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

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At least 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Chemical genetics to examine cellulose biosynthesis

Long-term efforts to decode plant cellulose biosynthesis via molecular genetics and biochemical strategies are being enhanced by the ever-expanding scale of omics technologies. An alternative approach to consider are the prospects for inducing change in plant metabolism using exogenously supplied chemical ligands. Cellulose biosynthesis inhibitors (CBIs) have been identified among known herbicides, during diverse combinatorial chemical libraries screens, and natural chemical screens from microbial agents. In this review, we summarize the current knowledge of the inhibitory effects of CBIs and further group them by how they influence fluorescently tagged cellulose synthase A proteins. Additional attention is paid to the continuing development of the CBI toolbox to explore the cell biology and genetic mechanisms underpinning effector molecule activity.

09 BIOMASS FUELS↗
DOE OSTI2023

Nonlinear control of safety factor gradient in tokamaks using spatially variable electron cyclotron current drives

Active control of plasma properties may be necessary to achieve stable operation of next-generation tokamaks over large time scales. Such control algorithms can regulate the plasma properties to avoid the onset of magnetohydrodynamic (MHD) instabilities. For instance, the global and local properties of the safety factor profile are linked to the onset of neoclassical tearing modes (NTMs). This work proposes a model-based control approach for deterring/delaying NTMs through active modulation of one of the safety factor properties - the gradient of the safety factor profile at a particular rational safety factor surface. In particular, a novel control-oriented model for the local safety factor gradient is developed. The nonlinear control model is governed by a nonautonomous ordinary differential equation that accounts for a given rational safety factor surface’s spatial variation over time. Further, to improve the controllability of the spatially evolving parameter, the control model treats ECH&CD positions, along with noninductive powers, as controllable variables. A nonlinear control algorithm based on feedback linearization with optimization is synthesized to achieve the objective of regulating the safety factor gradient around a given target. The proposed algorithm allocates optimal ECH&CD positions, in addition to auxiliary powers, at each time instant as the rational safety factor surface drifts to locations with a low control authority. Stability guarantees of the proposed control law are also discussed in this work. The proposed algorithm is tested for a DIII-D tokamak scenario in nonlinear simulations carried out using the Control Oriented Transport SIMulator (COTSIM). Both fixed and moving ECH&CD cases are studied, and their outcomes are compared. Simulation results demonstrate that enthusiastic regulation of the safety factor gradient can be achieved during the ramp-up and flat-top phases of tokamak operation in both fixed and moving ECH&CD cases. However, real-time updates of ECH&CD positions can prevent the saturation of auxiliary powers.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2023

Metaoptics Enabled Multifunctional Imaging

Despite the fact that most microorganisms occupy two- and three-dimensional space in heterogeneous arrangements and in proximity to other microorganisms of different species, much of our current knowledge about their metabolic processes is derived from homogenizing, then analyzing, the chemical content of cultures containing a single microbial species. This project addressed this fundamental dichotomy by developing a set of optical imaging principles combining multiple new technologies. The imaging strategies developed in this project combine metaoptics structures with active in situ nanoscale control of the chemical environment and applied them to a microbial system, Myxococcus xanthus, with particular relevance to the DoE mission. The combination of metaoptical architectures and nanoscale control over the molecular environment enables: (a) precise control over the electromagnetic (EM) field at length scales smaller than the wavelength of light; (b) control of the interaction of the EM field with critical molecular systems in DOE relevant microbes; (c) control over the chemical environment – especially the presence and quantity of reactive oxygen species (ROS) that can affect redox homeostasis; and (d) the ability to ask new kinds of questions not accessible to ‘omics’ approaches or standard methods of biological imaging. These capabilities are applicable to detailed studies of metabolic pathways in microbes and to lignocellulosic biomass deconstruction. To accomplish these objectives, we pursued two over-arching technical goals: (1) the development of new metaoptics-enabled approaches to imaging and spectroscopic characterization; and (2) the development of tools to control the chemical environment of a microbial sample with nanometer-scale precision. Goal 1 was addressed through the design, fabrication, and characterization of new metasurfaces capable of super-resolution imaging through extreme confinement of the optical field. Goal 2 was addressed by controlling the redox potential on the nanoscale in microbial communities and characterizing their effect on intrinsic bacterial fluorophores which act as molecular sentinels and through characterization of soluble factors secreted by Myxococcus xanthus by confocal Raman imaging. The optical imaging/sensing approaches developed here make it possible to use these powerful new imaging and sensing modalities in metabolic studies by making it possible to visualize and track the spatial and temporal expression patterns of natural or engineered pathways in microorganisms.

