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Full-Text Articles in Engineering

Benchmarking Of A Sco2 Heat Exchanger Flow Loop, David Velasco Apr 2024

Benchmarking Of A Sco2 Heat Exchanger Flow Loop, David Velasco

Doctoral Dissertations and Master's Theses

Heat transfer of supercritical carbon dioxide (sCO2) was studied experimentally by commissioning a sCO2 flow loop featuring a horizontal tube-in-tube counterflow heat exchanger with a circular cross section. The main objective was to establish experimental heat transfer research capabilities for sCO2 at Embry-Riddle Aeronautical University’s (ERAU) Thermal Science Lab. sCO2 experiences a drastic change in thermophysical properties near its critical point that results in unique heat transfer characteristics. The high pressures at which sCO2 exists make the large gradients in thermophysical and transport properties difficult to study, experimentally and numerically. However, understanding the heat transfer characteristics and thermophysical behavior of …


Machine Learning For Environmental Sustainability, Syeda Nyma Ferdous Jan 2024

Machine Learning For Environmental Sustainability, Syeda Nyma Ferdous

Graduate Theses, Dissertations, and Problem Reports

This research proposes a comprehensive approach to address pressing challenges in environmental sustainability, agricultural residue management, using machine learning based approaches. Machine learning (ML) techniques have emerged as powerful tools for addressing environmental sustainability challenges by facilitating the analysis and prediction of ecological phenomena, and optimization of resource management strategies. The study explores the synergies between environmental sustainability and machine learning to develop a framework that leverages artificial intelligence techniques covering a wide range of tasks including crop residue management, soil CO2 flux prediction, and forest carbon system prediction for sustainable development. The study analyze various ML models, such as, …


Hydrogen, Carbon Dioxide, And Methane Adsorption Potential On Jordanian Organic-Rich Source Rocks: Implications For Underground H2 Storage And Retrieval, Amer Alanazi, Hussein Rasool Abid, Muhammad Usman, Muhammad Ali, Alireza Keshavarz, Volker Vahrenkamp, Stefan Iglauer, Hussein Hoteit Aug 2023

Hydrogen, Carbon Dioxide, And Methane Adsorption Potential On Jordanian Organic-Rich Source Rocks: Implications For Underground H2 Storage And Retrieval, Amer Alanazi, Hussein Rasool Abid, Muhammad Usman, Muhammad Ali, Alireza Keshavarz, Volker Vahrenkamp, Stefan Iglauer, Hussein Hoteit

Research outputs 2022 to 2026

Hydrogen (H2) storage in geological formations offers a potential large-scale solution suitable for an industrial-scale hydrogen economy. However, the presence of organic residuals can significantly influence the H2 storage efficiency, as well as cushion gas performance, such as CO2 and CH4, injected to maintain healthy reservoir pressure. Thus, the H2 storage efficiency and cushion gas selectivity were thoroughly investigated in this work based on H2, CO2, and CH4 adsorption measurements using, for the first time, actual organic-rich carbonate-rich Jordanian source rock samples (TOC = 13 % to 18 …


Recent Developments In Timber Design & Its Impact On Carbon Emissions, Raquel Jackson Jun 2023

Recent Developments In Timber Design & Its Impact On Carbon Emissions, Raquel Jackson

Spectra Undergraduate Research Journal

This paper explores recent developments in timber building designs and its potential towards reducing carbon emissions. Carbon dioxide emissions are a growing issue worldwide as urbanization and industrialization continues to increase. The rising concentration of carbon dioxide emissions pose significant concerns towards public welfare and environmental health. Despite current methods to reduce greenhouse gasses, carbon emissions remain difficult to reduce from steel and concrete industries. Increasing timber use in building design is a possible solution. Increasing more timber in building design can help reduce carbon emissions due to the carbon-absorbing properties of the construction material. Timber as a construction material …


The Influence Of Environmental Tax And Technology On Different Air Pollution Emissions In Oecd Countries, Malak Ali Assaf May 2023

The Influence Of Environmental Tax And Technology On Different Air Pollution Emissions In Oecd Countries, Malak Ali Assaf

