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Integrated Life Cycle And Techno-Economic Assessment Of The Conversion Of High Productivity, Low Lipid Algae To Renewable Fuels, Chad R. De Mill 2017 Utah State University

Integrated Life Cycle And Techno-Economic Assessment Of The Conversion Of High Productivity, Low Lipid Algae To Renewable Fuels, Chad R. De Mill

All Graduate Theses and Dissertations

The production of alternative transportation fuels is imperative to meet future energy demands without contributing to global climate change. Advances in alternative processing techniques that have emerged due to interest in microalgae as a feedstock have led to a variety of potential processing pathways for the production of bio-based fuels. A major hurdle in the algal production process is maintaining a fast and stable algae culture. Monocultures, developed for their high lipid content, suffer from low productivity, are susceptible to crashes and require a constant supply of carbon dioxide to maintain productivity. In an effort to circumvent these obstacles, algal ...


Maximum Soil Organic Carbon Storage In Midwest U.S. Cropping Systems When Crops Are Optimally Nitrogen-Fertilized, Hanna J. Poffenbarger, Daniel W. Barker, Matthew J. Helmers, Fernando E. Miguez, Daniel C. Olk, John E. Sawyer, Johan Six, Michael J. Castellano 2017 Iowa State University

Maximum Soil Organic Carbon Storage In Midwest U.S. Cropping Systems When Crops Are Optimally Nitrogen-Fertilized, Hanna J. Poffenbarger, Daniel W. Barker, Matthew J. Helmers, Fernando E. Miguez, Daniel C. Olk, John E. Sawyer, Johan Six, Michael J. Castellano

John E. Sawyer

Nitrogen fertilization is critical to optimize short-term crop yield, but its long-term effect on soil organic C (SOC) is uncertain. Here, we clarify the impact of N fertilization on SOC in typical maize-based (Zea mays L.) Midwest U.S. cropping systems by accounting for site-to-site variability in maize yield response to N fertilization. Within continuous maize and maize-soybean [Glycine max (L.) Merr.] systems at four Iowa locations, we evaluated changes in surface SOC over 14 to 16 years across a range of N fertilizer rates empirically determined to be insufficient, optimum, or excessive for maximum maize yield. Soil organic C ...


Impact Of 4r Management On Crop Production And Nitrate-Nitrogen Loss In Tile Drainage, Matthew Helmers, John Sawyer, Carl Pederson 2017 Iowa State University

Impact Of 4r Management On Crop Production And Nitrate-Nitrogen Loss In Tile Drainage, Matthew Helmers, John Sawyer, Carl Pederson

John E. Sawyer

Corn Belt corn and soybean producers are increasingly challenged to maximize crop production while addressing the contributions farm practices make to Gulf hypoxia. Based on the need for nitrate-N reductions in surface water systems to meet water quality goals, new management practices are needed to reduce nitrate-N losses at minimal cost and maximum economic benefits. This three-year field research and demonstration project is evaluating various promising N management methods and technologies by documenting the nitrate-N export and crop yield from various systems.


Agronomic Comparison Of Anhydrous Ammonia Applied With A High Speed-Low Draft Opener And Conventional Knife Injection In Corn, Krishna P. Woli, Fabián G. Fernández, John E. Sawyer, Joshua D. Stamper, David B. Mengel, Daniel W.. Barker, Mark H. Hanna 2017 Iowa State University

Agronomic Comparison Of Anhydrous Ammonia Applied With A High Speed-Low Draft Opener And Conventional Knife Injection In Corn, Krishna P. Woli, Fabián G. Fernández, John E. Sawyer, Joshua D. Stamper, David B. Mengel, Daniel W.. Barker, Mark H. Hanna

John E. Sawyer

Anhydrous ammonia (AA) is an important N fertilizer in the U.S., and with large farming operations rapid application is needed. This study evaluated the impact of AA application timing and N rates when applied with a high speed low draft (HSLD) or a conventional till knife (CTKI) on corn (Zea Mays L.) production in no-tillage fields. The study was conducted at sites located in Illinois, Iowa, and Kansas from 2007 to 2009. The experimental design was a split-plot factorial arrangement of application method, timing (fall; spring preplant, SP; and sidedress, SD), and five N rates. Fall AA application was ...


