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At least 127 records · Page 7

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DOE OSTI2015

Levelized Cost of Energy Analysis of Marine and Hydrokinetic Reference Models: Preprint

In 2010 the U.S. Department of Energy initiated the development of six marine energy converter reference models. The reference models are point designs of well-known marine energy converters. Each device was designed to operate in a specific marine resource, instead of a generic device that can be deployed at any location. This method allows each device to be used as a benchmark for future reference model to benchmark future devices. The six designs consist of three current energy converters and three wave energy converters. The reference model project has generated both technical and economic data sets that are available in the public domain. The methodology to calculate the levelized cost of energy for the reference model project and an overall comparison of the cost of energy from these six reference-model designs are presented in this paper.

13 HYDRO ENERGY↗

DOE OSTI2025

Reference Fuel Development for Non-Aluminum Spent Nuclear Fuel Management

The Savannah River Site (SRS) L Area Facility provides for the safe receipt, storage, handling, and shipping of spent nuclear fuel (SNF) and has received more than 47,000 SNF assemblies since 1964. In order to consolidate receipt and storage analysis, L Area criticality safety has historically used several aluminum-clad “reference fuels” to establish bounding storage, handling, and cask loading limits and then applied a reactivity comparison approach to demonstrate that candidate fuels may be processed under the reference fuel limits. Currently, only aluminum-clad SNF from off-site research reactors are transferred on-site. The Accelerated Basin De-Inventory (ABD) program will begin the removal of bundled Non-Aluminum Spent Nuclear Fuel (NASNF) from the L Area disassembly basin for dissolution and disposition, which has driven the need for a non-aluminum reference fuel. This paper discusses the process and results of creating a new fictional homogenous NASNF highly enriched uranium reference fuel, “MITZ,” to be used in nuclear criticality safety evaluations for upcoming SNF disposition operations. Data demonstrating the relationship between neutron multiplication behavior and fuel spacing is generated for the new reference fuel MITZ as well as existing reference fuels representing several types of SNF assemblies.

Reference Fuel↗

DOE OSTI2025

Reference Fuel Development for Non-Aluminum Spent Nuclear Fuel Management

Reference Fuel↗

DOE OSTI2014

Reference Model 1 Scaled Geometry (RM1: Tidal Current Turbine)

Contains the Reference Model 1 (RM1) scaled scale geometry files of the Tidal Current Turbine, developed by the Reference Model Project (RMP). These scaled geometry files are saved as SolidWorks assembly, IGS, and STEP files, and require a CAD program to view. The scaled RM1 device was tested at the Saint Anthony Falls Laboratory (SAFL) at the University of Minnesota flume, details of which are described in the included journal article. The scale of the geometries included in this submission are at a 1:40 scale compared to the full scale geometry. This data was generated upon completion of the project on September 30, 2014. The Reference Model Project (RMP), sponsored by the U.S. Department of Energy (DOE), was a partnered effort to develop open-source MHK point designs as reference models (RMs) to benchmark MHK technology performance and costs, and an open-source methodology for design and analysis of MHK technologies, including models for estimating their capital costs, operational costs, and levelized costs of energy. The point designs also served as open-source test articles for university researchers and commercial technology developers. The RMP project team, led by Sandia National Laboratories (SNL), included a partnership between DOE, three national laboratories, including the National Renewable Energy Laboratory (NREL), Pacific Northwest National Laboratory (PNNL), and Oak Ridge National Laboratory (ORNL), the Applied Research Laboratory of Penn State University, and Re Vision Consulting. Reference Model 1 (RM1) is a dual variable-speed variable-pitch (VSVP) axial-flow tidal turbine device, designed for the Tacoma Narrows tidal current energy resource site in Puget Sound, Washington. RM1 comprises a monopile foundation and a crossarm assembly to mount the two rotors. The cross-arm assembly is nearly neutrally buoyant so the attached rotors can be recovered and redeployed with a minimal amount of lifting crane capacity; therefore, the design minimizes the handling requirements during deployment and recovery, which reduces overall cost in all O&M activities including access to the power conversion chain (PCC).