BAU Journal - Creative Sustainable Development

Although countries continuously employ taxation and technological measures to control air pollution in the Organization for Economic Co-operation and Development, the results of these practices should be evaluated to determine whether they reach their intended outcomes. This study used panel autoregressive distributed lag model to establish how environmental taxes and technology affects the emission of air pollutants (nitrogen oxides, Carbon dioxide, and particulate matter 2.5). Using secondary data present in the OECD Database and The World Bank, EViews panel was derived to create 3 model in which each of the three variables would be sufficiently explained by environmental tax, abatement …


Atmospheric Carbon Capture: A Review On Current Technologies And Analysis Of Energy Consumption For Various Direct Air Capture (Dac) Systems, Jennifer Perskin May 2023

Atmospheric Carbon Capture: A Review On Current Technologies And Analysis Of Energy Consumption For Various Direct Air Capture (Dac) Systems, Jennifer Perskin

Doctoral Dissertations and Master's Theses

Carbon dioxide (CO2) capture is a crucial approach to reducing greenhouse gases in the atmosphere to directly combat climate change. Major components of the technology to desublimate CO2 at cryogenic temperatures are mature and have the potential to be applied to build large Arctic/Antarctic direct-air CO2 capture plants. Pressure swing adsorption another gas separation technique used in industry today that can be modified for atmospheric carbon capture. The discussion of energy consumption for cryogenic and combined direct air capture systems is explored in this study. The investigation of precompression of atmospheric air for a direct-air capture …


Progress And Typical Case Analysis Of Demonstration Projects Of The Geological Sequestration And Utilization Of Co2, Liu Shiqi, Huang Fansheng, Du Ruibin, Chen Shiheng, Guan Yiting, Liu Yinghai, Wang Tao Apr 2023

Progress And Typical Case Analysis Of Demonstration Projects Of The Geological Sequestration And Utilization Of Co2, Liu Shiqi, Huang Fansheng, Du Ruibin, Chen Shiheng, Guan Yiting, Liu Yinghai, Wang Tao

Coal Geology & Exploration

The implementation of the geological sequestration and utilization of CO2 (CGSU) has considerable effects on CO2 emission reduction and is of great significance for the mitigation of global warming and the execution of the sustainable development strategy in China. Therefore, this study sorted the major methods for CGSU, made statistics of the global demonstration projects of CGSU, and primarily introduced the typical demonstration projects of CGSU in China. Furthermore, this study proposed prospects for the development trend of the CGSU technologies, which primarily include CO2 enhanced oil recovery (CO2-EOR), CO2 enhanced coalbed methane recovery …


Hydrogen Storage In Depleted Gas Reservoirs: A Comprehensive Review, Nasiru S. Muhammed, Md Bashirul Haq, Dhafer A. Al Shehri, Amir Al-Ahmed, Mohammad M. Rahman, Ehsan Zaman, Stefan Iglauer Apr 2023

Hydrogen Storage In Depleted Gas Reservoirs: A Comprehensive Review, Nasiru S. Muhammed, Md Bashirul Haq, Dhafer A. Al Shehri, Amir Al-Ahmed, Mohammad M. Rahman, Ehsan Zaman, Stefan Iglauer

Research outputs 2022 to 2026

Hydrogen future depends on large-scale storage, which can be provided by geological formations (such as caverns, aquifers, and depleted oil and gas reservoirs) to handle demand and supply changes, a typical hysteresis of most renewable energy sources. Amongst them, depleted natural gas reservoirs are the most cost-effective and secure solutions due to their wide geographic distribution, proven surface facilities, and less ambiguous site evaluation. They also require less cushion gas as the native residual gases serve as a buffer for pressure maintenance during storage. However, there is a lack of thorough understanding of this technology. This work aims to provide …


Computational Study Of C-C Coupling Reactions On Heterogeneous Catalysts, Md Saeedur Rahman Jan 2023

Computational Study Of C-C Coupling Reactions On Heterogeneous Catalysts, Md Saeedur Rahman

LSU Doctoral Dissertations

The utilization of carbon dioxide (CO2) in chemical production has attracted global research interest. Reacting CO2 with methane (CH4) removes these greenhouse gases from the atmosphere and turns both compounds into building blocks for organic compound synthesis. A commonly explored pathway involves dry reforming of methane (DRM), which reacts CH4 and CO2 to form syngas, a mixture of H2 and CO. Syngas is a widely used feedstock for synthesizing chemicals ranging from methanol to fuels via the Fischer-Tropsch (FT) process. However, DRM has a large positive ΔGº, which requires the …


