Other Chemical Engineering Commons^™

Elucidating The Properties And Mechanism For Cellulose Dissolution In Tetrabutylphosphonium-Based Ionic Liquids Using High Concentrations Of Water, Brad Crawford

Graduate Theses, Dissertations, and Problem Reports (ETD)

The structural, transport, and thermodynamic properties related to cellulose dissolution by tetrabutylphosphonium chloride (TBPCl) and tetrabutylphosphonium hydroxide (TBPH)-water mixtures have been calculated via molecular dynamics simulations. For both ionic liquid (IL)-water solutions, water veins begin to form between the TBPs interlocking arms at 80 mol % water, opening a pathway for the diffusion of the anions, cations, and water. The water veins allow for a diffusion regime shift in the concentration region from 80 to 92.5 mol % water, providing a higher probability of solvent interaction with the dissolving cellulose strand. The hydrogen bonding was compared between small and large …

Assessing Magnetic Iron Oxide Nanoparticles Properties Under Different Thermal Treatments, Erick S. Vasquez, Evan M. Prehn, Keisha B. Walters

Chemical and Materials Engineering Faculty Publications

Magnetic nanoparticle structures have been examined as potential carrier vehicles and substrates in a wide range of applications where they undergo mechanical, chemical and/or thermal manipulation to allow for their modification, conjugation and transport. For safe and effective use, it is imperative to not only measure the initial physicochemical and structural properties of nanomaterials, but also identify and quantify any property changes related to a loss of chemical and/or physical integrity during processing and usage conditions. In this study an assessment of iron oxide magnetic nanoparticle thermal stability using modulated differential scanning calorimetry (mDSC) and a controlled-heating system is conducted …

Non-Invasive Detection And Assessment Of Coronary Stenosis From Blood Mean Residence Times., Javad Hashemi

Electronic Theses and Dissertations

Coronary artery stenosis is an abnormal narrowing of a coronary artery caused by an atherosclerotic lesion that reduces lumen space. Fractional flow reserve (FFR) is the gold standard method to determine the severity of coronary stenosis based on the determination of rest and hyperemic pressure fields, but requires an invasive medical procedure. Normal FFR is 1.0 and FFR RT, to account for varying volume and flow rate of individual segments. Blood_RT was computed in 100 patients who had undergone the pressure-wire FFR procedure, and a threshold for Blood_RT was determined to assess the physiological significance of a stenosis, …

Stabilization Of Bimodal Colloidal Systems Via Nanoparticle Haloing In Microgravity., Luke Hawtrey

Electronic Theses and Dissertations

Colloidal suspensions typically contain a multi-phase system of solid particles suspended in a liquid medium. Colloids are widely used in industrial applications such as inks, paints, motor oils, foods, cosmetics, and many more. Colloidal systems are typically formed by the interaction of the attractive van der Waals forces and one or more repulsive forces. These repulsive forces include electrostatic repulsion, steric hindrance, and nanoparticle haloing. Nanoparticle Haloing (NPH) is a phenomenon discovered in 2001 as a viable method to stabilize colloidal systems of uncharged silica microparticles using highly charged zirconia nanoparticles. For this thesis the effects of NPH were tested …

Breaking Coastal Hypoxia: Destratification Of Gulf Of Mexico Deadzone To Encourage Oxygen Transport Downwards To Maintain Marine Fauna, Veda Thipparthi

LSU Master's Theses

As a consequence of seasonal eutrophication and human input, a vast hypoxic area termed The Dead Zone develops every year in the Gulf of Mexico (GOM) during summer along the Louisiana coastline characterized by vertical seawater density-stratification with oxygen concentrations less than 2 mg.l^-1 at the seafloor. It poses a threat to bottom-dwelling faunae and their environment which has negative ecological and economic consequences. This project aims to mitigate hypoxia by employing mechanical impellers placed at strategic water depths and locations in the Gulf. Enhanced transport of oxygen results by mixing oxygen-enriched seawater at the surface, downward into the …

The Effects Of Temperature On The Yields Of Aliphatic And Aromatic Products From The Supercritical Pyrolysis Of 1-Octene, Elizabeth Anne Hurst

LSU Doctoral Dissertations

Prior to their combustion, fuels for future high-speed aircraft are expected to experience supercritical conditions, leading to the production of polycyclic aromatic hydrocarbons (PAH), precursors to solid carbonaceous deposits, via pyrolytic reactions. These solid deposits can clog fuel-transfer lines, causing unsafe aircraft operation. To prevent the formation of fuel-line deposits, it is critical to understand the reaction pathways that lead to PAH formation in the supercritical fuel pyrolysis environment.

