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Effects Of Mars Global Simulant (Mgs-1) On Growth And Physiology Of Sweet Potato: A Space Model Plant, Karthik Chinnannan, Prapooja Somagattu, Hyndavi Yammanuru, Padma Nimmakayala, Manohar Chakrabarti, Umesh K. Reddy Dec 2023

Effects Of Mars Global Simulant (Mgs-1) On Growth And Physiology Of Sweet Potato: A Space Model Plant, Karthik Chinnannan, Prapooja Somagattu, Hyndavi Yammanuru, Padma Nimmakayala, Manohar Chakrabarti, Umesh K. Reddy

School of Integrative Biological and Chemical Sciences Faculty Publications and Presentations

Growing food autonomously on Mars is challenging due to the Martian soil's low nutrient content and high salinity. Understanding how plants adapt and evaluating their nutritional attributes are pivotal for sustained Mars missions. This research delves into the regeneration, stress tolerance, and dietary metrics of sweet potato (Ipomoea batatas) across different Mars Global Simulant (MGS-1) concentrations (0, 25, 50, and 75%). In our greenhouse experiment, 75% MGS-1 concentration significantly inhibited sweet potato growth, storage root biomass, and chlorophyll content. This concentration also elevated the plant tissues' H2O2, proline, and ascorbic acid levels. Higher MGS-1 exposures (50 and 75%) …


Biochar Reduces The Pupation And Eclosion Of A Specialist (Manduca Sexta) And A Generalist Pest (Spodoptera Frugiperda), Nischal Wagle Jul 2023

Biochar Reduces The Pupation And Eclosion Of A Specialist (Manduca Sexta) And A Generalist Pest (Spodoptera Frugiperda), Nischal Wagle

Theses and Dissertations

Chapter 1: This chapter incorporates detailed information about the biochar concept, its production, composition, and properties, harmful arthropods and their damage, the effect of soil on the arthropod community, and the application of biochar on arthropod control.

Chapter 2: The comprehensive lab experiment was conducted with modified pupation media enriched with walnut shell biochar (Chapter II) to evaluate the effects of biochar on the pupation and eclosion success rates of a specialist (Manduca sexta) and a generalist pest (Spodoptera frugiperda). We found that the biochar treatment led to a significant reduction in pupal mass, adult mass, adult wingspan, body length, …


Comparative Analysis Of Soil Properties, Microbial Community Composition, And Yield Responses To Cover Crops In Different Ecoregions Of South Texas, Daphne Zapsas Jul 2023

Comparative Analysis Of Soil Properties, Microbial Community Composition, And Yield Responses To Cover Crops In Different Ecoregions Of South Texas, Daphne Zapsas

Theses and Dissertations

Comprehensive understanding of soil properties, their interdependencies, and the effects of management practices is crucial for designing sustainable agricultural strategies. By adopting site-specific and need-based practices that enhance soil health, farmers can optimize crop growth, increase yield, and contribute to long-term environmental sustainability. Cover crops have been recognized for enhancing soil fertility, promoting microbial activity, and increasing organic matter content. However, while their effectiveness is well documented in temperate regions with readily available water, their impact in water limited systems in subtropical regions remains mixed. The aim of this study is to assess soil conditions in four different farms across …


Health And Safety Effects Of Airborne Soil Dust In The Americas And Beyond, Daniel Q. Tong, Thomas E. Gill, William A. Sprigg, Robert Scott Van Pelt, Alexander Baklanov, Bridget Marie Barker, Jesse E. Bell, Juan Castillo, Santiago Gassó, Cassandra Gaston, Amit U. Raysoni Mar 2023

Health And Safety Effects Of Airborne Soil Dust In The Americas And Beyond, Daniel Q. Tong, Thomas E. Gill, William A. Sprigg, Robert Scott Van Pelt, Alexander Baklanov, Bridget Marie Barker, Jesse E. Bell, Juan Castillo, Santiago Gassó, Cassandra Gaston, Amit U. Raysoni

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Risks associated with dust hazards are often underappreciated, a gap between the knowledge pool and public awareness that can be costly for impacted communities. This study reviews the emission sources and chemical, physical, and biological characteristics of airborne soil particles (dust) and their effects on human and environmental health and safety in the Pan-American region. American dust originates from both local sources (western United States, northern Mexico, Peru, Bolivia, Chile, and Argentina) and long-range transport from Africa and Asia. Dust properties, as well as the trends and interactions with criteria air pollutants, are summarized. Human exposure to dust is associated …


