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SETP Seed Fund, Session: OPV, Sensitized, Seed (Presentation)

Description: This project supports the Solar America Initiative by: (1) Exploring the concept of improving solar cell efficiency by generating and collecting multiple electrons per absorbed photon for h{nu} > 2Eg (Multiple Exciton Generation--MEG); and (2) Developing PV cells based on colloidally-synthesized semiconductor nanocrystals (NCs) which may eventually enable inexpensive and highly-efficient devices (single absorber design can potentially exceed Shockley-Queisser limit).
Date: April 1, 2008
Creator: Ellingson, R.
Partner: UNT Libraries Government Documents Department

Biomolecular Science (Fact Sheet)

Description: A brief fact sheet about NREL Photobiology and Biomolecular Science. The research goal of NREL's Biomolecular Science is to enable cost-competitive advanced lignocellulosic biofuels production by understanding the science critical for overcoming biomass recalcitrance and developing new product and product intermediate pathways. NREL's Photobiology focuses on understanding the capture of solar energy in photosynthetic systems and its use in converting carbon dioxide and water directly into hydrogen and advanced biofuels.
Date: April 1, 2012
Partner: UNT Libraries Government Documents Department

PV Conversion Technologies, Session: OPV, Sensitized, Seed (Presentation)

Description: The NREL Sensitized Solar Cell (SSC) Core Program supports the Solar America Initiative by: (1) targeting new devices and processes for commercialization by 2015 that are less expensive, more efficient, highly reliable, and environmentally benign; (2) collaborating with DOE OS/BES to conduct basic research targeting breakthroughs in key areas, such as ultra-high efficiency and/or ultra-low cost materials and devices.
Date: April 1, 2008
Creator: Frank, A. J.
Partner: UNT Libraries Government Documents Department

Do the Defects Make it Work? Defect Engineering in ..pi.. - Conjugated Polymer Films and Their Solar Cells (Presentation)

Description: The summaries of this report are: (1) charged defects produce 10{sup 15}-10{sup 17} cm{sup -3} free carriers; (2) treatment with nucleophiles decreases p{sub f} and {sigma} while treatment with electrophiles does not change p{sub f} but increases {sigma}; (3) both treatments increase {mu}{sub p}, L{sub ex} and stability against photo-degradation; (4) charged defects can improve OPV by increasing conductivity and creating interfacial electric fields but they hurt {mu}{sub p}, L{sub ex} and chemical stability; and (5) a better way--synthesize materials without covalent defects and dope with purposely added, bound dopants.
Date: May 1, 2008
Creator: Gregg, B. A.; Wang, D.; Reese, M. O. & Kopidakis, N.
Partner: UNT Libraries Government Documents Department

Fermentation and Electrohydrogenic Approaches to Hydrogen Production (Presentation)

Description: This work describes the development of a waste biomass fermentation process using cellulose-degrading bacteria for hydrogen production. This process is then integrated with an electrohydrogenesis process via the development of a microbial electrolysis cell reactor, during which fermentation waste effluent is further converted to hydrogen to increase the total output of hydrogen from biomass.
Date: June 1, 2010
Creator: Maness, P. C.; Thammannagowda, S.; Magnusson, L. & Logan, B.
Partner: UNT Libraries Government Documents Department

Defining the Interactions of Cellobiohydrolase with Substrate through Structure Function Studies: Cooperative Research and Development Final Report, CRADA Number CRD-10-409

Description: NREL researchers will use their expertise and skilled resources in numerical computational modeling to generate structure-function relationships for improved cellulase variant enzymes to support the development of cellulases with improved performance in biomass conversion.
Date: July 1, 2013
Creator: Beckham, G. T. & Himmel, M. E.
Partner: UNT Libraries Government Documents Department

Biomass in Multifunction Crop Plants: Cooperative Research and Development Final Report, CRADA Number CRD-05-163

Description: An array of cellulase, hemicellulase, and accessory enzymes were tested for their ability to increase the conversion levels and rates of biomass to sugar after being subjected to thermochemical pretreatment. The genes were cloned by Oklahoma State University and expressed, purified, and tested at NREL. Several enzymes were noted to be effective in increasing conversion levels, however expression levels were typically very low. The overall plan was to express these enzymes in corn as a possible mechanism towards decreased recalcitrance. One enzyme, cel5A endoglucanase from Acidothermus cellulolyticus, was transformed into both tobacco and corn. The transgenic corn stover and tobacco were examined for their susceptibility to thermochemical pretreatment followed by enzymatic digestion.
Date: October 1, 2011
Creator: Decker, S. R.
Partner: UNT Libraries Government Documents Department