Modeling The Production Of Microalgal Biomass In Large Water Resource Recovery Facilities And Its Processing Into Various Commodity Bioproducts, James Pierson, Gopi Raju Makkena, Sandeep Kumar, Vinod Kumar, Vivekanand Vivekanand, Hasan Husain, Muhammad Ayser, Venkatesh Balan Jan 2023

Modeling The Production Of Microalgal Biomass In Large Water Resource Recovery Facilities And Its Processing Into Various Commodity Bioproducts, James Pierson, Gopi Raju Makkena, Sandeep Kumar, Vinod Kumar, Vivekanand Vivekanand, Hasan Husain, Muhammad Ayser, Venkatesh Balan

Civil & Environmental Engineering Faculty Publications

Algae are capable of sequestering nutrients such as nitrates and phosphates from wastewater in the presence of sunlight and carbon dioxide (CO2) to build up their body mass and help combat climate change. In the current study, we carried out different case studies to estimate the volume of algal biomass that could be produced annually using the rotating algal biofilm (RAB) method in three large-scale water resource recovery facilities (WRRFs) in Texas: Fort Worth, Dallas, and Houston. We calculated the total amount of lipids, carbohydrates, and proteins that could be fractionated from the algal biomass while using the …


Food Waste Storage Gaseous Emissions Detection And Quantification Using Infrared Spectroscopy, Ryley A. Burton-Tauzer Jan 2023

Food Waste Storage Gaseous Emissions Detection And Quantification Using Infrared Spectroscopy, Ryley A. Burton-Tauzer

Cal Poly Humboldt theses and projects

A growing interest in sustainable waste management and the implementation of new policies have prompted a shift towards alternative resource recovery methods for organic waste, including food waste. To effectively assess alternative food waste treatment scenarios, it is important to evaluate the life cycle impacts associated with each scenario. The storage phase of food waste, encompassing its accumulation in kitchens, and storage in bins for collection and transportation, has been overlooked as a source of greenhouse gases in previous studies. This investigation aimed to identify the greenhouse gases emitted during the initial five-day period of low-oxygen storage. An open dynamic …


Artificial Neural Network For Predicting Heat Transfer Rates In Supercritical Carbon Dioxide, Vinusha Dasarla Giri Babu Dec 2022

Artificial Neural Network For Predicting Heat Transfer Rates In Supercritical Carbon Dioxide, Vinusha Dasarla Giri Babu

Doctoral Dissertations and Master's Theses

Supercritical carbon dioxide as a working fluid in a closed Brayton cycle is proving to be more efficient than a conventional steam-based Rankine engine. Understanding the heat transfer properties of supercritical fluids is important for the design of a working engine cycle. The thermophysical properties of supercritical fluids tend to vary non-linearly near the pseudo-critical region. Traditionally, empirical correlations are used to calculate the heat transfer coefficient. It has been shown in the literature and within our own studies that these correlations provide inaccurate predictions near the pseudo-critical line, where heat transfer may be deteriorated or enhanced, resulting from strong …


Correlating The Macrostructural Variations Of An Ion Gel With Its Carbon Dioxide Sorption Capacity, Tung Nguyen,, Mona Bavarian, Siamak Nejati Nov 2022

Correlating The Macrostructural Variations Of An Ion Gel With Its Carbon Dioxide Sorption Capacity, Tung Nguyen,, Mona Bavarian, Siamak Nejati

Department of Chemical and Biomolecular Engineering: Faculty Publications

We report on a direct correlation between the macroscale structural variations and the gas sorption capacities of an ion gel. Here, we chose 1-ethyl-3-methylimidazolium bis(trifluoromethyl sulfonyl)imide ([Emim][TF2N]) and poly(vinylidene fluoride)-co-hexafluoropropylene (PVDF-HFP) as the ionic liquid and host polymer, respectively. The CO2 sorption in the thin films of the IL-polymer was measured using the gravimetric method. The results of our experiment showed that the trend in CO2 uptake of these mixtures was nonlinearly correlated with the content of IL. Here, we highlight that the variations in the molecular structure of the polymers were the main reason behind …


Effect Of Bromoform And Linseed Oil On Greenhouse Gas Emissions From Stored Beef Manure, Andrew Ortiz Balsero, Mara Zelt, Amy Millmier Schmidt, Miguel Fudolig, Daniel N. Miller Jul 2022