09 BIOMASS FUELS↗
DOE OSTI2014

MATCHED-INDEX-OF-REFRACTION FLOW FACILITY FOR FUNDAMENTAL AND APPLIED RESEARCH

Significant challenges face reactor designers with regard to thermal hydraulic design and associated modeling for advanced reactor concepts. Computational thermal hydraulic codes solve only a piece of the core. There is a need for a whole core dynamics system code with local resolution to investigate and understand flow behavior with all the relevant physics and thermo-mechanics. The matched index of refraction (MIR) flow facility at Idaho National Laboratory (INL) has a unique capability to contribute to the development of validated computational fluid dynamics (CFD) codes through the use of state-of-the-art optical measurement techniques, such as Laser Doppler Velocimetry (LDV) and Particle Image Velocimetry (PIV). PIV is a non-intrusive velocity measurement technique that tracks flow by imaging the movement of small tracer particles within a fluid. At the heart of a PIV calculation is the cross correlation algorithm, which is used to estimate the displacement of particles in some small part of the image over the time span between two images. Generally, the displacement is indicated by the location of the largest peak. To quantify these measurements accurately, sophisticated processing algorithms correlate the locations of particles within the image to estimate the velocity (Ref. 1). Prior to use with reactor deign, the CFD codes have to be experimentally validated, which requires rigorous experimental measurements to produce high quality, multi-dimensional flow field data with error quantification methodologies. Computational thermal hydraulic codes solve only a piece of the core. There is a need for a whole core dynamics system code with local resolution to investigate and understand flow behavior with all the relevant physics and thermo-mechanics. Computational techniques with supporting test data may be needed to address the heat transfer from the fuel to the coolant during the transition from turbulent to laminar flow, including the possibility of an early laminarization of the flow (Refs. 2 and 3) (laminarization is caused when the coolant velocity is theoretically in the turbulent regime, but the heat transfer properties are indicative of the coolant velocity being in the laminar regime). Such studies are complicated enough that computational fluid dynamics (CFD) models may not converge to the same conclusion. Thus, experimentally scaled thermal hydraulic data with uncertainties should be developed to support modeling and simulation for verification and validation activities. The fluid/solid index of refraction matching technique allows optical access in and around geometries that would otherwise be impossible while the large test section of the INL system provides better spatial and temporal resolution than comparable facilities. Benchmark data for assessing computational fluid dynamics can be acquired for external flows, internal flows, and coupled internal/external flows for better understanding of physical phenomena of interest. The core objective of this study is to describe MIR and its capabilities, and mention current development areas for uncertainty quantification, mainly the uncertainty surface method and cross-correlation method. Using these methods, it is anticipated to establish a suitable approach to quantify PIV uncertainty for experiments performed in the MIR.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2012

Development of In-Can Melting Process Applied to Vitrification of High Activity Waste Solutions (HAWS): Glass characterizations and process tests results - 12442

