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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,189 records · Page 66
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

Characterization of novel sorghum brown midrib mutants from an EMS-mutagenized population

Reducing lignin concentration in lignocellulosic biomass can increase forage digestibility for ruminant livestock and saccharification yields of biomass for bioenergy. In sorghum ( Sorghum bicolor (L.) Moench) and several other C4 grasses, brown midrib ( bmr ) mutants have been shown to reduce lignin concentration. Putative bmr mutants isolated from an EMS-mutagenized population were characterized and classified based on their leaf midrib phenotype and allelism tests with the previously described sorghum bmr mutants bmr2 , bmr6 , and bmr12 . These tests resulted in the identification of additional alleles of bmr2 , bmr6 ,and bmr12 , and, in addition, six bmr mutants were identified that were not allelic to these previously described loci. Further allelism testing among these six bmr mutants showed that they represented four novel bmr loci. Based on this study, the number of bmr loci uncovered in sorghum has doubled. The impact of these lines on agronomic traits and lignocellulosic composition was assessed in a 2-yr field study. Most of the identified bmr lines showed reduced lignin concentration of their biomass relative to wild-type (WT). Effects of the six new bmr mutants on enzymatic saccharification of lignocellulosic materials were determined, but the amount of glucose released from the stover was similar to WT in all cases. Like bmr2 , bmr6 , and bmr12 , these mutants may affect monolignol biosynthesis and may be useful for bioenergy and forage improvement when stacked together or in combination with the three previously described bmr alleles.

09 BIOMASS FUELS↗
DOE OSTI2015

Microalgae as a feedstock for biofuel precursors and value-added products: Green fuels and golden opportunities

In this study, the prospects of biofuel production from microalgal carbohydrates and lipids coupled with greenhouse gas mitigation due to photosynthetic assimilation of CO 2 have ushered in a renewed interest in algal feedstock. Furthermore, microalgae (including cyanobacteria) have become established as commercial sources of value-added biochemicals such as polyunsaturated fatty acids and carotenoid pigments used as antioxidants in nutritional supplements and cosmetics. This article presents a comprehensive synopsis of the metabolic basis for accumulating lipids as well as applicable methods of lipid and cellulose bioconversion and final applications of these natural or refined products from microalgal biomass. For lipids, one-step in situ transesterification offers a new and more accurate approach to quantify oil content. As a complement to microalgal oil fractions, the utilization of cellulosic biomass from microalgae to produce bioethanol by fermentation, biogas by anaerobic digestion, and bio-oil by hydrothermal liquefaction are discussed. Collectively, a compendium of information spanning green renewable fuels and value-added nutritional compounds is provided.

09 BIOMASS FUELS↗
DOE OSTI2024

Data and Scripts associated with “Lambda-PFLOTRAN: Workflow for Incorporating Organic Matter Chemistry Informed by Ultra High Resolution Mass Spectrometry into Biogeochemical Modeling.”

This data package is associated with the publication “Lambda-PFLOTRAN: Workflow for Incorporating Organic Matter Chemistry Informed by Ultra High Resolution Mass Spectrometry into Biogeochemical Modeling” submitted to Geoscientific Model Development (Muller et al., 2024). In this manuscript, organic matter chemistry and thermodynamics are directly connected to reactive transport simulators through the newly developed Lambda-PFLOTRAN (Parallel Reactive Flow and Transport model) workflow tool that succinctly incorporates organic matter chemistry data generated from Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) into reaction networks to simulate aerobic respiration of the organic matter and the resulting biogeochemistry. Lambda-PFLOTRAN is a python-based workflow, executed through a Jupyter Notebook interface, that digests raw FTICR-MS data, develops a representative reaction network based on substrate-explicit thermodynamic modeling (also termed lambda modeling due to its key thermodynamic parameter λ used therein), and completes a biogeochemical simulation with the open source, reactive flow, and transport code PFLOTRAN. This data package contains Jupyter Notebook based workflows for two test cases for running biogeochemical simulations of organic matter oxidation identified by FTICR-MS. It contains four primary folders (workflow, data, src, and analysis), a file-level metadata file (Muller_2024_Lambda_PFLOTRAN_Manuscript_Data_Package_flmd.csv) that lists all the files contained in this data package with a short description of each, and a data dictionary (Muller_2024_Lambda_PFLOTRAN_Manuscript_Data_Package_dd.csv) file that describes the tabular column headers. The ‘workflow’ folder contains the Jupyter Notebook based workflows for running the lambda analysis, PFLOTRAN simulation, sensitivity analysis and parameter estimation. The ‘data’ folder contains the FTICR-MS data, initial conditions, and incubation data for test cases 1 and 2 in folders titled ‘WHONDRS’ and ‘Colloids’, respectively. The data folder also has a ‘Database’ folder containing a reaction network for bulk organic matter (assumed to be CH2O) and a general database for PFLOTRAN (hanford_rxn_network). The CH2O reaction network defines bulk organic matter oxidation. Biogeochemical simulations are completed for both the lambda binned organic matter and bulk organic matter reaction networks. The ‘hanford_rxn_network’ database includes information required for PFLTORAN simulations including ion size, molar mass, and charge of the aqueous species, gases, and minerals phases. The ‘src’ folder contains python source codes for performing lambda analysis, PFLOTRAN simulation, sensitivity analysis and parameter estimation. The ‘analysis’ folder contains outputs from the test cases 1 and 2 including lambda analysis, PFLOTRAN runs and the calibration results.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