Effect Of Bromoform And Linseed Oil On Greenhouse Gas Emissions From Stored Beef Manure, Andrew Ortiz Balsero, Mara Zelt, Amy Millmier Schmidt, Miguel Fudolig, Daniel N. Miller

Biological Systems Engineering: Papers and Publications

Emissions of carbon dioxide, methane, and nitrous oxide – potent greenhouse gases - from stored beef feedlot manure are a significant concern relative to climate change. Research on methane reduction strategies for enteric emissions has identified the application of organic additives, such as bromoform and linseed oil, to ruminant diets as potential solutions for reducing enteric emissions and pathogenic bacteria in excreted manure. The objective of this study was to determine the effect of bromoform and linseed oil on greenhouse gas emissions from beef feedlot manure, and on E. coli concentration in beef cattle manure, during a 5-week storage period. …


Calcium Ferrite As A Semiconductor For Microbially Assisted Photocatalytic Reduction Of Carbon Dioxide, Lauren King May 2022

Calcium Ferrite As A Semiconductor For Microbially Assisted Photocatalytic Reduction Of Carbon Dioxide, Lauren King

Honors Scholar Theses

The pressing issue of global climate change has been found to be attributed to the increasing concentration of greenhouse gases in the atmosphere, especially carbon dioxide. One mitigation idea to close the carbon loop is to utilize redox reactions and photocatalysis to reduce carbon dioxide to a useable fuel source, like methane or methanol. This thesis will study the possibility of using calcium ferrite as the semiconductor to perform photocatalytic reduction of carbon dioxide with the assistance of a microbial fuel cell, which will help minimize the energy required from sunlight photons. A calcium ferrite thin film was produced through …


A High-Performance Continuous-Flow Mea Reactor For Electroreduction Co2 To Formate, Pei-Xuan Liu, Lu-Wei Peng, Rui-Nan He, Lu-Lu Li, Jin-Li Qiao Jan 2022

A High-Performance Continuous-Flow Mea Reactor For Electroreduction Co2 To Formate, Pei-Xuan Liu, Lu-Wei Peng, Rui-Nan He, Lu-Lu Li, Jin-Li Qiao

Journal of Electrochemistry

The electrochemical carbon dioxide reduction reaction (CO2RR) is a promising approach to produce liquid fuels and industrial chemicals by utilizing intermittent renewable electricity for mitigating environmental problems. However, the traditional H-type reactor seriously limits the electrochemical performance of CO2RR due to the low CO2 solubility in electrolyte, and high ohmic resistance caused by the large distance between two electrodes, which is unbeneficial for industrial application. Herein, we demonstrated a high-performance continuous flow membranes electrode assembly (MEA) reactor based on a self-growing Cu/Sn bimetallic electrocatalyst in 0.5 mol·L-1 KHCO3 for converting CO2 to formate. …


Amine-Functionalized Interpenetrating Polymer Networks For Co2 Capture, James Wills Jan 2022

Amine-Functionalized Interpenetrating Polymer Networks For Co2 Capture, James Wills

Williams Honors College, Honors Research Projects

The research performed looked to advance the studies of vacuum swing absorption of Carbon Dioxide to help combat global climate change issues. The focus of the project was to create an anime-polymer sorbent that will weakly absorb and desorb CO2. The sorbent must be durable and be able to withstand multiple uses. The creation of a porous polymer matrix aided in the amines' ability to absorb CO2. Created samples underwent several qualitative and quantitative tests to determine their usefulness as an industrial sorbent. Infrared spectroscopy was used to study the effectiveness of the amine sorbents. Studying the changes in the …


Recent Advancements In Electrochemical Conversion Of Carbon Dioxide, Nandan Nag, Amit Kumar, Sumit Sharma, Sandeep Kumar, Amit K. Thakur Jan 2022

Recent Advancements In Electrochemical Conversion Of Carbon Dioxide, Nandan Nag, Amit Kumar, Sumit Sharma, Sandeep Kumar, Amit K. Thakur

Civil & Environmental Engineering Faculty Publications

Electrochemical reduction of carbon dioxide into eco-friendly and clean products is a promising approach to eradicate pollution. Although carbon dioxide emission is inhibited by the advent of renewable sources of energy, it is present in the atmosphere and needs to be cleaned. The reduction of carbon dioxide from atmospheric gases can be accomplished by its adsorption and subsequent transportation to electrolytic chambers, where it is reduced to hydrocarbons, organic acids or carbonates. This review focuses on developing a three compartment electrochemical cell to reduce carbon dioxide used as a catholyte. Various factors affecting the electrochemical reduction of carbon dioxide and …