The CEA has selected vitrification for specific High-Activity nuclear Waste Solutions (HAWS) containing large quantities of salts. This choice has led the CEA Marcoule to develop a compact 'in-can' batch melting process in which the melting pot is disposable and serves as the primary canister for the solidified glass. This process is particularly suitable for the treatment of small waste quantities (less than 10 m{sup 3} per year) and low flow rates (5 to 10 L/h) which do not justify the use of a Cold Crucible Induction Melter. The unit capacity is approximately one hundred kilograms of glass a week operating alternately between feeding during the day and surveillance at night. In order to be fully representative of the glove box to be implemented, a new nonradioactive pilot-scale unit in which the core process (furnace and dust scrubber) is completely enclosed with glove box simulation was built at CEA Marcoule in 2008. The equipment includes all the systems and components necessary to perform full-scale tests: feed system, furnace and complete off-gas treatment system. The nominal tests were performed in 2009 and 2010 to verify that no problems arose in vitrifying solutions under the specified conditions. Two different liquid feeds representatives of the current HAWS stored and future solutions were used. The transient runs were carried out in this facility in 2010. Their objectives were to validate the glass product with different operating conditions and to determine optimum parameters for transient phases such as decreased volatility during standby phases. Finally, all the material obtained under nominal conditions or different operating conditions (e.g. initial glass frit quantity, standby temperature or restart procedure of feeding after night surveillance) have been characterized and described. The impact of transient phases on the process is then discussed in terms of volatility, thermal balance, etc., and compared with nominal tests results. Off-gas treatment system (OGTS) assessments determined preliminary decontamination factors for the OGTS components and allowed comparison between the two types of solutions and for different operating parameters. Since 2005 CEA Marcoule has been developing an 'in-can melting' vitrification process for specific High Activity Nuclear Waste Solutions. The tests carried out to date have validated the feasibility of this process and confirmed the direct vitrification option in which the liquid and solid feed streams are supplied directly to a disposable melting pot. CEA Marcoule began process qualification testing in 2009 in a new facility using equipment representative of the devices that will be installed in a glove box. The nominal mode tests performed in 2009 and 2010 were used to determine nominal operating conditions for the process: - a nominal process temperature of 1100 deg. C; - a maximum glass production rate of 5 kg/h; - a liquid feed solution flow rate of 5 L/h or less if the glass production rate exceeds the preceding maximum value; - a liquid recycle rate of 0.5 L/h for a nominal solution feed rate 5 L/h. They also produced glass samples generally meeting our expectations, and allowed us to measure the characteristic properties (viscosity, density, thermal conductivity, chemical durability). The first test of transient operation in 2010 yielded glass consistent with expectations and showed that reducing the temperature had no significant effect on the volatility of the constituent elements. However, a significant impact on the release of elements at the beginning of the test was observed with a larger initial quantity of glass frit on startup. The process qualification program will now continue with tests of degraded operating modes. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

3-D Gamma-ray Mapping from Unmanned Aerial Systems for Nuclear Decommissioning - 18439

Advanced gamma-ray detection technologies integrated with sophisticated robotic platforms will enable safer and more cost and time-efficient capabilities in support of nuclear decommissioning, waste management, and environmental remediation activities within the United States Department of Energy (U.S. DOE) complex and in the global nuclear power industry. In the Applied Nuclear Physics program at Lawrence Berkeley National Laboratory, we have developed the Nuclear Scene Data Fusion (SDF) capability to map gamma-ray emitting sources in large-scale, 3-D environments in real-time. This powerful capability has been successfully deployed in real-world environments, from a test-bed in Berkeley, CA to the exclusion zone in Fukushima Prefecture, Japan to support environmental remediation and contamination mapping efforts within evacuated communities, and is also currently being further developed in support of decommissioning efforts at the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) in collaboration with the Japan Atomic Energy Agency (JAEA). In this work, we will provide an overview of SDF adapted for gamma-ray mapping onboard an UAS, as well as results from measurements demonstrating point and distributed source mapping. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Reconceptualizing public participation in environmental assessment as EA civics

Notwithstanding the considerable attention placed on creating meaningful opportunities for public participation in environmental assessment (EA), many participants and those who have reviewed participation processes often find practice sorely wanting. This reality stands in stark juxtaposition to future environmental governance needs, which will require increased openness, deliberation and transdisciplinary knowledge in order to deal with environmental change that is ever more uncertain, complex and conflictual. In this paper, our purpose was to consider how to meet those needs through reconceptualizing public participation as EA civics, founded on an active citizen base, deliberative in nature and orientated toward learning. We do this through developing a new conceptual model of next generation participation processes that is relevant at multiple spatial scales and institutional levels, is applicable to the entire assessment cycle and spans temporal scales through feedback loops. Our EA civics model builds on the “civics approach” to environmental governance and “action civics” by extending their core ideas to participation in EA. We did this by conducting an integrative literature review (including numerous papers we have contributed over the years) and reflecting on our own experiences as EA participants. We apply current thinking on public participation design to our EA civics conceptualization and highlight important design features that have received scant attention. We conclude that EA civics holds promise for fairer and more robust participation processes if all aspects of the model are considered and the actions related to each are implemented. - Highlights: • Consideration of the ‘civics approach’ and ‘action civics’ in an EA context • Conceptualization of public participation as EA civics • Reflection on the EA civics as a model of participation suitable for next generation assessment.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2025

