Results for “time evolution operators” — Page 46

DOE OSTI2016

NUHOMS{sup R} EOS (Extended Optimized Storage): Robust, Advanced, and Dual Purpose Dry Storage System - 16472

AREVA TN has completed the design, analysis, and US NRC license submittal for the NUHOMS{sup R} Extended Optimized Storage (EOS) system. NUHOMS{sup R} EOS offers a large capacity and high heat load dry storage and transportation solution for UNF. EOS is not a new system, but an evolution of the already-proven safe and low-risk horizontal NUHOMS{sup R} storage system, which is one of the most widely used UNF dry storage systems in the United States. The EOS system features a 37PTH dry shielded canister (DSC) for 37 PWR UNF assemblies and an 89BTH DSC for the 89 BWR UNF assemblies. The EOS DSCs will be stored inside a horizontal storage module (HSM) that is a robust, fortress-like concrete storage overpack. Designed with the lessons learned from the Fukushima event in Japan in mind, EOS has robust margins for beyond design basis (BDB) events and offers the lowest risk and highest safety margin of any dry storage system design for recovery from BDB events. EOS also offers innovative aging management features with an aging management program (AMP) to assure safe and low dose long-term storage at the utility sites. EOS incorporates ports for AMP inspections and offers the option of using duplex stainless steel (DSS) for the DSC shell in order to negate corrosion issues. EOS is stored horizontally and above ground, making it easy and quick to access for visual inspection, monitoring, and mitigating actions during AMP. NUHOMS{sup R} EOS is optimized for high capacity, high burnup, high enrichments, and very low cooling times for UNF assemblies. It enables the highest heat load per canister (50 kW) and low dose rates. Even with high heat loads, EOS has significant margins to design basis limits. As the future of used fuel disposition will require the need to move fuel off-site to interim or consolidated storage, EOS is the ideal solution as it enables on-site loading and unloading operations that mitigate risk when transferring fuel on-site or transporting fuel off-site. The EOS design can be safely located in a traditional outdoor setting with fortress-like concrete reinforced modules that offer superior resistance to attack or can be safely operated inside of a building enclosure for those utilities desiring a more discreet siting for its used fuel storage systems. EOS has an innovative basket design that is made of high strength low alloy (HSLA) material and is easy to fabricate due to its non-welded design. Its innovative inlet and outlet air vent design, which incorporates dose reduction hardware, allows for optimal ambient airflow for highly efficient heat transfer with minimal radiation dose. The NUHOMS{sup R} EOS storage modules are interlocked in a side-by-side configuration offering superior and robust seismic performance. The license application for NUHOMS{sup R} EOS is currently under US NRC review and this system will be available for deployment in 2017. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2018

Handling and Treatment of Sodium-Potassium Alloy (NaK) after the Loss of Key Personnel – 19002

ABSTRACT In September 2010, during cleanup and removal efforts associated with a glovebox containing a sodium-potassium alloy (NaK) cooling system, a NaK reaction event occurred. Near the end of the evolution, which was at a Materials and Fuels Complex (MFC) research facility at the Idaho National Laboratory, a 2 to 3-ounce sample of NaK was being transferred from a metal can to a polyethylene bottle so it could be sent to the disposal outlet for verification analysis. During the transfer, a reaction of the NaK with ambient air was observed in both the metal can and sample container. The potential for a reaction was identified during the planning of this activity and mitigating steps were included in the procedures. In response, the two containers were flooded with argon, closed, and observed overnight. No additional reaction was noted. The sample container and metal can were packaged into a 10-gallon drum and transferred to a permitted storage location pending disposal. While the other containers generated from the deactivation and decommissioning activity were sent off-site for disposal, the 10-gal drum remained due to concerns by a staff specialist that the material could contain potassium superoxide (KO2) as a result of the reaction event. The intent at that time was to treat the NaK in a Resource Conservation and Recovery Act (RCRA)-permitted treatment facility at MFC, instead of sending it off-site for disposal. The container was labeled, inspected, and managed as a hazardous waste. Due to the complexities associated with safely handling and treating NaK and KO2, the container remained in storage. Treatment and disposal of the NaK and KO2 container was revisited in 2016, when researchers and chemists were consulted regarding the potential for superoxide formation and the best means to safely store and treat the container. The facility came to realize that due to the retirements of key personnel, it needed to provide current employees operational experience with the handling and treatment of NaK. An outside company was identified and contracted to provide training and consulting services. Several Battelle Energy Alliance, Inc. (BEA) personnel then attended an alkali metals safety training class. The training course provided participants with classroom and hands–on instruction associated with: • Hazards associated with handling and using sodium and NaK • Proper personal protection equipment, spill control techniques, and first aid • Common design approaches for buildings, systems, and equipment used to contain sodium and NaK • What to expect in the event of a water reaction and how to respond • How to properly prepare for a fire and contain/extinguish small metal fires • A hands-on demonstration of NaK reaction and controls. Following the training, a procedure was developed to open the container, and inspect and treat the NaK. In June 2017, facility operations personnel successfully completed the inspection and treatment of the NaK drum, eliminating the legacy liability.