Multi-Vendor And Multisite Evaluation Of Cerebrovascular Reactivity Mapping Using Hypercapnia Challenge, Peiying Liu, Dengrong Jiang, Marilyn Albert, Christopher E. Bauer, Arvind Caprihan, Brian T. Gold, Steven M. Greenberg, Karl G. Helmer, Kay Jann, Gregory A. Jicha, Pavel Rodriguez, Claudia L Satizabal, Sudha Seshadri, Herpreet Singh, Jeffrey F. Thompson, Danny J. J. Wang, Hanzhang Lu Nov 2021

Multi-Vendor And Multisite Evaluation Of Cerebrovascular Reactivity Mapping Using Hypercapnia Challenge, Peiying Liu, Dengrong Jiang, Marilyn Albert, Christopher E. Bauer, Arvind Caprihan, Brian T. Gold, Steven M. Greenberg, Karl G. Helmer, Kay Jann, Gregory A. Jicha, Pavel Rodriguez, Claudia L Satizabal, Sudha Seshadri, Herpreet Singh, Jeffrey F. Thompson, Danny J. J. Wang, Hanzhang Lu

Neuroscience Faculty Publications

Cerebrovascular reactivity (CVR), which measures the ability of cerebral blood vessels to dilate or constrict in response to vasoactive stimuli such as CO2 inhalation, is an important index of the brain's vascular health. Quantification of CVR using BOLD MRI with hypercapnia challenge has shown great promises in research and clinical studies. However, in order for it to be used as a potential imaging biomarker in large-scale and multi-site studies, the reliability of CO2-CVR quantification across different MRI acquisition platforms and researchers/raters must be examined. The goal of this report from the MarkVCID small vessel disease biomarkers consortium is to evaluate …


Date Palm Waste Pyrolysis Into Biochar For Carbon Dioxide Adsorption, Imen Ben Salem, Mariam Badawi Saleh, Jibran Iqbal, Maisa El Gamal, Suhaib Hameed Sep 2021

Date Palm Waste Pyrolysis Into Biochar For Carbon Dioxide Adsorption, Imen Ben Salem, Mariam Badawi Saleh, Jibran Iqbal, Maisa El Gamal, Suhaib Hameed

All Works

Mitigation of CO2 is a very popular research currently, it is ultimately beneficial to find new ways that are sustainable, low cost and gas emission friendly. Therefore, with biochar’s characteristics and properties it has great potential to be used as a CO2 capture and storage media. The objectives of reducing palm waste by using the low-cost, sustainable method for reducing and storing CO2, characterize the DPL biochar through FTIR, XRD, SEM, EDX, and then evaluate the efficiency of the date palm leaf waste biochar in adsorbing CO2 through the Gas–Solid analyzer technology. Date palm leaf was set in pyrolysis process …


Review On Carbon Dioxide Utilization For Cycloaddition Of Epoxides By Ionic Liquid-Modified Hybrid Catalysts: Effect Of Influential Parameters And Mechanisms Insight, Jimmy Nelson Appaturi, Rajabathar. Jothi Ramalingam, Muthu Kumaran Gnanamani, Govindasami Periyasami, Prabhakarn Arunachalam, Rohana Adnan, Farook Adam, Mohammed D. Wasmiah, Hamad A. Al‐Lohedan Jan 2021

Review On Carbon Dioxide Utilization For Cycloaddition Of Epoxides By Ionic Liquid-Modified Hybrid Catalysts: Effect Of Influential Parameters And Mechanisms Insight, Jimmy Nelson Appaturi, Rajabathar. Jothi Ramalingam, Muthu Kumaran Gnanamani, Govindasami Periyasami, Prabhakarn Arunachalam, Rohana Adnan, Farook Adam, Mohammed D. Wasmiah, Hamad A. Al‐Lohedan

