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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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CROPSR is a python tool designed for genome-wide gRNA design and evaluation for CRISPR experiments, with special focus on complex genomes such as those found in energy-producing crops. CROPSR is a product of the DOE Center for Advanced Bioenergy and Bioproducts Innovation (CABBI).
The Integrable Optics Test Accelerator (IOTA) at the Fermilab Accelerator Science and Technology (FAST) Facility will attempt to demonstrate novel techniques for high current accelerators. An electron beam of 150 MeV/c momentum and a proton beam of 70 MeV/c momentum will be used for a number of experiments, including nonlinear focusing integrable optics, space charge compensation, and optical stochastic cooling. The low energy proton beam will provide a space charge dominated regime with which to investigate Hamiltonian diffusion and chaos. A non-invasive beam instrumentation device is needed to study emittance evolution and halo formation without destroying the beam. A supersonic gas jet curtain can be injected perpendicular to the proton beam, which will preserve the integrity of the beam and provide a two-dimensional turn-by-turn profile measurement. Currently, IOTA and the gas jet monitor are being built and commissioned at Fermilab.
Nb3Sn films are a promising alternative material for su-perconducting RF cavities, with proven high quality factors at medium fields and predictions for increased superheating field as well. In this contribution, we de-scribe the latest results from the Fermilab Nb3Sn SRF program. Early experiments have been focused on single cell 1.3 GHz cavities. We briefly review efforts to bring the parameters used in the coating process into a range where they produce uniform surfaces without regions showing signs of excess tin or thin/uncoated areas. We then present the latest cavity results, after modifications to the coating recipe based on feedback from film appear-ance and RF performance. These results show high Q0 at medium fields and a maximum field of ~18 MV/m.
The objective of this project was to investigate controls on induced polarization responses in porous media. The approach taken in the project was to compare electrical measurements made on mineral surfaces with atomic force microscopy (AFM) techniques to observations made at the column-scale using traditional spectral induced polarization measurements. In the project we evaluated a number of techniques for investigating the surface properties of materials, including the development of a new AFM measurement protocol that utilizes an external electric field to induce grain-scale polarizations that can be probed using a charged AFM tip. The experiments we performed focused on idealized systems (i.e., glass beads and silica gel) where we could obtain the high degree of control needed to understand how changes in the pore environment, which are determined by biogeochemical controls in the subsurface, affect mechanisms contributing to complex electrical conductivity, i.e., conduction and polarization, responses. The studies we performed can be classified into those affecting the chemical versus physical properties of the grain surface and pore space.
This research project was designed to investigate experimentally the transport properties of the 2D electrons in Si and GaAs, two prototype semiconductors, in several new physical regimes that were previously inaccessible to experiments. The research focused on the strongly correlated electron physics in the dilute density limit, where the electron potential energy to kinetic energy ratio rs>>1, and on the fractional quantum Hall effect related physics in nuclear demagnetization refrigerator temperature range on samples with new levels of purity and controlled random disorder.
Graphene is a two-dimensional structure, one atom thick, with many uses in the world of technology. It has many useful electrical properties, is a very strong and durable material, and can be used to protect different types of substances. The world would be able to use these properties to further the strength of cars, protect metals from oxidation, increase computer speeds, use to improve superconductors, and whatever future uses that scientist invent or discover. We sought to optimize the growth and transfer of graphene. We grew graphene on copper foils by heating the foil in a furnace, and having various gases flow through a tube, where the copper foil was placed. We varied some of the concentrations of gases, along with having different times for heating the copper foil, different times for graphene growth, or a combination of the two. The focus of our experiment was to specifically grow monolayer single crystal graphene, which means that we do not want multiplayers of graphene, and do not want multiple crystals growing to form a bigger crystal. Our goal was to grow large single crystals from the growth experiment. We used a few different types of transfer methods that ranged from: using heat and pressure to press the graphene on different materials, using a polymer to cover the graphene with a method to destroy the copper, but leave the graphene and polymer intact, and using a type of heat tape with a combination of varying pressures to transfer the graphene, and then destroy the copper foil. To discover if we grew graphene we used different techniques involving lasers and microscopes to take different types of measurements. Discovering the best way of growing and transferring graphene will help with managing the cost of the future uses of graphene.
