Next Generation Bipolar Plates for Automotive PEM Fuel Cells (open access)

Next Generation Bipolar Plates for Automotive PEM Fuel Cells

The results of a successful U.S. Department of Energy (DoE) funded two-year $2.9 MM program lead by GrafTech International Inc. (GrafTech) are reported and summarized. The program goal was to develop the next generation of high temperature proton exchange membrane (PEM) fuel cell bipolar plates for use in transportation fuel cell applications operating at temperatures up to 120 °C. The bipolar plate composite developed during the program is based on GrafTech’s GRAFCELL resin impregnated flexible graphite technology and makes use of a high temperature Huntsman Advanced Materials resin system which extends the upper use temperature of the composite to the DoE target. High temperature performance of the new composite is achieved with the added benefit of improvements in strength, modulus, and dimensional stability over the incumbent resin systems. Other physical properties, including thermal and electrical conductivity of the new composite are identical to or not adversely affected by the new resin system. Using the new bipolar plate composite system, machined plates were fabricated and tested in high temperature single-cell fuel cells operating at 120 °C for over 1100 hours by Case Western Reserve University. Final verification of performance was done on embossed full-size plates which were fabricated and glued into …
Date: April 15, 2010
Creator: Adrianowycz, Orest; Norley, Julian; Stuart, David J.; Flaherty, David; Wayne, Ryan; Williams, Warren et al.
Object Type: Report
System: The UNT Digital Library
Optimization of the Transport Shield for Neutrinoless Double Beta-decay Enriched Germanium (open access)

Optimization of the Transport Shield for Neutrinoless Double Beta-decay Enriched Germanium

This document presents results of an investigation of the material and geometry choice for the transport shield of germanium, the active detector material used in 76Ge neutrinoless double beta decay searches. The objective of this work is to select the optimal material and geometry to minimize cosmogenic production of radioactive isotopes in the germanium material. The design of such a shield is based on the calculation of the cosmogenic production rate of isotopes that are known to cause interfering backgrounds in 76Ge neutrinoless double beta decay searches.
Date: April 15, 2012
Creator: Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Orrell, John L.; Reid, Douglas J. & Fast, James E.
Object Type: Report
System: The UNT Digital Library
Helium measurements of pore-fluids obtained from SAFOD drillcore (open access)

Helium measurements of pore-fluids obtained from SAFOD drillcore

{sup 4}He accumulated in fluids is a well established geochemical tracer used to study crustal fluid dynamics. Direct fluid samples are not always collectable; therefore, a method to extract rare gases from matrix fluids of whole rocks by diffusion has been adapted. Helium was measured on matrix fluids extracted from sandstones and mudstones recovered during the San Andreas Fault Observatory at Depth (SAFOD) drilling in California, USA. Samples were typically collected as subcores or from drillcore fragments. Helium concentration and isotope ratios were measured 4-6 times on each sample, and indicate a bulk {sup 4}He diffusion coefficient of 3.5 {+-} 1.3 x 10{sup -8} cm{sup 2}s{sup -1} at 21 C, compared to previously published diffusion coefficients of 1.2 x 10{sup -18} cm{sup 2}s{sup -1} (21 C) to 3.0 x 10{sup -15} cm{sup 2}s{sup -1} (150 C) in the sands and clays. Correcting the diffusion coefficient of {sup 4}He{sub water} for matrix porosity ({approx}3%) and tortuosity ({approx}6-13) produces effective diffusion coefficients of 1 x 10{sup -8} cm{sup 2}s{sup -1} (21 C) and 1 x 10{sup -7} (120 C), effectively isolating pore fluid {sup 4}He from the {sup 4}He contained in the rock matrix. Model calculations indicate that <6% of helium initially …
Date: April 15, 2010
Creator: Ali, S.; Stute, M.; Torgersen, T.; Winckler, G. & Kennedy, B.M.
Object Type: Article
System: The UNT Digital Library
Distributed H{sub 2} Supply for Fuel Cell Utility Vehicles Year 6 - Activity 3.5 - Development fo a National Center for Hydrogen Technology (open access)

Distributed H{sub 2} Supply for Fuel Cell Utility Vehicles Year 6 - Activity 3.5 - Development fo a National Center for Hydrogen Technology