Center for Applied Energy Research Faculty and Staff Publications

The storage, utilization, and control of the greenhouse (CO2) gas is a topic of interest for researchers in academia and society. The present review article is dedicating to cover the overall role of ionic liquid-modified hybrid materials in cycloaddition reactions. Special emphasis is on the synthesis of various cyclic carbonate using ionic liquid-based modified catalysts. Catalytic activity studies have discussed with respect to process conditions and their effects on conversion and product selectivity for the reaction of cycloaddition of CO2 with styrene oxide. The reaction temperature and the partial pressure of CO2 have found to play …


Synthesis And Catalytic Properties Of Metal-Organic Frameworks Mimicking Carbonic Anhydrase, Longji Li Jan 2021

Synthesis And Catalytic Properties Of Metal-Organic Frameworks Mimicking Carbonic Anhydrase, Longji Li

Mahurin Honors College Capstone Experience/Thesis Projects

The natural enzyme carbonic anhydrase has gained attention in recent years for its ability to catalyze the interconversion of aqueous carbon dioxide (CO2) and bicarbonate. However, it lacks the efficiency to qualify practical usage on a large scale due to its inherent deficiency and fragile nature. On the other hand, its active center can be used as an ideal model for the design of novel catalytic materials targeting carbon dioxide capture and sequestration. This study focused on the synthesis of a zinc-based metal-organic framework (Zn-MOF-1) mimicking the carbonic anhydrase using the solvothermal method. Important properties such as catalytic …


Carbon Capture And Utilization, Sriram Valluri Jan 2021

Carbon Capture And Utilization, Sriram Valluri

Dissertations, Master's Theses and Master's Reports

As the world moves towards clean energy initiative, carbon capture and utilization technologies are key to achieving net zero emissions. CO2 capture with amines has many disadvantages and cannot be applied to commercial power plants. The current manuscript will address this issue as well as a solution that involves the use of low-cost alkali absorbent CO2 capture solutions, combined with an electrochemical regeneration method that uses the least amount of energy available for capture and regeneration. This research will also further address the issue of how to deal with the captured CO2. Several viable storage and utilization methods have …


New Horizons For Processing And Utilizing Red Mud, M. Archambo Jan 2021

New Horizons For Processing And Utilizing Red Mud, M. Archambo

Dissertations, Master's Theses and Master's Reports

Red mud is an industrial slurry waste that is produced as a byproduct of the Bayer process for alumina. The waste is generated in large quantities, up to a ratio of 2:1 against the valued product alumina. Red mud exhibits many chemical and physical properties that categorize it as a hazardous material. Due to the addition of sodium hydroxide in processing, the pH is typically at values close to 13. Small particle size discourages separation from water for disposal, so drying red mud happens over many years.

The pH of red mud can be reduced with inexpensive reagents. Carbon dioxide …


A Model For The Anodic Carbonization Of Alkaline Polymer Electrolyte Fuel Cells, Qi-Hao Li, Ying-Ming Wang, Hua-Long Ma, Li Xiao, Gong-Wei Wang, Jun-Tao Lu, Lin Zhuang Oct 2020

A Model For The Anodic Carbonization Of Alkaline Polymer Electrolyte Fuel Cells, Qi-Hao Li, Ying-Ming Wang, Hua-Long Ma, Li Xiao, Gong-Wei Wang, Jun-Tao Lu, Lin Zhuang

Journal of Electrochemistry

The alkaline polymer electrolyte fuel cell (APEFC) has made appreciable progress in recent years but is still suffering performance loss during discharge with air as the oxidant. Several theories have been suggested to interpret the loss. However, efforts are still needed to reach a clear quantitative understanding. Based on the major experimental findings in combination with thermodynamics and kinetics of the reactions involved in the anode, this paper presents a model featuring layered carbonization in the anode and relevant grouped equations. The simulation results generated from the latter are compared with experiments, and possible principles to suppress the performance loss …


Volume Frequency Response Method For Determining Mass Transfer Mechanisms Of O2 In Carbon Molecular Sieve 3k172, Olivia Smithson Oct 2020

Volume Frequency Response Method For Determining Mass Transfer Mechanisms Of O2 In Carbon Molecular Sieve 3k172, Olivia Smithson

Theses and Dissertations

Carbon molecular sieves (CMS) have grown more desirable over the years as an adsorbent for industrial separation processes as CMS technology has advanced. CMS is commonly used in nitrogen inerting (i.e, oxygen removal from air), carbon dioxide removal from methane and oxygen purification. However, knowledge of the dynamic behavior of these gases on CMS is needed to design and operate efficient and effective separation processes. For this reason, the mass transfer resistances within the micropore at both low and high frequencies were characterized using frequency response, COMSOL Multiphysics modeling, and MATLAB optimization , because frequency response methods have demonstrated the …


