. The spectral response shape changes are subjects to be discussed and analyzed for detection in optical sensor system. The spectral response changes are caused by various factors ranging from refractive index of the surrounding medium, medium loss due to absorption and scattering, and coupling variation between waveguides. These optical phenomena are mostly used for bio-sensor applications, since it is free from electromagnetic interference (EMI) and non-physically destructive. In this paper, we discuss our current research in developing …


Seebeck Coefficient Of Soi Layer Induced By Phonon Transport, Faiz Salleh, Takuro Oda, Yuhei Suzuki, Yoshinari Kamakura, Hiroya Ikeda Apr 2015

Seebeck Coefficient Of Soi Layer Induced By Phonon Transport, Faiz Salleh, Takuro Oda, Yuhei Suzuki, Yoshinari Kamakura, Hiroya Ikeda

Makara Journal of Technology

The Seebeck coefficient of a patterned Si wire on P-doped SOI (Si-on-insulator) layer with a carrier concentration of 1018 cm-3 was measured near room temperature. The Seebeck coefficient is found to be smaller than that in the SOI layer and to be closer to the calculated Seebeck coefficient including the electronic contribution. The decrease in the Seebeck coefficient of Si wire is likely to occur due to the elimination of the contribution of phonon drag part. From the theoretical calculation of scattering rates by considering the scattering processes in phonon system, it is considered that an increase in phonon-boundary scattering …


Nebulized Solvent Ablation Of Aligned Plla Fibers For The Study Of Neurite Response To Anisotropic-To-Isotropic Fiber/Film Transition (Afft) Boundaries In Astrocyte-Neuron Co-Cultures, Jonathan M. Zuidema, Gregory P. Desmond, Christopher J. Rivet, Kathryn R. Kearns, Deanna M. Thompson, Ryan J. Gilbert Apr 2015

Nebulized Solvent Ablation Of Aligned Plla Fibers For The Study Of Neurite Response To Anisotropic-To-Isotropic Fiber/Film Transition (Afft) Boundaries In Astrocyte-Neuron Co-Cultures, Jonathan M. Zuidema, Gregory P. Desmond, Christopher J. Rivet, Kathryn R. Kearns, Deanna M. Thompson, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Developing robust invitro models of in vivo environments has the potential to reduce costs and bring new therapies from the bench top to the clinic more efficiently. This study aimed to develop a biomaterial platform capable of modeling isotropic-to-anisotropic cellular transitions observed in vivo, specifically focusing on changes in cellular organization following spinal cord injury. In order to accomplish this goal, nebulized solvent patterning of aligned, electro spun poly-. l-lactic acid (PLLA) fiber substrates were developed. This method produced a clear topographic transitional boundary between aligned PLLA fibers and an isotropic PLLA film region. Astrocytes were then seeded on these …


Optimization Of A Combined Approach For The Treatment Of Desalination Reject Brine And Capture Of Co₂, Ameera Fares Mohammad Apr 2015

Optimization Of A Combined Approach For The Treatment Of Desalination Reject Brine And Capture Of Co₂, Ameera Fares Mohammad

Theses

Carbon dioxide (CO₂) is the most widespread greenhouse gas that traps heat and raises the global temperature, contributing to climate change. Existing techniques to sequester carbon dioxide have numerous environmental concerns and usually require an extensive amount of energy. New technologies and methods, such as reactions with desalination reject brine according to the Solvay process, offer new hope for the reduction of carbon dioxide concentration in the atmosphere. Brine management is another environmental concern, as many desalination plants need to find suitable approaches for the treatment or disposal of the large amounts of concentrated brine, resulting from the desalination processes. …


Correlating Petrophysical Calculations From Density Logs To Production Trends In The Elm Coulee Field, Montana, Colton Mall Apr 2015

Correlating Petrophysical Calculations From Density Logs To Production Trends In The Elm Coulee Field, Montana, Colton Mall

Graduate Theses & Non-Theses

This thesis investigates correlations between estimated upper Bakken total organic carbon (TOC) and production data in the Elm Coulee field, and tests two hypotheses for defining simulation model properties with the results. The purpose of this research is to investigate potential correlations between upper Bakken TOC and production and exploit any correlations to develop better methods for defining simulation model properties. This may reduce time necessary to history match production from an Elm Coulee model and help to explain the production variability. The study area is in Montana townships 24N-57E, 23N-57E, and 24N-55E. Public domain completion and production data for …


Characterization Of Plasticizer-Polymer Coatings For The Detection Of Benzene In Water Using Sh-Saw Devices, Jude Coompson Apr 2015

