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Articles 2371 - 2400 of 14120

Full-Text Articles in Engineering

The Influence Of Tropical Atlantic Sea-Surface Temperatures And The North Atlantic Subtropical High During The Maya Droughts, Derek K. Gibson, Jonathan Obrist-Farner, Brooke A. Birkett, Jason H. Curtis, Melissa A. Berke, Peter M.J. Douglas, Prudence M. Rice, Jeremy Maurer Jan 2023

The Influence Of Tropical Atlantic Sea-Surface Temperatures And The North Atlantic Subtropical High During The Maya Droughts, Derek K. Gibson, Jonathan Obrist-Farner, Brooke A. Birkett, Jason H. Curtis, Melissa A. Berke, Peter M.J. Douglas, Prudence M. Rice, Jeremy Maurer

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The frequency and duration of Late-Holocene hydrologic extremes in northern Guatemala were investigated using multiple sedimentological and geochemical proxies preserved in a sediment core collected from Lake Petén Itzá. A general trend of increasing aridity in the Maya Lowlands during the past 2000 years was punctuated by several multidecadal- to centennial-scale drought events recorded in the Petén Itzá sediments. In particular, the period spanning the Maya Terminal Classic Period and the Medieval Climate Anomaly (MCA), between 800 and 1300 CE, was marked by several extreme droughts and included the driest conditions of the past 2000 years between 950 and 1100 …

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Drainage And Sedimentary Response Of The Northern Andes And The Pebas System To Miocene Strike-Slip Tectonics: A Source To Sink Study Of The Magdalena Basin, S. Zapata, L. Calderon-Diaz, C. Jaramillo, Francisca Oboh-Ikuenobe, J. C. Piedrahita, M. Rodríguez-Cuevas, A. Cardona, E. R. Sobel, M. Parra, V. Valencia, A. Patiño, J. S. Jaramillo-Rios, M. Flores, J. Glodny Jan 2023

Drainage And Sedimentary Response Of The Northern Andes And The Pebas System To Miocene Strike-Slip Tectonics: A Source To Sink Study Of The Magdalena Basin, S. Zapata, L. Calderon-Diaz, C. Jaramillo, Francisca Oboh-Ikuenobe, J. C. Piedrahita, M. Rodríguez-Cuevas, A. Cardona, E. R. Sobel, M. Parra, V. Valencia, A. Patiño, J. S. Jaramillo-Rios, M. Flores, J. Glodny

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Miocene strike-slip tectonics was responsible for creating and closing short-lived (ca. 6 Ma) passages and the emergence of isolated topography in the Northern Andes. These geological events likely influenced the migration and/or isolation of biological populations. To better understand the paleogeography of the Miocene hinterland and foreland regions in the Northern Andes, we conducted a source-to-sink approach in the Magdalena Basin. This basin is located between the Central and Eastern Cordilleras of Colombia and contains an ample Miocene record, which includes Lower Miocene fine-grained strata and Middle Miocene to Pliocene coarsening-up strata. Our study presents a new data set that …

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Study Of Legionella Pneumophila Treatment With Copper In Drinking Water By Single Cell-Icp-Ms, Lei Xu, Austin Sigler, Anna Chernatynskaya, Lindsey Rasmussen, Jingrang Lu, Endalkachew Sahle-Demessie, David J. Westenberg, Hu Yang, Honglan Shi Jan 2023

Study Of Legionella Pneumophila Treatment With Copper In Drinking Water By Single Cell-Icp-Ms, Lei Xu, Austin Sigler, Anna Chernatynskaya, Lindsey Rasmussen, Jingrang Lu, Endalkachew Sahle-Demessie, David J. Westenberg, Hu Yang, Honglan Shi

Biological Sciences Faculty Research & Creative Works

Legionella pneumophila is a persistent opportunistic pathogen that poses a significant threat to domestic water systems. Previous studies suggest that copper (Cu) is an effective antimicrobial in water systems. A rapid and sensitive quantification method is desired to optimize the conditions of L. pneumophila treatment by Cu and to better understand the interaction mechanisms between Cu and cells. In this study, we developed a highly sensitive single cell (SC)-ICP-MS method to monitor L. pneumophila cell concentration and track their uptake of Cu. The SC-ICP-MS method showed excellent sensitivity (with a cell concentration detection limit of 1000 cells/mL), accuracy (good agreement …

