Fusion Safety Program annual report, fiscal year 1994

NASA Astrophysics Data System (ADS)

Longhurst, Glen R.; Cadwallader, Lee C.; Dolan, Thomas J.; Herring, J. Stephen; McCarthy, Kathryn A.; Merrill, Brad J.; Motloch, Chester C.; Petti, David A.

1995-03-01

This report summarizes the major activities of the Fusion Safety Program in fiscal year 1994. The Idaho National Engineering Laboratory (INEL) is the designated lead laboratory and Lockheed Idaho Technologies Company is the prime contractor for this program. The Fusion Safety Program was initiated in 1979. Activities are conducted at the INEL, at other DOE laboratories, and at other institutions, including the University of Wisconsin. The technical areas covered in this report include tritium safety, beryllium safety, chemical reactions and activation product release, safety aspects of fusion magnet systems, plasma disruptions, risk assessment failure rate data base development, and thermalhydraulics code development and their application to fusion safety issues. Much of this work has been done in support of the International Thermonuclear Experimental Reactor (ITER). Also included in the report are summaries of the safety and environmental studies performed by the Fusion Safety Program for the Tokamak Physics Experiment and the Tokamak Fusion Test Reactor and of the technical support for commercial fusion facility conceptual design studies. A major activity this year has been work to develop a DOE Technical Standard for the safety of fusion test facilities.

Added Value of Contrast-Enhanced Ultrasound on Biopsies of Focal Hepatic Lesions Invisible on Fusion Imaging Guidance

PubMed Central

Kang, Tae Wook; Song, Kyoung Doo; Kim, Mimi; Kim, Seung Soo; Kim, Seong Hyun; Ha, Sang Yun

2017-01-01

Objective To assess whether contrast-enhanced ultrasonography (CEUS) with Sonazoid can improve the lesion conspicuity and feasibility of percutaneous biopsies for focal hepatic lesions invisible on fusion imaging of real-time ultrasonography (US) with computed tomography/magnetic resonance images, and evaluate its impact on clinical decision making. Materials and Methods The Institutional Review Board approved this retrospective study. Between June 2013 and January 2015, 711 US-guided percutaneous biopsies were performed for focal hepatic lesions. Biopsies were performed using CEUS for guidance if lesions were invisible on fusion imaging. We retrospectively evaluated the number of target lesions initially invisible on fusion imaging that became visible after applying CEUS, using a 4-point scale. Technical success rates of biopsies were evaluated based on histopathological results. In addition, the occurrence of changes in clinical decision making was assessed. Results Among 711 patients, 16 patients (2.3%) were included in the study. The median size of target lesions was 1.1 cm (range, 0.5–1.9 cm) in pre-procedural imaging. After CEUS, 15 of 16 (93.8%) focal hepatic lesions were visualized. The conspicuity score was significantly increased after adding CEUS, as compared to that on fusion imaging (p < 0.001). The technical success rate of biopsy was 87.6% (14/16). After biopsy, there were changes in clinical decision making for 11 of 16 patients (68.8%). Conclusion The addition of CEUS could improve the conspicuity of focal hepatic lesions invisible on fusion imaging. This dual guidance using CEUS and fusion imaging may affect patient management via changes in clinical decision-making. PMID:28096725

CONFERENCE REPORT: Summary of the 8th IAEA Technical Meeting on Fusion Power Plant Safety

NASA Astrophysics Data System (ADS)

Girard, J. Ph.; Gulden, W.; Kolbasov, B.; Louzeiro-Malaquias, A.-J.; Petti, D.; Rodriguez-Rodrigo, L.

2008-01-01

Reports were presented covering a selection of topics on the safety of fusion power plants. These included a review on licensing studies developed for ITER site preparation surveying common and non-common issues (i.e. site dependent) as lessons to a broader approach for fusion power plant safety. Several fusion power plant models, spanning from accessible technology to more advanced-materials based concepts, were discussed. On the topic related to fusion-specific technology, safety studies were reported on different concepts of breeding blanket modules, tritium handling and auxiliary systems under normal and accident scenarios' operation. The testing of power plant relevant technology in ITER was also assessed in terms of normal operation and accident scenarios, and occupational doses and radioactive releases under these testings have been determined. Other specific safety issues for fusion have also been discussed such as availability and reliability of fusion power plants, dust and tritium inventories and component failure databases. This study reveals that the environmental impact of fusion power plants can be minimized through a proper selection of low activation materials and using recycling technology helping to reduce waste volume and potentially open the route for its reutilization for the nuclear sector or even its clearance into the commercial circuit. Computational codes for fusion safety have been presented in support of the many studies reported. The on-going work on establishing validation approaches aiming at improving the prediction capability of fusion codes has been supported by experimental results and new directions for development have been identified. Fusion standards are not available and fission experience is mostly used as the framework basis for licensing and target design for safe operation and occupational and environmental constraints. It has been argued that fusion can benefit if a specific fusion approach is implemented, in particular for materials selection which will have a large impact on waste disposal and recycling and in the real limits of radiation releases if indexed to the real impact on individuals and the environment given the differences in the types of radiation emitted by tritium when compared with the fission products. Round table sessions resulted in some common recommendations. The discussions also created the awareness of the need for a larger involvement of the IAEA in support of fusion safety standards development.

EDITORIAL: Safety aspects of fusion power plants

NASA Astrophysics Data System (ADS)

Kolbasov, B. N.

2007-07-01

This special issue of Nuclear Fusion contains 13 informative papers that were initially presented at the 8th IAEA Technical Meeting on Fusion Power Plant Safety held in Vienna, Austria, 10-13 July 2006. Following recommendation from the International Fusion Research Council, the IAEA organizes Technical Meetings on Fusion Safety with the aim to bring together experts to discuss the ongoing work, share new ideas and outline general guidance and recommendations on different issues related to safety and environmental (S&E) aspects of fusion research and power facilities. Previous meetings in this series were held in Vienna, Austria (1980), Ispra, Italy (1983), Culham, UK (1986), Jackson Hole, USA (1989), Toronto, Canada (1993), Naka, Japan (1996) and Cannes, France (2000). The recognized progress in fusion research and technology over the last quarter of a century has boosted the awareness of the potential of fusion to be a practically inexhaustible and clean source of energy. The decision to construct the International Thermonuclear Experimental Reactor (ITER) represents a landmark in the path to fusion power engineering. Ongoing activities to license ITER in France look for an adequate balance between technological and scientific deliverables and complying with safety requirements. Actually, this is the first instance of licensing a representative fusion machine, and it will very likely shape the way in which a more common basis for establishing safety standards and policies for licensing future fusion power plants will be developed. Now that ITER licensing activities are underway, it is becoming clear that the international fusion community should strengthen its efforts in the area of designing the next generations of fusion power plants—demonstrational and commercial. Therefore, the 8th IAEA Technical Meeting on Fusion Safety focused on the safety aspects of power facilities. Some ITER-related safety issues were reported and discussed owing to their potential importance for the fusion power plant research programmes. The objective of this Technical Meeting was to examine in an integrated way all the safety aspects anticipated to be relevant to the first fusion power plant prototype expected to become operational by the middle of the century, leading to the first generation of economically viable fusion power plants with attractive S&E features. After screening by guest editors and consideration by referees, 13 (out of 28) papers were accepted for publication. They are devoted to the following safety topics: power plant safety; fusion specific operational safety approaches; test blanket modules; accident analysis; tritium safety and inventories; decommissioning and waste. The paper `Main safety issues at the transition from ITER to fusion power plants' by W. Gulden et al (EU) highlights the differences between ITER and future fusion power plants with magnetic confinement (off-site dose acceptance criteria, consequences of accidents inside and outside the design basis, occupational radiation exposure, and waste management, including recycling and/or final disposal in repositories) on the basis of the most recent European fusion power plant conceptual study. Ongoing S&E studies within the US inertial fusion energy (IFE) community are focusing on two design concepts. These are the high average power laser (HAPL) programme for development of a dry-wall, laser-driven IFE power plant, and the Z-pinch IFE programme for the production of an economically-attractive power plant using high-yield Z-pinch-driven targets. The main safety issues related to these programmes are reviewed in the paper `Status of IFE safety and environmental activities in the US' by S. Reyes et al (USA). The authors propose future directions of research in the IFE S&E area. In the paper `Recent accomplishments and future directions in the US Fusion Safety & Environmental Program' D. Petti et al (USA) state that the US fusion programme has long recognized that the S&E potential of fusion can be attained by prudent materials selection, judicious design choices, and integration of safety requirements into the design of the facility. To achieve this goal, S&E research is focused on understanding the behaviour of the largest sources of radioactive and hazardous materials in a fusion facility, understanding how energy sources in a fusion facility could mobilize those materials, developing integrated state-of-the-art S&E computer codes and risk tools for safety assessment, and evaluating and improving fusion facility design in terms of accident safety, worker safety, and waste disposal. There are three papers considering safety issues of the test blanket modules (TBM) producing tritium to be installed in ITER. These modules represent different concepts of demonstration fusion power facilities (DEMO). L. Boccaccini et al (Germany) analyses the possibility of jeopardizing the ITER safety under specific accidents in the European helium-cooled pebble-bed TBM, e.g. pressurization of the vacuum vessel (VV), hydrogen production from the Be-steam reaction, the possible interconnection between the port cell and VV causing air ingress. Safety analysis is also presented for Chinese TBM with a helium-cooled solid breeder to be tested in ITER by Z. Chen et al (China). Radiological inventories, afterheat, waste disposal ratings, electromagnetic characteristics, LOCA and tritium safety management are considered. An overview of a preliminary safety analysis performed for a US proposed TBM is presented by B. Merrill et al (USA). This DEMO relevant dual coolant liquid lead-lithium TBM has been explored both in the USA and EU. T. Pinna et al (Italy) summarize the six-year development of a failure rate database for fusion specific components on the basis of data coming from operating experience gained in various fusion laboratories. The activity began in 2001 with the study of the Joint European Torus vacuum and active gas handling systems. Two years later the neutral beam injectors and the power supply systems were considered. This year the ion cyclotron resonant heating system is under evaluation. I. Cristescu et al (Germany) present the paper `Tritium inventories and tritium safety design principles for the fuel cycle of ITER'. She and her colleagues developed the dynamic mathematical model (TRIMO) for tritium inventory evaluation within each system of the ITER fuel cycle in various operational scenarios. TRIMO is used as a tool for trade-off studies within the fuel cycle systems with the final goal of global tritium inventory minimization. M. Matsuyama et al (Japan) describes a new technique for in situ quantitative measurements of high-level tritium inventory and its distribution in the VV and tritium systems of ITER and future fusion reactors. This technique is based on utilization of x-rays induced by beta-rays emitting from tritium species. It was applied to three physical states of high-level tritium: to gaseous, aqueous and solid tritium retained on/in various materials. Finally, there are four papers devoted to safety issues in fusion reactor decommissioning and waste management. A paper by R. Pampin et al (UK) provides the revised radioactive waste analysis of two models in the PPCS. Another paper by M. Zucchetti (Italy), S.A. Bartenev (Russia) et al describes a radiochemical extraction technology for purification of V-Cr-Ti alloy components from activation products to the dose rate of 10 µSv/h allowing their clearance or hands-on recycling which has been developed and tested in laboratory stationary conditions. L. El-Guebaly (USA) and her colleagues submitted two papers. In the first paper she optimistically considers the possibility of replacing the disposal of fusion power reactor waste with recycling and clearance. Her second paper considers the implications of new clearance guidelines for nuclear applications, particularly for slightly irradiated fusion materials.

Materials and fabrication technology of modules intended for irradiation tests of blanket tritium-breeding zones in Russian fusion reactor projects

NASA Astrophysics Data System (ADS)

Kapychev, V.; Davydov, D.; Gorokhov, V.; Ioltukhovskiy, A.; Kazennov, Yu; Tebus, V.; Frolov, V.; Shikov, A.; Shishkov, N.; Kovalenko, V.; Shishkin, N.; Strebkov, Yu

2000-12-01

This paper surveys the modules and materials of blanket tritium-breeding zones developed in the Russian Federation for fusion reactors. Synthesis of lithium orthosilicate, metasilicate and aluminate, fabrication of ceramic pellets and pebbles and experimental reactor units are described. Results of tritium extraction kinetics under irradiation in a water-graphite reactor at a thermal neutron flux of 5×10 13 neutron/(s cm2) are considered. At the present time, development and fabrication of lithium orthosilicate-beryllium modules of the tritium-breeding zone (TBZ), have been carried out within the framework of the ITER and DEMO projects. Two modules containing orthosilicate pellets, porous beryllium and beryllium pebbles are suggested for irradiation tests in the temperature range of 350-700°C. Technical problems associated with manufacturing of the modules are discussed.

Magnet Design Considerations for Fusion Nuclear Science Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhai, Y.; Kessel, C.; El-Guebaly, L.

2016-06-01

The Fusion Nuclear Science Facility (FNSF) is a nuclear confinement facility that provides a fusion environment with components of the reactor integrated together to bridge the technical gaps of burning plasma and nuclear science between the International Thermonuclear Experimental Reactor (ITER) and the demonstration power plant (DEMO). Compared with ITER, the FNSF is smaller in size but generates much higher magnetic field, i.e., 30 times higher neutron fluence with three orders of magnitude longer plasma operation at higher operating temperatures for structures surrounding the plasma. Input parameters to the magnet design from system code analysis include magnetic field of 7.5more » T at the plasma center with a plasma major radius of 4.8 m and a minor radius of 1.2 m and a peak field of 15.5 T on the toroidal field (TF) coils for the FNSF. Both low-temperature superconductors (LTS) and high-temperature superconductors (HTS) are considered for the FNSF magnet design based on the state-of-the-art fusion magnet technology. The higher magnetic field can be achieved by using the high-performance ternary restacked-rod process Nb3Sn strands for TF magnets. The circular cable-in-conduit conductor (CICC) design similar to ITER magnets and a high-aspect-ratio rectangular CICC design are evaluated for FNSF magnets, but low-activation-jacket materials may need to be selected. The conductor design concept and TF coil winding pack composition and dimension based on the horizontal maintenance schemes are discussed. Neutron radiation limits for the LTS and HTS superconductors and electrical insulation materials are also reviewed based on the available materials previously tested. The material radiation limits for FNSF magnets are defined as part of the conceptual design studies for FNSF magnets.« less

Magnet design considerations for Fusion Nuclear Science Facility

DOE PAGES

Zhai, Yuhu; Kessel, Chuck; El-guebaly, Laila; ...

2016-02-25

The Fusion Nuclear Science Facility (FNSF) is a nuclear confinement facility to provide a fusion environment with components of the reactor integrated together to bridge the technical gaps of burning plasma and nuclear science between ITER and the demonstration power plant (DEMO). Compared to ITER, the FNSF is smaller in size but generates much higher magnetic field, 30 times higher neutron fluence with 3 orders of magnitude longer plasma operation at higher operating temperatures for structures surrounding the plasma. Input parameters to the magnet design from system code analysis include magnetic field of 7.5 T at the plasma center withmore » plasma major radius of 4.8 m and minor radius of 1.2 m, and a peak field of 15.5 T on the TF coils for FNSF. Both low temperature superconductor (LTS) and high temperature superconductor (HTS) are considered for the FNSF magnet design based on the state-of-the-art fusion magnet technology. The higher magnetic field can be achieved by using the high performance ternary Restack Rod Process (RRP) Nb3Sn strands for toroidal field (TF) magnets. The circular cable-in-conduit conductor (CICC) design similar to ITER magnets and a high aspect ratio rectangular CICC design are evaluated for FNSF magnets but low activation jacket materials may need to be selected. The conductor design concept and TF coil winding pack composition and dimension based on the horizontal maintenance schemes are discussed. Neutron radiation limits for the LTS and HTS superconductors and electrical insulation materials are also reviewed based on the available materials previously tested. As a result, the material radiation limits for FNSF magnets are defined as part of the conceptual design studies for FNSF magnets.« less

FUSION ENERGY SCIENCES WORKSHOP ON PLASMA MATERIALS INTERACTIONS: Report on Science Challenges and Research Opportunities in Plasma Materials Interactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maingi, Rajesh; Zinkle, Steven J.; Foster, Mark S.

2015-05-01

The realization of controlled thermonuclear fusion as an energy source would transform society, providing a nearly limitless energy source with renewable fuel. Under the auspices of the U.S. Department of Energy, the Fusion Energy Sciences (FES) program management recently launched a series of technical workshops to “seek community engagement and input for future program planning activities” in the targeted areas of (1) Integrated Simulation for Magnetic Fusion Energy Sciences, (2) Control of Transients, (3) Plasma Science Frontiers, and (4) Plasma-Materials Interactions aka Plasma-Materials Interface (PMI). Over the past decade, a number of strategic planning activities1-6 have highlighted PMI and plasmamore » facing components as a major knowledge gap, which should be a priority for fusion research towards ITER and future demonstration fusion energy systems. There is a strong international consensus that new PMI solutions are required in order for fusion to advance beyond ITER. The goal of the 2015 PMI community workshop was to review recent innovations and improvements in understanding the challenging PMI issues, identify high-priority scientific challenges in PMI, and to discuss potential options to address those challenges. The community response to the PMI research assessment was enthusiastic, with over 80 participants involved in the open workshop held at Princeton Plasma Physics Laboratory on May 4-7, 2015. The workshop provided a useful forum for the scientific community to review progress in scientific understanding achieved during the past decade, and to openly discuss high-priority unresolved research questions. One of the key outcomes of the workshop was a focused set of community-initiated Priority Research Directions (PRDs) for PMI. Five PRDs were identified, labeled A-E, which represent community consensus on the most urgent near-term PMI scientific issues. For each PRD, an assessment was made of the scientific challenges, as well as a set of actions to address those challenges. No prioritization was attempted amongst these five PRDs. We note that ITER, an international collaborative project to substantially extend fusion science and technology, is implicitly a driver and beneficiary of the research described in these PRDs; specific ITER issues are discussed in the background and PRD chapters. For succinctness, we describe these PRDs directly below; a brief introduction to magnetic fusion and the workshop process/timeline is given in Chapter I, and panelists are listed in the Appendix.« less

The status of beryllium technology for fusion

NASA Astrophysics Data System (ADS)

Scaffidi-Argentina, F.; Longhurst, G. R.; Shestakov, V.; Kawamura, H.

2000-12-01

Beryllium was used for a number of years in the Joint European Torus (JET), and it is planned to be used extensively on the lower heat-flux surfaces of the reduced technical objective/reduced cost international thermonuclear experimental reactor (RTO/RC ITER). It has been included in various forms in a number of tritium breeding blanket designs. There are technical advantages but also a number of safety issues associated with the use of beryllium. Research in a variety of technical areas in recent years has revealed interesting issues concerning the use of beryllium in fusion. Progress in this research has been presented at a series of International Workshops on Beryllium Technology for Fusion. The most recent workshop was held in Karlsruhe, Germany on 15-17 September 1999. In this paper, a summary of findings presented there and their implications for the use of beryllium in the development of fusion reactors are presented.

Bonding and fusion of meniscus fibrocartilage using a novel chondroitin sulfate bone marrow tissue adhesive.

PubMed

Simson, Jacob A; Strehin, Iossif A; Allen, Brian W; Elisseeff, Jennifer H

2013-08-01

The weak intrinsic meniscus healing response and technical challenges associated with meniscus repair contribute to a high rate of repair failures and meniscectomies. Given this limited healing response, the development of biologically active adjuncts to meniscal repair may hold the key to improving meniscal repair success rates. This study demonstrates the development of a bone marrow (BM) adhesive that binds, stabilizes, and stimulates fusion at the interface of meniscus tissues. Hydrogels containing several chondroitin sulfate (CS) adhesive levels (30, 50, and 70 mg/mL) and BM levels (30%, 50%, and 70%) were formed to investigate the effects of these components on hydrogel mechanics, bovine meniscal fibrochondrocyte viability, proliferation, matrix production, and migration ability in vitro. The BM content positively and significantly affected fibrochondrocyte viability, proliferation, and migration, while the CS content positively and significantly affected adhesive strength (ranged from 60±17 kPa to 335±88 kPa) and matrix production. Selected material formulations were translated to a subcutaneous model of meniscal fusion using adhered bovine meniscus explants implanted in athymic rats and evaluated over a 3-month time course. Fusion of adhered meniscus occurred in only the material containing the highest BM content. The technology can serve to mechanically stabilize the tissue repair interface and stimulate tissue regeneration across the injury site.

PubMed Central

Schulz-Wendtland, Rüdiger; Jud, Sebastian M.; Fasching, Peter A.; Hartmann, Arndt; Radicke, Marcus; Rauh, Claudia; Uder, Michael; Wunderle, Marius; Gass, Paul; Langemann, Hanna; Beckmann, Matthias W.; Emons, Julius

2017-01-01

Aim The combination of different imaging modalities through the use of fusion devices promises significant diagnostic improvement for breast pathology. The aim of this study was to evaluate image quality and clinical feasibility of a prototype fusion device (fusion prototype) constructed from a standard tomosynthesis mammography unit and a standard 3D ultrasound probe using a new method of breast compression. Materials and Methods Imaging was performed on 5 mastectomy specimens from patients with confirmed DCIS or invasive carcinoma (BI-RADS ™ 6). For the preclinical fusion prototype an ABVS system ultrasound probe from an Acuson S2000 was integrated into a MAMMOMAT Inspiration (both Siemens Healthcare Ltd) and, with the aid of a newly developed compression plate, digital mammogram and automated 3D ultrasound images were obtained. Results The quality of digital mammogram images produced by the fusion prototype was comparable to those produced using conventional compression. The newly developed compression plate did not influence the applied x-ray dose. The method was not more labour intensive or time-consuming than conventional mammography. From the technical perspective, fusion of the two modalities was achievable. Conclusion In this study, using only a few mastectomy specimens, the fusion of an automated 3D ultrasound machine with a standard mammography unit delivered images of comparable quality to conventional mammography. The device allows simultaneous ultrasound – the second important imaging modality in complementary breast diagnostics – without increasing examination time or requiring additional staff. PMID:28713173

INTRODUCTION: Status report on fusion research

NASA Astrophysics Data System (ADS)

Burkart, Werner

2005-10-01

A major milestone on the path to fusion energy was reached in June 2005 on the occasion of the signing of the joint declaration of all parties to the ITER negotiations, agreeing on future arrangements and on the construction site at Cadarache in France. The International Atomic Energy Agency has been promoting fusion activities since the late 1950s; it took over the auspices of the ITER Conceptual Design Activities in 1988, and of the ITER Engineering and Design Activities in 1992. The Agency continues its support to Member States through the organization of consultancies, workshops and technical meetings, the most prominent being the series of International Fusion Energy Conferences (formerly called the International Conference on Plasma Physics and Controlled Nuclear Fusion Research). The meetings serve as a platform for experts from all Member States to have open discussions on their latest accomplishments as well as on their problems and eventual solutions. The papers presented at the meetings and conferences are routinely published, many being sent to the journal it Nuclear Fusion, co-published monthly by Institute of Physics Publishing, Bristol, UK. The journal's reputation is reflected in the fact that it is a world-renowned publication, and the International Fusion Research Council has used it for the publication of a Status Report on Controlled Thermonuclear Fusion in 1978 and 1990. This present report marks the conclusion of the preparatory phases of ITER activities. It provides background information on the progress of fusion research within the last 15 years. The International Fusion Research Council (IFRC), which initiated the report, was fully aware of the complexities of including all scientific results in just one paper, and so decided to provide an overview and extensive references for the interested reader who need not necessarily be a fusion specialist. Professor Predhiman K. Kaw, Chairman, prepared the report on behalf of the IFRC, reflecting members' personal views on the latest achievements in fusion research, including magnetic and inertial confinement scenarios. The report describes fusion fundamentals and progress in fusion science and technology, with ITER as a possible partner in the realization of self-sustainable burning plasma. The importance of the socio-economic aspects of energy production using fusion power plants is also covered. Noting that applications of plasma science are of broad interest to the Member States, the report addresses the topic of plasma physics to assist in understanding the achievements of better coatings, cheaper light sources, improved heat-resistant materials and other high-technology materials. Nuclear fusion energy production is intrinsically safe, but for ITER the full range of hazards will need to be addressed, including minimising radiation exposure, to accomplish the goal of a sustainable and environmentally acceptable production of energy. We anticipate that the role of the Agency will in future evolve from supporting scientific projects and fostering information exchange to the preparation of safety principles and guidelines for the operation of burning fusion plasmas with a Q > 1. Technical progress in inertial and magnetic confinement, as well as in alternative concepts, will lead to a further increase in international cooperation. New means of communication will be needed, utilizing the best resources of modern information technology to advance interest in fusion. However, today the basis of scientific progress is still through journal publications and, with this in mind, we trust that this report will find an interested readership. We acknowledge with thanks the support of the members of the IFRC as an advisory body to the Agency. Seven chairmen have presided over the IFRC since its first meeting in 1971 in Madison, USA, ensuring that the IAEA fusion efforts were based on the best professional advice possible, and that information on fusion developments has been widely and expertly disseminated. We further acknowledge the efforts of the Chairman of the IFRC and of all authors and experts who contributed to this report on the present status of fusion research.