16 TIDAL AND WAVE POWER↗

DOE OSTI2014

Reference Model 6 Cost Breakdown (RM6: Oscillating Water Column)

Contains the Reference Model 6 (RM6) spreadsheets with the cost breakdown structure (CBS) for the levelized cost of energy (LCOE) calculations for a single RM6 device and multiple unit arrays. These spreadsheets are contained within an XLSX file and a spreadsheet editor such as Microsoft Excel is needed to open the file. This data was generated upon completion of the project on September 30, 2014. The Reference Model Project (RMP), sponsored by the U.S. Department of Energy (DOE), was a partnered effort to develop open-source MHK point designs as reference models (RMs) to benchmark MHK technology performance and costs, and an open-source methodology for design and analysis of MHK technologies, including models for estimating their capital costs, operational costs, and levelized costs of energy. The point designs also served as open-source test articles for university researchers and commercial technology developers. The RMP project team, led by Sandia National Laboratories (SNL), included a partnership between DOE, three national laboratories, including the National Renewable Energy Laboratory (NREL), Pacific Northwest National Laboratory (PNNL), and Oak Ridge National Laboratory (ORNL), the Applied Research Laboratory of Penn State University, and Re Vision Consulting. Reference Model 6 (RM6) is a Backward Bent Duct Buoy (BBDB), which is a type of oscillating water column wave energy converter. First proposed by Masuda, the BBDB design is a floating Oscillating Water Column (OWC) device that consists of an air chamber, an L-shaped duct, bow and stern buoyancy modules, and a power take-off (PTO) composed of a Wells air turbine and a generator. This L- shaped device opens to the ocean downstream from the wave propagation direction. Power is produced by the motion of the wave, which causes the ambient pressure in the air chamber to vary thereby forcing air to flow through the Wells turbine. The reference wave energy resource for RM6 was developed from site information collected near Eureka, in Humboldt County, California.

16 TIDAL AND WAVE POWER↗

DOE OSTI2014

Reference Model 5 Cost Breakdown (RM5: Oscillating Surge Flap)

Contains the Reference Model 5 (RM5) spreadsheets with the cost breakdown structure (CBS) for the levelized cost of energy (LCOE) calculations for a single RM5 device and multiple unit arrays. These spreadsheets are contained within an XLSX file and a spreadsheet editor such as Microsoft Excel is needed to open the file. This data was generated upon completion of the project on September 30, 2014. The Reference Model Project (RMP), sponsored by the U.S. Department of Energy (DOE), was a partnered effort to develop open-source MHK point designs as reference models (RMs) to benchmark MHK technology performance and costs, and an open-source methodology for design and analysis of MHK technologies, including models for estimating their capital costs, operational costs, and levelized costs of energy. The point designs also served as open-source test articles for university researchers and commercial technology developers. The RMP project team, led by Sandia National Laboratories (SNL), included a partnership between DOE, three national laboratories, including the National Renewable Energy Laboratory (NREL), Pacific Northwest National Laboratory (PNNL), and Oak Ridge National Laboratory (ORNL), the Applied Research Laboratory of Penn State University, and Re Vision Consulting. Reference Model 5 (RM5) is a type of floating, oscillating surge wave energy converter (OSWEC) that utilizes the surge motion of waves to generate electrical power. The reference wave energy resource for RM5 was measurement data from a National Data Buoy Center (NDBC) buoy near Eureka, in Humboldt County, California. The flap was designed to rotate against the supporting frame to convert wave energy into electrical power from the relative rotational motion induced by incoming waves. The RM5 design is rated at 360 kilowatts (kW), uses a flap of 25 m in width and 19 m in height (16 m in draft), and the distance from the top of the water surface piercing flap to the mean water surface (freeboard) is 1.5 m. The flap is connected to a shaft with a 3-m diameter that rotates against the supporting frame. The supporting frame is assumed to have an outer diameter of 2 m, and the total length of the device structure is 45 m. The RM5 OSWEC was designed for deep-water deployment, at depths between 50 m and 100 m, and was tension-moored to the seabed.

