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All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Processing of hollow sections

A system and method provide a material with uniform micro-structure. In an embodiment, an equal channel angular extrusion system includes an interior mandrel. The interior mandrel includes an expanding shear material section and a contracting shear material section. In addition, the system includes a material. The material is disposed about a portion of the interior mandrel. Moreover, the system includes a pressure application device. The pressure application device applies pressure to the material to force the material to contact the expanding shear material section to provide an expanded post-shear material section. Pressure from the pressure application device applies pressure to the material to force the expanded post-shear material section to contact the contracting shear material section to provide a contracted shear material section.

Barber, Robert E.↗
DOE OSTI2023

Projecting Future Colorado River Basin Water and Hydropower Operations

Drought, variable renewable energy (VRE) resources (primarily wind and photovoltaic technologies), and power markets can all impact hydropower plant operations. We analyze how these three factors collectively may potentially change the future operation and economics of federal dams and hydropower plants located in the Colorado River Basin (CRB). Federal CRB energy and capacity resources, including 4,200 MW of hydropower capacity, are marketed by Western Area Power Administration (WAPA) and sold through long-term Firm Electric Service (FES) contracts to entities located in 15 western and central States that serve millions of electricity consumers. The parameters of FES contracts allow a wide range of scheduling flexibility for FES customers. The FES customers will adjust the timing of energy delivery according to the changing water, power market, and VRE contribution level to the power grid. We simulate and project water and hydropower operations with two models: 1) reservoir operation and 2) power system operation (production cost) with various temporal granularity. We consider two sets of grid scenarios (one representing today's infrastructure, and one representing higher VRE contributions in 2036) and two sets of water scenarios (drought and normal hydrology). We modeled scenarios to understand the power market-energy price levels and patterns, FES customer scheduling, hydropower economics, WAPA finances and hydropower operation for various hydrologic conditions, and VRE contribution level to the power grid. The detailed modeling framework includes: (1) creating ensembles of CRB hydrologic and hydropower futures, (2) selecting representative futures, (3) simulation of FES customer contracts, (4) simulating western U.S. power grid economic scheduling and dispatch under two VRE contribution levels, utilizing information from modeling steps (1)-(4), (5) assessment of reservoir water and hydropower operation, and (6) comparing scenario operations and economics. Our study team comprising WAPA, and an interdisciplinary team of national labs will gain insight into how WAPA can prepare for and adapt its practices in response to an evolving U.S. power grid.

Colorado River↗
DOE OSTI2011

Visualization of bacteriophage P1 infection by cryo-electron tomography of tiny Escherichia coli

Bacteriophage P1 has a contractile tail that targets the conserved lipopolysaccharide on the outer membrane surface of the host for initial adsorption. The mechanism by which P1 DNA enters the host cell is not well understood, mainly because the transient molecular interactions between bacteriophage and bacteria have been difficult to study by conventional approaches. Here, we engineered tiny E. coli host cells so that the initial stages of P1-host interactions could be captured in unprecedented detail by cryo-electron tomography. Analysis of three-dimensional reconstructions of frozen-hydrated specimens revealed three predominant configurations: an extended tail stage with DNA present in the phage head, a contracted tail stage with DNA, and a contracted tail stage without DNA. Comparative analysis of various conformations indicated that there is uniform penetration of the inner tail tube into the E. coli periplasm and a significant movement of the baseplate away from the outer membrane during tail contraction.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2012

Operation of Bubblers in the Savannah River Site Defense Waste Processing Facility Melter - 12166