Plasma-material Interactions in Current Tokamaks and their Implications for Next-step Fusion Reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Federici, G.; Skinner, C.H.; Brooks, J.N.

2001-01-10

The major increase in discharge duration and plasma energy in a next-step DT [deuterium-tritium] fusion reactor will give rise to important plasma-material effects that will critically influence its operation, safety, and performance. Erosion will increase to a scale of several centimeters from being barely measurable at a micron scale in today's tokamaks. Tritium co-deposited with carbon will strongly affect the operation of machines with carbon plasma-facing components. Controlling plasma wall interactions is critical to achieving high performance in present-day tokamaks and this is likely to continue to be the case in the approach to practical fusion reactors. Recognition of themore » important consequences of these phenomena has stimulated an internationally coordinated effort in the field of plasma-surface interactions supporting the Engineering Design Activities of the International Thermonuclear Experimental Reactor (ITER) project and significant progress has been made in better under standing these issues. This paper reviews the underlying physical processes and the existing experimental database of plasma-material interactions both in tokamaks and laboratory simulation facilities for conditions of direct relevance to next-step fusion reactors. Two main topical groups of interactions are considered: (i) erosion/redeposition from plasma sputtering and disruptions, including dust and flake generation, (ii) tritium retention and removal. The use of modeling tools to interpret the experimental results and make projections for conditions expected in future devices is explained. Outstanding technical issues and specific recommendations on potential R and D [Research and Development] avenues for their resolution are presented.« less

Magnetized Target Fusion Driven by Plasma Liners

NASA Technical Reports Server (NTRS)

Thio, Y. C. Francis; Kirkpatrick, Ronald C.; Knapp, Charles E.; Rodgers, Stephen L. (Technical Monitor)

2002-01-01

Magnetized target fusion is an emerging, relatively unexplored approach to fusion for electrical power and propulsion application. The physical principles of the concept are founded upon both inertial confinement fusion (ICF) and magnetic confinement fusion (MCF). It attempts to combine the favorable attributes of both these orthogonal approaches to fusion, but at the same time, avoiding the extreme technical challenges of both by exploiting a fusion regime intermediate between them. It uses a material liner to compress, heat and contain the fusion reacting plasma (the target plasma) mentally. By doing so, the fusion burn could be made to occur at plasma densities as high as six orders of magnitude higher than conventional MCF such as tokamak, thus leading to an approximately three orders of magnitude reduction in the plasma energy required for ignition. It also uses a transient magnetic field, compressed to extremely high intensity (100's T to 1000T) in the target plasma, to slow down the heat transport to the liner and to increase the energy deposition of charged-particle fusion products. This has several compounding beneficial effects. It leads to longer energy confinement time compared with conventional ICF without magnetized target, and thus permits the use of much lower plasma density to produce reasonable burn-up fraction. The compounding effects of lower plasma density and the magneto-insulation of the target lead to greatly reduced compressional heating power on the target. The increased energy deposition rate of charged-particle fusion products also helps to lower the energy threshold required for ignition and increasing the burn-up fraction. The reduction in ignition energy and the compressional power compound to lead to reduced system size, mass and R&D cost. It is a fusion approach that has an affordable R&D pathway, and appears attractive for propulsion application in the nearer term.

Condylar Joint Fusion and Stabilization (by Screws and Plates) in Nontraumatic Atlanto-Occipital Dislocation: Technical Report of 2 Cases.

PubMed

Chowdhury, Forhad H; Haque, Mohammod Raziul; Alam, Sarwar Murshed; Khaled Chowdhury, S M Noman; Khan, Shamsul Islam; Goel, Atul

2017-11-01

Nontraumatic spontaneous atlanto-occipital dislocation (AOD) is rare. In this report, we discuss the technical steps of condylar joint fusion and stabilization (by screws and plates) in nontraumatic AOD. To the best of our knowledge, it is the first report of such techniques. A young girl and a young man with progressive quadriparesis due to nontraumatic spontaneous atlanto-occipital dislocation were managed by microsurgical reduction, fusion, and stabilization of the joint by occipital condylar and C1 lateral mass screw and plate fixation after mobilization of vertebral artery. In both cases, condylar joints fixation and fusion were done successfully. Condylar joint stabilization and fusion may be a good or alternative option for AOD. Copyright © 2017 Elsevier Inc. All rights reserved.

[Carbon fiber-reinforced plastics as implant materials].

PubMed

Bader, R; Steinhauser, E; Rechl, H; Siebels, W; Mittelmeier, W; Gradinger, R

2003-01-01

Carbon fiber-reinforced plastics have been used clinically as an implant material for different applications for over 20 years.A review of technical basics of the composite materials (carbon fibers and matrix systems), fields of application,advantages (e.g., postoperative visualization without distortion in computed and magnetic resonance tomography), and disadvantages with use as an implant material is given. The question of the biocompatibility of carbon fiber-reinforced plastics is discussed on the basis of experimental and clinical studies. Selected implant systems made of carbon composite materials for treatments in orthopedic surgery such as joint replacement, tumor surgery, and spinal operations are presented and assessed. Present applications for carbon fiber reinforced plastics are seen in the field of spinal surgery, both as cages for interbody fusion and vertebral body replacement.

Conceptual design and issues of the laser inertial fusion test (LIFT) reactor—targets and chamber systems

NASA Astrophysics Data System (ADS)

Norimatsu, T.; Kozaki, Y.; Shiraga, H.; Fujita, H.; Okano, K.; Members of LIFT Design Team

2017-11-01

We present the conceptual design of an experimental laser fusion plant known as the laser inertial fusion test (LIFT) reactor. The conceptual design aims at technically connecting a single-shot experiment and a commercial power plant. The LIFT reactor is designed on a three-phase scheme, where each phase has specific goals and the dedicated chambers of each phase are driven by the same laser. Technical issues related to the chamber technology including radiation safety to repeat burst mode operation are discussed in this paper.

Damage resistant optics for a mega-joule solid-state laser

NASA Astrophysics Data System (ADS)

Campbell, J. H.; Rainer, F.; Kozlowski, M. R.; Wolfe, C. R.; Thomas, I.; Milanovich, F.

1990-12-01

Research on Inertial Confinement Fusion (ICF) has progressed rapidly in the past several years. As a consequence, LLNL is developing plans to upgrade the current 120 kJ solid state (Nd3+ phosphate glass) Nova laser to a 1.5 to 2 megajoule system with the goal of achieving fusion ignition. The design of the planned Nova Upgrade is briefly discussed. Because of recent improvements in the damage resistance of optical materials it is now technically and economically feasible to build a megajoule-class solid state laser. Specifically, the damage threshold of Nd(+3)-doped phosphate laser glass, multilayer dielectric coatings, and non-linear optical crystals (e.g., KDP) have been dramatically improved. These materials now meet the fluence requirements for a 1.5 to 2 MJ Nd(+3)-glass laser operating at 1054 and 351 nm and at a pulse length of 3 ns. The recent improvements in damage thresholds are reviewed; threshold data at both 1064 and 355 nm and the measured pulse length scaling are presented.

Damage resistant optics for a megajoule solid state laser

NASA Astrophysics Data System (ADS)

Campbell, Jack H.; Rainer, Frank; Kozlowski, Mark R.; Wolfe, C. Robert; Thomas, Ian M.; Milanovich, Fred P.

1991-06-01

Research on Inertial Confinement Fusion (ICF) has progressed rapidly in the past several years. As a consequence LLNL is developing plans to upgrade the current 120 kJ solid state (Nd3-phosphate glass) Nova laser to a 1 . 5 to 2 megajoule system with the goal of achieving fusion ignition. The design of the planned Nova Upgrade is briefly discussed. Because of recent improvements in the damage resistance of optical materials it is now technically and economically feasible to build a megajoule-class solid state laser. Specifically the damage threshold of Nd3- doped phosphate laser glass muliilayer dielectric coatings and non-linear optical crystals (e. g. KDP) have been dramatically improved. These materials now meet the fluence requirements for a 1. 5-2 MJ Nd3-glass laser operating at 1054 and 351 nm and at a pulse length of 3 ns. The recent improvements in damage thresholds are reviewed threshold data at both 1064 and 355 nm and the measured pulse length scaling are presented. 1.

A methodology for accident analysis of fusion breeder blankets and its application to helium-cooled lead–lithium blanket

DOE PAGES

Panayotov, Dobromir; Poitevin, Yves; Grief, Andrew; ...

2016-09-23

'Fusion for Energy' (F4E) is designing, developing, and implementing the European Helium-Cooled Lead-Lithium (HCLL) and Helium-Cooled Pebble-Bed (HCPB) Test Blanket Systems (TBSs) for ITER (Nuclear Facility INB-174). Safety demonstration is an essential element for the integration of these TBSs into ITER and accident analysis is one of its critical components. A systematic approach to accident analysis has been developed under the F4E contract on TBS safety analyses. F4E technical requirements, together with Amec Foster Wheeler and INL efforts, have resulted in a comprehensive methodology for fusion breeding blanket accident analysis that addresses the specificity of the breeding blanket designs, materials,more » and phenomena while remaining consistent with the approach already applied to ITER accident analyses. Furthermore, the methodology phases are illustrated in the paper by its application to the EU HCLL TBS using both MELCOR and RELAP5 codes.« less

Optical materials characterization final technical report february 1, 1978-september 30, 1978. Technical note

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feldman, A.; Horowitz, D.; Waxter, R.M.

1979-02-01

Data obtained as part of the Optical Materials Characterization Program are summarized in this report. Room temperature values of refractive index as a function of wavelength are presented for the following materials: commercially grown KCl, reactive atmosphere processed (RAP) KCl, KCl nominally doped with 1.5% KI, hot forged CaF2, fusion cast CaF2, CaF2 doped with Er (0.001% to 3% Er), SrF2, chemical vapor deposited (CVD) ZnSe (2 specimens), and ZnS (CVD, 2 specimens). Data for the thermo-optic constant (dn/dT) and the linear thermal expansion coefficient are given for the following materials over the temperature range -180 degrees C to 200more » degrees C: Al2O3, BaF2, CaF2, CdF2, KBr, KCl, LiF, MgF2, NaCl, NaF, SrF2, ZnS (CVD), and ZnSe (CVD). The piezo-optic constants of the following materials are presented: As2S3 glass, CaF2, BaF2, Ge, KCl, fused SiO2, SrF2, a chalcogenide glass (Ge 33%, As 12%, Se 55%) and ZnSe (CVD).« less

Fusion Power.

ERIC Educational Resources Information Center

Dingee, David A.

1979-01-01

Discusses the extraordinary potential, the technical difficulties, and the financial problems that are associated with research and development of fusion power plants as a major source of energy. (GA)

Failure study of helium-cooled tungsten divertor plasma-facing units tested at DEMO relevant steady-state heat loads

NASA Astrophysics Data System (ADS)

Ritz, G.; Hirai, T.; Norajitra, P.; Reiser, J.; Giniyatulin, R.; Makhankov, A.; Mazul, I.; Pintsuk, G.; Linke, J.

2009-12-01

Tungsten was selected as armor material for the helium-cooled divertor in future DEMO-type fusion reactors and fusion power plants. After realizing the design and testing of them under cyclic thermal loads of up to ~14 MW m-2, the tungsten divertor plasma-facing units were examined by metallography; they revealed failures such as cracks at the thermal loaded and as-machined surfaces, as well as degradation of the brazing layers. Furthermore, in order to optimize the machining processes, the quality of tungsten surfaces prepared by turning, milling and using a diamond cutting wheel were examined. This paper presents a metallographic examination of the tungsten plasma-facing units as well as technical studies and the characterization on machining of tungsten and alternative brazing joints.

Fusion Materials Research at Oak Ridge National Laboratory in Fiscal Year 2014

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiffen, Frederick W.; Noe, Susan P.; Snead, Lance Lewis

2014-10-01

The realization of fusion energy is a formidable challenge with significant achievements resulting from close integration of the plasma physics and applied technology disciplines. Presently, the most significant technological challenge for the near-term experiments such as ITER, and next generation fusion power systems, is the inability of current materials and components to withstand the harsh fusion nuclear environment. The overarching goal of the ORNL fusion materials program is to provide the applied materials science support and understanding to underpin the ongoing DOE Office of Science fusion energy program while developing materials for fusion power systems. In doing so the programmore » continues to be integrated both with the larger U.S. and international fusion materials communities, and with the international fusion design and technology communities.« less

Fusion or confusion: knowledge or nonsense?

NASA Astrophysics Data System (ADS)

Rothman, Peter L.; Denton, Richard V.

1991-08-01

The terms 'data fusion,' 'sensor fusion,' multi-sensor integration,' and 'multi-source integration' have been used widely in the technical literature to refer to a variety of techniques, technologies, systems, and applications which employ and/or combine data derived from multiple information sources. Applications of data fusion range from real-time fusion of sensor information for the navigation of mobile robots to the off-line fusion of both human and technical strategic intelligence data. The Department of Defense Critical Technologies Plan lists data fusion in the highest priority group of critical technologies, but just what is data fusion? The DoD Critical Technologies Plan states that data fusion involves 'the acquisition, integration, filtering, correlation, and synthesis of useful data from diverse sources for the purposes of situation/environment assessment, planning, detecting, verifying, diagnosing problems, aiding tactical and strategic decisions, and improving system performance and utility.' More simply states, sensor fusion refers to the combination of data from multiple sources to provide enhanced information quality and availability over that which is available from any individual source alone. This paper presents a survey of the state-of-the- art in data fusion technologies, system components, and applications. A set of characteristics which can be utilized to classify data fusion systems is presented. Additionally, a unifying mathematical and conceptual framework within which to understand and organize fusion technologies is described. A discussion of often overlooked issues in the development of sensor fusion systems is also presented.

Fusion materials: Technical evaluation of the technology of vandium alloys for use as blanket structural materials in fusion power systems

NASA Astrophysics Data System (ADS)

1993-08-01

The Committee's evaluation of vanadium alloys as a structural material for fusion reactors was constrained by limited data and time. The design of the International Thermonuclear Experimental Reactor is still in the concept stage, so meaningful design requirements were not available. The data on the effect of environment and irradiation on vanadium alloys were sparse, and interpolation of these data were made to select the V-5Cr-5Ti alloy. With an aggressive, fully funded program it is possible to qualify a vanadium alloy as the principal structural material for the ITER blanket in the available 5 to 8-year window. However, the data base for V-5Cr-5Ti is limited and will require an extensive development and test program. Because of the chemical reactivity of vanadium the alloy will be less tolerant of system failures, accidents, and off-normal events than most other candidate blanket structural materials and will require more careful handling during fabrication of hardware. Because of the cost of the material more stringent requirements on processes, and minimal historical working experience, it will cost an order of magnitude to qualify a vanadium alloy for ITER blanket structures than other candidate materials. The use of vanadium is difficult and uncertain; therefore, other options should be explored more thoroughly before a final selection of vanadium is confirmed. The Committee views the risk as being too high to rely solely on vanadium alloys. In viewing the state and nature of the design of the ITER blanket as presented to the Committee, it is obvious that there is a need to move toward integrating fabrication, welding, and materials engineers into the ITER design team. If the vanadium alloy option is to be pursued, a large program needs to be started immediately. The commitment of funding and other resources needs to be firm and consistent with a realistic program plan.

Condition Monitoring of Large-Scale Facilities

NASA Technical Reports Server (NTRS)

Hall, David L.

1999-01-01

This document provides a summary of the research conducted for the NASA Ames Research Center under grant NAG2-1182 (Condition-Based Monitoring of Large-Scale Facilities). The information includes copies of view graphs presented at NASA Ames in the final Workshop (held during December of 1998), as well as a copy of a technical report provided to the COTR (Dr. Anne Patterson-Hine) subsequent to the workshop. The material describes the experimental design, collection of data, and analysis results associated with monitoring the health of large-scale facilities. In addition to this material, a copy of the Pennsylvania State University Applied Research Laboratory data fusion visual programming tool kit was also provided to NASA Ames researchers.

Rapid Method for Sodium Hydroxide Fusion of Concrete and ...

EPA Pesticide Factsheets

Technical Fact Sheet Analysis Purpose: Qualitative analysis Technique: Alpha spectrometry Method Developed for: Americium-241, plutonium-238, plutonium-239, radium-226, strontium-90, uranium-234, uranium-235 and uranium-238 in concrete and brick samples Method Selected for: SAM lists this method for qualitative analysis of americium-241, plutonium-238, plutonium-239, radium-226, strontium-90, uranium-234, uranium-235 and uranium-238 in concrete or brick building materials. Summary of subject analytical method which will be posted to the SAM website to allow access to the method.

Information Fusion for Situational Awareness

DTIC Science & Technology

2003-01-01

UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP021704 TITLE: Information Fusion for Situational Awareness DISTRIBUTION...component part numbers comprise the compilation report: ADP021634 thru ADP021736 UNCLASSIFIED Information Fusion for Situational Awareness Dr. John...Situation Assessment, or level 2 be applied to address Situational Awareness - the processing, the knowledge of objects, their goal of this paper

50 years of fusion research

NASA Astrophysics Data System (ADS)

Meade, Dale

2010-01-01

Fusion energy research began in the early 1950s as scientists worked to harness the awesome power of the atom for peaceful purposes. There was early optimism for a quick solution for fusion energy as there had been for fission. However, this was soon tempered by reality as the difficulty of producing and confining fusion fuel at temperatures of 100 million °C in the laboratory was appreciated. Fusion research has followed two main paths—inertial confinement fusion and magnetic confinement fusion. Over the past 50 years, there has been remarkable progress with both approaches, and now each has a solid technical foundation that has led to the construction of major facilities that are aimed at demonstrating fusion energy producing plasmas.

Unenhanced Cone Beam Computed Tomography and Fusion Imaging in Direct Percutaneous Sac Injection for Treatment of Type II Endoleak: Technical Note

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carrafiello, Gianpaolo, E-mail: gcarraf@gmail.com; Ierardi, Anna Maria; Radaelli, Alessandro

AimTo evaluate safety, feasibility, technical success, and clinical success of direct percutaneous sac injection (DPSI) for the treatment of type II endoleaks (T2EL) using anatomical landmarks on cone beam computed tomography (CBCT) and fusion imaging (FI).Materials and MethodsEight patients with T2EL were treated with DPSI using CBCT as imaging guidance. Anatomical landmarks on unenhanced CBCT were used for referencing T2EL location in the first five patients, while FI between unenhanced CBCT and pre-procedural computed tomography angiography (CTA) was used in the remaining three patients. Embolization was performed with thrombin, glue, and ethylene–vinyl alcohol copolymer. Technical and clinical success, iodinated contrastmore » utilization, procedural time, fluoroscopy time, and mean radiation dose were registered.ResultsDPSI was technically successful in all patients: the needle was correctly positioned at the first attempt in six patients, while in two of the first five patients the needle was repositioned once. Neither minor nor major complications were registered. Average procedural time was 45 min and the average administered iodinated contrast was 13 ml. Mean radiation dose of the procedure was 60.43 Gy cm{sup 2} and mean fluoroscopy time was 18 min. Clinical success was achieved in all patients (mean follow-up of 36 months): no sign of T2EL was reported in seven patients until last CT follow-up, while it persisted in one patient with stability of sac diameter.ConclusionsDPSI using unenhanced CBCT and FI is feasible and provides the interventional radiologist with an accurate and safe alternative to endovascular treatment with limited iodinated contrast utilization.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Panayotov, Dobromir; Poitevin, Yves; Grief, Andrew

'Fusion for Energy' (F4E) is designing, developing, and implementing the European Helium-Cooled Lead-Lithium (HCLL) and Helium-Cooled Pebble-Bed (HCPB) Test Blanket Systems (TBSs) for ITER (Nuclear Facility INB-174). Safety demonstration is an essential element for the integration of these TBSs into ITER and accident analysis is one of its critical components. A systematic approach to accident analysis has been developed under the F4E contract on TBS safety analyses. F4E technical requirements, together with Amec Foster Wheeler and INL efforts, have resulted in a comprehensive methodology for fusion breeding blanket accident analysis that addresses the specificity of the breeding blanket designs, materials,more » and phenomena while remaining consistent with the approach already applied to ITER accident analyses. Furthermore, the methodology phases are illustrated in the paper by its application to the EU HCLL TBS using both MELCOR and RELAP5 codes.« less

Funding for the 2ND IAEA technical meeting on fusion data processing, validation and analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greenwald, Martin

The International Atomic Energy Agency (IAEA) will organize the second Technical Meeting on Fusion Da Processing, Validation and Analysis from 30 May to 02 June, 2017, in Cambridge, MA USA. The meeting w be hosted by the MIT Plasma Science and Fusion Center (PSFC). The objective of the meeting is to provide a platform where a set of topics relevant to fusion data processing, validation and analysis are discussed with the view of extrapolation needs to next step fusion devices such as ITER. The validation and analysis of experimental data obtained from diagnostics used to characterize fusion plasmas are crucialmore » for a knowledge based understanding of the physical processes governing the dynamics of these plasmas. The meeting will aim at fostering, in particular, discussions of research and development results that set out or underline trends observed in the current major fusion confinement devices. General information on the IAEA, including its mission and organization, can be found at the IAEA websit Uncertainty quantification (UQ) Model selection, validation, and verification (V&V) Probability theory and statistical analysis Inverse problems & equilibrium reconstru ction Integrated data analysis Real time data analysis Machine learning Signal/image proc essing & pattern recognition Experimental design and synthetic diagnostics Data management« less

Technical reference on socket heat fusion joining of polyethylene gas pipes. Volume 2. Topical Report, September 1989-September 1990

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pimputkar, S.M.; McCoy, J.K.; Stets, J.A.

1991-03-01

The integrity of a pipeline system is determined by its weakest links which may be the joints. Heat fusion is the most common method for joining gas distribution polyethylene (PE) piping. There are procedural, thermal, and mechanical aspects of making fusion joints. Acceptable procedural aspects, such as heater calibration and cleanliness, can be assured by rigorous training and certification of the operators. Thermal and mechanical aspects consist of specifying joining conditions such as the heater temperature, heating time, and joining pressure. In the absence of procedural errors, the strength of a fusion joint should depend on the pipe material, pipemore » dimensions, and the thermal and mechanical joining conditions. Socket heat fusion was studied both experimentally and analytically to determine how the strength of the joint varied with the conditions under which it was made. The standard tensile impact test was modified to test socket fusion joint samples in shear. The developed shear impact energy test data were found to be reliable measures of strength if the setup conditions were meticulously identical. A parameter, termed the socket joining parameter, was found to characterize the joining conditions. It is a strong function of melt volume at the end of the heating phase, and, physically, it is polyethylene transported parallel to the axis during insertion. The results for three resins are presented in the form of three nomographs. The nomographs may be used to select the required heater temperature or the heating time, for a given ambient temperature and a PE resin, to ensure a structurally sound socket heat fusion joint.« less

Thermonuclear land of plenty

NASA Astrophysics Data System (ADS)

Gasior, P.