99 GENERAL AND MISCELLANEOUS↗

DOE OSTI2020

Implications of End Points on Remediation - 20476

The Port Hope Area Initiative (PHAI) is a federal environmental clean-up program. Its mandate is the remediation and local, long-term, safe management of approximately 1.7 million cubic metres of historic low-level radioactive waste in the adjacent communities of Port Hope and Port Granby in Southern Ontario, Canada. The PHAI is being undertaken by Canadian Nuclear Laboratories (CNL), on behalf of Atomic Energy of Canada Limited, a federal Crown corporation. It is currently one of the largest environmental remediation projects in Canada. The safety of workers, the public and the environment while delivering the PHAI compliantly, on time and within budget is CNL's number one priority. The PHAI is being implemented as two projects - the Port Hope Project and the Port Granby Project. The Port Hope Project is the larger of the two and includes the cleanup of approximately 1.2 million cubic metres of historic waste. The Port Hope Project includes a unique and important component - the remediation of approximately 1,200 private residences and businesses to include both interior and exterior verification of soil and surface-contaminated objects. Planning and consultation for the PHAI clean-up criteria and remediation verification standard operating procedures (RVSOP) were initiated in the early 2000's. The criteria were developed through a cooperative effort involving the PHAI, scientific specialists, federal and provincial government agencies, peer reviewers, the municipalities and members of the public. Subsequent verification procedures which detail the unique systematic methods to verify compliance with the clean-up criteria were developed by CNL in consultation with federal regulators and relevant stakeholders. Now, specifically with the Port Hope Small-Scale Sites project having been underway for a year and approximately 38 properties in some stage of remediation, it has become increasingly evident that the practical application of the clean-up criteria and RVSOP methodology is posing unique challenges that are having direct impact on project execution. The current RVSOP approach is based on discrete sample verification not allowing failure of any one sample. When implemented in the field, particularly at the Small-Scale Sites, it leads to a much more extensive excavation than what was accounted for in the original design, the implications of which are substantial delays in project progress and much more significant impact on the individual properties than originally anticipated. This paper will examine the evolution of PHAI clean-up criteria, subsequent RVSOP methodology and its impact on current project execution and the justification for exploring potential revisions to methods of remediation verification. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2018

Replacement of Melter 2 at the Defense Waste Processing Facility (DWPF) - 18608

The original DWPF melter was replaced in 2002 with an identical unit, and radioactive operation of Melter 2 commenced in 2003. After nearly 14 years of service, a lower electrode failure of Melter 2 occurred in February 2017 which required its removal and replacement with Melter 3. The scope of the replacement outage involves several significant evolutions: - Shutdown of Melter 2 and placement into a safe state; - Remote external and internal inspection of Melter 2 to chronicle its condition prior to removal; - Disassembly and removal of Melter 2 from the process cell; - Placement of Melter 2 into a storage box and transport to a storage vault; - Preparation and initial testing of Melter 3 prior to transport to the DWPF; - Transport to the DWPF and installation of Melter 3 in the process cell; - Final startup testing and initiation of radioactive operation. Upon determination that repair of Melter 2 was not feasible, DWPF created an outage team to integrate schedules and resources needed to execute melter replacement as well as including maintenance scope for facility work that can only be performed when the melter is de-energized. The execution of this scope required integration with other mission critical outage activities already in progress, and planned to start, including initial facility tie-in scope for the new Salt Waste Processing Facility (SWPF). This unplanned addition of the melter replacement scope to the existing outage scope resulted in the longest facility outage period since the initiation of radioactive operations at the DWPF in 1996. Successful completion of this scope across all Liquid Waste facilities would require balance - for schedules, resources, priority, funding, etc. To overcome the significant challenges created by this additional scope, a WAR Room was established to ensure adequate integration and coordination of critical resources, and daily progress. The execution of this scope has required the integration of nearly two dozen work groups across multiple facilities at Savannah River Site (SRS), in addition to support from nearly a dozen vendors. The melter replacement outage was executed with a high degree of disciplined operation to ensure the facility was ready to resume glass pouring operation in time to support restart of the Liquid Waste program at the Savannah River Site (SRS). This paper will provide a brief overview of Melter 2 operational history. The execution of the removal and replacement operations will be described with a specific focus on lessons learned and opportunities where the outage execution diverged from the original Melter 1 replacement outage. It is expected to be of interest to vitrification facilities, as well as facilities, which require remote maintenance and replacement of large process equipment. (author)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2019

Handling and Treatment of Sodium-Potassium Alloy (NaK) after the Loss of Key Personnel - 19002

In September 2010, during cleanup and removal efforts associated with a glovebox containing a sodium-potassium alloy (NaK) cooling system, a NaK reaction event occurred. Near the end of the evolution, which was at a Materials and Fuels Complex (MFC) research facility at the Idaho National Laboratory, a 2 to 3-ounce sample of NaK was being transferred from a metal can to a polyethylene bottle so it could be sent to the disposal outlet for verification analysis. During the transfer, a reaction of the NaK with ambient air was observed in both the metal can and sample container. The potential for a reaction was identified during the planning of this activity and mitigating steps were included in the procedures. In response, the two containers were flooded with argon, closed, and observed overnight. No additional reaction was noted. The sample container and metal can were packaged into a 10-gallon drum and transferred to a permitted storage location pending disposal. While the other containers generated from the deactivation and decommissioning activity were sent off-site for disposal, the 10-gal drum remained due to concerns by a staff specialist that the material could contain potassium superoxide (KO{sub 2}) as a result of the reaction event. The intent at that time was to treat the NaK in a Resource Conservation and Recovery Act (RCRA)-permitted treatment facility at MFC, instead of sending it off-site for disposal. The container was labeled, inspected, and managed as a hazardous waste. Due to the complexities associated with safely handling and treating NaK and KO{sub 2}, the container remained in storage. Treatment and disposal of the NaK and KO{sub 2} container was revisited in 2016, when researchers and chemists were consulted regarding the potential for superoxide formation and the best means to safely store and treat the container. The facility came to realize that due to the retirements of key personnel, it needed to provide current employees operational experience with the handling and treatment of NaK. An outside company was identified and contracted to provide training and consulting services. Several Battelle Energy Alliance, Inc. (BEA) personnel then attended an alkali metals safety training class. The training course provided participants with classroom and hands-on instruction associated with: - Hazards associated with handling and using sodium and NaK; - Proper personal protection equipment, spill control techniques, and first aid; - Common design approaches for buildings, systems, and equipment used to contain sodium and NaK; - What to expect in the event of a water reaction and how to respond; - How to properly prepare for a fire and contain/extinguish small metal fires; - A hands-on demonstration of NaK reaction and controls. Following the training, a procedure was developed to open the container, and inspect and treat the NaK. In June 2017, facility operations personnel successfully completed the inspection and treatment of the NaK drum, eliminating the legacy liability. (authors)

