Molecular Dynamics Simulation Of The Structure, Dynamics And Crystallization Of Ionic Liquids Under Confinement And Low Temperature,
2015
Louisiana State University and Agricultural and Mechanical College
Molecular Dynamics Simulation Of The Structure, Dynamics And Crystallization Of Ionic Liquids Under Confinement And Low Temperature, Xiaoxia He
LSU Doctoral Dissertations
Ionic liquids (ILs) have sparked widespread interest due to their peculiar properties and the resulting possibility of manifold applications. In this dissertation, molecular dynamics (MD) simulations have been used to elucidate the dynamics, structure and crystallization of ionic liquids in the bulk and confinement. First we studied the properties of the ILs [dmim+][Cl-] and [emim+][NTf2-] when they are confined inside nanomaterials such as CMK-3, CMK-5 and an isolated amorphous carbon nanopipe (ACNP). The results indicate that the ions of the ILs form different layers inside these nanomaterials and their dynamics are slower due to the confinement. We also found significant …
A Model-Based Framework To Control The Crystal Size Distribution,
2015
Louisiana State University and Agricultural and Mechanical College
A Model-Based Framework To Control The Crystal Size Distribution, Navid Ghadipasha
LSU Master's Theses
Crystallization is an old unit operation in the industry which is widely used as a separation process due to its ability to produce highly valued chemical with high purity. Despite the long history of batch crystallization, industry still relies on rule of- thumb techniques for their crystallization processes. Thus, any method to improve the products characteristics such as size and morphology will be highly valued. Advances in robustness and accuracy of automated in situ sensors give the possibility to move towards an engineering based approach by implementing the real-time monitoring and control of the process. The research undertaken here investigates …
Aqueous Atmospheric Species, A Dual Study: 1. Comparison Of The Effects Of Temperature, Oxygen Level, Ionic Strength, And Ph On The Reaction Of Benzene With Hydroxyl Radicals At The Air-Water Interface To The Bulk Aqueous Phase. 2. Determination Of Carbonyl Compounds In Fog Water Samples Via Online Concentration And Hplc,
2015
Louisiana State University and Agricultural and Mechanical College
Aqueous Atmospheric Species, A Dual Study: 1. Comparison Of The Effects Of Temperature, Oxygen Level, Ionic Strength, And Ph On The Reaction Of Benzene With Hydroxyl Radicals At The Air-Water Interface To The Bulk Aqueous Phase. 2. Determination Of Carbonyl Compounds In Fog Water Samples Via Online Concentration And Hplc, Aubrey Anne Heath
LSU Doctoral Dissertations
The air-water interface is the largest interface in the environment. Atmospheric droplets, such as fog, which can have an exceptionally high surface area-to-volume ratio, also have a large range of physical and chemical properties (e.g. temperature, pH, ionic strength, and chemical composition) based on location, time of day, and emission source. Unlike larger atmospheric droplets, which are predominately characterized by bulk aqueous phase conditions, reactions that take place in fog droplets are determined by both the bulk-aqueous phase and the air-water interface due to a high surface area-to-volume ratio. In order to have a greater understanding of atmospheric processes and …
Application Of Discrete Element Method And Computational Fluid Dynamics To Selected Dispersed Phase Flow Problems,
2015
Louisiana State University and Agricultural and Mechanical College
Application Of Discrete Element Method And Computational Fluid Dynamics To Selected Dispersed Phase Flow Problems, Oladapo Olanrewaju Ayeni
LSU Doctoral Dissertations
A parallel discrete particle modelling framework (PAR_DPM3D) is applied to study three fundamental multiphase flow problems: The sedimentation of a cluster of particles in a viscous ambient fluid, multiphase flow in a bench-scale fluidized bed and granular segregation and mixing dynamics in a rotating drum. Various phenomena including torus formation and particle cluster breakup are reproduced. We provide new insights into the volume fraction dependence of the dynamic characteristics of a settling particle cluster and find a similar dependence in the simulations as in the theoretical predictions of Nitsche and Batchelor 1. Similarities in the interaction between a system of …