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Cyberphysical Systems And Energy: A Discussion With Reference To An Enhanced Geothermal Process, Keshav Kasturi Rangan, Henrique Oyama, Ilham Azali Assoumani, Helen Durand, K.Y. Simon Ng Jan 2023

Cyberphysical Systems And Energy: A Discussion With Reference To An Enhanced Geothermal Process, Keshav Kasturi Rangan, Henrique Oyama, Ilham Azali Assoumani, Helen Durand, K.Y. Simon Ng

Chemical Engineering and Materials Science Faculty Research Publications

As cyberphysical systems research advances, energy systems will be able to benefit from the developments. In this section, we discuss several points in two newer areas for cyberphysical systems research in chemical engineering: 1) cybersecurity of process control systems; and 2) quantum computation of control actions. The discussion is presented in a general manner, with relevance to flow systems or under traditional control laws (e.g., proportional control). However, to showcase energy systems relevance, we will provide links, at intervals, between the developments discussed and enhanced geothermal systems with energy production through the Organic Rankine Cycle (ORC).

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Descriptive Systematics Of Upper Palaeocene–Lower Eocene Pollen And Spores From The Northern Niger Delta, South-Eastern Nigeria, Luke Mander, Carlos Jaramillo, Francisca Oboh-Ikuenobe Jan 2023

Descriptive Systematics Of Upper Palaeocene–Lower Eocene Pollen And Spores From The Northern Niger Delta, South-Eastern Nigeria, Luke Mander, Carlos Jaramillo, Francisca Oboh-Ikuenobe

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Fossil pollen and spores are a vital source of information on the geological history of tropical vegetation including reconstructions of vegetation diversity and composition. However, such work relies on a sound taxonomic framework, and this is challenging to achieve because of the large number of pollen and spore morphotypes that are encountered in palynological preparations from tropical sediments. In tropical West Africa, for example, extensive taxonomic work on Cretaceous–Paleogene pollen and spores was undertaken in the later part of the twentieth century, but more recent palynological work has focused on stratigraphy and basin evolution, and there is a need for …

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Assessment Of The Dimensionless Groups-Based Scale-Up Of Gas–Solid Fluidized Beds, Faraj M. Zaid, Haider Al-Rubaye, Thaar M. Aljuwaya, Muthanna H. Al-Dahhan Jan 2023

Assessment Of The Dimensionless Groups-Based Scale-Up Of Gas–Solid Fluidized Beds, Faraj M. Zaid, Haider Al-Rubaye, Thaar M. Aljuwaya, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The most common scale-up approach for gas–solids fluidized beds is based on matching the governing dimensionless parameters. In the literature, this approach has been validated only by means of measuring global parameters between different sizes of fluidized beds. However, such global measurements are not sufficient to depict all the interplaying hydrodynamic phenomena and hence verify the scale-up relationships. Therefore, to assess this approach, an advanced gas–solids optical probe and pressure transducer measurement techniques have been applied to quantify local hydrodynamic parameters in two different sized fluidized beds. Four different sets of experimental conditions were designed and conducted to examine the …

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Review Of The Fluid Dynamics And Heat Transport Phenomena In Packed Pebble Bed Nuclear Reactors, Rahman S. Almusafir, Ahmed A. Jasim, Muthanna H. Al-Dahhan Jan 2023

Review Of The Fluid Dynamics And Heat Transport Phenomena In Packed Pebble Bed Nuclear Reactors, Rahman S. Almusafir, Ahmed A. Jasim, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Knowledge and proper safety analyses of the gas coolant and heat transport mechanism in the dynamic core of packed pebble bed nuclear reactors pose challenges to the reliable design and efficient operation of these reactors. Therefore, this paper carefully reviews most of the gas coolant mixing and heat transport studies performed for the fluid flow and heat transfer processes in packed pebble bed reactors (PBRs). It begins with a brief introduction and description of nuclear PBRs. The second section summarizes the physical characteristics of packed bed reactors in terms of the bed structure (porosity) and its radial and axial distributions. …

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Development And Assessment Of Magnetic Fe2o3@Mof-74 Composite Sorbents For Ethylene/Ethane Separation, Khaled Baamran, Kyle Newport, Ali A. Rownaghi, Fateme Rezaei Jan 2023

Development And Assessment Of Magnetic Fe2o3@Mof-74 Composite Sorbents For Ethylene/Ethane Separation, Khaled Baamran, Kyle Newport, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