16 TIDAL AND WAVE POWER↗

DOE OSTI2014

Reference Model 2 Cost Breakdown (RM2: River Current Turbine)

Contains the Reference Model 2 (RM2) spreadsheets with the cost breakdown structure (CBS) for the levelized cost of energy (LCOE) calculations for a single RM2 device and multiple unit arrays. These spreadsheets are contained within an XLSX file and a spreadsheet editor such as Microsoft Excel is needed to open the file. This data was generated upon completion of the project on September 30, 2014. The Reference Model Project (RMP), sponsored by the U.S. Department of Energy (DOE), was a partnered effort to develop open-source MHK point designs as reference models (RMs) to benchmark MHK technology performance and costs, and an open-source methodology for design and analysis of MHK technologies, including models for estimating their capital costs, operational costs, and levelized costs of energy. The point designs also served as open-source test articles for university researchers and commercial technology developers. The RMP project team, led by Sandia National Laboratories (SNL), included a partnership between DOE, three national laboratories, including the National Renewable Energy Laboratory (NREL), Pacific Northwest National Laboratory (PNNL), and Oak Ridge National Laboratory (ORNL), the Applied Research Laboratory of Penn State University, and Re Vision Consulting. Reference Model 2 (RM2) is a variable speed dual-rotor cross-flow river turbine that is deployed at the water?s surface. It was designed for deployment at a reference site modeled after a reach in the Mississippi River near Baton Rouge, Louisiana. The rotors are anchored to a two-pontoon vessel platform. Surface deployment of the turbine minimizes the handling requirements during deployment and recovery and reduces overall costs for all O&M activities, including allowing for easy access to the power conversion chain (PCC). The design (two rotors per platform) also reduces the environmental footprint and associated environmental compliance costs.

16 TIDAL AND WAVE POWER↗

DOE OSTI2018

Evaluation of a Ag/Ag 2 S reference electrode with long-term stability for electrochemistry in ionic liquids

We report on a reference electrode designed for use in ionic liquids, based on a silver wire coated with silver sulfide. The reference electrode potential is determined by the concentrations of Ag + and S 2- , which are established by the solubility of the Ag 2 S coating on the Ag wire. While potential shifts of >100 mV during an experiment have been reported when using silver or platinum wire quasi-reference electrodes, the reference electrode reported here provides a stable potential over several months of experimental use. Additionally, our reference electrode can be prepared and used in a normal air atmosphere, and does not need to be assembled and used in a glovebox, or protected from light. In conclusion, the reference electrode has been characterized by voltammetry measurements of ferrocene and cobaltocenium hexafluorophosphate, and was found to slowly drift to more positive potentials at a rate of <1 mV/day for five of the six ionic liquids investigated.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2016

Correcting intensity loss errors in the absence of texture-free reference samples during pole figure measurement

Even with the use of X-ray polycapillary lenses, sample tilting during pole figure measurement results in a decrease in the recorded X-ray intensity. The magnitude of this error is affected by the sample size and/or the finite detector size. These errors can be typically corrected by measuring the intensity loss as a function of the tilt angle using a texture-free reference sample (ideally made of the same alloy as the investigated material). Since texture-free reference samples are not readily available for all alloys, the present study employs an empirical procedure to estimate the correction curve for a particular experimental configuration. It involves the use of real texture-free reference samples that pre-exist in any X-ray diffraction laboratory to first establish the empirical correlations between X-ray intensity, sample tilt and their Bragg angles and thereafter generate correction curves for any Bragg angle. It will be shown that the empirically corrected textures are in very good agreement with the experimentally corrected ones. - Highlights: •Sample tilting during X-ray pole figure measurement leads to intensity loss errors. •Texture-free reference samples are typically used to correct the pole figures. •An empirical correction procedure is proposed in the absence of reference samples. •The procedure relies on reference samples that pre-exist in any texture laboratory. •Experimentally and empirically corrected textures are in very good agreement.