Laboratory Experimental Demonstration Of The Effect Of Oceanic Whitecaps In The Transport Of Oil And Dispersant Components To The Atmosphere,
2015
Louisiana State University and Agricultural and Mechanical College
Laboratory Experimental Demonstration Of The Effect Of Oceanic Whitecaps In The Transport Of Oil And Dispersant Components To The Atmosphere, Paria Avij
LSU Doctoral Dissertations
During the DWH oil spill, vast quantities of crude oil were released into the sea-surface environment of the Gulf of Mexico. There has been ample research focused on the transport of oil into the different environmental sections. Evaporation has been considered to be the only transport pathway of oil spill matter into the atmosphere. However, the aerosolization of oil and dispersant via bursting bubbles as they occur in whitecaps and breaking waves has not been considered in the oil and dispersant budget calculation. This transport vector is significant as it is the dominant source of particulate matter production in the …
A Fast Approach For Preparation Of Adsorbent From Reed Black Liquor And Its Performance In Equilibrium And Kinetic Gas Separation,
2015
Edith Cowan University
A Fast Approach For Preparation Of Adsorbent From Reed Black Liquor And Its Performance In Equilibrium And Kinetic Gas Separation, G. Yang, Yong Sun, C. Wen, J. Zhang
Research outputs 2014 to 2021
A new approach using reed pulping black liquor by hydrothermal reaction followed by fast carbonization at 350 °C in fluidized bed reactor for 5 minutes was proposed in this paper. The BET specific surface area generated at optimum conditions reached 390 m2 g–1. The CO2 selectivity over CH4 and N2 comparable to commercial activated carbons was obtained. The isosteric enthalpies of adsorption for CO2, CH4 and N2 on the resultant carbon sample prepared at optimum conditions show surface heterogeneity. The kinetic results indicate its potential for separation of carbon dioxide from carbon dioxide/methane mixture.
Insights From A Global Engineering Outreach Course,
2014
Brigham Young University - Provo
Insights From A Global Engineering Outreach Course, Randy S. Lewis
Faculty Publications
A two-semester multi-disciplinary Global Engineering Outreach (GEO) course was initiated in 2007 to provide an opportunity for junior and senior-level engineering and technology students to design and implement humanitarian-based engineering projects in developing communities. Recently, the course was integrated with a sociology course to enhance the educational opportunities between social scientists and engineers. During the GEO course, students work on small-scale projects that are selected in conjunction with members of the developing communities. Students regularly interact with community members during project development. Following the GEO course, students participate in a two-week implementation trip. Learning outcomes associated with the course are …
Platinum Hollow Nanospheres With Different Sizes: Controllable Synthesis And Electrocatalytic Oxidation Toward Methanol,
2014
College of Chemistry and Chemical Engineering, Jiangxi Normal University, Nanchang 330022, China;
Platinum Hollow Nanospheres With Different Sizes: Controllable Synthesis And Electrocatalytic Oxidation Toward Methanol, Xuan Lin, Mei-Qin Cheng, Zhong-Jin Shang, Ting Xiong, Xian-Tu Zhang, Wei Tian, Jian-Yun Lin, Qi-Ling Zhong, Bin Ren
Journal of Electrochemistry
The selenium (Se) templates and hollow platinum (Pthollow) nanospheres with different sizes were controllably synthesized by adjusting the concentration of sodium dodecyl sulphonate (SDSN) (CSDSN, μmol·L-1) which was used as a surfactant. Accordingly, the Pthollow nanospheres modified glassy carbon (GC) electrode (Pthollow/GC) was prepared. The morphology and composition of Pthollow nanospheres were characterized by scanning electron microscopy (SEM), transmission electron microscope (TEM), energy dispersive X-ray spectroscopy (EDX), high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED) and X-ray diffraction (XRD) techniques. The electrocatalytic activities of Pthollow/GC and electrodeposited Pt nanoparticles modified glassy carbon electrode (Ptnano/GC) toward methanol oxidation …