Savannah River Remediation (SRR) LLC acquired the liquid waste contract at the Savannah River Site (SRS) in the summer of 2009. In order to achieve the main goal of the contract, closing of High Level Waste (HLW) tanks, it was necessary to process more waste throughout the SRS liquid waste facilities. The Defense Waste Processing Facility (DWPF) would need to increase its production rate of radioactive waste glass filled canisters as a part of the plan to achieve this commitment. To attain the increased production rate, four bubblers were installed in the DWPF Melter in September 2010 to agitate the DWPF Melter glass pool. The four bubblers were designed to be installed in existing nozzles on the top-head of the DWPF Melter. The design and fabrication of the four (4) bubblers was accomplished through SRR critical subcontractor EnergySolutions LLC. In addition to the existing bubbler design, a new design concept has been approved and is in the process of fabrication. The new design will allow for the lower end (inside melter) of the bubbler to be replaced while the upper end (outside melter) of the bubbler is reused to minimize cost and waste at the DWPF. The bubblers have been operating in the DWPF Melter for approximately 1 year. The originally installed bubbler set was replaced in January 2011. The bubblers were visually examined once removed from the melter and showed minimal signs of wear. Material testing of the Inconel 690 is being performed to determine if the bubblers operational life can be extended. The use of the bubblers has changed the dynamics within the melter glass pool. This is shown through indications that the bubblers have increased the glass pool circulation. Overall, performance of the bubblers has been encouraging and the DWPF Melter has seen a significant improvement in its ability to process waste since the bubbler installation. The installation of the bubblers accomplished the goal of increasing the glass production capability of DWPF Melter. Currently the DWPF Melter is producing glass at a rate of 91 to 93 kg of glass/hour (200 to 205 lbs of glass/hour). As a result of this increased glass production rate the DWPF has been able to produce the most canisters since radioactive operations began in 1996. These accomplishments can be directly attributed to the bubblers ability to increase mixing/convection within the glass melt pool thereby improving the heat transfer from melt pool to the cold cap. Further, this has helped SRR take a significant step forward toward closing the HLW tanks at the aggressive pace set forth in the most recent liquid waste contract at the SRS. As a path forward, the DWPF is continuing work with SRNL to complete the final metallurgical examination of the bubbler samples to help determine methods to increase the design life of the bubblers beyond the current 6-month restriction. Also, the DWPF is continuing work with EnergySolutions on a new bubbler design concept to minimize cost and waste at the DWPF. The new design will allow for the lower end (inside melter) of the bubbler to be replaced while the upper end (outside melter) of the bubbler is reused. This new design is currently in the final design approval phase and EnergySolutions will be selecting a fabricator to begin the work to build bubbler sets 5 and 6 using the new design. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2012

Lessons Learned from a Complex FUSRAP Site - Sylvania Corning FUSRAP Site - 12269

Since its addition to the Formerly Utilized Sites Remedial Action Program (FUSRAP) in 2005, the Sylvania Corning FUSRAP Site (the Site) in Hicksville, New York, has provided challenges and opportunities from which to gain lessons learned for conducting investigation work at a complex multi-contaminant FUSRAP Site. The United States Army Corps of Engineers (USACE) and its contractors conducted a Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) Remedial Investigation (RI) and are currently in the Feasibility Study (FS) phase at the Site. This paper presents the planning, execution, and reporting lessons learned by USACE during the RI/FS. The Site, operated from 1952 to 1967 for the research, development, and fabrication of nuclear elements under the Atomic Energy Commission, and other government and commercial contracts. Previous investigations performed by the New York State Department of Environmental Conservation (NYSDEC) and the current property owner have identified uranium, thorium, nickel, and chlorinated solvents, as Site contaminants [1]. The property owner is currently under two separate voluntary agreements with NYSDEC to investigate and remediate the Site. USACE's work at the site has been independent of this voluntary agreement and has moved on a parallel path with any work the property owner has completed. The project at the Site is complex because of the radiological and chemical concerns in both soils and groundwater, high hydraulically conductive soils, lack of a shallow aquiclude/aquitard, and a principal water table aquifer underlying the site. Contaminants are migrating from the Site and may potentially impact local drinking water supplies (municipal wells). During the RI/FS process the project team has encountered many issues and has thus developed many resolutions. The issues are organized into three categories: Planning and Contracting, Execution, and Reporting. Planning and Contracting lessons learned include: how to incorporate an overwhelming volume of historical data; how to manage a complex team of three prime contractors innovatively, and how to implement a project under an Award Fee task order. Execution lessons learned include: characterization of investigation derived wastes, and proper approach to radiological scanning of direct-push borings and soil cores. Reporting lessons learned include: coordinating multiple phase (iterative) reporting, large dataset presentation, and the National Priorities List (NPL) designation. The goal of this paper is to provide a resource for other project delivery teams that encounter similar situations on their projects to optimize cost savings, realization of efficiency, shorten schedules, or simply ensure higher quality deliverables. Each FUSRAP project is unique but there are many lessons we can apply to each site to gain efficiency and work more effectively. The Sylvania Corning FUSRAP site is a complex site with both soils and groundwater contamination, contamination to depths of 182 meters, and a highly politically charged environment of PRP involvement. Many of the lessons the project team has learned during the life of the project to date are being shared with others as well as being applied back to this project for future work. (authors)

