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Full-Text Articles in Physical Sciences and Mathematics

Advancing Computational Toxicology In A Regulatory Setting: A Selected Review Of The Accomplishments Of Gilman D. Veith (1944–2013), Steven P. Bradbury, Christine L. Russom, Patricia K. Schmieder, Terry W. Schultz, Robert Diderich, Charles M. Auer Jan 2015

Advancing Computational Toxicology In A Regulatory Setting: A Selected Review Of The Accomplishments Of Gilman D. Veith (1944–2013), Steven P. Bradbury, Christine L. Russom, Patricia K. Schmieder, Terry W. Schultz, Robert Diderich, Charles M. Auer

Steven P. Bradbury

With the passing of Dr. Gilman D. Veith on August 18, 2013, the research community lost one of its true visionaries in the development and implementation of alternative in silico and in vitro toxicology models in human health and ecological risk assessment. His career spanned more than four decades, during which he repeatedly demonstrated vision and leadership to advance alternative testing and assessment research and to guide the adoption of research accomplishments into U.S. and international chemical regulatory programs. His ability to advance toxicological and environmental exposure research, and associated quantitative structure– activity relationships (QSARs), for application in environmental regulatory …

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The North American Carbon Program Multi-Scale Synthesis And Terrestrial Model Intercomparison Project – Part 2: Environmental Driver Data, Y. Wei, S. Liu, D. N. Huntzinger, A. M. Michalak, N. Viovy, W. M. Post, C. R. Schwalm, K. Schaefer, A. R. Jacobson, Chaoqun (Crystal) Lu, Hanqin Tian, D. M. Ricciuto, R. B. Cook, J. Mao, X. Shi Dec 2014

The North American Carbon Program Multi-Scale Synthesis And Terrestrial Model Intercomparison Project – Part 2: Environmental Driver Data, Y. Wei, S. Liu, D. N. Huntzinger, A. M. Michalak, N. Viovy, W. M. Post, C. R. Schwalm, K. Schaefer, A. R. Jacobson, Chaoqun (Crystal) Lu, Hanqin Tian, D. M. Ricciuto, R. B. Cook, J. Mao, X. Shi

Chaoqun (Crystal) Lu

Ecosystems are important and dynamic components of the global carbon cycle, and terrestrial biospheric models (TBMs) are crucial tools in further understanding of how terrestrial carbon is stored and exchanged with the atmosphere across a variety of spatial and temporal scales. Improving TBM skills, and quantifying and reducing their estimation uncertainties, pose significant challenges. The Multi-scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP) is a formal multi-scale and multi-model intercomparison effort set up to tackle these challenges. The MsTMIP protocol prescribes standardized environmental driver data that are shared among model teams to facilitate model–model and model–observation comparisons. This paper describes …

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Evaluation Of Trophic Niche Overlap Between Native Fishes And Young-Of-The-Year Common Carp, Michael J. Weber, Jessica M. Howell, Michael L. Rown Jul 2014

Evaluation Of Trophic Niche Overlap Between Native Fishes And Young-Of-The-Year Common Carp, Michael J. Weber, Jessica M. Howell, Michael L. Rown

Michael J Weber Dr

Common carp Cyprinus carpio is a ubiquitous invasive species that commonly imposes negative effects on aquatic ecosystems. However, research evaluating the effects of carp on native fishes is limited. Carp are highly fecund and larvae and juveniles can be abundant. If age-0 carp use similar prey resources as native fishes, they may compete if food becomes limited. We used traditional diet analysis for samples during Jul. and Aug. 2008 in Brant Lake. Stable sotopes were used for samples collected during Aug. and Sep. 2009 in Brant Lake and Lake Sinai to examine prey resource use by age-0 carp and four …

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Continuous, Pulsed And Disrupted Nutrient Subsidy Effects On Ecosystem Productivity, Stability, And Energy Flow, Michael J. Weber, Michael L. Brown Feb 2013