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2016

WE-DE-207A-01: Parallels in the Evolution of X-Ray Angiographic Systems and Devices Used for Minimally Invasive Endovascular Therapy

1. Parallels in the evolution of x-ray angiographic systems and devices used for minimally invasive endovascular therapy Charles Strother - DSA, invented by Dr. Charles Mistretta at UW-Madison, was the technology which enabled the development of minimally invasive endovascular procedures. As DSA became widely available and the potential benefits for accessing the cerebral vasculature from an endovascular approach began to be apparent, industry began efforts to develop tools for use in these procedures. Along with development of catheters, embolic materials, pushable coils and the GDC coils there was simultaneous development and improvement of 2D DSA image quality and the introduction of 3D DSA. Together, these advances resulted in an enormous expansion in the scope and numbers of minimally invasive endovascular procedures. The introduction of flat detectors for c-arm angiographic systems in 2002 provided the possibility of the angiographic suite becoming not just a location for vascular imaging where physiological assessments might also be performed. Over the last decade algorithmic and hardware advances have been sufficient to now realize this potential in clinical practice. The selection of patients for endovascular treatments is enhanced by this dual capability. Along with these advances has been a steady reduction in the radiation exposure required so that today, vascular and soft tissue images may be obtained with equal or in many cases less radiation exposure than is the case for comparable images obtained with multi-detector CT. Learning Objectives: To understand the full capabilities of today’s angiographic suite To understand how c-arm cone beam CT soft tissue imaging can be used for assessments of devices, blood flow and perfusion. Advances in real-time x-ray neuro-endovascular image guidance Stephen Rudin - Reacting to the demands on real-time image guidance for ever finer neurovascular interventions, great improvements in imaging chains are being pursued. For the highest spatial and temporal resolution, x-ray guidance with fluoroscopy and angiography although dominant are still being vastly improved. New detectors such as the Micro-Angiographic Fluoroscope (MAF) and x-ray source designs that enable higher outputs while maintaining small focal spots will be highlighted along with new methods for minimizing the radiation dose to patients. Additionally, new platforms for training and device testing that include patient-specific 3D printed vascular phantoms and new metrics such as generalized relative object detectability for objectively inter-comparing systems will be discussed. This will improve the opportunity for better evaluation of these technological advances which should contribute to the safety and efficacy of image guided minimally invasive neuro-endovascular procedures. Learning Objectives: To understand the operation of new x-ray imaging chain components such as detectors and sources To be informed about the latest testing methods, with 3D printed vascular phantoms, and new evaluation metrics for advanced imaging in x-ray image guided neurovascular interventions Advances in cone beam CT anatomical and functional imaging in angio-suite to enable one-stop-shop stroke imaging workflow Guang-Hong Chen - The introduction of flat-panel detector based cone-beam CT in clinical angiographic imaging systems enabled treating physicians to obtain three-dimensional anatomic roadmaps for bony structure, soft brain tissue, and vasculatures for treatment planning and efficacy checking after the procedures. However, much improvement is needed to reduce image artifacts, reduce radiation dose, and add potential functional imaging capability to provide four-dimensional dynamic information of vasculature and brain perfusion. In this presentation, some of the new techniques developed to address radiation dose issues, image artifact reduction and brain perfusion using C-arm cone-beam CT imaging system will be introduced for the audience. Learning Objectives: To understand the clinical need of one-stop-shop stroke imaging workflow To understand to technical challenges in cone beam CT perfusion To understand the potential technical solutions to enable one-stop-shop imaging workflow Recent advances in devices used in neuro--interventions Mattew Gounis - Over the past two decades, there has been explosive development of medical devices that have revolutionized the endovascular treatment of cerebrovascular diseases. There is now Level 1, Class A evidence that intra-arterial, mechanical thrombectomy in acute ischemic stroke is superior to medical management; and similarly that minimally invasive, endovascular repair of ruptured brain aneurysms is superior to surgical treatment. Stent-retrievers are now standard of care for emergent large vessel occlusions causing a stroke, with a number of patients need to treat for good clinical outcomes as low as 4. Recent technologies such as flow diverters and disrupters, intracranial self-expanding stents, flexible large bore catheters that can reach vessels beyond the circle of Willis, stent-retrievers, and super-compliant balloons are the result of successful miniaturization of design features and novel manufacturing technologies capable of building these devices. This is a rapidly evolving field, and the device technology enabling such advancements will be reviewed. Importantly, image-guidance technology has not kept pace in neurointervention and the ability to adequately characterize these devices in vivo remains a significant opportunity. Learning Objectives: A survey of devices used in neurointerventions, their materials and essential design characteristics Funding support received from NIH and DOD; Funding support received from GE Healthcare; Funding support received from Siemens AX; Patent royalties received from GE Healthcare; G. Chen, Funding received from NIH; funding received from DOD; funding received from GE Healthcare; funding received from Siemens AX.; M. Gounis, consultant for Codman Neurovascular and Stryker Neurovascular; Holds stock in InNeuroCo Inc, research grants: NIH, Medtronic Neurovascular, Microvention/Terumo, Cerevasc LLC, Gentuity, Codman Neurovascular, Philips Healthcare, Stryker Neurovascular, Tay Sachs Foundation, and InNeuroCo Inc.; S. Rudin, Supported in part by NIH Grant R01EB002873 and the Toshiba Medical System Corp.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2023