36 MATERIALS SCIENCE↗

DOE OSTI2018

Selection of stable reference genes for RT-qPCR in Rhodococcus opacus PD630

Rhodococcus opacus PD630 is a gram-positive bacterium with promising attributes for the conversion of lignin into valuable fuels and chemicals. To develop an organism as a cellular factory, it is necessary to have a deep understanding of its metabolism and any heterologous pathways being expressed. For the purpose of quantifying gene transcription, reverse transcription quantitative PCR (RT-qPCR) is the gold standard due to its sensitivity and reproducibility. However, RT-qPCR requires the use of reference genes whose expression is stable across distinct growth or treatment conditions to normalize the results. Unfortunately, no in-depth analysis of stable reference genes has been conducted in Rhodococcus, inhibiting the utilization of RT-qPCR in R. opacus. In this work, ten candidate reference genes, chosen based on previously collected RNA sequencing data or literature, were examined under four distinct growth conditions using three mathematical programs (BestKeeper, Normfinder, and geNorm). Based on this analysis, the minimum number of reference genes required was found to be two, and two separate pairs of references genes were identified as optimal normalization factors for when ribosomal RNA is either present or depleted. This work represents the first validation of reference genes for Rhodococcus, providing a valuable starting point for future research.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2025

Reference Correlations for the Density and Viscosity of Molten Alkali and Alkaline Earth Fluoride Salts

While there is a significant body of literature pertaining to thermophysical property measurements of molten salts, there is often a wide degree of variability among independent measurements of the same compounds. As such, the scientific community benefits greatly from an unbiased, independent assessment of duplicate datasets, so that reference correlations which describe these thermophysical properties as functions of temperature can be determined and then commonly used by researchers, scientists, and engineers. With regard to molten fluoride compounds, a significant time has elapsed since density and viscosity reference correlations have been determined; Janz conducted the most recent effort, in 1988, to provide reference correlations for the densities and viscosities of molten fluoride compounds via the National Standard Reference Data System coordinated by the National Bureau of Standards. Since then, new data have been published for molten fluoride compounds, and a new precedent has surfaced for putting forth reference correlations that involve fitting to multiple primary datasets. In this work, reference correlations are put forth for molten alkali and alkaline earth fluoride compounds in an effort to provide updated, improved correlations for general use. For molten alkali fluoride densities, estimated uncertainties with a 95% confidence interval are summarized as follows: LiF (0.63%), NaF (0.48%), KF (0.76%), RbF (0.93%), and CsF (0.75%). For molten alkaline earth fluoride densities, an estimated uncertainty was not able to be quantified for BeF 2 because of limited data; however, estimated uncertainties with a 95% confidence interval are summarized as follows for the remaining alkaline earth fluorides: MgF 2 (1.5%), CaF 2 (0.92%), SrF 2 (1.6%), and BaF 2 (0.23%). For molten alkali fluoride viscosities, uncertainty was not able to be quantified for RbF and CsF because of limited data; however, estimated uncertainties with a 95% confidence interval are summarized as follows for the remaining alkali fluorides: LiF (4.4%), NaF (3.0%), and KF (4.0%). For molten alkaline earth fluoride viscosities, limited consistent data resulted in the recommendation of single datasets (from literature) that are deemed to be the most trustworthy based on the quality of the underlying experimental studies.

Birri, A. [Oak Ridge National Laboratory (ORNL), O↗

DOE OSTI2024

Quantum reference frames from top-down crossed products

All physical observations are made relative to a reference frame, which is a system in its own right. If the system of interest admits a group symmetry, the reference frame observing it must transform commensurately under the group to ensure the covariance of the combined system. We point out that the crossed product is a way to realize quantum reference frames from the bottom-up; adjoining a quantum reference frame and imposing constraints generates a crossed product algebra. We provide a top-down specification of crossed product algebras and show that one cannot obtain inequivalent quantum reference frames using this approach. As a remedy, we define an abstract algebra associated to the system and symmetry group built out of relational crossed product algebras associated with different choices of quantum reference frames. We term this object the G -framed algebra, and show how potentially inequivalent frames are realized within this object. We comment on this algebra’s analog of the classical Gribov problem in gauge theory, its importance in gravity where we show that it is relevant for semiclassical de Sitter and potentially beyond the semiclassical limit, and its utility for understanding the frame dependence of physical notions like observables, density states, and entropies. Published by the American Physical Society 2024

