Open Access. Powered by Scholars. Published by Universities.®

Chemical Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Missouri University of Science and Technology

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 211 - 240 of 2359

Full-Text Articles in Chemical Engineering

Method For Continuous Fabrication Of Multi-Functional Nanogels, Hu Yang, Da Huang Jan 2024

Method For Continuous Fabrication Of Multi-Functional Nanogels, Hu Yang, Da Huang

Patents

Nanogels and methods of synthesizing and using these nanogels are provided. The nanogels are formed by mixing a building block (e.g., polymer), crosslinker, preferably a target (e.g., biomedical compound or molecule), and a solvent in a multi-inlet vortex mixer, so as to cause the polymer and crosslinker to react and form a chemically crosslinked polymer network. In embodiments including a target, the target will be interspersed in and among that network and can be physically embedded and/or chemically bound therein.


Magnetic Separation Of Lunar Regolith Simulants With Applications To In Situ Resource Utilization On The Moon, Peter Bachle, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han Jan 2024

Magnetic Separation Of Lunar Regolith Simulants With Applications To In Situ Resource Utilization On The Moon, Peter Bachle, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han

Materials Science and Engineering Faculty Research & Creative Works

The development of in situ resource utilization (ISRU) for metal extraction is imperative as a steppingstone for habitation construction in lunar and non-terrestrial environments. Separation of minerals by chemical composition is important to optimize metal and oxygen liberation from lunar ore. to this effect, devices capable of separating aluminum bearing minerals from iron-bearing minerals from the lunar regolith simulants have been developed. Twenty-eight different simulants have been used in this study. a dual-belt separator was designed to reduce middlings. Para-magnetic minerals were reliably separated using a neodymium N52-magnet-separator system. Effective separation of aluminum-bearing minerals from iron-bearing minerals was greater than …


Beneficiation Of Lunar Regolith Simulants Through Electrostatic Sieving And Magnetic Separation, Peter Bachle, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han Jan 2024

Beneficiation Of Lunar Regolith Simulants Through Electrostatic Sieving And Magnetic Separation, Peter Bachle, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han

Materials Science and Engineering Faculty Research & Creative Works

In the light of future development of lunar structures, in-situ feldspar beneficiation is imperative for metal extraction. This research incorporates the tandem use of electrostatic sieving and magnetic separation for collecting a specific size range and mineral composition from lunar soil that optimizes subsequent chemical processing. While earlier works focused on silt-sized particles, this work expands that range up to medium-grained sand with a greater variety of potential lunar regolith compositions. This work shows that a 2.5 kV, 7 Hz to 30Hz frequency, single-phase square wave can lift silt and fine sand for collection. This lifting is successful directly from …


Kinetic Modeling Of Electrostatic Sieving For Lunar Regolith Beneficiation: Case Studies, Easton Ingram, Emmanuela Amen Eze, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han Jan 2024

Kinetic Modeling Of Electrostatic Sieving For Lunar Regolith Beneficiation: Case Studies, Easton Ingram, Emmanuela Amen Eze, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han

Materials Science and Engineering Faculty Research & Creative Works

A new kinetic particle modeling framework was developed to investigate electrostatic transport of lunar regolith particles with applications to the concept of electrostatic sieving. The new approach is based on kinetic particle dynamics and includes major modules of sampling the particle size distribution, solving electric fields, and tracking motion of charged dust grains. Case studies for a concept of electrostatic sieving were chosen to validate the new model. The simulation achieved similar yields reported in previous works, which served as validation of the model. The new model is computationally efficient and could serve as a design, analysis, and optimization tool.


Evaluation Of Novel Preformed Particle Gel System For Conformance Control In Mature Oil Reservoirs, Abdulaziz Almakimi, Ahmed Ben Ali, Ibnelwaleed A. Hussein, Baojun Bai Jan 2024

Evaluation Of Novel Preformed Particle Gel System For Conformance Control In Mature Oil Reservoirs, Abdulaziz Almakimi, Ahmed Ben Ali, Ibnelwaleed A. Hussein, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