Development of smart sorbents that can be regenerated when triggered by external stimuli such as magnetic field can overcome the poor energy utilization of the current sorbents investigated for light olefins/paraffins separation. In this work, we report the development of novel magnetic sorbents comprising of MOF-74 crystals and superparamagnetic Fe2O3 particles in a core–shell structure, and assessment of their C2H4/C2H6 separation performance. The electromagnetic properties of the materials were tuned by varying the Fe2O3 (Fex) loading (x = 1–20 wt%), and their effects on adsorption …

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Techno-Economic And Life Cycle Analyses For A Supercritical Biodiesel Production Process From Waste Cooking Oil For A Plant Located In The Midwest United States, Prashant Nagapurkar, Joseph D. Smith Jan 2023

Techno-Economic And Life Cycle Analyses For A Supercritical Biodiesel Production Process From Waste Cooking Oil For A Plant Located In The Midwest United States, Prashant Nagapurkar, Joseph D. Smith

Chemical and Biochemical Engineering Faculty Research & Creative Works

Existing Literature Lacks Detailed Techno-Economic and Environmental Life Cycle Analyses (TEA-LCA) Focused on Supercritical Biodiesel Production Pathways Produced Via Waste Products. Therefore, in This Work, the TEA-LCA Was Conducted to Generate Supercritical Biodiesel from Waste Cooking Oil for Plants Located in the Midwest Region of USA Having Annual Production Capacities of 10,600 and 128,000 T using Aspen Plus and GREET Software. Two Plant Production Capacities Were Chosen to Capture the Economies of Scale Impact on Biodiesel Manufacture Cost. in the Supercritical Process, Methanol and Propane Were Used as a Cosolvent to Synthesize Biodiesel from Waste Cooking Oil (WCO) at 280 …

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3d-Printed Boron Nitride Catalytic Monoliths For Oxidative Dehydrogenation Of Propane, Theodore Agbi, Wei Shang Lo, Khaled Baamran, Taekyung Ryu, Christine Cheung, Fateme Rezaei, Ive Hermans Jan 2023

3d-Printed Boron Nitride Catalytic Monoliths For Oxidative Dehydrogenation Of Propane, Theodore Agbi, Wei Shang Lo, Khaled Baamran, Taekyung Ryu, Christine Cheung, Fateme Rezaei, Ive Hermans

Chemical and Biochemical Engineering Faculty Research & Creative Works

Boron-containing materials are efficient catalysts for the oxidative dehydrogenation of propane to propylene, proceeding via radical intermediates. The radical mechanism is initiated by the solid surface and propagated in the gas phase. It has been hypothesized that the propylene selectivity could be increased by enhancing the gas-phase contributions by favoring the formation of iso- over n-propyl radical intermediates. Indeed, whereas n-propyl radicals can be converted to both propylene and ethylene, iso-propyl radicals yield exclusively propylene. In this contribution, we explore 3D printing to structure the hexagonal boron nitride (hBN) heterogeneous catalyst with high void space. 3D-printed hBN monoliths were found …

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Influence Of Interfering Ions And Adsorption Temperature On Radioactive Iodine Removal Efficiency And Stability Of Ni-Mof-74 And Zr-Uio-66, Turki Alghamdi, Peter O. Aina, Ali A. Rownaghi, Fateme Rezaei Jan 2023

Influence Of Interfering Ions And Adsorption Temperature On Radioactive Iodine Removal Efficiency And Stability Of Ni-Mof-74 And Zr-Uio-66, Turki Alghamdi, Peter O. Aina, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

Metal-organic frameworks (MOFs) often exhibit an exceptional adsorption-based separation performance for a variety of gases, ions, and liquids. While most radioactive iodine removal studies focus on the capture of radioactive iodine from off-gas streams, few studies have systematically investigated the effect of structure-property relationships of MOFs on iodine removal performance in the presence of interfering ions in liquid solutions. Herein, we investigated the iodide ion (I-) adsorption performance of two model MOFs (e.g., Ni-MOF-74 and Zr-UiO-66) in liquid phase as a function of iodine concentration (e.g., 0.125 to 0.25 and 0.50 mmol/L) and adsorption temperature (e.g., 25 to …

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Ptco/Mwcnts Prepared By A Microwave-Assisted Polyol Method For Selective Cinnamaldehyde Hydrogenation, Kaiying Wang, Yuzi Liu, Jee-Ching Wang, Xinhua Liang Jan 2023

Ptco/Mwcnts Prepared By A Microwave-Assisted Polyol Method For Selective Cinnamaldehyde Hydrogenation, Kaiying Wang, Yuzi Liu, Jee-Ching Wang, Xinhua Liang