To better understand the role of large 1-alkenes in PAH formation, supercritical pyrolysis experiments with model fuel 1-octene, a representative 1-alkene product from supercritical n-alkane pyrolysis, have been performed. The …

Extraction-Photometric Determination Of Bismuth (Iii) With 1-(2-Pyridylaze)-2-Naphthol, Turabdjanov Sadritdin, Otakuzieva Vazira, Giyasov Anvar, Rakhmatullaeva Nargiza

CHEMISTRY AND CHEMICAL ENGINEERING

The conditions of selective extraction of the bismuth (III) by inert organic solvents in the presence of DMFA are established. The conditions for complex formation of the bismuth (III) with the PAN directly in the organic phase are found. It is possible to increase the sensitivity of the methodology using more sensitive azoreagents that have not found the application in practice due to their low selectivity. The effect of extraneous ions on the results of the definition of the bismuth (III) with the PAN azoreagent is investigated. In the presence of large amounts of extraneous ions the determination of bismuth …

Analysis Of Experimental Research In Determining Bubbling Extractor Mixing Zones’ Sizes, Karimov Ikromali

CHEMISTRY AND CHEMICAL ENGINEERING

In the inner mixing zone of the tested suspended extractor, the fluid and gas flows in the stream and the external mixing zone moves in a contradictory flow. In order for these mixing zones to operate equally in hydrodynamic mode, their gas values should be equal. This is achieved by the correct selection of the dimensions of the mixing zones of the liquid and gas. The article summarizes the results of the study of the measurement of the mixing zones of the apparatus.

Study Of Amino-Acid Composition Of Seed Of Oats Fruit (Avena Sativa L.), Nurullaeva Dilobar, Farmanova Nodira

CHEMISTRY AND CHEMICAL ENGINEERING

For the first time, the amino acid composition of the seed oat fruit harvested in the Republic of Uzbekistan was stud-ied. Chromatographic detection of amino acids was performed by the method of ascending one-dimensional paper chroma-tography; violet, red-violet and yellow staining was observed, indicating the presence of free amino acids in the raw materi-al under study. The determination of the qualitative and quantitative content of amino acids of oat fruit was carried out by high performance liquid chromatography (HPLC) on an Agilent Technologies 1200 chromatograph, column 75x4.6 mm Discovery HS C18. Qualitative analysis and quantitative calculation of the concentration of …

Research Of Physical And Chemical Indicators And Food Value Of Semi-Finished Products Of Sauce-Past Of Fruits And Vegetables, Atakhanov Shukhrat, Dadamirzaev Muzaffar, Akramboev Rasuljon, Otakhanov Shokirjon

CHEMISTRY AND CHEMICAL ENGINEERING

Development of technology for the storage and processing of fruits and vegetables and an increase in the degree of consumption of pro-cessed products among the population is an urgent problem of the present time.Developed recipes for semi-finished sauce-pastes, consisting of fruits, vegetables and their mixtures, the technology of their production. These recipes rationally used sesame of Yerusalem artichoke - secondary raw materials of the canning industry, the powder of the peel of Walnuts, sunflower seeds. Used existing methods for the determination of physical-chemical parameters and nutritional value of semi-finished sauce-paste. A recipe and production technology for a semi-finished product, persim-mon …

Extraction Of The Cotton Cake By The Influence Of Pulse Electric Field, Kayimov Fazliddin, Mazhidov Qahramon

CHEMISTRY AND CHEMICAL ENGINEERING

The technology of extraction of cotton cake by the influence of a pulsed electric field on the extracted mass is researched. The dependence of the specific conductivity on the inverse temperature using the influence of a pulsed electric field has been estab-lished. The technological process of extraction of vegetable oil is accelerated and an increase in oil yield is ensured.

Optothermal Microbubble Assisted Manufacturing Of Nanogap-Rich Structures For Active Chemical Sensing, Farzia Karim, Erick S. Vasquez, Yvonne Sun, Chenglong Zhao

Chemical and Materials Engineering Faculty Publications

Guiding analytes to the sensing area is an indispensable step in a sensing system. Most of the sensing systems apply a passive sensing method, which waits for the analytes to diffuse towards the sensor. However, passive sensing methods limit the detection of analytes to a picomolar range on micro/nanosensors for a practical time scale. Therefore, active sensing methods need to be used to improve the detection limit in which the analytes are forced to concentrate on the sensors. In this article, we have demonstrated the manufacturing of nanogap-rich structures for active chemical sensing. Nanogap-rich structures are manufactured from metallic nanoparticles …

Optimization And Structural Stability Of Gold Nanoparticle–Antibody Bioconjugates, Robert T. Busch, Farzia Karim, John Weis, Yvonne Sun, Chenglong Zhao

Chemical and Materials Engineering Faculty Publications

Gold nanoparticles (AuNPs) bound with biomolecules have emerged as suitable biosensors exploiting unique surface chemistries and optical properties. Many efforts have focused on antibody bioconjugation to AuNPs resulting in a sensitive bioconjugate to detect specific types of bacteria. Unfortunately, bacteria thrive under various harsh environments, and an understanding of bioconjugate stability is needed. Here, we show a method for optimizing Listeria monocytogenes polyclonal antibodies bioconjugation mechanisms to AuNPs via covalent binding at different pH values, from 2 to 11, and 2-(N-morpholino)ethanesulfonic acid (MES), 3-(N-morpholino)propanesulfonic acid, NaOH, HCl conditions. By fitting Lorentz curves to the amide I and II regions, we …