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

Deep Borehole Disposal Research in the United States - 17427

The U.S. Department of Energy (DOE) Office of Nuclear Energy (NE) manages a research and development (R and D) program for the disposal of spent nuclear fuel and high-level radioactive waste in the United States. Deep boreholes are being evaluated for disposal of some smaller DOE-managed waste as an alternative to disposal in a mined geologic repository. The deep borehole disposal concept consists of drilling borehole(s) to a total depth of about 5,000 m (16,400 ft - or greater than three miles) into crystalline basement rock, placing waste packages in the lower emplacement zone portion of the borehole, and sealing and plugging the upper portion of the borehole. The required bottom-hole diameter of the borehole(s) depends on the waste package configuration for the reference concept, but ranges from 22 to 43 cm (8.5 to 17 inches). Additional research and development is desired in several important areas for further consideration of deep borehole disposal of radioactive waste. A Deep Borehole Field Test (DBFT) will be conducted by DOE to further assess the viability of deep borehole disposal as an alternative for the disposal of smaller DOE-managed waste forms. The DBFT will be used to evaluate three main areas: 1) evaluation of the capability for drilling and construction of deep, large-diameter boreholes; 2) downhole scientific analyses to assess hydrogeochemical conditions that control waste stability and containment; and 3) engineering activities to assess the viability and safety of waste package emplacement and retrieval in deep boreholes. The DBFT will include first drilling a characterization borehole, followed by an optional field test borehole, to a total depth of about 5,000 m (16,400 feet) into crystalline basement rock in a geologically stable continental location. The initial smaller diameter characterization borehole will be drilled and completed to facilitate downhole scientific testing and analysis. If site conditions are found to be suitable, DOE intends to drill a larger-diameter field test borehole to evaluate emplacement activities using surrogate waste packages. The surrogate waste packages will not contain any radioactive waste, nor will any radioactive waste be used in these tests. One of the advantages of deep borehole disposal is that it would give DOE the flexibility to consider options for disposal of smaller waste forms. Deep borehole disposal also potentially offers earlier disposal of some wastes than might be possible in a mined repository, and could reduce costs associated with projected treatments of some wastes. In order to accomplish the DBFT, DOE will require the support of multiple national laboratories, along with a site contractor to acquire a suitable test site and to manage the site and the required testing activities. DOE issued a competitive solicitation via a request for proposal (RFP) in July, 2015, which requested proposals to provide a test site and site management services. The contract was awarded in January, 2016, to a team led by Battelle Memorial Institute which included a proposed test site in Pierce County, North Dakota. After efforts to acquire both the initial test site in North Dakota and an alternative proposed site in Spink County, South Dakota were unsuccessful, activities were suspended. The experiences in Pierce County, ND and Spink County, SD highlighted the importance of public engagement and support for the DBFT, and that relevant levels of government and other public stakeholders should be involved from the beginning. Using the lessons learned in North and South Dakota, DOE issued a new RFP on August 22, 2016 which emphasized local, state, and tribal (if applicable) government engagement, as well as public and other stakeholder involvement ahead of proposal submittals and throughout the contract execution phases. The new RFP allowed for multiple initial awards and multiple phases of contract execution. In December, 2016, DOE announced the selection of four companies - AECOM, ENERCON, RE/SPEC, and TerranearPMC - to begin exploring the possibility of conducting a DBFT under the terms of the new RFP. Ultimately, only one site will be chosen for the field test. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Environmental cleanup of the East Tennessee Technology Park - Year three - A status report - 15522