Astronomy & Astrophysics↗

DOE OSTI2012

Monte Carlo computed machine-specific correction factors for reference dosimetry of TomoTherapy static beam for several ion chambers

Purpose: To determine k{sub Q{sub m{sub s{sub r,Q{sub o}{sup f{sub m}{sub s}{sub r},f{sub o}}}}}} correction factors for machine-specific reference (msr) conditions by Monte Carlo (MC) simulations for reference dosimetry of TomoTherapy static beams for ion chambers Exradin A1SL, A12; PTW 30006, 31010 Semiflex, 31014 PinPoint, 31018 microLion; NE 2571. Methods: For the calibration of TomoTherapy units, reference conditions specified in current codes of practice like IAEA/TRS-398 and AAPM/TG-51 cannot be realized. To cope with this issue, Alfonso et al. [Med. Phys. 35, 5179-5186 (2008)] described a new formalism introducing msr factors k{sub Q{sub m{sub s{sub r,Q{sub o}{sup f{sub m}{sub s}{sub r},f{sub o}}}}}} for reference dosimetry, applicable to static TomoTherapy beams. In this study, those factors were computed directly using MC simulations for Q{sub 0} corresponding to a simplified {sup 60}Co beam in TRS-398 reference conditions (at 10 cm depth). The msr conditions were a 10 Multiplication-Sign 5 cm{sup 2} TomoTherapy beam, source-surface distance of 85 cm and 10 cm depth. The chambers were modeled according to technical drawings using the egs++ package and the MC simulations were run with the egs{sub c}hamber user code. Phase-space files used as the source input were produced using PENELOPE after simulation of a simplified {sup 60}Co beam and the TomoTherapy treatment head modeled according to technical drawings. Correlated sampling, intermediate phase-space storage, and photon cross-section enhancement variance reduction techniques were used. The simulations were stopped when the combined standard uncertainty was below 0.2%. Results: Computed k{sub Q{sub m{sub s{sub r,Q{sub o}{sup f{sub m}{sub s}{sub r},f{sub o}}}}}} values were all close to one, in a range from 0.991 for the PinPoint chamber to 1.000 for the Exradin A12 with a statistical uncertainty below 0.2%. Considering a beam quality Q defined as the TPR{sub 20,10} for a 6 MV Elekta photon beam (0.661), the additional correction k{sub Q{sub m{sub s{sub r{sub ,Q}{sup f{sub m}{sub s}{sub r}{sub ,}f{sub r}{sub e}{sub f}}}}}} to k{sub Q,Q{sub o}} defined in Alfonso et al. [Med. Phys. 35, 5179-5186 (2008)] formalism was in a range from 0.997 to 1.004.Conclusion: The MC computed factors in this study are in agreement with measured factors for chamber types already studied in literature. This work provides msr correction factors for additional chambers used in reference dosimetry. All of them were close to one (within 1%).

61 RADIATION PROTECTION AND DOSIMETRY↗

DOE OSTI2021

Identification and selection of optimal reference genes for qPCR-based gene expression analysis in Fucus distichus under various abiotic stresses