To address challenges associated with excessive water production in mature oil reservoirs, this study introduces a carboxymethyl cellulose (CMC)-based material as a novel preformed particle gel (PPG) designed to plug excessive water pathways and redistribute the subsequent injected water toward unswept zones. Through microwave-assisted grafting copolymerization of CMC with acrylamide (AM), we successfully generated multi-sized dry particles within the range of 250–800 µm. Comprehensive analyses, including Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), have confirmed the chemical composition and morphology of the resulting carboxymethyl cellulose-grafted crosslinked polyacrylamide (CMC/PAMBA). Swelling kinetics and rheology tests were conducted to confirm the …


Kinetic Modeling Of Electrostatic Sieving For Lunar Regolith Beneficiation: Case Studies, Easton Ingram, Emmanuela Amen Eze, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han Jan 2024

Kinetic Modeling Of Electrostatic Sieving For Lunar Regolith Beneficiation: Case Studies, Easton Ingram, Emmanuela Amen Eze, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han

Materials Science and Engineering Faculty Research & Creative Works

A new kinetic particle modeling framework was developed to investigate electrostatic transport of lunar regolith particles with applications to the concept of electrostatic sieving. the new approach is based on kinetic particle dynamics and includes major modules of sampling the particle size distribution, solving electric fields, and tracking motion of charged dust grains. Case studies for a concept of electrostatic sieving were chosen to validate the new model. the simulation achieved similar yields reported in previous works, which served as validation of the model. the new model is computationally efficient and could serve as a design, analysis, and optimization tool.


Electrostatic Sorting Of Lunar Regolith Simulants For Sustainable Resource Utilization: Modeling And Characterization Of Particle Size Distribution, Abdullah Al Moinee, Peter Bachle, Kyle Newport, William Schonberg, David Bayless, Jeffrey Smith, Daoru Han, Fateme Rezaei Jan 2024

Electrostatic Sorting Of Lunar Regolith Simulants For Sustainable Resource Utilization: Modeling And Characterization Of Particle Size Distribution, Abdullah Al Moinee, Peter Bachle, Kyle Newport, William Schonberg, David Bayless, Jeffrey Smith, Daoru Han, Fateme Rezaei

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In pursuit of sustainable resource utilization on the Moon, this paper delves into modeling and characterization of particle size distribution (PSD) of lunar regolith simulants in an electrostatic system. A prototype electrostatic sieve was built and tested with four sample simulants mirroring properties of lunar mare and highland regolith. An alternating four-phase (90 degrees, 180 degrees, 270 degrees, 360 degrees) traveling square-wave was utilized for particle-directed transport to model the diverse trajectories of the particles. Numerically, we scrutinized how the distribution functions of the particles are manifested as the electrostatic field propagates, with a focus on three distinct particle ranges …


Design And Development Of Biocompatible Mofs And Silica-Based Nanocarriers With Controlled Pharmacokinetics For Drug Delivery Applications, Neila Pederneira Jan 2024

Design And Development Of Biocompatible Mofs And Silica-Based Nanocarriers With Controlled Pharmacokinetics For Drug Delivery Applications, Neila Pederneira

Doctoral Dissertations

"In the past decade, a big interest has drawn into nanoporous metal-organic frameworks (MOFs) and silica-based materials as nanocarriers for drug delivery applications, owing to their exceptionally high surface area and highly structured porous network. The overall goal of this research was to optimize the pharmacokinetic behavior of several highly porous biocompatible drug carriers that have the potential to carry Ibuprofen, 5-Fluorouracil, and Curcumin to the desired tissue without creating a burst effect and minimizing the amount of dosage and size that conventional capsules require. The specific objectives of this study are to (i) assess the effect of drug solubility …


Effect Of Various Irrigation Protocols And Antioxidant Application On Bonding Performance Of Two Adhesive Systems To Coronal Dentin, Nada Omar, Haidy N. Salem, Ahmed Abdou, Lamiaa M. Moharam Jan 2024

Effect Of Various Irrigation Protocols And Antioxidant Application On Bonding Performance Of Two Adhesive Systems To Coronal Dentin, Nada Omar, Haidy N. Salem, Ahmed Abdou, Lamiaa M. Moharam

Chemical and Biochemical Engineering Faculty Research & Creative Works

Background: The aim was to evaluate the effect of different irrigation protocols and antioxidants application on the shear bond strength (SBS) of two different adhesive systems to deep coronal dentin at different temperature. Material and Methods: One hundred and twenty human premolar teeth were cut longitudinally in two halves, then the prepared specimens were allocated into four main groups according to the irrigation protocols; Distilled water (control), Sodium hypochlorite (NaOCl) + Ethylenediamine Tetra-acetic Acid (EDTA), and NaOCl + Editronate (HEDP), two subgroups according to irrigation solutions temperature; 4°C and 37°C, two divisions according to grape seed extract (GSE) application (with …