The Energy & Environmental Research Center (EERC) has developed a high-pressure hydrogen production system that reforms a liquid organic feedstock and water at operating pressures up to 800 bar (~12,000 psig). The advantages of this system include the elimination of energy-intensive hydrogen compression, a smaller process footprint, and the elimination of gaseous or liquid hydrogen transport. This system could also potentially enable distributed hydrogen production from centralized coal. Processes have been investigated to gasify coal and then convert the syngas into alcohol or alkanes. These alcohols and alkanes could then be easily transported in bulk to distributed high-pressure water-reforming (HPWR)-based systems to deliver hydrogen economically. The intent of this activity was to utilize the EERC’s existing HPWR hydrogen production process, previously designed and constructed in a prior project phase, as a basis to improve operational and production performance of an existing demonstration unit. Parameters to be pursued included higher hydrogen delivery pressure, higher hydrogen production rates, and the ability to refill within a 5-minute time frame.
Date: April 15, 2012
Creator: Almlie, Jay
Object Type: Report
System: The UNT Digital Library
Muon-induced backgrounds in the CUORICINO experiment (open access)

Muon-induced backgrounds in the CUORICINO experiment

To better understand the contribution of cosmic ray muons to the CUORICINO background, ten plastic scintillator detectors were installed at the CUORICINO siteand operated during the final 3 months of the experiment. From these measurements, an upper limit of 0.0021 counts/(keV.kg.yr) (95percent c.l.) was obtained on the cosmicray induced background in the neutrinoless double beta decay region of interest. The measurements were also compared to Geant4 simulations.
Date: April 15, 2010
Creator: Andreotti, E.; Arnaboldi, C.; Avignone, F. T. III; Balata, M.; Bandac, I.; Barucci, M. et al.
Object Type: Article
System: The UNT Digital Library
Ultra-High Efficiency and Low-Emissions Combustion Technology for Manufacturing Industries (open access)

Ultra-High Efficiency and Low-Emissions Combustion Technology for Manufacturing Industries

The purpose of this research was to develop and test a transformational combustion technology for high temperature furnaces to reduce the energy intensity and carbon footprint of U.S. manufacturing industries such as steel, aluminum, glass, metal casting, and petroleum refining. A new technology based on internal and/or external Flue Gas Recirculation (FGR) along with significant enhancement in flame radiation was developed. It produces "Radiative Flameless Combustion (RFC)" and offers tremendous energy efficiency and pollutant reduction benefits over and above the now popular "flameless combustion." It will reduce the energy intensity (or fuel consumption per unit system output) by more than 50% and double the furnace productivity while significantly reducing pollutants and greenhouse gas emissions (10^3 times reduction in NOx and 10 times reduction in CO & hydrocarbons and 3 times reduction in CO2). Product quality improvements are also expected due to uniform radiation, as well as, reduction in scale/dross formation is expected because of non-oxidative atmosphere. RFC is inexpensive, easy to implement, and it was successfully tested in a laboratory-scale furnace at the University of Michigan during the course of this work. A first-ever theory with gas and particulate radiation was also developed. Numerical programs were also written to design …
Date: April 15, 2013
Creator: Atreya, Arvind
Object Type: Report
System: The UNT Digital Library
Recent Developments in Dynamic Transmission Electron Microscopy (open access)

Recent Developments in Dynamic Transmission Electron Microscopy

None
Date: April 15, 2011
Creator: Browning, N D; Bonds, M A; Campbell, G H; Evans, J E; LaGrange, T; Jungjohann, K L et al.
Object Type: Article
System: The UNT Digital Library
DOE Computer Graphics Forum 2013 Site Survey (open access)

DOE Computer Graphics Forum 2013 Site Survey

None
Date: April 15, 2013
Creator: Brugger, E S; Springmeyer, R R & Laney, D E
Object Type: Report
System: The UNT Digital Library
Use of immunomagnetic separation for the detection of Desulfovibrio vulgaris from environmental samples (open access)

Use of immunomagnetic separation for the detection of Desulfovibrio vulgaris from environmental samples