Comparison In Factors Affecting Electrochemical Properties Of Thermal-Reduced Graphene Oxide For Supercapacitors,
2014
School of Material Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, China;Laboratory of Clean Energy Chemistry and Materials, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China;
Comparison In Factors Affecting Electrochemical Properties Of Thermal-Reduced Graphene Oxide For Supercapacitors, Peng Xiao, Da-Hui Wang, Jun-Wei Lang
Journal of Electrochemistry
In this paper, thermal-reduced graphene oxide (T-RGO) materials are synthesized by modified Hummer’s method, followed by thermal reduction under argon atmosphere at different temperatures. Electrochemical investigations show that, for T-RGO electrodes, good electrical conductivity is necessary and the surface functional groups play more significant role than the specific surface area in determining the electrochemical capacitance. The T-RGO obtained at 900 °C (T-RGO900) with a relatively high Brunauer-Emmett-Teller (BET) surface area (314 m2·g-1) and a high electrical conductivity (2421 S·m-1) shows a low specific capacitance of 56 F·g-1. In comparison, the T-RGO obtained …
Synthesis Of Namnpo4 By Spraying Drying-High Temperature Sintering And Its Electrochemical Performance,
2014
Xiamen University
Synthesis Of Namnpo4 By Spraying Drying-High Temperature Sintering And Its Electrochemical Performance, Xiao-Chen Lin, Xiao-Biao Wu, Xu Hou, Yong Yang
Journal of Electrochemistry
As a cathode material for sodium ion batteries, NaMnPO4/C nanocomposite is successfully synthesized by the combination of spraying drying and high temperature sintering methods. The crystal structure of the as-synthesized phosphate material is confirmed as the natrophilite NaMnPO4, which possesses orthorhombic symmetry and Pmnb space group. It is shown that the precursors are hollow spherical particles and the obtained product consists of micro-scaled secondary particles, which are composed of NaMnPO4 nanocrystallites (tens of nanometres) and amorphous carbon networks. The ionic and electronic conductivities of NaMnPO4 are both effectively enhanced with the help of this …
One-Step Synthesis Of Pani/Nihcf Hybrid Film Using Unipolar Pulse Electrodeposition And Its Electrocatalytic Reduction Performance For H2O2 Detection,
2014
College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, China;
One-Step Synthesis Of Pani/Nihcf Hybrid Film Using Unipolar Pulse Electrodeposition And Its Electrocatalytic Reduction Performance For H2O2 Detection, Sen-Liang Liao, Xiu-Min Li, Xiao-Gang Hao, Yan-Hong Wang, Chun-Feng Xue, Yong-Hong Wang
Journal of Electrochemistry
Organic–inorganic hybrid films composed of polyaniline/nickel hexacyanoferrate (PANI/NiHCF) were fabricated on platinum substrates using unipolar pulse one-step electrodeposition. The deposition mechanism of hybrid film was proposed: Due to high potential of unipolar pulse electrodeposition, which avoided the reduction of Fe(CN)63-, the films with high electrocatalytic property and “insoluble” form of NiHCF were achieved. The morphology and composition of PANI/NiHCF hybrid film were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and Fourier transform infrared spectroscopy (FT-IR). The effect of pulse potential on the electrochemical performance of hybrid film was investigated in detail. Results showed that …
Direct Electrochemistry And Glucose Biosensing Of Glucose Oxidase-Gold Nanoparticles Composite Synthesized By Enzyme Method,
2014
Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China;
Direct Electrochemistry And Glucose Biosensing Of Glucose Oxidase-Gold Nanoparticles Composite Synthesized By Enzyme Method, Fang He, Xiao-Li Qin, Ying-Chun Fu, Chao Chen, Qing-Ji Xie, Shou-Zhuo Yao
Journal of Electrochemistry