Recycling Of The Mixture Resulted From Sanitary Ware Waste, Roller Kiln Waste And Ceramic Tiles Sludge Waste In The Manufacturing Of Ceramic Floor Tiles, Mai H. Roushdy

Chemical Engineering

Ceramic tiles industry is a big source for wastes that have a bad effect on the environment. The first source of waste is associated with roller kilns as it needs a periodic surface grinding to its rollers which results in a waste powder. The second type of waste is ceramic tiles sludge which produced from a water treatment plant. The third waste is sanitary ware waste which coming out from sanitary ware industry. The main aim of this paper is to investigate the ability of substituting part of the main body mixture of floor tiles by these three types of …

Computational And Experimental Approach To Understanding The Structural Interplay Of Self-Assembled End-Terminated Alkanethiolates On Gold Surfaces, Juganta K. Roy, Erick S. Vasquez, Henry P. Pinto, Swati Kumari, Keisha B. Walters, Jerzy Leszcynski

Chemical and Materials Engineering Faculty Publications

Applications of self-assembled monolayers (SAMs) on surfaces are prevalent in modern technologies and drives the need for a better understanding of the surface domain architecture of SAMs. To explore structural interaction at the interface between gold surfaces and a hydroxyl-terminated alkanethiol, 11-hydroxy-1-undecanethiol, (C11TH) we have employed a combined computational and experimental approach. Density functional theory (DFT) calculations were carried out on the thiol–gold interface using both the Perdew–Burke–Ernzerhof (PBE) and van der Waals (optB86b) density functionals. Our ab initio molecular dynamics (AIMD) simulations revealed that the interface consists of four different distinguished phases, each with different C11TH orientations. Experiments involved …

Fabrication Of Polyvinylidene Fluoride Hollow Fiber Membranes For Membrane Distillation, Abdullah Al Balushi

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Desalination technologies can help humanity tap into the most abundant source of water on earth, seawater; however, desalination is an energy-demanding process. Most of the desalination plants worldwide use conventional energy resources; therefore, desalination leaves a large carbon footprint. Solar energy is an available source of energy that can be harvested and integrated into desalination systems.

Membrane distillation (MD) is an emerging purification technology that many offers many advantages over traditional desalination systems. For starters, it can utilize low-grade thermal energy to drive the separation, therefore, it can be suitably integrated into the solar-thermal energy scheme. Additionally, MD can be …

Development Of A Methodology For Characterizing Reaction Kinetics, Rheology, And In-Situ Compaction Of Polyimide Prepregs During Cure, James Raymond Magato, Donald A. Klosterman

Chemical and Materials Engineering Faculty Publications

PMR-type polyimide prepregs are challenging to fabricate into high quality composites due to volatiles that are generated and must be removed in situ during processing. The current work was conducted to develop accurate, reliable, and practical characterization techniques of the prepreg rheology, volatile generation, and subsequent volatile removal from the prepreg during composite fabrication. Thermal analysis was used to characterize volatile generation, reaction rates, and rheology. A novel approach was used to measure the thickness of the prepreg in situ during vacuum bag/oven processing using a high-temperature LVDT. Experimental results are presented for the commercially available RM-1100 polyimide/carbon prepreg system, …

Recycling Of The Mixture Resulted From Roller Kiln Waste And Ceramic Tiles Sludge Waste In The Manufacturing Of Ceramic Floor Tiles, Mai H. Roushdy

Chemical Engineering

Ceramic tiles industry produced many types of wastes that are routinely discarded as stock piles. One of the environmental problems associated with roller kilns is the periodic need to grind its rollers which results in a waste powder. The second type of waste is ceramic tiles sludge which produced from a water treatment plant in the ceramic tiles factory. This paper investigates the probability of substituting part of the main body of floor tiles mixture by these two types of waste powder. Many Experiments were done on the raw materials. Rectangular tile specimens were molded, dried and fired. Linear firing …

Group Iv Environmentally Benign, Inexpensive Semiconductor Nanomaterials For Solar Cells, Lisa Je

ENGS 86 Independent Projects (AB Students)

Modern solar cells are composed of silicon, cadmium tellurium, and copper indium gallium diselenide. While these materials are efficient, elements such as cadmium and indium are rare and expensive. To make this renewable energy source more inexpensive and sustainable, the Liu Optics lab is substituting expensive rare earth metals for more commonly found transition state metals. Work has been done to replace the solar cell layers composed of cadmium and gallium to replace them with glass, silicon, and/or thin films. Common metals such as germanium and tin are investigated and characterized to provide a platform for solar cell components.

The Use Of Electrical Resistance Tomography To Determine The Minimum Agitation Speed For Solids Suspension In Stirred Tank Reactors, Baran Teoman

Theses

Njs, the minimum agitation speed needed to just suspend all the solid particles in a solid-liquid mixture stirred in an agitated vessel, is a critical parameter to properly operate industrial tanks in a large number of industrial operations. As a result, a significant literature on Njs is available. The oldest and the most common method to measure Njs experimentally is that of Zwietering’s (Chem. Eng. Sci., 1958, 8, 244-253), where Njs can be visually obtained by determining when the solids stay at the bottom of the tank for no more than 1-2 seconds before being swept away. Although this has …