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Articles 1 - 30 of 372
Full-Text Articles in Engineering
Novel Composite Membrane(Pes/Clay/Zeolite) For Ammonium And Sulfide Ions Removal From Sour Water, Marwa Abdel Fattah, Marwa S. Shalaby, Moustapha S. Mansour, Ahmed Badr Eldin, Ibrahim Ismail Ibrahim, Heba Abdallah
Novel Composite Membrane(Pes/Clay/Zeolite) For Ammonium And Sulfide Ions Removal From Sour Water, Marwa Abdel Fattah, Marwa S. Shalaby, Moustapha S. Mansour, Ahmed Badr Eldin, Ibrahim Ismail Ibrahim, Heba Abdallah
Mansoura Engineering Journal
The viability of human life depends heavily on the accessibility of clean water, not only for personal use but also to support various industrial, agricultural, and industrialrelated activities. Composite membranes were prepared using polyethersulfone (PES) with zeolite and clay. The membranes were fully characterized. Membrane performances were tested using sodium sulfide with a concentration of 0.365 g/l and ammonium chloride with a concentration of 0.148 g/l to study the effect of prepared composite membranes on the treatment of sour water. The membrane's mechanical properties were tested and M3 has the greatest tensile strength of 64 MPa with an elongation of …
Reaction Pathways, Kinetic Modelling And Parameter Estimation Of Heterogeneous Catalytic Trans-Esterificationprocess, Owolabi,R. U, Aderinsola A. P
Reaction Pathways, Kinetic Modelling And Parameter Estimation Of Heterogeneous Catalytic Trans-Esterificationprocess, Owolabi,R. U, Aderinsola A. P
Mansoura Engineering Journal
The kinetics of heterogeneous catalyzed trans-esterification between castor oil and methanol was studied and modeled. Kinetic data was obtained from a perfectly mixed slurry batch reactor. The modeling was conducted via the modified-hattori mechanism to determine the exact rate controlling step for the reaction. A total of five rate expressions were formed, which were as a result of; methanol adsorption, Triglyceride adsorption, Formation of the complex, Surface reaction and Glycerol desorption. Evaluation of best fitting model and parameter estimation was done using the nealder simplex least square optimization algorithm with the aid MATLAB software. The result from the regression analysis …
Effects Of Power Stations Emissions On Air Quality In Kuwait, Abdullah F.M. Al-Rukaibi, I. G. Rashed, M.M. El-Halwany, O. Hamed
Effects Of Power Stations Emissions On Air Quality In Kuwait, Abdullah F.M. Al-Rukaibi, I. G. Rashed, M.M. El-Halwany, O. Hamed
Mansoura Engineering Journal
The research describes the Gaussian plume model used to estimate the concentration of pollutants emitted from power plants and dispersed in the atmosphere. The object of the research is to compare the air quality between areas which is near to source station and away from the source station. The research estimates the concentrations of pollutants released from six electric power stations in Kuwait using the Gaussian plume model. A power plant with a stack height of 100 m, stack diameter of 2 m, and an emission rate of 1 kg/s for each station is considered. The Pasquill-Gifford stability categories are …
Economic Feasibility Of A Methanol To Dimethyl Ether Production Process To Avoid Contract Failure Shortfalls From The Covid-19 Pandemic, Jacob Noll, Robert Wasson, Harrison Mckinnis
Economic Feasibility Of A Methanol To Dimethyl Ether Production Process To Avoid Contract Failure Shortfalls From The Covid-19 Pandemic, Jacob Noll, Robert Wasson, Harrison Mckinnis
Honors Theses
Our team entered the 2021 AVEVA Academic Competition, where teams of undergraduate senior chemical engineering students competed across the country. The competition was composed of two parts: the base case design and the optimization of a chemical process. As part of the competition, our team is acting as the Engineering team for a fictional company that has given us this project. Due to COVID-19, our methanol producing company has lost a contract with a customer, leaving 23,000 tonnes/yr of unclaimed methanol. We have two choices with this methanol: either sell the methanol on the market at the spot price for …
Detection Of Nucleotides In Hydrated Ssdna Via 2-D H-Bn Nanopore With Ionic-Liquid/Salt-Water Interface, Jungsoo Lee
Detection Of Nucleotides In Hydrated Ssdna Via 2-D H-Bn Nanopore With Ionic-Liquid/Salt-Water Interface, Jungsoo Lee
Multidisciplinary Studies Theses and Dissertations