Chemical and Biochemical Engineering Faculty Research & Creative Works

Using microwave irradiation, PtCo alloy nanoparticles were deposited within a few minutes on COOH-functionalized MWCNT supports. The obtained catalysts were used for selective hydrogenation of cinnamaldehyde, a reaction whose products are widely used in various fields. In the selective cinnamaldehyde hydrogenation to cinnamyl alcohol, microwave-prepared catalysts (generically, PtxCoy-MW) outperformed a catalyst prepared by the conventional method (Pt1Co2-con). The highest selective hydrogenation to cinnamyl alcohol, 89%, was obtained using Pt1Co2-MW, while Pt1Co2-con showed a selectivity of 76%. Characterization results confirmed that the microwave prepared samples …

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Simulation And Optimization Of Waste Heat To Electricity Through Organic Rankine Cycles (Orcs): A Case Study In An Oil Refinery, Mohamed A. Sadek, Mamdouh A. Gadalla, Noran Shedid, Dina Ahmed, Hany A. Elazab Jan 2023

Simulation And Optimization Of Waste Heat To Electricity Through Organic Rankine Cycles (Orcs): A Case Study In An Oil Refinery, Mohamed A. Sadek, Mamdouh A. Gadalla, Noran Shedid, Dina Ahmed, Hany A. Elazab

Chemical and Biochemical Engineering Faculty Research & Creative Works

Energy efficiency has become a global problem that is detrimental to the chemical industries technically, economically and to the environment. Organic Rankine Cycle (ORC) is a promising technology that can solve this problem by recovering heat from low-grade waste heat sources by using organic working fluids. The heat source for the ORC system used in this article is air leaving air coolers in an oil refinery with a temperature of 140o C. The heat exchanger data for this refinery was used in the simulation of a basic cycle and a regenerative cycle using ASPEN HYSYS V.10. These ORC systems were …

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Demonstration Of High Detoxification Efficiency Of Glassy Polymer-Metal Hydroxide Composites Toward Chemical Warfare Agent Simulants, Peter O. Aina, Sukanta K. Mondal, Joshua Costain, Ali A. Rownaghi, Fateme Rezaei Jan 2023

Demonstration Of High Detoxification Efficiency Of Glassy Polymer-Metal Hydroxide Composites Toward Chemical Warfare Agent Simulants, Peter O. Aina, Sukanta K. Mondal, Joshua Costain, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

The design and development of polymeric composites that can effectively capture and destruct toxic chemicals with a fast detoxification rate is of high importance for protecting the military, first responders, and civilians. Here we report the synthesis and assessment of zirconium hydroxide (Zr (OH)4)-incorporated Ultem, Matrimid, and PIM-1 composites for detoxification of dimethyl 4-nitrophenylphosphonate (DMNP), as a type G toxic nerve agent simulant. Maintaining homogeneity, three different loadings (8, 20, 30 wt %) of Zr (OH)4 were incorporated into the polymers, and the thin films of composite materials were developed for subsequent hydrolysis tests. Our results indicated that increasing the …

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Development, Validation And Implementation Of Multiple Radioactive Particle Tracking Technique, Mehul S. Vesvikar, Thaar M. Aljuwaya, Mahmoud M. Taha, Muthanna H. Al-Dahhan Jan 2023

Development, Validation And Implementation Of Multiple Radioactive Particle Tracking Technique, Mehul S. Vesvikar, Thaar M. Aljuwaya, Mahmoud M. Taha, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Computer Automated Radioactive Particle Tracking (CARPT) technique has been successfully utilized to measure the velocity profiles and mixing parameters in different multiphase flow systems where a single radioactive tracer is used to track the tagged phase. However, many industrial processes use a wide range of particles with different physical properties where solid particles could vary in size, shape and density. For application in such systems, the capability of current single tracer CARPT can be advanced to track more than one particle simultaneously. Tracking multiple particles will thus enable to track the motion of particles of different size shape and density, …

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Kinetic Assessment Of Light Hydrocarbons Separation Over Fe-Doped 13x Composite Sorbents Under Multicomponent Feed Conditions, Khaled Baamran, Jimmy D.L. Moreno, Ali A. Rownaghi, Fateme Rezaei Jan 2023

Kinetic Assessment Of Light Hydrocarbons Separation Over Fe-Doped 13x Composite Sorbents Under Multicomponent Feed Conditions, Khaled Baamran, Jimmy D.L. Moreno, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