Grapefruit Peel Biochar Applications For Immobilizing Copper And Lead In Soil, Michael Alfredo Navarro Dec 2022

Grapefruit Peel Biochar Applications For Immobilizing Copper And Lead In Soil, Michael Alfredo Navarro

Theses and Dissertations

This study investigated the efficacy of grapefruit peel (GP) derived biochar materials (two pyrolysis temperatures 450°C and 800°C) as a potential adsorbent to immobilize heavy metal (copper and lead) in a local sandy loam clay soil. A batch adsorption test with heavy metal concentrations at 50 mg L-1, and 100 mg L-1 revealed that soil itself had the highest immobilization percentage compared to the GP biochars. A soil column experiment was conducted to determine how much the GP biochar samples and the tested soil will exhibit adsorptive characteristics for heavy metals when 50 ml of 50 mg L-1 copper or …


Constructing An Intelligent Model Based On Support Vector Regression To Simulate The Solubility Of Drugs In Polymeric Media, Sait Senceroglu, Mohamed Arselene Ayari, Tahereh Rezaei, Fardad Faress, Amith Khandakar, Muhammad E. H. Chowdhury, Zanko Hassan Jawhar Nov 2022

Constructing An Intelligent Model Based On Support Vector Regression To Simulate The Solubility Of Drugs In Polymeric Media, Sait Senceroglu, Mohamed Arselene Ayari, Tahereh Rezaei, Fardad Faress, Amith Khandakar, Muhammad E. H. Chowdhury, Zanko Hassan Jawhar

International Business and Entrepreneurship Faculty Publications and Presentations

This study constructs a machine learning method to simultaneously analyze the thermodynamic behavior of many polymer–drug systems. The solubility temperature of Acetaminophen, Celecoxib, Chloramphenicol, D-Mannitol, Felodipine, Ibuprofen, Ibuprofen Sodium, Indomethacin, Itraconazole, Naproxen, Nifedipine, Paracetamol, Sulfadiazine, Sulfadimidine, Sulfamerazine, and Sulfathiazole in 1,3-bis[2-pyrrolidone-1-yl] butane, Polyvinyl Acetate, Polyvinylpyrrolidone (PVP), PVP K12, PVP K15, PVP K17, PVP K25, PVP/VA, PVP/VA 335, PVP/VA 535, PVP/VA 635, PVP/VA 735, Soluplus analyzes from a modeling perspective. The least-squares support vector regression (LS-SVR) designs to approximate the solubility temperature of drugs in polymers from polymer and drug types and drug loading in polymers. The structure of this machine …


Introducing A Linear Empirical Correlation For Predicting The Mass Heat Capacity Of Biomaterials, Reza Iranmanesh, Afham Pourahmad, Fardad Faress, Sevil Tutunchian, Mohammad Amin Ariana, Hamed Sadeqi, Saleh Hosseini, Falah Alobaid, Babak Aghel Oct 2022

Introducing A Linear Empirical Correlation For Predicting The Mass Heat Capacity Of Biomaterials, Reza Iranmanesh, Afham Pourahmad, Fardad Faress, Sevil Tutunchian, Mohammad Amin Ariana, Hamed Sadeqi, Saleh Hosseini, Falah Alobaid, Babak Aghel

International Business and Entrepreneurship Faculty Publications and Presentations

This study correlated biomass heat capacity (Cp) with the chemistry (sulfur and ash content), crystallinity index, and temperature of various samples. A five-parameter linear correlation predicted 576 biomass Cp samples from four different origins with the absolute average relative deviation (AARD%) of ~1.1%. The proportional reduction in error (REE) approved that ash and sulfur contents only enlarge the correlation and have little effect on the accuracy. Furthermore, the REE showed that the temperature effect on biomass heat capacity was stronger than on the crystallinity index. Consequently, a new three-parameter correlation utilizing crystallinity index and temperature was developed. This model was …


Upcycling Mask Waste To Carbon Capture Sorbents: A Combined Experimental And Computational Study, Mark Robertson, Alejandro Guillen Obando, Bianca Nunez, Haoyuan Chen, Zhe Qiang Aug 2022

