ABEN Masters Theses

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Methods for Ethanol Production from the Enzymatic Hydrolysis and Fermentation of Sugar Beet Pulp
(North Dakota State University, 2010) Rorick, Rachel Elizabeth
Sugar beet pulp (SBP), the residue remaining after sucrose extraction, is currently sold as an animal feed. Humans cannot digest the cellulose in the pulp unlike ruminant animals. The pulp is primarily comprised of cellulose, hemicellulose, and pectin which can be hydrolyzed with commercial enzymes into fermentable sugars such as, glucose, arabinose, galacturonic acid, xylose, and galactose. These sugars can be fermented to produce ethanol. This research tested the variation of several enzymes, enzyme loading rates, solids loading rates, and fermenting organisms to increase ethanol yields from sugar beet pulp. Several commercial enzymes (cellulases, hemicellulases, pectinases, and proteases) were tested to determine impact on SBP hydrolysis. Two commercial enzyme preparations (Viscozyme and Pectinex) were compared. Viscozyme produced the highest sugar yields because of increased cellulose hydrolysis, while Pectinex showed less cellulase activity. All enzyme treatments resulted in similar hemicellulose and pectin hydrolysis. Pretreatment with proteases reduced sugar yields from hydrolysis by 10-30% compared to hydrolysis without pretreatment. Escherichia coli K011, a genetically modified organism (GMO), and Saccharomyces cerevisiae were used to ferment SBP hydrolyzate to increase ethanol yields (g EtOH/g SBP) and concentrations (g/L). In the "Parallel" fermentation, pectinase was used to solubilize pectin and hemicellulose. After separation, the liquid stream was fermented with E. coli K011 and the high-cellulose solid fraction was fermented using S. cerevisiae and additional cellulase enzymes (Celluclast and Novozyme 188). The "Parallel" method initially produced under 0.15 g EtOH/g SBP but was improved with pH regulation to yield 0.23 g EtOH/g SBP. The separation method limited ethanol production. The ethanol yields from three additional fermentation methods ("E. coli K011 Only", "Serial", and "Reverse Serial") were compared. The "E. coli K011 Only" method was the baseline fermentation for comparison of the remaining three fermentation methods. SBP was hydrolyzed with pectinase, cellulase, and cellobiase before fermentation with E. coli K011 to yield 0.192 g ethanol/ g SBP. The total hydrolysis of the SBP limited ethanol production. The "Serial" fermentation began by solubilizing pectin and hemicellulose with pectinases. All of the flask contents were fermented with E. coli K011. The remaining cellulose-rich SBP was then hydrolyzed with cellulases and fermented by S. cerevisiae. Initial ethanol yields were under 0.15 g EtOH/g SBP but improved to 0.238 g EtOH/g SBP. Acetic acid concentrations limited ethanol production by S. cerevisiae. The "Reverse Serial" simultaneous saccharification and fermentation (SSF) started with pectinases, cellulases, cellobiases, and S. cerevisiae. Remaining arabinose and galacturonic acid were fermented with E. coli K011 to produce a peak ethanol yield of 0.299 g EtOH/g SBP. The methods approached and exceeded published results (0.277 g EtOH/g SBP) (Doran and Foster, 2000) to successfully increase ethanol yields. Ethanol concentrations were limited by high SBP moisture content and low solids loading rates.
Rapid Evaluation of Canola Lines for Cold Soak Filterability in Biodiesel
(North Dakota State University, 2010) Lin, Hongjian, M.S.