Current sorbents investigated for light olefin/paraffin separation usually suffer from low selectivity. Besides, multicomponent analysis of this important separation is usually overlooked in the literature. To enhance the separation efficiency of zeolite 13X, we developed a series of Fe2O3/13X composite sorbents and assessed their separation performance using binary, ternary, and multicomponent gas mixtures of C2H4, C2H6, CH4, and H2. In these composites, nano- and micro Fe2O3 particles (NPs and MPs) with varied loadings were used, while Fe was also ion-exchanged into …

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Hydrothermal Stability Of Na-Lta Shaped With Clay Binder, Jimmy D.L. Moreno, Daniele Da S. Pereira, Thalita M. Azevedo, Dárley C. De Melo, Debora A.S. Maia, Fateme Rezaei, Moisés Bastos-Neto, Diana C.S. De Azevedo Jan 2023

Hydrothermal Stability Of Na-Lta Shaped With Clay Binder, Jimmy D.L. Moreno, Daniele Da S. Pereira, Thalita M. Azevedo, Dárley C. De Melo, Debora A.S. Maia, Fateme Rezaei, Moisés Bastos-Neto, Diana C.S. De Azevedo

Chemical and Biochemical Engineering Faculty Research & Creative Works

Gas drying by adsorption on molecular sieves is one of the first unit operations in natural gas processing. Nevertheless, the thermal swings during regeneration combined with the presence of a complex gas mixture may lead to early adsorbent fouling. The shaping of adsorbent materials is crucial not only to reduce pressure drop in columns, but also for enhanced thermal and mechanical properties. In this work, synthesized sodium-based zeolite Linde Type A (Na-LTA) in powder was shaped by extrusion into cylindrical pellets using a clay binder followed by calcination at 673 K for 24 h. The produced 2-mm pellets had binder …

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Assessment Of The Dimensionless Groups-Based Scale-Up Of Gas–Solid Fluidized Beds, Faraj M. Zaid, Haider Al-Rubaye, Thaar M. Aljuwaya, Muthanna H. Al-Dahhan Jan 2023

Assessment Of The Dimensionless Groups-Based Scale-Up Of Gas–Solid Fluidized Beds, Faraj M. Zaid, Haider Al-Rubaye, Thaar M. Aljuwaya, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The most common scale-up approach for gas–solids fluidized beds is based on matching the governing dimensionless parameters. in the literature, this approach has been validated only by means of measuring global parameters between different sizes of fluidized beds. However, such global measurements are not sufficient to depict all the interplaying hydrodynamic phenomena and hence verify the scale-up relationships. Therefore, to assess this approach, an advanced gas–solids optical probe and pressure transducer measurement techniques have been applied to quantify local hydrodynamic parameters in two different sized fluidized beds. Four different sets of experimental conditions were designed and conducted to examine the …

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Reactive Oxygen Species (Ros)-Responsive Size-Reducible Nanoassemblies For Deeper Atherosclerotic Plaque Penetration And Enhanced Macrophage-Targeted Drug Delivery, Jianhua He, Wenli Zhang, Xiaoju Zhou, Fengfei Xu, Jiahui Zou, Qiqi Zhang, Yi Zhao, Hongliang He, Hu Yang, Jianping Liu Jan 2023

Reactive Oxygen Species (Ros)-Responsive Size-Reducible Nanoassemblies For Deeper Atherosclerotic Plaque Penetration And Enhanced Macrophage-Targeted Drug Delivery, Jianhua He, Wenli Zhang, Xiaoju Zhou, Fengfei Xu, Jiahui Zou, Qiqi Zhang, Yi Zhao, Hongliang He, Hu Yang, Jianping Liu

Chemical and Biochemical Engineering Faculty Research & Creative Works

Nanoparticle-Based therapeutics represent potential strategies for treating atherosclerosis; however, the complex plaque microenvironment poses a barrier for nanoparticles to target the dysfunctional cells. Here, we report reactive oxygen species (ROS)-responsive and size-reducible nano assemblies, formed by multivalent host-guest interactions between β-cyclodextrins (β-CD)-anchored discoidal recombinant high-density lipoprotein (NP3ST) and hyaluronic acid-ferrocene (HA-Fc) conjugates. the HA-Fc/NP3ST nano assemblies have extended blood circulation time, specifically accumulate in atherosclerotic plaque mediated by the HA receptors CD44 highly expressed in injured endothelium, rapidly disassemble in response to excess ROS in the intimal and release smaller NP3ST, allowing for further plaque penetration, macrophage-targeted cholesterol efflux and …