Immunomagnetic separation (IMS) has proved highly efficient for recovering microorganisms from heterogeneous samples. Current investigation targeted the separation of viable cells of the sulfate-reducing bacterium, Desulfovibrio vulgaris. Streptavidin-coupled paramagnetic beads and biotin labeled antibodies raised against surface antigens of this microorganism were used to capture D. vulgaris cells in both bioreactor grown laboratory samples and from extremely low-biomass environmental soil and subsurface drilling samples. Initial studies on detection, recovery efficiency and viability for IMS were performed with laboratory grown D. vulgaris cells using various cell densities. Efficiency of cell isolation and recovery (i.e., release of the microbial cells from the beads following separation) was followed by microscopic imaging and acridine orange direct counts (AODC). Excellent recovery efficiency encouraged the use of IMS to capture Desulfovibrio spp. cells from low-biomass environmental samples. The environmental samples were obtained from a radionuclide-contaminated site in Germany and the chromium (VI)-contaminated Hanford site, an ongoing bioremediation project of the U.S. Department of Energy. Field deployable IMS technology may greatly facilitate environmental sampling and bioremediation process monitoring and enable transcriptomics and proteomics/metabolomics-based studies directly on cells collected from the field.
Date: April 15, 2011
Creator: Chakraborty, R.; Hazen, T. C.; Joyner, D. C.; Kusel, K.; Singer, M. E.; Sitte, J. et al.
Object Type: Article
System: The UNT Digital Library
Final Report on ``Theories of Strong Electron Correlations in Molecules and Solids’’ - DE-FG02-97ER45640 (open access)

Final Report on ``Theories of Strong Electron Correlations in Molecules and Solids’’ - DE-FG02-97ER45640

The PI led theoretical studies of correlated hybridization in transition metal complexes, compounds, and molecules, and of electron transport in DNA associated with nanoelectronic conformations attached to gold electrodes and in the presence of DNA repair proteins.
Date: April 15, 2013
Creator: Cox, Daniel L.
Object Type: Report
System: The UNT Digital Library
Optimal nitrogen application rates for three intensively-managed hardwood tree species in the southeastern USA. (open access)

Optimal nitrogen application rates for three intensively-managed hardwood tree species in the southeastern USA.

Forest production can be limited by nutrient and water availability, and tree species are expected to respond differently to fertilization and irrigation. Despite these common expectations, multi-species comparisons are rare, especially ones implementing a range of fertilization rates crossed with irrigation. This study compares the response of three forest hardwood species to numerous nitrogen (N) fertilization levels and water availability using a novel non-replicated technique. A range of N levels was included to determine how N affected the growth response curve, and statistical procedures for comparing these non-linear response functions are presented. We used growth and yield data to calculate the Land Expectation Value (LEV) for these intensive management treatments, and to determine the optimal growing conditions (accounting for tree productivity and grower expenses). To accomplish these objectives, we used a series of cottonwood, sycamore, and sweetgum plots that received a range of N fertilization with or without irrigation. Regression is an economical approach to define treatment responses in large-scale experiments, and we recommend >3 treatment levels so the response of any single plot does not disproportionally influence the line. The non-replicated plots showed a strong positive N response below 150 kg N ha -1 yr -1, beyond which little …
Date: April 15, 2013
Creator: Coyle, David; Aubrey, Doug P.; Siry, Jacek P.; Volfovicz-Leon, Roberto R. & Coleman, Mark D.
Object Type: Article
System: The UNT Digital Library
Shape-selective catalysts for Fischer-Tropsch chemistry : atomic layer deposition of active catalytic metals. Activity report : January 1, 2005 - September 30, 2005. (open access)

Shape-selective catalysts for Fischer-Tropsch chemistry : atomic layer deposition of active catalytic metals. Activity report : January 1, 2005 - September 30, 2005.

Argonne National Laboratory is carrying out a research program to create, prepare, and evaluate catalysts to promote Fischer-Tropsch (FT) chemistry - specifically, the reaction of hydrogen with carbon monoxide to form long-chain hydrocarbons. In addition to needing high activity, it is desirable that the catalysts have high selectivity and stability with respect to both mechanical strength and aging properties. The broad goal is to produce diesel fraction components and avoiding excess yields of both light hydrocarbons and heavy waxes. Originally the goal was to prepare shape-selective catalysts that would limit the formation of long-chain products and yet retain the active metal sites in a protected 'cage.' Such catalysts were prepared with silica-containing fractal cages. The activity was essentially the same as that of catalysts without the cages. We are currently awaiting follow-up experiments to determine the attrition strength of these catalysts. A second experimental stage was undertaken to prepare and evaluate active FT catalysts formed by atomic-layer deposition [ALD] of active components on supported membranes and particulate supports. The concept was that of depositing active metals (i.e. ruthenium, iron or cobalt) upon membranes with well defined flow channels of small diameter and length such that the catalytic activity and product …
Date: April 15, 2011
Creator: Cronauer, D. C. (Chemical Sciences and Engineering Division)
Object Type: Report
System: The UNT Digital Library
SPOCS User Guide (open access)