Upcycling Mask Waste To Carbon Capture Sorbents: A Combined Experimental And Computational Study, Mark Robertson, Alejandro Guillen Obando, Bianca Nunez, Haoyuan Chen, Zhe Qiang

Chemistry Faculty Publications and Presentations

Massive plastic pollution and grand scale emission of CO2 into the atmosphere represent two major and deeply connected societal challenges, which can have adverse impacts on climate, human health, and marine ecosystems. In particular, the COVID-19 pandemic led to substantially increased production, use, and discarding of disposable masks, a problem that requires urgent and effective technological solutions to mitigate their negative environmental impacts. Furthermore, over the years significant research efforts have sought to address the challenges of plastic waste and CO2 emission, such as development of chemical upcycling methods and low-cost CO2 capture sorbents at scale, respectively. In this work, …


Iron And Magnesium Impregnation Of Avocado Seed Biochar For Aqueous Phosphate Removal, James Ji Hoon Kang, Jason Parsons, Sampath Gunukula, Dat T. Tran Jul 2022

Iron And Magnesium Impregnation Of Avocado Seed Biochar For Aqueous Phosphate Removal, James Ji Hoon Kang, Jason Parsons, Sampath Gunukula, Dat T. Tran

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

There has been increasing interest in using biochar for nutrient removal from water, and its application for anionic nutrient removal such as in phosphate (PO43) necessitates surface modifications of raw biochar. This study produced avocado seed biochar (AB), impregnated Fe- or Mg-(hydr)oxide onto biochar (post-pyrolysis), and tested their performance for aqueous phosphate removal. The Fe- or Mg-loaded biochar was prepared in either high (1:8 of biochar to metal salt in terms of mass ratio) or low (1:2) loading rates via the co-precipitation method. A total of 5 biochar materials (unmodified AB, AB + High Fe, AB …


Biomass Residues Improve Soil Chemical And Biological Properties Reestablishing Native Species In An Exposed Subsoil In Brazilian Cerrado, Thaís Soto Boni, Engil Isadora Pujol Pereira, Adriana Avelino Santos, Ana Maria Rodrigues Cassiolato, Kátia Luciene Maltoni Jun 2022

Biomass Residues Improve Soil Chemical And Biological Properties Reestablishing Native Species In An Exposed Subsoil In Brazilian Cerrado, Thaís Soto Boni, Engil Isadora Pujol Pereira, Adriana Avelino Santos, Ana Maria Rodrigues Cassiolato, Kátia Luciene Maltoni

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Revegetation of exposed sub-soil, while a desirable strategy in the recovery processes, often fails due to extreme soil chemical properties, such as low organic matter and pH levels inhospitable to biological activities such as nutrients cycling and plant establishment. This is the case for approximately 800 ha of the Cerrado biome in Brazil, where erecting the embankment of a hydroelectric dam in the 1960’s stripped vegetation, soil, and subsoil layers thereby distorting the soil properties. This work evaluates the effectiveness of restoration management (RM) treatments, to restore the soil quality, including biological activity and chemical attributes. In a factorial scheme, …


Effects Of Biochar Production Methods And Biomass Types On Lead Removal From Aqueous Solution, Paola Granados, Sergio Mireles, Engil Isadora Pujol Pereira, Chu-Lin Cheng, James Jihoon Kang May 2022

Effects Of Biochar Production Methods And Biomass Types On Lead Removal From Aqueous Solution, Paola Granados, Sergio Mireles, Engil Isadora Pujol Pereira, Chu-Lin Cheng, James Jihoon Kang

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Biochar has proven its potential in removing heavy metal ions from water. The objective of this study was to evaluate locally obtained biomass feedstocks for biochar production and their efficiency as a sorbent for aqueous lead (Pb2+) removal. The biomass feedstocks consisted of avocado seed, avocado peel, grapefruit peel, and brown seaweed, which represent agricultural and marine biomasses. The biochar materials were produced in two different methods: (1) a laboratory tube furnace at 300 °C and (2) a Do-It-Yourself (DIY) biochar maker, “BioCharlie Log”. The biochars were characterized for selected physicochemical properties, and batch adsorption tests with 10 …


Uptake Analysis Of As(Iii) And As(V) By Cassia Fistula Seedlings, Valeria Velazquez Aug 2021