CSAPR2 cell-tracking data collected during TRACER

One of the challenges of analyzing convective cell properties is quick evolution of the individual convective cells. While the operational radar data provide great a data set to analyze the evolution of radar observables of convective precipitation clouds statistically, previous studies also suggested that, because of the quick evolution of cell life cycle, conventional radar volume scan strategies taking ~5-7 minutes might not capture the detailed evolution. The TRACER campaign deployed CSAPR2, which performed frequent update of RHI and sector PPI scans to track convective cells every < 2 minutes guided by a new cell-tracking framework, Multisensor Agile Adaptive Sampling (MAAS; Kollias et al. 2020). This allows for capturing fast-evolving radar observables. The submitted data files are CSAPR2 data in CfRadial format collected during the TRACER field campaign from June to September 2020. The data files include processed radar variables including: noise-masked reflectivity and differential reflectivity corrected for rain attenuation and systematic biases, noise-masked dealiased radial velocity, specific differential phase, locations of target cells (latitude, longitude, radar range), and radar-echo classification.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2022

PV Lifetime Project (2021 NREL Annual Report)

DOE's PV Lifetime project was initiated in 2016 with the goal of accurately characterizing the early-life evolution of photovoltaic (PV) field performance. Different PV cell and module technologies result in different initial performance loss rates due to effects like light-induced degradation (LID) and light & elevated temperature-induced degradation (LeTID). To accurately characterize the initial field performance loss requires the use of high-accuracy indoor IV curve measurements at standard test conditions. Therefore, PV modules involved in this study are removed from the field once or twice per year and brought indoors for measurement. Current samples deployed and monitored in this way include Jinko Solar (2016), Trina Solar (2016), Hanwha Q-Cells (2017), Panasonic (2018), LG (2018), Canadian Solar (2018), Mission Solar (2019). More recently, modules from Sunpreme (2019), and LONGi (2020) have been deployed but not yet analyzed. Overall annual performance loss rates are as follows: our first modules to be deployed (Jinko and Trina) have annual median performance loss rate between -0.4%/yr and -0.9%/yr, mainly concentrated in the first year. The QCells mono-PERC and multi-PERC modules have an annual degradation rate of -0.76%/yr and -0.69%/yr respectively, also concentrated in the first year of operation. Panasonic and LG modules displayed negligible performance loss in the past two years, at 0.1%/yr and -0.0%/yr respectively. They also were the only modules with initial IV curve measurements consistently above the nameplate rating. Possibly relatedly, these are also the only two N-type silicon module types analyzed so far. Canadian Solar multi-PERC modules demonstrated a -1.3%/yr degradation rate which actually accelerated in the past year, so this will be a module type to monitor in future years. Mission Solar modules exhibited strong recoverable performance loss, consistent with LeTID susceptibility. (The same is true for the Jinko JKM260 module type). Annual performance loss actually showed improvement in time at +0.3%/yr after 2 years in the field, although the module initially was measured at 3% below nameplate rating. These modules could therefore be experiencing a form of post-LeTID recovery. Initial measurements have been conducted on the next two module types - Sunpreme n-HIT and LONGi bifacial mono-PERC. We will report on initial year-1 performance change for these modules in the next PV Lifetime annual report. For the remaining modules, an additional year of field exposure will provide greater certainty in annual degradation rates, particularly for those with degradation concentrated in the initial year of field deployment.

14 SOLAR ENERGY↗

DOE OSTI2024

Plasma Surface Interactions: Predicting the Performance and Impact of Dynamic PFC Surfaces

The objective of this project is to develop, and integrate, high-performance simulation tools capable of predicting plasma-facing component (PFC) operating lifetime and the impact of the evolving surface morphology of tungsten-based PFCs on plasma contamination, including the dynamic recycling of fuel species and tritium retention, in future magnetic fusion devices. Establishing a fundamental physical understanding and developing predictive capabilities of plasma-surface interactions (PSI) requires simultaneously addressing complex and diverse physics occurring over a wide range of length (Angstroms to meters) and time (femtoseconds to years) scales, as well as integrating extensive physical processes across the plasma–surface interface. This requires development of not only detailed physics models and computational strategies at each scale, but also algorithms and methods to couple them effectively in a way that can be robustly validated. Deploying these tools requires the continued development and coupling of leadership-scale computational codes to describe the boundary plasma and the evolving PFC surface, as well as a host of simulations that bridge disparate scales to address complex physical and computational issues at the plasma–surface interface in multi-component materials systems for magnetic fusion energy development beyond ITER.

36 MATERIALS SCIENCE↗

DOE OSTI2019

The Potential Role of Concentrating Solar Power within the Context of DOE's 2030 Solar Cost Targets