Worldwide concerns about fossil fuel depletion and energy security have recently triggered a research interest in biodiesel, which is renewable, biodegradable, and has several other advantages as an alternative to petro diesel. However, biodiesel may cause engine problems, especially fuel filter plugging, associated with its use in cold weather conditions. Trace contaminants such as glycerin, saturated monoglycerides (SMG), and soap compromise cold weather performance of biodiesel. A cold soak filtration test was recently included in the U.S. specifications for biodiesel (ASTM D 6751-09) to evaluate biodiesel cold weather performance. Canola seed has good potential to be a locally important biodiesel feedstock because of its high yield (1500 to 2200 kg/ha) and oil content (40 to 50%, Brassica napus L.), as well as a suitable fatty acid profile for good cold weather performance. For a plant breeding program evaluating canola biodiesel quality traits, rapid preparation of biodiesel samples and assessment of its quality is important. In this work, an in situ alkaline transesterification method was adopted for preparing canola biodiesel. It was found that the biodiesel yield via this method was improved by reducing seed moisture from 6.7% to 0% after oven-drying. The resulting biodiesel had qualities comparable to or better than biodiesel prepared through the conventional alkaline transesterification. Only a limited amount of seed from new canola lines is typically available in a plant breeding program; obtaining the required volume of biodiesel for evaluating cold soak filterability (300 mL) is not possible. In order to rapidly screen canola breeding lines for B 100 quality, cold soak filterability must be assessed with reduced volumes of biodiesel. Therefore, this study evaluated the impact of SMG, glycerin, and soap on cold soak filterability. Biodiesel filtration time rapidly increased to unacceptable levels and became much less reproducible when the SMG concentration was raised above 0.28%. A regression model was generated to predict the filterability of biodiesel against the concentrations of trace contaminants. A downscaled model of the filtration test with a reduced volume of biodiesel sample (25 mL) was also tested and calibrated. The in situ transesterification method saved 30% operator time compared with the conventional method. By combining the downscaled cold soak filtration test, the goal of analyzing 40 biodiesel samples/wk was achieved.
Application of SWAT for Impact Analysis of Subsurface Drainage on Streamflows in a Snow Dominated Watershed
(North Dakota State University, 2011) Rahman, Mohammed Mizanur
The wet weather pattern since the early 1990's has created two problems for the people living in the Red River Valley (RRV): (1) wet field conditions for farmers and (2) more frequent major spring floods in the Red River system. Farmers in the region are increasingly adopting subsurface drainage practice to remove excess water from their fields to mitigate the first problem. However, it is not clear whether subsurface drainage will deteriorate or mitigate the spring flood situation, the second problem. The Soil and Water Assessment Tool (SWAT) model was applied to evaluate the impacts of tile drainage on the Red River's streamflows. The model was calibrated and validated against monthly streamflows at the watershed scale and against daily tile flows at the field scale. The locations and areas of the existing and potential tile drained (PTD) areas were identified using a GIS based decision tree classification method. The existing and maximum PTD areas were found to be about 0.75 and 17.40% of the basin area, respectively. At the field scale, the range of Nash-Sutcliffe efficiency (NSE) for model calibration and validation was 0.34-0.63. At the watershed scale, the model showed satisfactory performance in simulating monthly streamflows with NSE ranging from 0.69 to 0.99, except that the model under-predicted the highest spring flood peak flows in three years. The results of modeling a 100% tiled experimental field showed that about 30-40% of water yield was produced as tile flow. Surface runoff and soil water content decreased about 34% and 19%, respectively, due to tile drainage. However, the impact of subsurface drainage on evapotranspiration (ET) and water yield was mixed. ET slightly decreased in a wet year and slightly increased in a dry year, while the pattern for water yield was opposite to that of ET. The watershed-scaled modeling results showed that a tiling rate of 0.75-5.70% would not have significant effects on the monthly average streamflows in the Red River at Fargo. For the 17.40% tiling rate, the streamflow in the Red River at Fargo might increase up to 1% in April and about 2% in Fall (September to November), while decreasing up to 5% in the remaining months. This SWAT modeling study helped to better understand the impact of subsurface drainage on the water balance and streamflows in the Red River of the North basin. The findings will also help watershed managers in making decisions for the purpose of managing agricultural drainage development in the RRV and other snow dominated watersheds around the world.
