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A General Approach Towards The Synthesis Of Amido-Functionalized Biodegradable Polyesters, Joseph Russell 2010 Bucknell University

A General Approach Towards The Synthesis Of Amido-Functionalized Biodegradable Polyesters, Joseph Russell

Master’s Theses

The thesis presented here describes methodologies to produce pendant group functionalized polyesters from amido-functionalized α-hydroxy acids. The synthetic methods used to produce the functionalized α-hydroxy acids are compatible with a wide array of functional groups, making this technique highly versatile. The synthesis of functionalized polyesters was investigated to develop polymers with properties that may improve the capabilities of existing biodegradable polyesters for applications in controlled release pharmaceuticals. Chemically modified a-hydroxy acids were synthesized by reacting glyoxylic acid with a primary or secondary amide. To demonstrate the utility of this reaction, fourstructurally dissimilar amide substituents were examined including 2-pyrrolidione, benzamide, acetamide …


A Microfluidic Method To Measure Diffusion In Hydrogels, Andrew Lee Litzenberger 2010 Bucknell University

A Microfluidic Method To Measure Diffusion In Hydrogels, Andrew Lee Litzenberger

Master’s Theses

A novel microfluidic method is proposed for studying diffusion of small molecules in a hydrogel. Microfluidic devices were prepared with semi-permeable microchannels defined by crosslinked poly(ethylene glycol) (PEG). Uptake of dye molecules from aqueous solutions flowing through the microchannels was observedoptically and diffusion of the dye into the hydrogel was quantified. To complement the diffusion measurements from the microfluidic studies, nuclear magnetic resonance(NMR) characterization of the diffusion of dye in the PEG hydrogels was performed. The diffusion of small molecules in a hydrogel is relevant to applications such asdrug delivery and modeling transport for tissue-engineering applications. The diffusion of small …


Application Of An Efficient Nonconventional Heterogeneous Catalyst For Biodiesel Synthesis From Pongamia Pinnata Oil, Y. C. Sharma, Bhaskar Singh, John Korstad 2010 Banaras Hindu University

Application Of An Efficient Nonconventional Heterogeneous Catalyst For Biodiesel Synthesis From Pongamia Pinnata Oil, Y. C. Sharma, Bhaskar Singh, John Korstad

College of Science and Engineering Faculty Research and Scholarship

Recycled chicken eggshells after calcination have been used as a nonconventional heterogeneous catalyst for biodiesel synthesis from karanja oil from the pongam tree (Pongamia pinnata). The catalyst was characterized on X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and differential thermal analysis/thermogravimetric analysis (DTA/TGA). The formation of the calcium oxide phase was confirmed at 900°C after calcination. A high biodiesel yield of 95.0% and conversion of 97.4% was obtained at an 8:1 (alcohol/oil) molar ratio, 2.5 wt%catalyst, and 2.5 h reaction time at 65±°0.5C. The biodiesel conversion was determined by Fourier transform nuclear magnetic resonance (FTNMR) spectroscopy.


High Yield And Conversion Of Biodiesel From A Nonedible Feedstock (Pongamia Pinnata), Yogesh C. Sharma, Bhaskar Singh, John Korstad 2010 Banaras Hindu University

High Yield And Conversion Of Biodiesel From A Nonedible Feedstock (Pongamia Pinnata), Yogesh C. Sharma, Bhaskar Singh, John Korstad

College of Science and Engineering Faculty Research and Scholarship

An efficient approach has been adopted for the synthesis of biodiesel developed from karanja, a nonedible oil feedstock. A two-step reaction was followed for synthesis of biodiesel. Karanja oil possessing a high free fatty acid content was esterified with sulfuric acid, and the product obtained was further converted to fatty acid alkyl esters (biodiesel) by transesterification reactions. A moderate molar ratio of 6:1 (methanol/oil) was efficient for acid esterification with 1.5% v/v H2SO4 and 1 h of reaction time at 60 ± 0.5 °C, which resulted in reduction of FFA from 19.88 to 1.86 mg of KOH/g. …


Rotational Relaxation Times Of Individual Compounds With Simulations Of Molecular Asphalt Models, Liqun Zhang, Michael L. Greenfield 2010 University of Rhode Island

Rotational Relaxation Times Of Individual Compounds With Simulations Of Molecular Asphalt Models, Liqun Zhang, Michael L. Greenfield