Phosphorus Indexing For Cropland: Overview And Basic Concepts Of The Iowa Phosphorus Index, A. P. Mallarino, B. M. Stewart, J. L. Baker, J. D. Downing, J. E. Sawyer 2017 Iowa State University

Phosphorus Indexing For Cropland: Overview And Basic Concepts Of The Iowa Phosphorus Index, A. P. Mallarino, B. M. Stewart, J. L. Baker, J. D. Downing, J. E. Sawyer

John E. Sawyer

Excessive phosphorus (P) loss from soils impairs surface water resources. An assessment tool or index has been proposed to identify fields with high potential risk of P delivery. The P index integrates P source and transport factors into a decision making process that may lead to changes in current P management and soil conservation practices. The index recognizes that a single soil P threshold alone is not an appropriate evaluation factor because of the varying conditions across fields. Although most indices being developed in the United States include similar factors, source and transport characteristics are considered in various ways to ...


Impacts Of Climate Change On Hydrology, Water Quality And Crop Productivity In The Ohio-Tennessee River Basin, Yiannis Panagopoulos, Philip W. Gassman, Raymond W. Arritt, Daryl E. Herzmann, Todd D. Campbell, Adriana Valcu, Manoj K. Jha, Catherine L. Kling, Raghavan Srinivasan, Michael White, Jeffrey G. Arnold 2017 Iowa State University

Impacts Of Climate Change On Hydrology, Water Quality And Crop Productivity In The Ohio-Tennessee River Basin, Yiannis Panagopoulos, Philip W. Gassman, Raymond W. Arritt, Daryl E. Herzmann, Todd D. Campbell, Adriana Valcu, Manoj K. Jha, Catherine L. Kling, Raghavan Srinivasan, Michael White, Jeffrey G. Arnold

Catherine Kling

Nonpoint source pollution from agriculture is the main source of nitrogen and phosphorus in the stream systems of the Corn Belt region in the Midwestern US. The eastern part of this region is comprised of the Ohio-Tennessee River Basin (OTRB), which is considered a key contributing area for water pollution and the Northern Gulf of Mexico hypoxic zone. A point of crucial importance in this basin is therefore how intensive corn-based cropping systems for food and fuel production can be sustainable and coexist with a healthy water environment, not only under existing climate but also under climate change conditions in ...


Maximum Soil Organic Carbon Storage In Midwest U.S. Cropping Systems When Crops Are Optimally Nitrogen-Fertilized, Hanna J. Poffenbarger, Daniel W. Barker, Matthew J. Helmers, Fernando E. Miguez, Daniel C. Olk, John E. Sawyer, Johan Six, Michael J. Castellano 2017 Iowa State University

Maximum Soil Organic Carbon Storage In Midwest U.S. Cropping Systems When Crops Are Optimally Nitrogen-Fertilized, Hanna J. Poffenbarger, Daniel W. Barker, Matthew J. Helmers, Fernando E. Miguez, Daniel C. Olk, John E. Sawyer, Johan Six, Michael J. Castellano

Agronomy Publications

Nitrogen fertilization is critical to optimize short-term crop yield, but its long-term effect on soil organic C (SOC) is uncertain. Here, we clarify the impact of N fertilization on SOC in typical maize-based (Zea mays L.) Midwest U.S. cropping systems by accounting for site-to-site variability in maize yield response to N fertilization. Within continuous maize and maize-soybean [Glycine max (L.) Merr.] systems at four Iowa locations, we evaluated changes in surface SOC over 14 to 16 years across a range of N fertilizer rates empirically determined to be insufficient, optimum, or excessive for maximum maize yield. Soil organic C ...


Review Of: Eat Your Genes: How Genetically Modified Food Is Entering Our Diet (Stephen Nottingham Ed.), Natalie Duval 2017 University of New Hampshire

Review Of: Eat Your Genes: How Genetically Modified Food Is Entering Our Diet (Stephen Nottingham Ed.), Natalie Duval

RISK: Health, Safety & Environment

Review of the book: "Eat Your Genes: How Genetically Modified Food Is Entering Our Diet," by Stephen Nottingham, (St. Martin's Press 1999). Introduction, Glossary, Bibliography, Index. ISBN 1-85649-578-7 [212 pp. $17.95. Softbound, St. Martin's Press, Inc., New York, NY 10010].