2014-11-01

Since the process of energy production in the stars has been identified as the thermonuclear fusion, this mechanism has been proclaimed as a future, extremely modern, reliable and safe for sustaining energetic needs of the humankind. However, the idea itself was rather straightforward and the first attempts to harness thermonuclear reactions have been taken yet in 40s of the twentieth century, it quickly appeared that physical and technical problems of domesticating exotic high temperature medium known as plasma are far from being trivial. Though technical developments as lasers, superconductors or advanced semiconductor electronics and computers gave significant contribution for the development of the thermonuclear fusion reactors, for a very long time their efficient performance was out of reach of technology. Years of the scientific progress brought the conclusions that for the development of the thermonuclear power plants an enormous interdisciplinary effort is needed in many fields of science covering not only plasma physics but also material research, superconductors, lasers, advanced diagnostic systems (e.g. spectroscopy, interferometry, scattering techniques, etc.) with huge amounts of data to be processed, cryogenics, measurement-control systems, automatics, robotics, nanotechnology, etc. Due to the sophistication of the problems with plasma control and plasma material interactions only such a combination of the research effort can give a positive output which can assure the energy needs of our civilization. In this paper the problems of thermonuclear technology are briefly outlined and it is shown why this domain can be a broad field for the experts dealing with electronics, optoelectronics, programming and numerical simulations, who at first glance can have nothing common with the plasma or nuclear physics.

Review of the magnetic fusion program by the 1986 ERAB Fusion Panel

NASA Astrophysics Data System (ADS)

Davidson, Ronald C.

1987-09-01

The 1986 ERAB Fusion Panel finds that fusion energy continues to be an attractive energy source with great potential for the future, and that the magnetic fusion program continues to make substantial technical progress. In addition, fusion research advances plasma physics, a sophisticated and useful branch of applied science, as well as technologies important to industry and defense. These factors fully justify the substantial expenditures by the Department of Energy in fusion research and development (R&D). The Panel endorses the overall program direction, strategy, and plans, and recognizes the importance and timeliness of proceeding with a burning plasma experiment, such as the proposed Compact Ignition Tokamak (CIT) experiment.

Final Technical Report for "Nuclear Technologies for Near Term Fusion Devices"

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilson, Paul P.H.; Sawan, Mohamed E.; Davis, Andrew

Over approximately 18 years, this project evolved to focus on a number of related topics, all tied to the nuclear analysis of fusion energy systems. For the earliest years, the University of Wisconsin (UW)’s effort was in support of the Advanced Power Extraction (APEX) study to investigate high power density first wall and blanket systems. A variety of design concepts were studied before this study gave way to a design effort for a US Test Blanket Module (TBM) to be installed in ITER. Simultaneous to this TBM project, nuclear analysis supported the conceptual design of a number of fusion nuclearmore » science facilities that might fill a role in the path to fusion energy. Beginning in approximately 2005, this project added a component focused on the development of novel radiation transport software capability in support of the above nuclear analysis needs. Specifically, a clear need was identified to support neutron and photon transport on the complex geometries associated with Computer-Aided Design (CAD). Following the initial development of the Direct Accelerated Geoemtry Monte Carlo (DAGMC) capability, additional features were added, including unstructured mesh tallies and multi-physics analysis such as the Rigorous 2-Step (R2S) methodology for Shutdown Dose Rate (SDR) prediction. Throughout the project, there were also smaller tasks in support of the fusion materials community and for the testing of changes to the nuclear data that is fundamental to this kind of nuclear analysis.« less

Clinical Application of Prognostic Gene Expression Signature in Fusion Gene-Negative Rhabdomyosarcoma: A Report from the Children's Oncology Group.

PubMed

Hingorani, Pooja; Missiaglia, Edoardo; Shipley, Janet; Anderson, James R; Triche, Timothy J; Delorenzi, Mauro; Gastier-Foster, Julie; Wing, Michele; Hawkins, Douglas S; Skapek, Stephen X

2015-10-15

Pediatric rhabdomyosarcoma (RMS) has two common histologic subtypes: embryonal (ERMS) and alveolar (ARMS). PAX-FOXO1 fusion gene status is a more reliable prognostic marker than alveolar histology, whereas fusion gene-negative (FN) ARMS patients are clinically similar to ERMS patients. A five-gene expression signature (MG5) previously identified two diverse risk groups within the fusion gene-negative RMS (FN-RMS) patients, but this has not been independently validated. The goal of this study was to test whether expression of the MG5 metagene, measured using a technical platform that can be applied to routine pathology material, would correlate with outcome in a new cohort of patients with FN-RMS. Cases were taken from the Children's Oncology Group (COG) D9803 study of children with intermediate-risk RMS, and gene expression profiling for the MG5 genes was performed using the nCounter assay. The MG5 score was correlated with clinical and pathologic characteristics as well as overall and event-free survival. MG5 standardized score showed no significant association with any of the available clinicopathologic variables. The MG5 signature score showed a significant correlation with overall (N = 57; HR, 7.3; 95% CI, 1.9-27.0; P = 0.003) and failure-free survival (N = 57; HR, 6.1; 95% CI, 1.9-19.7; P = 0.002). This represents the first, validated molecular prognostic signature for children with FN-RMS who otherwise have intermediate-risk disease. The capacity to measure the expression of a small number of genes in routine pathology material and apply a simple mathematical formula to calculate the MG5 metagene score provides a clear path toward better risk stratification in future prospective clinical trials. ©2015 American Association for Cancer Research.

Processing and Fusion of Electro-Optic Information

DTIC Science & Technology

2001-04-01

UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP010886 TITLE: Processing and Fusion of Electro - Optic Information...component part numbers comprise the compilation report: ADP010865 thru ADP010894 UNCLASSIFIED 21-1 Processing and Fusion of Electro - Optic Information I...additional electro - optic (EO) sensor model within OOPSDG. It describes TM IT TT T T T performance estimates found prior to producing the New Ne- New

Towards a programme of testing and qualification for structural and plasma-facing materials in ‘fusion neutron’ environments

NASA Astrophysics Data System (ADS)

Stork, D.; Heidinger, R.; Muroga, T.; Zinkle, S. J.; Moeslang, A.; Porton, M.; Boutard, J.-L.; Gonzalez, S.; Ibarra, A.

2017-09-01

Materials damage by 14.1MeV neutrons from deuterium-tritium (D-T) fusion reactions can only be characterised definitively by subjecting a relevant configuration of test materials to high-intensity ‘fusion-neutron spectrum sources’, i.e. those simulating closely D-T fusion-neutron spectra. This provides major challenges to programmes to design and construct a demonstration fusion reactor prior to having a large-scale, high-intensity source of such neutrons. In this paper, we discuss the different aspects related to these ‘relevant configuration’ tests, including: • generic issues in materials qualification/validation, comparing safety requirements against those of investment protection; • lessons learned from the fission programme, enabling a reduced fusion materials testing programme; • the use and limitations of presently available possible irradiation sources to optimise a fusion neutron testing program including fission-neutron irradiation of isotopically and chemically tailored steels, ion damage by high-energy helium ions and self-ion beams, or irradiation studies with neutron sources of non-fusion spectra; and • the different potential sources of simulated fusion neutron spectra and the choice using stripping reactions from deuterium-beam ions incident on light-element targets.

Thermal management in inertial fusion energy slab amplifiers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sutton, S.B.; Albrecht, G.F.

As the technology associated with the development of solid-state drivers for inertial fusion energy (IFE) has evolved, increased emphasis has been placed on the development of an efficient approach for managing the waste heat generated in the laser media. This paper addresses the technical issues associated with the gas cooling of large aperture slabs, where the laser beam propagates through the cooling fluid. It is shown that the major consequence of proper thermal management is the introduction of simple wedge, or beam steering, into the system. Achieving proper thermal management requires careful consideration of the geometry, cooling fluid characteristics, coolingmore » flow characteristics, as well as the thermal/mechanical/optical characteristics of the laser media. Particularly important are the effects of cooling rate variation and turbulent scattering on the system optical performance. Helium is shown to have an overwhelming advantage with respect to turbulent scattering losses. To mitigate cooling rate variations, the authors introduce the concept of flow conditioning. Finally, optical path length variations across the aperture are calculated. A comparison of two laser materials (S-FAP and YAG) shows the benefit of a nearly a-thermal material on optical variations in the system.« less

Local bone graft harvesting and volumes in posterolateral lumbar fusion: a technical report.

PubMed

Carragee, Eugene J; Comer, Garet C; Smith, Micah W

2011-06-01

In lumbar surgery, local bone graft is often harvested and used in posterolateral fusion procedures. The volume of local bone graft available for posterolateral fusion has not been determined in North American patients. Some authors have described this as minimal, but others have suggested the volume was sufficient to be reliably used as a stand-alone bone graft substitute for single-level fusion. To describe the technique used and determine the volume of local bone graft available in a cohort of patients undergoing single-level primary posterolateral fusion by the authors harvesting technique. Technical description and cohort report. Consecutive patients undergoing lumbar posterolateral fusion with or without instrumentation for degenerative processes. Local bone graft volume. Consecutive patients undergoing lumbar posterolateral fusion with or without instrumentation for degenerative processes of were studied. Local bone graft was harvested by a standard method in each patient and the volume measured by a standard procedure. Twenty-five patients were studied, and of these 11 (44%) had a previous decompression. The mean volume of local bone graft harvested was measured to be 25 cc (range, 12-36 cc). Local bone graft was augmented by iliac crest bone in six of 25 patients (24%) if the posterolateral fusion bed was not well packed with local bone alone. There was a trend to greater local bone graft volumes in men and in patients without previous decompression. Large volumes of local bone can be harvested during posterolateral lumbar fusion surgery. Even in patients with previous decompression the volume harvested is similar to that reported harvested from the posterior iliac crest for single-level fusion. Copyright © 2011 Elsevier Inc. All rights reserved.

International strategy for fusion materials development

NASA Astrophysics Data System (ADS)

Ehrlich, Karl; Bloom, E. E.; Kondo, T.

2000-12-01

In this paper, the results of an IEA-Workshop on Strategy and Planning of Fusion Materials Research and Development (R&D), held in October 1998 in Risø Denmark are summarised and further developed. Essential performance targets for materials to be used in first wall/breeding blanket components have been defined for the major materials groups under discussion: ferritic-martensitic steels, vanadium alloys and ceramic composites of the SiC/SiC-type. R&D strategies are proposed for their further development and qualification as reactor-relevant materials. The important role of existing irradiation facilities (mainly fission reactors) for materials testing within the next decade is described, and the limits for the transfer of results from such simulation experiments to fusion-relevant conditions are addressed. The importance of a fusion-relevant high-intensity neutron source for the development of structural as well as breeding and special purpose materials is elaborated and the reasons for the selection of an accelerator-driven D-Li-neutron source - the International Fusion Materials Irradiation Facility (IFMIF) - as an appropriate test bed are explained. Finally the necessity to execute the materials programme for fusion in close international collaboration, presently promoted by the International Energy Agency, IEA is emphasised.

An Investigation for Ground State Features of Some Structural Fusion Materials

NASA Astrophysics Data System (ADS)

Aytekin, H.; Tel, E.; Baldik, R.; Aydin, A.

2011-02-01

Environmental concerns associated with fossil fuels are creating increased interest in alternative non-fossil energy sources. Nuclear fusion can be one of the most attractive sources of energy from the viewpoint of safety and minimal environmental impact. When considered in all energy systems, the requirements for performance of structural materials in a fusion reactor first wall, blanket or diverter, are arguably more demanding or difficult than for other energy system. The development of fusion materials for the safety of fusion power systems and understanding nuclear properties is important. In this paper, ground state properties for some structural fusion materials as 27Al, 51V, 52Cr, 55Mn, and 56Fe are investigated using Skyrme-Hartree-Fock method. The obtained results have been discussed and compared with the available experimental data.

Technology Area Roadmap for In Space Propulsion Technologies

NASA Technical Reports Server (NTRS)

Johnson, Les; Meyer, Mike; Coote, David; Goebel, Dan; Palaszewski, Bryan; White, Sonny

2010-01-01

This slide presentation reviews the technology area (TA) roadmap to develop propulsion technologies that will be used to enable further exploration of the solar system, and beyond. It is hoped that development of the technologies within this TA will result in technical solutions that will improve thrust levels, specific impulse, power, specific mass, volume, system mass, system complexity, operational complexity, commonality with other spacecraft systems, manufacturability and durability. Some of the propulsion technologies that are reviewed include: chemical and non-chemical propulsion, and advanced propulsion (i.e., those with a Technology Readiness level of less than 3). Examples of these advanced technologies include: Beamed Energy, Electric Sail, Fusion, High Energy Density Materials, Antimatter, Advanced Fission and Breakthrough propulsion technologies. Timeframes for development of some of these propulsion technologies are reviewed, and top technical challenges are reviewed. This roadmap describes a portfolio of in-space propulsion technologies that can meet future space science and exploration needs.

Progress in understanding the neuronal SNARE function and its regulation.

PubMed

Yoon, T-Y; Shin, Y-K

2009-02-01

Vesicle budding and fusion underlies many essential biochemical deliveries in eukaryotic cells, and its core fusion machinery is thought to be built on one protein family named soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE). Recent technical advances based on site-directed fluorescence labelling and nano-scale detection down to the single-molecule level rapidly unveiled the protein and the lipid intermediates along the fusion pathway as well as the molecular actions of fusion effectors. Here we summarize these new exciting findings in context with a new mechanistic model that reconciles two existing fusion models: the proteinaceous pore model and the hemifusion model. Further, we attempt to locate the points of action for the fusion effectors along the fusion pathway and to delineate the energetic interplay between the SNARE complexes and the fusion effectors.

Early Career. Harnessing nanotechnology for fusion plasma-material interface research in an in-situ particle-surface interaction facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allain, Jean Paul

2014-08-08

This project consisted of fundamental and applied research of advanced in-situ particle-beam interactions with surfaces/interfaces to discover novel materials able to tolerate intense conditions at the plasma-material interface (PMI) in future fusion burning plasma devices. The project established a novel facility that is capable of not only characterizing new fusion nanomaterials but, more importantly probing and manipulating materials at the nanoscale while performing subsequent single-effect in-situ testing of their performance under simulated environments in fusion PMI.

Heating Efficiency of Beat Wave Excitation in a Density Gradient,

DTIC Science & Technology

1988-02-01

and Technology, January 1988. PPG-1124 񓟣 Research Highlights in The Pisces Program," R.V. Conn, et al, January 1988. PPG-1125 "Magnetic Fusion ... Energy , vol. 5. Technical Assessement of Critical Issues in the Steady State Operation of Fusion Confinement Devices," D. M. Goebel, Assessment Chairman

Development of advanced high heat flux and plasma-facing materials

NASA Astrophysics Data System (ADS)

Linsmeier, Ch.; Rieth, M.; Aktaa, J.; Chikada, T.; Hoffmann, A.; Hoffmann, J.; Houben, A.; Kurishita, H.; Jin, X.; Li, M.; Litnovsky, A.; Matsuo, S.; von Müller, A.; Nikolic, V.; Palacios, T.; Pippan, R.; Qu, D.; Reiser, J.; Riesch, J.; Shikama, T.; Stieglitz, R.; Weber, T.; Wurster, S.; You, J.-H.; Zhou, Z.

2017-09-01

Plasma-facing materials and components in a fusion reactor are the interface between the plasma and the material part. The operational conditions in this environment are probably the most challenging parameters for any material: high power loads and large particle and neutron fluxes are simultaneously impinging at their surfaces. To realize fusion in a tokamak or stellarator reactor, given the proven geometries and technological solutions, requires an improvement of the thermo-mechanical capabilities of currently available materials. In its first part this article describes the requirements and needs for new, advanced materials for the plasma-facing components. Starting points are capabilities and limitations of tungsten-based alloys and structurally stabilized materials. Furthermore, material requirements from the fusion-specific loading scenarios of a divertor in a water-cooled configuration are described, defining directions for the material development. Finally, safety requirements for a fusion reactor with its specific accident scenarios and their potential environmental impact lead to the definition of inherently passive materials, avoiding release of radioactive material through intrinsic material properties. The second part of this article demonstrates current material development lines answering the fusion-specific requirements for high heat flux materials. New composite materials, in particular fiber-reinforced and laminated structures, as well as mechanically alloyed tungsten materials, allow the extension of the thermo-mechanical operation space towards regions of extreme steady-state and transient loads. Self-passivating tungsten alloys, demonstrating favorable tungsten-like plasma-wall interaction behavior under normal operation conditions, are an intrinsic solution to otherwise catastrophic consequences of loss-of-coolant and air ingress events in a fusion reactor. Permeation barrier layers avoid the escape of tritium into structural and cooling materials, thereby minimizing the release of tritium under normal operation conditions. Finally, solutions for the unique bonding requirements of dissimilar material used in a fusion reactor are demonstrated by describing the current status and prospects of functionally graded materials.

Promoting Pre-college Science Education

NASA Astrophysics Data System (ADS)

Lee, R. L.

1999-11-01

The Fusion Education Program, with support from DOE, continues to promote pre-college science education for students and teachers using multiple approaches. An important part of our program is direct scientist-student interaction. Our ``Scientist in a Classroom'' program allows students to interact with scientists and engage in plasma science activities in the students' classroom. More than 1000 students from 11 schools have participated in this exciting program. Also, this year more than 800 students and teachers have visited the DIII--D facility and interacted with scientists to cover a broad range of technical and educational issues. Teacher-scientist interaction is imperative in professional development and each year more than 100 teachers attend workshops produced by the fusion education team. We also participate in unique learning opportunities. Members of the team, in collaboration with the San Diego County Office of Education, held a pioneering Internet-based Physics Olympiad for American and Siberian students. Our teamwork with educators helps shape material that is grade appropriate, relevant, and stimulates thinking in educators and students.

PREFACE: The fifth International Conference on Inertial Fusion Sciences and Applications (IFSA2007)

NASA Astrophysics Data System (ADS)

Azechi, Hiroshi; Hammel, Bruce; Gauthier, Jean-Claude

2008-06-01

The Fifth International Conference on Inertial Fusion Sciences and Applications (IFSA 2007) was held on 9-14 September 2007 at Kobe International Conference Center in Kobe, Japan. The host organizations for this conference were Osaka University and the Institute of Laser Engineering (ILE) at Osaka University; and co-organized by the Institute Lasers and Plasmas (ILP) in France, the Commissariatá l'Energie Atomique (CEA), Lawrence Livermore National Laboratory (LLNL), National Institute for Fusion Science (NIFS) in Japan, and Kansai Photon Science Institute (KPSI), Japan Atomic Energy Agency (JAEA). The conference objective was to review the state of the art of research in inertial fusion sciences and applications since the last conference held in Biarritz, France, in 2005. 470 abstracts were accepted, and 448 persons from 18 countries attended the conference. These Proceedings contain 287 of the papers presented at IFSA 2007. This collection of papers represents the manuscripts submitted to and passing the peer review process. The program was organized with some specific features: The reviews of influential programs appeared both at the very beginning and at the very end of the Conference to attract attendance throughout the Conference. Each poster session had the same time period as a single oral session, thereby avoiding overlap with oral talks. The everyday program was structured to be as similar as possible so the attendees could easily recognize the program. With a goal of achieving inertial fusion ignition and burn propagation in the laboratory, researchers presented the exciting advances in both traditional hot spot ignition and fast ignition approach, including status report of USA's National Ignition Facility (NIF), French Laser Magajoule (LMJ), Japanese Fast Ignition Realization Experiment (FIREX), and European High Power laser Energy Research (HiPER). A particular emphasis of the meeting was that the `physics of inertial fusion' category was dominated by fast-ignition and related ultra-intense laser interaction. Progress in direct drive over the past few years resulted in the achievement of high-density cryogenic implosions at OMEGA. Continuous progresses in hohlraum physics gave confidence in the achievement of ignition at NIF and LMJ. Advances in Z-pinch included double-hohlraum irradiation symmetry and the PW laser beam for the Z-facility. Progress of laser material development for IFE driver was a very interesting topic of inertial fusion energy drivers, including KrF and DPSSL lasers and particle beams. Of special interest, a future session was focused on strategy of inertial fusion energy development. Laboratory tours were held in the middle of the Conference. The Laser for Fusion EXperiments (LFEX), a new high-energy petawatt laser at ILE, was one of the key attractions of IFSA 2007. 83 participants toured LFEX and GEKKO XII lasers, and 35 joined a tour of KPSA-JAEA. In parallel to the tour, the `Symposium on Academics-Industries Cooperation for Applications of High-Power Lasers' was held with more than 90 participants mostly from the industrial community. These Proceedings start with special chapters on the keynote and focus speeches and the Teller lectures. The keynotes and focus give an overview of progress in inertial fusion in Asia, North America, and Europe. The Teller lectures show the contributions of this year's two winners: Brian Thomas of AWE, UK and Kunioki Mima of ILE. The remainder of the Proceedings is divided into three parts. Part A covers the physics of inertial fusion; Part B covers laser, particle beams, and fusion technology including IFE reactors and target fabrication; and Part C covers science and technology applications such as laboratory astrophysics, laser particle acceleration, x-ray and EUV sources, and new applications of intense lasers. These parts are further divided into chapters covering specific areas of science or technology. Within each chapter the talks relevant to that subject are gathered. The IFSA International Organizing Committee and Scientific Advisory Board appreciate the efforts of inertial fusion researchers worldwide in making IFSA 2007 an extremely successful conference. The proceedings were published with the support of Dr Y Sakawa, Dr H Homma, Ms S Karasuyama, Ms M Odagiri, and Ms I Kobatake. Kunioki Mima Co-chair Hiroshi Azechi Technical Program Committee Co-chair John Lindl Co-chair Bruce Hammel Technical Program Committee Co-chair Christine Labaune Co-chair Jean-Claude Gauthier Technical Program Committee Co-chair

Plasma-wall interaction data needs critical to a Burning Core Experiment (BCX)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1985-11-01

The Division of Development and Technology has sponsored a four day US-Japan workshop ''Plasma-Wall Interaction Data Needs Critical to a Burning Core Experiment (BCX)'', held at Sandia National Laboratories, Livermore, California on June 24 to 27, 1985. The workshop, which brought together fifty scientists and engineers from the United States, Japan, Germany, and Canada, considered the plasma-material interaction and high heat flux (PMI/HHF) issues for the next generation of magnetic fusion energy devices, the Burning Core Experiment (BCX). Materials options were ranked, and a strategy for future PMI/HHF research was formulated. The foundation for international collaboration and coordination of thismore » research was also established. This volume contains the last three of the five technical sessions. The first of the three is on plasma materials interaction issues, the second is on research facilities and the third is from smaller working group meetings on graphite, beryllium, advanced materials and future collaborations.« less

Double differential light charged particle emission cross sections for some structural fusion materials

NASA Astrophysics Data System (ADS)

Sarpün, Ismail Hakki; n, Abdullah Aydı; Tel, Eyyup

2017-09-01

In fusion reactors, neutron induced radioactivity strongly depends on the irradiated material. So, a proper selection of structural materials will have been limited the radioactive inventory in a fusion reactor. First-wall and blanket components have high radioactivity concentration due to being the most flux-exposed structures. The main objective of fusion structural material research is the development and selection of materials for reactor components with good thermo-mechanical and physical properties, coupled with low-activation characteristics. Double differential light charged particle emission cross section, which is a fundamental data to determine nuclear heating and material damages in structural fusion material research, for some elements target nuclei have been calculated by the TALYS 1.8 nuclear reaction code at 14-15 MeV neutron incident energy and compared with available experimental data in EXFOR library. Direct, compound and pre-equilibrium reaction contribution have been theoretically calculated and dominant contribution have been determined for each emission of proton, deuteron and alpha particle.

[Fusion implants of carbon fiber reinforced plastic].