Foliar element determination from field survey in association with the National Ecological Observatory Network Airborne Observation Platform survey, East River, Colorado 2018

The purpose of this dataset is to support research aimed at understanding the coupling between hydrologic and biogeochemical processes at watershed scale, particularly the relationship between aboveground vegetation characteristics and subsurface soil properties. These data are intended to inform and calibrate models of catchment-scale biogeochemical fluxes, including rock-derived nutrient cycling, and they were procured to address the following questions: (1) What is the distribution of vegetation characteristics across the study catchments? (2) Are foliar concentrations of rock-derived nutrients related to underlying lithology and soil availability, or are these signals masked by biotic nutrient cycling and retention processes?This data package contains foliar elemental data collected during the 2018 National Ecological Observatory Networks (NEON) Airborne Observation Platform (AOP) imaging spectroscopy and lidar surveys in Gunnison County, Colorado. Folair samples were collected across the East River, Washington Gulch, Slate River, and Coal Creek watersheds and contain a mixture of vegetation including meadow, shrub, and tree foliar samples. The samples were processed using aqua regia digestion and analyzed for elemental determination on inductively coupled plasma optical emission spectrometry (ICP-OES).The data package includes: (1) raw foliar elemental data files in CSV and PDF formats, (2) quality control certificates in PDF format, and (3) an aggregated CSV file containing all elemental measurements compiled across samples. No specialized software is required to access or use these files.

2018 National Ecological Observatory Network Campa↗
DOE OSTI2012

High pH reversed-phase chromatography with fraction concatenation for 2D proteomic analysis

Orthogonal high-resolution separations are critical for attaining improved analytical dynamic ranges of proteome measurements. Concatenated high pH reversed phase liquid chromatography affords better separations than the strong cation exchange conventionally applied for two-dimensional shotgun proteomic analysis. For example, concatenated high pH reversed phase liquid chromatography increased identification coverage for peptides (e.g., by 1.8-fold) and proteins (e.g., by 1.6-fold) in shotgun proteomics analyses of a digested human protein sample. Additional advantages of concatenated high pH RPLC include improved protein sequence coverage, simplified sample processing, and reduced sample losses, making this an attractive first dimension separation strategy for two-dimensional proteomics analyses.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2025

Distillable amine-based solvents for effective pretreatment of multiple biomass feedstocks

Exploring the potential of advanced distillable solvents as efficient biomass pretreatment agents is critical for biorefineries, enhancing fermentable sugar yields while enabling solvent recovery and recycling without suffering significant losses. Here, we employ distillable amine-based solvents for pretreating a wide range of lignocellulosic feedstocks, aiming to facilitate the industrial release of fermentable sugars from diverse feedstocks through enzymatic hydrolysis. Twenty-two diverse feedstocks, sourced from different geographical regions and representing various biomass categories, were surveyed for chemical (mainly carbohydrates and lignin) and lignin (S, G, and H units) profiles. Several solvents, including ethanolamine, ethanolammonium acetate, butylamine, butylammonium acetate, and triethylamine, were tested for the pretreatment of eight selected biomasses. Among these solvents, butylamine emerged as the most effective due to its favorable sugar release, excellent solvent removal rate, and low boiling point, facilitating solvent recovery and recycling. Extending butylamine pretreatment to all 22 feedstocks demonstrated desirable sugar yields and highly efficient solvent removal in the majority of the biomass sources tested. Agricultural residues and their mixtures showed particularly favorable sugar release. Despite minimal changes in cellulose crystallinity, XRD characterization of sorghum, poplar, and pine before and after butylamine pretreatment showed a decrease in intensity and a slight shift of certain peaks, indicating alterations in cellulose structure. Fourier-transform infrared spectroscopy and thermogravimetric analysis analyses suggested disruption of biomass linkages in hemicellulose and lignin, enhancing enzymatic digestibility. Scale-up experiments of the mixed agricultural feedstocks in a 1 L Parr reactor achieved over 90% glucose liberation and more than 99% butylamine removal, highlighting the scalability of the method. The resulting hydrolysates supported the growth of diverse bacterial and fungal strains, indicating downstream compatibility with commercial fermentation processes. This study presents butylamine as an effective, recoverable pretreatment solvent for a wide range of lignocellulosic feedstocks, offering a promising solution to key biorefinery challenges. The demonstrated scalability and compatibility with various biomass types and blends underscore its potential for industrial application, advancing sustainable biofuel and biochemical production.