Solid State Transformer Architecture and Control Compensation for Common Mode Currents

A high-altitude electromagnetic pulse (HEMP) or similar geomagnetic disturbance (GMD) has the potential to impact the operation of large-scale electric power grids. By introducing low-frequency common-mode (CM) currents, these events can degrade the performance of critical system components, such as large power transformers by introducing CM currents which can lead to magnetic saturation of the transformer core. In this work, a solid-state transformer (SST) is developed to replace susceptible equipment and improve grid resiliency by safely absorbing these CM disturbances. This device will be referred to as a common-mode solid-state transformer (CM-SST). An SST architecture based on a four-legged AC/DC converter is developed. This architecture enables active control of CM signals without disturbing the AC voltages or the real and reactive power delivery capabilities. A system-level model of this architecture is created, and time-domain simulations are performed to evaluate the SST’s performance in response to simulated CM disturbances. A control strategy for mitigating CM current is also investigated. Hamiltonian surface shaping and power flow control (HSSPFC) is used to design a nonlinear controller for the SST’s output inverter. The objectives of the controller are to suppress CM-induced AC current offsets and regulate AC currents to desired setpoints. Nonlinear system analysis is applied to design and validate the controller. Two cases are tested: (a) the proposed four-leg inverter and (b) a standard three-leg inverter. The results show that the proposed controller rapidly mitigates CM disturbances while maintaining high-quality AC current waveforms in the four-leg configuration. Finally, the hardware performance of an SST prototype is evaluated. In particular, the ability of the SST to safely redirect and absorb CM currents is demonstrated, showing how it can protect neighboring conventional transformers in the system. The study confirms that appropriate control laws allow the SST to protect both itself and adjacent transformers during a HEMP or GMD event.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2011

Secondary Waste Form Down-Selection Data Package—DuraLith

This data package developed for the DuraLith wasteform includes information available in the open literature and from data obtained from testing currently underway. DuraLith is an alkali-activated geopolymer waste form developed by the Vitreous State Laboratory at The Catholic University of America (VSL-CUA) for encapsulating liquid radioactive waste. A DuraLith waste form developed for treating Hanford secondary waste liquids is prepared by alkali-activation of a mixture of ground blast furnace slag and metakaolinite with sand used as a filler material. Based on optimization tests, solid waste loading of {approx}7.5% and {approx}14.7 % has been achieved using the Hanford secondary waste S1 and S4 simulants, respectively. The Na loading in both cases is equivalent to {approx}6 M. Some of the critical parameters for the DuraLith process include, hydrogen generation and heat evolution during activator solution preparation using the waste simulant, heat evolution during and after mixing the activator solution with the dry ingredients, and a working window of {approx}20 minutes to complete the pouring of the DuraLith mixture into molds. Results of the most recent testing indicated that the working window can be extended to {approx}30 minutes if 75 wt% of the binder components, namely, blast furnace slag and metakaolin are replaced by Class F fly ash. A preliminary DuraLith process flow sheet developed by VSL-CUA for processing Hanford secondary waste indicated that 10 to 22 waste monoliths (each 48 ft3 in volume) can be produced per day. There are no current pilot-scale or full-scale DuraLith plants under construction or in operation; therefore, the cost of DuraLith production is unknown. The results of the non-regulatory leach tests, EPA Draft 1313 and 1316, Waste Simulant S1-optimized DuraLith specimens indicated that the concentrations of RCRA metals (Ag, Cd, Cr, Hg, and Pb) in the leachates were well below the Universal Treatment Standard limits in 40 CFR 268.48. The data from the EPA draft 1315 leach test showed that LI values for COCs, namely 99Tc and I, ranged from 8.2 to 11.4 and 4.3 to 7.5, respectively. These values indicate that 99Tc meets the WAC LI requirement of 9.0 whereas, the LI values for I does not meet the WAC requirement of 11.0. Results of Toxicity Characteristic Leaching Procedure (TCLP)(EPA Method 1311) conducted on Waste Simulant S1-optimized DuraLith specimens, indicated that the concentrations of RCRA metals (Ag, As, Cd, Cr, Hg, and Pb) in the leachates were well below the Universal Treatment Standard limits in 40 CFR 268.48. The data from the ANSI/ANS 16.1 leach test showed that LI values for COC, namely Re (as a Tc surrogate), ranged from 8.06 to 10.81. The LI value for another COC, namely I, was not measured in this test. The results of the compressive strength testing of Waste Simulant S1-optimized DuraLith specimens indicated that the monoliths were physically robust with compressive strengths ranging from 115.5 MPa (16757 psi) to 156.2 MPA (22667 psi).