Chemical reactions between mercury, a neurotoxin, and sulfur, an essential nutrient, in the environment control to a large extent the distribution and amount of mercury available for uptake by living organisms. The largest reservoir of sulfur in soils is in living, decaying, and dissolved natural organic matter. The decaying and dissolved organic matter can also coat the surfaces of minerals in the soil. Mercury (as a divalent cation) can bind to the sulfur species in the organic matter as well as to the bare mineral surfaces, but the extent of binding and release of this mercury is not well understood. The goals of the research were to investigate fundamental relationships among mercury, natural organic matter, and selected minerals to better understand specifically the fate and transport of mercury in contaminated soils downstream from the Y-12 plant along East Fork Poplar Creek, Tennessee, and more generally in any contaminated soil. The research focused on (1) experiments to quantify the uptake and release of mercury from two clay minerals in the soil, kaolinite and vermiculite, in the presence and absence of dissolved organic matter; (2) release of mercury from cinnabar under oxic and anoxic conditions; (3) characterization of the forms of mercury in the soil using synchrotron X-ray absorption spectroscopic techniques; and, (4) determination of molecular forms of mercury in the presence of natural organic matter. We also leveraged funding from the National Science Foundation to (5) evaluate published approaches for determining sulfur speciation in natural organic matter by fitting X-ray Absorption Near Edge Structure (XANES) spectra obtained at the sulfur K-edge and apply optimized fitting schemes to new measurements of sulfur speciation in a suite of dissolved organic matter samples from the International Humic Substances Society. Lastly, in collaboration with researchers at the University of Colorado and the U.S. Geological Survey in Boulder, Colorado, (6) we investigated the biogeochemical controls on the release of mercury in simulated flooding experiments using loose soils and intact soil cores from East Fork Poplar Creek.
Building cost-effective, high-performance homes that provide superior comfort, health, and durability is the goal of the U.S. Department of Energy’s (DOE’s) Zero Energy Ready Home (ZERH) program. Building America research and other innovative programs throughout the country have addressed many of the technical challenges of building to the ZERH standard. The cost-effectiveness of measure packages that result in 30% source energy savings compared to a code-compliant home have been demonstrated. However, additional challenges remain, particularly with respect to convincing production builders of the strong business case for ZERH. The Alliance for Residential Building Innovation (ARBI) team believes that the keys to successfully engaging builders and developers in the California market are to help them leverage development agreement requirements, code compliance requirements, incentives, and competitive market advantages of ZERH certification, and navigate through this process. A primary objective of this project was to gain a highly visible foothold for residential buildings that are built to the DOE ZERH specification that can be used to encourage participation by other California builders. This report briefly describes two single-family homes that were ZERH certified and focuses on the experience of working with developer Mutual Housing on a 62-unit multifamily community at the Spring Lake subdivision in Woodland, California. The Spring Lake project is expected to be the first ZERH-certified multifamily project in the country. This report discusses the challenges encountered, lessons learned, and how obstacles were overcome.
An objective of this project was to gain a highly visible foothold for residential buildings built to the U.S. Department of Energy's Zero Energy Ready Home (ZERH) specification that can be used to encourage participation by other California builders. This report briefly describes two single family homes that were ZERH-certified, and focuses on the experience of working with developer Mutual Housing on a 62 unit multi-family community at the Spring Lake subdivision in Woodland, CA. The Spring Lake project is expected to be the first ZERH certified multi-family project nationwide. This report discusses challenges encountered, lessons learned, and how obstacles were overcome.
3D printing originally known as additive manufacturing is a process of making 3 dimensional solid objects from a CAD file. This ground breaking technology is widely used for industrial and biomedical purposes such as building objects, tools, body parts and cosmetics. An important benefit of 3D printing is the cost reduction and manufacturing flexibility; complex parts are built at the fraction of the price. However, layer by layer printing of complex shapes adds error due to the surface roughness. Any such error results in poor quality products with inaccurate dimensions. The main purpose of this research is to measure the amount of printing errors for parts with different geometric shapes and to analyze them for finding optimal printing settings to minimize the error. We use a Design of Experiments framework, and focus on studying parts with cone and ellipsoid shapes. We found that the orientation and the shape of geometric shapes have significant effect on the printing error. From our analysis, we also determined the optimal orientation that gives the least printing error.
Currently, we do not have the ability to predict the hohlraum drive and symmetry without requiring ad hoc adjustments to physics models. This document describes a plan for code improvements and focused physics validation experiments.
The purpose of this paper is to present the conclusions that can be drawn from the Field Reversed Configuration (FRC) formation experiments conducted on the Pulsed High Density experiment (PHD) at the University of Washington. The experiment is ongoing. The experimental goal for this first stage of PHD was to generate a stable, high flux (>10 mWb), high energy (>10 KJ) target FRC. Such results would be adequate as a starting point for several later experiments. This work focuses on experimental implementation and the results of the first four month run. Difficulties were encountered due to the initial on-axis plasma ionization source. Flux trapping with this ionization source acting alone was insufficient to accomplish experimental objectives. Additional ionization methods were utilized to overcome this difficulty. A more ideal plasma source layout is suggested and will be explored during a forthcoming work.