Quantitative gene expression analysis is an important tool in the scientist’s belt. The identification of evenly expressed reference genes is necessary for accurate quantitative gene expression analysis, whether by traditional RT-PCR (reverse-transcription polymerase chain reaction) or by qRT-PCR (quantitative real-time PCR; qPCR). In the Stramenopiles (the major line of eukaryotes that includes brown algae) there is a noted lack of known reference genes for such studies, largely due to the absence of available molecular tools. Here we present a set of nine reference genes (Elongation Factor 1 alpha (EF1A), Elongation Factor 2 alpha (EF2A), Elongation Factor 1 beta (EF1B), 14-3-3 Protein, Ubiquitin Conjugating Enzyme (UBCE2), Glyceraldehyde-3-phosphate Dehydrogenase (GAPDH), Actin Related Protein Complex (ARP2/3), Ribosomal Protein (40s; S23), and Actin) for the brown alga Fucus distichus . These reference genes were tested on adult sporophytes across six abiotic stress conditions (desiccation, light and temperature modification, hormone addition, pollutant exposure, nutrient addition, and wounding). Suitability of these genes as reference genes was quantitatively evaluated across conditions using standard methods and the majority of the tested genes were evaluated favorably. However, we show that normalization genes should be chosen on a condition-by-condition basis. We provide a recommendation that at least two reference genes be used per experiment, a list of recommended pairs for the conditions tested here, and a procedure for identifying a suitable set for an experimenter’s unique design. With the recent expansion of interest in brown algal biology and accompanied molecular tools development, the variety of experimental conditions tested here makes this study a valuable resource for future work in basic biology and understanding stress responses in the brown algal lineage.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2018

Solid Mechanics Code Verification: Contrasting Classical and Manufactured Reference Solutions

Verification results for Sierra/SM using inexact reference solutions have often exhibited unsatisfactory convergence behavior. With an understanding of the convergence behavior for these types of tests, one can avoid falsely attributing pathologies of the test with incorrectness of the code. Simple theoretical results highlight that for an inexact reference solution two conditions must be met to observe asymptotic convergence. These conditions, and the resulting types of convergence behaviors, are further illustrated with graphical examples depicting the exact, inexact reference, and sequence of numerical solutions as vectors (in a function space). A stress concentration problem is adopted to contrast convergence behaviors when using inexact (classical linear elastic) and exact (manufactured) reference solutions. Convergence is not initially attained with the classical solution. Convergence with the manufactured solution indicates the convergence failure with the classical reference did not result from code error and provides insight on how for this problem asymptotic convergence could be attained with the classical reference solution by modifying the computational models.

42 ENGINEERING↗

DOE OSTI2025

Fermilab PIP-II Master Oscillator and Precision Reference Line Design and Construction

The phase averaging reference line system pro- vides the RF phase reference, LO and clock sig- nals to the LLRF and other accelerator sub- systems. The PIP-II linac has RF systems at three frequencies – 162.5 MHz, 325 MHz and 650 MHz. A temperature-stabilized, low-phase- noise oscillator is used as the master oscil- lator. Phase reference signals at 162.5 MHz, 325 MHz, and 650 MHz, along with LO signals at 182.5 MHz, 345 MHz, 670 MHz and LLRF clocks at 1320 MHz and 1300 MHz, are generated in temperature-controlled RF modules at each fre- quency section. A phase reference from each module travels to the next section, where it is doubled to produce required frequencies. The reference also travels alongside the accelerating cavities in the tunnel, allowing cavity probe and reference cables to temperature track and reduce measurement errors from temperature changes or phase drift.

Syed, Ahmed [Fermilab]↗

NASA NTRS1975

Reflectance characteristics of the Viking lander camera reference test charts

Reference test charts provide radiometric, colorimetric, and spatial resolution references for the Viking lander cameras on Mars. Reflectance measurements of these references are described, including the absolute bidirectional reflectance of the radiometric references and the relative spectral reflectance of both radiometric and colorimetric references. Results show that the bidirection reflectance of the radiometric references is Lambertian to within + or - 7% for incidence angles between 20 deg and 60 deg, and that their spectral reflectance is constant with wavelength to within + or - 5% over the spectral range of the cameras. Estimated accuracy of the measurements is + or - 0.05 in relative spectral reflectance.

Wall, S. D.↗

NASA NTRS1981

Terrestrial photovoltaic performance reference conditions

The rationale behind the selection of key photovoltaic performance reference (reporting) conditions, including the standard Air Mass 1.5 solar spectrum and reference irradiance and cell temperature levels, is investigated. Besides providing a repeatable reference for performance comparisons, it is shown that the choice of reference conditions directly controls the accuracy of array energy output prediction calculations. Conclusions are drawn on the accuracy associated with present reference conditions, and recommendations are made concerning alternative reference conditions with improved accuracy.

Ross, R. G., Jr.↗