Relating Watershed Characteristics To Elevated Stream Escherichia Coli Levels In Agriculturally Dominated Landscapes: An Iowa Case Study, Conrad Brendel, Michelle L. Soupir 2017 Iowa State University

Relating Watershed Characteristics To Elevated Stream Escherichia Coli Levels In Agriculturally Dominated Landscapes: An Iowa Case Study, Conrad Brendel, Michelle L. Soupir

Agricultural and Biosystems Engineering Publications

Fecal Indicator Bacteria (FIB) such as Escherichia coli (E. coli) are a leading cause of surface water impairments in the United States. However, the relative impacts of different watershed characteristics on microbial water quality in agriculturally dominated watersheds are unclear. Spatial and statistical analyses were utilized to examine relationships between watershed characteristics and FIB and a multiple regression model was created. Geometric mean E. coli concentration data were obtained for 395 ambient water quality monitoring locations in Iowa. Watersheds were delineated for thirty randomly selected monitoring locations and drainage areas ranged from 93 to 1.1 million hectares. Watershed characteristics ...


Virtual Operator Modeling Approach For Construction Machinery, Yu Du, Michael C. Dorneich, Brian L. Steward, Eric R. Anderson, Lawrence F. Kane, Brian J. Gilmore 2017 Iowa State University

Virtual Operator Modeling Approach For Construction Machinery, Yu Du, Michael C. Dorneich, Brian L. Steward, Eric R. Anderson, Lawrence F. Kane, Brian J. Gilmore

Michael C. Dorneich

Greater understanding of how highly skilled operators achieve high machine performance and productivity can inform the development of automation technology for construction machinery. Current human operator models, however, have limited fidelity and may not be useful for machinery automation. In addition, while physical modeling and simulation is widely employed in product development, current operator simulation models may be a limiting factor in assessing the performance envelope of virtual prototypes. A virtual operator modelling approach for construction machinery was developed. Challenges to the development of human operator models include determining what cues and triggers human operators use, how human operators make ...


Anhydrous Ammonia Pretreatment Of Corn Stover And Enzymatic Hydrolysis Of Glucan From Pretreated Corn Stover, Minliang Yang, Weitao Zhang, Kurt A. Rosentrater 2017 Iowa State University

Anhydrous Ammonia Pretreatment Of Corn Stover And Enzymatic Hydrolysis Of Glucan From Pretreated Corn Stover, Minliang Yang, Weitao Zhang, Kurt A. Rosentrater

Agricultural and Biosystems Engineering Publications

As a promising alternative of fossil fuel, ethanol has been widely used. In recent years, much attention has been devoted to bioethanol production from lignocellulosic biomass. In previous research, it is found that the pretreatment method named low-moisture anhydrous ammonia (LMAA) has the advantage of high conversion efficiency and less washing requirements. The purpose of this study was to explore the optimal conditions by employing the LMAA pretreatment method. Corn stover was treated under three levels of moisture content: 20, 50, 80 w.b.% (wet basis), and three levels of particle size: <0.09, 0.09–2, >2 mm; it was also ammoniated with a ...


Detection Of Extremely Low Concentration Waterborne Pathogen Using A Multiplexing Self-Referencing Sers Microfluidic Biosensor, Chao Wang, Foram Madiyar, Chenxu Yu, Jun Li 2017 Iowa State University

Detection Of Extremely Low Concentration Waterborne Pathogen Using A Multiplexing Self-Referencing Sers Microfluidic Biosensor, Chao Wang, Foram Madiyar, Chenxu Yu, Jun Li

Agricultural and Biosystems Engineering Publications

Background It is challenging to achieve ultrasensitive and selective detection of waterborne pathogens at extremely low levels (i.e., single cell/mL) using conventional methods. Even with molecular methods such as ELISA or PCR, multi-enrichment steps are needed which are labor and cost intensive. In this study, we incorporated nano-dielectrophoretic microfluidic device with Surface enhanced Raman scattering (SERS) technique to build a novel portable biosensor for easy detection and characterization of Escherichia coli O157:H7 at high sensitivity level (single cell/mL).