biomass composition↗
DOE OSTI2015

The Effects of Hybrid Relative Maturity on Corn Stover for Ethanol Production and Biomass Composition

Full‐season corn ( Zea mays L.) hybrids take advantage of more of the growing season than shorter‐season hybrids often leading to greater grain and biomass yield. Many agronomic experiments aimed at corn stover production have been performed at forage harvest rather than later when stover is normally harvested for biofuel measurements. The objective of this research was to evaluate the influence of hybrid relative maturity (days RM) on stover ethanol production, ruminant digestibility, and biomass composition. Hybrids selected were high‐yielding commercial grain hybrids grown throughout Wisconsin and ranged from 85 to 115 d RM in 10 d RM increments during 2009, and in 5 d RM increments during 2010. Hybrids were harvested at physiological maturity or after a killing frost. Overall, stover and theoretical ethanol yields increased as RM increased at a linear rate of 0.211 Mg ha −1 RM −1 and 67.1 L ha −1 RM −1 . Stover nutritional and biomass composition improved as RM increased, but yield variability was greater than nutritional and biomass compositional variability. Increasing ethanol yields will likely occur by increasing stover yields rather than by altering stover composition. Therefore, until price premiums for stover composition are made available to farmers for ethanol production, the adoption of full‐season or longer maturing hybrids should be implemented for increased stover and ethanol yields.

Wilkens, Steve↗
DOE OSTI2016

First Harvest Timing and Nitrogen Application Rate Effects on Chemical Composition and Ethanol Yield of Switchgrass

Switchgrass ( Panicum virgatum L.) chemical composition dynamics must be evaluated if dual‐purpose use as both forage and feedstock is to be considered. This 2‐year study, conducted at the Brown Loam Branch Experiment Station, Raymond, MS, quantified first harvest timing (HT) and nitrogen (N) rate effects on forage nutritive value, feedstock chemical composition, and ethanol yield of both primary and aftermath harvests of ‘Alamo’ switchgrass. Treatments were factorial combinations of six HT (monthly intervals from May to October) and four N application rates (0, 35.7, 71.2, and 107.1 lb/acre) in a randomized complete block design. Aftermath was harvested in November. In both years, first harvest acid detergent fiber (ADF), neutral detergent fiber (NDF), lignin, cellulose, and hemicellulose concentrations of aboveground biomass, stems, and leaves increased with HT from May to October while aftermath harvest concentrations decreased with shorter regrowth after the first harvest. Stems had greater concentrations than leaf. Crude protein (CP) and in vitro dry matter digestibility (IVDMD) decreased with plant maturity and were greatest in the leaf component. Concentrations of major sugars increased with maturity and were greatest in the most mature stand in the aftermath. Ethanol yield was greatest in the least mature stands; however, ethanol production increased with maturity, largely because of greater biomass harvested. Nitrogen rate had no effect on forage nutritive value or feedstock composition in either the primary or aftermath harvests. These results provide information that can guide potential utilization of switchgrass as forage in early season and harvesting for biofuel feedstock at the end of the season.

Seepaul, Ramdeo↗
DOE OSTI2014

Modeling spatial patterns in soil arsenic to estimate natural baseline concentrations

ABSTRACT Arsenic in soil is an important public health concern. Toxicity guidelines and models based on laboratory studies (i.e., U.S. EPA’s Integrated Risk Information System) should consider natural soil As concentrations to avoid unnecessary remediation burdens on society. We used soil and stream sediment samples from the USGS National Geochemical Survey database to assess the spatial distribution of natural As in a 1.16E+5 km2 area. Samples were collected at 348 soil and 144 stream locations, providing approximately one sample for every 290 km2. Sample sites were selected to minimize the potential influence of anthropogenic inputs. Samples were processed using acid digestion of whole samples (concentrated HCl and ascorbic acid) and concentrations were measured using hydride-generation atomic absorption spectrometry. Soil As ranged from 2.0 to 45.6 mg kg-1. Geostatistical techniques were used to model and map the spatial variability of As. The mean and variance at unsampled locations were estimated using sequential Gaussian simulation. Five areas of elevated concentration (> the median of 10 mg kg-1) were identified and the relationships to geologic parent materials, glacial sedimentation patterns, and soil conditions interpreted. Our results showed As concentrations >10 mg kg-1 were common, and >20 mg kg-1 were not unusual for the central and west central portions of Ohio (USA). In contrast, concentrations <4 mg kg-1 were rare. Measured concentrations typically exceeded the soil As human generic screening levels of 0.39 mg/kg (1); the calculated value that corresponds to a cancer risk level of 1 in 1,000,000 for soil ingestion. Because the As content of Ohio soils is similar to many world soils, the USEPA generic soil screening level of 0.39 mg/kg is of little utility. A more useful and practical approach would be the uses of natural background levels. Regional soil As patterns based on geology and biogeochemistry and not political boundaries should be used for soil screening and other risk assessment determinations.