On August 1, 2011, URS - CH2M Oak Ridge LLC (UCOR) began its five-year, $1.4 billion cleanup of the East Tennessee Technology Park (ETTP), the former Oak Ridge Gaseous Diffusion Plant, located on the U.S. Department of Energy's (DOE) Oak Ridge Reservation (Reservation) in Tennessee. Under the contract, the base period scope of work to be completed by 2016 includes demolition of both the K-25 and K-31 gaseous diffusion buildings and all demolition waste dispositioned, initiation of demolition on the remaining K-27 gaseous diffusion building, safe storage of transuranic (TRU) waste for eventual transfer to the Transuranic Waste Processing Center, previously designated -No-Path-To-Disposition Waste- dispositioned to the extent possible, and completion of design and engineering of a mercury treatment system to be installed at the Y-12 National Security Complex (Y-12). UCOR will have also managed DOE Oak Ridge Office of Environmental Management (OREM)-owned facilities at ETTP, Oak Ridge National Laboratory (ORNL), and Y-12 in a safe and cost-effective manner. Since assuming responsibilities as the ETTP and Oak Ridge Reservation cleanup contractor, UCOR has completed its life-cycle Performance Measurement Baseline; received its Earned Value Management System (EVMS) certification; completed the deactivation and demolition (D and D) of the 44-acre K-25 gaseous diffusion building; removed and disposed of a contaminated underground storage tank (Tank W-1A) at ORNL; dispositioned mercury-contaminated storage tanks at Y-12; completed closure of the Toxic Substances Control Act Incinerator; disposed of more than 158,000 cubic yards of cleanup waste while managing the on-site Environmental Management Waste Management Facility (EMWMF); and conducted operations, surveillance, and maintenance activities at 180 DOE EM facilities at ETTP, ORNL, and Y-12 in a safe and cost-effective manner. In 2014, UCOR completed the removal and disposal of all of the K-25 demolition debris; completed the removal of asbestos-laden transite siding on the K-31 gaseous diffusion building and began demolition of that 17-acre building; advanced the characterization and deactivation of the K-27 gaseous diffusion building, readying the building for the start of demolition in 2015; advanced the design and engineering of a Mercury Treatment Facility to be located at Y-12; continued the cost-effective and safe disposition of all cleanup wastes; and readied ETTP for Voluntary Protection Program Star Status Assessment in 2015. Project performance as of December 31, 2014, continued to be excellent: - Cost Performance Index - 1.12 - Schedule Performance Index - 1.02 At the same time, since safety is the foundation of all cleanup work, UCOR's safety record goes hand-in-hand with its excellent project performance. Through calendar year 2014, UCOR's recordable injury rate was 1.04 occurrences per 200,000 work hours, and the lost workday case rate was 0.52. This performance continues to be due, in large part, to the people and processes URS and CH2M HILL, the parent companies of UCOR, brought to the project. Key enablers included: - Selected and deployed experienced staff in key leadership positions throughout the organization, continually re-energizing the organization with new leaders - Implemented previously successful safety programs and initiatives from other DOE sites, such as DOE's Voluntary Protection Program - Brought fresh thinking and innovation to tackling tough project issues, such as the deactivation of the Technetium-99-contaminated areas of K-27, applying lessons learned from the D and D of K-25; and implementing a -waste factory- approach to cleanup - Maintained continuing alignment between UCOR's contract with DOE and its Performance Measurement Baseline - rapidly addressing contract changes when they arose - Maintained a readiness both from a process as well as experienced personnel perspective to support DOE OREM in performing other significant Oak Ridge Reservation cleanup activities. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

Progress Updates for the Hanford Waste Treatment and Immobilization Plant Project - 16281

The Waste Treatment and Immobilization Plant (WTP) Project is vital to the U.S. Department of Energy's (DOE) mission to clean up radioactive waste at the Hanford Site, located in southeastern Washington State. The overall WTP Project objective is to design, build, and commission the facilities and systems that will treat and immobilize approximately 56 million gallons of radioactive waste stored in Hanford's 177 underground storage tanks. The combination of technologies in the WTP makes it a first-of-a-kind facility at a scale larger than ever built for radioactive waste processing. The WTP includes several facilities that will contribute to waste processing: (1) the Pretreatment (PT) Facility, which is designed to receive waste retrieved from the Hanford tank farms and separate it into low-activity and high-level waste streams; (2) the Low-Activity Waste (LAW) Facility, which will vitrify the low-activity waste stream; (3) the High-Level Waste (HLW) Facility, which will vitrify the high-level waste stream; (4) the Analytical Laboratory (Lab), which will support both vitrification facilities' operations; and (5) the Balance of Facilities (BOF), which will provide industrial support capabilities and infrastructure, like electricity and steam, needed for WTP operations. In 2012, DOE suspended production work on the WTP's Pretreatment (PT) Facility and to a lesser degree the High-Level Waste (HLW) Facility because of unresolved technical issues associated with those facilities. DOE has established an approach that would facilitate immobilization of tank waste to begin as early as practicable without waiting for completion of work to resolve the technical issues associated with the PT and HLW Facilities. This approach enables LAW treatment to begin before the PT and HLW facilities are completed by transferring low activity waste directly from the Hanford tank farms to the LAW Facility - referred to as Direct Feed LAW (DFLAW). ORP has placed the highest priority on completing the Low Activity Waste Facility, Balance of Facilities, and Analytical Laboratory (collectively known as LBL) in support of the planned phased start to the Hanford Tank waste treatment mission. DOE has requested, and the WTP contractor has delivered contract modifications proposals for: (1) design of a permanent capability to accommodate DFLAW in WTP; (2) procurement and construction of modifications to enable DFLAW operations in WTP, and (3) completion of LBL work scope in the current contract through hot commissioning in a manner to accommodate a phased start toward completing the WTP mission. DOE is reviewing and approving contract modifications in a sequence and schedule that allows for an orderly completion of the LBL Facilities and to begin treating low-activity tank waste as soon as practicable. In August 2014, ORP authorized the WTP contractor to resume all engineering work necessary to finalize the design of the HLW Facility. Authorization for HLW equipment procurements and construction is forthcoming, based on conditions that must be satisfied for a full release of these activities, including completion of an update to the Preliminary Documented Safety Analysis. DOE has also established a comprehensive plan for resuming production activities for the PT Facility that is similar to the process established and implemented for the HLW Facility. Resolution of the technical issues and establishment of a revised safety basis are key prerequisites to resuming engineering, procurements, and construction. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