Chemical Engineering Faculty Publications

The dynamical properties of a complex system incorporate contributions from the diverse components from which it is constituted. To study this relationship in a multicomponent system, relaxation times based on rotation autocorrelation functions in molecular dynamics simulations were analyzed for molecules in two sets of unmodified and polymer-modified model asphalt/bitumen systems over 298–473 K. The model asphalt systems were proposed previously to approximate the chemical and mechanical properties of real asphalts. Relaxations were modeled using a modified Kaulrausch–Williams–Watts function and were based on the third Legendre polynomial of normal vector time correlation functions for aromatic species asphaltene, polar aromatic, naphthene …


X-Ray Absorption Spectroscopy Applied To Mixed-Metal Iron-Based Fischer-Tropsch Catalysts, Andrew Allen Campos 2010 Louisiana State University and Agricultural and Mechanical College

X-Ray Absorption Spectroscopy Applied To Mixed-Metal Iron-Based Fischer-Tropsch Catalysts, Andrew Allen Campos

LSU Doctoral Dissertations

Synthetic fuels derived from methane, coal or biomass are essential in addressing future transportation fuel demands which are expected to exceed petroleum-derived capacities. The Fischer-Tropsch synthesis (FTS) is the most studied technique for the conversion of coal or biomass-derived syngas into transportation fuels. Fe-based catalysts are typically used for the FTS of biomass and/or coal-derived syngas due to: the relatively low cost of iron, water-gas shift activity, and low methane selectivity at industrial FTS conditions. Fe/Cu/SiO2 Fischer-Tropsch catalysts promoted with Cr, Mn, Mo, W, or Zr were studied in-situ, using Fe K-edge TPR XANES (temperature programmed reduction X-ray absorption near-edge …


Remote Controlled Hydrogel Nanocomposites: Synthesis, Characterization, And Applications, Nitin S. Satarkar 2010 University of Kentucky

Remote Controlled Hydrogel Nanocomposites: Synthesis, Characterization, And Applications, Nitin S. Satarkar

University of Kentucky Doctoral Dissertations

There is significant interest in the development of hydrogels and hydrogel nanocomposites for a variety of biomedical applications including drug delivery, sensors and actuators, and hyperthermia cancer treatment. The incorporation of nanoparticulates into a hydrogel matrix can result in unique material characteristics such as enhanced mechanical properties, swelling response, and capability of remote controlled (RC) actuation. In this dissertation, the development of hydrogel nanocomposites containing magnetic nanoparticles/carbon nanotubes, actuation with remote stimulus, and some of their applications are highlighted.

The primary hydrogel nanocomposite systems were synthesized by incorporation of magnetic nanoparticles into temperature responsive N-isopropylacrylamide (NIPAAm) matrices. Various nanocomposite properties …


Targeted Polymeric Biomaterials For The Prevention Of Post Surgical Adhesions, John M. Medley 2010 University of Kentucky

Targeted Polymeric Biomaterials For The Prevention Of Post Surgical Adhesions, John M. Medley

University of Kentucky Doctoral Dissertations

Despite recent advances in surgical technique and the development of numerous therapeutic agents, the formation post surgical adhesions (PSA) continues to cause complications for many patients. In this research, we have employed a rational system to develop a novel treatment to address this clinical need. Based on an understanding of the biochemical events that lead to PSA formation, a series of targeted polymeric biomaterials was designed to interrupt the fibrin gel matrix propagation and suppress PSA formation.

Using group transfer polymerization, a series of well controlled block copolymers of polyacrylic acid and poly(ethylene glycol-methacrylate) based materials was synthesized. Subsequent functionalization …


The Functionalization Of Single Wall Carbon Nanotubes For Bioapplications, Pu Zhang 2010 Missouri University of Science and Technology

The Functionalization Of Single Wall Carbon Nanotubes For Bioapplications, Pu Zhang

Doctoral Dissertations

"In the past few years, the functionalization of carbon nanotubes has received considerable attention due to their extraordinary mechanical, electrical, optical and thermal properties. Using single wall carbon nanotube as a platform in bioanalytical and biomedical applications has also been extensively studied. This dissertation consists of four papers. In the first paper, various methods to functionalize single wall carbon nanotubes with immobilized enzyme for bioanalytical application were investigated. It was found that the covalent functionalization method was not an ideal methodology for enzyme addition neither in terms of enzyme loading amount nor activity retention compared to other methods. Use of …


Identifying Multiple Steady States In The Design Of Reactive Distillation Processes, Thomas Karl Mills 2010 Missouri University of Science and Technology

Identifying Multiple Steady States In The Design Of Reactive Distillation Processes, Thomas Karl Mills