arsenic, background, mapping, geostatistics, toxic↗
DOE OSTI2019

Fate of cobalt and nickel in mackinawite during diagenetic pyrite formation

As iron sulfide mineral phases are important sedimentary sinks for naturally occurring or contaminant metals, it is important to know the fate of metals during the diagenetic transformation of primary sulfide minerals into more stable phases, such as pyrite (FeS 2 ). Furthermore, the trace metal content of pyrite has been proposed as a marine paleoredox proxy. Given the diverse low-temperature diagenetic formation pathways for pyrite, this use of pyrite requires validation. In this work, we studied nickel (Ni) and cobalt (Co) incorporation into freshly precipitated mackinawite (FeS m ), and after experimental diagenesis to pyrite (FeS 2 ) using S 0 as an oxidant at 65 °C. Metal incorporation was quantified on bulk digests using ICP-OES or ICP-AES. Bulk mineralogy was characterized with micro-X-ray diffraction (micro-XRD), documenting the transformation of mackinawite to pyrite. Epoxy grain mounts were made anoxically of mackinawite and pyrite grains. We used synchrotron-based micro-X-ray fluorescence (μXRF) to map the distribution of Co and Ni, as well as to collect multiple energy maps throughout the sulfur (S) K-edge. Iron (Fe) and S K-edge micro-X-ray absorption near edge spectroscopy (μXANES) was used to identify the oxidation state and mineralogy within the experimentally synthesized and diagenetically transformed minerals, and map end-member solid phases within the grain mounts using the multiple energy maps. Metal-free FeSm transformed to pyrite, with residual FeS m detectable. Co- and Ni-containing FeS m also transformed to pyrite, but with multiple techniques detecting FeS m as well as S 0 , implying less complete transformation to pyrite as compared to metal-free FeS m . These results indicate that Co and Ni may inhibit transformation for FeS m to pyrite, or slow it down. Cobalt concentrations in the solid diminished by 30% during pyrite transformation, indicating that pyrite Co may be a conservative tracer of seawater or porewater Co concentrations. Nickel concentrations increased several-fold after pyrite formation, suggesting that pyrite may have scavenged Ni from the dissolution of primary FeS m grains. Lastly, nickel in pyrites thus may not be a reliable proxy for seawater or porewater metal concentrations.

58 GEOSCIENCES↗
DOE OSTI2024

Factorial experiment to identify two-way interactions between temperature, harvesting period, hydraulic retention time, and light intensity that influence the biomass productivity and phosphorus removal efficiency of a microalgae–bacteria biofilm

Rotating algae biofilm reactors (RABRs) can reduce energy requirements for wastewater reclamation but require further optimization for implementation at water resource recovery facilities (WRRF). Optimizing RABR operation is challenging because conditions at WRRF change frequently, and disregarding interaction terms related to these changes can produce incorrect conclusions about RABR behavior. This study evaluated the two-way interaction and main effects of four factors on the biomass productivity and phosphorus removal efficiency of a microalgae-bacteria biofilm grown in municipal anaerobic digester centrate, with factor levels and operating conditions selected to mimic a pilot RABR at a WRRF in Utah. Two-way interactions harvesting period*light intensity (LI), harvesting period*temperature, and LI*hydraulic retention time (HRT) had significant effects on biomass productivity: at high temperature and low LI, highest biomass productivity was achieved with a 14-day harvesting period, but at medium temperature and high LI, highest biomass productivity was achieved with a 7-day harvesting period. At high HRT, highest biomass productivity occurred at low LI, but at low HRT, highest biomass productivity occurred at high LI. Phosphorus removal was strongly influenced by LI and occurred most rapidly during the first 2 days HRT, which suggests precipitation contributed significantly to phosphorus removal. These observations provide insight for further RABR optimization.