NREL is developing an advanced aerobic bubble column model using Aspen Custom Modeler (ACM). The objective of this work is to integrate the new fermentor model with existing techno-economic models in Aspen Plus and Excel to establish a new methodology for guiding process design. To assist this effort, NREL has contracted Genomatica to critique and make recommendations for improving NREL's bioreactor model and large scale aerobic bioreactor design for biologically producing lipids at commercial scale. Genomatica has highlighted a few areas for improving the functionality and effectiveness of the model. Genomatica recommends using a compartment model approach with an integrated black-box kinetic model of the production microbe. We also suggest including calculations for stirred tank reactors to extend the models functionality and adaptability for future process designs. Genomatica also suggests making several modifications to NREL's large-scale lipid production process design. The recommended process modifications are based on Genomatica's internal techno-economic assessment experience and are focused primarily on minimizing capital and operating costs. These recommendations include selecting/engineering a thermotolerant yeast strain with lipid excretion; using bubble column fermentors; increasing the size of production fermentors; reducing the number of vessels; employing semi-continuous operation; and recycling cell mass.
The U.S. Department of Energy (DOE) Building Energy Codes Program launched a series of research studies in 2014 across several U.S. states to investigate typical energy efficiency practices in residential buildings and identify opportunities to reduce household utility bills. A primary goal of the study was to help document baseline practices in new single-family construction, target areas for improvement relative to the state energy code, and quantify related savings potential. This information was intended to assist states in measuring energy compliance with their codes and to identify areas of focus for future education and training initiatives. Following the original baseline studies, project teams in each state conducted a series of education, training and outreach activities aimed at improving compliance with the state residential energy code. A second baseline study was then implemented in several states with the objective of determining whether the investment in education, training and outreach programs had produced a significant and measurable change in statewide residential energy use. Through the program, DOE planned to establish a sufficient data set to represent baseline construction trends across states and detect significant changes in energy use resulting from education and training activities. The three basic phases employed were as follows: I. Pre-Study: A baseline study to identify the energy use in typical single-family residential buildings in a given state and opportunities for improving energy efficiency II. Education & Training: Education, training and outreach activities targeting issues identified through the baseline study III. Post-Study : A second study to identify the change in energy use following the education and training activities This report outlines the application of the study in the state of West Virginia with a focus on the experiences of the project team across the multi-phased approach. Data gathered through phase I has been submitted to Pacific Northwest National Laboratory (PNNL) for analysis. Findings available to date are published as PNNL technical reports on the DOE Building Energy Codes Program website with final analysis pending publication later in 2018.
The U.S. Department of Energy (DOE) Building Energy Codes Program launched a series of research studies in 2014 across several U.S. states to investigate typical energy efficiency practices in residential buildings and identify opportunities to reduce household utility bills. A primary goal of the study was to help document baseline practices in new single-family construction, target areas for improvement relative to the state energy code, and quantify related savings potential. This information was intended to assist states in measuring energy compliance with their codes and to identify areas of focus for future education and training initiatives. Following the original baseline studies, project teams in each state conducted a series of education, training and outreach activities aimed at improving compliance with the state residential energy code. A second baseline study was then implemented in each state with the objective of determining whether the investment in education, training, and outreach programs had produced a significant and measurable change in statewide residential energy use. Through the program, DOE planned to establish a sufficient data set to represent baseline construction trends across states and detect significant changes in energy use resulting from education and training activities. The three basic phases employed in the study were as follows: I. Pre-Study : A baseline study to identify the energy use in typical single-family residential buildings in a given state and opportunities for improving energy efficiency II. Education & Training : Education, training, and outreach activities targeting issues identified through the baseline study III. Post-Study : A second study to identify the change in energy use following the education and training activities This report outlines the application of the study in the states of Arkansas, Georgia, Tennessee, and Virginia with a focus on the experiences of the project team across the “Pre-Study” and “Education and Training” phases. Data gathered through Phase I has been submitted to Pacific Northwest National Laboratory (PNNL) for analysis. Findings available to date are published as PNNL technical reports on the DOE Building Energy Codes Program website with Post-Study analysis pending publication in 2019.