The Comprehensive Study Of High Viscosity Friction Reducers In High-Tds And High-Temperature Environments, Xiaojing Ge Jan 2024

The Comprehensive Study Of High Viscosity Friction Reducers In High-Tds And High-Temperature Environments, Xiaojing Ge

Doctoral Dissertations

"High viscosity friction reducers (HVFRs) have been recently gaining more attention and increasing in use, not only as friction-reducing agents but also as proppant carriers. Reusing of produced water has also been driven by both environmental and economic benefits. Currently, most friction reducers on the market are anionic friction reducers, which are fully compatible with most produced water with low to medium level of Total Dissolved Solids (TDS) but show a significant drop at high TDS conditions in term of their friction reduction performance in most cases. On the contrary, cationic friction reducers are believed to have better TDS tolerance …


Investigating The Potential Of Blended Feedstocks For Biofuel Production Via Pyrolysis Process: Experimental And Aspen Simulation Approach, Hasan Jawad Hammood Al-Abedi Jan 2024

Investigating The Potential Of Blended Feedstocks For Biofuel Production Via Pyrolysis Process: Experimental And Aspen Simulation Approach, Hasan Jawad Hammood Al-Abedi

Doctoral Dissertations

"The development of renewable energy sources has become increasingly urgent considering the climate crisis and the need to reduce greenhouse gas emissions. Pyrolysis, which is decomposition of an organic feedstock without oxygen, is a thermo-chemical process that has garnered significant attention as a promising technology for sustainable energy production, capable of converting biomass and waste materials into biofuels.

The primary objective of this study is to investigate the pyrolysis and co-pyrolysis behaviors of corn stover (CS), refuse-derived fuel (RDF), and oil shale (OS) in equal mass ratios. Utilizing a thermogravimetric analyzer and differential scanning calorimetry (DSC), the co-pyrolysis process is …


Lithospheric Drip And Mantle Thermal Upwelling Beneath Central Asia And The Southern Great Plains Of North America: Evidence From Receiver Function Imaging, Yangyang Liao Jan 2024

Lithospheric Drip And Mantle Thermal Upwelling Beneath Central Asia And The Southern Great Plains Of North America: Evidence From Receiver Function Imaging, Yangyang Liao

Doctoral Dissertations

"Investigating the depth of mantle transition zone (MTZ) discontinuities provides insights into mantle dynamics, including regional-scale downwelling of mantle lithosphere (i.e., lithospheric drip) and upwelling of thermal materials (i.e., mantle plume). In our study, we employ receiver functions to image the 410 km (d410) and 660 km (d660) mantle discontinuities and to ascertain thickness of the MTZ beneath Central Asia and the Great Plains in United States. The findings unveil a significantly thickened transition zone, exhibiting an average thickness of 284 km beneath East Sayan. When considered alongside geochemical observations, our results indicate that the descent of the lithosphere is …


Sustainable Cementitious Materials For Building And Sorption Applications, Sukanta Kumar Mondal Jan 2024

Sustainable Cementitious Materials For Building And Sorption Applications, Sukanta Kumar Mondal

Doctoral Dissertations

"Ordinary Portland Cement (OPC) is the most widely used cement material, but it contributes over 8% of the global CO2 emission and the process is energy intensive. Moreover, OPC faces durability challenges, particularly in aggressive environments. Hence, there is rapidly increasing interest in sustainable alternative cements with lower carbon footprint, lower energy consumption, and those that offer superior properties that are beneficial for specific applications. Two sustainable cementitious materials that are frequently researched as an alternative to OPC are calcium sulfoaluminate (CSA) cement and alkali-activated materials (AAMs). CSA cement lowers CO2 emission by over 40% compared to OPC, …


Investigation Of Asphaltene Instability Under Gas Injection In Unconventional Reservoirs And Its Impact On Oil Recovery Performance, Mukhtar Elturki Jan 2024

Investigation Of Asphaltene Instability Under Gas Injection In Unconventional Reservoirs And Its Impact On Oil Recovery Performance, Mukhtar Elturki

Doctoral Dissertations

"Unconventional reservoirs, such as shale gas and tight oil formations, have become an important source of energy in recent years. However, these reservoirs often contain high levels of asphaltenes, which can lead to deposition and blockages in production wells and reduce the flow of hydrocarbons during gas enhanced oil recovery (GEOR) techniques. This study aims to experimentally evaluate the impact of miscible and immiscible carbon dioxide (CO₂) and nitrogen (N₂) on asphaltene deposition and its impact on oil recovery performance in unconventional shale reservoirs.