PubMed

Früh, H J; Liebetrau, A; Bertagnoli, R

2002-05-01

Carbon fiber reinforced plastics (CFRP) are used in the medical field when high mechanical strength, innovative design, and radiolucency (see spinal fusion implants) are needed. During the manufacturing process of the material CFRP carbon fibers are embedded into a resin matrix. This resin material could be thermoset (e.g., epoxy resin EPN/DDS) or thermoplastic (e.g., PEAK). CFRP is biocompatible, radiolucent, and has higher mechanical capabilities compared to other implant materials. This publication demonstrates the manufacturing process of fusion implants made of a thermoset matrix system using a fiber winding process. The material has been used clinically since 1994 for fusion implants of the cervical and lumbar spine. The results of the fusion systems CORNERSTONE-SR C (cervical) and UNION (lumbar) showed no implant-related complications. New implant systems made of this CFRP material are under investigation and are presented.

A Preliminary Report on the CO2 Laser for Lumbar Fusion: Safety, Efficacy and Technical Considerations.

PubMed

Villavicencio, Alan T; Burneikiene, Sigita; Babuska, Jason M; Nelson, Ewell L; Mason, Alexander; Rajpal, Sharad

2015-04-01

The purpose of this study was to evaluate potential technical advantages of the CO2 laser technology in mini-open transforaminal lumbar interbody fusion (TLIF) surgeries and report our preliminary clinical data on the safety and clinical outcomes. There is currently no literature discussing the recently redeveloped CO2 laser technology application for lumbar fusion. Safety and clinical outcomes were compared between two groups: 24 patients that underwent CO2 laser-assisted one-level TLIF surgeries and 30 patients that underwent standard one-level TLIF surgeries without the laser. There were no neural thermal injuries or other intraoperative laser-related complications encountered in this cohort of patients. At a mean follow-up of 17.4 months, significantly reduced lower back pain scores (P=0.013) were reported in the laser-assisted patient group compared to a standard fusion patient group. Lower extremity radicular pain intensity scores were similar in both groups. Laser-assisted TLIF surgeries showed a tendency (P = 0.07) of shorter operative times that was not statistically significant. Based on this preliminary clinical report, the safety of the CO2 laser device for lumbar fusion surgeries was assessed. There were no neural thermal injuries or other intraoperative laser-related complications encountered in this cohort of patients. Further investigation of CO2 laser-assisted lumbar fusion procedures is warranted in order to evaluate its effect on clinical outcomes.

Towards reconstitution of membrane fusion mediated by SNAREs and other synaptic proteins

PubMed Central

Brunger, Axel T.; Cipriano, Daniel J.; Diao, Jiajie

2015-01-01

Abstract Proteoliposomes have been widely used for in vitro studies of membrane fusion mediated by synaptic proteins. Initially, such studies were made with large unsynchronized ensembles of vesicles. Such ensemble assays limited the insights into the SNARE-mediated fusion mechanism that could be obtained from them. Single particle microscopy experiments can alleviate many of these limitations but they pose significant technical challenges. Here we summarize various approaches that have enabled studies of fusion mediated by SNAREs and other synaptic proteins at a single-particle level. Currently available methods are described and their advantages and limitations are discussed. PMID:25788028

Fusion for Space Propulsion

NASA Technical Reports Server (NTRS)

Thio, Y. C. Francis; Schafer, Charles (Technical Monitor)

2001-01-01

There is little doubt that humans will attempt to explore and develop the solar system in this century. A large amount of energy will be required for accomplishing this. The need for fusion propulsion is discussed. For a propulsion system, there are three important thermodynamical attributes: (1) The absolute amount of energy available, (2) the propellant exhaust velocity, and (3) the jet power per unit mass of the propulsion system (specific power). For human exploration and development of the solar system, propellant exhaust velocity in excess of 100 km/s and specific power in excess of 10 kW/kg are required. Chemical combustion can produce exhaust velocity up to about 5 km/s. Nuclear fission processes typically result in producing energy in the form of heat that needs to be manipulated at temperatures limited by materials to about 2,800 K. Using the energy to heat a hydrogen propellant increases the exhaust velocity by only a factor of about two. Alternatively the energy can be converted into electricity which is then used to accelerate particles to high exhaust velocity. The necessary power conversion and conditioning equipment, however, increases the mass of the propulsion system for the same jet power by more than two orders of magnitude over chemical system, thus greatly limits the thrust-to-weight ratio attainable. The principal advantage of the fission process is that its development is relatively mature and is available right now. If fusion can be developed, fusion appears to have the best of all worlds in terms of propulsion - it can provide the absolute amount, the propellant exhaust velocity, and the high specific jet power. An intermediate step towards pure fusion propulsion is a bimodal system in which a fission reactor is used to provide some of the energy to drive a fusion propulsion unit. The technical issues related to fusion for space propulsion are discussed. The technical priorities for developing and applying fusion for propulsion are somewhat different from those for terrestrial electrical power generation. Thus fusion schemes that are initially attractive for electrical power generation might not necessarily be attractive also for propulsion and vice versa, though the underlying fusion science and engineering enjoy much overlap. Parallel efforts to develop these qualitatively differently fusion schemes for the two applications could benefit greatly from each other due to the synergy in the underlying physics and engineering. Pulsed approaches to fusion have not been explored to the same degree as steady-state or long-pulse approaches to fusion in the fusion power research program. The concerns early on were several. One was that the pulsed power components might not have the service lifetimes meeting the requirements of a practical power generating plant. Another was that, for many pulsed fusion schemes, it was not clear whether the destruction of hardware per pulse could be minimized or eliminated or recycled to such an extent as to make economical electrical power generation feasible, Significant development of the underlying pulsed power component technologies have occurred in the last two decades because of defense and other energy requirements. The state of development of the pulsed power technologies are sufficiently advanced now to make it compelling to visit or re-visit pulsed fusion approaches for application to propulsion where the cost of energy is not so demanding a factor as in the case of terrestrial power application. For propulsion application, the overall mass of the fusion system is the critical factor. Producing fusion reactions require extreme states of matter. Conceptually, these extreme states of matter are more readily realizable in the pulsed states, at least within appropriate bounds, than in the steady states. Significant saving in system mass may result in such systems. Magnetic fields are effective in confining plasma energy, whereas inertial compression is an effective way of heating and containing the plasma. Intensive research in developing magnetic energy containment and inertial plasma compression are being pursued in distinctively different fusion experiments in the terrestrial fusion power program. Fusion schemes that attempt to combine the favorable attributes of these two aspects into one single integrated fusion scheme appear to have benefits that are worth exploring for propulsion application.

Recent Accomplishments and Future Directions in US Fusion Safety & Environmental Program

DOE Office of Scientific and Technical Information (OSTI.GOV)

David A. Petti; Brad J. Merrill; Phillip Sharpe

2006-07-01

The US fusion program has long recognized that the safety and environmental (S&E) potential of fusion can be attained by prudent materials selection, judicious design choices, and integration of safety requirements into the design of the facility. To achieve this goal, S&E research is focused on understanding the behavior of the largest sources of radioactive and hazardous materials in a fusion facility, understanding how energy sources in a fusion facility could mobilize those materials, developing integrated state of the art S&E computer codes and risk tools for safety assessment, and evaluating S&E issues associated with current fusion designs. In thismore » paper, recent accomplishments are reviewed and future directions outlined.« less

Fusion for Space Propulsion and Plasma Liner Driven MTF

NASA Technical Reports Server (NTRS)

Thio, Y.C. Francis; Rodgers, Stephen L. (Technical Monitor)

2001-01-01

The need for fusion propulsion for interplanetary flights is discussed. For a propulsion system, there are three important system attributes: (1) The absolute amount of energy available, (2) the propellant exhaust velocity, and (3) the jet power per unit mass of the propulsion system (specific power). For human exploration and development of the solar system, propellant exhaust velocity in excess of 100 km/s and specific power in excess of 10 kW/kg are required. Chemical combustion cannot meet the requirement in propellant exhaust velocity. Nuclear fission processes typically result in producing energy in the form of heat that needs to be manipulated at temperatures limited by materials to about 2,800 K. Using the energy to heat a low atomic weight propellant cannot overcome the problem. Alternatively the energy can be converted into electricity which is then used to accelerate particles to high exhaust velocity. The necessary power conversion and conditioning equipment, however, increases the mass of the propulsion system for the same jet power by more than two orders of magnitude over chemical system, thus greatly limits the thrust-to-weight ratio attainable. If fusion can be developed, fusion appears to have the best of all worlds in terms of propulsion - it can provide the absolute amount, the propellant exhaust velocity, and the high specific jet power. An intermediate step towards pure fusion propulsion is a bimodal system in which a fission reactor is used to provide some of the energy to drive a fusion propulsion unit. The technical issues related to fusion for space propulsion are discussed. There are similarities as well as differences at the system level between applying fusion to propulsion and to terrestrial electrical power generation. The differences potentially provide a wider window of opportunities for applying fusion to propulsion. For example, pulsed approaches to fusion may be attractive for the propulsion application. This is particularly so in the light of significant development of the enabling pulsed power component technologies that have occurred in the last two decades because of defense and other energy requirements. The extreme states of matter required to produce fusion reactions may be more readily realizable in the pulsed states with less system mass than in steady states. Significant saving in system mass may result in pulsed fusion systems using plasmas in the appropriate density regimes. Magnetized target fusion, which attempts to combine the favorable attributes of magnetic confinement and inertial compression-containment into one single integrated fusion scheme, appears to have benefits that are worth exploring for propulsion application.

[A technical modification of the use of Dwyer's equipment].

PubMed

Carlioz, H; Damsin, J P

1991-01-01

Dwyer's technique for correction and anterior fusion of the spine was improved by using lockers at the level of each screw. So, like with the Zielke's technic this procedure allowed a global progressive and controllable correction and a real derotation of the spine.

On the radiation damage characterization of candidate first wall materials in a fusion reactor using various molten salts

NASA Astrophysics Data System (ADS)

Übeyli, Mustafa

2006-12-01

Evaluating radiation damage characteristics of structural materials considered to be used in fusion reactors is very crucial. In fusion reactors, the highest material damage occurs in the first wall because it will be exposed to the highest neutron, gamma ray and charged particle currents produced in the fusion chamber. This damage reduces the lifetime of the first wall material and leads to frequent replacement of this material during the reactor operation period. In order to decrease operational cost of a fusion reactor, lifetime of the first wall material should be extended to reactor's lifetime. Using a protective flowing liquid wall between the plasma and first wall can decrease the radiation damage on first wall and extend its lifetime to the reactor's lifetime. In this study, radiation damage characterization of various low activation materials used as first wall material in a magnetic fusion reactor blanket using a liquid wall was made. Various coolants (Flibe, Flibe + 4% mol ThF 4, Flibe + 8% mol ThF 4, Li 20Sn 80) were used to investigate their effect on the radiation damage of first wall materials. Calculations were carried out by using the code Scale4.3 to solve Boltzmann neutron transport equation. Numerical results brought out that the ferritic steel with Flibe based coolants showed the best performance with respect to radiation damage.

Molecular imaging of malignant tumor metabolism: whole-body image fusion of DWI/CT vs. PET/CT.

PubMed

Reiner, Caecilia S; Fischer, Michael A; Hany, Thomas; Stolzmann, Paul; Nanz, Daniel; Donati, Olivio F; Weishaupt, Dominik; von Schulthess, Gustav K; Scheffel, Hans

2011-08-01

To prospectively investigate the technical feasibility and performance of image fusion for whole-body diffusion-weighted imaging (wbDWI) and computed tomography (CT) to detect metastases using hybrid positron emission tomography/computed tomography (PET/CT) as reference standard. Fifty-two patients (60 ± 14 years; 18 women) with different malignant tumor disease examined by PET/CT for clinical reasons consented to undergo additional wbDWI at 1.5 Tesla. WbDWI was performed using a diffusion-weighted single-shot echo-planar imaging during free breathing. Images at b = 0 s/mm(2) and b = 700 s/mm(2) were acquired and apparent diffusion coefficient (ADC) maps were generated. Image fusion of wbDWI and CT (from PET/CT scan) was performed yielding for wbDWI/CT fused image data. One radiologist rated the success of image fusion and diagnostic image quality. The presence or absence of metastases on wbDWI/CT fused images was evaluated together with the separate wbDWI and CT images by two different, independent radiologists blinded to results from PET/CT. Detection rate and positive predictive values for diagnosing metastases was calculated. PET/CT examinations were used as reference standard. PET/CT identified 305 malignant lesions in 39 of 52 (75%) patients. WbDWI/CT image fusion was technically successful and yielded diagnostic image quality in 73% and 92% of patients, respectively. Interobserver agreement for the evaluation of wbDWI/CT images was κ = 0.78. WbDWI/CT identified 270 metastases in 43 of 52 (83%) patients. Overall detection rate and positive predictive value of wbDWI/CT was 89% (95% CI, 0.85-0.92) and 94% (95% CI, 0.92-0.97), respectively. WbDWI/CT image fusion is technically feasible in a clinical setting and allows the diagnostic assessment of metastatic tumor disease detecting nine of 10 lesions as compared with PET/CT. Copyright © 2011 AUR. Published by Elsevier Inc. All rights reserved.

Improved Bone Graft Method for Upper Cervical Surgery with Posterior Approach: Technical Description and Report of 52 Cases.

PubMed

Wang, Yong-Li; Wang, Xiang-Yang

2018-06-01

We sought to report a minimum 12 months' follow-up results of our improved bone graft method for upper cervical surgery with the posterior approach. Among 52 consecutive cases, odontoid nonunion occurred in 33 patients, atlantoaxial instability in 11 patients, and occipitocervical deformity in 8 patients who underwent posterior C1-C2 transarticular screw/screw-rod internal fixation (41 cases) and occipitocervical fusion (11 cases) with the improved bone graft technique. Each surgical procedure was performed by the same senior spine surgeon. We took lateral cervical standing roentgenograms before surgery and immediately after surgery. Then we conducted craniocerebral computed tomography examination with reconstruction at 3, 6, 12, and 24 months and annually thereafter. The postoperative follow-up times are about 12-38 months. All cases showed satisfactory screw fixation by radiographic examination, and there were no postoperative neurologic complications. One case had postoperative retropharyngeal infection after the transoral release and posterior reduction by pedicle screw instrumentation. All patients got solid fusions, and no pseudarthrosis occurred. All cases had solid fusions at the 3-month follow-up. Good bone graft bed, enough bone graft material, solid local fixation, and effective bone graft method are prerequisites for a successful bone graft. By analyzing postoperative follow-up in the consecutive cases in this study, our bone graft method describing a new bone graft structure is a reliable posterior fusion technique. It is worth considering, and further research is needed. Copyright © 2018. Published by Elsevier Inc.

IAEA activities on atomic, molecular and plasma-material interaction data for fusion

NASA Astrophysics Data System (ADS)

Braams, Bastiaan J.; Chung, Hyun-Kyung

2013-09-01

The IAEA Atomic and Molecular Data Unit (http://www-amdis.iaea.org/) aims to provide internationally evaluated and recommended data for atomic, molecular and plasma-material interaction (A+M+PMI) processes in fusion research. The Unit organizes technical meetings and coordinates an A+M Data Centre Network (DCN) and a Code Centre Network (CCN). In addition the Unit organizes Coordinated Research Projects (CRPs), for which the objectives are mixed between development of new data and evaluation and recommendation of existing data. In the area of A+M data we are placing new emphasis in our meeting schedule on data evaluation and especially on uncertainties in calculated cross section data and the propagation of uncertainties through structure data and fundamental cross sections to effective rate coefficients. Following a recent meeting of the CCN it is intended to use electron scattering on Be, Ne and N2 as exemplars for study of uncertainties and uncertainty propagation in calculated data; this will be discussed further at the presentation. Please see http://www-amdis.iaea.org/CRP/ for more on our active and planned CRPs, which are concerned with atomic processes in core and edge plasma and with plasma interaction with beryllium-based surfaces and with irradiated tungsten.

Polarized fusion, its implications, and plans for a proof-of-principle experiment at the DIII-D tokamak

NASA Astrophysics Data System (ADS)

Sandorfi, A. M.; Deur, A.; Lowry, M. M.; Wei, X.; Pace, D.; Eidietis, N.; Hyatt, A.; Jackson, G. L.; Lanctot, M.; Smith, S.; St-John, H.; Miller, G. W.; Zheng, X.; Baylor, L. R.

2015-10-01

The cross section for the primary fusion reaction in a tokamak, D+t --> α +n, would increase by a factor of 1.5 if the fuels were spin polarized parallel to the local field, rather than randomly oriented. Simulations show further gains in reaction rate would accompany this increase in large-scale machines such as ITER, due to increased alpha heating. The potential realization of such benefits rests on the crucial question of the survival of spin polarization for periods comparable to the energy containment time. Despite encouraging calculations, technical challenges in preparing and handling polarized materials have prevented any direct tests. Advances in three areas - polarized material technologies developed for nuclear and particle physics as well as medical imaging, polymer pellets developed for Inertial Confinement, and cryogenic injection guns developed for fueling tokamaks - have matured to the point where a direct in situ measurement is possible using the mirror reaction, D+3He --> α +p. Designs and simulations of a proof-of-principle experiment at the DIII-D tokamak in San Diego will be discussed. Work carried out under US DOE Contract DE-AC05-06OR23177 supporting Jefferson Lab and General Atomics Internal R&D funding.

An Overview of INEL Fusion Safety R&D Facilities

NASA Astrophysics Data System (ADS)

McCarthy, K. A.; Smolik, G. R.; Anderl, R. A.; Carmack, W. J.; Longhurst, G. R.

1997-06-01

The Fusion Safety Program at the Idaho National Engineering Laboratory has the lead for fusion safety work in the United States. Over the years, we have developed several experimental facilities to provide data for fusion reactor safety analyses. We now have four major experimental facilities that provide data for use in safety assessments. The Steam-Reactivity Measurement System measures hydrogen generation rates and tritium mobilization rates in high-temperature (up to 1200°C) fusion relevant materials exposed to steam. The Volatilization of Activation Product Oxides Reactor Facility provides information on mobilization and transport and chemical reactivity of fusion relevant materials at high temperature (up to 1200°C) in an oxidizing environment (air or steam). The Fusion Aerosol Source Test Facility is a scaled-up version of VAPOR. The ion-implanta-tion/thermal-desorption system is dedicated to research into processes and phenomena associated with the interaction of hydrogen isotopes with fusion materials. In this paper we describe the capabilities of these facilities.

Added Value of Contrast-Enhanced Ultrasound on Biopsies of Focal Hepatic Lesions Invisible on Fusion Imaging Guidance.

PubMed

Kang, Tae Wook; Lee, Min Woo; Song, Kyoung Doo; Kim, Mimi; Kim, Seung Soo; Kim, Seong Hyun; Ha, Sang Yun

2017-01-01

To assess whether contrast-enhanced ultrasonography (CEUS) with Sonazoid can improve the lesion conspicuity and feasibility of percutaneous biopsies for focal hepatic lesions invisible on fusion imaging of real-time ultrasonography (US) with computed tomography/magnetic resonance images, and evaluate its impact on clinical decision making. The Institutional Review Board approved this retrospective study. Between June 2013 and January 2015, 711 US-guided percutaneous biopsies were performed for focal hepatic lesions. Biopsies were performed using CEUS for guidance if lesions were invisible on fusion imaging. We retrospectively evaluated the number of target lesions initially invisible on fusion imaging that became visible after applying CEUS, using a 4-point scale. Technical success rates of biopsies were evaluated based on histopathological results. In addition, the occurrence of changes in clinical decision making was assessed. Among 711 patients, 16 patients (2.3%) were included in the study. The median size of target lesions was 1.1 cm (range, 0.5-1.9 cm) in pre-procedural imaging. After CEUS, 15 of 16 (93.8%) focal hepatic lesions were visualized. The conspicuity score was significantly increased after adding CEUS, as compared to that on fusion imaging (p < 0.001). The technical success rate of biopsy was 87.6% (14/16). After biopsy, there were changes in clinical decision making for 11 of 16 patients (68.8%). The addition of CEUS could improve the conspicuity of focal hepatic lesions invisible on fusion imaging. This dual guidance using CEUS and fusion imaging may affect patient management via changes in clinical decision-making.

Plasma confinement theory and transport simulation. Technical progress report, May 1, 1991--April 30, 1992

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ross, D.W.

The objectives are: (1) to advance the transport studies of tokamaks, including development and maintenance of the Magnetic Fusion Energy Database, and (2) to provide theoretical interpretation, modeling and equilibrium and stability studies for TEXT-Upgrade. Recent reports, publications, and conference presentations of the Fusion Research Center are listed.

Sagittal imbalance treated with L5 pedicle subtraction osteotomy with short lumbar fusion from L4 to sacrum using four screws into L4 for enhanced fixation two additional vertebral screws: a technical note.

PubMed

Wangdi, Kuenzang; Otsuki, Bungo; Fujibayashi, Shunsuke; Tanida, Shimei; Masamoto, Kazutaka; Matsuda, Shuichi

2018-02-07

To report on suggested technique with four screws in a single vertebra (two pedicle screws and two direct vertebral body screws) for enhanced fixation with just one level cranially to a pedicle subtraction osteotomy (PSO). A 60-year-old woman underwent L4/5 fusion surgery for degenerative spondylolisthesis. Two years later, she was unable to stand upright even for a short time because of lumbar kyphosis caused by subsidence of the fusion cage and of Baastrup syndrome in the upper lumbar spine [sagittal vertical axis (SVA) of 114 mm, pelvic incidence of 75°, and lumbar lordosis (LL) of 41°]. She underwent short-segment fusion from L4 to the sacrum with L5 pedicle subtraction osteotomy. We reinforced the construct with two vertebral screws at L4 in addition to the conventional L4 pedicle screws. After the surgery, her sagittal parameters were improved (SVA, 36 mm; LL, 54°). Two years after the corrective surgery, she maintained a low sagittal vertical axis though high residual pelvic tilt indicated that the patient was still compensating for residual sagittal misalignment. PSO surgery for sagittal imbalance usually requires a long fusion at least two levels above and below the osteotomy site to achieve adequate stability and better global alignment. However, longer fixation may decrease the patients' quality of life and cause a proximal junctional failure. Our novel technique may shorten the fixation area after osteotomy surgery. These slides can be retrieved under Electronic Supplementary Material.

System and method for producing metallic iron nodules

DOEpatents

Bleifuss, Rodney L [Grand Rapids, MN; Englund, David J [Bovey, MN; Iwasaki, Iwao [Grand Rapids, MN; Lindgren, Andrew J [Grand Rapids, MN; Kiesel, Richard F [Hibbing, MN

2011-09-20

A method for producing metallic iron nodules by assembling a shielding entry system to introduce coarse carbonaceous material greater than 6 mesh in to the furnace atmosphere at location(s) where the temperature of the furnace atmosphere adjacent at least partially reduced reducible iron bearing material is between about 2200 and 2650.degree. F. (1200 and 1450.degree. C.), the shielding entry system adapted to inhibit emission of infrared radiation from the furnace atmosphere and seal the furnace atmosphere from exterior atmosphere while introducing coarse carbonaceous material greater than 6 mesh into the furnace to be distributed over the at least partially reduced reducible iron bearing material, and heating the covered at least partially reduced reducible iron bearing material in a fusion atmosphere to assist in fusion and inhibit reoxidation of the reduced material during fusion to assist in fusion and inhibit reoxidation of the reduced material in forming metallic iron nodules.

Advanced low-activation materials. Fibre-reinforced ceramic composites

NASA Astrophysics Data System (ADS)

Fenici, P.; Scholz, H. W.