Continuous, Pulsed And Disrupted Nutrient Subsidy Effects On Ecosystem Productivity, Stability, And Energy Flow, Michael J. Weber, Michael L. Brown

Michael J Weber Dr

Resource pulses and subsidies can supply ecosystems with an important source of nutrients that supports additional productivity at multiple trophic levels. Common carp Cyprinus carpio provide ecosystems with a continuous nutrient subsidy through bioturbation and excretion but may also initiate a nutrient pulse through carcass decomposition. We examined how continuous (common carp foraging and excretion), pulsed (carcass decomposition) and disrupted (carp introduced and then removed) nutrient subsidies differed in their ability to alter nutrient availability, ecosystem productivity and stability and energy flow. Nitrogen and phosphorus availability and primary production were highest in pulsed, intermediate in continuous and lowest for disrupted …

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Predicting Modes Of Toxic Action From Chemical Structure, Steven P. Bradbury, Christine L. Russom, Steven J. Broderius, Dean J. Hammermeister, Robert A. Drummond, Gilman D. Veith Jan 2013

Predicting Modes Of Toxic Action From Chemical Structure, Steven P. Bradbury, Christine L. Russom, Steven J. Broderius, Dean J. Hammermeister, Robert A. Drummond, Gilman D. Veith

Steven P. Bradbury

Like many of the papers in the Environmental Toxicology and Chemistry “Top 100” list, the development of the fathead minnow database [1] and the assignment of modes of action to the 617 chemicals therein resulted from a comprehensive research effort by a multidisciplinary team of researchers with expertise in quantitative structure–activity relationship (QSAR) modeling, chemistry, toxicokinetics, joint toxicity of chemical mixtures, and behavioral and aquatic toxicology. The fathead minnow database was the culmination of the US Environmental Protection Agency’s (USEPA) QSAR research program, which spanned nearly 20 yr, a rare program because many research planning efforts typically run within a …

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Food Benefit And Climate Warming Potential Of Nitrogen Fertilizer Uses In China, Hanqin Tian, Chaoqun (Crystal) Lu, Jerry Melillo, Wei Ren, Yao Huang, Xiaofeng Xu, Mingliang Liu, Chi Zhang, Guangsheng Chen, Shufen Pan, Jiyuan Liu, John Reilly Jan 2012

Food Benefit And Climate Warming Potential Of Nitrogen Fertilizer Uses In China, Hanqin Tian, Chaoqun (Crystal) Lu, Jerry Melillo, Wei Ren, Yao Huang, Xiaofeng Xu, Mingliang Liu, Chi Zhang, Guangsheng Chen, Shufen Pan, Jiyuan Liu, John Reilly

Chaoqun (Crystal) Lu

Chemical nitrogen (N) fertilizer has long been used to help meet the increasing food demands in China, the top N fertilizer consumer in the world. Growing concerns have been raised on the impacts of N fertilizer uses on food security and climate change, which is lack of quantification. Here we use a carbon–nitrogen (C–N) coupled ecosystem model, to quantify the food benefit and climate consequence of agronomic N addition in China over the six decades from 1949 to 2008. Results show that N fertilizer-induced crop yield and soil C sequestration had reached their peaks, while nitrous oxide (N2O) emission continued …

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Overview Of Fuel Ethanol Production And Distillers Grains, Kurt A. Rosentrater Jan 2012

Overview Of Fuel Ethanol Production And Distillers Grains, Kurt A. Rosentrater

Kurt A. Rosentrater

Modern societies face many challenges, including growing populations, increased demands for food, clothing, housing, consumer goods, and the concomitant raw materials required to produce all of these. Additionally, there is a growing need for energy, which is most easily met by use of fossil fuels (e.g., coal, natural gas, and petroleum). In 2008, the overall U.S. demand for energy was 99.3 x 1015 Btu (1.05 x 1014 MJ); 84% of this was supplied by fossil sources (U.S. EIA, 2009). Transportation fuels accounted for 28% of all energy consumed during this time, and nearly 97% of this came from fossil sources. …