This research began with a comprehensive literature review and data analysis of GEOR methods in unconventional …


High Viscosity Friction Reducer Evaluation At High Temperature And High Tds Environments, Ghith Ali Ahmed Biheri Jan 2024

High Viscosity Friction Reducer Evaluation At High Temperature And High Tds Environments, Ghith Ali Ahmed Biheri

Doctoral Dissertations

"In unconventional reservoirs, proppant transport during hydraulic fracturing treatments could be successful when the proppant is placed further within the reservoir's fracture networks. This could increase the reservoir formation conductivities and improve the productivity of the wells. This job of improving the reservoir conductivity by distributing and transporting proppant can be conducted by reliable fracture fluids with excellent fluid rheology (e.g., viscosity and elasticity). However, several challenges, including the high temperatures and the presence of high TDS in produced water, may limit the capability of fracture fluids to transport proppant. Additionally, the use of fracture fluid has raised fears regarding …


Novel Supercritical Biodiesel Plant Design & Process Scale-Up, Ghana Shyam Paudel Jan 2024

Novel Supercritical Biodiesel Plant Design & Process Scale-Up, Ghana Shyam Paudel

Doctoral Dissertations

"Current energy prices, national energy security, and global climate change fuel our momentum to find efficient advanced fuels choices. In this study, biodiesel processing, and a novel design for next generation biodiesel plants are explored. During a National Science Foundation (NSF) I-Corps project we identified three creative and profitable improvements to the process: 1. Incorporating Energy intensive separations and reactions 2. Utilizing Low commodity glycerol and 3. Applying process intensification principles.

Current biodiesel processes are catalyzed processes using continuous stir reactors with distillation systems to separate material constituents. We tested a lab-scale nocatalyst supercritical biodiesel process using waste cooking oil …


Exploring Seismic Anisotropy In The Crust And Mantle Of The Tibetan Plateau And Analyzing Seismic Velocity Variations In Yellowstone, Cong Shen Jan 2024

Exploring Seismic Anisotropy In The Crust And Mantle Of The Tibetan Plateau And Analyzing Seismic Velocity Variations In Yellowstone, Cong Shen

Doctoral Dissertations

"Seismology is a scientific discipline that utilizes seismic waves to investigate the deep structures within the Earth's interior, which are otherwise inaccessible to direct observation by humans. These seismic waves can be categorized into two types: body waves and surface waves, each with distinct propagation modes and behaviors, carrying valuable information about their travel paths. The first paper concentrates on the analysis and inversion of body waves produced by large seismic events. It employs shear wave splitting and receiver function methods to explore the geodynamic structure of the south-central Tibetan Plateau, near the plate boundary. The investigation covers the depth …


Topography Of The 410 And 660 Km Discontinuities Beneath The Tibetan Plateau And Adjacent Areas, Zexin Miao Jan 2024

Topography Of The 410 And 660 Km Discontinuities Beneath The Tibetan Plateau And Adjacent Areas, Zexin Miao

Doctoral Dissertations

"The Tibetan Plateau represents the ongoing geotectonic aftermath of a continental collision initiated approximately 65 million years ago. Despite numerous seismological studies, controversies remain regarding the structure, evolution, and dynamics of the crust and mantle beneath Tibetan Plateau. In this study, we used teleseismic broadband data to investigate the topography of the mantle transition zone (MTZ) discontinuities. A total of ~655,000 receiver functions from 735 stations was utilized to image the 410 and 660 km discontinuities bordering the MTZ. Combining the observed and velocity corrected results, several areas in the central Tibet exhibit a typical d410 and an anomalously deep …


Investigation Wettability Contact Angle Using 2d Imaging Technology, Saleh Alsayegh Jan 2024

Investigation Wettability Contact Angle Using 2d Imaging Technology, Saleh Alsayegh