SPOCS User Guide

SPOCS implements a graph-based ortholog prediction method to generate a simple tab-delimited table of orthologs, and in addition, html files that provide a visualization of the ortholog/paralog relationships to which gene/protein expression metadata may be overlaid.
Date: April 15, 2013
Creator: Curtis, Darren S.; Phillips, Aaron R. & McCue, Lee Ann
Object Type: Report
System: The UNT Digital Library
Effects of nitrogen additions on above- and belowground carbon dynamics in two tropical forests (open access)

Effects of nitrogen additions on above- and belowground carbon dynamics in two tropical forests

Anthropogenic nitrogen (N) deposition is increasing rapidly in tropical regions, adding N to ecosystems that often have high background N availability. Tropical forests play an important role in the global carbon (C) cycle, yet the effects of N deposition on C cycling in these ecosystems are poorly understood. We used a field N-fertilization experiment in lower and upper elevation tropical rain forests in Puerto Rico to explore the responses of above- and belowground C pools to N addition. As expected, tree stem growth and litterfall productivity did not respond to N fertilization in either of these Nrich forests, indicating a lack of N limitation to net primary productivity (NPP). In contrast, soil C concentrations increased significantly with N fertilization in both forests, leading to larger C stocks in fertilized plots. However, different soil C pools responded to N fertilization differently. Labile (low density) soil C fractions and live fine roots declined with fertilization, while mineral-associated soil C increased in both forests. Decreased soil CO2 fluxes in fertilized plots were correlated with smaller labile soil C pools in the lower elevation forest (R2 = 0.65, p\0.05), and with lower live fine root biomass in the upper elevation forest (R2 = 0.90, …
Date: April 15, 2011
Creator: Cusack, D.; Silver, W. L.; Torn, M. S. & McDowell, W. H.
Object Type: Article
System: The UNT Digital Library
Parallel Breadth-First Search on Distributed Memory Systems (open access)

Parallel Breadth-First Search on Distributed Memory Systems

Data-intensive, graph-based computations are pervasive in several scientific applications, and are known to to be quite challenging to implement on distributed memory systems. In this work, we explore the design space of parallel algorithms for Breadth-First Search (BFS), a key subroutine in several graph algorithms. We present two highly-tuned par- allel approaches for BFS on large parallel systems: a level-synchronous strategy that relies on a simple vertex-based partitioning of the graph, and a two-dimensional sparse matrix- partitioning-based approach that mitigates parallel commu- nication overhead. For both approaches, we also present hybrid versions with intra-node multithreading. Our novel hybrid two-dimensional algorithm reduces communication times by up to a factor of 3.5, relative to a common vertex based approach. Our experimental study identifies execu- tion regimes in which these approaches will be competitive, and we demonstrate extremely high performance on lead- ing distributed-memory parallel systems. For instance, for a 40,000-core parallel execution on Hopper, an AMD Magny- Cours based system, we achieve a BFS performance rate of 17.8 billion edge visits per second on an undirected graph of 4.3 billion vertices and 68.7 billion edges with skewed degree distribution.
Date: April 15, 2011
Creator: Division, Computational Research; Buluc, Aydin & Madduri, Kamesh
Object Type: Report
System: The UNT Digital Library
Collaborative Proposal: Transforming How Climate System Models are Used: A Global, Multi-Resolution Approach (open access)

Collaborative Proposal: Transforming How Climate System Models are Used: A Global, Multi-Resolution Approach

Despite the great interest in regional modeling for both weather and climate applications, regional modeling is not yet at the stage that it can be used routinely and effectively for climate modeling of the ocean. The overarching goal of this project is to transform how climate models are used by developing and implementing a robust, efficient, and accurate global approach to regional ocean modeling. To achieve this goal, we will use theoretical and computational means to resolve several basic modeling and algorithmic issues. The first task is to develop techniques for transitioning between parameterized and high-fidelity regional ocean models as the discretization grid transitions from coarse to fine regions. The second task is to develop estimates for the error in scientifically relevant quantities of interest that provide a systematic way to automatically determine where refinement is needed in order to obtain accurate simulations of dynamic and tracer transport in regional ocean models. The third task is to develop efficient, accurate, and robust time-stepping schemes for variable spatial resolution discretizations used in regional ocean models of dynamics and tracer transport. The fourth task is to develop frequency-dependent eddy viscosity finite element and discontinuous Galerkin methods and study their performance and effectiveness …
Date: April 15, 2013
Creator: Estep, Donald
Object Type: Report
System: The UNT Digital Library
THERMOPHYSICAL PROPERTIES OF NANOPARTICLE-ENHANCED IONIC LIQUIDS HEAT TRANSFER FLUIDS (open access)