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Nanomaterial Payload Delivery To Central Nervous System Glia For Neural Protection And Repair, Jayant Saksena, Adelle E. Hamilton, Ryan J. Gilbert, Jonathan M. Zuidema Jan 2023

Nanomaterial Payload Delivery To Central Nervous System Glia For Neural Protection And Repair, Jayant Saksena, Adelle E. Hamilton, Ryan J. Gilbert, Jonathan M. Zuidema

Chemical and Biochemical Engineering Faculty Research & Creative Works

Central nervous system (CNS) glia, including astrocytes, microglia, and oligodendrocytes, play prominent roles in traumatic injury and degenerative disorders. Due to their importance, active pharmaceutical ingredients (APIs) are being developed to modulate CNS glia in order to improve outcomes in traumatic injury and disease. While many of these APIs show promise in vitro, the majority of APIs that are systemically delivered show little penetration through the blood–brain barrier (BBB) or blood-spinal cord barrier (BSCB) and into the CNS, rendering them ineffective. Novel nanomaterials are being developed to deliver APIs into the CNS to modulate glial responses and improve outcomes in …

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Measurement Of Volumetric Deformation, Strain Localization, And Shear Band Characterization During Triaxial Testing Using A Photogrammetry-Based Method, Sara Fayek, Xiong Zhang, Xiaolong Xia, Qingqing Fu, Jeffrey D. Cawlfield Jan 2023

Measurement Of Volumetric Deformation, Strain Localization, And Shear Band Characterization During Triaxial Testing Using A Photogrammetry-Based Method, Sara Fayek, Xiong Zhang, Xiaolong Xia, Qingqing Fu, Jeffrey D. Cawlfield

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Triaxial Testing Has Been Routinely Used as a Standard Laboratory Test that Allows Correct Determination of Soil Characteristics. Previously the Volumetric Strain of the Triaxial Specimen Was Considered to Be Uniformly Distributed Along with the Specimen during the Isotropic and Deviatoric Loading. Although This Assumption Might Hold True under Isotropic Loading, the Effects of Restrained Ends and Disturbance during the Procedures of Specimen Installation and Testing Can Cause Nonuniform Strains throughout the Whole Specimen. This Paper Investigates the Effects of Specimen Preparation and Misalignment on the Strain Uniformity Along with the Soil Specimen during Triaxial Testing. a Series of Consolidated …

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Point Density For Soil Specimen Volume Measurements In Image-Based Methods During Triaxial Testing, Sara Fayek, Xiong Zhang, Javad Galinmoghadam, Jeffrey D. Cawlfield Jan 2023

Point Density For Soil Specimen Volume Measurements In Image-Based Methods During Triaxial Testing, Sara Fayek, Xiong Zhang, Javad Galinmoghadam, Jeffrey D. Cawlfield

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Discrete Measurement Targets Were Frequently Utilized in Image-Based Methods on the Specimen's Surface to Monitor the Soil Specimen during Triaxial Testing. However, the Required Density of Measurement Targets that Should Be Used in Triaxial Testing to Achieve Highly Accurate Volume Measurement Has Not Been Investigated. to overcome This Limitation, This Paper Presents a Parametric Study to Determine the Optimum Target/point Densities to Be Utilized on the Triaxial Soil Specimen Surface to Achieve the Desired Level of Volume Measurement Accuracy in Image-Based Methods. LiDAR Scanning Was Applied to Establish the "Ground Truth" Volume of the Specimen. the Effects of Deformation and …

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Insights To Surfactant Huff-Puff Design In Carbonate Reservoirs Based On Machine Learning Modeling, Ya Yao, Yue Qiu, Yue Cui, Mingzhen Wei, Baojun Bai Jan 2023

Insights To Surfactant Huff-Puff Design In Carbonate Reservoirs Based On Machine Learning Modeling, Ya Yao, Yue Qiu, Yue Cui, Mingzhen Wei, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Surfactants could react with adsorbates on carbonate rock surface to alter wettability from oil-wetness to water-wetness, which is effective to enhance oil recovery. Surfactant huff-puff treatment is mostly applied for this purpose and the resulting surfactant performance is the outcome of complex interfacial processes. Currently, the effect of important parameters on surfactant performance is not completely reported and the contribution of each parameter to surfactant performance is hard to be quantified. Traditional methods to optimize surfactant performance are time-consuming and show strong dependency on extensive experiments. in this paper, we address these problems from machine learning (ML) perspectives. Several ML …