Results A multiplexing dual recognition SERS scheme was developed to achieve one-step target detection without the need to ...


Pilot-Scale Testing Of Renewable Biocatalyst For Swine Manure Treatment And Mitigation Of Odorous Vocs, Ammonia And Hydrogen Sulfide Emissions, Devin L. Maurer, Jacek A. Koziel, Kelsey M. Bruning, David B. Parker 2017 Iowa State University

Pilot-Scale Testing Of Renewable Biocatalyst For Swine Manure Treatment And Mitigation Of Odorous Vocs, Ammonia And Hydrogen Sulfide Emissions, Devin L. Maurer, Jacek A. Koziel, Kelsey M. Bruning, David B. Parker

Agricultural and Biosystems Engineering Publications

Comprehensive control of odors, hydrogen sulfide (H2S), ammonia (NH3), and greenhouse gas (GHG) emissions associated with swine production is a critical need. A pilot-scale experiment was conducted to evaluate surface-applied soybean peroxidase (SBP) and calcium peroxide (CaO2) as a manure additive to mitigate emissions of odorous volatile organic compounds (VOC) including dimethyl disulfide/methanethiol (DMDS/MT), dimethyl trisulfide, n-butyric acid, valeric acid, isovaleric acid, p-cresol, indole, and skatole. The secondary impact on emissions of NH3, H2S, and GHG was also measured. The SBP was tested at four treatments (2.28–45 ...


The Green Experiment: Cities, Green Stormwater Infrastructure, And Sustainability, Christopher M. Chini, James F. Canning, Kelsey L. Schreiber, Joshua M. Peschel, Ashlynn S. Stillwell 2017 University of Illinois at Urbana-Champaign

The Green Experiment: Cities, Green Stormwater Infrastructure, And Sustainability, Christopher M. Chini, James F. Canning, Kelsey L. Schreiber, Joshua M. Peschel, Ashlynn S. Stillwell

Agricultural and Biosystems Engineering Publications

Green infrastructure is a unique combination of economic, social, and environmental goals and benefits that requires an adaptable framework for planning, implementing, and evaluating. In this study, we propose an experimental framework for policy, implementation, and subsequent evaluation of green stormwater infrastructure within the context of sociotechnical systems and urban experimentation. Sociotechnical systems describe the interaction of complex systems with quantitative and qualitative impacts. Urban experimentation—traditionally referencing climate change programs and their impacts—is a process of evaluating city programs as if in a laboratory setting with hypotheses and evaluated results. We combine these two concepts into a singular ...


The Irreversible Momentum Of Clean Energy, Barack Obama 2017 President of the United States

The Irreversible Momentum Of Clean Energy, Barack Obama

US Department of Energy Publications

The release of carbon dioxide (CO2) and other greenhouse gases (GHGs) due to human activity is increasing global av-erage surface air temperatures, disrupting weather patterns, and acidifying the ocean (1). Left unchecked, the continued growth of GHG emissions could cause global average tem-peratures to increase by another 4°C or more by 2100 and by 1.5 to 2 times as much in many midcontinent and far northern locations (1). Although our understanding of the impacts of climate change is increasingly and disturbingly clear, there is still debate about the proper course for U.S. policy—a debate that is ...


Influence Of Uv Treatment On The Food Safety Status Of A Model Aquaponic System, Sai Deepikaa Elumalai, Angela M. Shaw, D. Allen Pattillo, Christopher J. Currey, Kurt A. Rosentrater, Kun Xie 2017 Iowa State University

Influence Of Uv Treatment On The Food Safety Status Of A Model Aquaponic System, Sai Deepikaa Elumalai, Angela M. Shaw, D. Allen Pattillo, Christopher J. Currey, Kurt A. Rosentrater, Kun Xie

Agricultural and Biosystems Engineering Publications

Few microbial studies in aquaponics, a growing trend in food production, have been conducted to determine food safety status. The aim of this study was to determine the food safety status and the effectiveness of ultraviolet treatment (15 W, luminous flux of 900 lm) as a food safety intervention in reducing the microbial loads of the water system in a model aquaponic unit growing lettuce, basil, and barramundi (Australian Sea Bass). Sweet basil, bibb lettuce, water samples, and fish swabs were collected throughout the 118-day production period, and microbial analysis was conducted in triplicate for the presence of E. coli ...