Glucose oxidase (GOx)-gold nanoparticles (AuNPs) composite was synthesized by the one-pot enzyme reaction in the mixture solution of NaAuCl4, GOx and glucose, and a Nafion/GOx-AuNPs/glassy carbon electrode was fabricated by the cast-coating method to examine the direct electrochemistry of GOx and the biosensing performance on this electrode. Such a GOx-AuNPs composite showed good direct-electrochemistry activity and bioactivity of GOx, probably because the enzyme-mediated AuNPs are close to the redox active centers of GOx. This enzyme electrode exhibited a linear amperometric response to glucose concentration (0.54 mmol·L-1) at -0.4 V (vs. SCE), and a detection limit of …
Interfacial Polymerization For Colorimetric Labeling Of Protein Expression In Cells,
2014
University of Kentucky
Interfacial Polymerization For Colorimetric Labeling Of Protein Expression In Cells, Jacob L. Lilly, Phillip R. Sheldon, Liv J. Hoversten, Gabriela Romero, Vivek Balasubramaniam, Brad J. Berron
Chemical and Materials Engineering Faculty Publications
Determining the location of rare proteins in cells typically requires the use of on-sample amplification. Antibody based recognition and enzymatic amplification is used to produce large amounts of visible label at the site of protein expression, but these techniques suffer from the presence of nonspecific reactivity in the biological sample and from poor spatial control over the label. Polymerization based amplification is a recently developed alternative means of creating an on-sample amplification for fluorescence applications, while not suffering from endogenous labels or loss of signal localization. This manuscript builds upon polymerization based amplification by developing a stable, archivable, and colorimetric …
Quantifying Individual Losses In A Direct Methanol Fuel Cell,
2014
University of South Carolina - Columbia
Quantifying Individual Losses In A Direct Methanol Fuel Cell, Jennifer Rae Ruffing
Theses and Dissertations
The performance of a direct methanol fuel cell (DMFC) is complicated due to the complex interactions of kinetic and transport processes. As a result, changes in one aspect of the cell have consequences in other aspects, which are difficult to elucidate from the full-cell polarization (i.e. voltage vs. current) behavior that fuel cell researchers often use to characterize the performance of their systems. The objective of this work was to develop a strategy to use current and voltage relationships from anode half cells, cathode half-cells, and a hydrogen pump, coupled with methanol crossover data and a mathematical model, to quantify …
Novel Biofabrication Technologies To Recapitulate In Vivo Geometries In Collagen Hydrogels,
2014
University of South Carolina - Columbia
Novel Biofabrication Technologies To Recapitulate In Vivo Geometries In Collagen Hydrogels, Veronica Rodriguez-Rivera
Theses and Dissertations
Tissue engineering and regenerative medicine aims to restore form and function to tissues that have been lost or damaged due to disease, congenital defect, or trauma. Biomaterials suitable to restore these complex tissues need to provide a balance between chemical and mechanical properties, providing accurate cell-matrix interaction and induce in vivo behaviors such as proliferation, differentiation and migration. It also requires that physical and chemical cues be presented to the body in the proper temporal and spatial pattern. The extracellular matrix exerts forces that are transmitted through focal adhesion causing changes in the cell behavior. The hypothesis for this dissertation …
Surface Modification Of Nanoplatelets In Polymer Nanocomposites,
2014
University of South Carolina - Columbia
Surface Modification Of Nanoplatelets In Polymer Nanocomposites, Shailesh K. Shori
Theses and Dissertations
In polymer nanocomposites (PNCs), it is very important that the nanofiller (typically an inorganic) is well-dispersed in an organic polymer matrix. Optimal compatibility results in end-use products such as packaging materials with enhanced properties. In practice, however, this is challenging to achieve because “ideal” dispersions require the complete uniform separation, termed exfoliation, of the nanofiller within the matrix. As a result, different nanofillers including calcium niobate (CN) and montmorillonite (MMT) are first studied for their ability to exfoliate in aqueous suspensions by measuring the organic cation uptake. The cation exchange capacity, or CEC, determined that CN needs further work before …