Doctoral Dissertations

"Investigation wetting preference of tight carbonate reservoir rocks and several other unconventional reservoir rocks, and their relation to oil production, is becoming noticeably important for field development in Kuwait, as in many future unconventional tight carbonate reservoirs in the Middle East. The overall objective of this investigating and modeling study is to discover many fundamental relationships from totality wettability preference as a tool for reservoir recovery predictions and management. The investigation includes advancing position of water wet preference into smaller capillaries of the matrix voids and incrementally more oil-wet into larger capillaries of natural fractures (NF). Also, investigating water/ oil …


Improving Syngas Quality In A Downdraft Biomass Gasifier With Blended Feedstocks, Rania Almusafir Jan 2024

Improving Syngas Quality In A Downdraft Biomass Gasifier With Blended Feedstocks, Rania Almusafir

Doctoral Dissertations

"Biomass gasification is the greatest potential renewable energy source and will play an important role in the energy mix of the future. To achieve a high quality of produced synthesis gas (syngas) in the gasification system, the syngas cleaning and cooling processes pose challenges. The main objectives of the present work are advancing the knowledge of the gasification process and producing syngas in the studied pilot-scale downdraft biomass gasifier.

A Thermogravimetric analysis (TGA) has been developed and utilized to experimentally investigate the impact of biomass feedstock diversity on the performance of the gasification process of hardwood (HW), softwood (SW) pellets, …


Paleoecological And Paleoclimatic Reconstructions Based On Holocene Sediment Cores, Lake Izabal, Eastern Guatemala, Erdoo Mongol Jan 2024

Paleoecological And Paleoclimatic Reconstructions Based On Holocene Sediment Cores, Lake Izabal, Eastern Guatemala, Erdoo Mongol

Doctoral Dissertations

"The Maya Region in Central America is characterized by pronounced discrepancies in precipitation, resulting in high precipitation gradients that support large-scale differences in vegetation across the region. Several lake deposits and other paleoclimate archives in the region have been studied to reconstruct past climates and palaeoecological conditions. However, actual data from proxy records have not been qualitatively and quantitatively utilized to interpret the behavior of the vegetation in moister areas within the Maya Region, such as the Lake Izabal Basin (LIB). The palynomorphs from two sediment cores in the LIB provided a good opportunity to infer the patterns of past …


Graphical Analysis And Revamping Of Crude Distillation Units Under Variable Operational Scenarios, Amany G. Abo-Mousa, Dina A. Kamel, Hany A. Elazab, Mamdouh A. Gadalla, Mai K. Fouad Dec 2023

Graphical Analysis And Revamping Of Crude Distillation Units Under Variable Operational Scenarios, Amany G. Abo-Mousa, Dina A. Kamel, Hany A. Elazab, Mamdouh A. Gadalla, Mai K. Fouad

Chemical and Biochemical Engineering Faculty Research & Creative Works

Energy Cost Represents a Significant Part of the Total Operating Costs of Many Processing Units. Crude Distillation is an Energy Intensive Process. Energy Integration is a Typical Solution to Reduce Heating and Cooling Utilities through Maximizing the Target Temperature of Crude Oil Streams Before Entering the Furnace. over the Past Few Decades, Significant Progress Has Been Made in Energy Integration Methods Including Pinch Technology and Mathematical Programming Approaches. Very Recently, Graphical Techniques Have Been Developed for Revamping Studies and Energy Analysis. Such Diagrams Are Valuable in Energy Targeting to Identity Energy Inefficiencies and Are Key to Potential Modifications for Maximum …


Covid-19 And The Chemical Industry: Impacts, Challenges, And Opportunities, Hossein Abedsoltan Dec 2023

Covid-19 And The Chemical Industry: Impacts, Challenges, And Opportunities, Hossein Abedsoltan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The COVID-19 pandemic imposed unparalleled challenges for the chemical industry, leading to disruptions in supply chains and demand dynamics. This period of crisis tested the adaptability and resilience of global chemical companies. Despite the challenges, the chemical industry exhibited remarkable innovation, collaboration, and adaptability. It demonstrated its capacity to respond swiftly and effectively to societal needs. Key lessons emerged, emphasizing the importance of diversifying supply chains, implementing scenario planning, and embracing digitalization for enhanced preparedness. As the world progresses toward recovery, the chemical industry is poised to leverage the valuable lessons learned. Industry 4.0 adoption, agile decision-making, and collaborative efforts …