Understanding Enzyme Activity Using Single Molecule Tracking (Poster)

Description: This poster describes single-molecule tracking and total internal reflection fluorescence microscopy. It discusses whether the carbohydrate-binding module (CBM) moves on cellulose, how the CBM binds to cellulose, and the mechanism of cellulosome assembly.
Date: June 1, 2009
Creator: Liu, Y.-S.; Zeng, Y.; Luo, Y.; Xu, Q.; Himmel, M.; S., Smith et al.
Partner: UNT Libraries Government Documents Department

Advances in High Throughput Screening of Biomass Recalcitrance (Poster)

Description: This was a poster displayed at the Symposium. Advances on previous high throughput screening of biomass recalcitrance methods have resulted in improved conversion and replicate precision. Changes in plate reactor metallurgy, improved preparation of control biomass, species-specific pretreatment conditions, and enzymatic hydrolysis parameters have reduced overall coefficients of variation to an average of 6% for sample replicates. These method changes have improved plate-to-plate variation of control biomass recalcitrance and improved confidence in sugar release differences between samples. With smaller errors plant researchers can have a higher degree of assurance more low recalcitrance candidates can be identified. Significant changes in plate reactor, control biomass preparation, pretreatment conditions and enzyme have significantly reduced sample and control replicate variability. Reactor plate metallurgy significantly impacts sugar release aluminum leaching into reaction during pretreatment degrades sugars and inhibits enzyme activity. Removal of starch and extractives significantly decreases control biomass variability. New enzyme formulations give more consistent and higher conversion levels, however required re-optimization for switchgrass. Pretreatment time and temperature (severity) should be adjusted to specific biomass types i.e. woody vs. herbaceous. Desalting of enzyme preps to remove low molecular weight stabilizers and improved conversion levels likely due to water activity impacts on enzyme structure and substrate interactions not attempted here due to need to continually desalt and validate precise enzyme concentration and activity.
Date: June 1, 2012
Creator: Turner, G. B.; Decker, S. R.; Tucker, M. P.; Law, C.; Doeppke, C.; Sykes, R. W. et al.
Partner: UNT Libraries Government Documents Department

Feasibility Study of Anaerobic Digestion of Food Waste in St. Bernard, Louisiana. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

Description: The U.S. Environmental Protection Agency (EPA) developed the RE-Powering America's Land initiative to re-use contaminated sites for renewable energy generation when aligned with the community's vision for the site. The former Kaiser Aluminum Landfill in St. Bernard Parish, Louisiana, was selected for a feasibility study under the program. Preliminary work focused on selecting a biomass feedstock. Discussions with area experts, universities, and the project team identified food wastes as the feedstock and anaerobic digestion (AD) as the technology.
Date: January 1, 2013
Creator: Moriarty, K.
Partner: UNT Libraries Government Documents Department

NREL Discovers Novel Protein Interaction in Green Algae that Suggests New Strategies to Improve Hydrogen Photoproduction (Fact Sheet)

Description: A research team at the National Renewable Energy Laboratory (NREL) discovered a specific interaction between the protein ferredoxin - responsible for distributing reductants from photosynthesis to different metabolic pathways - and the HYDA2 hydrogenase, suggesting a role for HYDA2 in photohydrogen production.
Date: February 1, 2011
Partner: UNT Libraries Government Documents Department

Lighting Up Enzymes for Solar Hydrogen Production (Fact Sheet)

Description: Scientists at the National Renewable Energy Laboratory (NREL) have combined quantum dots, which are spherical nanoparticles that possess unique size-tunable photophysical properties, with the high substrate selectivity and fast turnover of hydrogenase enzymes to achieve light-driven hydrogen (H2) production. They found that quantum dots of cadmium telluride coated in carboxylic acids easily formed highly stable complexes with the hydrogenase and that these hybrid assemblies functioned to catalyze H2 production using the energy of sunlight.
Date: February 1, 2011
Partner: UNT Libraries Government Documents Department