To continue the momentum for cost reduction in solar technologies, DOE recently established 2030 cost targets for that would make solar one of the lowest-cost sources of new electricity in the United States. The potential impacts of achieving the 2030 cost targets for solar photovoltaics (PV) were recently explored in a related publication, which found significant potential for solar PV deployment and generation, particularly when coupled with low-cost storage. Building on this previous report, the present analysis evaluates the potential impacts of simultaneously achieving the 2030 cost targets for both PV and concentrating solar power with thermal energy storage (CSP-TES) systems in the contiguous United States, with a detailed evaluation of the role that CSP-TES plays in realizing those impacts. The evolution of the contiguous U.S. electricity system is evaluated with NREL's Renewable Energy Deployment System (ReEDS) model, which has been specifically designed to represent the time and locational value of renewable generation technologies in the U.S. power system. This analysis suggests achievement of the SunShot cost targets for CSP-TES might lead to dramatic growth in CSP-TES capacity, with accelerated deployment after the 2030 target is achieved. Based on our representation of the 2030 cost targets in ReEDS, economically-competitive CSP-TES could primarily be deployed in a dispatch able, high-capacity factor configuration, which allows it to provide valuable services to the power sector and results in a generation profile for CSP-TES that is complementary to that of variable PV. Aggressive cost reductions for CSP-TES could also make such a configuration economically competitive across the contiguous United States, which is a a result that warrants additional analysis in terms of potential siting, permitting, regulatory, and construction challenges in these new regions and markets. The modeled capacity expansion of both CSP-TES and PV in our scenarios that achieve the 2030 cost targets requires most growth in transmission capacity at a pace that is consistent with historical buildout rates, and could result in reduced electricity prices and power system costs, water usage, and air emissions. Finally, sensitivity analysis suggests that the cumulative capacity and geographic extent of CSP-TES deployment in our low-cost solar scenarios is highly sensitive to the post-2030 cost reductions for CSP-TES and future price of natural gas, and that significant competition exists among renewable energy and energy storage technologies, assuming aggressive cost reductions for each. For example, significant competition between CSP-TES and PV with battery storage indicates the similar role that these systems play in capacity planning and grid operations, as well as the fact that low-cost battery storage would help improve the capacity value of low-cost PV into the future.

14 SOLAR ENERGY↗

DOE OSTI2019

2019 Annual Report of Available Drawdowns for Each Oil Storage Cavern in the Strategic Petroleum Reserve

The Department of Energy maintains an up-to-date documentation of the number of available full drawdowns of each of the caverns owned by the Strategic Petroleum Reserve (SPR). This information is important for assessing the SPR's ability to deliver oil to domestic oil companies expeditiously if national or world events dictate a rapid sale and deployment of the oil reserves. Determining the number of drawdowns requires the consideration of several factors regarding cavern and wellbore integrity and stability, including stress states caused by cavern geometry and operations, salt damage caused by dilatant and tensile stresses, the effect of enhanced creep on wellbore integrity, and the sympathetic stress effect of operations on neighboring caverns. A consensus has now been built regarding the assessment of drawdown capabilities and risks for the SPR caverns (Sobolik et al., 2014; Sobolik 2016). The process involves an initial assessment of the pillar-to-diameter (P/D) ratio for each cavern with respect to neighboring caverns. Ideally, it is desired to keep this value greater than 1.0, which is in line with most industry design standards and should ensure cavern integrity and prevent loss of fluids to the surrounding rock mass. However, many of the SPR caverns currently have a P/D less than 1.0 or will likely have a low P/D after one or two full drawdowns. For these caverns, it is important to examine the structural integrity with more detail using geomechanical models. Finite-element geomechanical models have been used to determine the stress states in the pillars following successive drawdowns. By computing the tensile and dilatant stresses in the salt, areas of potential structural instability can be identified that may represent "red flags" for additional drawdowns. These analyses have found that many caverns will maintain structural integrity even when grown via drawdowns to dimensions resulting in a P/D of less than 1.0. The analyses have also confirmed that certain caverns should only be completely drawn down one time. As the SPR caverns are utilized and partial drawdowns are performed to remove oil from the caverns (e.g., for occasional oil sales authorized by the Congress or the President), the changes to the cavern volumes caused by these procedures must be tracked and accounted for so that an ongoing assessment of the cavern's drawdown capacity may be continued. A proposed methodology for assessing and tracking the available drawdowns for each cavern was presented in Sobolik et al. (2018). This report includes an update to the baseline drawdowns for each cavern, and provides an initial assessment of the evolution of drawdown expenditure for several caverns

02 PETROLEUM↗

DOE OSTI2016

Hierarchical Inorganic Assemblies for Artificial Photosynthesis

Artificial photosynthesis is an attractive approach for renewable fuel generation because it offers the prospect of a technology suitable for deployment on highly abundant, non-arable land. Recent leaps forward in the development of efficient and durable light absorbers and catalysts for oxygen evolution and the growing attention to catalysts for carbon dioxide activation brings into focus the tasks of hierarchically integrating the components into assemblies for closing of the photosynthetic cycle. A particular challenge is the efficient coupling of the multi-electron processes of CO 2 reduction and H 2 O oxidation. Among the most important requirements for a complete integrated system are catalytic rates that match the solar flux, efficient charge transport between the various components, and scalability of the photosynthetic assembly on the unprecedented scale of terawatts in order to have impact on fuel consumption. To address these challenges, we have developed in this paper a heterogeneous inorganic materials approach with molecularly precise control of light absorption and charge transport pathways. Oxo-bridged heterobinuclear units with metal-to-metal charge-transfer transitions absorbing deep in the visible act as single photon, single charge transfer pumps for driving multi-electron catalysts. A photodeposition method has been introduced for the spatially directed assembly of nanoparticle catalysts for selective coupling to the donor or acceptor metal of the light absorber. For CO 2 reduction, a Cu oxide cluster is coupled to the Zr center of a ZrOCo light absorber, while coupling of an Ir nanoparticle catalyst for water oxidation to the Co donor affords closing of the photosynthetic cycle of CO 2 conversion by H 2 O to CO and O 2 . Optical, vibrational, and X-ray spectroscopy provide detailed structural knowledge of the polynuclear assemblies. Time resolved visible and rapid-scan FT-IR studies reveal charge transfer mechanisms and transient surface intermediates under photocatalytic conditions for guiding performance improvements. Separation of the water oxidation and carbon dioxide reduction half reactions by a membrane is essential for efficient photoreduction of CO 2 by H 2 O to liquid fuel products. A concept of a macroscale artificial photosystem consisting of arrays of Co oxide–silica core–shell nanotubes is introduced in which each tube operates as a complete, independent photosynthetic unit with built-in membrane separation. The ultrathin amorphous silica shell with embedded molecular wires functions as a proton conducting, molecule impermeable membrane. Photoelectrochemical and transient optical measurements confirm tight control of charge transport through the membrane by the orbital energetics of the wire molecules. Finally, hierarchical arrangement of the components is accomplished by a combination of photodeposition, controlled anchoring, and atomic layer deposition methods.