Characterization Of Plasticizer-Polymer Coatings For The Detection Of Benzene In Water Using Sh-Saw Devices, Jude Coompson

Master's Theses (2009 -)

Benzene is a constituent component of crude oil that has been classified as a carcinogen by the EPA with a maximum contamination level (MCL) of 5ppb in drinking water. However, of the aromatic compounds, benzene has one of the lowest polymer-water partition coefficients using commercially available polymers as sensor coatings, resulting in poor limits of detection. This work investigates new coating materials based on polymer/plasticizer mixtures coated onto a shear horizontal surface acoustic wave (SH-SAW) sensor to detect benzene in water. There are many polymers which are unavailable for use as a sensing polymer due to their glassy nature. The …


Hazard-Driven Drivers’ Behaviours Towards Vehicle-To-Median Safe Distances, Martha Leni Siregar Apr 2015

Hazard-Driven Drivers’ Behaviours Towards Vehicle-To-Median Safe Distances, Martha Leni Siregar

Makara Journal of Technology

A median is required for a two-way road to separate traffic from opposing lanes and to prevent head-on collisions. However, studies indicate that medians are also perceived as hazards which need to be avoided during driving. This hazard perception is manifested in drivers’ changing behavior towards various types of medians along the driving lanes inform of their tendency to allow various safe distances to the medians. The Indonesian Highway Capacity Manual (IHCM) does not differentiate between types of medians and the influence on the drivers’ choice of safe margin to the medians. Therefore, this study looks into how the existence …


Construction Of A Novel Method Of Measuring Thermal Conductivity For Nanostructures, Hiroya Ikeda, Shoma Yoshida, Yuhei Suzuki, Veerappan Manimuthu, Faiz Salleh, Fujio Kuwahara, Masaru Shimomura, Kenji Murakami Apr 2015

Construction Of A Novel Method Of Measuring Thermal Conductivity For Nanostructures, Hiroya Ikeda, Shoma Yoshida, Yuhei Suzuki, Veerappan Manimuthu, Faiz Salleh, Fujio Kuwahara, Masaru Shimomura, Kenji Murakami

Makara Journal of Technology

With the aim of characterizing the thermal conduction in a nanometer-scaled materials, we have constructed a novel method on the basis of an ac calorimetric method. In this method, periodic sample heating is performed by light irradiation and the corresponding periodic temperature is detected by infrared irradiative thermometer. This makes us measure the thermal diffusivity out of contact with the objective sample. In the present study, we confirm to measure the thermal diffusivity of bulk Si and Cu by this non-contact method with halogen-lamp irradiation. In determining the thermal diffusivity from the relationship between distance deviation and delay time, the …


The Effects Of The Types Of Milk (Cow, Goat, Soya) And Enzymes (Rennet, Papain, Bromelain) Toward Cheddar Cheese Production, Ariestya Arlene, Anastasia Prima Kristijarti, Ivana Ardelia Apr 2015

The Effects Of The Types Of Milk (Cow, Goat, Soya) And Enzymes (Rennet, Papain, Bromelain) Toward Cheddar Cheese Production, Ariestya Arlene, Anastasia Prima Kristijarti, Ivana Ardelia

Makara Journal of Technology

The objectives of this research are to study the effects of different types of milk and enzymes toward the yield and quality (moisture, ash, protein, fat content, and texture) of cheddar cheese and the interaction between those two variables during the process. The types of milk are cow, goat, and soya milk, while the types of enzymes are rennet, papain, and bromelain enzymes. Regarding the procedure, the milk is first pasteurized before CaCl2 and Lactobacillus lactis that acts as the acidifier starter as much as 0.2% (w/v) and 0.5% of the milk volume are added respectively. The amount of enzyme …


Energy And Exergy Analysis Of Kalina Cycle For The Utilization Of Waste Heat In Brine Water For Indonesian Geothermal Field, Nasruddin Nasruddin, Agus Noor Sidiq, Abdulmajeed Mohamad, Rama Usvika Apr 2015

Energy And Exergy Analysis Of Kalina Cycle For The Utilization Of Waste Heat In Brine Water For Indonesian Geothermal Field, Nasruddin Nasruddin, Agus Noor Sidiq, Abdulmajeed Mohamad, Rama Usvika

Makara Journal of Technology

The utilization of waste heat in a power plant system—which would otherwise be released back to the environment—in order to produce additional power increases the efficiency of the system itself. The purpose of this study is to present an energy and exergy analysis of Kalina Cycle System (KCS) 11, which is proposed to be utilized to generate additional electric power from the waste heat contained in geothermal brine water available in the Lahendong Geothermal power plant site in North Sulawesi, Indonesia. A modeling application on energy and exergy system is used to study the design of thermal system which uses …