Improving the Safety Culture by Strengthening Leadership Skills - 16563

As a primary contractor for the U.S. Department of Energy (DOE), CH2M HILL Plateau Remediation Company (CH2M) is managing a team of approximately 1,400 employees at the Hanford Site in Southeast Washington. The work on this 10-year, $5.7 billion contract ranges from design and construction to decommissioning and cleanup. In 2013, CH2M began the second half of its contract and expanded its leadership development program to focus on succession planning and strengthening the leadership skills of its employees. The goal is to create and sustain qualified leaders to lead the Hanford cleanup mission today and into the future. CH2M launched the Leadership Impact Initiative, a training program modeled from best practices used at other CH2M projects, including the Idaho Cleanup Project. Based on the results of a CH2M HILL Plateau Remediation Company site-wide safety culture survey, the company developed an improvement strategy focused on leadership development with emphasis on the front-line leadership. The strategy stresses core leadership principles and skill development to help managers more effectively engage the workforce. The two-day workshop gives employees the opportunity to build leadership on the job in an audience of their peers. CH2M expanded the workshops to include employees from all levels of the organization, including bargaining unit employees. The workshops are reinforced at quarterly all-manager meetings, communications among team members and regular sharing of lessons learned and experiences in the field. The Leadership Impact Initiative advances CH2M's vision of quality leadership and project delivery anchored by health and safety performance excellence. Since 2013, CH2M hosted more than 25 Leadership Impact Initiative workshops, reaching approximately 500 participants. Meanwhile, the company achieved the best safety record since the start of its contract, and results from its 2015 safety culture survey show improvements in the safety climate. A DOE assessment of the CH2M worker health and safety culture for the Voluntary Protection Program (VPP) found the workshop was a contributing factor to the contractor achieving VPP Star and VPP Star of Excellence Status. This paper summarizes the strategy behind the leadership development program, the outcomes and its relevance for other companies, particularly those on DOE Environmental Management decommissioning projects. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

The Magnox Clean-Up Programme - Integrating and Making Best Use of the Supply Chain - 16603

In 2010, the UK Nuclear Decommissioning Authority (NDA) secured a funding settlement of British Pounds 2.5 Bn from the Government for the period to 2015 for the Magnox Care and Maintenance programme. This settlement was a reflection of the importance placed on discharging the decommissioning liability associated with the UK's first generation Magnox reactors. It also reflected the NDA's confidence in the Magnox Optimised Decommissioning Plan (MODP), which aimed to accelerate entry into Care and Maintenance and reduce the Magnox decommissioning liability by British Pounds 1.2 Bn. Despite the settlement, huge challenges remained if the MODP was to be delivered within the funding envelope. Essentially, the supply chain had to be able to participate in the delivery of the MODP and make the investment in skills and techniques required to minimise the threats and uncertainties remaining in the Programme. The Magnox Commercial and Supply Chain Strategy was, therefore, an integral part of the MODP. At the highest level, the Strategy involved: - Classifying and segregating procurements by risk and value - Moving the contracting philosophy from risk transfer to risk management - Focusing on relationships and results rather than activities and processes By aligning the supply chain to the MODP, Magnox was able to better organise itself to deliver against the MODP, to act on feedback from suppliers and enable a culture of 'Lead and Learn' to take root. Using feedback and learning from other organisations and applying these to contract management approaches improved project outcomes. In particular, learning from previous experience of dealing with Programme 'unknowns' increased the company's ability to control and improve on the overall Programme cost and schedule. The impact of the MODP was to reduce the Magnox baseline by over British Pounds 1.5 Bn and remove 34 reactor-years from the Care and Maintenance preparations period. This huge gain resulted from a range of technical, process and commercial improvements across the organisation. Perhaps the greatest achievement of the MODP and its supply chain strategy was to quantify and stabilise the Magnox Life-cycle scope and cost and enable the successful competition and transfer of the Management and Operating (M and O) contract in 2014 and lay the foundations for further cost-savings to the UK taxpayer. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Automated Data Review of Analytical Laboratory Results at Los Alamos National Laboratory - 20299