1994-09-01

A serious safety and environmental concern for thermonuclear fusion reactor development regards the induced radioactivity of the first wall and structural components. The use of low-activation materials (LAM) in a demonstration reactor would reduce considerably its potential risk and facilitate its maintenance. Moreover, decommissioning and waste management including disposal or even recycling of structural materials would be simplified. Ceramic fibre-reinforced SiC materials offer highly appreciable low activation characteristics in combination with good thermomechanical properties. This class of materials is now under experimental investigation for structural application in future fusion reactors. An overview on the recent results is given, covering coolant leak rates, thermophysical properties, compatibility with tritium breeder materials, irradiation effects, and LAM-consistent purity. SiC/SiC materials present characteristics likely to be optimised in order to meet the fusion application challenge. The scope is to put into practice the enormous potential of inherent safety with fusion energy.

Palaeontological evidence of membrane relationship in step-by-step membrane fusion

PubMed Central

WANG, XIN; LIU, WENZHE; DU, KAIHE

2011-01-01

Studies on membrane fusion in living cells indicate that initiation of membrane fusion is a transient and hard to capture process. Despite previous research, membrane behaviour at this point is still poorly understood. Recent palaeobotanical research has revealed snapshots of membrane fusion in a 15-million-year-old fossil pinaceous cone. To reveal the membrane behaviour during the fusion, we conducted more observations on the same fossil material. Several discernible steps of membrane fusion have been fixed naturally and observed in the fossil material. This observation provides transmission electron microscope (TEM) images of the transient intermediate stage and clearly shows the relationship between membranes. Observing such a transient phenomenon in fossil material implies that the fixing was most likely accomplished quickly by a natural process. The mechanism behind this phenomenon is clearly worthy of further enquiry. PMID:21190428

The challenge of developing structural materials for fusion power systems

NASA Astrophysics Data System (ADS)

Bloom, Everett E.

1998-10-01

Nuclear fusion can be one of the most attractive sources of energy from the viewpoint of safety and minimal environmental impact. Central in the goal of designing a safe, environmentally benign, and economically competitive fusion power system is the requirement for high performance, low activation materials. The general performance requirements for such materials have been defined and it is clear that materials developed for other applications (e.g. aerospace, nuclear fission, fossil energy systems) will not fully meet the needs of fusion. Advanced materials, with composition and microstructure tailored to yield properties that will satisfy the specific requirements of fusion must be developed. The international fusion programs have made significant progress towards this goal. Compositional requirements for low activation lead to a focus of development efforts on silicon carbide composites, vanadium alloys, and advanced martensitic steels as candidate structural material systems. Control of impurities will be critically important in actually achieving low activation but this appears possible. Neutron irradiation produces significant changes in the mechanical and physical properties of each of these material systems raising feasibility questions and design limitations. A focus of the research and development effort is to understand these effects, and through the development of specific compositions and microstructures, produce materials with improved and adequate performance. Other areas of research that are synergistic with the development of radiation resistant materials include fabrication, joining technology, chemical compatibility with coolants and tritium breeders and specific questions relating to the unique characteristics of a given material (e.g. coatings to reduce gas permeation in SiC composites) or design concept (e.g. electrical insulator coatings for liquid metal concepts).

The emissivities of liquid metals at their fusion temperatures.

NASA Technical Reports Server (NTRS)

Bonnell, D. W.; Treverton, J. A.; Valerga, A. J.; Margrave , J. L.

1972-01-01

The emissivities for several transition metals and various other metals and compounds in the liquid state at their fusion temperatures have been determined in this laboratory. The technique used involves electromagnetic levitation-induction heating of the materials in an inert atmosphere. The brightness temperature of the liquid phase of the material is measured as the material is heated through fusion. Given a reliable value of the fusion temperature, which is available for most pure substances, one may readily calculate an emissivity for the liquid phase at the fusion temperature. Even in cases where melting points are poorly known, the brightness temperatures are unique parameters, independent of the temperature scale and measured for a chemically defined system at a fixed point.

Fusion Science Education Outreach

NASA Astrophysics Data System (ADS)

Danielson, C. A.; DIII-D Education Group

1996-11-01

This presentation will focus on education outreach activities at General Atomics that have been expanded to include the general population on science education with a focus on fusion energy. Outreach materials are distributed upon request both nationally and internationally. These materials include a notebook containing copies of DIII--D tour panels, fusion poster, new fusion energy video, new fusion energy brochure, and the electromagnetic spectrum curriculum. The 1996 Fusion Forum (held in the House Caucus Room) included a student/ teacher lunch with Energy Secretary Hazel O'Leary and a private visit to the Forum exhibits. The continuing partnership with Kearny High School includes lectures, job shadowing, internship, equipment donations and an award-winning electric car-racing program. Development of distribution by CD of the existing interactive fusion energy kiosk and a virtual reality tour of the DIII--D facility are underway. The DIII--D fusion education WWW site includes e-mail addresses to ``Ask the Wizard,'' and/or receive GA's outreach materials. Steve Rodecker, a local science teacher, aided by DIII--D fusion staff, won his second Tapestry Award; he also was named the ``1995 National Science Teacher of the Year'' and will be present to share his experiences with the DIII--D educational outreach program.

Fusion power: a challenge for materials science.

PubMed

Duffy, D M

2010-07-28

The selection and design of materials that will withstand the extreme conditions of a fusion power plant has been described as one of the greatest materials science challenges in history. The high particle flux, high thermal load, thermal mechanical stress and the production of transmutation elements combine to produce a uniquely hostile environment. In this paper, the materials favoured for the diverse roles in a fusion power plant are discussed, along with the experimental and modelling techniques that are used to advance the understanding of radiation damage in materials. Areas where further research is necessary are highlighted.

Data fusion algorithm for rapid multi-mode dust concentration measurement system based on MEMS

NASA Astrophysics Data System (ADS)

Liao, Maohao; Lou, Wenzhong; Wang, Jinkui; Zhang, Yan

2018-03-01

As single measurement method cannot fully meet the technical requirements of dust concentration measurement, the multi-mode detection method is put forward, as well as the new requirements for data processing. This paper presents a new dust concentration measurement system which contains MEMS ultrasonic sensor and MEMS capacitance sensor, and presents a new data fusion algorithm for this multi-mode dust concentration measurement system. After analyzing the relation between the data of the composite measurement method, the data fusion algorithm based on Kalman filtering is established, which effectively improve the measurement accuracy, and ultimately forms a rapid data fusion model of dust concentration measurement. Test results show that the data fusion algorithm is able to realize the rapid and exact concentration detection.

Fusion power for space propulsion.

NASA Technical Reports Server (NTRS)

Roth, R.; Rayle, W.; Reinmann, J.

1972-01-01

Principles of operation, interplanetary orbit-to-orbit mission capabilities, technical problems, and environmental safeguards are examined for thermonuclear fusion propulsion systems. Two systems examined include (1) a fusion-electric concept in which kinetic energy of charged particles from the plasma is converted into electric power (for accelerating the propellant in an electrostatic thrustor) by the van de Graaf generator principle and (2) the direct fusion rocket in which energetic plasma lost from the reactor has a suitable amount of added propellant to obtain the optimum exhaust velocity. The deuterium-tritium and the deuterium/helium-3 reactions are considered as suitable candidates, and attention is given to problems of cryogenic refrigeration systems, magnet shielding, and high-energy particle extraction and guidance.

Painful lumbosacral melorheostosis treated by fusion.

PubMed

Robertson, Peter A; Don, Angus S; Miller, Mary V

2003-06-15

A case report of low back pain associated with a diagnosis of melorheostosis of the lumbosacral spine. To describe a rare presentation of melorheostosis and subsequent successful surgical treatment. Melorheostosis is a rare condition and spinal pain has not been described in association with the condition. A patient with disabling low back pain and suspected melorheostosis of the lumbosacral spine responded favorably to diagnostic facet joint blocks. Treatment was lumbosacral fusion and biopsy of the abnormal bone. The densely sclerotic bone presented technical difficulties requiring modification of surgical technique. Dramatic pain and disability reduction occurred following lumbosacral fusion. Histologic examination was consistent with melorheostosis. Melorheostosis rarely causes severe low back pain that can respond favorably to fusion surgery.

Enhancing wear resistance of working bodies of grinder through lining crushed material

NASA Astrophysics Data System (ADS)

Romanovich, A. A.; Annenko, D. M.; Romanovich, M. A.; Apukhtina, I. V.

2018-03-01

The article presents the analysis of directions of increasing wear resistance of working surfaces of rolls. A technical solution developed at the level of the invention is proposed, which is simple to implement in production conditions and which makes it possible to protect the roll surface from heavy wear due to surfacing of wear-resistant mesh material, cells of which are filling with grinding material in the process of work. Retaining them enables one to protect the roll surface from wear. The paper dwells on conditions of pressing materials in cells of eccentric rolls on the working surface with a grid of rectangular shape. The paper presents an equation for calculation of the cell dimension that provides the lining of the working surface by a mill material with respect to its properties. The article presents results of comparative studies on the grinding process of a press roller grinder (PRG) between rolls with and without a fusion-bonded mesh. It is clarified that the lining of rolls working surface slightly reduces the quality of the grinding, since the material thickness in the cell is small and has a finely divided and compacted structure with high strength.

Report Summarizing the Effort Required to Initiate Welding of Irradiated Materials within the Welding Cubicle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frederick, Greg; Sutton, Benjamin J.; Tatman, Jonathan K.

The advanced welding facility within a hot cell at the Radiochemical Engineering Development Center of Oak Ridge National Laboratory (ORNL), which has been jointly funded by the U.S. Department of Energy (DOE), Office of Nuclear Energy, Light Water Reactor Sustainability Program and the Electric Power Research Institute, Long Term Operations Program and the Welding and Repair Technology Center, is in the final phase of development. Research and development activities in this facility will involve direct testing of advanced welding technologies on irradiated materials in order to address the primary technical challenge of helium induced cracking that can arise when conventionalmore » fusion welding techniques are utilized on neutron irradiated stainless steels and nickel-base alloys. This report details the effort that has been required since the beginning of fiscal year 2017 to initiate welding research and development activities on irradiated materials within the hot cell cubicle, which houses welding sub-systems that include laser beam welding (LBW) and friction stir welding (FSW) and provides material containment within the hot cell.« less

Extraforaminal Lumbar Interbody Fusion at the L5-S1 Level: Technical Considerations and Feasibility.

PubMed

Kurzbuch, Arthur Robert; Kaech, Denis; Baranowski, Pawel; Baranowska, Alicja; Recoules-Arche, Didier

2017-09-01

Background  Extraforaminal lumbar interbody fusion (ELIF) surgery is a muscle-sparing approach that allows the treatment of various degenerative spinal diseases. It is technical challenging to perform the ELIF approach at the L5-S1 level because the sacral ala obstructs the view of the intervertebral disk space. Methods  We reported earlier on the ELIF technique in which the intervertebral disk is targeted at an angle of 45 degrees relative to the midline. In this article we describe the technical process we developed to overcome the anatomic relation between the sacral ala and the intervertebral disk space L5-S1 that hinders the ELIF approach at this level. We then report in a retrospective analysis on the short-term clinical and radiologic outcome of 100 consecutive patients with degenerative L5-S1 pathologies who underwent ELIF surgery. Results  The L5-S1 ELIF approach could be realized in all patients. The short-term clinical outcome was evaluated 5 months after surgery: 92% of the patients were satisfied with their postoperative result; 8% had a poor result. Overall, 17% of the patients presented light radicular or low back pain not influencing their daily activity, and 82% of the patients working before surgery returned to work 3 to 7 months after surgery. The radiologic outcome was documented by computed tomography at 5 months after surgery and showed fusion in 99% of the patients. Lumbar magnetic resonance imaging performed in 5 patients at 6 months after surgery revealed the integrity of the paraspinal muscles. Conclusions  ELIF surgery at the L5-S1 level is technically feasible for various degenerative spinal diseases. Analysis of the clinical and radiologic data in a consecutive retrospective cohort of patients who underwent this surgical procedure showed a good short-term clinical outcome and fusion rate. Georg Thieme Verlag KG Stuttgart · New York.

Advantages and challenges of dissimilar materials in automotive lightweight construction

NASA Astrophysics Data System (ADS)

Weberpals, Jan-Philipp; Schmidt, Philipp A.; Böhm, Daniel; Müller, Steffen

2015-03-01

The core of future automotive lightweight materials is the joining technology of various material mixes. The type of joining will be essential, particularly in electrified propulsion systems, especially as an improved electrical energy transmission leads to a higher total efficiency of the vehicle. The most evident parts to start the optimization process are the traction battery, the electrical performance modules and the engines. Consequently aluminum plays a very central role for lightweight construction applications. However, the physical-technical requirements of components often require the combination with other materials. Thus the joining of mixed material connections is an essential key technology for many of the current developments, for example in the areas E-Mobility, solar energy and lightweight construction. Due to these advantages mixed material joints are already established in the automotive industry and laser beam remote welding is now a focus technology for mixed material connections. The secret of the laser welding process with mixed materials lies within the different areas of the melting phase diagram depending on the mixing ratio and the cooling down rate. According to that areas with unwanted, prim, intermetallic phases arise in the fusion zone. Therefore, laser welding of mixed material connections can currently only be used with additional filler in the automotive industry.

Radiological Source Localisation

DTIC Science & Technology

2007-07-01

activity. This algorithm was able to provide reasonable source estimates based on real data collected using the Low Cost Advanced Airborne...courses in Australia, Europe and the US. He is lecturing a post-graduate subject at Adelaide University (subject ”Multi-Sensor Data Fusion ”). He served on...technical committees of several international conferences, and is the Chair of the Fourth Australian Data Fusion Sym- posium (IDC-07). Dr Ristic won

The Light Ion Pulsed Power Induction Accelerator for ETF

DTIC Science & Technology

1995-07-01

the technical development necessary to demonstrate scientific and engineering feasibility for fusion energy production with a reprated driver. In...order for ETF to be cost effective, the accelerator system must be able to drive several target chambers which will test various Inertial Fusion ... Energy (IFE) reactor technologies. We envision an elevator system positioning and removing multiple target chambers from the center area of the ion beam

Preparation of calibration materials for microanalysis of Ti minerals by direct fusion of synthetic and natural materials: experience with LA-ICP-MS analysis of some important minor and trace elements in ilmenite and rutile.

PubMed

Odegård, M; Mansfeld, J; Dundas, S H

2001-08-01

Calibration materials for microanalysis of Ti minerals have been prepared by direct fusion of synthetic and natural materials by resistance heating in high-purity graphite electrodes. Synthetic materials were FeTiO3 and TiO2 reagents doped with minor and trace elements; CRMs for ilmenite, rutile, and a Ti-rich magnetite were used as natural materials. Problems occurred during fusion of Fe2O3-rich materials, because at atmospheric pressure Fe2O3 decomposes into Fe3O4 and O2 at 1462 degrees C. An alternative fusion technique under pressure was tested, but the resulting materials were characterized by extensive segregation and development of separate phases. Fe2O3-rich materials were therefore fused below this temperature, resulting in a form of sintering, without conversion of the materials into amorphous glasses. The fused materials were studied by optical microscopy and EPMA, and tested as calibration materials by inductively coupled plasma mass spectrometry, equipped with laser ablation for sample introduction (LA-ICP-MS). It was demonstrated that calibration curves based on materials of rutile composition, within normal analytical uncertainty, generally coincide with calibration curves based on materials of ilmenite composition. It is, therefore, concluded that LA-ICP-MS analysis of Ti minerals can with advantage be based exclusively on calibration materials prepared for rutile, thereby avoiding the special fusion problems related to oxide mixtures of ilmenite composition. It is documented that sintered materials were in good overall agreement with homogeneous glass materials, an observation that indicates that in other situations also sintered mineral concentrates might be a useful alternative for instrument calibration, e.g. as alternative to pressed powders.

Overview of the US Fusion Materials Sciences Program

NASA Astrophysics Data System (ADS)

Zinkle, Steven

2004-11-01

The challenging fusion reactor environment (radiation, heat flux, chemical compatibility, thermo-mechanical stresses) requires utilization of advanced materials to fulfill the promise of fusion to provide safe, economical, and environmentally acceptable energy. This presentation reviews recent experimental and modeling highlights on structural materials for fusion energy. The materials requirements for fusion will be compared with other demanding technologies, including high temperature turbine components, proposed Generation IV fission reactors, and the current NASA space fission reactor project to explore the icy moons of Jupiter. A series of high-performance structural materials have been developed by fusion scientists over the past ten years with significantly improved properties compared to earlier materials. Recent advances in the development of high-performance ferritic/martensitic and bainitic steels, nanocomposited oxide dispersion strengthened ferritic steels, high-strength V alloys, improved-ductility Mo alloys, and radiation-resistant SiC composites will be reviewed. Multiscale modeling is providing important insight on radiation damage and plastic deformation mechanisms and fracture mechanics behavior. Electron microscope in-situ straining experiments are uncovering fundamental physical processes controlling deformation in irradiated metals. Fundamental modeling and experimental studies are determining the behavior of transmutant helium in metals, enabling design of materials with improved resistance to void swelling and helium embrittlement. Recent chemical compatibility tests have identified promising new candidates for magnetohydrodynamic insulators in lithium-cooled systems, and have established the basic compatibility of SiC with Pb-Li up to high temperature. Research on advanced joining techniques such as friction stir welding will be described. ITER materials research will be briefly summarized.

Modelling structural and plasma facing materials for fusion power plants: Recent advances and outstanding issues in the EURATOM fusion materials programme

NASA Astrophysics Data System (ADS)

Boutard, Jean-Louis; Dudarev, Sergei; Rieth, Michael

2011-10-01

EFDA Fusion Materials Topical Group was established at the end of 2007 to coordinate the EU effort on the development of structural and protection materials able to withstand the very demanding operating conditions of a future DEMO power plant. Focusing on a selection of well identified materials issues, including the behaviour of Reduced Activation Ferritic-Martensitic steels, and W-alloys under the foreseen operation conditions in a future DEMO, this paper describes recent advances in physical modelling and experimental validation, contributing to the definition of chemical composition and microstructure of materials with improved in-service stability at high temperature, high neutron flux and intense ion bombardment.

Monte Carlo simulation of ion-material interactions in nuclear fusion devices

NASA Astrophysics Data System (ADS)

Nieto Perez, M.; Avalos-Zuñiga, R.; Ramos, G.

2017-06-01

One of the key aspects regarding the technological development of nuclear fusion reactors is the understanding of the interaction between high-energy ions coming from the confined plasma and the materials that the plasma-facing components are made of. Among the multiple issues important to plasma-wall interactions in fusion devices, physical erosion and composition changes induced by energetic particle bombardment are considered critical due to possible material flaking, changes to surface roughness, impurity transport and the alteration of physicochemical properties of the near surface region due to phenomena such as redeposition or implantation. A Monte Carlo code named MATILDA (Modeling of Atomic Transport in Layered Dynamic Arrays) has been developed over the years to study phenomena related to ion beam bombardment such as erosion rate, composition changes, interphase mixing and material redeposition, which are relevant issues to plasma-aided manufacturing of microelectronics, components on object exposed to intense solar wind, fusion reactor technology and other important industrial fields. In the present work, the code is applied to study three cases of plasma material interactions relevant to fusion devices in order to highlight the code's capabilities: (1) the Be redeposition process on the ITER divertor, (2) physical erosion enhancement in castellated surfaces and (3) damage to multilayer mirrors used on EUV diagnostics in fusion devices due to particle bombardment.

Plasma facing materials and components for future fusion devices—development, characterization and performance under fusion specific loading conditions

NASA Astrophysics Data System (ADS)

Linke, J.

2006-04-01

The plasma exposed components in existing and future fusion devices are strongly affected by the plasma material interaction processes. These mechanisms have a strong influence on the plasma performance; in addition they have major impact on the lifetime of the plasma facing armour and the joining interface between the plasma facing material (PFM) and the heat sink. Besides physical and chemical sputtering processes, high heat quasi-stationary fluxes during normal and intense thermal transients are of serious concern for the engineers who develop reliable wall components. In addition, the material and component degradation due to intense fluxes of energetic neutrons is another critical issue in D-T-burning fusion devices which requires extensive R&D. This paper presents an overview on the materials development and joining, the testing of PFMs and components, and the analysis of the neutron irradiation induced degradation.

Materials handbook for fusion energy systems

NASA Astrophysics Data System (ADS)

Davis, J. W.; Marchbanks, M. F.

A materials data book for use in the design and analysis of components and systems in near term experimental and commercial reactor concepts has been created by the Office of Fusion Energy. The handbook is known as the Materials Handbook for Fusion Energy Systems (MHFES) and is available to all organizations actively involved in fusion related research or system designs. Distribution of the MHFES and its data pages is handled by the Hanford Engineering Development Laboratory (HEDL), while its direction and content is handled by McDonnell Douglas Astronautics Company — St. Louis (MDAC-STL). The MHFES differs from other handbooks in that its format is geared more to the designer and structural analyst than to the materials scientist or materials engineer. The format that is used organizes the handbook by subsystems or components rather than material. Within each subsystem is information pertaining to material selection, specific material properties, and comments or recommendations on treatment of data. Since its inception a little more than a year ago, over 80 copies have been distributed to over 28 organizations consisting of national laboratories, universities, and private industries.

CTA with fluoroscopy image fusion guidance in endovascular complex aortic aneurysm repair.

PubMed

Sailer, A M; de Haan, M W; Peppelenbosch, A G; Jacobs, M J; Wildberger, J E; Schurink, G W H

2014-04-01

To evaluate the effect of intraoperative guidance by means of live fluoroscopy image fusion with computed tomography angiography (CTA) on iodinated contrast material volume, procedure time, and fluoroscopy time in endovascular thoraco-abdominal aortic repair. CTA with fluoroscopy image fusion road-mapping was prospectively evaluated in patients with complex aortic aneurysms who underwent fenestrated and/or branched endovascular repair (FEVAR/BEVAR). Total iodinated contrast material volume, overall procedure time, and fluoroscopy time were compared between the fusion group (n = 31) and case controls (n = 31). Reasons for potential fusion image inaccuracy were analyzed. Fusion imaging was feasible in all patients. Fusion image road-mapping was used for navigation and positioning of the devices and catheter guidance during access to target vessels. Iodinated contrast material volume and procedure time were significantly lower in the fusion group than in case controls (159 mL [95% CI 132-186 mL] vs. 199 mL [95% CI 170-229 mL], p = .037 and 5.2 hours [95% CI 4.5-5.9 hours] vs. 6.3 hours (95% CI 5.4-7.2 hours), p = .022). No significant differences in fluoroscopy time were observed (p = .38). Respiration-related vessel displacement, vessel elongation, and displacement by stiff devices as well as patient movement were identified as reasons for fusion image inaccuracy. Image fusion guidance provides added value in complex endovascular interventions. The technology significantly reduces iodinated contrast material dose and procedure time. Copyright © 2014 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

A Ratiometric Two-Photon Fluorescent Probe for Tracking the Lysosomal ATP Level: Direct in cellulo Observation of Lysosomal Membrane Fusion Processes.