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Manufacturing Of Fuel Ethanol And Distillers Grains—Current And Evolving Processes, Kurt A. Rosentrater, Klein Ileleji, David B. Johnson Jan 2012

Manufacturing Of Fuel Ethanol And Distillers Grains—Current And Evolving Processes, Kurt A. Rosentrater, Klein Ileleji, David B. Johnson

Kurt A. Rosentrater

Before examining all of the different possible uses of distillers dried grains with solubles (DDGS), a discussion regarding ethanol and DDGS production methods is warranted. This chapter will cover current production processes and some of the new practices that have been developed and are being adopted at plants, including front-end fractionation and back-end fractionation. Additionally, standard coproduct definitions will be discussed, as they govern the marketing and sales of these materials.

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Toward A Scientific Understanding Of Ddgs, Keshun Liu, Kurt A. Rosentrater Jan 2012

Toward A Scientific Understanding Of Ddgs, Keshun Liu, Kurt A. Rosentrater

Kurt A. Rosentrater

Recently, many people have asked what the fuel ethanol industry is going to do about the growing piles of nonfermented leftovers. Actually this question has been around for quite some time. As early as the 1940s, one report stated that "Grain distillers have developed equipment and an attractive market for their recovered grains" (Boruff, 1947), while another report described that "Distillers are recovering, drying, and marketing their destarched grain stillage as distillers dried grains and dried solubles" (Boruff, 1952). So it appears that a viable solution had already been developed as far back as the 1940s. And by the early …

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Overview Of Corn-Based Fuel Ethanol Coproducts: Production And Use, Kurt A. Rosentrater Aug 2011

Overview Of Corn-Based Fuel Ethanol Coproducts: Production And Use, Kurt A. Rosentrater

Kurt A. Rosentrater

Modern societies face many challenges, including growing populations, increased demands for food, clothing, housing, consumer goods, and the raw materials required to produce all of these. Additionally, there is a growing need for energy, which is most easily met by use of fossil fuels (e.g., coal, natural gas, petroleum). For example, in 2008, the overall U.S. demand for energy was 99.3 x 1015 Btu (1.05 x 1014 MJ); 84% of this was supplied by fossil sources. Transportation fuels accounted for 28% of all energy consumed during this time, and nearly 97% of this came from fossil sources. Domestic production of …

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Developing Criteria For Evaluating The Sustainability Of Emerging Energy, Kurt A. Rosentrater, Elif Kongar Apr 2011

Developing Criteria For Evaluating The Sustainability Of Emerging Energy, Kurt A. Rosentrater, Elif Kongar

Kurt A. Rosentrater

Over the last decade, the interest in and production of biofuels has grown rapidly. Renewable transportation fuels can be produced from a variety of substrates, using various processing strategies. Feedstock preference and factory scale are geographic dependent. However, it is important to understand the implications of deploying these types of systems on a large scale, both throughout the U.S. as well as globally. To assess the sustainability of various biofuel options, it is crucial to evaluate their performance according to a number of attributes. This has been done using Life Cycle Assessment (LCA). Even so, comparisons among biofuel options are …

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Genetic Analysis Of The Federally Endangered Winged Mapleleaf Mussel To Aid Proposed Re-Introduction Efforts, Kevin J. Roe Sep 2010

Genetic Analysis Of The Federally Endangered Winged Mapleleaf Mussel To Aid Proposed Re-Introduction Efforts, Kevin J. Roe

Kevin J. Roe

The winged mapleleaf, Quadrula fragosa, historically occurred in the Mississippi, Tennessee, Ohio, and Cumberland river drainages, but has suffered severe population and range reductions. At the time that the species was federally listed as endangered, its range was thought to have been reduced to a stretch of the St. Croix River between northwestern Wisconsin and east-central Minnesota. Recently, morphologically “Q. fragosa-like” specimens were discovered at sites in Arkansas (Ouachita River and Saline River), Missouri (Bourbeuse River), and Oklahoma (Little River). Subsequently, a plan was proposed to re-introduce Q. fragosa into portions of its historic range where its been extirpated from …