36 MATERIALS SCIENCE↗

DOE OSTI2016

TH-A-207B-00: Shear-Wave Imaging and a QIBA US Biomarker Update

Imaging of tissue elastic properties is a relatively new and powerful approach to one of the oldest and most important diagnostic tools. Imaging of shear wave speed with ultrasound is has been added to most high-end ultrasound systems. Understanding this exciting imaging mode aiding its most effective use in medicine can be a rewarding effort for medical physicists and other medical imaging and treatment professionals. Assuring consistent, quantitative measurements across the many ultrasound systems in a typical imaging department will constitute a major step toward realizing the great potential of this technique and other quantitative imaging. This session will target these two goals with two presentations. A. Basics and Current Implementations of Ultrasound Imaging of Shear Wave Speed and Elasticity - Shigao Chen, Ph.D. Learning objectives-To understand: Introduction: Importance of tissue elasticity measurement Strain vs. shear wave elastography (SWE), beneficial features of SWE The link between shear wave speed and material properties, influence of viscosity Generation of shear waves External vibration (Fibroscan) ultrasound radiation force Point push Supersonic push (Aixplorer) Comb push (GE Logiq E9) Detection of shear waves Motion detection from pulse-echo ultrasound Importance of frame rate for shear wave imaging Plane wave imaging detection How to achieve high effective frame rate using line-by-line scanners Shear wave speed calculation Time to peak Random sample consensus (RANSAC) Cross correlation Sources of bias and variation in SWE Tissue viscosity Transducer compression or internal pressure of organ Reflection of shear waves at boundaries B. Elasticity Imaging System Biomarker Qualification and User Testing of Systems – Brian Garra, M.D. Learning objectives-To understand: Goals Review the need for quantitative medical imaging Provide examples of quantitative imaging biomarkers Acquaint the participant with the purpose of the RSNA Quantitative Imaging Biomarker Alliance and the need for such an organization Review the QIBA process for creating a quantitative biomarker Summarize steps needed to verify adherence of site, operators, and imaging systems to a QIBA profile Underlying Premise and Assumptions Objective, quantifiable results are needed to enhance the value of diagnostic imaging in clinical practice Reasons for quantification Evidence based medicine requires objective, not subjective observer data Computerized decision support tools (eg CAD) generally require quantitative input. Quantitative, reproducible measures are more easily used to develop personalized molecular medical diagnostic and treatment systems What is quantitative imaging? Definition from Imaging Metrology Workshop The Quantitative Imaging Biomarker Alliance Formation 2008 Mission Structure Example Imaging Biomarkers Being Explored Biomarker Selection Groundwork Draft Protocol for imaging and data evaluation QIBA Profile Drafting Equipment and Site Validation Technical Clinical Site and Equipment QA and Compliance Checking Ultrasound Elasticity Estimation Biomarker US Elasticity Estimation Background Current Status and Problems Biomarker Selection-process and outcome US SWS for Liver Fibrosis Biomarker Work Groundwork Literature search and analysis results Phase I phantom testing-Elastic phantoms Phase II phantom testing-Viscoelastic phantoms Digital Simulated Data Protocol and Profile Drafting Protocol: based on UPICT and existing literature and standards bodies protocols Profile-Current claims, Manufacturer specific appendices What comes after the profile Profile Validation Technical validation Clinical validation QA and Compliance Possible approaches Site Operator testing Site protocol re-evaluation Imaging system Manufacturer testing and attestation User acceptance testing and periodic QA Phantom Tests Digital Phantom Based Testing Standard QA Testing Remediation Schemes Profile Evolution Towards additional applications Towards higher accuracy and precision Supported in part by NIH contract HHSN268201300071C from NIBIB. Collaboration with GE Global Research, no personal support.; S. Chen, Some technologies described in this presentation have been licensed. Mayo Clinic and Dr. Chen have financial interests these technologies.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2016

TH-A-207B-01: Basics and Current Implementations of Ultrasound Imaging of Shear Wave Speed and Elasticity