Anaerobic Co-digestion of Dairy Manure with Canola Meal
(North Dakota State University, 2011) Atandi, Eric Michieka
There has been an increase of confined animal feeding operations (CAFOs) generating large amounts of manure. When this manure is not handled properly, it generates greenhouse gases (GHGs), odors and water pollution. Anaerobic digestion (AD) is touted as an acceptable approach to address manure management and associated environmental problems. Biogas production from manure alone is limited by low volumes of biogas yield, thus it has a poor economic reputation. Co-digestion of dairy manure with other agricultural wastes has emerged as a promising strategy to enhance the economic viability of AD. Among the agricultural wastes, canola meal (a by-product from extraction of oil from canola seed) was considered as a potential candidate for co-digestion with dairy manure. The purpose of this research was to investigate the suitability and appropriate ratios of canola meal for anaerobic co-digestion with dairy manure. In this study, various proportions of canola meal: dairy manure (100:0, 10:90, 40:60, 20:80, 0:100) by volume-basis were co-digested in 0.5 L batch bioreactors at a temperature of 35±1 °c for 25 d. Two types of canola meal were used in the study; high oil content (HOC) and low oil content (LOC) canola meal with oil contents of 8.0% and 2.5%, respectively. For HOC, the total solids (TS) were high organic loading (HOL, 7.5±2% TS) and low organic loading (LOL, 4.5±2% TS). LOC trials were done at HOL only. In addition, the pretreatment of the canola meal with caustic solution and digestion at high temperature (60±2°C) were evaluated. Results from this study indicated that at HOL, canola meal is not a viable candidate for anaerobic co-digestion with manure as it lowers biogas production. Manure only digestion performed better than bioreactors augmented with canola meal. The specific methane yield was 352 L/kg VS for manure only and 84 L/kg VS for LOC canola meal only digestion. Nonetheless, at LOL, both 10% and 20% HOC canola meal resulted in increased specific methane of 535 L/kg VS and 445 L/kg VS, respectively. This is 78% and 48% higher than 300 L/kg VS obtained in manure only digestion. Hence, canola meal is beneficial in dairy manure co-digestion at LOL. At all organic loading levels, canola meal alone digestion had the lowest cumulative biogas production (0.9 L per 0.35 L bioreactor) and specific methane yield (83 L/kg VS). For HOL, the cumulative biogas yield and specific methane yield decreased as the canola meal ratio increased, while at LOL, the decrease was only noted for bioreactors with 40% canola meal. This is suspected to be caused by elevated levels of total volatile fatty acids (VF As) of more than 4000 mg/L. Two factors are suspected to impact the accumulation of VF As: the ratio of canola-to-manure in the bioreactor and the organic loading or oil content in the canola meal. In future it will be necessary to look into ways of overcoming the inhibition caused by elevated VF As.
Evaluating Standard Wet Chemistry Techniques and NIR Spectroscopic Models for Determining Composition and Potential Ethanol Yields of Multi-Species Herbaceous Bioenergy Crops
(North Dakota State University, 2011) Monona, Ewumbua Menyoli
Herbaceous perennials represent a considerable portion of potential biomass feedstocks available for the growing bioenergy industry. Their chemical composition and biomass yields, which are important in determining ethanol potential on an area and mass basis, vary with plant variety and type, environment, and management practices. Therefore, a study was conducted to assess the variability of lignin and carbohydrate content, biomass yields, and theoretical ethanol yields on an area basis among different herbaceous perennial species combinations grown in Minot (2008) and Williston (2008, 2009, and 2010), North Dakota (ND). After wet chemistry compositional analysis was done, the carbohydrate contents were used to determine theoretical ethanol potential on a mass basis. Using the dry-matter yield, the theoretical ethanol yield on an area basis was also calculated for these biomass species. Total carbohydrate content for the biomass samples in Williston and Minot varied from 45 to 61% dry basis. Analysis of Variance (ANOVA) at a= 0.05 showed that carbohydrate content varied between years and environments. Also an interaction plot shows that no biomass species had consistently higher or lower carbohydrate content in the different environments. Switchgrass (Panicum vigatum L.) grown as single species or together with other perennial grasses had higher dry-matter yield and theoretical ethanol yield potential in Williston irrigated plots while mixtures containing intermediate or tall wheatgrass species (Thinopyrum spp.) produced better yields in Minot non-irrigated plots. Variability in theoretical ethanol yield on a mass basis (3.7% coefficient of variation (CV) in Williston and 9.7% CV in Minot) was much less than the variability in dry-matter yields (27.5% CV in Williston and 14.8% CV Minot). Therefore, biomass production is much more important than composition in choosing species to grow for ethanol production. Recently, many studies have focused on developing faster methods to determine biomass composition using near infrared (NIR) spectroscopy. Other NIR models have been developed on single biomass feedstocks but a broad-based model for mixed herbaceous perennials is yet to be developed. Therefore, NIR calibration models for lignin, glucan, and xylan were developed with 65 mixed herbaceous perennial species using a DA 7200 NIR spectrometer (950 - 1,650 nm) and GRAMS statistical software. The models for lignin and xylan had R(2) values of 0.844 and 0.872, respectively, upon validation and are classified as good for quality assurance purposes while glucan model had an R(2) of 0.81 which is considered sufficient for screening. The R(2) and the root mean square error of prediction (RMSEP) results showed that it is possible to develop calibration models to predict chemical composition for mixed perennial biomass when compared with results for models developed for single feedstock by Wolfrum and Sluiter (2009) and Liu et al. (2010). Studying the variability in predicting constituents using NIR spectroscopy over time (hours and days), it was observed that the average CV was between 1.4 to 1.6%. The average CV due to repacking (presentation) alone was 1.3%. The CVs for NIR predictions ranged between 1.4 to 5.7% while for wet chemistry ranged between 3.8 to 13.5%; hence, NIR predictions were more precise than wet chemistry analysis.