Predicting Field Water Balance, Crop Yield, And The Economics Of Drainage Under Various Cropping Systems Using Drainmod, Shailendra Singh 2017 South Dakota State University

Predicting Field Water Balance, Crop Yield, And The Economics Of Drainage Under Various Cropping Systems Using Drainmod, Shailendra Singh

Shailendra Singh

Subsurface drainage received considerable attention during the recent few years in South Dakota. While subsurface drainage is a widely accepted water management practice for increasing crop yield, research implicated tile drainage in surface and groundwater quality problems. Conservation practices such as crop rotation and controlled drainage may decrease tile flows and improve water quality. A two-year (2014-2015) subsurface drainage study was conducted at South Dakota State University Southeast Research Farm (SERF) near Beresford, South Dakota to evaluate the effectiveness of selected conservation practices in reducing drainage volume and nitrate losses. Six experimental plots, under corn-soybean rotation, divided into drained and ...


Understanding The Impacts Of Ammonia Fiber Expansion (Afex™) Pretreatment And Densification On Densified Products Quality And The Bioproducts Yield Through Enzymatic Hydrolysis And Fast Pyrolysis, Vijay Sundaram 2017 South Dakota State University

Understanding The Impacts Of Ammonia Fiber Expansion (Afex™) Pretreatment And Densification On Densified Products Quality And The Bioproducts Yield Through Enzymatic Hydrolysis And Fast Pyrolysis, Vijay Sundaram

Theses and Dissertations

Lignocellulosic biomass poses significant challenges during handling, transportation, and storage due to its low bulk density. Densification involves conversion of the low bulk density biomass into a highly compacted product which helps in improving the handling, transporting, and storage obstacles associated with biomass logistics. Besides the logistical challenges, the recalcitrant nature of the lignocellulosic biomass makes it even more challenging during the enzymatic hydrolysis. The carbohydrate components, cellulose and hemicellulose are not readily accessible by the enzymes during the hydrolysis process due to the presence of lignin. Pretreatment is the process to convert the native recalcitrant biomass in the form ...


A Meta-Analysis Of The Effect Of Industry Engagement On Student Learning In Undergraduate Programs, Caleb Burns, Shweta Chopra 2017 Iowa State University

A Meta-Analysis Of The Effect Of Industry Engagement On Student Learning In Undergraduate Programs, Caleb Burns, Shweta Chopra

Agricultural and Biosystems Engineering Publications

Universities incorporate industry engagement alongside classroom teaching to prepare today’s students to become tomorrow’s entrepreneurs, workers, or researchers to make the world a better place. Successful industry engagement activities provide students with life-changing experiences that can: (a) enhance students’ networking connections with professionals who can potentially provide employment references and future job positions, (b) give students an opportunity to gain practical experience by observing and applying the methods and theories learned in classroom to real-world scenarios, (c) allow students to gain experience in their prospective career path, and (d) improve students’ professional communication skills. Existing research has suggested ...


Pilot-Scale Denitrification Bioreactors For Replicated Field Research, Natasha L. Hoover, Michelle L. Soupir, Richard D. VanDePol, Timothy R. Goode, Ji Yeow Law 2017 Iowa State University

Pilot-Scale Denitrification Bioreactors For Replicated Field Research, Natasha L. Hoover, Michelle L. Soupir, Richard D. Vandepol, Timothy R. Goode, Ji Yeow Law

Agricultural and Biosystems Engineering Publications

Carbon-based denitrification bioreactors are designed to intercept tile drainage and are a promising technology for reducing NO3- export to surface water. While these systems have been tested extensively in the laboratory, the ability to study in-field bioreactors under controlled conditions with statistical replicates has been limited. Nine pilot-scale bioreactors (5.79 x 1.05 x 1.07 m) were designed and installed for systematic field testing, allowing for variation in retention time, fill material, and influent water quality parameters. Each bioreactor is constructed from a concrete trench in-line with influent flow control, dosing port, flow diffusion, and effluent water ...


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