PubMed

Jun, Yong Woong; Wang, Taejun; Hwang, Sekyu; Kim, Dokyoung; Ma, Donghee; Kim, Ki Hean; Kim, Sungjee; Jung, Junyang; Ahn, Kyo Han

2018-06-05

Vesicles exchange its contents through membrane fusion processes-kiss-and-run and full-collapse fusion. Indirect observation of these fusion processes using artificial vesicles enhanced our understanding on the molecular mechanisms involved. Direct observation of the fusion processes in a real biological system, however, remains a challenge owing to many technical obstacles. We disclose a ratiometric two-photon probe offering real-time tracking of lysosomal ATP with quantitative information for the first time. By applying the probe to two-photon live-cell imaging technique, lysosomal membrane fusion process in cells has been directly observed along with the concentration of its content-lysosomal ATP. Results show that the kiss-and-run process between lysosomes proceeds through repeating transient interactions with gradual content mixing, whereas the full-fusion process occurs at once. Furthermore, it is confirmed that both the fusion processes proceed with conservation of the content. Such a small-molecule probe exerts minimal disturbance and hence has potential for studying various biological processes associated with lysosomal ATP. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chemical Technology Division, Annual technical report, 1991

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1992-03-01

Highlights of the Chemical Technology (CMT) Division's activities during 1991 are presented. In this period, CMT conducted research and development in the following areas: (1) electrochemical technology, including advanced batteries and fuel cells; (2) technology for fluidized-bed combustion and coal-fired magnetohydrodynamics; (3) methods for treatment of hazardous and mixed hazardous/radioactive waste; (4) the reaction of nuclear waste glass and spent fuel under conditions expected for an unsaturated repository; (5) processes for separating and recovering transuranic elements from nuclear waste streams; (6) recovery processes for discharged fuel and the uranium blanket in the Integral Fast Reactor (IFR); (7) processes for removalmore » of actinides in spent fuel from commercial water-cooled nuclear reactors and burnup in IFRs; and (8) physical chemistry of selected materials in environments simulating those of fission and fusion energy systems. The Division also conducts basic research in catalytic chemistry associated with molecular energy resources; chemistry of superconducting oxides and other materials of interest with technological application; interfacial processes of importance to corrosion science, catalysis, and high-temperature superconductivity; and the geochemical processes involved in water-rock interactions occurring in active hydrothermal systems. In addition, the Analytical Chemistry Laboratory in CMT provides a broad range of analytical chemistry support services to the technical programs at Argonne National Laboratory (ANL).« less

Chemical Technology Division, Annual technical report, 1991

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1992-03-01

Highlights of the Chemical Technology (CMT) Division`s activities during 1991 are presented. In this period, CMT conducted research and development in the following areas: (1) electrochemical technology, including advanced batteries and fuel cells; (2) technology for fluidized-bed combustion and coal-fired magnetohydrodynamics; (3) methods for treatment of hazardous and mixed hazardous/radioactive waste; (4) the reaction of nuclear waste glass and spent fuel under conditions expected for an unsaturated repository; (5) processes for separating and recovering transuranic elements from nuclear waste streams; (6) recovery processes for discharged fuel and the uranium blanket in the Integral Fast Reactor (IFR); (7) processes for removalmore » of actinides in spent fuel from commercial water-cooled nuclear reactors and burnup in IFRs; and (8) physical chemistry of selected materials in environments simulating those of fission and fusion energy systems. The Division also conducts basic research in catalytic chemistry associated with molecular energy resources; chemistry of superconducting oxides and other materials of interest with technological application; interfacial processes of importance to corrosion science, catalysis, and high-temperature superconductivity; and the geochemical processes involved in water-rock interactions occurring in active hydrothermal systems. In addition, the Analytical Chemistry Laboratory in CMT provides a broad range of analytical chemistry support services to the technical programs at Argonne National Laboratory (ANL).« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

none,

The Fusion Energy Science Advisory Committee was asked to conduct a review of Fusion Materials Research Program (the Structural Materials portion of the Fusion Program) by Dr. Martha Krebs, Director of Energy Research for the Department of Energy. This request was motivated by the fact that significant changes have been made in the overall direction of the Fusion Program from one primarily focused on the milestones necessary to the construction of successively larger machines to one where the necessary scientific basis for an attractive fusion energy system is. better understood. It was in this context that the review of currentmore » scientific excellence and recommendations for future goals and balance within the Program was requested.« less

Current situation: New enthusiasm. [Nuclear fusion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

For decades the costly field of controlled nuclear fusion has been rocked by ups and downs, promise and problems. In spite of the many setbacks, scientists and DOE officials are determined to push ahead. [open quotes]We are very confident that by some time after the first decade of the next century, we will have a clear demonstration [of the technology] to give us unlimited energy....We are very excited about it,[close quotes] Energy Secretary Watkins said last spring in proposing a $360 million fusion energy budget for fiscal 1993. This article cites recent hey developments in terms of technical accomplishments, fundingmore » decisions, policy decisions, and efforts to collaborate internationally on controlled nuclear fusion. The International Thermonuclear Experimental Reactor is discussed also.« less

A technical case report on use of tubular retractors for anterior cervical spine surgery.

PubMed

Kulkarni, Arvind G; Patel, Ankit; Ankith, N V

2017-12-19

The authors put-forth this technical report to establish the feasibility of performing an anterior cervical corpectomy and fusion (ACCF) and a two-level anterior cervical discectomy and fusion (ACDF) using a minimally invasive approach with tubular retractors. First case: cervical spondylotic myelopathy secondary to a large postero-inferiorly migrated disc treated with corpectomy and reconstruction with a mesh cage and locking plate. Second case: cervical disc herniation with radiculopathy treated with a two-level ACDF. Both cases were operated with minimally invasive approach with tubular retractor using a single incision. Technical aspects and clinical outcomes have been reported. No intra or post-operative complications were encountered. Intra-operative blood loss was negligible. The patients had a cosmetic scar on healing. Standard procedure of placement of tubular retractors is sufficient for adequate surgical exposure with minimal invasiveness. Minimally invasive approach to anterior cervical spine with tubular retractors is feasible. This is the first report on use of minimally invasive approach for ACCF and two-level ACDF.

Plasma Physics Network Newsletter, no. 5

NASA Astrophysics Data System (ADS)

1992-08-01

The fifth Plasma Physics Network Newsletter (IAEA, Vienna, Aug. 1992) includes the following topics: (1) the availability of a list of the members of the Third World Plasma Research Network (TWPRN); (2) the announcement of the fourteenth IAEA International Conference on Plasma Physics and Controlled Nuclear Fusion Research to be held in Wuerzburg, Germany, from 30 Sep. to 7 Oct. 1992; (3) the announcement of a Technical Committee Meeting on research using small tokamaks, organized by the IAEA as a satellite meeting to the aforementioned fusion conference; (4) IAEA Fellowships and Scientific Visits for the use of workers in developing member states, and for which plasma researchers are encouraged to apply through Dr. D. Banner, Head, Physics Section, IAEA, P.O. Box 100, A-1400 Vienna, Austria; (5) the initiation in 1993 of a new Coordinated Research Programme (CRP) on 'Development of Software for Numerical Simulation and Data Processing in Fusion Energy Research', as well as a proposed CRP on 'Fusion Research in Developing Countries using Middle- and Small-Scale Plasma Devices'; (6) support from the International Centre for Theoretical Physics (ICTP) for meetings held in Third World countries; (7) a report by W. Usada on Fusion Research in Indonesia; (8) News on ITER; (9) the Technical Committee Meeting planned 8-12 Sep. 1992, Canada, on Tokamak Plasma Biasing; (10) software made available for the study of tokamak transport; (11) the electronic mail address of the TWPRN; (12) the FAX, e-mail, and postal address for contributions to this plasma physics network newsletter.

Recent progress in research on tungsten materials for nuclear fusion applications in Europe

NASA Astrophysics Data System (ADS)

Rieth, M.; Dudarev, S. L.; Gonzalez de Vicente, S. M.; Aktaa, J.; Ahlgren, T.; Antusch, S.; Armstrong, D. E. J.; Balden, M.; Baluc, N.; Barthe, M.-F.; Basuki, W. W.; Battabyal, M.; Becquart, C. S.; Blagoeva, D.; Boldyryeva, H.; Brinkmann, J.; Celino, M.; Ciupinski, L.; Correia, J. B.; De Backer, A.; Domain, C.; Gaganidze, E.; García-Rosales, C.; Gibson, J.; Gilbert, M. R.; Giusepponi, S.; Gludovatz, B.; Greuner, H.; Heinola, K.; Höschen, T.; Hoffmann, A.; Holstein, N.; Koch, F.; Krauss, W.; Li, H.; Lindig, S.; Linke, J.; Linsmeier, Ch.; López-Ruiz, P.; Maier, H.; Matejicek, J.; Mishra, T. P.; Muhammed, M.; Muñoz, A.; Muzyk, M.; Nordlund, K.; Nguyen-Manh, D.; Opschoor, J.; Ordás, N.; Palacios, T.; Pintsuk, G.; Pippan, R.; Reiser, J.; Riesch, J.; Roberts, S. G.; Romaner, L.; Rosiński, M.; Sanchez, M.; Schulmeyer, W.; Traxler, H.; Ureña, A.; van der Laan, J. G.; Veleva, L.; Wahlberg, S.; Walter, M.; Weber, T.; Weitkamp, T.; Wurster, S.; Yar, M. A.; You, J. H.; Zivelonghi, A.

2013-01-01

The current magnetic confinement nuclear fusion power reactor concepts going beyond ITER are based on assumptions about the availability of materials with extreme mechanical, heat, and neutron load capacity. In Europe, the development of such structural and armour materials together with the necessary production, machining, and fabrication technologies is pursued within the EFDA long-term fusion materials programme. This paper reviews the progress of work within the programme in the area of tungsten and tungsten alloys. Results, conclusions, and future projections are summarized for each of the programme's main subtopics, which are: (1) fabrication, (2) structural W materials, (3) W armour materials, and (4) materials science and modelling. It gives a detailed overview of the latest results on materials research, fabrication processes, joining options, high heat flux testing, plasticity studies, modelling, and validation experiments.

TBM/MTM for HTS-FNSF: An innovative testing strategy to qualify/validate fusion technologies for U.S. DEMO

DOE PAGES

El-Guebaly, Laila; Rowcliffe, Arthur; Menard, Jonathan; ...

2016-08-11

The qualification and validation of nuclear technologies are daunting tasks for fusion demonstration (DEMO) and power plants. This is particularly true for advanced designs that involve harsh radiation environment with 14 MeV neutrons and high-temperature operating regimes. This paper outlines the unique qualification and validation processes developed in the U.S., offering the only access to the complete fusion environment, focusing on the most prominent U.S. blanket concept (the dual cooled PbLi (DCLL)) along with testing new generations of structural and functional materials in dedicated test modules. The venue for such activities is the proposed Fusion Nuclear Science Facility (FNSF), whichmore » is viewed as an essential element of the U.S. fusion roadmap. A staged blanket testing strategy has been developed to test and enhance the DCLL blanket performance during each phase of FNSF D-T operation. A materials testing module (MTM) is critically important to include in the FNSF as well to test a broad range of specimens of future, more advanced generations of materials in a relevant fusion environment. Here, the most important attributes for MTM are the relevant He/dpa ratio (10–15) and the much larger specimen volumes compared to the 10–500 mL range available in the International Fusion Materials Irradiation Facility (IFMIF) and European DEMO-Oriented Neutron Source (DONES).« less

The emissivities of liquid metals at their fusion temperatures

NASA Technical Reports Server (NTRS)

Bonnell, D. W.; Treverton, J. A.; Valerga, A. J.; Margrave, J. L.

1972-01-01

A survey of the literature through 1969 shows an almost total lack of experimental emissivity data for metals in the liquid state. The emissivities for several transition metals and various other metals and compounds in the liquid state at their fusion temperatures have been determined. The technique used involves electromagnetic levitation-induction heating of the materials in an inert atmosphere. The brightness temperature of the liquid phase of the material is measured as the material is heated through fusion. Given a reliable value of the fusion temperature, which is available for most pure substances, one may readily calculate an emissivity for the liquid phase at the fusion temperatures. Even in cases where melting points are poorly known, the brightness temperatures are unique parameters, independent of the temperature scale and measured for a chemically defined system at a fixed point. Better emissivities may be recalculated as better melting point data become available.

Minimally Invasive Transforaminal Lumbar Interbody Fusion: Meta-analysis of the Fusion Rates. What is the Optimal Graft Material?

PubMed

Parajón, Avelino; Alimi, Marjan; Navarro-Ramirez, Rodrigo; Christos, Paul; Torres-Campa, Jose M; Moriguchi, Yu; Lang, Gernot; Härtl, Roger

2017-12-01

Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is an increasingly popular procedure with several potential advantages over traditional open TLIF. The current study aimed to compare fusion rates of different graft materials used in MIS-TLIF, via meta-analysis of the published literature. A Medline search was performed and a database was created including patient's type of graft, clinical outcome, fusion rate, fusion assessment modality, and duration of follow-up. Meta-analysis of the fusion rate was performed using StatsDirect software (StatsDirect Ltd, Cheshire, United Kingdom). A total of 1533 patients from 40 series were included. Fusion rates were high, ranging from 91.8% to 99%. The imaging modalities used to assess fusion were computed tomography scans (30%) and X-rays (70%). Comparison of all recombinant human bone morphogenetic protein (rhBMP) series with all non-rhBMP series showed fusion rates of 96.6% and 92.5%, respectively. The lowest fusion rate was seen with isolated use of autologous local bone (91.8%). The highest fusion rate was observed with combination of autologous local bone with bone extender and rhBMP (99.1%). The highest fusion rate without the use of BMP was seen with autologous local bone + bone extender (93.1%). The reported complication rate ranged from 0% to 35.71%. Clinical improvement was observed in all studies. Fusion rates are generally high with MIS-TLIF regardless of the graft material used. Given the potential complications of iliac bone harvesting and rhBMP, use of other bone graft options for MIS-TLIF is reasonable. The highest fusion rate without the use of rhBMP was seen with autologous local bone plus bone extender (93.1%). Published by Oxford University Press on behalf of Congress of Neurological Surgeons 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Variable control of neutron albedo in toroidal fusion devices

DOEpatents

Jassby, Daniel L.; Micklich, Bradley J.

1986-01-01

An arrangement is provided for controlling neutron albedo in toroidal fusion devices having inboard and outboard vacuum vessel walls for containment of the neutrons of a fusion plasma. Neutron albedo material is disposed immediately adjacent the inboard wall, and is movable, preferably in vertical directions, so as to be brought into and out of neutron modifying communication with the fusion neutrons. Neutron albedo material preferably comprises a liquid form, but may also take pebble, stringer and curtain-like forms. A neutron flux valve, rotatable about a vertical axis is also disclosed.

Study on ( n,t) Reactions of Zr, Nb and Ta Nuclei

NASA Astrophysics Data System (ADS)

Tel, E.; Yiğit, M.; Tanır, G.

2012-04-01

The world faces serious energy shortages in the near future. To meet the world energy demand, the nuclear fusion with safety, environmentally acceptability and economic is the best suited. Fusion is attractive as an energy source because of the virtually inexhaustible supply of fuel, the promise of minimal adverse environmental impact, and its inherent safety. Fusion will not produce CO2 or SO2 and thus will not contribute to global warming or acid rain. Furthermore, there are not radioactive nuclear waste problems in the fusion reactors. Although there have been significant research and development studies on the inertial and magnetic fusion reactor technology, there is still a long way to go to penetrate commercial fusion reactors to the energy market. Because, tritium self-sufficiency must be maintained for a commercial power plant. For self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. And also, the success of fusion power system is dependent on performance of the first wall, blanket or divertor systems. So, the performance of structural materials for fusion power systems, understanding nuclear properties systematic and working out of ( n,t) reaction cross sections are very important. Zirconium (Zr), Niobium (Nb) and Tantal (Ta) containing alloys are important structural materials for fusion reactors, accelerator-driven systems, and many other fields. In this study, ( n,t) reactions for some structural fusion materials such as 88,90,92,94,96Zr, 93,94,95Nb and 179,181Ta have been investigated. The calculated results are discussed andcompared with the experimental data taken from the literature.

First wall for polarized fusion reactors

DOEpatents

Greenside, H.S.; Budny, R.V.; Post, D.E. Jr.

1985-01-29

A first-wall or first-wall coating for use in a fusion reactor having polarized fuel may be formed of a low-Z non-metallic material having slow spin relaxation, i.e., a depolarization rate greater than 1 sec/sup -1/. Materials having these properties include hydrogenated and deuterated amorphous semiconductors. A method for preventing the rapid depolarization of a polarized plasma in a fusion device may comprise the step of providing a first-wall or first-wall coating formed of a low-Z, non-metallic material having a depolarization rate greater than 1 sec/sup -1/.

Distributed Multisensor Data Fusion under Unknown Correlation and Data Inconsistency

PubMed Central

Abu Bakr, Muhammad; Lee, Sukhan

2017-01-01

The paradigm of multisensor data fusion has been evolved from a centralized architecture to a decentralized or distributed architecture along with the advancement in sensor and communication technologies. These days, distributed state estimation and data fusion has been widely explored in diverse fields of engineering and control due to its superior performance over the centralized one in terms of flexibility, robustness to failure and cost effectiveness in infrastructure and communication. However, distributed multisensor data fusion is not without technical challenges to overcome: namely, dealing with cross-correlation and inconsistency among state estimates and sensor data. In this paper, we review the key theories and methodologies of distributed multisensor data fusion available to date with a specific focus on handling unknown correlation and data inconsistency. We aim at providing readers with a unifying view out of individual theories and methodologies by presenting a formal analysis of their implications. Finally, several directions of future research are highlighted. PMID:29077035

Accelerators for Fusion Materials Testing

NASA Astrophysics Data System (ADS)

Knaster, Juan; Okumura, Yoshikazu

Fusion materials research is a worldwide endeavor as old as the parallel one working toward the long term stable confinement of ignited plasma. In a fusion reactor, the preservation of the required minimum thermomechanical properties of the in-vessel components exposed to the severe irradiation and heat flux conditions is an indispensable factor for safe operation; it is also an essential goal for the economic viability of fusion. Energy from fusion power will be extracted from the 14 MeV neutron freed as a product of the deuterium-tritium fusion reactions; thus, this kinetic energy must be absorbed and efficiently evacuated and electricity eventually generated by the conventional methods of a thermal power plant. Worldwide technological efforts to understand the degradation of materials exposed to 14 MeV neutron fluxes >1018 m-2s-1, as expected in future fusion power plants, have been intense over the last four decades. Existing neutron sources can reach suitable dpa (“displacement-per-atom”, the figure of merit to assess materials degradation from being exposed to neutron irradiation), but the differences in the neutron spectrum of fission reactors and spallation sources do not allow one to unravel the physics and to anticipate the degradation of materials exposed to fusion neutrons. Fusion irradiation conditions can be achieved through Li (d, xn) nuclear reactions with suitable deuteron beam current and energy, and an adequate flowing lithium screen. This idea triggered in the late 1970s at Los Alamos National Laboratory (LANL) a campaign working toward the feasibility of continuous wave (CW) high current linacs framed by the Fusion Materials Irradiation Test (FMIT) project. These efforts continued with the Low Energy Demonstrating Accelerator (LEDA) (a validating prototype of the canceled Accelerator Production of Tritium (APT) project), which was proposed in 2002 to the fusion community as a 6.7MeV, 100mA CW beam injector for a Li (d, xn) source to bridge with the International Fusion Materials Irradiation Facility (IFMIF) under discussion at the time. Worldwide technological efforts are maturing soundly and the time for a fusion-relevant neutron source has arrived according to world fusion roadmaps; if decisions are taken we could count the next decade with a powerful source of 14 MeV neutrons thanks to the expected significant results of the Engineering Validation and Engineering Design Activity (EVEDA) phase of the IFMIF project. The accelerator know-how has matured in all possible aspects since the times of FMIT conception in the 1970s; today, operating 125 mA deuteron beam at 40 MeV in CW with high availabilities seems feasible thanks to the understanding of the beam halo physics and the three main technological breakthroughs in accelerator technology: (1) the ECR ion source for light ions developed at Chalk River Laboratories in the early 1990s, (2) the RFQ operation of H+ in CW with 100 mA demonstrated by LEDA in LANL in the late 1990s, and (3) the growing maturity of superconducting resonators for light hadrons and low β beams achieved in recent years.

Accelerators for Fusion Materials Testing

NASA Astrophysics Data System (ADS)

Knaster, Juan; Okumura, Yoshikazu

Fusion materials research is a worldwide endeavor as old as the parallel one working toward the long term stable confinement of ignited plasma. In a fusion reactor, the preservation of the required minimum thermomechanical properties of the in-vessel components exposed to the severe irradiation and heat flux conditions is an indispensable factor for safe operation; it is also an essential goal for the economic viability of fusion. Energy from fusion power will be extracted from the 14 MeV neutron freed as a product of the deuterium-tritium fusion reactions; thus, this kinetic energy must be absorbed and efficiently evacuated and electricity eventually generated by the conventional methods of a thermal power plant. Worldwide technological efforts to understand the degradation of materials exposed to 14 MeV neutron fluxes > 1018 m-2s-1, as expected in future fusion power plants, have been intense over the last four decades. Existing neutron sources can reach suitable dpa ("displacement-per-atom", the figure of merit to assess materials degradation from being exposed to neutron irradiation), but the differences in the neutron spectrum of fission reactors and spallation sources do not allow one to unravel the physics and to anticipate the degradation of materials exposed to fusion neutrons. Fusion irradiation conditions can be achieved through Li (d, xn) nuclear reactions with suitable deuteron beam current and energy, and an adequate flowing lithium screen. This idea triggered in the late 1970s at Los Alamos National Laboratory (LANL) a campaign working toward the feasibility of continuous wave (CW) high current linacs framed by the Fusion Materials Irradiation Test (FMIT) project. These efforts continued with the Low Energy Demonstrating Accelerator (LEDA) (a validating prototype of the canceled Accelerator Production of Tritium (APT) project), which was proposed in 2002 to the fusion community as a 6.7MeV, 100mA CW beam injector for a Li (d, xn) source to bridge with the International Fusion Materials Irradiation Facility (IFMIF) under discussion at the time. Worldwide technological efforts are maturing soundly and the time for a fusion-relevant neutron source has arrived according to world fusion roadmaps; if decisions are taken we could count the next decade with a powerful source of 14 MeV neutrons thanks to the expected significant results of the Engineering Validation and Engineering Design Activity (EVEDA) phase of the IFMIF project. The accelerator know-how has matured in all possible aspects since the times of FMIT conception in the 1970s; today, operating 125 mA deuteron beam at 40 MeV in CW with high availabilities seems feasible thanks to the understanding of the beam halo physics and the three main technological breakthroughs in accelerator technology: (1) the ECR ion source for light ions developed at Chalk River Laboratories in the early 1990s, (2) the RFQ operation of H+ in CW with 100 mA demonstrated by LEDA in LANL in the late 1990s, and (3) the growing maturity of superconducting resonators for light hadrons and low β beams achieved in recent years.

Energy and Technology Review, October 1990

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, K.C.; de Vore, L.; Gleason, K.

1990-10-01

This report discuss the following topics: History of Cold Fusion Experiments; LLNL Experiments on Cold Fusion; Roundtable Discussion on Cold Fusion; and Using MeV Ions To Characterize and Modify Materials.

Materials for DEMO and reactor applications—boundary conditions and new concepts

NASA Astrophysics Data System (ADS)

Coenen, J. W.; Antusch, S.; Aumann, M.; Biel, W.; Du, J.; Engels, J.; Heuer, S.; Houben, A.; Hoeschen, T.; Jasper, B.; Koch, F.; Linke, J.; Litnovsky, A.; Mao, Y.; Neu, R.; Pintsuk, G.; Riesch, J.; Rasinski, M.; Reiser, J.; Rieth, M.; Terra, A.; Unterberg, B.; Weber, Th; Wegener, T.; You, J.-H.; Linsmeier, Ch

2016-02-01

DEMO is the name for the first stage prototype fusion reactor considered to be the next step after ITER towards realizing fusion. For the realization of fusion energy especially, materials questions pose a significant challenge already today. Heat, particle and neutron loads are a significant problem to material lifetime when extrapolating to DEMO. For many of the issues faced, advanced materials solutions are under discussion or already under development. In particular, components such as the first wall and the divertor of the reactor can benefit from introducing new approaches such as composites or new alloys into the discussion. Cracking, oxidation as well as fuel management are driving issues when deciding for new materials. Here {{{W}}}{{f}}/{{W}} composites as well as strengthened CuCrZr components together with oxidation resilient tungsten alloys allow the step towards a fusion reactor. In addition, neutron induced effects such as transmutation, embrittlement and after-heat and activation are essential. Therefore, when designing a component an approach taking into account all aspects is required.