09 BIOMASS FUELS↗
DOE OSTI2011

TANK 26F SUPERNATANT AND 2F EVAPORATOR EDUCTOR PUMP SAMPLE CHARACTERIZATION RESULTS

In an effort to understand the reasons for system plugging problems in the SRS 2F evaporator, supernatant samples were retrieved from the evaporator feed tank (Tank 26F) and solids were collected from the evaporator eductor feed pump for characterization. The variable depth supernatant samples were retrieved from Tank 26F in early December of 2010 and samples were provided to SRNL and the F/H Area laboratories for analysis. Inspection and analysis of the samples at SRNL was initiated in early March of 2011. During the interim period, samples were frequently exposed to temperatures as low as 12 C with daily temperature fluctuations as high as 10 C. The temperature at the time of sample collection from the waste tank was 51 C. Upon opening the supernatant bottles at SRNL, many brown solids were observed in both of the Tank 26F supernatant samples. In contrast, no solids were observed in the supernatant samples sent to the F/H Area laboratories, where the analysis was completed within a few days after receipt. Based on these results, it is believed that the original Tank 26F supernatant samples did not contain solids, but solids formed during the interim period while samples were stored at ambient temperature in the SRNL shielded cells without direct climate control. Many insoluble solids (>11 wt. % for one sample) were observed in the Tank 26F supernatant samples after three months of storage at SRNL which would not dissolve in the supernatant solution in two days at 51 C. Characterization of these solids along with the eductor pump solids revealed the presence of sodium oxalate and clarkeite (uranyl oxyhydroxide) as major crystalline phases. Sodium nitrate was the dominant crystalline phase present in the unwashed Eductor Pump solids. Crystalline sodium nitrate may have formed during the drying of the solids after filtration or may have been formed in the Tank 26F supernatant during storage since the solution was found to be very concentrated (9-12 M Na{sup +}). Concentrated mineral acids and elevated temperature were required to dissolve all of these solids. The refractory nature of some of the solids is consistent with the presence of metal oxides such as aluminosilicates (observed as a minor phase by XRD). Characterization of the water wash solutions and the digested solids confirmed the presence of oxalate salts in both solid samples. Sulfate enrichment was also observed in the Tank 26F solids wash solution, indicating the presence of sulfate precipitates such as burkeite. OLI modeling of the Tank 26F filtered supernatant composition revealed that sodium oxalate has a very low solubility in this solution. The model predicts that the sodium oxalate solubility in the Tank 26F supernatant is only 0.0011 M at 50 C. The results indicate that the highly concentrated nature of the evaporator feed solution and the addition of oxalate anion to the waste stream each contribute to the formation of insoluble solids in the 2F evaporator system.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2011

Rapid Exploitation and Analysis of Documents

Analysts are overwhelmed with information. They have large archives of historical data, both structured and unstructured, and continuous streams of relevant messages and documents that they need to match to current tasks, digest, and incorporate into their analysis. The purpose of the READ project is to develop technologies to make it easier to catalog, classify, and locate relevant information. We approached this task from multiple angles. First, we tackle the issue of processing large quantities of information in reasonable time. Second, we provide mechanisms that allow users to customize their queries based on latent topics exposed from corpus statistics. Third, we assist users in organizing query results, adding localized expert structure over results. Forth, we use word sense disambiguation techniques to increase the precision of matching user generated keyword lists with terms and concepts in the corpus. Fifth, we enhance co-occurrence statistics with latent topic attribution, to aid entity relationship discovery. Finally we quantitatively analyze the quality of three popular latent modeling techniques to examine under which circumstances each is useful.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2012

2011 Vehicle Technologies Market Report

This report details the major trends in U.S. light-duty vehicle and medium/heavy truck markets as well as the underlying trends that caused them. This report is supported by the U.S. Department of Energy s (DOE) Vehicle Technologies Program (VTP), and, in accord with its mission, pays special attention to the progress of high-efficiency and alternative-fuel technologies. This third edition since this report was started in 2008 offers several marked improvements relative to its predecessors. Most significantly, where earlier editions of this report focused on supplying information through an examination of market drivers, new vehicle trends, and supplier data, this edition uses a different structure. After opening with a discussion of energy and economics, this report features a section each on the light-duty vehicle and heavy/medium truck markets, and concluding with a section each on technology and policy. In addition to making this sectional re-alignment, this year s edition of the report also takes a different approach to communicating information. While previous editions relied heavily on text accompanied by auxiliary figures, this third edition relies primarily on charts and graphs to communicate trends. Any accompanying text serves to introduce the trends communication by the graphic and highlight any particularly salient observations. The opening section on Energy and Economics discusses the role of transportation energy and vehicle markets on a national (and even international) scale. For example, Figures 11 through 13 discuss the connections between global oil prices and U.S. GDP, and Figures 20 and 21 show U.S. employment in the automotive sector. The following section examines Light-Duty Vehicle use, markets, manufacture, and supply chains. Figures 26 through 33 offer snapshots of major light-duty vehicle brands in the U.S. and Figures 38 through 43 examine the performance and efficiency characteristics of vehicles sold. The discussion of Medium and Heavy Trucks offers information on truck sales (Figures 58 through 61) and fuel use (Figures 64 through 66). The Technology section offers information on alternative fuel vehicles and infrastructure (Figures 68 through 77), and the Policy section concludes with information on recent, current, and near-future Federal policies like the Cash for Clunkers program (Figures 87 and 88) and the Corporate Automotive Fuel Economy standard (Figures 90 through 99) and. In total, the information contained in this report is intended to communicate a fairly complete understanding of U.S. highway transportation energy through a series of easily digestible nuggets.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2012