Newport News Nuclear BWXT-Los Alamos, LLC (N3B) collects samples in support of the U.S. Department of Energy's (DOE) Office of Environmental Management (EM) Los Alamos Legacy Cleanup Contract (LLCC). N3B receives and reviews over 1.6 million sample data points annually in support of various ongoing environmental monitoring and remediation projects of the LLCC. N3B must demonstrate and document that reported external analytical laboratory data produced for the LLCC are of sufficient quality to fulfill their intended purpose and to support defensible decision making as described in EPA QA/G4 Guidance for the Data Quality Objectives Process 1994. In 2018, N3B assumed management of the LLCC along with the Environmental Information Management (EIM) database that contains all historical and current environmental data associated with the LLCC. The entire EIM database is shared between N3B, Triad National Security, LLC (Triad), and New Mexico Environment Department (NMED). These three parties jointly manage the database, its configuration, and changes / updates. All environmental data that are entered into EIM are updated and available, on a daily basis, in the linked public database Intellus New Mexico (Intellus). The quality and defensibility of the environmental data generated from sampling activities is a key component of an effective remediation process. Providing quality data is accomplished through a data assessment process that includes examination, verification, and validation. Examination is the assessment of completeness of the deliverables, identification of any reporting errors, and determining the usability of the data based on the laboratory's evaluation of its data as described in the case narrative received with the data. Verification consists of an evaluation of the Electronic Data Deliverables (EDD) data report to determine the extent to which the external analytical laboratories met method and contract-specific quality control and reporting requirements. Validation consists of determining the data quality and the extent to which the external analytical laboratories accurately and completely reported all sample and quality control results and satisfied all contract requirements. EIM contains an automatic Data Validation Module which performs automated data review (DVM ADR). DVM ADR is a tool to assist in the validation process. When DVM ADR is used in conjunction with manual examination of sample data packages, the combination of the two will meet and exceed the requirements of verification. N3B recognized an opportunity for process improvement, focusing on DVM ADR configuration and enhancements in EIM. Testing EIM's configuration provided proof of the DVM ADR's capabilities and flexibility to accurately perform routine data checks based on analytical methods and regulatory requirements. In addition, the DVM ADR module was improved through enhancements for all analytes, particularly upgrades for radiochemistry data. Extensive testing of the DVM ADR module occurred using EDDs from actual laboratory analyses on the EIM testing site. During this process, N3B manipulated EDD information to verify that the actual outcomes matched the expected outcomes. The results of this testing were shared with the database architects, and configuration improvements were identified to address these results. During this process, N3B identified that the radiochemical DVM ADR capabilities were underutilized, and so enhanced the DVM ADR functionality with respect to radioanalytical assessment. N3B environmental data uploads to Intellus on a daily basis from EIM, once the analytical data undergoes examination and verification. As such, it is important to have a high level of confidence in the quality and defensibility of the data. The process of manual examination, along with the DVM ADR, in conjunction with full validation of a percentage the data specified through the Data Quality Objectives greatly increases efficiency of data review and confidence level of the quality of the data, and gives the project managers, governmental offices, and the public expedited access to high-quality data. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2025

Actuated flywheel projectile launcher

Various embodiments include an actuated projectile launcher, including: a base structure; a projectile support, and a holding area from which a projectile launches; propulsion wheels selectively driven to rotate; and support arms, each supporting at a first end thereof a separate one of the propulsion wheels and being supported at an opposed second end thereof by the base structure. The support arms are configured to move the propulsion wheels between an expanded position and a contracted position, in which the propulsion wheels are closer to one another in the contracted position as compared to the expanded position. The movement of the propulsion wheels toward the contracted position brings the propulsion wheels into engagement with the projectile and drives the projectile from the holding area.