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Physical And Chemical Characterization Of Fuel Ethanol Coproducts Relevant To Value-Added Uses, Rumela Bhadra, Kurt A. Rosentrater, Kasiviswanathan Muthukumarappan Sep 2010

Physical And Chemical Characterization Of Fuel Ethanol Coproducts Relevant To Value-Added Uses, Rumela Bhadra, Kurt A. Rosentrater, Kasiviswanathan Muthukumarappan

Kurt A. Rosentrater

One of the fastest growing industries in the United States is the fuel ethanol industry. In terms of ethanol production capability, the industry has grown by more than 600% since the year 2000. The major coproducts from corn-based ethanol include distillers dried grains with solubles (DDGS) and carbon dioxide. DDGS is used as a livestock feed because it contains high quantities of protein, fiber, amino acids, and other nutrients. The goal of this study was to quantify various chemical and physical properties of DDGS, distillers wet grains (DWG), and distillers dried grain (DDG) from several plants in South Dakota. Chemical …

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Proteomic Analysis Of Ethene-Enriched Groundwater Microcosms From A Vinyl Chloride-Contaminated Site, Adina S. Chuang, Yang Oh Jin, Laura S. Schmidt, Yalan Li, Samuel Fogel, Donna Smoler, Timothy E. Mattes Mar 2010

Proteomic Analysis Of Ethene-Enriched Groundwater Microcosms From A Vinyl Chloride-Contaminated Site, Adina S. Chuang, Yang Oh Jin, Laura S. Schmidt, Yalan Li, Samuel Fogel, Donna Smoler, Timothy E. Mattes

Adina Howe

Contamination of groundwater with vinyl chloride (VC), a known human carcinogen, is a common environmental problem at plastics manufacturing, dry cleaning, and military sites. At many sites, there is the potential to cleanup VC groundwater plumes with aerobic VC-oxidizing microorganisms (e.g., methanotrophs, etheneotrophs, and VC-assimilating bacteria). Environmental biotechnologies that reveal the presence and activity of VC-oxidizing bacteria in contaminated groundwater samples would provide valuable lines of evidence that bioremediation of VC is occurring at a site. We applied targeted shotgun mass spectrometry-based proteomic methods to ethene-enriched groundwater microcosms from a VC-contaminated site. Polypeptides from the enzymes alkene monooxygenase (EtnC) and …

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Application Of The Tissue Residue Approach In Ecological Risk Assessment, Steven P. Bradbury, Keith G. Sappington, Todd S. Bridges, Russell J. Erickson, A. Jan Hendriks, Roman P. Lanno, James P. Meador, David R. Mount, Mike H. Salazar, Doug J. Spry Jan 2010

Application Of The Tissue Residue Approach In Ecological Risk Assessment, Steven P. Bradbury, Keith G. Sappington, Todd S. Bridges, Russell J. Erickson, A. Jan Hendriks, Roman P. Lanno, James P. Meador, David R. Mount, Mike H. Salazar, Doug J. Spry

Steven P. Bradbury

The objective of this work is to present a critical review of the application of the tissue residue approach (TRA) in ecological risk and/or impact assessment (ERA) of chemical stressors and environmental criteria development. A secondary goal is to develop a framework for integrating the TRA into ecological assessments along with traditional, exposure concentration-based assessment approaches. Although widely recognized for its toxicological appeal, the utility of the TRA in specific applications will depend on numerous factors, such as chemical properties, exposure characteristics, assessment type, availability of tissue residue-response data, and ability to quantify chemical exposure. Therefore, the decision to use …

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Meeting The Common Needs Of A More Effective And Efficient Testing And Assessment Paradigm For Chemical Risk Management, Steven P. Bradbury, Vicki Dellarco, Tala Henry, Phil Sayre, Jennifer Seed Jan 2010

Meeting The Common Needs Of A More Effective And Efficient Testing And Assessment Paradigm For Chemical Risk Management, Steven P. Bradbury, Vicki Dellarco, Tala Henry, Phil Sayre, Jennifer Seed