Uptake Analysis Of As(Iii) And As(V) By Cassia Fistula Seedlings, Valeria Velazquez

Theses and Dissertations

The natural and anthropogenic contamination of water by arsenic has become a major concern to the environment and public health. Phytoremediation is an attractive alternative to ecologically friendly remove contaminants at a potential high efficiency and low cost. Absorption of As(III) and As(V) was evaluated by the measuring the content of arsenic in the roots, leaves and stems Cassia fistula grown under controlled conditions in a hydroponics system. After seeds were germinated, the plants were grown in Hoagland nutrient solution individually supplemented with 1, 2, 5 ppm of As(III) and As(V). After two weeks of exposure, samples of leaves, roots, …


Biochar Applications To The Remediation Of Lead And Polychlorinated Biphenyl Contaminated Water, Victory Itua Igberase Aug 2021

Biochar Applications To The Remediation Of Lead And Polychlorinated Biphenyl Contaminated Water, Victory Itua Igberase

Theses and Dissertations

This study investigated the performance of biochar materials as adsorbents to remove Pb and polychlorinated biphenyl (PCB) in aqueous solutions. Batch adsorption and column experiment packed with biochar and geomaterials (pumice) in 1:1 volume ratio was evaluated to address the efficacy of biochar in removing Pb while only batch adsorption was employed for PCB removal with biochar materials. Overall, PT biochars performed the best (42–53 mg g−1) followed by BE biochars (10–32 mg g−1) and AB biochars (17–27 mg g−1) while high temperature biochars were favored in terms of maximum Pb adsorption capacity. Column Pb breakthrough showed similar results, with …


Hydraulic Characterization Of Porous Media For Remediation Applications In Geo-Environmental Engineering: Laboratory Experiment And Numerical Modeling, Syed Istiyak Ahmed Jul 2021

Hydraulic Characterization Of Porous Media For Remediation Applications In Geo-Environmental Engineering: Laboratory Experiment And Numerical Modeling, Syed Istiyak Ahmed

Theses and Dissertations

Hydraulic properties of porous media are very important characters for various geotechnical and geo-environmental applications. In this study, multi-step outflow experiments and numerical modeling were performed for homogeneous and layered column conditions with fine to coarse sands to investigate water flow mechanisms and better predict water flow and solute transport with the van Genuchten-Mualem (VGM) hydraulic model. Inversed modeling under HYDRUS-1D was performed to estimate six VGM soil hydraulic parameters. Forward modeling was conducted to evaluate the impacts of VGM hydraulic parameters along with saturated hydraulic conductivity to solute transport. Scaling effects such as column length, time, and chemical parameters …


Unravelling The Role Of Pgpr "Pseudomonas Fluorescens" In Semi- Arid Soils Of The Rio Grande Valley, Mandip Tamang May 2021

Unravelling The Role Of Pgpr "Pseudomonas Fluorescens" In Semi- Arid Soils Of The Rio Grande Valley, Mandip Tamang

Theses and Dissertations

Chapter 1: In this chapter, we have provided a review on the components of rhizosphere engineering and the potential use of PGPR and its challenges to serve as an efficient component for sustainable agriculture.

Chapter 2: In this chapter, we isolated 35 different strains of a PGPR, Pseudmonas fluorescens and characterized various plant growth promoting traits such as production of ammonia, protease, Indole acitic acid (IAA), 1-aminocyclopropane-1-carboxylate deaminase (ACC) deaminase, ammonia, hydrogen cyanide (HCN), and souliblization of zinc and phosphate.

Chapter 3: In this chapter, we tested the influence of plant beneficial soil microbe, P. fluorescens, on the growth and …


Compost And Biochar To Promote Soil Biological Activities Under Sweet Potatoes Cultivation In A Subtropical Semiarid Region, Josabeth Navarro, Jahdiel Salazar, James Jihoon Kang, Jason Parsons, Chu-Lin Cheng, Alexandria Castillo, Engil Isadora Pujol Pereira Nov 2020

Compost And Biochar To Promote Soil Biological Activities Under Sweet Potatoes Cultivation In A Subtropical Semiarid Region, Josabeth Navarro, Jahdiel Salazar, James Jihoon Kang, Jason Parsons, Chu-Lin Cheng, Alexandria Castillo, Engil Isadora Pujol Pereira