Accomplishing slow translocation speed with high sensitivity has been the greatest mission for solid-state nanopore (SSN) to electrically detect nucleobases in single-stranded DNA (ssDNA). In this study, a method to detect nucleobases in ssDNA using a SSN is introduced by considerably slowing down the translocation speed and effectively increasing its sensitivity. The ultra-thin titanium dioxide (TiO2) coated hexagonal boron nitride (h-BN) nanopore was fabricated, along with an ionic-liquid [bmim][PF6]/2.0 M KCl aqueous (cis/trans) interfacial system, to increase both the spatial and the temporal resolutions. As the ssDNA molecules entered the nanopore, a …
Engineering Dopant Position In Structure-Controlled Ceo2-Zro2 Catalysts, Behnam Safavinia
Engineering Dopant Position In Structure-Controlled Ceo2-Zro2 Catalysts, Behnam Safavinia
LSU Master's Theses
CeO2-ZrO2 (CZO) nanoparticles (NPs) have application in many catalytic reactions, such as methane reformation, due to their oxygen cycling ability. Ni doping has been shown to improve the catalytic activity and acts as an active site for the decomposition of methane. In this work, Ni:CZO NPs were synthesized via a two-step co-precipitation/molten salt synthesis to compare Ni distribution, oxygen vacancy concentration, and catalytic activity relative to a reference state-of-the-art catalyst. To better understand the effects of Ni position and dispersion, and oxygen vacancy formation in these materials, the Ni concentration, reaction time, and deposition methods were varied. …
Che 472-Hm2: Process And Plant Design Honors, Nellone Reid
Che 472-Hm2: Process And Plant Design Honors, Nellone Reid
Chemical and Materials Engineering Syllabi
No abstract provided.
Stabilization Of Β-Cristobalite In The Sio2-Alpo4-Bpo4 System, Kathryn Doyle
Stabilization Of Β-Cristobalite In The Sio2-Alpo4-Bpo4 System, Kathryn Doyle
Browse all Theses and Dissertations
Fused silica (silica glass) is transparent in the optical and near-infrared and has a low dielectric constant, making it suitable as a window material for radio frequency radiation. However, at high temperatures (>1100C), fused silica will easily creep and lose dimensional stability. Crystallized silica is much more creep resistant than fused silica. Silica crystallizes to many different structures including quartz, tridymite, and α- and β cristobalite. The only cubic polymorph, which is suitable for both optical and radio frequency transmission in polycrystalline form, is β -cristobalite. Unfortunately, this polymorph transforms to α-cristobalite at ~300C, and the volume change during …
Catalytic Waste Gasification: Water-Gas Shift & Selectivity Of Oxidation For Polyethylene, Mason J. Lang
Catalytic Waste Gasification: Water-Gas Shift & Selectivity Of Oxidation For Polyethylene, Mason J. Lang
ETD Archive
As landfills approach capacity and take up valuable land space, metropolitan areas have realized the need for waste disposal alternatives. Thus, there has been a widespread use of waste incinerators in Europe and the United States [1]; [2]. Although newer technology has made incinerators more efficient, there is an increasing interest in formulating `greener’ alternatives to incinerators. Gasification converts organic and carbonaceous materials into a combination of gaseous products known as “syngas,” or synthetic gas. This process greatly reduces the amount of hazardous emissions. The syngas produced by gasifiers has a wide range of uses, including their conversion into diesel, …
Adsorption Induced Solid Phase Transition Of Mil-53(Al), Rushik G. Bandodkar
Adsorption Induced Solid Phase Transition Of Mil-53(Al), Rushik G. Bandodkar
ETD Archive
Metal organic frameworks (MOFs) are nano-porous solids with potential applications in a wide range of fields including gas separation and catalysis. A number of metal organic frameworks show structural transformation and exceptional flexibility on changing the temperature, pressure and adsorption of certain guest molecules. On the contrary, most of the porous solids like zeolites and activated carbon used in applications are rigid. The structural flexibility makes MOF materials very interesting to study and show promise in applications such as sensors, actuators, membrane separation and adsorptive separation. In this study, we examine the chemical potential difference (Δμ) of MIL-53 (Al), a …
Measurement Of Red Blood Cell Oxygenation State By Magnetophoresis, Nina A. Smith
Measurement Of Red Blood Cell Oxygenation State By Magnetophoresis, Nina A. Smith
ETD Archive