Doctoral Dissertations

"Global homotopy continuation is used to identify multiple steady states in ideal reactive flash and reactive distillation systems involving a reaction of the form A+B [symbol for <--> C taking place in the liquid phase. The choice of specifications has an influence on the existence of multiple solutions for both the flash and the column. For the flash, specification of the heat input or withdrawal can give rise to multiplicities while specification of the split fraction does not. Specification of one internal energy balance variable and one external material balance variable does not produce multiplicities in the column; however, specification of …


Desulfurization And Tar Removal From Gasifier Effluents Using Mixed Rare Earth Oxides, Sumana Adusumilli 2010 Louisiana State University and Agricultural and Mechanical College

Desulfurization And Tar Removal From Gasifier Effluents Using Mixed Rare Earth Oxides, Sumana Adusumilli

LSU Master's Theses

Biomass gasification is a promising source of fuels. However, hydrogen sulphide, tars and other by-products must be removed from the raw gas because they deactivate downstream reforming and water gas shift catalysts. The goal of this project is to find the best REO combination for simultaneous tar cracking and desulfurization of gasifier effluents and to find the sorbents that are stable at high operating temperatures of gasifiers. Simultaneous tar cracking and H2S removal from a simulated gasifier effluent was tested using different rare earth mixed oxide (REO) catalysts/sorbents based on Ce/LaOx, Ce/La/MOx and Ce/La/M2Ox/Al2O3 where M is a transition metal …


Integrating Bioprocesses Into Industrial Complexes For Sustainable Development, Debalina Sengupta 2010 Louisiana State University and Agricultural and Mechanical College

Integrating Bioprocesses Into Industrial Complexes For Sustainable Development, Debalina Sengupta

LSU Doctoral Dissertations

The objective of this research is to propose, develop and demonstrate a methodology for the optimal integration of bioprocesses in an existing chemical production complex. Chemical complex optimization is determining the optimal configuration of chemical plants in a superstructure of possible plants based on economic, environmental and sustainable criteria objective function (triple bottomline) and solves a mixed integer non linear programming problem. This research demonstrated the transition of production of chemicals from non-renewable to renewable feedstock. A conceptual design of biochemical processes was converted to five industrial scale designs in Aspen HYSYS® process simulator. Fourteen input-output block models were created …


Supercritical Carbon Dioxide Processing Of Nano - Clays And Polymer/Clay Nanocomposites, Mihai Manitiu 2010 Wayne State University

Supercritical Carbon Dioxide Processing Of Nano - Clays And Polymer/Clay Nanocomposites, Mihai Manitiu

Wayne State University Dissertations

Effective dispersion of the fillers in a polymer matrix and improvement of polymer-clay interactions are two key challenges in the field of nanocomposites. A novel processing method that utilizes the unique properties of supercritical carbon dioxide (scCO2) to disperse nano-clay and prepare a series of polymer/clay nanocomposites with enhanced properties was explored.

Significant dispersion was achieved using the scCO2 process with Cloisite 10A without the presence of an organic phase as evident by the absence of the diffraction peak in WAXD and the presence of individual tactoids that lost their parallel registry. The expanded flexible structure of the scCO2 processed …


Design Of A Polysaccharide Derived Tissue Engineered Vascular Graft, Irina Robu 2010 Wayne State University

Design Of A Polysaccharide Derived Tissue Engineered Vascular Graft, Irina Robu

Wayne State University Dissertations

DESIGN OF A POLYSACCHARIDE DERIVED TISSUE ENGINEERED VASCULAR GRAFT

By

Irina Robu

November 2010

Advisor: Dr. Howard Matthew

Major: Chemical Engineering

Degree: Doctor of Philosophy

As the most frequent congenital anomaly and the leading cause of death, congenital heart disease is an attractive target for tissue engineering research. The challenging target to engineer a native blood vessel stems from the need to find substitutes for pediatric patients born with congenital defects. The tissue engineering graft functions to bring various cells of the vasculature in close proximity to one another to enable intercellular signaling which facilitates cell adhesion, migration and differentiation. …


Molecular Modeling Of Energetic Materials And Chemical Warfare Agents, Nandhini Sokkalingam 2010 Wayne State University

Molecular Modeling Of Energetic Materials And Chemical Warfare Agents, Nandhini Sokkalingam