THERMOPHYSICAL PROPERTIES OF NANOPARTICLE-ENHANCED IONIC LIQUIDS HEAT TRANSFER FLUIDS

An experimental investigation was completed on nanoparticle enhanced ionic liquid heat transfer fluids as an alternative to conventional organic based heat transfer fluids (HTFs). These nanoparticle-based HTFs have the potential to deliver higher thermal conductivity than the base fluid without a significant increase in viscosity at elevated temperatures. The effect of nanoparticle morphology and chemistry on thermophysical properties was examined. Whisker shaped nanomaterials were found to have the largest thermal conductivity temperature dependence and were also less likely to agglomerate in the base fluid than spherical shaped nanomaterials.
Date: April 15, 2013
Creator: Fox, E.
Object Type: Article
System: The UNT Digital Library
Natural convection in tunnels at Yucca Mountain and impact on drift seepage (open access)

Natural convection in tunnels at Yucca Mountain and impact on drift seepage

The decay heat from radioactive waste that is to be disposed in the once proposed geologic repository at Yucca Mountain (YM) will significantly influence the moisture conditions in the fractured rock near emplacement tunnels (drifts). Additionally, large-scale convective cells will form in the open-air drifts and will serve as an important mechanism for the transport of vaporized pore water from the fractured rock in the drift center to the drift end. Such convective processes would also impact drift seepage, as evaporation could reduce the build up of liquid water at the tunnel wall. Characterizing and understanding these liquid water and vapor transport processes is critical for evaluating the performance of the repository, in terms of water-induced canister corrosion and subsequent radionuclide containment. To study such processes, we previously developed and applied an enhanced version of TOUGH2 that solves for natural convection in the drift. We then used the results from this previous study as a time-dependent boundary condition in a high-resolution seepage model, allowing for a computationally efficient means for simulating these processes. The results from the seepage model show that cases with strong natural convection effects are expected to improve the performance of the repository, since smaller relative humidity …
Date: April 15, 2010
Creator: Halecky, N.; Birkholzer, J.T. & Peterson, P.
Object Type: Article
System: The UNT Digital Library
Transport of Electron Beams with Initial Transverse-Longitudinal Correlation (open access)

Transport of Electron Beams with Initial Transverse-Longitudinal Correlation

None
Date: April 15, 2013
Creator: Harris, J R; Lewellen, J W & Poole, B R
Object Type: Article
System: The UNT Digital Library
The Potential for Energy Retrofits within the City of Sacramento's Rental Housing Inspection Program (open access)

The Potential for Energy Retrofits within the City of Sacramento's Rental Housing Inspection Program

This report presents the results of an analysis performed by Pacific Northwest National Laboratory for the City of Sacramento--under the U.S. Department of Energy’s Energy Efficiency and Renewable Energy Office of Weatherization and Intergovernmental Projects Technical Assistance Program--to help determine the potential for incorporating energy efficiency standards into the City’s existing Rental Housing Inspection Program as part of Sacramento’s efforts to create a Climate Action Plan.
Date: April 15, 2011
Creator: Iverson, Megan M.; Sande, Susan & Britt, Michelle L.
Object Type: Report
System: The UNT Digital Library
Phase II Final Report Computer Optimization of Electron Guns (open access)

Phase II Final Report Computer Optimization of Electron Guns

This program implemented advanced computer optimization into an adaptive mesh, finite element, 3D, charged particle code. The routines can optimize electron gun performance to achieve a specified current, beam size, and perveance. It can also minimize beam ripple and electric field gradients. The magnetics optimization capability allows design of coil geometries and magnetic material configurations to achieve a specified axial magnetic field profile. The optimization control program, built into the charged particle code Beam Optics Analyzer (BOA) utilizes a 3D solid modeling package to modify geometry using design tables. Parameters within the graphical user interface (currents, voltages, etc.) can be directly modified within BOA. The program implemented advanced post processing capability for the optimization routines as well as the user. A Graphical User Interface allows the user to set up goal functions, select variables, establish ranges of variation, and define performance criteria. The optimization capability allowed development of a doubly convergent multiple beam gun that could not be designed using previous techniques.
Date: April 15, 2011
Creator: Ives, R. Lawrence; Bui, Thuc; Tran, Hien; Read, Michael; Attarian, Adam & Tallis, William
Object Type: Report
System: The UNT Digital Library
Conjunctive Surface and Groundwater Management in Utah: Implications for Oil Shale and Oil Sands Development (open access)