Magnetophoresis of red blood cells (RBCs) at varying partial pressures of oxygen (pO2) is hypothesized to rejuvenate stored blood to be utilized beyond the FDA regulated 42-day storage time. Magnetophoresis is a particle or cells motion induced by an applied magnetic field in a viscous media. The average magnetophoretic mobility of an oxygenated RBC is -0.126x10-6 mm3-s/kg, and a deoxygenated RBC is 3.66x10-6 mm3-s/kg, presenting magnetophoresis as a resource for RBC rejuvenation in hopes of storing it longer than 42 days. The main objective of this paper was to determine if controlling the pO2 within an RBC suspension, can singly- …
Chronoamperometry Analysis Of Sweat Sensor Technology, Evan Fritz
Chronoamperometry Analysis Of Sweat Sensor Technology, Evan Fritz
Williams Honors College, Honors Research Projects
Due to the demand for in-situ electrolyte sodium sensors, prototype sensors have been produced to create a product for athletes and marathoners to monitor hydration levels. These senors address a desire in the marketplace for athletic monitoring for overall athlete wellness and performance. Sweat sensor samples were created using Multi-walled Carbon Nanotubes functionalized on a Nylon-6 fiber mat using cyclo-oligomeric Calixarene. This production process produces sensors capable of detecting sodium ion concentration present in human sweat in presence of an electric current. Chronoamperometry analysis is used in this manner to determine the functionality of the sensors. Much of the research …
Application Of A Light Switchable System In Redirecting Escherichia Coli Metabolic Fluxes, Xintong Xia
Application Of A Light Switchable System In Redirecting Escherichia Coli Metabolic Fluxes, Xintong Xia
Graduate Theses - Chemical Engineering
Optogenetics has gained increasing attention for enabling reversible and non-invasive control in biochemical engineering. The purpose of this project is to investigate the application of a genetically engineered light-switchable system, Cph8-OmpR, for controlling the accumulation of the useful central metabolite glucose-6-phosphate (G6P) in Escherichia coli. This could be accomplished by linking expression of an adaptor protein, SspB, which increases enzyme phosphofructokinase (Pfk) degradation, with different light intensities. Pfk is the enzyme that catalyzes the conversion of fructose-6-phosphate (F6P), an isomer of G6P from an equilibrium reaction, to fructose 1,6-biphosphate for downstream metabolism. This step is considered the major control point …
Opto-Thermal Characterization Of Plasmon And Coupled Lattice Resonances In 2-D Metamaterial Arrays, Vinith Bejugam
Opto-Thermal Characterization Of Plasmon And Coupled Lattice Resonances In 2-D Metamaterial Arrays, Vinith Bejugam
Graduate Theses and Dissertations
Growing population and climate change inevitably requires longstanding dependency on sustainable sources of energy that are conducive to ecological balance, economies of scale and reduction of waste heat. Plasmonic-photonic systems are at the forefront of offering a promising path towards efficient light harvesting for enhanced optoelectronics, sensing, and chemical separations. Two-dimensional (2-D) metamaterial arrays of plasmonic nanoparticles arranged in polymer lattices developed herein support thermoplasmonic heating at off-resonances (near infrared, NIR) in addition to regular plasmonic resonances (visible), which extends their applicability compared to random dispersions. Especially, thermal responses of 2-D arrays at coupled lattice resonance (CLR) wavelengths were comparable …
A Proposed Process And Economic Analysis For A Manufacturing Facility For Nylon 6,6, Perry Doles
A Proposed Process And Economic Analysis For A Manufacturing Facility For Nylon 6,6, Perry Doles
Chemical Engineering Undergraduate Honors Theses
The global nylon market is a multi-billion-dollar industry that has been thriving in recent years due to advances in the process technology and its flexibility as a material. Nylon 6,6 is a versatile material with uses in many industries because of its ability manipulated into many forms. It is commonly used in applications that require heat resistance, chemical resistance, and high mechanical strength. It is commonly used in luggage, car parts, carpets, and many other plastic products that require the properties that nylon 6,6 exhibits. The versatility and demand for nylon 6,6 make it an attractive process for many potential …
Limits Of Small Scale Pressure Swing Adsorption, Aaron A. Moran