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Sedimentological And Geochemical Characterization Of A Varved Sediment Record From The Northern Neotropics, Edward Duarte, Jonathan Obrist-Farner, Susan R.H. Zimmerman, Erik T. Brown, Robert Brown Jan 2023

Sedimentological And Geochemical Characterization Of A Varved Sediment Record From The Northern Neotropics, Edward Duarte, Jonathan Obrist-Farner, Susan R.H. Zimmerman, Erik T. Brown, Robert Brown

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Annually resolved sedimentological records (including annual varves) can be used to develop precise chronologies for key climatic and tectonic events. Varved records, however, are most common in high latitude lakes, resulting in a spatial bias with respect to annually resolved records in tropical regions. Here we report on the sedimentology of two sediment cores from Lake Izabal, eastern Guatemala, that contain a well-preserved thinly laminated section spanning ca. 2200 years of the mid-Holocene. We integrate radiocarbon age-depth modeling, sedimentological observations, laminae counting, µX-ray fluorescence scanning, and multivariate statistical analyses to constrain the nature and chronology of the laminations. Our sedimentological …

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Laboratory Investigation Of Regained Rock Permeability Using High Viscosity Friction Reducer In Comparison To Linear Guar Fracture Fluids, Ghith Biheri, Abdulmohsin Imqam Jan 2023

Laboratory Investigation Of Regained Rock Permeability Using High Viscosity Friction Reducer In Comparison To Linear Guar Fracture Fluids, Ghith Biheri, Abdulmohsin Imqam

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Hydraulic fracturing is a method employed for extracting oil and gas from unconventional reservoirs by pumping a mixture of water, sand, and additives into the reservoirs to fracture oil formations. A high viscosity friction reducer (HVFR) based on polyacrylamide is a popular chemical that has been employed recently during hydraulic fracturing treatments to help transport proppant and to reduce friction. However, the use of HVFRs at high concentrations, especially in regions with high concentration levels of total dissolved solids (TDS), has raised concerns over the possibility of formation damage. In this research, a new type of HVFR was investigated for …

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Microcrystalline Dolomite In A Middle Permian Volcanic Lake: Insights On Primary Dolomite Formation In A Non-Evaporitic Environment, Xin Jiao, Yi Qun Liu, Wan Yang, Hong Li, Zi Yuan Meng, Min Ru Zhao, Zhe Xuan Li Jan 2023

Microcrystalline Dolomite In A Middle Permian Volcanic Lake: Insights On Primary Dolomite Formation In A Non-Evaporitic Environment, Xin Jiao, Yi Qun Liu, Wan Yang, Hong Li, Zi Yuan Meng, Min Ru Zhao, Zhe Xuan Li

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Lacustrine dolomite nucleation commonly occurs in modern and Neogene evaporitic alkaline lakes. As a result, ancient lacustrine microcrystalline dolomite has been conventionally interpreted to be formed in evaporitic environments. This study, however, suggests a non-evaporitic origin of dolomite precipitated in a volcanic–hydrothermal lake, where hydrothermal and volcanic processes interacted. The dolomite occurs in lacustrine fine-grained sedimentary rocks in the middle Permian Lucaogou Formation in the Santanghu intracontinental rift basin, north-west China. Dolostones are composed mainly of nano-sized to micron-sized dolomite with a euhedral to subhedral shape and a low degree of cation ordering, and are interlaminated and intercalated with tuffaceous …

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Repeatability Of Alkanolamines In Carbon Dioxide Capture After Mineralization, Titiwut Sirima Jan 2023

Repeatability Of Alkanolamines In Carbon Dioxide Capture After Mineralization, Titiwut Sirima

Chulalongkorn University Theses and Dissertations (Chula ETD)

The mineralization reaction between alkanolamines solution loaded with CO2 and calcium ions (Ca2+) produced calcium carbonate precipitate under an ambient condition, which reduced energy for thermal regeneration of alkanolamines solution. This work represented alkanolamines as monoethanolamine (MEA), diethanolamine (DEA), and triethanolamine (TEA). In addition, calcium chloride (CaCl2), calcium sulphate (CaSO4) and calcium hydroxide (Ca(OH)2) were used as calcium sources. Utilization of calcium hydroxide (Ca(OH)2) as a calcium source in the mineralization reaction resulted in the supernatant retaining its ability to capture carbon dioxide over 89%, which is similar to thermal regeneration. The mineral regeneration and the thermal regeneration can regenerate …