RENEWABLE ENERGY AND ENVIRONMENTAL SUSTAINABILITY USING BIOMASS FROM DAIRY AND BEEF ANIMAL PRODUCTION

The Texas Panhandle is regarded as the "Cattle Feeding Capital of the World", producing 42% of the fed beef cattle in the United States within a 200-mile radius of Amarillo generating more than 5 million tons of feedlot manure /year. Apart from feedlots, the Bosque River Region in Erath County, just north of Waco, Texas with about 110,000 dairy cattle in over 250 dairies, produces 1.8 million tons of manure biomass (excreted plus bedding) per year. While the feedlot manure has been used extensively for irrigated and dry land crop production, most dairies, as well as other concentrated animal feeding operations (CAFO's), the dairy farms utilize large lagoon areas to store wet animal biomass. Water runoff from these lagoons has been held responsible for the increased concentration of phosphorus and other contaminates in the Bosque River which drains into Lake Waco—the primary source of potable water for Waco's 108,500 people. The concentrated animal feeding operations may lead to land, water, and air pollution if waste handling systems and storage and treatment structures are not properly managed. Manure-based biomass (MBB) has the potential to be a source of green energy at large coal-fired power plants and on smaller-scale combustion systems at or near confined animal feeding operations. Although MBB particularly cattle biomass (CB) is a low quality fuel with an inferior heat value compared to coal and other fossil fuels, the concentration of it at large animal feeding operations can make it a viable source of fuel. The overall objective of this interdisciplinary proposal is to develop environmentally benign technologies to convert low-value inventories of dairy and beef cattle biomass into renewable energy. Current research expands the suite of technologies by which cattle biomass (CB: manure, and premature mortalities) could serve as a renewable alternative to fossil fuel. The work falls into two broad categories of research and development. Category 1 – Renewable Energy Conversion. This category addressed mostly in volume I involves developing. Thermo-chemical conversion technologies including cofiring with coal, reburn to reduce nitrogen oxide (NO, N2O, NOx, etc.) and Hg emissions and gasification to produce low-BTU gas for on-site power production in order to extract energy from waste streams or renewable resources. Category 2 – Biomass Resource Technology. This category, addressed mostly in Volume II, deals with the efficient and cost-effective use of CB as a renewable energy source (e.g. through and via aqueous-phase, anaerobic digestion or biological gasification). The investigators formed an industrial advisory panel consisting fuel producers (feedlots and dairy farms) and fuel users (utilities), periodically met with them, and presented the research results; apart from serving as dissemination forum, the PIs used their critique to red-direct the research within the scope of the tasks. The final report for the 5 to 7 year project performed by an interdisciplinary team of 9 professors is arranged in three volumes: Vol. I (edited by Kalyan Annamalai) addressing thermo-chemical conversion and direct combustion under Category 1 and Vol. II and Vol. III ( edited by J M Sweeten) addressing biomass resource Technology under Category 2. Various tasks and sub-tasks addressed in Volume I were performed by the Department of Mechanical Engineering (a part of TEES; see Volume I), while other tasks and sub-tasks addressed in Volume II and IIII were conducted by Texas AgriLife Research at Amarillo; the TAMU Biological & Agricultural Engineering Department (BAEN) College Station; and West Texas A&M University (WTAMU) (Volumes II and III). The three volume report covers the following results: fuel properties of low ash and high ash CB (particularly DB) and MB (mortality biomass and coals, non-intrusive visible infrared (NVIR) spectroscopy techniques for ash determination, dairy energy use surveys at 14 dairies in Texas and California, cofiring of low quality CB with high quality coal, emission results and ash fouling behavior, using CB as reburn fuel for NOx and Hg reduction, gasification of fuels to produce low quality gases, modeling of reburn, pilot scale test results, synthesis of engineering characterization, geographical mapping, a transportation cost study to determine potential handling and transportation systems for co-firing with coal at regional coal-fired power plants, software analyses for the design of off-site manure, pre-processing and storage systems for a typical dairy farm or beef cattle feedlot, recursive production functions/systems models for both cattle feedlots, systems modeling, stocks and flows of energy involved in the CAFO system, feedback from an Industry Advisory Committee (IAC) to the investigators on project direction and task emphasis and economics of using CB as cofiring and reburn fuel.