Reference Evapotranspiration and Actual Evapotranspiration Measurements in Southeastern North Dakota
(North Dakota State University, 2011) Rijal, Ishara
Subsurface drainage (SSD) has been used to remove excess water from fields in the United States upper Midwest for more than a century, but only since the last decade in the Red River Basin of the North in North Dakota (ND). The water leaving from a SSD system can affect both the quality and quantity of water that flows to a surface water system. Therefore, determination of the water balance components is the first step to study the impact of SSD on water quantity, while evapotranspiration (ET), one of the most important components in the water balance, needs to be accurately measured for SSD field. A field experiment was conducted to study the water balance in SSD and undrained (having no artificial drainage system) fields in southeast ND. The field had three different water management systems: 22 ha undrained (UD), 11 ha subsurface drained, and the remaining 11 ha subsurface drained and subsurface irrigated. The ET rates were measured directly using an eddy covariance (EC) system for the SSD and UD fields. The changes in water table were monitored in 8 wells installed in both fields. Rainfall, SSD drainage volume, and soil moisture at six different depths at two locations were measured in both fields. The measurements were conducted in the growing seasons of 2009 and 2010. The ET rates were calculated for two different field crops: Com (Zea Mays) in 2009 and soybean (Glycine Max) in 2010. Crop coefficient (Kc) value was also developed using the ET measured by the EC system and the reference ET (ETref) estimated using the American Society of Civil Engineers Environmental and Water Resources Institute (ASCE-EWRI, alfalfa) method. The ETref was also estimated using the ASCE-EWRI grass and the Jensen Haise (JH) methods. The results indicated that the water table in the SSD field was lower during spring and fall than that in the UD field. The shallow water table and high soil moisture content in the spring and fall have resulted in higher ET rates in the UD field. In the summer, SSD field has favorable soil moisture at the root zone depth; the ET in the SSD field was 30% and 13% higher than that in UD field in summer 2009 and 2010, respectively. For the entire growing season, the ET in the SSD field was 15% higher compared to UD field and the difference was minimal in 2010. Though there were differences in the ET values, they were not statistically different. However, difference in magnitude of ET during summer 2009 yielded a statistical difference. During the peak growing season in July and August, the Kc values were greater in the SSD field due to healthy crops.
Combined Effect of Densification and Pretreatment on Cellulosic Ethanol Production
(North Dakota State University, 2012) Rijal, Binod
Biomass densification enhances material stability, improves flowability, and decreases both handling and transportation costs. The effect of densification, before or after pretreatment, was tested to determine the effect on cellulosic ethanol processing. Pelleting increased glucose yields of non-pretreated materials by 210% and pelleting followed by acidic and alkaline pretreatments had significant positive impacts on hydrolysis rates or yields. The increase in sugar yields was attributed predominantly to grinding of biomass within the pellet mill. The effects of low pressure densification following AFEX pretreatment were tested under several enzyme loadings both with and without prolonged storage. Densification had no adverse effects on ethanol yields from switchgrass or corn stover; however, prairie cordgrass yields were reduced by 16%. High enzyme loading (15 FPU/g-glucan) produced 15-20% higher ethanol yields than low enzyme loading (5 FPU/g-glucan). Biomass storage by 6-months did not have any negative effects on ethanol yields of AFEX-treated and densified biomass.