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Utility Optimization Via Multi-Section Heat Integration Approach For Multi-Period Operations, Ariyachai Silprasert Jan 2023

Utility Optimization Via Multi-Section Heat Integration Approach For Multi-Period Operations, Ariyachai Silprasert

Chulalongkorn University Theses and Dissertations (Chula ETD)

Heat Exchanger Network (HEN) optimization is essential for achieving utility conservation and minimizing the Total Annual Cost (TAC) by maximizing heat recovery between process streams. This study investigates on single and multi-section heat integration within a caprolactam (CPL) plant, conducted in collaboration with a petrochemical company. The investigation comprehensively addresses multi-period operations, considering production rate variability at 60%, 80%, and 100% loads. This variability is due to fluctuating operating conditions influenced by economic factors, as well as start-up and shut-down schedules. This work utilizes process simulation namely Aspen Plus and establishes HEN solutions using Aspen Energy Analyzer (AEA) and conventional …

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Techno-Economic Analysis Of Dimethyl Ether Production Via Direct Hydrogenation Of Co2, Boonyasit Farkham Jan 2023

Techno-Economic Analysis Of Dimethyl Ether Production Via Direct Hydrogenation Of Co2, Boonyasit Farkham

Chulalongkorn University Theses and Dissertations (Chula ETD)

To achieve carbon neutrality by 2050, alternative and sustainable fuels are receiving significant attention. One of the interesting options is dimethyl ether (DME), which can be synthesized from CO2. This research aimed to simulate DME production from CO2 by comparing indirect synthesis (two-step process) and direct synthesis (one-step process) methods. This study found that the one-step process had negative net CO2 emissions, with values of -1.16 tons CO2 per ton of DME. It also consumed less energy compared to that of the two-step process. This was because the amount of methanol generated in the two-step process was higher than in …

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วัสดุผสมขั้นสูงของไบโอชาร์และโครงสร้างโลหะอินทรีย์ (Mofs) สำหรับการเก็บไฮโดรเจน, แซมสัน บามิเดเล อาคินโดเย Jan 2023

วัสดุผสมขั้นสูงของไบโอชาร์และโครงสร้างโลหะอินทรีย์ (Mofs) สำหรับการเก็บไฮโดรเจน, แซมสัน บามิเดเล อาคินโดเย

Chulalongkorn University Theses and Dissertations (Chula ETD)

การพึ่งพาเชื้อเพลิงฟอสซิลในยุคอุตสาหกรรม โดยเฉพาะอย่างยิ่งสำหรับการขนส่ง ส่งผลให้การปล่อยก๊าซเรือนกระจก (GHG) เพิ่มขึ้นอย่างมาก ซึ่งมีส่วนทำให้เกิดการเปลี่ยนแปลงสภาพภูมิอากาศ การจัดการกับปัญหาสิ่งแวดล้อมนี้จำเป็นต้องมีแนวทางแก้ไขที่เป็นนวัตกรรมเพื่อลดการพึ่งพาเชื้อเพลิงแบบเดิมๆ การศึกษานี้มุ่งเน้นไปที่การพัฒนาวัสดุคอมโพสิตขั้นสูงที่ประกอบด้วยถ่านชีวภาพและกรอบโลหะ-อินทรีย์ (MOF) เพื่อการจัดเก็บไฮโดรเจนอย่างมีประสิทธิภาพ เพื่อลดการใช้เชื้อเพลิงฟอสซิลและผลกระทบต่อสิ่งแวดล้อม เราประเมินวัสดุแต่ละชนิด (ถ่านชีวภาพและ MOF) และส่วนประกอบของวัสดุเหล่านี้เกี่ยวกับความสมบูรณ์ของโครงสร้าง สัณฐานวิทยาของพื้นผิว ความพรุน การกระจายขนาดรูพรุน กลุ่มฟังก์ชันของพื้นผิว และความสามารถในการกักเก็บไฮโดรเจน ผลการศึกษาครั้งนี้สามารถปูทางไปสู่ความก้าวหน้าใหม่ๆ ในด้านวัสดุคอมโพสิตและกระทรวงการคลังเฉพาะทางสำหรับการจัดเก็บไฮโดรเจน ซึ่งส่งผลกระทบอย่างมีนัยสำคัญต่อความยั่งยืนและผลกระทบต่อสิ่งแวดล้อมของการขนส่งในอนาคต

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