Steven P. Bradbury

Significant advances have been made in human health and ecological risk assessment over the last decade. Substantial challenges, however, remain in providing credible scientific information in a timely and efficient manner to support chemical risk assessment and management decisions. A major challenge confronting risk managers is the need for critical information to address risk uncertainties in large chemical inventories such as high- and medium-production-volume industrial chemicals or pesticide inert ingredients. From a strategic and tactical viewpoint, an integrated approach that relies on all existing knowledge and uses a range of methods, including those from emerging and novel technologies, is needed …

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Greening The Curriculum: Augmenting Engineering And Technology Courses With Sustainability Topics, Kurt A. Rosentrater, Elif Kongar Jan 2010

Greening The Curriculum: Augmenting Engineering And Technology Courses With Sustainability Topics, Kurt A. Rosentrater, Elif Kongar

Kurt A. Rosentrater

Duties of engineers and technologists often entail designing and implementing solutions to problems. It is their responsibility to be cognizant of the impacts of their designs on and thus, their accountability to society in general. They must also be aware of subsequent effects upon the environment. They need to be able to concurrently satisfy these often competing priorities as well as constraints specific to the technical challenges at hand. Responding to these contending forces are the growing fields of green engineering and sustainable engineering. Both of these areas encompass many concepts, ideas and tools all of which are essential for …

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Costs Of Pelleting To Enhance The Logistics Of Distillers Grains Shipping, Kurt A. Rosentrater, Elif Kongar Oct 2009

Costs Of Pelleting To Enhance The Logistics Of Distillers Grains Shipping, Kurt A. Rosentrater, Elif Kongar

Kurt A. Rosentrater

Biofuels, especially corn-based ethanol, can help meet some of the increasing demand for transportation fuels. Currently, the most heavily utilized substrate is corn grain, which is readily converted into ethanol at a relatively low cost compared to other biomass sources. The production of ethanol in the U.S. has been dramatically increasing during the last several years; so too has the quantity of manufacturing coproducts. These nonfermentable residues are most often dried and sold as distillers dried grains with solubles – DDGS. Even though these materials are used to feed livestock in local markets, as the size of the industry continues …

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Survey Of Us Fuel Ethanol Plants, Jessica A. Saunders, Kurt A. Rosentrater Jul 2009

Survey Of Us Fuel Ethanol Plants, Jessica A. Saunders, Kurt A. Rosentrater

Kurt A. Rosentrater

The ethanol industry is growing in response to increased consumer demands for fuel as well as the renewable fuel standard. Corn ethanol processing creates the following products: 1/3 ethanol, 1/3 distillers grains, and 1/3 carbon dioxide. As the production of ethanol increases so does the generation of its coproducts, and viable uses continually need to be developed. A survey was mailed to operational US ethanol plants to determine current practices. It inquired about processes, equipment used, end products, and desired future directions for coproducts. Results indicated that approximately one-third of plant managers surveyed expressed a willingness to alter current drying …

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A Data Envelopment Analysis Model For Renewable Energy Technology Selection, Elif Kongar, Kurt A. Rosentrater Apr 2009

A Data Envelopment Analysis Model For Renewable Energy Technology Selection, Elif Kongar, Kurt A. Rosentrater

Kurt A. Rosentrater

Public and media interest in alternative energy sources, such as renewable fuels, has rapidly increased in recent years due to higher prices for oil and natural gas. However, the current body of research providing comparative decision making models that either rank these alternative energy sources and/or determine the best possible alternatives is still limited. This paper aims at filling this gap by proposing a Data Envelopment Analysis (DEA) model structure for ranking energy source alternatives under varying circumstances. The model considers both the economics of energy sources and additional environmental criteria such as CO2 emissions and damage cost. Numerical examples …

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Quantifying Total And Sustainable Agricultural Biomass Resources In South Dakota—A Preliminary Assessment, Kurt A. Rosentrater, Dennis Todey, Russell Persyn Jan 2009