Theoretical Investigation Of The Catalytic, Liquid-Phase Hydrodeoxygenation Of Organic Acids And Esters,
2014
University of South Carolina - Columbia
Theoretical Investigation Of The Catalytic, Liquid-Phase Hydrodeoxygenation Of Organic Acids And Esters, Sina Behtash
Theses and Dissertations
With worldwide fossil fuel resources dwindling and greenhouse gas emissions rising, it is urgent to find renewable liquid fuel alternatives from e.g. biomass to meet the world’s growing energy demand. Lipid feedstocks and pyrolysis oils from woody biomass can be utilized for the production of second-generation biofuels via a catalytic hydrodeoxygenation (HDO) process. The conversion of fatty acids and esters plays an important role in the activity and selectivity of these processes. Understanding the HDO reaction mechanism of organic acids and esters on metal surfaces is a prerequisite for the rational design of new HDO catalysts specifically designed for upgrading …
Synthesis Of Au And Ag Catalysts With Controlled Sizes Of Metal Particles,
2014
University of South Carolina - Columbia
Synthesis Of Au And Ag Catalysts With Controlled Sizes Of Metal Particles, Eleni A. Kyriakidou
Theses and Dissertations
The performance of supported metal catalysts largely depends on the structure and composition of the metal particles and the nature of the support. In order to achieve better control over these parameters, synthetic route based on the use of templating agents has been proposed. Among the different templating agents, poly(amidoamine) (PAMAM) dendrimers have attracted a lot of recent attention as nanoparticle stabilizers. In this thesis, Au/G4OH nanocomposites were synthesized in aqueous solutions and used as precursors for the preparation of SiO2-supported Au nanoparticles. Elemental analysis, UV-Vis, and STEM measurements were used to estimate the extent of the Au-dendrimer interactions and …
A Three-Dimensional-Engineered Matrix To Study The Microenvironment Of Cancer Stem Cells,
2014
University of South Carolina - Columbia
A Three-Dimensional-Engineered Matrix To Study The Microenvironment Of Cancer Stem Cells, Samaneh Kamali Sarvestani
Theses and Dissertations
Maintenance of cancer stem cells (CSCs) is regulated by their microenvironment. As cancer cells are affected by many factors in their microenvironment, a major challenge is to isolate the effect of a specific factor on CSCs while keeping other factors unchanged. We developed a synthetic inert 3D Poly Ethylene Glycol Di-Acrylate (PEGDA) gel culture system as a unique tool to study the effect of microenvironmental factors on CSCs response. Synthetic hydrogels provide the flexibility to design three-dimensional (3D) matrices to isolate and study individual factors in the tumor microenvironment. The first objective of this work was to investigate the effect …
Bio-Active Degradable Micellar Hydrogels For Osteogenic Differentiation Of Mesenchymal Stem Cells,
2014
University of South Carolina - Columbia
Bio-Active Degradable Micellar Hydrogels For Osteogenic Differentiation Of Mesenchymal Stem Cells, Seyedsina Moeinzadeh
Theses and Dissertations
A feasible approach to the restoration of injured bone tissue is the use of tissue engineering strategies to deliver mesenchymal stem cells (MSCs) to the site of regenration in degradable, in-situ gelling, bio-active hydrogels. Although inert Polyethylene glycol (PEG) hydrogels provide flexibility in controlling the cell microenvironment, their use for in vivo applications in tissue regeneration is limited by their persistence (nondegradability) in the site of regeneration. In an attempt to produce inert hydrolytically degradable matrices for encapsulation of MSCs, hydrogels based on star PEG macromonomers chain-extended with short hydroxy acid (HA) segments (SPEXA) were synthesized and characterized with respect …