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

South Texas is located in a subtropical semiarid climate, and due to high temperature and irregular precipitation, farmers opt to leave their fields fallow during the summer months jeopardizing overall soil health. We evaluated whether sweet potato (Ipomoea batatas) cultivation coupled with drip irrigation could restore soil biological activities compared with bare fallow. Additionally, because sweet potatoes have high demand of soil nutrients, especially potassium (K), we evaluated the nutrient supply of locally sourced soil amendments. Sweet potato was cultivated during summer 2018 in McAllen, Texas, under control (no fertilizer), NPK (synthetic fertilizer), RC (yard-waste compost), and AC (compost produced …


Biochar Enhances Nitrous Oxide Reduction In Acidic But Not In Near-Neutral Ph Soil, Engil Isadora Pujol Pereira, Jerome Lechot, Rafaela Feola Conz, Abmael Da Silva Cardoso, Johan Six Oct 2019

Biochar Enhances Nitrous Oxide Reduction In Acidic But Not In Near-Neutral Ph Soil, Engil Isadora Pujol Pereira, Jerome Lechot, Rafaela Feola Conz, Abmael Da Silva Cardoso, Johan Six

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

We quantified nitrous oxide (N2O) fluxes and total denitrification (N2O + N2) in an acidic (Ferralsol) and a near-neutral pH soil (Cambisol) to determine whether biochar’s alkalinization effect could be the mechanism inducing potential reductions in N2O fluxes. In Ferralsol, decreases in N2O emissions and in the N2O to N2O + N2 ratio were observed in both biochar and lime treatments. In Cambisol, neither biochar nor lime decreased N2O emissions, despite significantly increasing soil pH. The abundance and community structure of nosZ gene-bearing microorganisms indicated that gene abundances did not explain biochar effects, but a higher diversity of nosZ gene-bearing …


Sand And Pumice Filter Amended With Activated Carbon And Biochar For Phosphorus Retention, James Jihoon Kang, Marissa Davila, Sergio Mireles, Jungseok Ho Aug 2019

Sand And Pumice Filter Amended With Activated Carbon And Biochar For Phosphorus Retention, James Jihoon Kang, Marissa Davila, Sergio Mireles, Jungseok Ho

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Phosphorus (P) loss via stormwater runoff is a water quality concern. The objective of this study was to investigate two commercial biochars relative to an activated carbon as an additive to geomedia (sand and pumice) for P removal. The batch adsorption experiment was conducted to assess P sorption of the geomedia and carbon materials while the leaching experiment was conducted in sand and pumice columns amended with carbon materials (5 % by weight). The batch adsorption test revealed that only activated carbon showed an appreciable P adsorption up to 19 %. Tested biochar materials showed no adsorption capacity for P …


Sweet Potato: A Potentially Profitable Summer Crop For South Texas Organic Farmers To Enhance Soil Biological Activity And Nutrient Release, Jahdiel Salazar, Josabeth Navarro, Jihoon Kang, Engil Isadora Pujol Pereira Jan 2019

Sweet Potato: A Potentially Profitable Summer Crop For South Texas Organic Farmers To Enhance Soil Biological Activity And Nutrient Release, Jahdiel Salazar, Josabeth Navarro, Jihoon Kang, Engil Isadora Pujol Pereira

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

No abstract provided.


Arabidopsis Thaliana Transformed With Streptanthus Farnsworthianus Metal Tolerance Protein 1 (Sfmtp1) Or The Native A. Thaliana Metal Tolerance Protein 1 ( Atmtp1) Cdna And The Effects On Sod Enzyme Activity Upon Nickel Treatment, Selina Urbina Fernandez Dec 2018

Arabidopsis Thaliana Transformed With Streptanthus Farnsworthianus Metal Tolerance Protein 1 (Sfmtp1) Or The Native A. Thaliana Metal Tolerance Protein 1 ( Atmtp1) Cdna And The Effects On Sod Enzyme Activity Upon Nickel Treatment, Selina Urbina Fernandez