Boreal regions have experienced warming faster than the rest of the Earth, and the arctic ice cover has declined at a rate faster than predicted by most climate models. Uncertainties in climate projections for this region are large, in part due to the lack of observational guidance to constrain the treatment of aerosol-cloud-precipitation linkages in climate models. To remedy this shortfall, field campaigns have been conducted to collect integrated, comprehensive measurements under specific atmospheric regimes. While considerable efforts have been devoted to subtropical marine boundary-layer clouds, as well as to clouds in the stable arctic environment, very few targeted observations exist of convective boundary-layer clouds that form over open water when cold airmasses are advected off ice-covered regions or boreal continents. There is an urgent need to shed light on the dynamics and microphysical properties of clouds and precipitation in the high-latitude marine boundary layer during cold-air outbreaks. Despite the common occurrence of linear and cellular cloud patterns that typify cold-air outbreaks, little is known about the properties of these clouds; how they vary with surface, environmental, and aerosol conditions; the role of cold-air outbreaks in the global atmospheric and ocean circulation; and the accuracy of the treatment of this atmospheric regime in climate models. Thus, we proposed to conduct the Cold-Air Outbreaks in the Marine Boundary Layer Experiment (COMBLE), to focus on marine boundary-layer clouds during cold-air outbreaks. COMBLE will deploy the first ARM Mobile Facility (AMF1) and an AMF “satellite” station in the far North Atlantic in January–May 2020. COMBLE will take advantage of the synergy with several coincident campaigns, notably MOSAIC, which will characterize the source airmasses of cold-air outbreaks over the arctic ice, and (AC) 3 , which will operate several aircraft between northern Scandinavia and the MOSAIC deployment to document evolution of these airmasses. COMBLE and its sister campaigns will compose a four-member array of supersites between northern Scandinavia and the Arctic, each with profiling and in situ cloud, precipitation, radiation, and aerosol measurements. COMBLE will be guided by six science themes. The first five deal with boundary-layer convection in cold-air outbreaks: (1) the fetch-dependent mesoscale organization of clouds and precipitation, including linear and cellular convection; (2) surface heat and momentum fluxes and vertical profiles of temperature, humidity, wind, and turbulence; (3) vertical structure of clouds and precipitation; (4) the sources and sinks of aerosol, including ice-nucleating particles, and the role of cloud-active aerosol on cloud processes and radiative fluxes; and (5) the influence of these four themes on polar cyclogenesis and polar low vertical structure. The overarching sixth theme is that COMBLE will provide integrated data sets of dynamical, thermodynamic, and cloud microphysical characteristics of marine boundary-layer convection in cold-air outbreaks, including cloud and aerosol properties, that will enable constraining high-resolution numerical simulations, developing process-level understanding, and, subsequently, evaluating and improving representations of shallow convection in weather and climate models.
Several physical mechanisms have been proposed to explain the generation of S-waves from underground explosions, such as asymmetries in the source, release of tectonic pre-stress, interactions with the free-surface, spall, and heterogeneities in the Earth. An accurate description of the explosion source processes is an important step towards understanding which of these plausible mechanisms are actively contributing to the generation of S-waves and under what conditions. In this study we explore the application of the seismic moment tensor source to model far-field, low frequency (up to 6 Hz) waveform data of over-buried chemical explosions from the Source Physics Experiment, with a focus on S-wave generation and amplitude predictions. We use an inverse waveform modeling approach to estimate the source properties of the chemical explosions, and compare solutions using different velocity models. 1D and 3D subsurface velocity models are used to characterize wave propagation between the source and receiver. We also performed analysis on wavefield simulations from physic-based explosion source modeling. The analyses show scattering and phase conversion from 3D heterogonies dominate the generation of far-field, S-wave energy observed in data, and that the variability in the recovered deviatoric component of the moment tensor source model are largely a result of inadequately accounting for 3D wave propagation effects in the inversion process.
The Center for Integrated Nanotechnologies (CINT) offers world-leading scientific expertise and specialized capabilities to create, characterize, and integrate nanostructured materials at a range of length scales, from nano- to meso-scale. CINT helps scientists perform cutting-edge research in the areas of nanoscience and nanotechnology, providing FREE ACCESS for nonproprietary research. CINT facilities are open to the international research community, including government, academic, and industry researchers. One of CINT's core research areas is in-situ S/TEM experiments. Early capabilities focused on electrical and electrochemical property measurements of materials during high-resolution imaging. More recently, the staff has expanded the available techniques to include gaseous environments (ETEM), liquid-cell, mechanics, ion irradiation, laser ablation, cryogenic, heating, and air-free transfer. In-situ investigations have focused on coupled structure-property measurements on real materials, with the CINT user community expanding many of the in-situ method developments.