Conjunctive Surface and Groundwater Management in Utah: Implications for Oil Shale and Oil Sands Development

Unconventional fuel development will require scarce water resources. In an environment characterized by scarcity, and where most water resources are fully allocated, prospective development will require minimizing water use and seeking to use water resources in the most efficient manner. Conjunctive use of surface and groundwater provides just such an opportunity. Conjunctive use includes two main practices: First, integrating surface water diversions and groundwater withdrawals to maximize efficiency and minimize impacts on other resource users and ecological processes. Second, conjunctive use includes capturing surplus or unused surface water and injecting or infiltrating that water into groundwater aquifers in order to increase recharge rates. Conjunctive management holds promise as a means of addressing some of the West's most intractable problems. Conjunctive management can firm up water supplies by more effectively capturing spring runoff and surplus water, and by integrating its use with groundwater withdrawals; surface and groundwater use can be further integrated with managed aquifer recharge projects. Such integration can maximize water storage and availability, while simultaneously minimizing evaporative loss, reservoir sedimentation, and surface use impacts. Any of these impacts, if left unresolved, could derail commercial-scale unconventional fuel development. Unconventional fuel developers could therefore benefit from incorporating conjunctive use into their …
Date: April 15, 2012
Creator: Keiter, Robert; Ruple, John; Tanana, Heather & Holt, Rebecca
Object Type: Report
System: The UNT Digital Library
Characterizing Hydrogen Storage Media: Understanding the Interior Pore Structure of a Cu3BTC2 Metal-Organic Framework Infiltrated with NaAlH4 (open access)

Characterizing Hydrogen Storage Media: Understanding the Interior Pore Structure of a Cu3BTC2 Metal-Organic Framework Infiltrated with NaAlH4

Preliminary results support the nano-confinement of sodium alanate within the pores of a Cu{sub 3}BTC{sub 2} MOF substrate. Increased {sup 1}H and {sup 27}Al NMR T{sub 1} relaxation rates indicate a close proximity of infiltrated sodium alante to the paramagnetic Cu{sup 2+} ions on the BTC paddlewheel units. This is in support of the theory that an interaction due to the electronegative framework with the sodium alanate facilitates thermodynamically-favorable hydrogen adsorption and desorption. Further studies can elucidate the local electronic environment of the sodium ions, further supporting a charge-transfer mechanism as the driving force for thermodynamically-favorable hydrogen adsorption and desorption.
Date: April 15, 2010
Creator: Kirmiz, A; Bhakta, R K; Allendorf, M D; Majzoub, E H; Behrens, R & Herberg, J
Object Type: Article
System: The UNT Digital Library
Final Harvest of Above-Ground Biomass and Allometric Analysis of the Aspen FACE Experiment (open access)

Final Harvest of Above-Ground Biomass and Allometric Analysis of the Aspen FACE Experiment

The Aspen FACE experiment, located at the US Forest Service Harshaw Research Facility in Oneida County, Wisconsin, exposes the intact canopies of model trembling aspen forests to increased concentrations of atmospheric CO2 and O3. The first full year of treatments was 1998 and final year of elevated CO2 and O3 treatments is scheduled for 2009. This proposal is to conduct an intensive, analytical harvest of the above-ground parts of 24 trees from each of the 12, 30 m diameter treatment plots (total of 288 trees) during June, July & August 2009. This above-ground harvest will be carefully coordinated with the below-ground harvest proposed by D.F. Karnosky et al. (2008 proposal to DOE). We propose to dissect harvested trees according to annual height growth increment and organ (main stem, branch orders, and leaves) for calculation of above-ground biomass production and allometric comparisons among aspen clones, species, and treatments. Additionally, we will collect fine root samples for DNA fingerprinting to quantify biomass production of individual aspen clones. This work will produce a thorough characterization of above-ground tree and stand growth and allocation above ground, and, in conjunction with the below ground harvest, total tree and stand biomass production, allocation, and allometry.
Date: April 15, 2013
Creator: Kubiske, Mark E.
Object Type: Report
System: The UNT Digital Library