Proceedings of the Augmented VIsual Display (AVID) Research Workshop

NASA Technical Reports Server (NTRS)

Kaiser, Mary K. (Editor); Sweet, Barbara T. (Editor)

1993-01-01

The papers, abstracts, and presentations were presented at a three day workshop focused on sensor modeling and simulation, and image enhancement, processing, and fusion. The technical sessions emphasized how sensor technology can be used to create visual imagery adequate for aircraft control and operations. Participants from industry, government, and academic laboratories contributed to panels on Sensor Systems, Sensor Modeling, Sensor Fusion, Image Processing (Computer and Human Vision), and Image Evaluation and Metrics.

First clinical results of minimally invasive vector lumbar interbody fusion (MIS-VLIF) in spondylodiscitis and concomitant osteoporosis: a technical note.

PubMed

Rieger, Bernhard; Jiang, Hongzhen; Ruess, Daniel; Reinshagen, Clemens; Molcanyi, Marek; Zivcak, Jozef; Tong, Huaiyu; Schackert, Gabriele

2017-12-01

First description of MIS-VLIF, a minimally invasive lumbar stabilization, to evaluate its safety and feasibility in patients suffering from weak bony conditions (lumbar spondylodiscitis and/or osteoporosis). After informed consent, 12 patients suffering from lumbar spondylodiscitis underwent single level MIS-VLIF. Eight of them had a manifest osteoporosis, either. Pre- and postoperative clinical status was documented using numeric rating scale (NRS) for leg and back pain. In all cases, the optimal height for the cage was preoperatively determined using software-based range of motion and sagittal balance analysis. CT scans were obtained to evaluate correct placement of the construct and to verify fusion after 6 months. Since 2013, 12 patients with lumbar pyogenic spondylodiscitis underwent MIS-VLIF. Mean surgery time was 169 ± 28 min and average blood loss was less than 400 ml. Postoperative CT scans showed correct placement of the implants. Eleven patients showed considerable postoperative improvement in clinical scores. In one patient, we observed screw loosening. After documented bony fusion in the CT scan, the fixation system was removed in two cases to achieve lower material load. The load-bearing trajectories (vectors) of MIS-VLIF are different from those of conventional coaxial pedicle screw implantation. The dorsally converging construct combines the heads of the dorsoventral pedicle screws with laminar pedicle screws following cortical bone structures within a small approach. In case of lumbar spondylodiscitis and/or osteoporosis, MIS-VLIF relies on cortical bony structures for all screw vectors and the construct does not depend on conventional coaxial pedicle screws in the presence of inflamed, weak, cancellous or osteoporotic bone. MIS-VLIF allows full 360° lumbar fusion including cage implantation via a small, unilateral dorsal midline approach.

Designing Radiation Resistance in Materials for Fusion Energy

NASA Astrophysics Data System (ADS)

Zinkle, S. J.; Snead, L. L.

2014-07-01

Proposed fusion and advanced (Generation IV) fission energy systems require high-performance materials capable of satisfactory operation up to neutron damage levels approaching 200 atomic displacements per atom with large amounts of transmutant hydrogen and helium isotopes. After a brief overview of fusion reactor concepts and radiation effects phenomena in structural and functional (nonstructural) materials, three fundamental options for designing radiation resistance are outlined: Utilize matrix phases with inherent radiation tolerance, select materials in which vacancies are immobile at the design operating temperatures, or engineer materials with high sink densities for point defect recombination. Environmental and safety considerations impose several additional restrictions on potential materials systems, but reduced-activation ferritic/martensitic steels (including thermomechanically treated and oxide dispersion-strengthened options) and silicon carbide ceramic composites emerge as robust structural materials options. Materials modeling (including computational thermodynamics) and advanced manufacturing methods are poised to exert a major impact in the next ten years.

Porous biodegradable lumbar interbody fusion cage design and fabrication using integrated global-local topology optimization with laser sintering.

PubMed

Kang, Heesuk; Hollister, Scott J; La Marca, Frank; Park, Paul; Lin, Chia-Ying

2013-10-01

Biodegradable cages have received increasing attention for their use in spinal procedures involving interbody fusion to resolve complications associated with the use of nondegradable cages, such as stress shielding and long-term foreign body reaction. However, the relatively weak initial material strength compared to permanent materials and subsequent reduction due to degradation may be problematic. To design a porous biodegradable interbody fusion cage for a preclinical large animal study that can withstand physiological loads while possessing sufficient interconnected porosity for bony bridging and fusion, we developed a multiscale topology optimization technique. Topology optimization at the macroscopic scale provides optimal structural layout that ensures mechanical strength, while optimally designed microstructures, which replace the macroscopic material layout, ensure maximum permeability. Optimally designed cages were fabricated using solid, freeform fabrication of poly(ε-caprolactone) mixed with hydroxyapatite. Compression tests revealed that the yield strength of optimized fusion cages was two times that of typical human lumbar spine loads. Computational analysis further confirmed the mechanical integrity within the human lumbar spine, although the pore structure locally underwent higher stress than yield stress. This optimization technique may be utilized to balance the complex requirements of load-bearing, stress shielding, and interconnected porosity when using biodegradable materials for fusion cages.

Correlative Microscopy Combining Secondary Ion Mass Spectrometry and Electron Microscopy: Comparison of Intensity-Hue-Saturation and Laplacian Pyramid Methods for Image Fusion.

PubMed

Vollnhals, Florian; Audinot, Jean-Nicolas; Wirtz, Tom; Mercier-Bonin, Muriel; Fourquaux, Isabelle; Schroeppel, Birgit; Kraushaar, Udo; Lev-Ram, Varda; Ellisman, Mark H; Eswara, Santhana

2017-10-17

Correlative microscopy combining various imaging modalities offers powerful insights into obtaining a comprehensive understanding of physical, chemical, and biological phenomena. In this article, we investigate two approaches for image fusion in the context of combining the inherently lower-resolution chemical images obtained using secondary ion mass spectrometry (SIMS) with the high-resolution ultrastructural images obtained using electron microscopy (EM). We evaluate the image fusion methods with three different case studies selected to broadly represent the typical samples in life science research: (i) histology (unlabeled tissue), (ii) nanotoxicology, and (iii) metabolism (isotopically labeled tissue). We show that the intensity-hue-saturation fusion method often applied for EM-sharpening can result in serious image artifacts, especially in cases where different contrast mechanisms interplay. Here, we introduce and demonstrate Laplacian pyramid fusion as a powerful and more robust alternative method for image fusion. Both physical and technical aspects of correlative image overlay and image fusion specific to SIMS-based correlative microscopy are discussed in detail alongside the advantages, limitations, and the potential artifacts. Quantitative metrics to evaluate the results of image fusion are also discussed.

Effect of Stress Relief Annealing on Microstructure & Mechanical Properties of Welded Joints Between Low Alloy Carbon Steel and Stainless Steel

NASA Astrophysics Data System (ADS)

Nivas, R.; Das, G.; Das, S. K.; Mahato, B.; Kumar, S.; Sivaprasad, K.; Singh, P. K.; Ghosh, M.

2017-01-01

Two types of welded joints were prepared using low alloy carbon steel and austenitic stainless steel as base materials. In one variety, buttering material and weld metal were Inconel 82. In another type, buttering material and weld metal were Inconel 182. In case of Inconel 82, method of welding was GTAW. For Inconel 182, welding was done by SMAW technique. For one set of each joints after buttering, stress relief annealing was done at 923 K (650 °C) for 90 minutes before further joining with weld metal. Microstructural investigation and sub-size in situ tensile testing in scanning electron microscope were carried out for buttered-welded and buttered-stress relieved-welded specimens. Adjacent to fusion boundary, heat-affected zone of low alloy steel consisted of ferrite-pearlite phase combination. Immediately after fusion boundary in low alloy steel side, there was increase in matrix grain size. Same trend was observed in the region of austenitic stainless steel that was close to fusion boundary between weld metal-stainless steel. Close to interface between low alloy steel-buttering material, the region contained martensite, Type-I boundary and Type-II boundary. Peak hardness was obtained close to fusion boundary between low alloy steel and buttering material. In this respect, a minimum hardness was observed within buttering material. The peak hardness was shifted toward buttering material after stress relief annealing. During tensile testing no deformation occurred within low alloy steel and failure was completely through buttering material. Crack initiated near fusion boundary between low alloy steel-buttering material for welded specimens and the same shifted away from fusion boundary for stress relieved annealed specimens. This observation was at par with the characteristics of microhardness profile. In as welded condition, joints fabricated with Inconel 82 exhibited superior bond strength than the weld produced with Inconel 182. Stress relief annealing reduced the strength of transition joints and the reduction was maximum for specimen welded with Inconel 82.

RTO Technical Publications: A Quarterly Listing

NASA Technical Reports Server (NTRS)

2004-01-01

This is a listing of recent unclassified RTO technical publications for April 1, 2004 through June 30, 2004, processed by the NASA Center for AeroSpace Information. Topics covered include: heat transfer and cooling in propulsion and power systems; assessment of operator functional state; microwaves; aerodynamics in solid rocket propulsion; command, control, communications and intelligence modeling; personal protective equipment against anti-personnel mine blast; and data fusion and visualization.

Materials-related issues in the safety and licensing of nuclear fusion facilities

NASA Astrophysics Data System (ADS)

Taylor, N.; Merrill, B.; Cadwallader, L.; Di Pace, L.; El-Guebaly, L.; Humrickhouse, P.; Panayotov, D.; Pinna, T.; Porfiri, M.-T.; Reyes, S.; Shimada, M.; Willms, S.

2017-09-01

Fusion power holds the promise of electricity production with a high degree of safety and low environmental impact. Favourable characteristics of fusion as an energy source provide the potential for this very good safety and environmental performance. But to fully realize the potential, attention must be paid in the design of a demonstration fusion power plant (DEMO) or a commercial power plant to minimize the radiological hazards. These hazards arise principally from the inventory of tritium and from materials that become activated by neutrons from the plasma. The confinement of these radioactive substances, and prevention of radiation exposure, are the primary goals of the safety approach for fusion, in order to minimize the potential for harm to personnel, the public, and the environment. The safety functions that are implemented in the design to achieve these goals are dependent on the performance of a range of materials. Degradation of the properties of materials can lead to challenges to key safety functions such as confinement. In this paper the principal types of material that have some role in safety are recalled. These either represent a potential source of hazard or contribute to the amelioration of hazards; in each case the related issues are reviewed. The resolution of these issues lead, in some instances, to requirements on materials specifications or to limits on their performance.

How to improve the irradiation conditions for the International Fusion Materials Irradiation Facility

NASA Astrophysics Data System (ADS)

Daum, Eric

2000-12-01

The accelerator-based intense D-Li neutron source International Fusion Materials Irradiation Facility (IFMIF) provides very suitable irradiation conditions for fusion materials development with the attractive option of accelerated irradiations. Investigations show that a neutron moderator made of tungsten and placed in the IFMIF test cell can further improve the irradiation conditions. The moderator softens the IFMIF neutron spectrum by enhancing the fraction of low energy neutrons. For displacement damage, the ratio of point defects to cascades is more DEMO relevant and for tritium production in Li-based breeding ceramic materials it leads to a preferred production via the 6Li(n,t) 4He channel as it occurs in a DEMO breeding blanket.

The materials irradiation experiment for testing plasma facing materials at fusion relevant conditions

DOE PAGES

Garrison, L. M.; Zenobia, Samuel J.; Egle, Brian J.; ...

2016-08-01

The Materials Irradiation Experiment (MITE-E) was constructed at the University of Wisconsin-Madison Inertial Electrostatic Confinement Laboratory to test materials for potential use as plasma-facing materials (PFMs) in fusion reactors. PFMs in fusion reactors will be bombarded with x-rays, neutrons, and ions of hydrogen and helium. More needs to be understood about the interactions between the plasma and the materials to validate their use for fusion reactors. The MITE-E simulates some of the fusion reactor conditions by holding samples at temperatures up to 1000°C while irradiating them with helium or deuterium ions with energies from 10 to 150 keV. The ionmore » gun can irradiate the samples with ion currents of 20 μA–500 μA; the typical current used is 72 μA, which is an average flux of 9 × 10 14 ions/(cm 2 s). The ion gun uses electrostatic lenses to extract and shape the ion beam. A variable power (1-20 W), steady-state, Nd:YAG laser provides additional heating to maintain a constant sample temperature during irradiations. The ion beam current reaching the sample is directly measured and monitored in real-time during irradiations. The ion beam profile has been investigated using a copper sample sputtering experiment. In conclusion, the MITE-E has successfully been used to irradiate polycrystalline and single crystal tungsten samples with helium ions and will continue to be a source of important data for plasma interactions with materials.« less

The materials irradiation experiment for testing plasma facing materials at fusion relevant conditions.

PubMed

Garrison, L M; Zenobia, S J; Egle, B J; Kulcinski, G L; Santarius, J F

2016-08-01

The Materials Irradiation Experiment (MITE-E) was constructed at the University of Wisconsin-Madison Inertial Electrostatic Confinement Laboratory to test materials for potential use as plasma-facing materials (PFMs) in fusion reactors. PFMs in fusion reactors will be bombarded with x-rays, neutrons, and ions of hydrogen and helium. More needs to be understood about the interactions between the plasma and the materials to validate their use for fusion reactors. The MITE-E simulates some of the fusion reactor conditions by holding samples at temperatures up to 1000 °C while irradiating them with helium or deuterium ions with energies from 10 to 150 keV. The ion gun can irradiate the samples with ion currents of 20 μA-500 μA; the typical current used is 72 μA, which is an average flux of 9 × 10(14) ions/(cm(2) s). The ion gun uses electrostatic lenses to extract and shape the ion beam. A variable power (1-20 W), steady-state, Nd:YAG laser provides additional heating to maintain a constant sample temperature during irradiations. The ion beam current reaching the sample is directly measured and monitored in real-time during irradiations. The ion beam profile has been investigated using a copper sample sputtering experiment. The MITE-E has successfully been used to irradiate polycrystalline and single crystal tungsten samples with helium ions and will continue to be a source of important data for plasma interactions with materials.

The materials irradiation experiment for testing plasma facing materials at fusion relevant conditions

NASA Astrophysics Data System (ADS)

Garrison, L. M.; Zenobia, S. J.; Egle, B. J.; Kulcinski, G. L.; Santarius, J. F.

2016-08-01

The Materials Irradiation Experiment (MITE-E) was constructed at the University of Wisconsin-Madison Inertial Electrostatic Confinement Laboratory to test materials for potential use as plasma-facing materials (PFMs) in fusion reactors. PFMs in fusion reactors will be bombarded with x-rays, neutrons, and ions of hydrogen and helium. More needs to be understood about the interactions between the plasma and the materials to validate their use for fusion reactors. The MITE-E simulates some of the fusion reactor conditions by holding samples at temperatures up to 1000 °C while irradiating them with helium or deuterium ions with energies from 10 to 150 keV. The ion gun can irradiate the samples with ion currents of 20 μA-500 μA; the typical current used is 72 μA, which is an average flux of 9 × 1014 ions/(cm2 s). The ion gun uses electrostatic lenses to extract and shape the ion beam. A variable power (1-20 W), steady-state, Nd:YAG laser provides additional heating to maintain a constant sample temperature during irradiations. The ion beam current reaching the sample is directly measured and monitored in real-time during irradiations. The ion beam profile has been investigated using a copper sample sputtering experiment. The MITE-E has successfully been used to irradiate polycrystalline and single crystal tungsten samples with helium ions and will continue to be a source of important data for plasma interactions with materials.

Properties of radiation stable insulation composites for fusion magnet

NASA Astrophysics Data System (ADS)

Wu, Zhixiong; Huang, Rongjin; Huang, Chuanjun; Li, Laifeng

2017-09-01

High field superconducting magnets made of Nb3Al will be a suitable candidate for future fusion device which can provide magnetic field over 15T without critical current degradation caused by strain. The higher magnetic field and the larger current will produce a huge electromagnetic force. Therefore, it is necessary to develop high strength cryogenic structural materials and electrical insulation materials with excellent performance. On the other hand, superconducting magnets in fusion devices will experience significant nuclear radiation exposure during service. While typical structural materials like stainless steel and titanium have proven their ability to withstand these conditions, electrical insulation materials used in these coils have not fared as well. In fact, recent investigations have shown that electrical insulation breakdown is a limiting factor in the performance of high field magnets. The insulation materials used in the high field fusion magnets should be characterized by excellent mechanical properties, high radiation resistivity and good thermal conductivity. To meet these objectives, we designed various insulation materials based on epoxy resins and cyanate ester resins and investigated their processing characteristic and mechanical properties before and after irradiation at low temperature. In this paper, the recent progress of the radiation stable insulation composites for high field fusion magnet is presented. The materials have been irradiated by 60Co γ-ray irradiation in air at ambient temperature with a dose rate of 300 Gy/min. The total doses of 1 MGy, 5 MGy and 10 MGy were selected to the test specimens.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morgan, O.B. Jr.; Berry, L.A.; Sheffield, J.

This annual report on fusion energy discusses the progress on work in the following main topics: toroidal confinement experiments; atomic physics and plasma diagnostics development; plasma theory and computing; plasma-materials interactions; plasma technology; superconducting magnet development; fusion engineering design center; materials research and development; and neutron transport. (LSP)

Design and Demonstration of a Material-Plasma Exposure Target Station for Neutron Irradiated Samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rapp, Juergen; Aaron, A. M.; Bell, Gary L.

2015-10-20

Fusion energy is the most promising energy source for the future, and one of the most important problems to be solved progressing to a commercial fusion reactor is the identification of plasma-facing materials compatible with the extreme conditions in the fusion reactor environment. The development of plasma–material interaction (PMI) science and the technology of plasma-facing components are key elements in the development of the next step fusion device in the United States, the so-called Fusion Nuclear Science Facility (FNSF). All of these PMI issues and the uncertain impact of the 14-MeV neutron irradiation have been identified in numerous expert panelmore » reports to the fusion community. The 2007 Greenwald report classifies reactor plasma-facing materials (PFCs) and materials as the only Tier 1 issues, requiring a “. . . major extrapolation from the current state of knowledge, need for qualitative improvements and substantial development for both the short and long term.” The Greenwald report goes on to list 19 gaps in understanding and performance related to the plasma–material interface for the technology facilities needed for DEMO-oriented R&D and DEMO itself. Of the 15 major gaps, six (G7, G9, G10, G12, G13) can possibly be addressed with ORNL’s proposal of an advanced Material Plasma Exposure eXperiment. Establishing this mid-scale plasma materials test facility at ORNL is a key element in ORNL’s strategy to secure a leadership role for decades of fusion R&D. That is to say, our end goal is to bring the “signature facility” FNSF home to ORNL. This project is related to the pre-conceptual design of an innovative target station for a future Material–Plasma Exposure eXperiment (MPEX). The target station will be designed to expose candidate fusion reactor plasma-facing materials and components (PFMs and PFCs) to conditions anticipated in fusion reactors, where PFCs will be exposed to dense high-temperature hydrogen plasmas providing steady-state heat fluxes of 5–20 MW/m 2 and ion fluxes up to 10 24 m -2s -1. Since PFCs will have to withstand neutron irradiation displacement damage up to 50 dpa, the target station design must accommodate radioactive specimens (materials to be irradiated in HFIR or at SNS) to enable investigations of the impact of neutron damage on materials. Therefore, the system will have to be able to install and extract irradiated specimens using equipment and methods to avoid sample modification, control contamination, and minimize worker dose. Included in the design considerations will be an assessment of all the steps between neutron irradiation and post-exposure materials examination/characterization, as well as an evaluation of the facility hazard categorization. In particular, the factors associated with the acquisition of radioactive specimens and their preparation, transportation, experimental configuration at the plasma-specimen interface, post-plasma-exposure sample handling, and specimen preparation will be evaluated. Neutronics calculations to determine the dose rates of the samples were carried out for a large number of potential plasma-facing materials.« less

Overview of the IFMIF/EVEDA project

NASA Astrophysics Data System (ADS)

Knaster, J.; Garin, P.; Matsumoto, H.; Okumura, Y.; Sugimoto, M.; Arbeiter, F.; Cara, P.; Chel, S.; Facco, A.; Favuzza, P.; Furukawa, T.; Heidinger, R.; Ibarra, A.; Kanemura, T.; Kasugai, A.; Kondo, H.; Massaut, V.; Molla, J.; Micciche, G.; O'hira, S.; Sakamoto, K.; Yokomine, T.; Wakai, E.; the IFMIF/EVEDA Integrated Project Team

2017-10-01

IFMIF, the International Fusion Materials Irradiation Facility, is presently in its engineering validation and engineering design activities (EVEDA) phase under the Broader Approach Agreement. The engineering design activity (EDA) phase was successfully accomplished within the allocated time. The engineering validation activity (EVA) phase has focused on validating the Accelerator Facility (AF), the Target Facility and the Test Facility (TF) by constructing prototypes. The ELTL at JAEAc, Oarai successfully demonstrated the long-term stability of a Li flow under the IFMIF’s nominal operational conditions keeping the specified free-surface fluctuations below  ±1 mm in a continuous manner for 25 d. A full-scale prototype of the high flux test module (HFTM) was successfully tested in the HELOKA loop (KIT, Karlsruhe), where it was demonstrated that the irradiation temperature can be set individually and kept uniform. LIPAc, designed and constructed in European labs under the coordination of F4E, presently under installation and commissioning in the Rokkasho Fusion Institute, aims at validating the concept of IFMIF accelerators with a D+ beam of 125 mA continuous wave (CW) and 9 MeV. The commissioning phases of the H+/D+ beams at 100 keV are progressing and should be concluded in 2017; in turn, the commissioning of the 5 MeV beam is due to start during 2017. The D+ beam through the superconducting cavities is expected to be achieved within the Broader Approach Agreement time frame with the superconducting cryomodule being assembled in Rokkasho. The realisation of a fusion-relevant neutron source is a necessary step for the successful development of fusion. The ongoing success of the IFMIF/EVEDA involves ruling out concerns about potential technical showstoppers which were raised in the past. Thus, a situation has emerged where soon steps towards constructing a Li(d,xn) fusion-relevant neutron source could be taken, which is also justified in the light of costs which are marginal to those of a fusion plant. In Memoriam Yoshikazu Okumura who passed away on 6 March 2017.

Evaluation of Anterior Vertebral Interbody Fusion Using Osteogenic Mesenchymal Stem Cells Transplanted in Collagen Sponge.

PubMed

Yang, Wencheng; Dong, Youhai; Hong, Yang; Guang, Qian; Chen, Xujun

2016-05-01

The study used a rabbit model to achieve anterior vertebral interbody fusion using osteogenic mesenchymal stem cells (OMSCs) transplanted in collagen sponge. We investigated the effectiveness of graft material for anterior vertebral interbody fusion using a rabbit model by examining the OMSCs transplanted in collagen sponge. Anterior vertebral interbody fusion is commonly performed. Although autogenous bone graft remains the gold-standard fusion material, it requires a separate surgical procedure and is associated with significant short-term and long-term morbidity. Recently, mesenchymal stem cells from bone marrow have been studied in various fields, including posterolateral spinal fusion. Thus, we hypothesized that cultured OMSCs transplanted in porous collagen sponge could be used successfully even in anterior vertebral interbody fusion. Forty mature male White Zealand rabbits (weight, 3.5-4.5 kg) were randomly allocated to receive one of the following graft materials: porous collagen sponge plus cultured OMSCs (group I); porous collagen sponge alone (group II); autogenous bone graft (group III); and nothing (group IV). All animals underwent anterior vertebral interbody fusion at the L4/L5 level. The lumbar spine was harvested en bloc, and the new bone formation and spinal fusion was evaluated using radiographic analysis, microcomputed tomography, manual palpation test, and histologic examination at 8 and 12 weeks after surgery. New bone formation and bony fusion was evident as early as 8 weeks in groups I and III. And there was no statistically significant difference between 8 and 12 weeks. At both time points, by microcomputed tomography and histologic analysis, new bone formation was observed in both groups I and III, fibrous tissue was observed and there was no new bone in both groups II and IV; by manual palpation test, bony fusion was observed in 40% (4/10) of rabbits in group I, 70% (7/10) of rabbits in group III, and 0% (0/10) of rabbits in both groups II and IV. These findings suggest that mesenchymal stem cells that have been cultured with osteogenic differentiation medium and loaded with collagen sponge could induce bone formation and anterior vertebral interbody fusion. And the rabbit model we developed will be useful in evaluating the effects of graft materials for anterior vertebral interbody fusion. Further study is needed to determine the most appropriate carrier for OMSCs and the feasibility in the clinical setting.