Comparative Evaluation Of Caries Prevalence Among Group Of Egyptian Adolescents Using Dmfs And Icdasii Methods: A Cross-Sectional Study, Mohamed H. Zaazou, Dalia Y. Zaki, Ali Abdelnabi, Tamer M. Hamdy, Reham S. Saleh, Shahinaz N. Hassan, Zeinab M. Zaki, Lamiaa M. Moharam Dec 2023

Comparative Evaluation Of Caries Prevalence Among Group Of Egyptian Adolescents Using Dmfs And Icdasii Methods: A Cross-Sectional Study, Mohamed H. Zaazou, Dalia Y. Zaki, Ali Abdelnabi, Tamer M. Hamdy, Reham S. Saleh, Shahinaz N. Hassan, Zeinab M. Zaki, Lamiaa M. Moharam

Chemical and Biochemical Engineering Faculty Research & Creative Works

Background: Limited data is available regarding the prevalence of dental caries as a chronic disease among adolescents using different caries assessment indices. The aim of this study was to compare and describe the prevalence of dental caries among group of Egyptian students using two caries assessment indices: DMFS and ICDAS II. Methods: This descriptive, cross-sectional epidemiological study included 2760 public secondary school students with age range from 15 to 18 years with permanent dentition and good general health. Presence of; retained teeth, congenital or developmental anomalies in the permanent dentition, orthodontic treatments, systematic conditions, smoking and general health problems were …


A Review On Liquid Flow Through Low-Density Fibrous Porous Media, Hossein Abedsoltan Dec 2023

A Review On Liquid Flow Through Low-Density Fibrous Porous Media, Hossein Abedsoltan

Chemical and Biochemical Engineering Faculty Research & Creative Works

This review focuses on studying liquid flow through low-density fibrous porous media, particularly tissue grades of papers. It discusses experimental designs, factors affecting liquid flow, and various versions of the Lucas-Washburn equation and permeability expressions used to estimate liquid flow in these media. While a comprehensive model for liquid flow in these materials is lacking due to their structural complexity, numerous experimental methods have been developed to determine absorption properties, particularly for wiping and cleaning liquids. The review covers these methods, many of which are proposed by standard organizations. It is a valuable reference for scientists interested in understanding the …


Evaluation Of Different Decontamination Procedures On Bond Strength To Sound And Caries Affected Dentin Using “No-Wait” Universal Adhesive, Lamiaa M. Moharam, Haidy N. Salem, Sherif Khadr, Ahmed Abdou Dec 2023

Evaluation Of Different Decontamination Procedures On Bond Strength To Sound And Caries Affected Dentin Using “No-Wait” Universal Adhesive, Lamiaa M. Moharam, Haidy N. Salem, Sherif Khadr, Ahmed Abdou

Chemical and Biochemical Engineering Faculty Research & Creative Works

Background: Current study aimed to evaluate the effect of different decontamination procedures on micro-shear bond strength (μSBS) of sound (SoD) and caries-affected dentin (CAD) of two universal adhesives after blood-saliva contamination. Methods: One hundred and eighty bovine anterior teeth were prepared and allocated into the respective groups according to tested dentin substrates [SoD, CAD], universal adhesives [Clearfil Bond Universal Quick (UBQ), All-Bond-Universal (ABU)], adhesive contamination stage [none, contamination before and after adhesives light-curing], and according to decontamination procedures [no decontamination, water rinsing, adhesive rebond, Ethylenediaminetetraacetic acid (ETDA) and chlorhexidine (CHX) application]. Universal adhesives were applied according to manufacturer instructions in …


Preclassic Environmental Degradation Of Lake Petén Itzá, Guatemala, By The Early Maya Of Nixtun-Ch’Ich’, Brooke A. Birkett, Jonathan Obrist-Farner, Prudence M. Rice, Wesley G. Parker, Peter M.J. Douglas, Melissa A. Berke, Audrey K. Taylor, Jason H. Curtis, Benjamin Keenan Dec 2023

Preclassic Environmental Degradation Of Lake Petén Itzá, Guatemala, By The Early Maya Of Nixtun-Ch’Ich’, Brooke A. Birkett, Jonathan Obrist-Farner, Prudence M. Rice, Wesley G. Parker, Peter M.J. Douglas, Melissa A. Berke, Audrey K. Taylor, Jason H. Curtis, Benjamin Keenan