Evaluation of Storage Techniques to Preserve Fermentable Sugars from Sugar Beets for Ethanol Production
(North Dakota State University, 2012) Vargas-Ramirez, Juan Manuel
New sugar beet varieties may qualify as an advanced biofuel feedstock in the U.S., but new alternatives to conventional pile storage are necessary to preserve fermentable sugars and allow yearlong beet ethanol production. Fermentable sugar preservation was assessed in sugar beets stored under aerobic and anaerobic atmospheres and in raw thick juice stored at acidic (2≤ pH≤ 5) and alkaline (8≤ pH≤11) conditions. Aerobic storage of sugar beets at 4°C for 14 wk resulted in higher fermentable sugar retention (99± 4%) than at 25°C or anaerobic storage at 4° C and 25° C. Raw thick juice retained ≥ 99% of fermentable sugars at pH 3.5 and 9.5 and refractometric dissolved solids content of 64.5° Bx. The changes in fermentable sugars in raw thick juice stored for 24 wk at acidic and alkaline pH were modeled by response surface methodology. Although raw thick juice was stored successfully at acidic and alkaline pH, conditions for high-efficiency fermentation must be developed.
Non-Destructive Analysis of Single Plant Canola (Brassica Napus) Seed Using Near Infrared Spectroscopy
(North Dakota State University, 2013) Sidhu, Harjot
Near Infrared Spectroscopy (NIRS) is widely used for quantitative analysis of oilseeds in a non-destructive manner. Canola (Brassica napus) is a popular oilseed crop that is used for food and biofuel markets. Due to limited seed availability in plant breeding programs, single plant analysis is often preferred. An NIRS commercial calibration model was evaluated to predict single plant canola seed, but the results showed the need for new NIRS calibration models to predict moisture content, oil content, and fatty acid content for single plant canola seed (3 g) with minimal sample preparation. A separate NIRS calibration model was developed for glucosinolates content utilizing 20 g seed. The resulting NIRS calibration models for moisture and oil content were acceptable. However, suitable NIRS calibration models were not obtained for fatty acids and glucosinolates content due to limited constituent variability and the narrow wavelength range used to collect spectra.
Efficacy and Recovery of Cellulases Immobilized on Polymer Brushes Grafted on Silica Nanoparticles
(North Dakota State University, 2014) Samaratunga, Ashani Rangana
Cellulosic biofuels can be more economical if cellulases are recovered and reused. Cellulase and β-glucosidase were immobilized on poly(acrylic acid) brush particles. Impact of brush enzyme density on efficacy and recovery was tested. Use of free enzymes led to higher sugar concentrations than the attached for both the enzymes. Increasing cellulase density on the brushes did not impact efficacy. Higher proportions of cellobiose in hydrolyzates suggest differential attachment or efficacy of attached enzymes. Higher β-glucosidase density on brushes led to increased glucose concentrations. Density on brushes did not impact β-glucosidase recovery and [approximately] 66% was recovered. Effect of pH and temperature on hydrolysis rates and enzyme recovery was modeled. Free β-glucosidase was more stable with temperature than attached. Optimal pH for attached cellulase and β-glucosidase was 4.98 and 4.39, respectively. Recovery of β-glucosidase decreased with increasing pH and was not impacted by temperature.
Remediation of Feedlot Nutrients Runoff by Hydroponic Treatment and Electrolysis Process
(North Dakota State University, 2014) Thapa, Arjun
Intensive livestock farming in feedlot producing large amounts of manure and wastewater. Hydroponic and electrolysis treatments were studied for the remediation of nutrients from feedlot runoff. Water hyacinth, water lettuce, and sorghum were hydroponically grown in 10 L of feedlot runoff and Hoagland solution individually in plastic bucket in batches in a greenhouse. All three plants performed well in uptaking NH3-N (more than 90%) in feedlot runoff. From the feedlot runoff, TP reduction by sorghum, water hyacinth, and water lettuce ranged from 70% to 100% , 61% to 74%, and 49% to 93%, respectively. With electrolysis process, 500 mL of feedlot runoff was treated with two rectangular parallel aluminum (Al-Al), iron (Fe-Fe), or hybrid (Al-Fe) electrode at 5 V, 10 V, and 15 V DC up to 30 minutes. The TP reductions were higher (100%) followed by COD (50 % to 75%) and TN (25% to 60%) by tested electrode.