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

Progress of full-scale MCNP6{sup TM} model development of NuScale small modular reactor - 25394

This paper presents the recent progress of development of full-scale MCNP6{sup TM} small modular reactor within NuScale Power LLC (NuScale) using MCNP6{sup TM} version 1.0. This model currently is being used to determine of vessel neutron fluence, nuclear damage, and radiological consequence analysis. The results of the best estimate fluence analysis to support Design Certification Application (DCA) and technical details has been included within License Technical Report (LTR) which had been submitted to US NRC for review in 2017. Currently the detailed analysis of using this full-scale NuScale SMR model is focusing on operational radiological external dose exposure, nuclear damage, nuclear heating and neutron activation of SMR components to support optimized design and RAI (request additional information) response activities. (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2016

Results from the DarkSide-50 Dark Matter Experiment

While there is tremendous astrophysical and cosmological evidence for dark matter, its precise nature is one of the most significant open questions in modern physics. Weakly interacting massive particles (WIMPs) are a particularly compelling class of dark matter candidates with masses of the order 100 GeV and couplings to ordinary matter at the weak scale. Direct detection experiments are aiming to observe the low energy (<100 keV) scattering of dark matter off normal matter. With the liquid noble technology leading the way in WIMP sensitivity, no conclusive signals have been observed yet. The DarkSide experiment is looking for WIMP dark matter using a liquid argon target in a dual-phase time projection chamber located deep underground at Gran Sasso National Laboratory (LNGS) in Italy. Currently filled with argon obtained from underground sources, which is greatly reduced in radioactive 39Ar, DarkSide-50 recently made the most sensitive measurement of the 39Ar activity in underground argon and used it to set the strongest WIMP dark matter limit using liquid argon to date. This work describes the full chain of analysis used to produce the recent dark matter limit, from reconstruction of raw data to evaluation of the final exclusion curve. The DarkSide- 50 apparatus is described in detail, followed by discussion of the low level reconstruction algorithms. The algorithms are then used to arrive at three broad analysis results: The electroluminescence signals in DarkSide-50 are used to perform a precision measurement of ii longitudinal electron diffusion in liquid argon. A search is performed on the underground argon data to identify the delayed coincidence signature of 85Kr decays to the 85mRb state, a crucial ingredient in the measurement of the 39Ar activity in the underground argon. Finally, a full description of the WIMP search is given, including development of cuts, efficiencies, energy scale, and exclusion curve in the WIMP mass vs. spin-independent WIMP-nucleon scattering cross section plane. This work was supervised by Hanguo Wang and was completed in collaboration with members of the DarkSide collaboration.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2012

Beyond the buildingcentric approach: A vision for an integrated evaluation of sustainable buildings

The available sustainable building evaluation systems have produced a new environmental design paradigm. However, there is an increasing need to overcome the buildingcentric approach of these systems, in order to further exploit their innovate potential for sustainable building practices. The paper takes this challenge by developing a cross-scale evaluation approach focusing on the reliability of sustainable building design solutions for the context in which the building is situated. An integrated building-urban evaluation model is proposed based on the urban matrix, which is a conceptualisation of the built environment as a social-ecological system. The model aims at evaluating the sustainability of a building considering it as an active entity contributing to the resilience of the urban matrix. Few holistic performance indicators are used for evaluating such contribution, so expressing the building reliability. The discussion on the efficacy of the model shows that it works as a heuristic tool, supporting the acquisition of a better insight into the complexity which characterises the relationships between the building and the built environment sustainability. Shading new lights on the meaning of sustainable buildings, the model can play a positive role in innovating sustainable building design practices, thus complementing current evaluation systems. - Highlights: Black-Right-Pointing-Pointer We model an integrated building-urban evaluation approach. Black-Right-Pointing-Pointer The urban matrix represents the social-ecological functioning of the urban context. Black-Right-Pointing-Pointer We introduce the concept of reliability to evaluate sustainable buildings. Black-Right-Pointing-Pointer Holistic indicators express the building reliability. Black-Right-Pointing-Pointer The evaluation model works as heuristic tool and complements other tools.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2011