09 BIOMASS FUELS↗
DOE OSTI2012

RENEWABLE ENERGY AND ENVIRONMENTAL SUSTAINABILITY USING BIOMASS FROM DAIRY AND BEEF ANIMAL PRODUCTION

The Texas Panhandle is regarded as the "Cattle Feeding Capital of the World", producing 42% of the fed beef cattle in the United States within a 200-mile radius of Amarillo generating more than 5 million tons of feedlot manure/year. Apart from feedlots, the Bosque River Region in Erath County, just north of Waco, Texas with about 110,000 dairy cattle in over 250 dairies, produces 1.8 million tons of manure biomass (excreted plus bedding) per year. While the feedlot manure has been used extensively for irrigated and dry land crop production, most dairies, as well as other concentrated animal feeding operations (CAFO's), the dairy farms utilize large lagoon areas to store wet animal biomass. Water runoff from these lagoons has been held responsible for the increased concentration of phosphorus and other contaminates in the Bosque River which drains into Lake Waco -- the primary source of potable water for Waco's 108,500 people. The concentrated animal feeding operations may lead to land, water, and air pollution if waste handling systems and storage and treatment structures are not properly managed. Manure-based biomass (MBB) has the potential to be a source of green energy at large coal-fired power plants and on smaller-scale combustion systems at or near confined animal feeding operations. Although MBB particularly cattle biomass (CB) is a low quality fuel with an inferior heat value compared to coal and other fossil fuels, the concentration of it at large animal feeding operations can make it a viable source of fuel. The overall objective of this interdisciplinary proposal is to develop environmentally benign technologies to convert low-value inventories of dairy and beef cattle biomass into renewable energy. Current research expands the suite of technologies by which cattle biomass (CB: manure, and premature mortalities) could serve as a renewable alternative to fossil fuel. The work falls into two broad categories of research and development. Category 1 -- Renewable Energy Conversion. This category addressed mostly in volume I involves developing. Thermo-chemical conversion technologies including cofiring with coal, reburn to reduce nitrogen oxide (NO, N2O, NOx, etc.) and Hg emissions and gasification to produce low-BTU gas for on-site power production in order to extract energy from waste streams or renewable resources. Category 2 -- Biomass Resource Technology. This category, addressed mostly in Volume II, deals with the efficient and cost-effective use of CB as a renewable energy source (e.g. through and via aqueous-phase, anaerobic digestion or biological gasification). The investigators formed an industrial advisory panel consisting fuel producers (feedlots and dairy farms) and fuel users (utilities), periodically met with them, and presented the research results; apart from serving as dissemination forum, the PIs used their critique to re-direct the research within the scope of the tasks. The final report for the 5 to 7 year project performed by an interdisciplinary team of 9 professors is arranged in three volumes: Vol. I (edited by Kalyan Annamalai) addressing thermo-chemical conversion and direct combustion under Category 1 and Vol. II and Vol. III ( edited by J M Sweeten) addressing biomass resource Technology under Category 2. Various tasks and sub-tasks addressed in Volume I were performed by the Department of Mechanical Engineering (a part of TEES; see Volume I), while other tasks and sub-tasks addressed in Volume II and IIII were conducted by Texas AgriLife Research at Amarillo; the TAMU Biological & Agricultural Engineering Department (BAEN) College Station; and West Texas A&M University (WTAMU) (Volumes II and III). The three volume report covers the following results: fuel properties of low ash and high ash CB (particularly DB) and MB (mortality biomass and coals, non-intrusive visible infrared (NVIR) spectroscopy techniques for ash determination, dairy energy use surveys at 14 dairies in Texas and California, cofiring of low quality CB with high quality coal, emission results and ash fouling behavior, using CB as reburn fuel for NOx and Hg reduction, gasification of fuels to produce low quality gases, modeling of reburn, pilot scale test results, synthesis of engineering characterization, geographical mapping, a transportation cost study to determine potential handling and transportation systems for co-firing with coal at regional coal-fired power plants, software analyses for the design of off-site manure, pre-processing and storage systems for a typical dairy farm or beef cattle feedlot, recursive production functions/systems models for both cattle feedlots, systems modeling, stocks and flows of energy involved in the CAFO system, feedback from an Industry Advisory Committee (IAC) to the investigators on project direction and task emphasis and economics of using CB as cofiring and reburn fuel.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2012

Development of high-spatial and high-mass resolution mass spectrometric imaging (MSI) and its application to the study of small metabolites and endogenous molecules of plants