Quantifying Total And Sustainable Agricultural Biomass Resources In South Dakota—A Preliminary Assessment, Kurt A. Rosentrater, Dennis Todey, Russell Persyn

Kurt A. Rosentrater

Conversion of biomass is considered the next major advance in biorenewable fuels, energy, and products. Wholesale conversion to biomass utilization could result in removal of current crop residues from agricultural fields (on prime agricultural lands) or even implementation of different crops and cropping strategies (i.e., switchgrass on marginal lands). To date, the driver for biomass processing has been economics and limitations on the conversion of the lignocellulose. Over the last forty years significant investments and resultant changes in management practices in the agricultural sector have focused on soil and water conservation. One of the major efforts has focused on conservation-till …

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Properties Of Solvent Extracted Low-Oil Corn Distillers Dried Grains With Solubles, Kurt A. Rosentrater, Jennifer A. Saunders Jan 2009

Properties Of Solvent Extracted Low-Oil Corn Distillers Dried Grains With Solubles, Kurt A. Rosentrater, Jennifer A. Saunders

Kurt A. Rosentrater

Corn-based ethanol is exponentially growing in the US, as is the need for valuable uses for coproducts of the production process, such as distillers dried grains with solubles (DDGS). Currently, DDGS is used as livestock feed, thereby replacing some corn components in animal diets. As the industry continues to grow, there will be an increased need to find additional uses for DDGS. Physical and chemical properties of coproduct streams are becoming increasingly investigated, as these characteristics affect many aspects of utilization, such as target species, optimal dietary substitution rates, transportation, flowability, and behavior during storage. Potential avenues for future use …

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Design Properties For Molded, Corn-Based Ddgs-Filled Phenolic Resin, R. A. Tatara, Kurt A. Rosentrater, S. Suraparaju Jan 2009

Design Properties For Molded, Corn-Based Ddgs-Filled Phenolic Resin, R. A. Tatara, Kurt A. Rosentrater, S. Suraparaju

Kurt A. Rosentrater

With the rapid growth in the ethanol fuel industry in recent years, considerable research is being devoted to maximizing the use of processing coproducts, such as distillers dried grains with solubles (DDGS), typically for livestock diets. Because these residues contain high fiber levels, they may be amendable to incorporation into polymers as well, which is an option that could garner greater economic returns. Thus, the goal of this study was to demonstrate the viability of using corn-based DDGS as a biofiller with phenolic resin, in order to produce a novel biomaterial. DDGS was blended with phenolic resin at four levels …

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Improved Uses And Values For The Byproducts Of The Developing Biofuels Industry, Kurt A. Rosentrater Aug 2008

Improved Uses And Values For The Byproducts Of The Developing Biofuels Industry, Kurt A. Rosentrater

Kurt A. Rosentrater

No abstract provided.

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Modeling The Effects Of Value-Added Processing And Logistics Using Arena, Kurt A. Rosentrater, Elif Kongar Mar 2008

Modeling The Effects Of Value-Added Processing And Logistics Using Arena, Kurt A. Rosentrater, Elif Kongar

Kurt A. Rosentrater

Scarcity and cost of nonrenewable fossil fuels have been a growing focus of many energy-dependent nations, including the U.S., for the past couple of decades. There are mainly two ways to approach these problems: (1) reducing the energy dependency and/or (2) developing alternative means of energy production. Utilizing biofuels, which are renewable sources of energy, is a promising way to produce energy. But, as this industry grows, so too does the quantity of byproducts, which are known as DDGS. This paper discusses a model that has been developed to analyze the economic viability of DDGS processing, and includes both deterministic …

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Application Of Genomics To Regulatory Ecological Risk Assessments For Pesticides, Steven P. Bradbury, Sigmund J. Degitz, Robert A. Hoke, Richard Brennan, Lee Ferguson, Rebecca Klaper, Laszlo Orban, David Spurgeon, Susan Tilton Jan 2008