Glass Formulation for Next Generation Cold Crucible Induction Melter

Transformational melter technologies are being considered to support mission acceleration within the U.S. Department of Energy (DOE) complex. New glass formulations are required to take full advantage of the next generation melters, for example, the cold crucible induction melter (CCIM). The key advantage of CCIM technology over current reference technologies is its capability to provide higher processing temperatures, which can lead to an increased waste throughput rate by achieving higher waste loadings and by increasing the feed processing rate. Various waste compositions within the DOE complex were evaluated to determine their potential for successfully demonstrating the unique advantages of the CCIM technology. Glass formulations that satisfy a set of constraints for product quality and assumed CCIM processing conditions were developed for two Hanford waste streams, AZ-101 high-level waste (HLW) and AN-105 low-activity waste (LAW). Three glasses selected for AZ-101 HLW have waste loadings of 40, 42.5, and 45 wt%. The 45-wt% waste loading corresponds to a 22% increase from 37 wt%, which is the maximum expected waste loading based on the current reference formulation. One glass selected for AN-105 LAW has a waste loading of 31.3 wt% at 24 wt% Na2O in glass, which is a 14% increase from the current reference formulation maximum of 21 wt% Na2O. These four glasses are planned for scaled melter tests for initial demonstration of the CCIM technologies for Hanford wastes.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2022

In-Cell Thermal Creep Frame Capability: Out-of-Cell Construction and Subsized Sample Testing

This report describes the activities related to the construction of an in-cell thermal creep test facility for small-scale specimens in the irradiation-assisted stress-corrosion cracking (IASCC) hotcell located at the Fuels and Applied Science Building (FASB) at INL. The whole project includes three stages: (i) conceptual design; (ii) out-of-cell demonstration tests; and (iii) in-cell demonstration testing. During the current fiscal year (FY)-2022, materials and equipment required to construct the conceptual design outlined in a previous report were procured. Frames for conducting out-of-cell testing have been constructed, and testing plans have been developed to assess the operation of the newly constructed frames. Preliminary testing of flat subsized tensile specimens on ASTM creep frames has also been completed for two sample thicknesses: 0.75 mm and 1.0 mm.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Multi-scale models of whole cells: progress and challenges

Whole-cell modeling is “the ultimate goal” of computational systems biology and “a grand challenge for 21st century”. These complex, highly detailed models account for the activity of every molecule in a cell and serve as comprehensive knowledgebases for the modeled system. Their scope and utility far surpass those of other systems models. In fact, whole-cell models (WCMs) are an amalgam of several types of “system” models. The models are simulated using a hybrid modeling method where the appropriate mathematical methods for each biological process are used to simulate their behavior. Given the complexity of the models, the process of developing and curating these models is labor-intensive and to date only a handful of these models have been developed. While whole-cell models provide valuable and novel biological insights, and to date have identified some novel biological phenomena, their most important contribution has been to highlight the discrepancy between available data and observations that are used for the parametrization and validation of complex biological models. Another realization has been that current whole-cell modeling simulators are slow and to run models that mimic more complex (e.g., multi-cellular) biosystems, those need to be executed in an accelerated fashion on high-performance computing platforms. In this manuscript, we review the progress of whole-cell modeling to date and discuss some of the ways that they can be improved.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2021

Achieving industrial ammonia synthesis rates at near-ambient conditions through modified scaling relations on a confined dual site

The production of ammonia through the Haber–Bosch process is regarded as one of the most important inventions of the 20th century. Despite significant efforts in optimizing the process, it still consumes 1 to 2% of the worldwide annual energy for the high working temperatures and pressures. The design of a catalyst with a high activity at milder conditions represents another challenge for this reaction. Herein, we combine density functional theory and microkinetic modeling to illustrate a strategy to facilitate low-temperature and -pressure ammonia synthesis through modified energy-scaling relationships using a confined dual site. Our results suggest that an ammonia synthesis rate two to three orders of magnitude higher than the commercial Ru catalyst can be achieved under the same reaction conditions with the introduction of confinement. Such strategies will open pathways for the development of catalysts for the Haber–Bosch process that can operate at milder conditions and present more economically viable alternatives to current industrial solutions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2013