Theses and Dissertations

Superoxide Dismutase enzyme activity was analyzed in transgenic Arabidopsis thaliana, a non-accumulator weed plant species of the Brassicaceae family, that was transformed with Streptanthus farnsworthianus Metal Tolerance Protein1 (SfMTP1) or A. thaliana Metal Tolerance Protein 1 (AtMTP1 ). The transgenic A. thaliana was exposed to a 12 day treatment of 100 ?M Nickel Acetate in 1/10 X Hoaglands solution in hydroponics. Analysis of Super Oxide Dismutase activity determined that transgenic A. thaliana transformed with the AtMTP1 cDNA and treated with 100 µM Nickel showed a significant increase in Super Oxide Dismutase activity compared to A. thaliana …


Thermodynamic And Kinetic Study Of The Removal Of Cu2+ And Pb2+ Ions From Aqueous Solution Using Fe7s8 Nanomaterial, Jesus Cantu, Diego F. Gonzalez, Yvette Cantu, Thomas Eubanks, Jason Parsons Jul 2018

Thermodynamic And Kinetic Study Of The Removal Of Cu2+ And Pb2+ Ions From Aqueous Solution Using Fe7s8 Nanomaterial, Jesus Cantu, Diego F. Gonzalez, Yvette Cantu, Thomas Eubanks, Jason Parsons

Chemistry Faculty Publications and Presentations

In the present study, pyrrhotite (Fe7S8) was investigated for the removal of Pb2+ and Cu2+ ions from aqueous solution. The Fe7S8 material was prepared through a solvothermal method and was characterized using XRD. The average particle size for the nanomaterial was determined to be 29.86 ± 0.87 nm using XRD analysis and Scherrer's equation. Batch studies were performed to investigate the effects of pH, time, temperature, interfering ions, and the binding capacity of Pb2+ and Cu2+ ions to the Fe7S8 nanomaterial. During the pH profile studies, the optimum pH for the binding of Pb2+ and Cu2+ was determined to be …


Removal Of Chromium(Vi) And Chromium(Iii) Ions From Aqueous Solution Using Bio-Char Generated From Agricultural Waste Products, Diego Fernando Gonzalez May 2018

Removal Of Chromium(Vi) And Chromium(Iii) Ions From Aqueous Solution Using Bio-Char Generated From Agricultural Waste Products, Diego Fernando Gonzalez

Theses and Dissertations

Heavy metals are one of the most persistent and prevalent contaminants in the aquatic environment. The removal of chromium from aqueous solution, especially in the hexavalent form is difficult. New technologies, techniques and/or new materials have been designed in order to effectively and efficiently remove chromium from the aqueous environment. The project focuses on the comparison of the effects of pH, time, temperature, binding capacity on bio-char’ generated from agricultural waste produces vs an amino modified derivative of the bio-char. Pineapple skins were dried, ground, sieved, and pyrolyzed to produce a bio-char material. The bio-char was analyzed using FTIR to …


Remediation Of Lead And Copper Ions From Water Solutions Using Transition Metal Sulfides, Jesus M. Cantu Jr. Dec 2017

Remediation Of Lead And Copper Ions From Water Solutions Using Transition Metal Sulfides, Jesus M. Cantu Jr.

Theses and Dissertations

Heavy metal contamination in water solutions has been a major concern since many transition metals don’t play a role in any biological function and are actually detrimental to human health. There have been several techniques that have been implemented for the remediation of heavy metal contaminants. For this project, three metal sulfides—Fe7S8, ZnS, TiS 2—were synthesized and studied for their capabilities to remove Pb(II) and Cu(II) from water solutions. Several parameters were investigated to determine the effects of pH, time, temperature, binding capacities, and interfering ions. The room temperature adsorption capacities ranged 6.23–333.3 mg/g for Pb(II) and 1.31–250 mg/g for …


Nitrate Leaching From Sand And Pumice Geomedia Amended With Pyrogenic Carbon Materials, Jihoon Kang, Marissa Davila, Sergio Mireles, Jungseok Ho Oct 2017

Nitrate Leaching From Sand And Pumice Geomedia Amended With Pyrogenic Carbon Materials, Jihoon Kang, Marissa Davila, Sergio Mireles, Jungseok Ho