Dullea, Kevin J.↗
DOE OSTI2017

Low-rank factorization of electron integral tensors and its application in electronic structure theory

In this letter, we introduce the reverse Cuthill-McKee (RCM) algorithm, which is often used for the bandwidth reduction of sparse tensors, to transform the two-electron integral tensors to their block diagonal forms. By further applying the pivoted Cholesky decomposition (CD) on each of the diagonal blocks, we are able to represent the high-dimensional two-electron integral tensors in terms of permutation matrices and low-rank Cholesky vectors. This representation facilitates the low-rank factorization of the high-dimensional tensor contractions that are usually encountered in post-Hartree-Fock calculations. In this letter, we discuss the second-order Møller-Plesset (MP2) method and linear coupled- cluster model with doubles (L-CCD) as two simple examples to demonstrate the efficiency of the RCM-CD technique in representing two-electron integrals in a compact form.

electronic structure theory↗
NASA NTRS1992

Muscle fatigue in frog semitendinosus: alterations in contractile function

The purpose of this study was to characterize the contractile properties of the frog semitendinosus (ST) muscle before and during recovery from fatigue, to relate the observed functional changes to alterations in specific steps in the crossbridge model of muscle contraction, and to determine how fatigue affects the force-frequency relationship. The frog ST (22 degrees C) was fatigued by direct electrical stimulation with 100-ms 150-Hz trains at 1/s for 5 min. The fatigue protocol reduced peak twitch (Pt) and tetanic (Po) force to 32 and 8.5% of initial force, respectively. The decline in Pt was less than Po, in part due to a prolongation in the isometric contraction time (CT), which increased to 300% of the initial value. The isometric twitch duration was greatly prolonged as reflected by the lengthened CT and the 800% increase in the one-half relaxation time (1/2RT). Both Pt and Po showed a biphasic recovery, a rapid initial phase (2 min) followed by a slower (40 min) return to the prefatigue force. CT and 1/2RT also recovered in two phases, returning to 160 and 265% of control in the first 5 min. CT returned to the prefatigue value between 35 and 40 min, whereas even at 60 min 1/2RT was 133% of control. The maximal velocity of shortening, determined by the slack test, was significantly reduced [from 6.7 +/- 0.5 to 2.5 +/- 0.4 optimal muscle length/s] at fatigue. The force-frequency relationship was shifted to the left, so that optimal frequency for generating Po was reduced.(ABSTRACT TRUNCATED AT 250 WORDS).

NASA Discipline Musculoskeletal↗
DOE OSTI2023

Convergence analysis of single rate and multirate fixed stress split iterative coupling schemes in heterogeneous poroelastic media

Recently, the accurate modeling of flow–structure interactions has gained more attention and importance for both petroleum and environmental engineering applications. Of particular interest is the coupling between subsurface flow and reservoir geomechanics. Different single rate and multirate iterative and explicit coupling schemes have been proposed and analyzed in the past. In addition, Banach fixed point contraction results were obtained for iterative coupling schemes, and conditionally stable results were obtained for explicit coupling schemes. In this work, we will consider the mathematical analysis of the single rate and multirate fixed stress split iterative coupling schemes for spatially heterogeneous poroelastic media. We will re–establish the contractivity for both schemes in the localized case, and we will show that heterogeneities come at the expense of imposing more restricted conditions on the number of fine flow time steps that can be taken within one coarse mechanics time step in the multirate case. Our mathematical analysis is supplemented by numerical simulations validating our derived upper bounds. Finally, to the best of our knowledge, this is the first rigorous mathematical analysis of the multirate fixed–stress split iterative coupling scheme in heterogeneous poroelastic media.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2021

Symmetry-breaking in double gyroid block copolymer films by non-affine distortion