Wayne State University Dissertations

Contamination of military sites by energetic materials and chemical warfare agents is a growing problem. To avoid health hazards associated with these compounds, it is necessary to decontaminate or remediate the contaminated sites. Effective decontamination requires knowledge of environmental fate of contaminants and the appropriate remediation methodologies. While the fate of chemical warfare agents are well studied, the impact of certain energetic materials in the environment is relatively unknown. So the current focus is determining environmental fate of Insensitive Munitions (IM) which are energetic materials that have low shock sensitivity and high thermal stability and developing detection schemes for identifying …


A Simulation Study Of Factors That Affect Pressure Control During Kick Circulation In Managed Pressure Drilling Operations, Jose Eduardo Eduardo Chirinos 2010 Louisiana State University and Agricultural and Mechanical College

A Simulation Study Of Factors That Affect Pressure Control During Kick Circulation In Managed Pressure Drilling Operations, Jose Eduardo Eduardo Chirinos

LSU Master's Theses

An university-industry consortium has been studying alternative well control procedures to be used for kicks taken during managed pressure drilling (MPD) operations using the constant bottom hole pressure (CBHP) method. The CBHP method of MPD allows more precise control of wellbore pressure than conventional drilling. MPD surface equipment allows more alternatives for controlling a kick and may support faster detection of kicks and losses which can reduce the severity of a well control event. Nevertheless, the elimination of well control incidents cannot be guaranteed, and the uncertainty in downhole drilling margins are not reduced by adopting MPD methods. The primary …


Enhanced Vacuum Drying Through Improved Solvent Recovery, Reduced Process Cycle Times And Prediction Of Drying Duration, Diana Patricia Mesa Delgado 2010 Department of Chemical and Process Engineering, Cork Institute of Technology, Cork, Ireland.

Enhanced Vacuum Drying Through Improved Solvent Recovery, Reduced Process Cycle Times And Prediction Of Drying Duration, Diana Patricia Mesa Delgado

Theses

Drying of pharmaceuticals and fine chemicals is often accomplished under vacuum conditions to enhance energy efficiency and to avoid overheating of thermo sensitive materials. This project aims to study vacuum drying operations to obtain a better understanding of this process so as to optimize drying performance. This project obtained industrial data collected from a range companies in Ireland.

Pharmaceutical companies started assessing processes and making changes to drying processes from 2004 onwards; these initiatives are due to economic pressures, environmental issues and the Process Analytical Technology (PAT) initiative launched by the FDA in 2004.

Vacuum drying has been used in …


Enhanced Pervaporation Using A Novel Pump Configuration, Donough Patrick Shanahan 2010 Department of Chemical and Process Engineering, Cork Institute of Technology, Cork, Ireland.

Enhanced Pervaporation Using A Novel Pump Configuration, Donough Patrick Shanahan

Theses

The pervaporation process is investigated in this work under the guises of process design improvements and process performance. Several avenues of research were investigated.

The main aim of the project was to investigate the use of liquid ring vacuum pumps for permeate recovery at laboratory and industrial scales. Due to technical and economical issues, these pumps were deemed unsuitable. This analysis then had to be extended further. Previous work investigated the use of dry vacuum pump systems on a lab scale and this work was extended to industrial scale simulations. Results from the lab scale process particularly those relating to …


An Experimental Study Of Surfactant Enhanced Waterflooding, Paulina Metili Mwangi 2010 Louisiana State University and Agricultural and Mechanical College

An Experimental Study Of Surfactant Enhanced Waterflooding, Paulina Metili Mwangi

LSU Master's Theses

Surfactants have a variety of applications in the petroleum industry due to their remarkable ability to lower the oil-water interfacial tension and alter wettability. However, surfactant adsorption on rock surfaces has severely crippled this means of improving oil recovery due to the high cost associated with the large quantities of surfactant needed. A previous experimental study by Ayirala (2002) reported the development of mixed wettability using a nonionic surfactant. At this mixed-wet state he was able to recover about 94% of the original oil in place. The underlying motivation of this study was to achieve such high recoveries without using …


Supercritical Pyrolysis Of N-Decane, Sean Bagley 2010 Louisiana State University and Agricultural and Mechanical College

Supercritical Pyrolysis Of N-Decane, Sean Bagley

LSU Doctoral Dissertations

Fuels used in future generations of high-speed jet aircraft will be required to take on increasing heat loads in their role as the primary coolant for the absorption of waste heat from the engine. As a consequence, the hydrocarbon fuels will be exposed to elevated temperatures and pressures prior to their use as fuels, conditions which are beyond the critical point of the fuel and which lead to the formation of carbonaceous solid deposits in the pre-combustion environment.

Deposition of solids causes reduced engine performance and eventual failure, so understanding the mechanisms by which thermally stressed hydrocarbons become solids is …


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