Bioavailability and Biodegradability of Dissolved Organic Nitrogen Originated From Municipal and Animal Wastewater
(North Dakota State University, 2015) Sun, Jingyi
Due to the increased concern on dissolved organic nitrogen (DON) in surface waters, it is necessary to understand the biodegradability and bioavailability of DON in point and non-point sources. In this study, algae and bacteria were applied under lab condition to undestand the impact of DON to water environment. Biodegradable DON (BDON) was determined using bacteria while bioavailable DON (ABDON) was determined using green algae Selenastrum capricornutum, Chlamydomonas reinhardtii, and Chlorella vulgaris and/or mixed culture bacteria in municipal and animal wastewaters. In both wastewater sources, ABDON efficiencies (%) for all three algae were not significantly different indicating that Chlamydomonas reinhardtii and Chlorella vulgaris can be used as a test species for nitrogen determination similar to Selenastrum capricornutum. Results showed that, the ranges of BDON and ABDON in municipal wastewaters were 50-60% and 30-77%, respectively, while the ranges of BDON and ABDON in animal wastewaters were 48-54% and 40-81%, respectively.
Extracting Carotenoids from Corn Industry Coproducts
(North Dakota State University, 2016) Cobb, Bonnie Finn
Two experiments were completed to develop methods for extracting xanthophylls from corn industry co-products, post fermentation (PF) corn oil and corn gluten meal (CGM). A solid phase extraction (SPE) method was used to fractionate a xanthophyll-rich portion of PF corn oil by varying conditioning and eluting solvents used with a diol SPE column. Conditioning with dichloromethane yielded highest xanthophyll fractionation, 86.5%. The elution solvent selected did not impact fractionation based on a two-way ANOVA. Supercritical fluid extraction of xanthohpylls from CGM was modeled using a Box-Behnken design, varying temperature, pressure, and co-solvent ratio. The optimum conditions were determined to be 40 °C, 6820 psi, and 15% co-solvent, which would extract 85.4 µg lutein/g CGM, 2.6 times more lutein than an ethanol and chloroform: dichloromethane solvent extraction. Co-solvent was the most influential extraction parameter and increasing it further could yield higher xanthophyll recovery. With further studies, this work has industrial potential.
Incorporation of Subsurface Drainage and Subirrigation Into the Checkbook Method
(North Dakota State University, 2016) Kolars, Kelsey Aaron
The highly variable climate of the Red River Valley of the North brings both flood and drought conditions, leading to an interest in subsurface water management systems (WMS). These subsurface WMS can drain excess water from the soil profile through subsurface drainage (SSD), manage water tables through controlled drainage (CD), and add additional water through subirrigation (SI). The subsurface WMS used in this study included a 21 ha CD, 17 ha CD + SI, and 16 ha undrained (control) field over a clay loam and silty clay loam soil planted with corn (2013) and soybean (2014). Both SSD and contributions from a shallow WT, through upward flux (UF), were incorporated into the Checkbook method for Irrigation Scheduling. Over the 2013 and 2014 growing seasons, daily soil moisture deficit (SMD), estimated through the modified Checkbook method (SMDSSD,UF) produced similar, if not more accurate, estimations of daily SMD.
Quantification and Characterization of Particulate Matter Generated from Unpaved Roads in the Oil Development Area of Western North Dakota
(North Dakota State University, 2016) Datta, Sumon
Western North Dakota, USA is experiencing particulate matter (PM) emissions, especially coarse (PM10) and fine (PM2.5), due to heavy traffic on unpaved roads from rapid oil development. Particulate matters may affect human and animal health, as well as soil quality. Thus, the purpose of this research was to quantify and characterize PM. Particulate matter samples were collected using miniVOL™ portable air samplers in the pre-conditioned quartz filters which were characterized using Scanning Electron Microscopy (SEM), Electron Dispersive Spectrometry (EDS). The pooled average PM¬10 concentrations varied between 30.84 ± 14.19 to 70.42 ± 38.37 µg/m3 and PM2.5 concentrations varied between 14.08 ± 6.56 µg/m3 to 19.60 ± 7.51 µg/m3. SEM and EDS analysis revealed that most of the particulates were quartz (46%), followed by silicates (36%), biogenic particles (9%), etc. Soil analysis revealed that the average concentrations of most of the metals were below the reference level except mercury and lead.
Sweet Corn Production with Different Mulches, Varieties, and Planting Dates in North Dakota
(North Dakota State University, 2016) Bye, Hannah
Sweetcorn is a high value crop that can grow almost anywhere given the right temperature conditions. In North Dakota those conditions are not always met. Using mulch increases the soil temperature. Early planting will have a higher soil temperature increase, but also creates risk from frost damage. In this study, three varieties of sweetcorn was planted with different maturity days, on four covers (black, clear, biodegradable and no mulch), with four different planting dates (from April 15 to June 1). Emergence, growth stage, plant height, leaf area index, soil and near surface air temperature, yield and sugar content was measured. The germination rate was shortened for the clear mulch by 2.6 days. Through this one year study, we can say that mulch is effective in raising soil temperature, increases early growth for 84 day variety and increases fresh yield for all mulch covers when compared to the no mulch treatment.