Low Cost Electrochromic Film on Plastic for Net-Zero Energy Buildings

Over 4 Quads of energy are lost through windows annually. Passive coatings reduce wasted energy, but energy lost through windows would remain over 2 Quads with complete replacement of Low-E glass. Active control of transmitted light and solar heating with electrochromic (EC) windows can transform the efficiency of energy use within buildings, thereby reducing energy footprints and corresponding greenhouse emissions. High production, integration, and distribution cost limits adoption of current EC products. ITN aimed to utilize its proven heritage of efficiently transitioning technologies from rigid to flexible substrates employing roll-to-roll manufacturing to capture the emerging EC window market opportunity. The project focused on three main efforts (1) Transition Small Scale Prototypes To Limited 0.5 Meter Wide, Web Coater Production, (2) Satisfy Market Driven EC Performance Metrics on Plastic Substrates, and (3) Product Development and Commercialization. The overall goal was to substantially reduce investor risk to motivate private investment in a production facility to further transition and scale this promising technology. A 0.5 meter roll-to-roll web coater was designed, constructed, and commissioned at ITN to support EC development effort. With this tool, we were able to establish the feasibility of roll-to-roll production of EC devices. Individually layers were continuously produced at lengths up to 3 meters with good uniformity, both down web and cross web. Solid state devices were produced, and device performance was being enhanced through hardware modifications underway at the close of the project. When deployed in composite device structures, we were able to verify that individual layers were able to achieve a transmission range of 3-70% transmission average over the visible portion of the spectrum. Initial development of intelligent process controls led to verification of a 2-state controller employed during deposition of the electrochromic layer. The project also successfully increased device performance in line with market needs. Improved device materials provided increased transmission range to a 5-65% transmission over the visible spectrum and faster switching times for both small area batch parts and large area composite materials. We were able to demonstrate durable cycling over 10,000-20,000 cycles in a variety of architectures including suspended films in an IGU and films laminated to glass tested in open air representative of retrofit applications. Robust packaging techniques were identified and samples proved durable even in 40C and 100% relative humidity outside the IGU environment.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2019

Development of Irradiation Test Devices for Transient Testing

The Transient Reactor Test facility (TREAT) resumed operations in 2017 in order to reclaim its crucial role in nuclear-heated fuel safety research. TREAT’s historic era of operation (1959-1994) was best known for integral-scale testing of large fuel specimens/bundles under postulated reactor plant accident conditions, but TREAT also supported smaller-scale phenomena identification tests that elucidated fundamental behaviors and paved the way for these integral-scale tests. Advances in modern computational capabilities and a resurgence of interest in novel reactor technologies have created an opportunity for emphasizing modernized science-based and separate effects tests once again at TREAT. An innovative approach to this type of testing has been developed to leverage minor radioactivity built-in during brief TREAT irradiations by arranging smaller fuel specimens in low activation hardware so that they can be easily extracted and shipped for post irradiation examination within weeks. This recently-established capability, termed the Minimal Activation Retrievable Capsule Holder (MARCH) irradiation vehicle system, includes capabilities for cost-effective simplified-environment testing of centimeter-scale fuel samples of various geometries, temperature-controlled irradiations of millimeter-size samples for lower-length-scale model development, liquid-metal bonded heat sink capsules for controlling transient temperature response in fuel rodlets, and an innovative approach to high throughput irradiation of transient sensors and instrumentation. The MARCH system’s capabilities will also set the foundation for fuel safety research performed in larger integral-scale test devices with coolant environments representing reactor plants. Based upon historic approaches, but modernized to meet current nuclear technology needs, these larger irradiation devices include flowing pressurized water (including the ability to depressurize to steam) as well liquid metal cooling loops for various fuel rod and small bundle specimens. Here, this paper describes the recently-established MARCH system and current trajectory to enabling advanced transient science with a suite of irradiation test devices.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