Imaging of tissue elastic properties is a relatively new and powerful approach to one of the oldest and most important diagnostic tools. Imaging of shear wave speed with ultrasound is has been added to most high-end ultrasound systems. Understanding this exciting imaging mode aiding its most effective use in medicine can be a rewarding effort for medical physicists and other medical imaging and treatment professionals. Assuring consistent, quantitative measurements across the many ultrasound systems in a typical imaging department will constitute a major step toward realizing the great potential of this technique and other quantitative imaging. This session will target these two goals with two presentations. A. Basics and Current Implementations of Ultrasound Imaging of Shear Wave Speed and Elasticity - Shigao Chen, Ph.D. Learning objectives-To understand: Introduction: Importance of tissue elasticity measurement Strain vs. shear wave elastography (SWE), beneficial features of SWE The link between shear wave speed and material properties, influence of viscosity Generation of shear waves External vibration (Fibroscan) ultrasound radiation force Point push Supersonic push (Aixplorer) Comb push (GE Logiq E9) Detection of shear waves Motion detection from pulse-echo ultrasound Importance of frame rate for shear wave imaging Plane wave imaging detection How to achieve high effective frame rate using line-by-line scanners Shear wave speed calculation Time to peak Random sample consensus (RANSAC) Cross correlation Sources of bias and variation in SWE Tissue viscosity Transducer compression or internal pressure of organ Reflection of shear waves at boundaries B. Elasticity Imaging System Biomarker Qualification and User Testing of Systems – Brian Garra, M.D. Learning objectives-To understand: Goals Review the need for quantitative medical imaging Provide examples of quantitative imaging biomarkers Acquaint the participant with the purpose of the RSNA Quantitative Imaging Biomarker Alliance and the need for such an organization Review the QIBA process for creating a quantitative biomarker Summarize steps needed to verify adherence of site, operators, and imaging systems to a QIBA profile Underlying Premise and Assumptions Objective, quantifiable results are needed to enhance the value of diagnostic imaging in clinical practice Reasons for quantification Evidence based medicine requires objective, not subjective observer data Computerized decision support tools (eg CAD) generally require quantitative input. Quantitative, reproducible measures are more easily used to develop personalized molecular medical diagnostic and treatment systems What is quantitative imaging? Definition from Imaging Metrology Workshop The Quantitative Imaging Biomarker Alliance Formation 2008 Mission Structure Example Imaging Biomarkers Being Explored Biomarker Selection Groundwork Draft Protocol for imaging and data evaluation QIBA Profile Drafting Equipment and Site Validation Technical Clinical Site and Equipment QA and Compliance Checking Ultrasound Elasticity Estimation Biomarker US Elasticity Estimation Background Current Status and Problems Biomarker Selection-process and outcome US SWS for Liver Fibrosis Biomarker Work Groundwork Literature search and analysis results Phase I phantom testing-Elastic phantoms Phase II phantom testing-Viscoelastic phantoms Digital Simulated Data Protocol and Profile Drafting Protocol: based on UPICT and existing literature and standards bodies protocols Profile-Current claims, Manufacturer specific appendices What comes after the profile Profile Validation Technical validation Clinical validation QA and Compliance Possible approaches Site Operator testing Site protocol re-evaluation Imaging system Manufacturer testing and attestation User acceptance testing and periodic QA Phantom Tests Digital Phantom Based Testing Standard QA Testing Remediation Schemes Profile Evolution Towards additional applications Towards higher accuracy and precision Supported in part by NIH contract HHSN268201300071C from NIBIB. Collaboration with GE Global Research, no personal support.; S. Chen, Some technologies described in this presentation have been licensed. Mayo Clinic and Dr. Chen have financial interests these technologies.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2016

TH-A-207B-02: QIBA Ultrasound Elasticity Imaging System Biomarker Qualification and User Testing of Systems

Imaging of tissue elastic properties is a relatively new and powerful approach to one of the oldest and most important diagnostic tools. Imaging of shear wave speed with ultrasound is has been added to most high-end ultrasound systems. Understanding this exciting imaging mode aiding its most effective use in medicine can be a rewarding effort for medical physicists and other medical imaging and treatment professionals. Assuring consistent, quantitative measurements across the many ultrasound systems in a typical imaging department will constitute a major step toward realizing the great potential of this technique and other quantitative imaging. This session will target these two goals with two presentations. A. Basics and Current Implementations of Ultrasound Imaging of Shear Wave Speed and Elasticity - Shigao Chen, Ph.D. Learning objectives-To understand: Introduction: Importance of tissue elasticity measurement Strain vs. shear wave elastography (SWE), beneficial features of SWE The link between shear wave speed and material properties, influence of viscosity Generation of shear waves External vibration (Fibroscan) ultrasound radiation force Point push Supersonic push (Aixplorer) Comb push (GE Logiq E9) Detection of shear waves Motion detection from pulse-echo ultrasound Importance of frame rate for shear wave imaging Plane wave imaging detection How to achieve high effective frame rate using line-by-line scanners Shear wave speed calculation Time to peak Random sample consensus (RANSAC) Cross correlation Sources of bias and variation in SWE Tissue viscosity Transducer compression or internal pressure of organ Reflection of shear waves at boundaries B. Elasticity Imaging System Biomarker Qualification and User Testing of Systems – Brian Garra, M.D. Learning objectives-To understand: Goals Review the need for quantitative medical imaging Provide examples of quantitative imaging biomarkers Acquaint the participant with the purpose of the RSNA Quantitative Imaging Biomarker Alliance and the need for such an organization Review the QIBA process for creating a quantitative biomarker Summarize steps needed to verify adherence of site, operators, and imaging systems to a QIBA profile Underlying Premise and Assumptions Objective, quantifiable results are needed to enhance the value of diagnostic imaging in clinical practice Reasons for quantification Evidence based medicine requires objective, not subjective observer data Computerized decision support tools (eg CAD) generally require quantitative input. Quantitative, reproducible measures are more easily used to develop personalized molecular medical diagnostic and treatment systems What is quantitative imaging? Definition from Imaging Metrology Workshop The Quantitative Imaging Biomarker Alliance Formation 2008 Mission Structure Example Imaging Biomarkers Being Explored Biomarker Selection Groundwork Draft Protocol for imaging and data evaluation QIBA Profile Drafting Equipment and Site Validation Technical Clinical Site and Equipment QA and Compliance Checking Ultrasound Elasticity Estimation Biomarker US Elasticity Estimation Background Current Status and Problems Biomarker Selection-process and outcome US SWS for Liver Fibrosis Biomarker Work Groundwork Literature search and analysis results Phase I phantom testing-Elastic phantoms Phase II phantom testing-Viscoelastic phantoms Digital Simulated Data Protocol and Profile Drafting Protocol: based on UPICT and existing literature and standards bodies protocols Profile-Current claims, Manufacturer specific appendices What comes after the profile Profile Validation Technical validation Clinical validation QA and Compliance Possible approaches Site Operator testing Site protocol re-evaluation Imaging system Manufacturer testing and attestation User acceptance testing and periodic QA Phantom Tests Digital Phantom Based Testing Standard QA Testing Remediation Schemes Profile Evolution Towards additional applications Towards higher accuracy and precision Supported in part by NIH contract HHSN268201300071C from NIBIB. Collaboration with GE Global Research, no personal support.; S. Chen, Some technologies described in this presentation have been licensed. Mayo Clinic and Dr. Chen have financial interests these technologies.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2017