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Paleolimnological Evidence Indicates the Ancient Maya Transformed Terrestrial Ecosystems by Felling Forest Vegetation to Construct Large Civic-Ceremonial Centers and to Expand Agriculture. Human Settlements Influenced Lacustrine Environments But the Effects of Maya Activities on Aquatic Ecosystems Remain Poorly Studied. Here We Analyzed a Sediment Core from Lake Petén Itzá, Guatemala, to Infer Paleoenvironmental Changes Resulting from Maya Occupation of the Archaeological Site of Nixtun-Ch'ich'. Increases in Charcoal and Fecal Stanol Concentrations Indicate Maya Occupation of the Candelaria Peninsula by the Late Early Preclassic Period. Geochemical Proxies Reveal a Period of Lake Ecosystem Alteration during Construction and Expansion of the City's …


A Novel Renewable Energy Powered Zero Liquid Discharge Scheme For Ro Desalination Applications, Mamdouh A. Gadalla, Amr Abdel Fatah, Hany A. Elazab Dec 2023

A Novel Renewable Energy Powered Zero Liquid Discharge Scheme For Ro Desalination Applications, Mamdouh A. Gadalla, Amr Abdel Fatah, Hany A. Elazab

Chemical and Biochemical Engineering Faculty Research & Creative Works

This work proposes a conceptual model for a Zero Liquid Discharge (ZLD) for Reverse Osmosis (RO) desalination. The model describes a Process Flow Diagram (PFD). The proposed process relies on an RO followed by electrolyser, solar evaporator and mixing tank. The water reject from the RO is split into three fractions, one to an electrolyser to produce H2, another to solar evaporator to produce fresh water, third is remixed with water from the evaporator to reduce the salinity of the RO feed. The hydrogen produced in the electrolyser is burned and its energy is stored using cement blocks. The evaporator …


New Dual Modality Technique Of Gamma-Ray Densitometry (Grd) And Optical Fiber Probe (Ofp) To Investigate Line-Averaged Diameter Profiles Of Gas, Liquid, And Solid Holdups Along The Height Of A Slurry Bubble Column, Omar Farid, Binbin Qi, Sebastián Uribe, Muthanna H. Al-Dahhan Nov 2023

New Dual Modality Technique Of Gamma-Ray Densitometry (Grd) And Optical Fiber Probe (Ofp) To Investigate Line-Averaged Diameter Profiles Of Gas, Liquid, And Solid Holdups Along The Height Of A Slurry Bubble Column, Omar Farid, Binbin Qi, Sebastián Uribe, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

A new hybrid measurement technique was developed and employed to study line-averaged three-phase holdup distribution in a Slurry Bubble Column Reactor (SBCR) using gamma-ray densitometry (GRD) and point optical fiber probe (OFP) techniques. The OFP technique was used to measure the local gas holdup at 45 nodes in the cross-section area of the SBCR at three different axial levels. Thus, the GRD technique measured the spectrum of the SBCR for two different orientations simultaneously with the OFP technique at the same operating conditions to determine the solid holdup distribution radially and axially. The line-averaged solid holdup for 25% solids loading …


Development Of Eco-Friendly Chitosan-G-Polyacrylamide Preformed Particle Gel For Conformance Control In High-Temperature And High-Salinity Reservoirs, Reem Elaf, Ahmed Ben Ali, Mohammed Saad, Ibnelwaleed A. Hussein, Baojun Bai Nov 2023

Development Of Eco-Friendly Chitosan-G-Polyacrylamide Preformed Particle Gel For Conformance Control In High-Temperature And High-Salinity Reservoirs, Reem Elaf, Ahmed Ben Ali, Mohammed Saad, Ibnelwaleed A. Hussein, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Oil and gas extraction has become challenging nowadays due to the accompanying amount of excess produced water that results in poor recoverability of hydrocarbon, besides other environmental and economic isues. A recent and efficient technology for conformance control is the injection of preformed particle gels (PPGs), which results in a more practical production process. Nevertheless, existing treatments fail in high-temperature reservoirs, are extremely sensitive to salinity, and are hazardous. The characteristics of the designed PPG, such as mechanical strength and thermal durability, is mainly depend on their crosslinking method. Polysaccharides-based gels prepared by physical crosslinking are weaker than the ones …