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

There is increasing interest in using pyrogenic carbon as an adsorbent for aqueous contaminants in stormwater. The objective of this study was to investigate pyrogenic carbon materials as an amendment to geomedia to reduce nitrate leaching. Batch adsorption and column experiments were conducted to evaluate the performance of a commercial activated carbon and two biochars incorporated (5% by weight) into sand and pumice columns. The batch adsorption with 50 mg L−1 of nitrate solution showed that only activated carbon resulted in a substantial adsorption for nitrate up to 41%. Tested biochars were not effective in removing aqueous nitrate and even …


N2o Emissions From California Farmlands: A Review, Elizabeth Verhoeven, Engil Isadora Pujol Pereira, Charlotte Decock, Gina Garland, Taryn Kennedy, Emma Suddick, William Horwath, Johan Six Sep 2017

N2o Emissions From California Farmlands: A Review, Elizabeth Verhoeven, Engil Isadora Pujol Pereira, Charlotte Decock, Gina Garland, Taryn Kennedy, Emma Suddick, William Horwath, Johan Six

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Of the greenhouse gases emitted from cropland, nitrous oxide (N2O) has the highest global warming potential. The state of California acknowledges that agriculture both contributes to and is affected by climate change, and in 2016 it adopted legislation to help growers reduce emissions of greenhouse gases, explicitly including N2O. Nitrous oxide emissions can vary widely due to environmental and agronomic factors with most emission estimates coming from temperate grain systems. There is, however, a dearth of emission estimates from perennial and vegetable cropping systems commonly found in California's Mediterranean climate. Therefore, emission factors (EFs) specific to California conditions are needed …


Removal Of Lead And Arsenic From Aqueous Solution By Biochar Produced From Locally-Sourced Biomass, Sergio I. Mireles Jul 2017

Removal Of Lead And Arsenic From Aqueous Solution By Biochar Produced From Locally-Sourced Biomass, Sergio I. Mireles

Theses and Dissertations

This study evaluated the effectiveness of four adsorbent materials, pyrolyzed corn stover, orange peel, pistachio shell, and magnetic biochar for their ability to adsorb lead (Pb) and arsenic (As III, As V) from aqueous solution. An increase in adsorption was seen as the pH of the solution increased from pH 2 to pH 6. Magnetic orange peel biochar with Fe3O4 particles precipitated on the surface of biochar was synthetized by co-precipitation and used for arsenic adsorption. Initial pH value had an influence on the adsorption behavior of As (III) and As (V). In the pH range of 2–6, As (V) …


Adsorptive And Kinetic Characterization Of Aqueous Zinc Removal By Biochars, Sergio Mireles, Yongsik Ok, Chu-Lin Cheng, Jihoon Kang Nov 2016

Adsorptive And Kinetic Characterization Of Aqueous Zinc Removal By Biochars, Sergio Mireles, Yongsik Ok, Chu-Lin Cheng, Jihoon Kang

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Biochars have shown a great potential to treat stormwater runoff contaminated with heavy metals due to their favorable physical and chemical characteristics. Biochar materials were produced from pyrolysis of oak tree and wood at 400C and 450C respectively, and their Zn adsorption behavior from aqueous solutions were evaluated to assess their applicability as a filter media for stormwater treatment. Two adsorption isotherm models, Freundlich and Langmuir, were used to fit the batch-scale experimental data. The kinetics of Zn adsorption was investigated under two contrasting physical condition (stagnant vs. agitated). The adsorption isotherm was better fitted with the Langmuir model (R2 …


Carbon Abatement And Emissions Associated With The Gasification Of Walnut Shells For Bioenergy And Biochar Production, Engil Isadora Pujol Pereira, Emma C. Suddick, Johan Six Mar 2016

Carbon Abatement And Emissions Associated With The Gasification Of Walnut Shells For Bioenergy And Biochar Production, Engil Isadora Pujol Pereira, Emma C. Suddick, Johan Six

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

By converting biomass residue to biochar, we could generate power cleanly and sequester carbon resulting in overall greenhouse gas emissions (GHG) savings when compared to typical fossil fuel usage and waste disposal. We estimated the carbon dioxide (CO2) abatements and emissions associated to the concurrent production of bioenergy and biochar through biomass gasification in an organic walnut farm and processing facility in California, USA. We accounted for (i) avoided-CO2 emissions from displaced grid electricity by bioenergy; (ii) CO2 emissions from farm machinery used for soil amendment of biochar; (iii) CO2 sequestered in the soil through stable biochar-C; and (iv) direct …