Limits Of Small Scale Pressure Swing Adsorption, Aaron A. Moran
ETD Archive
Portable or small scale pressure swing adsorption (PSA) systems have gained increasing popularity in both industry and literature due to the commercial success of personal oxygen concentrators (POCs). While these processes have much in common with larger PSA systems, significant differences exist that make understanding process limitations difficult. These include faster cycle times, smaller adsorbent particles, and a reduced column size. Macropore diffusion is traditionally assumed to control the mass transfer rate in columns packed with zeolite particles in an oxygen production process. While numerous studies have confirmed this assumption for the particle size used in industrial size PSA processes, …
High-Throughput Metabolism-Induced Toxicity Assays On A 384-Pillar Plate, Sooyeion Kang
High-Throughput Metabolism-Induced Toxicity Assays On A 384-Pillar Plate, Sooyeion Kang
ETD Archive
The U.S Environmental Protection Agency (EPA) launched the Transform Tox Testing Challenge in 2016 with the goal of developing practical methods that can be integrated into conventional high-throughput screening (HTS) assays to better predict the toxicity of parent compounds and their metabolites in vivo. In response to this need and to retrofit existing HTS assays for assessing metabolism-induced toxicity of compounds, we have developed a 384-pillar plate that is complementary to traditional 384-well plates and ideally suited for culturing human cells in three dimensions (3D) at a microscale. Briefly, human embryonic kidney (HEK) 293 cells in a mixture of alginate …
Treatment Of Dye Wastewater Using Dehydrated Peanut Hull, Nikitha Shamirpet
Treatment Of Dye Wastewater Using Dehydrated Peanut Hull, Nikitha Shamirpet
ETD Archive
The release of dye waste water into environment causes harm to aquatic life when they reach drains or other water sources. They pollute the soil and causes change in cycles of plant and animal life through bio-accumulation and nutrient cycle. Dyes which form residue or precipitate causes mutations or changes in the DNA of living organisms in and around the area of release of the dye into atmosphere. In this thesis, several runs were attempted to treat the synthetically prepared dye waste water using dehydrated peanut hull. The initial dye waste water samples were all collected and checked for absorbance, …
Effect Of History On The Binary Adsorption Equilibria Of Aluminium Terephthalate (Mil-53(Al)), Ufuoma Israel Kara
Effect Of History On The Binary Adsorption Equilibria Of Aluminium Terephthalate (Mil-53(Al)), Ufuoma Israel Kara
ETD Archive
Metal organic frameworks (MOFs) are highly porous solids with potential applications in a wide range of fields including gas separations and catalysis. Most of porous solids used in these applications such as zeolites and activated carbon usually have rigid structures. In contrast, a number of metal-organic frameworks (MOFs) exhibit structural transformation in response to external stimuli. Such materials show promise for applications such as sensors, actuators and adsorptive separations. Several thermodynamic formalisms were proposed in literature to explain this phenomenon, often known as gate-opening or “breathing” of the MOF material. In this study, the adsorptive behavior of MIL-53(Al), a MOF …
Determination Of Growth Kinetics, Yield Coefficients And Biodiesel Properties For The Green Microalgae Scenedesmus Dimorphus In Freshwater And Saline Medias, Morgan L. Cohara
Determination Of Growth Kinetics, Yield Coefficients And Biodiesel Properties For The Green Microalgae Scenedesmus Dimorphus In Freshwater And Saline Medias, Morgan L. Cohara
ETD Archive
Of the many alternative resources capable of generating biofuel, microalgal oil serves as a promising feedstock. Unfortunately, biodiesel production from microalgae is currently hindered by high operational costs. One primary causes for these high costs is the large quantity of freshwater required for cultivation. This experiment was designed to assess the feasibility of growing the green, freshwater microalgae Scenedesmus dimorphus in an increasingly saline environment. Both average yield coefficients and growth rates were monitored with increasing salt concentration. Determination of average yield coefficients allows for process scale-up and the optimization of production costs by minimizing raw material waste. Salinity was …
Kinetics And Ensemble Dynamics Of Colloidal Ellipsoids Near An Ac Electrode, Jiarui Yan