Application Of Genomics To Regulatory Ecological Risk Assessments For Pesticides, Steven P. Bradbury, Sigmund J. Degitz, Robert A. Hoke, Richard Brennan, Lee Ferguson, Rebecca Klaper, Laszlo Orban, David Spurgeon, Susan Tilton

Steven P. Bradbury

Substantial advances in human health and ecological risk assessment have been achieved by the risk assessment community; however, challenges remain, such as providing credible scientific information on a timely, efficient basis to support decisions for industrial chemicals and pesticides. Current risk assessment data generation requirements-including animal welfare concerns and the volume, appropriateness, and cost of required data-and the large number of chemicals requiring evaluation are a challenge confronting the chemical industry, national and international regulatory agencies, and associated stakeholders (Bradbury et al. 2004). The lack of hazard data for many chemicals and the need to improve the efficiency and quality …

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Toxic Responses Of The Fish Nervous System, Steven P. Bradbury, Richard W. Carlson, Tala R. Henry, Stephanie Padilla, John Cowden Jan 2008

Toxic Responses Of The Fish Nervous System, Steven P. Bradbury, Richard W. Carlson, Tala R. Henry, Stephanie Padilla, John Cowden

Steven P. Bradbury

Few of the approximately 70,000 chemicals on the Toxic Substances Control Act inventory or the 1000 to 1600 new chemicals introduced each year in the United States have been tested for neurotoxicity to support risk assessments (NRC, 1992), even though it is estimated that 5 to 10% of them are likely to be neurotoxic. Neurotoxicity has been defined as adverse effects of physical, biological, or chemical agents on the structure or function of the nervous system in developing or adult organisms (Philbert et al., 2000). From a human health risk assessment perspective, the potential for neurotoxic effects associated with synthetic …

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Attachment Of Bacterial Indicators To Particulates In Runoff From Various Soils, Michelle L. Soupir, Saied Mostaghimi Jan 2008

Attachment Of Bacterial Indicators To Particulates In Runoff From Various Soils, Michelle L. Soupir, Saied Mostaghimi

Michelle L. Soupir

A field study was conducted to examine the fate of E. coli and enterococci transport from three bare soil types receiving cowpat treatments and develop relationships between bacterial partitioning and phosphorous and carbon transport. Particles sizes to which cells preferentially associated were also identified.

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Quantifying Total And Sustainable Agricultural Biomass Resources In South Dakota, Kurt A. Rosentrater, Russell Persyn, Dennis Todey Jun 2007

Quantifying Total And Sustainable Agricultural Biomass Resources In South Dakota, Kurt A. Rosentrater, Russell Persyn, Dennis Todey

Kurt A. Rosentrater

Conversion of biomass is considered the next major advance in biorenewable fuels, energy, and products. Wholesale conversion to biomass utilization could result in removal of current crop residues from agricultural fields or even implementation of different crops and cropping strategies (i.e., switchgrass). To date, the driver for biomass processing has been economics and limitations on the conversion of the lignocellulose. Over the last forty years significant investments and resultant changes in management practices in the agricultural sector have focused on soil and water conservation. One of the major efforts has focused on conservation-till or no-till, with the goal of retaining …

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Compression Molding Of Phenolic Resin And Corn-Based Ddgs Blends, Kurt A. Rosentrater, R. A. Tatara, S. Suraparaju Apr 2007

Compression Molding Of Phenolic Resin And Corn-Based Ddgs Blends, Kurt A. Rosentrater, R. A. Tatara, S. Suraparaju

Kurt A. Rosentrater

With the rapid growth in the ethanol fuel industry in recent years, considerable research is being devoted to optimizing the use of processing coproducts, such as distillers dried grains with solubles (DDGS), in livestock diets. Because these residues contain high fiber levels, they may be amendable to incorporation into bio-based composites. Thus, the goal of this study was to demonstrate the viability of using corn-based DDGS as a biofiller with phenolic resin, in order to produce a novel biomaterial. DDGS was blended with phenolic resin at 0, 10, 25, 50, 75, and 90%, by weight, and then compression molded at …

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