Insights Into Ultrasonic Release From Eliposomes, Marjan Javadi, William G. Pitt Mar 2015

Insights Into Ultrasonic Release From Eliposomes, Marjan Javadi, William G. Pitt

Faculty Publications

A novel nanosized liposomal carrier was prepared consisting of perfluorocarbon emulsion droplet(s) encapsulated inside a liposome, which is called an eLiposome. This 200-nm construct is useful for acoustically activated drug delivery because ultrasound causes the emulsion droplet to expand from liquid to gas, which expansion ruptures the eLiposome bilayer and releases the internal contents. This study focuses on the parameters that influence control of the release of calcein (a model drug), including ultrasound amplitude, insonation time, and perfluorocarbon vapor pressure as a function of temperature and composition. The results show that calcein release increases as the ultrasound amplitude or insonation …


Microfracture And Surfactant Impact On Linear Cocurrent Brine Imbibition In Gas-Saturated Shale, Yongpeng Sun, Baojun Bai, Mingzhen Wei Mar 2015

Microfracture And Surfactant Impact On Linear Cocurrent Brine Imbibition In Gas-Saturated Shale, Yongpeng Sun, Baojun Bai, Mingzhen Wei

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

During and after hydraulic fracturing, fluid-shale interaction has a prominent impact on liquid retention and thus on gas phase permeability and gas productivity. By providing a low surface tension or wettability alteration, surfactants are widely used to decrease liquid retention after fracturing. To evaluate the liquid intake of a rock sample, an imbibition experiment is commonly used, especially when it is treated by a surfactant. However, conventional imbibition experiments with gas shale could not quantitate the imbibition behaviors as it does with conventional rocks because of the low porosity and extremely low permeability of gas shale. In this paper, a …


Effects Of Magnetic Nanoparticles And External Magnetostatic Field On The Bulk Heterojunction Polymer Solar Cells, Kai Wang, Chao Yi, Chang Liu, Xiaowen Hu, Steven Chuang, Xiong Gong Mar 2015

Effects Of Magnetic Nanoparticles And External Magnetostatic Field On The Bulk Heterojunction Polymer Solar Cells, Kai Wang, Chao Yi, Chang Liu, Xiaowen Hu, Steven Chuang, Xiong Gong

Polymer Science Faculty Research

The price of energy to separate tightly bound electron-hole pair (or charge-transfer state) and extract freely movable charges from low-mobility materials represents fundamental losses for many low-cost photovoltaic devices. In bulk heterojunction (BHJ) polymer solar cells (PSCs), approximately 50% of the total efficiency lost among all energy loss pathways is due to the photogenerated charge carrier recombination within PSCs and low charge carrier mobility of disordered organic materials. To address these issues, we introduce magnetic nanoparticles (MNPs) and orientate these MNPS within BHJ composite by an external magnetostatic field. Over 50% enhanced efficiency was observed from BHJ PSCs incorporated with …


Composition And Work Function Relationship In Os–Ru–W Ternary Alloys, Phillip D. Swartzentruber, Michael J. Detisch, Thomas John Balk Mar 2015

Composition And Work Function Relationship In Os–Ru–W Ternary Alloys, Phillip D. Swartzentruber, Michael J. Detisch, Thomas John Balk

Chemical and Materials Engineering Faculty Publications

Os–Ru thin films with varying concentrations of W were sputter deposited in order to investigate their structure–property relationships. The films were analyzed with x-ray diffraction to investigate their crystal structures, and a Kelvin probe to investigate their work functions. An Os–Ru–W film with ∼30 at. % W yielded a work function maximum of approximately 5.38 eV. These results align well with other studies that found work function minima from thermionic emission data on M-type cathodes with varying amounts of W in the coatings. Furthermore, the results are consistent with other work explaining energy-level alignment and charge transfer of molecules on …


The Effect Of Microstructure On Transport Properties Of Porous Electrodes, Serena Wen Peterson Mar 2015

The Effect Of Microstructure On Transport Properties Of Porous Electrodes, Serena Wen Peterson

Theses and Dissertations

The goal of this work is to further understand the relationships between porous electrode microstructure and mass transport properties. This understanding allows us to predict and improve cell performance from fundamental principles. The investigated battery systems are the widely used rechargeable Li-ion battery and the non-rechargeable alkaline battery. This work includes three main contributions in the battery field listed below.

Direct Measurement of Effective Electronic Transport in Porous Li-ion Electrodes. An accurate assessment of the electronic conductivity of electrodes is necessary for understanding and optimizing battery performance. The bulk electronic conductivity of porous LiCoO2-based cathodes was measured as a …