High-spatial and high-mass resolution laser desorption ionization (LDI) mass spectrometric (MS) imaging technology was developed for the attainment of MS images of higher quality containing more information on the relevant cellular and molecular biology in unprecedented depth. The distribution of plant metabolites is asymmetric throughout the cells and tissues, and therefore the increase in the spatial resolution was pursued to reveal the localization of plant metabolites at the cellular level by MS imaging. For achieving high-spatial resolution, the laser beam size was reduced by utilizing an optical fiber with small core diameter (25 μm) in a vacuum matrix-assisted laser desorption ionization-linear ion trap (vMALDI-LTQ) mass spectrometer. Matrix application was greatly improved using oscillating capillary nebulizer. As a result, single cell level spatial resolution of ~ 12 μm was achieved. MS imaging at this high spatial resolution was directly applied to a whole Arabidopsis flower and the substructures of an anther and single pollen grains at the stigma and anther were successfully visualized. MS imaging of high spatial resolution was also demonstrated to the secondary roots of Arabidopsis thaliana and a high degree of localization of detected metabolites was successfully unveiled. This was the first MS imaging on the root for molecular species. MS imaging with high mass resolution was also achieved by utilizing the LTQ-Orbitrap mass spectrometer for the direct identification of the surface metabolites on the Arabidopsis stem and root and differentiation of isobaric ions having the same nominal mass with no need of tandem mass spectrometry (MS/MS). MS imaging at high-spatial and high-mass resolution was also applied to cer1 mutant of the model system Arabidopsis thaliana to demonstrate its usefulness in biological studies and reveal associated metabolite changes in terms of spatial distribution and/or abundances compared to those of wild-type. The spatial distribution of targeted metabolites, mainly waxes and flavonoids, was systematically explored on various organs, including flowers, leaves, stems, and roots at high spatial resolution of ~ 12-50 μm and the changes in the abundance level of these metabolites were monitored on the cer1 mutant with respect to the wild-type. This study revealed the metabolic biology of CER1 gene on each individual organ level with very detailed high spatial resolution. The separate MS images of isobaric metabolites, i.e. C29 alkane vs. C28 aldehyde could be constructed on both genotypes from MS imaging at high mass resolution. This allows tracking of abundance changes for those compounds along with the genetic mutation, which is not achievable with low mass resolution mass spectrometry. This study supported previous hypothesis of molecular function of CER1 gene as aldehyde decarbonylase, especially by displaying hyper accumulation of aldehydes and C30 fatty acid and decrease in abundance of alkanes and ketones in several plant organs of cer1 mutant. The scope of analytes was further directed toward internal cell metabolites from the surface metabolites of the plant. MS profiling and imaging of internal cell metabolites were performed on the vibratome section of Arabidopsis leaf. Vibratome sectioning of the leaf was first conducted to remove the surface cuticle layer and it was followed by enzymatic treatment of the section to induce the digestion of primary cell walls, middle lamella, and expose the internal cells underneath to the surface for detection with the laser by LDI-MS. The subsequent MS imaging onto the enzymatically treated vibratome section allowed us to map the distribution of the metabolites in the internal cell layers, linolenic acid (C18:3 FA) and linoleic acid (C18:2 FA). The development of an assay for relative quantification of analytes at the single subcellular/organelle level by LDI-MS imaging was attempted and both plausibility and significant obstacles were seen. As a test system, native plant organelle, chloroplasts isolated from the spinach leaves were used and the localization of isolated chloroplasts dispersed on the target plate in low density was monitored by detecting the ion signal of chlorophyll a (Chl a) degradation products such as pheophytin a and pheophobide a by LDI-MS imaging in combination with fluorescence microscopy. The number of chloroplasts and their localization visualized in the MS image exactly matched those in the fluorescence image especially at low density, which first shows the plausibility of single-organelle level quantification of analytes by LDI-MS. The accumulation level of Chl a within a single chloroplast detected by LDI-MS was compared to the fluorescence signal on a pixel-to-pixel basis to further confirm the correlations of the accumulation levels measured by two methods. The proportional correlation was observed only for the chloroplasts which do not show the significant leakage of chlorophyll indicated by MS ion signal of Chl a degradation products and fluorescence signal, which was presumably caused by the prior fluorescence measurement before MS imaging. Further investigation is necessary to make this method more complete and develop LDI-MS imaging as an effective analytical tool to evaluate a relative accumulation of analytes of interest at the single subcellular/organelle level.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2012

Probing Product Binding in Cellulase Enzymes [Fact Sheet]

Large-scale computer simulations offer a new interpretation for the discrepancy in experimentally measured product inhibition constants in cellulase enzymes. The simulations also suggest new strategies for relieving product inhibition, which is key for the application of enzymes in the biofuels industry. Bacteria and fungi secrete enzyme cocktails consisting of processive and nonprocessive enzymes, which act synergistically to digest plant cell walls. As high-solids loadings are important for economically viable biomass conversion processes, the concentrations of glucose and cellobiose reached during enzymatic hydrolysis often cause a significant slow-down in cellulase activity through enzyme inhibition. Many studies have quantified cellulase product inhibition, but experimental measurements of product binding constants vary dramatically, and there is little consensus on the importance of this phenomenon. To provide molecular insights into cellulase product binding, scientists from the National Renewable Energy Laboratory (NREL) used computer simulation to demonstrate that the presence of cellodextrins bound in the substrate sites of cellulases, which are present during enzymatic catalysis, can increase cellobiose binding to processive cellulases by several orders of magnitude, whereas this presence has no effect on product binding in nonprocessive cellulases. These findings provide new insights into the large discrepancies reported for binding constants for cellulases. This work also suggests that catalytic engagement has an important effect on apparent inhibition constants for processive cellulases and should be taken into account to characterize product inhibition. Additionally, several computationally designed mutants of the processive cellulases are demonstrated to be able to reduce the cellobiose binding affinity, which suggests a means to engineer cellulases to improve the efficiency of biomass conversion.

09 BIOMASS FUELS↗