Recent Progress On Enhancing Effect Of Nanosized Metals For Electrochemical Co2 Reduction, Yu-Ning Zhang, Dong-Fang Niu, Shuo-Zhen Hu, Xin-Sheng Zhang Aug 2020

Recent Progress On Enhancing Effect Of Nanosized Metals For Electrochemical Co2 Reduction, Yu-Ning Zhang, Dong-Fang Niu, Shuo-Zhen Hu, Xin-Sheng Zhang

Journal of Electrochemistry

The electrochemical conversion of CO2 to chemical raw material for further utilization shows promising future to alleviate global warming and realize carbon cycle in nature, which is of great significance to the green chemistry and sustainable development. This review briefly introduces the advantages of CO2 electrochemical reduction (CO2ER) and its basic reaction principles, and summarizes the recent progress in a series of activity enhancement strategies based on nanosized metal catalysts. The influences of alloy effect, interface engineering, synergistic effect, surface defect engineering and support effect on the catalytic performance of nanosized metals for CO2ER …


The Temporal And Spatial Dynamics Of Fluvial Carbon Cycling In Irish Blanket Peatland Pools And Soils, Mariya Radomski Jan 2020

The Temporal And Spatial Dynamics Of Fluvial Carbon Cycling In Irish Blanket Peatland Pools And Soils, Mariya Radomski

Doctoral

Blanket peatlands in Ireland are reservoirs of organic matter and have effects on carbon dioxide (CO2) flux regulation. Data on dissolved CO2 in Ireland is limited. In blanket peatlands, the drainage systems are well connected with pools, hummocks and lawns and this connectivity leads to significant variations in outflows of carbon. The excess carbon dioxide in blanket peatlands could originate from soil organic matter decomposition. Dissolved CO2 could be transported into pools via surface run-off and lateral throughflow. Peatland pools are typically supersaturated in CO2. As part of a project described in this thesis, the role of spatial and seasonal …


Impact Of Cognitive Tasks On Co2 And Isoprene Emissions From Humans, Elliott T. Gall, Asit Kumar Mishra, Jiayu Li, Stefano Schiavon, Aurelie Laguerre Jan 2020

Impact Of Cognitive Tasks On Co2 And Isoprene Emissions From Humans, Elliott T. Gall, Asit Kumar Mishra, Jiayu Li, Stefano Schiavon, Aurelie Laguerre

Mechanical and Materials Engineering Faculty Publications and Presentations

The human body emits a wide range of chemicals, including CO2 and isoprene. To examine the impact of cognitive tasks on human emission rates of CO2 and isoprene, we conducted an across-subject, counterbalanced study in a controlled chamber involving 16 adults. The chamber replicated an office environment. In groups of four, participants engaged in 30 min each of cognitive tasks (stressed activity) and watching nature documentaries (relaxed activity). Measured biomarkers indicated higher stress levels were achieved during the stressed activity. Per-person CO2 emission rates were greater for stressed than relaxed activity (30.3 ± 2.1 vs 27.0 ± 1.7 g/h/p, p …


Statuses, Challenges And Strategies In The Development Of Low-Temperature Carbon Dioxide Electroreduction Technology, Xu-Rui Zhang, Xiao-Lin Shao, Jin Yi, Yu-Yu Liu, Jiu-Jun Zhang Aug 2019

Statuses, Challenges And Strategies In The Development Of Low-Temperature Carbon Dioxide Electroreduction Technology, Xu-Rui Zhang, Xiao-Lin Shao, Jin Yi, Yu-Yu Liu, Jiu-Jun Zhang

Journal of Electrochemistry

Low-temperature carbon dioxide (CO2) electrochemical reduction technology is a hotspot for research and development in recent years as a way to reduce the negative impact of CO2 on the environment and to generate energy storage through converting electricity to low-carbon fuels. Although basic research on catalyst activity, product selectivity, and reaction mechanism has been widely reported, the design and practicality of catalytic stability and corresponding electrochemical reactor systems have not been given sufficient attention and systematic development. In this paper, two important factors affecting the development of CO2 electrochemical reduction technology in low temperature aqueous solution …