Use of Digital Imagery to Evaluate the Relationship Between NDVI and Crop Production Field Data at Stutsman County, North Dakota
(North Dakota State University, 2016) Pathak, Rohit
Remote sensing techniques using near infrared band and experimental field data has been already applied on experimental field conditions. However, actual field conditions can be different than experimental plots. This study aimed to test different regression model for precise mid-season corn yield prediction potential using digital imagery from Rapid Eye and actual field data and also to compare effective corn yield prediction potential of red and red edge band. In the research the concept of different management zones and effect of yield prediction potential was achieved through soil series data. Exponential and quadratic model was considerably better as compared to linear model in defining the relationship between dry yield and Normalized Difference Vegetative Index (NDVI) at V11-V14 and V20-R1 growth stages. Prominent changes in yield prediction potential for certain soil series validated the need of different management zones. V11-V12 growth stage yield prediction potential was superior to VE-V2 growth stages.
Thermal, Physico-Mechanical and Degradation Characteristics of Compatibilized Biodegradable Biopolymers and Composites
(North Dakota State University, 2017) Yatigala, Nikushi
Due to negative effects of petroleum-based plastic waste on environment, a significant consideration is given to biopolymers as sustainable alternatives. However, incompetence in technology and cost prevent the applications of biopolymers. This study evaluated the effect of compatibilizer and wood fiber filler on five types of biopolymers. To assess weathering characteristics, biocomposites were subjected to 2000 h of accelerated weathering. Biocomposites were soil buried at temperatures of 30°C and 60°C for quantifying biodegradation. Compatibilization improved thermal and physico-mechanical properties. All properties deteriorated upon weathering, but no considerable differences were observed between compatibilized and uncompatibilized composites. After soil biodegradation, weight loss and increased water absorption were observed. Biodegradation was significant after soil burial at 60°C. Compatibilized composites after 30°C soil burial showed lower biodegradation than uncompatibilized composites, but at 60°C, it was reversed. Results confirm improved properties with compatibilization without affecting UV weathering characteristics, and achieving higher biodegradation at elevated temperatures.
Infield Biomass Bales Aggregation Logistics and Equipment Track Impacted Area Evaluation
(North Dakota State University, 2017) Navaneetha Srinivasagan, Subhashree
Efficient bale stack location, infield bale logistics, and equipment track impacted area were conducted in three different studies using simulation in R. Even though the geometric median produced the best logistics, among the five mathematical grouping methods, the field middle was recommended as it was comparable and easily accessible in the field. Curvilinear method developed (8-259 ha), incorporating equipment turning (tractor: 1 and 2 bales/trip, automatic bale picker (ABP): 8-23 bales/trip, harvester, and baler), evaluated the aggregation distance, impacted area, and operation time. The harvester generated the most, followed by the baler, and the ABP the least impacted area and operation time. The ABP was considered as the most effective bale aggregation equipment compared to the tractor. Simple specific and generalized prediction models, developed for aggregation logistics, impacted area, and operation time, have performed well (0.88≤R2≤0.99). An ABP of 8 bales capacity, also capable of 11 bales/trip, was recommended.
Developing a New Powered Seed Delivery System with Constant Seed Release Speed Using Two Confronting Belts
(North Dakota State University, 2018) Ahmadi, Mojtaba
Seed delivery devices are aimed to carry seeds down to open furrow that might affect uniformity of plant stand and spacing. The objective of this study was to develop and evaluate a new seed delivery system utilizing a two-belt mechanism configuration for sunflower (Helianthus annuus). A prototype were fabricated and tested with MeterMax® Ultra Test Stand in order to evaluate the new seed delivery system. The outcomes show that dependent variables like seed population, singulation, skips, and multiples rates were not affected by planting speed levels (Pvalues > 0.05), while planting speed had a negative effect on seed spacing consistency (P-values < 0.05). In addition, due to facing broken seeds during test process, multiples rate were between 8.0 to 9.5% and consequently affected other variables as well. To improve this mechanism and avoid the systematic error that caused by broken seeds, this system should be redesigned in a single-belt form.

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