Kinetics And Ensemble Dynamics Of Colloidal Ellipsoids Near An Ac Electrode, Jiarui Yan
ETD Archive
The manipulation of colloidal particles via applying electric fields has been studied over the past 30 years due to the unique properties associated with the fabricated colloidal crystals. Most works in this field focused on utilizing an alternating current (AC) electric field with spherical particles. However, utilizing spherical colloidal particles as building blocks for complex microstructures has been challenging. Consequently, more recent work has shifted to employing complex colloids (anisotropic in nature) as building blocks for advanced materials. In our work, the phase diagram and the kinetics of assembling colloidal polystyrene ellipsoids under an AC electric field at low frequencies …
Influence Of Natural Convection During Dendritic Array Growth Of Metal Alloys (Gradient Freeze Directional Solidification), Suyog N. Mahajan
Influence Of Natural Convection During Dendritic Array Growth Of Metal Alloys (Gradient Freeze Directional Solidification), Suyog N. Mahajan
ETD Archive
Purpose of this study was to examine the microstructural evolution of primary dendrites during Gradient Freeze Directional Solidification process in cylindrical Pb-5.8% Sb alloy samples to generate the ground- based research data to support a future microgravity experiment on the Space Station in a convection free environment. Pb-5.8Sb was selected for this study because of its ease of processing and availability of physical property data which will be required for predicting the dendrite morphology parameters, such as, primary dendrite spacing and dendrite trunk diameter. This alloy is also susceptible to thermosolutal convection caused by density inversion of the met in …
Modeling Liver Diseases Using Hepatic Cell Microarrays, Alexander David Roth
Modeling Liver Diseases Using Hepatic Cell Microarrays, Alexander David Roth
ETD Archive
Hepatocellular carcinoma (HCC) is an invasive and aggressive cancer of the liver that arises due to chronic cirrhosis. Research into understanding HCC has focused on two-dimensional (2D) and three-dimensional (3D) technologies to simulate the liver microenvironment and use animal models to model how HCC affects the rest of the body. 3D hydrogel models are desired because they can mimic the transport behavior observed in vivo by structurally mimicking the extracellular matrix (ECM) without the ethical concerns of animal models. However, hydrogels can be toxic to cells and require optimal procedures for appropriate handling. In this study, we created 3D models …
Validating A Reduced-Order Model For Synthetic Jet Actuators Using Cfd And Experimental Data, Tim Persoons, Rick Cressall, Aliimohammadi Sajad
Validating A Reduced-Order Model For Synthetic Jet Actuators Using Cfd And Experimental Data, Tim Persoons, Rick Cressall, Aliimohammadi Sajad
Articles
Synthetic jet actuators (SJA) are emerging in various engineering applications, from flow separation and noise control in aviation to thermal management of electronics. A SJA oscillates a flexible membrane inside a cavity connected to a nozzle producing vortices. A complex interaction between the cavity pressure field and the driving electronics can make it difficult to predict performance. A reduced-order model (ROM) has been developed to predict the performance of SJAs. This paper applies this model to a canonical configuration with applications in flow control and electronics cooling, consisting of a single SJA with a rectangular orifice, emanating perpendicular to the …
Current State Of The Assets In The Chemical Engineering Laboratory At Rose-Hulman Institute Of Technology And Their Use In The Undergraduate Laboratory Course Sequence, Matthew Adams
Graduate Theses - Chemical Engineering
The Chemical Engineering Laboratory, also referred to as the Unit Operations (UO) Laboratory, is integral to any undergraduate Chemical Engineering curriculum as it provides students with the opportunity to gain practical and hands-on experience with processes that are commonplace throughout industry. The Chemical Engineering Department at Rose-Hulman Institute of Technology prides itself in providing its students with a practical education that will allow for an easy transition into industry as well as continued success throughout the students’ careers; as such, the assets in the Chemical Engineering Laboratory space and their use are paramount to this objective. The Chemical Engineering Department …