Soft-matter bicontinuous networks find a double gyroid structure from block copolymer (BCP) self-assembly. A gyroid structure composed of dissimilar blocks has proven its potential as a soft crystal capable of tuning structural periodicity and symmetry, of which the lattice dimension is variable with molecular weight of the polymer. Using an asymmetric polystyrene- b -poly(methyl methacrylate) (PS- b -PMMA), in this study we show that the self-assembled gyroid films formed via a solvent vapor annealing (SVA) process undergo unique structural distortion due to directional deformation immediately upon deswelling. During the SVA process with PS- b -PMMA films, transient cylinders developed from the as-cast morphology transform into a cubic gyroid structure in a swollen state. Rapid and spontaneous deswelling processes -the manners in which the films contract along the z-direction while retaining an enlarged lateral dimension of the cubic form -lead to triclinic gyroid structures with z-directional contraction ratios ( C z ) of 2.5 and 2.0, respectively. Our X-ray analysis reveals that the deswelling process of the swollen gyroid films produces a notable symmetry-breaking in non-affine gyroid structure that elicits several forbidden reflections such as {110} and {200} reflections. For further characterization of the symmetry-breaking, we delineate the structural features of noncubic gyroid films by computing electron-density difference maps assisted with X-ray measurements. Level-set approach is accordingly developed to quantitate the structural characteristics of the maps in terms of inversion symmetry-breaking, suggesting its possible application to optical Weyl photonic crystals.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Platelet-derived growth factor regulates vascular smooth muscle phenotype via mammalian target of rapamycin complex 1

Mammalian target of rapamycin complex (mTORC) regulates various cellular processes including proliferation, growth, migration and differentiation. In this study, we showed that mTORC1 regulates platelet-derived growth factor (PDGF)-induced phenotypic conversion of vascular smooth muscle cells (VSMCs). Stimulation of contractile VSMCs with PDGF significantly reduced the expression of contractile marker proteins in a time- and dose-dependent manner. In addition, angiotensin II (AngII)-induced contraction of VSMCs was completely blocked by the stimulation of VSMCs with PDGF. PDGF-dependent suppression of VSMC marker gene expression was significantly blocked by inhibition of phosphatidylinositol 3-kinase (PI3K), extracellular signal-regulated kinase (ERK), and mTOR whereas inhibition of p38 MAPK had no effect. In particular, inhibition of mTORC1 by rapamycin or by silencing of Raptor significantly blocked the PDGF-dependent phenotypic change of VSMCs whereas silencing of Rictor had no effect. In addition, loss of AngII-dependent contraction by PDGF was significantly retained by silencing of Raptor. Inhibition of mTORC1 by rapamycin or by silencing of Raptor significantly blocked PDGF-induced proliferation of VSMCs. Taken together, we suggest that mTORC1 plays an essential role in PDGF-dependent phenotypic changes of VSMCs. - Graphical abstract: Regulation of VSMC phenotype by PDGF-dependent activation of mTORC1. - Highlights: • The expression of contractile marker proteins was reduced by PDGF stimulation. • PDGF-dependent phenotypic conversion of VSMCs was blocked by inhibition of mTOR. • PDGF-induced proliferation of VSMCs was attenuated by inhibition of mTORC1. • mTORC1 plays a critical role in PDGF-dependent phenotypic conversion of VSMCs.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

GSK3β attenuates TGF-β1 induced epithelial–mesenchymal transition and metabolic alterations in ARPE-19 cells

While TGF-β1 is known to induce epithelial–mesenchymal transition (EMT), a major factor in the pathogenesis of proliferative vitreoretinopathy (PVR), in ARPE-19 cells. The molecular pathways involved in EMT formation have not yet to be fully characterized. In this study, we have found that TGF-β1-mediated induction of EMT in ARPE-19 cells varied in a dose- and time-dependent manner. Specifically, TGF-β1 inhibited GSK-3β by accelerating phosphorylation at ser9. GSK-3β inhibitor or knockdown of GSK-3β resulted in enhanced TGF-β1-mediated EMT, migration and collagen contraction in ARPE-19 cells, which were then abrogated by GSK-3β overexpression and PI3K/AKT inhibitor. Importantly, GSK-3β also mediated metabolic reprogramming in TGF-β1-treated cells. Our results indicate that GSK-3β plays a pivotal role in TGF-β1-mediated EMT in ARPE-19 cells. - Highlights: • GSK-3β mediates epithelial-mesenchymal transition in TGF-β1 treated ARPE-19 cells. • GSK-3β regulates cell migration and collagen contraction of ARPE-19 cells. • TGF-β1 induces extracellular metabolomic changes of ARPE-19 cells via a GSK-3β-dependent mechanism.

60 APPLIED LIFE SCIENCES↗