Quantum break-time of de Sitter

The quantum break-time of a system is the time-scale after which its true quantum evolution departs from the classical mean field evolution. For capturing it, a quantum resolution of the classical background—e.g., in terms of a coherent state—is required. In this paper, we first consider a simple scalar model with anharmonic oscillations and derive its quantum break-time. Next, following [1], we apply these ideas to de Sitter space. We formulate a simple model of a spin-2 field, which for some time reproduces the de Sitter metric and simultaneously allows for its well-defined representation as quantum coherent state of gravitons. The mean occupation number N of background gravitons turns out to be equal to the de Sitter horizon area in Planck units, while their frequency is given by the de Sitter Hubble parameter. In the semi-classical limit, we show that the model reproduces all the known properties of de Sitter, such as the redshift of probe particles and thermal Gibbons-Hawking radiation, all in the language of quantum S -matrix scatterings and decays of coherent state gravitons. Most importantly, this framework allows to capture the 1/ N -effects to which the usual semi-classical treatment is blind. They violate the de Sitter symmetry and lead to a finite quantum break-time of the de Sitter state equal to the de Sitter radius times N . We also point out that the quantum-break time is inversely proportional to the number of particle species in the theory. Thus, the quantum break-time imposes the following consistency condition: older and species-richer universes must have smaller cosmological constants. For the maximal, phenomenologically acceptable number of species, the observed cosmological constant would saturate this bound if our Universe were 10{sup 100} years old in its entire classical history.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2018

The D and D of Nuclear Facilities: a Systemic Approach for Project Organization and Monitoring - 18099

The Decontamination and Decommissioning (D and D) of Licensed Nuclear facilities takes place under circumstances which make it a very complex field. On the one hand, more and more facilities of widely varying types are concerned, and many D and D projects are currently running or planned. A nuclear facility's life cycle is often very long and the building may be modified or impacted by incidents during its operation. These changes need to be known and taken into account for the D and D plans, in order to ensure safety at all times. In addition, the numerous stakeholders involved in a project express needs which impose many requirements. These encompass various points of view, and data from different detail levels must be managed to satisfactorily meet them. On the other hand, legacy data (including records, plans etc.) is a recurring issue for D and D projects. The quality and availability of relevant data regarding the different phases of the nuclear facility lifetime may be insufficient, for instance due to the lack of traceability practices in the past. The uncertainty level is not always specified and explained, old documents can be damaged and are not necessarily digitized, etc. It is therefore particularly important to define the relevant type of raw data to be collected and traced for D and D projects as early as possible. In this context, CEA (Commissariat a l'energie Atomique et aux energies Alternatives) has been analyzing past D and D projects for many years. The goal is to facilitate reproducibility by generalizing best practices and promoting efficient organizational rules and technical solutions. A method is currently being studied to help project managers to prepare specifications for future D and D operations and improve both the efficiency and the relevance of the decommissioning strategy throughout each project, depending on the expected quality of its end-state. This method first consists in formalizing and specifying the entire set of requirements to be taken into consideration, e.g. technical, operational, logistical, regulatory, financial, organizational, safety and security, human, ethical, or, naturally, environmental aspects. Second, based on these requirements, it will enable the project team to structure, check, and then to demonstrate the coherence and feasibility of the project from both the technological and organizational points of view. Lastly, the method will enable the evaluation of the various possible solutions for the management of dismantling products, for instance, regarding the waste outlets: direct disposal or interim storage. To conclude, the method should permit a constant re-evaluation of the D and D strategy depending on the possible evolution of the stakeholders' requirements, and thus it should optimize the monitoring of D and D projects. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2021

Investigations of the stability of etched or platinized p-InP(100) photocathodes for solar-driven hydrogen evolution in acidic or alkaline aqueous electrolytes

Here, the stability of p-InP photocathodes performing the hydrogen-evolution reaction (HER) has been evaluated in contact with either 1.0 M H 2 SO 4 (aq) or 1.0 M KOH(aq), with a focus on identifying corrosion mechanisms. Stability for the solar-driven HER was evaluated using p-InP electrodes that were either etched or coated with an electrodeposited Pt catalyst (p-InP/Pt). Variables such as trace O 2 were systematically controlled during the measurements. Changes in surface characteristics after exposure to electrochemical conditions as well as electrode dissolution processes were monitored using X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma mass spectrometry (ICP-MS). In either H 2 SO 4 or KOH, etched p-InP photoelectrodes corroded cathodically under illumination, forming metallic In 0 at the electrode surface. In contrast, electrodeposition of Pt kinetically stabilized illuminated p-InP photocathodes in both H 2 SO 4 and KOH by inhibiting the cathodic corrosion pathway. Notably, when held at 0 V vs. the reversible hydrogen electrode (RHE) in 1.0 M H 2 SO 4 (aq), p-InP/Pt exhibited a stable current density (J) of ~–18 mA cm –2 for >285 h under simulated 1 Sun illumination. The long-term current density vs. potential (J–E) behavior at pH 0 and pH 14 of p-InP/Pt photocathodes correlated with changes in the surface chemistry as well as the dissolution of p-InP. In acidic media, the J–E behavior of p-InP/Pt photocathodes remained nearly constant with time, but the surface of a p-InP/Pt electrodes gradually turned P-rich via a slow and continuous leaching of In ions. In alkaline electrolyte, the surface of p-InP/Pt electrodes was passivated by formation of an InO x layer that exhibited negligible dissolution but led to a substantial degradation in the J–E characteristics. Consequently, changes in the catalytic kinetics and surface stoichiometry are both important considerations for determining the corrosion chemistry and the long-term operational stability of InP photoelectrodes.

14 SOLAR ENERGY↗