Beer, Booze, And Biofuels: An Introduction To Chemical Engineering, Kayla Revelle, Jacob Lambert, Kelly Kopchak
Beer, Booze, And Biofuels: An Introduction To Chemical Engineering, Kayla Revelle, Jacob Lambert, Kelly Kopchak
Senior Theses
The goal of this thesis project was to provide the layout, curriculum, and scheduling for an introductory course regarding chemical engineering for non-majors. Throughout the course of our studies in chemical engineering and engineering in general it had come to our attention that there were many myths regarding the classes and curriculum. We had heard countless times things such as “I am glad I’m not an engineering major”, “those classes seem so hard and boring”, or “It’s all math”. The purpose of this project and class was to dispel those myths and show non-majors what chemical engineering is all about. …
Pure And Binary Adsorption Equilibrium Of Nitrogen And Oxygen In Lilsx Zeolite, Himabindu Gandra
Pure And Binary Adsorption Equilibrium Of Nitrogen And Oxygen In Lilsx Zeolite, Himabindu Gandra
ETD Archive
Chemical products are made by combination of processes that includes synthesis, separation and purification. Separation processes comprises a large portion in these industries and are considered to be critical as most of the applications in chemical industries involves mixtures. Traditional separation methods such as distillation, evaporation, drying etc., requires high energy. For example, air separation to produce nitrogen and oxygen was previously practiced by cryogenic distillation that involves high pressure units and large energy requirement. On other hand, adsorption processes utilize less energy resources and is unique among separation methods. The phase separation is achieved by the existence of a …
Evaluation Of Mass Transfer Rate In Column Of Small Lilsx Particles, Mihikumar S. Patel
Evaluation Of Mass Transfer Rate In Column Of Small Lilsx Particles, Mihikumar S. Patel
ETD Archive
Air separation using zeolite based adsorption processes is a widely-studied topic. Proper process modeling is a key requirement to simulate the process. Conventional process modeling for air separation is designed for large scale adsorption processes using a long cycle time. However, advanced technology now permits to use of a short cycle time using small particles, which significantly reduces the size of the process.
Traditional process models were mostly developed for large particles (dp > 1.5 mm). Typically, it is safely assumed that intra particle diffusion controls the rate of the process while axial dispersion has a much smaller effect. This is …
Effect Of Convection Associated With Cross-Section Change During Directional Solidification Of Binary Alloys On Dendritic Array Morphology And Macrosegregation, Masoud Ghods
ETD Archive
This dissertation explores the role of different types of convection on macrosegregation and on dendritic array morphology of two aluminum alloys directionally solidified through cylindrical graphite molds having both cross-section decrease and increase. Al- 19 wt. % Cu and Al-7 wt. % Si alloys were directionally solidified at two growth speed of 10 and 29.1 µm s-1 and examined for longitudinal and radial macrosegregation, and for primary dendrite spacing and dendrite trunk diameter.
Directional solidification of these alloys through constant cross-section showed clustering of primary dendrites and parabolic-shaped radial macrosegregation profile, indicative of “steepling convection” in the mushy-zone. The degree …
Influence Of Cross-Section Change During Directional Solidification On Dendrite Morphology, Macrosegregation And Defect Formation In Pb-6 Wt Sb Alloy, Claudine Lacdao
Influence Of Cross-Section Change During Directional Solidification On Dendrite Morphology, Macrosegregation And Defect Formation In Pb-6 Wt Sb Alloy, Claudine Lacdao
ETD Archive
The purpose of this research is to examine the dendrite array morphology, macrosegregation, and defect formation caused by the fluid flow at the abrupt cross-section changes during directional solidification of Pb-6% Sb alloy. Four 24-cm long cylindrical alloy samples were directionally solidified in graphite crucibles: two having a constant diameter (9-mm) grown at 10.4 and 63.1 μm s-1 , one having an abrupt cross-section decrease (from 12.7 to 6.35 mm) and one having an abrupt increase (from 6.35 to 12.7 mm) by pulling down the alloy containing cylindrical graphite crucibles from the upper hot-zone of a stationary vertical furnace into …