Enhanced technologies for unattended ground sensor systems

NASA Astrophysics Data System (ADS)

Hartup, David C.

2010-04-01

Progress in several technical areas is being leveraged to advantage in Unattended Ground Sensor (UGS) systems. This paper discusses advanced technologies that are appropriate for use in UGS systems. While some technologies provide evolutionary improvements, other technologies result in revolutionary performance advancements for UGS systems. Some specific technologies discussed include wireless cameras and viewers, commercial PDA-based system programmers and monitors, new materials and techniques for packaging improvements, low power cueing sensor radios, advanced long-haul terrestrial and SATCOM radios, and networked communications. Other technologies covered include advanced target detection algorithms, high pixel count cameras for license plate and facial recognition, small cameras that provide large stand-off distances, video transmissions of target activity instead of still images, sensor fusion algorithms, and control center hardware. The impact of each technology on the overall UGS system architecture is discussed, along with the advantages provided to UGS system users. Areas of analysis include required camera parameters as a function of stand-off distance for license plate and facial recognition applications, power consumption for wireless cameras and viewers, sensor fusion communication requirements, and requirements to practically implement video transmission through UGS systems. Examples of devices that have already been fielded using technology from several of these areas are given.

Synchronized fusion development considering physics, materials and heat transfer

NASA Astrophysics Data System (ADS)

Wong, C. P. C.; Liu, Y.; Duan, X. R.; Xu, M.; Li, Q.; Feng, K. M.; Zheng, G. Y.; Li, Z. X.; Wang, X. Y.; Li, B.; Zhang, G. S.

2017-12-01

Significant achievements have been made in the last 60 years in the development of fusion energy with the tokamak configuration. Based on the accumulated knowledge, the world is embarking on the construction and operation of ITER (International Thermonuclear Experimental Reactor) with a production of 500 MWf fusion power and the demonstration of physics Q  =  10. ITER will demonstrate D-T burn physics for a duration of a few hundred seconds to prepare for the next long-burn or steady state nuclear testing tokamak operating at much higher neutron fluence. With the evolution into a steady state nuclear device, such as the China Fusion Engineering Test Reactor (CFETR), it is necessary to examine the boundary conditions imposed by the combined development of tokamak physics, fusion materials and fusion technology for a reactor. The development of ferritic steel alloys as the structural material suitable for use at high neutron fluence leads to the use of helium as the most likely reactor coolant. This points to the fundamental technology limitation on the removal of chamber wall maximum heat flux at around 1 MW m-2 and an average heat flux of 0.1 MW m-2 for the next test reactor. Future reactor performance will then depend on the control of spatial and temporal edge heat flux peaking in order to increase the average heat flux to the chamber wall. With these severe material and technological limitations, system studies were used to scope out a few robust steady state synchronized fusion reactor (SFR) designs. As an example, a low fusion power design at 131.6 MWf, which can satisfy steady state design requirements, would have a major radius of 5.5 m and minor radius of 1.6 m. Such a design with even more advanced structural materials like W f/W composite could allow higher performance and provide a net electrical production of 62 MWe. These can be incorporated into the CFETR program.

EDITORIAL: Plasma Surface Interactions for Fusion

NASA Astrophysics Data System (ADS)

2006-05-01

Because plasma-boundary physics encompasses some of the most important unresolved issues for both the International Thermonuclear Experimental Reactor (ITER) project and future fusion power reactors, there is a strong interest in the fusion community for better understanding and characterization of plasma wall interactions. Chemical and physical sputtering cause the erosion of the limiters/divertor plates and vacuum vessel walls (made of C, Be and W, for example) and degrade fusion performance by diluting the fusion fuel and excessively cooling the core, while carbon redeposition could produce long-term in-vessel tritium retention, degrading the superior thermo-mechanical properties of the carbon materials. Mixed plasma-facing materials are proposed, requiring optimization for different power and particle flux characteristics. Knowledge of material properties as well as characteristics of the plasma material interaction are prerequisites for such optimizations. Computational power will soon reach hundreds of teraflops, so that theoretical and plasma science expertise can be matched with new experimental capabilities in order to mount a strong response to these challenges. To begin to address such questions, a Workshop on New Directions for Advanced Computer Simulations and Experiments in Fusion-Related Plasma Surface Interactions for Fusion (PSIF) was held at the Oak Ridge National Laboratory from 21 to 23 March, 2005. The purpose of the workshop was to bring together researchers in fusion related plasma wall interactions in order to address these topics and to identify the most needed and promising directions for study, to exchange opinions on the present depth of knowledge of surface properties for the main fusion-related materials, e.g., C, Be and W, especially for sputtering, reflection, and deuterium (tritium) retention properties. The goal was to suggest the most important next steps needed for such basic computational and experimental work to be facilitated by researchers in fusion, material, and physical sciences. Representatives from many fusion research laboratories attended, and 25 talks were given, the majority of them making up the content of these Workshop proceedings. The presentations of all talks and further information on the Workshop are available at http://www-cfadc.phy.ornl.gov/psif/home.html. The workshop talks dealt with identification of needs from the perspective of integrated fusion simulation and ITER design, recent developments and perspectives on computation of plasma-facing surface properties using the current and expected new generation of computation capability, and with the status of dedicated laboratory experiments which characterize the underlying processes of PSIF. The Workshop summary and conclusions are being published in Nuclear Fusion 45 (2005). We are indebted to Lynda Saddiq and Fay Ownby, secretaries in the Physics Division of ORNL, whose special efforts, devotion, and expertise made possible both the Workshop and these Proceedings. J T Hogan, P S Krstic and F W Meyer Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6372, USA

Activation characteristics of candidate structural materials for a near-term Indian fusion reactor and the impact of their impurities on design considerations

NASA Astrophysics Data System (ADS)

H, L. SWAMI; C, DANANI; A, K. SHAW

2018-06-01

Activation analyses play a vital role in nuclear reactor design. Activation analyses, along with nuclear analyses, provide important information for nuclear safety and maintenance strategies. Activation analyses also help in the selection of materials for a nuclear reactor, by providing the radioactivity and dose rate levels after irradiation. This information is important to help define maintenance activity for different parts of the reactor, and to plan decommissioning and radioactive waste disposal strategies. The study of activation analyses of candidate structural materials for near-term fusion reactors or ITER is equally essential, due to the presence of a high-energy neutron environment which makes decisive demands on material selection. This study comprises two parts; in the first part the activation characteristics, in a fusion radiation environment, of several elements which are widely present in structural materials, are studied. It reveals that the presence of a few specific elements in a material can diminish its feasibility for use in the nuclear environment. The second part of the study concentrates on activation analyses of candidate structural materials for near-term fusion reactors and their comparison in fusion radiation conditions. The structural materials selected for this study, i.e. India-specific Reduced Activation Ferritic‑Martensitic steel (IN-RAFMS), P91-grade steel, stainless steel 316LN ITER-grade (SS-316LN-IG), stainless steel 316L and stainless steel 304, are candidates for use in ITER either in vessel components or test blanket systems. Tungsten is also included in this study because of its use for ITER plasma-facing components. The study is carried out using the reference parameters of the ITER fusion reactor. The activation characteristics of the materials are assessed considering the irradiation at an ITER equatorial port. The presence of elements like Nb, Mo, Co and Ta in a structural material enhance the activity level as well as the dose level, which has an impact on design considerations. IN-RAFMS was shown to be a more effective low-activation material than SS-316LN-IG.

Method of constructing a microwave antenna

NASA Technical Reports Server (NTRS)

Ngo, Phong (Inventor); Arndt, G. Dickey (Inventor); Carl, James (Inventor)

2003-01-01

A method, simulation, and apparatus are provided that are highly suitable for treatment of benign prostatic hyperplasia (BPH). A catheter is disclosed that includes a small diameter disk loaded monopole antenna surrounded by fusion material having a high heat of fusion and a melting point preferably at or near body temperature. Microwaves from the antenna heat prostatic tissue to promote necrosing of the prostatic tissue that relieves the pressure of the prostatic tissue against the urethra as the body reabsorbs the necrosed or dead tissue. The fusion material keeps the urethra cool by means of the heat of fusion of the fusion material. This prevents damage to the urethra while the prostatic tissue is necrosed. A computer simulation is provided that can be used to predict the resulting temperature profile produced in the prostatic tissue. By changing the various control features of the catheter and method of applying microwave energy a temperature profile can be predicted and produced that is similar to the temperature profile desired for the particular patient.

Method of Constructing a Microwave Antenna

NASA Technical Reports Server (NTRS)

Arndt, G. Dickey (Inventor); Carl, James (Inventor); Ngo, Phong (Inventor)

2003-01-01

A method, simulation, and apparatus are provided that are highly suitable for treatment of benign prostatic hyperplasia (BPH). A catheter is disclosed that includes a small diameter disk loaded monopole antenna surrounded by fusion material having a high heat of fusion and a melting point preferably at or near body temperature. Microwaves from the antenna heat prostatic tissue to promote necrosing of the prostatic tissue that relieves the pressure of the prostatic tissue against the urethra as the body reabsorbs the necrosed or dead tissue. The fusion material keeps the urethra cool by means of the heat of fusion of the fusion material. This prevents damage to the urethra while the prostatic tissue is necrosed. A computer simulation is provided that can be used to predict the resulting temperature profile produced in the prostatic tissue. By changing the various control features of the catheter and method of applying microwave energy a temperature profile can be predicted and produced that is similar to the temperature profile desired for the particular patient.

Method for selective thermal ablation

NASA Technical Reports Server (NTRS)

Ngo, Phong (Inventor); Arndt, G. Dickey (Inventor); Raffoul, George W. (Inventor); Carl, James (Inventor)

2003-01-01

A method, simulation, and apparatus are provided that are highly suitable for treatment of benign prostatic hyperplasia (BPH). A catheter is disclosed that includes a small diameter disk loaded monopole antenna surrounded by fusion material having a high heat of fusion and a melting point preferably at or near body temperature. Microwaves from the antenna heat prostatic tissue to promote necrosing of the prostatic tissue that relieves the pressure of the prostatic tissue against the urethra as the body reabsorbs the necrosed or dead tissue. The fusion material keeps the urethra cool by means of the heat of fusion of the fusion material. This prevents damage to the urethra while the prostatic tissue is necrosed. A computer simulation is provided that can be used to predict the resulting temperature profile produced in the prostatic tissue. By changing the various control features of the catheter and method of applying microwave energy a temperature profile can be predicted and produced that is similar to the temperature profile desired for the particular patient.

Method for Selective Thermal Ablation

NASA Technical Reports Server (NTRS)

Arndt, G. Dickey (Inventor); Carl, James (Inventor); Ngo, Phong (Inventor); Raffoul, George W. (Inventor)

2003-01-01

A method, simulation, and apparatus are provided that are highly suitable for treatment of benign prostatic hyperplasia (BPH). A catheter is disclosed that includes a small diameter disk loaded monopole antenna surrounded by fusion material having a high heat of fusion and a melting point preferably at or near body temperature. Microwaves from the antenna heat prostatic tissue to promote necrosing of the prostatic tissue that relieves the pressure of the prostatic tissue against the urethra as the body reabsorbs the necrosed or dead tissue. The fusion material keeps the urethra cool by means of the heat of fusion of the fusion material. This prevents damage to the urethra while the prostatic tissue is necrosed. A computer simulation is provided that can be used to predict the resulting temperature profile produced in the prostatic tissue. By changing the various control features of the catheter and method of applying microwave energy a temperature profile can be predicted and produced that is similar to the temperature profile desired for the particular patient.

Transcatheter Microwave Antenna

NASA Technical Reports Server (NTRS)

Arndt, Dickey G. (Inventor); Carl, James R. (Inventor); Ngo, Phong (Inventor); Raffoul, George W. (Inventor)

2001-01-01

A method, simulation, and apparatus are provided that are highly suitable for treatment of benign prostatic hyperplasia (BPH). A catheter is disclosed that includes a small diameter disk loaded monopole antenna surrounded by fusion material having a high heat of fusion and a melting point preferably at or near body temperature. Microwaves from the antenna heat prostatic tissue to promote necrosing of the prostatic tissue that relieves the pressure of the prostatic tissue against the urethra as the body reabsorbs the necrosed or dead tissue. The fusion material keeps the urethra cool by means of the heat of fusion of the fusion material. This prevents damage to the urethra while the prostatic tissue is necrosed. A computer simulation is provided that can be used to predict the resulting temperature profile produced in the prostatic tissue. By changing the various control features of the catheter and method of applying microwave energy a temperature profile can be predicted and produced that is similar to the temperature profile desired for the particular patient.

Technical Topic 3.2.2.d Bayesian and Non-Parametric Statistics: Integration of Neural Networks with Bayesian Networks for Data Fusion and Predictive Modeling

DTIC Science & Technology

2016-05-31

and included explosives such as TATP, HMTD, RDX, RDX, ammonium nitrate , potassium perchlorate, potassium nitrate , sugar, and TNT. The approach...Distribution Unlimited UU UU UU UU 31-05-2016 15-Apr-2014 14-Jan-2015 Final Report: Technical Topic 3.2.2. d Bayesian and Non- parametric Statistics...of Papers published in non peer-reviewed journals: Final Report: Technical Topic 3.2.2. d Bayesian and Non-parametric Statistics: Integration of Neural

[MRI/TRUS fusion-guided prostate biopsy : Value in the context of focal therapy].

PubMed

Franz, T; von Hardenberg, J; Blana, A; Cash, H; Baumunk, D; Salomon, G; Hadaschik, B; Henkel, T; Herrmann, J; Kahmann, F; Köhrmann, K-U; Köllermann, J; Kruck, S; Liehr, U-B; Machtens, S; Peters, I; Radtke, J P; Roosen, A; Schlemmer, H-P; Sentker, L; Wendler, J J; Witzsch, U; Stolzenburg, J-U; Schostak, M; Ganzer, R

2017-02-01

Several systems for MRI/TRUS fusion-guided biopsy of the prostate are commercially available. Many studies have shown superiority of fusion systems for tumor detection and diagnostic quality compared to random biopsy. The benefit of fusion systems in focal therapy of prostate cancer (PC) is less clear. Critical considerations of fusion systems for planning and monitoring of focal therapy of PC were investigated. A systematic literature review of available fusion systems for the period 2013-5/2016 was performed. A checklist of technical details, suitability for special anatomic situations and suitability for focal therapy was established by the German working group for focal therapy (Arbeitskreis fokale und Mikrotherapie). Eight fusion systems were considered (Artemis™, BioJet, BiopSee®, iSR´obot™ Mona Lisa, Hitachi HI-RVS, UroNav and Urostation®). Differences were found for biopsy mode (transrectal, perineal, both), fusion mode (elastic or rigid), navigation (image-based, electromagnetic sensor-based or mechanical sensor-based) and space requirements. Several consensus groups recommend fusion systems for focal therapy. Useful features are "needle tracking" and compatibility between fusion system and treatment device (available for Artemis™, BiopSee® and Urostation® with Focal One®; BiopSee®, Hitachi HI-RVS with NanoKnife®; BioJet, BiopSee® with cryoablation, brachytherapy). There are a few studies for treatment planning. However, studies on treatment monitoring after focal therapy are missing.

An overview of LLNL high-energy short-pulse technology for advanced radiography of laser fusion experiments

NASA Astrophysics Data System (ADS)

Barty, C. P. J.; Key, M.; Britten, J.; Beach, R.; Beer, G.; Brown, C.; Bryan, S.; Caird, J.; Carlson, T.; Crane, J.; Dawson, J.; Erlandson, A. C.; Fittinghoff, D.; Hermann, M.; Hoaglan, C.; Iyer, A.; Jones, L., II; Jovanovic, I.; Komashko, A.; Landen, O.; Liao, Z.; Molander, W.; Mitchell, S.; Moses, E.; Nielsen, N.; Nguyen, H.-H.; Nissen, J.; Payne, S.; Pennington, D.; Risinger, L.; Rushford, M.; Skulina, K.; Spaeth, M.; Stuart, B.; Tietbohl, G.; Wattellier, B.

2004-12-01

The technical challenges and motivations for high-energy, short-pulse generation with NIF and possibly other large-scale Nd : glass lasers are reviewed. High-energy short-pulse generation (multi-kilojoule, picosecond pulses) will be possible via the adaptation of chirped pulse amplification laser techniques on NIF. Development of metre-scale, high-efficiency, high-damage-threshold final optics is a key technical challenge. In addition, deployment of high energy petawatt (HEPW) pulses on NIF is constrained by existing laser infrastructure and requires new, compact compressor designs and short-pulse, fibre-based, seed-laser systems. The key motivations for HEPW pulses on NIF is briefly outlined and includes high-energy, x-ray radiography, proton beam radiography, proton isochoric heating and tests of the fast ignitor concept for inertial confinement fusion.

Liquid Metals as Plasma-facing Materials for Fusion Energy Systems: From Atoms to Tokamaks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stone, Howard A.; Koel, Bruce E.; Bernasek, Steven L.

The objective of our studies was to advance our fundamental understanding of liquid metals as plasma-facing materials for fusion energy systems, with a broad scope: from atoms to tokamaks. The flow of liquid metals offers solutions to significant problems of the plasma-facing materials for fusion energy systems. Candidate metals include lithium, tin, gallium, and their eutectic combinations. However, such liquid metal solutions can only be designed efficiently if a range of scientific and engineering issues are resolved that require advances in fundamental fluid dynamics, materials science and surface science. In our research we investigated a range of significant and timelymore » problems relevant to current and proposed engineering designs for fusion reactors, including high-heat flux configurations that are being considered by leading fusion energy groups world-wide. Using experimental and theoretical tools spanning atomistic to continuum descriptions of liquid metals, and bridging surface chemistry, wetting/dewetting and flow, our research has advanced the science and engineering of fusion energy materials and systems. Specifically, we developed a combined experimental and theoretical program to investigate flows of liquid metals in fusion-relevant geometries, including equilibrium and stability of thin-film flows, e.g. wetting and dewetting, effects of electromagnetic and thermocapillary fields on liquid metal thin-film flows, and how chemical interactions and the properties of the surface are influenced by impurities and in turn affect the surface wetting characteristics, the surface tension, and its gradients. Because high-heat flux configurations produce evaporation and sputtering, which forces rearrangement of the liquid, and any dewetting exposes the substrate to damage from the plasma, our studies addressed such evaporatively driven liquid flows and measured and simulated properties of the different bulk phases and material interfaces. The range of our studies included (i) quantum mechanical calculations that allow inclusion of many thousands of atoms for the characterization of the interface of liquid metals exposed to continuous bombardment by deuterium and tritium as expected in fusion, (ii) molecular dynamics studies of the phase behavior of liquid metals, which (a) utilize thermodynamic properties computed using our quantum mechanical calculations and (b) establish material and wetting properties of the liquid metals, including relevant eutectics, (iii) experimental investigations of the surface science of liquid metals, interacting both with the solid substrate as well as gaseous species, and (iv) fluid dynamical studies that incorporate the material and surface science results of (ii) and (iii) in order to characterize flow in capillary porous materials and the thin-film flow along curved boundaries, both of which are potentially major components of plasma-facing materials. The outcome of these integrated studies was new understanding that enables developing design rules useful for future developments of the plasma-facing components critical to the success of fusion energy systems.« less

Chemical Technology Division annual technical report, 1992

DOE Office of Scientific and Technical Information (OSTI.GOV)

Battles, J.E.; Myles, K.M.; Laidler, J.J.

1993-06-01

In this period, CMT conducted research and development in the following areas: (1) electrochemical technology, including advanced batteries and fuel cells; (2) technology for fluidized-bed combustion and coal-fired magnetohydrodynamics; (3) methods for treatment of hazardous waste, mixed hazardous/radioactive waste, and municipal solid waste; (4) the reaction of nuclear waste glass and spent fuel under conditions expected for an unsaturated repository; (5) processes for separating and recovering transuranic elements from nuclear waste streams, treating water contaminated with volatile organics, and concentrating radioactive waste streams; (6) recovery processes for discharged fuel and the uranium blanket in the Integral Fast Reactor (EFR); (7)more » processes for removal of actinides in spent fuel from commercial water-cooled nuclear reactors and burnup in IFRs; and (8) physical chemistry of selected materials (corium; Fe-U-Zr, tritium in LiAlO{sub 2} in environments simulating those of fission and fusion energy systems. The Division also conducts basic research in catalytic chemistry associated with molecular energy resources and novel` ceramic precursors; materials chemistry of superconducting oxides, electrified metal/solution interfaces, and molecular sieve structures; and the geochemical processes involved in water-rock interactions occurring in active hydrothermal systems. In addition, the Analytical Chemistry Laboratory in CMT provides a broad range of analytical chemistry support services to the technical programs at Argonne National Laboratory (ANL).« less

Evaluation of a polyetheretherketone (PEEK) titanium composite interbody spacer in an ovine lumbar interbody fusion model: biomechanical, microcomputed tomographic, and histologic analyses.

PubMed

McGilvray, Kirk C; Waldorff, Erik I; Easley, Jeremiah; Seim, Howard B; Zhang, Nianli; Linovitz, Raymond J; Ryaby, James T; Puttlitz, Christian M

2017-12-01

The most commonly used materials used for interbody cages are titanium metal and polymer polyetheretherketone (PEEK). Both of these materials have demonstrated good biocompatibility. A major disadvantage associated with solid titanium cages is their radiopacity, limiting the postoperative monitoring of spinal fusion via standard imaging modalities. However, PEEK is radiolucent, allowing for a temporal assessment of the fusion mass by clinicians. On the other hand, PEEK is hydrophobic, which can limit bony ingrowth. Although both PEEK and titanium have demonstrated clinical success in obtaining a solid spinal fusion, innovations are being developed to improve fusion rates and to create stronger constructs using hybrid additive manufacturing approaches by incorporating both materials into a single interbody device. The purpose of this study was to examine the interbody fusion characteristic of a PEEK Titanium Composite (PTC) cage for use in lumbar fusion. Thirty-four mature female sheep underwent two-level (L 2 -L 3 and L 4 -L 5 ) interbody fusion using either a PEEK or a PTC cage (one of each per animal). Animals were sacrificed at 0, 8, 12, and 18 weeks post surgery. Post sacrifice, each surgically treated functional spinal unit underwent non-destructive kinematic testing, microcomputed tomography scanning, and histomorphometric analyses. Relative to the standard PEEK cages, the PTC constructs demonstrated significant reductions in ranges of motion and a significant increase in stiffness. These biomechanical findings were reinforced by the presence of significantly more bone at the fusion site as well as ingrowth into the porous end plates. Overall, the results indicate that PTC interbody devices could potentially lead to a more robust intervertebral fusion relative to a standard PEEK device in a clinical setting. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

A Review on the Potential Use of Austenitic Stainless Steels in Nuclear Fusion Reactors

NASA Astrophysics Data System (ADS)

Şahin, Sümer; Übeyli, Mustafa

2008-12-01

Various engineering materials; austenitic stainless steels, ferritic/martensitic steels, vanadium alloys, refractory metals and composites have been suggested as candidate structural materials for nuclear fusion reactors. Among these structural materials, austenitic steels have an advantage of extensive technological database and lower cost compared to other non-ferrous candidates. Furthermore, they have also advantages of very good mechanical properties and fission operation experience. Moreover, modified austenitic stainless (Ni and Mo free) have relatively low residual radioactivity. Nevertheless, they can't withstand high neutron wall load which is required to get high power density in fusion reactors. On the other hand, a protective flowing liquid wall between plasma and solid first wall in these reactors can eliminate this restriction. This study presents an overview of austenitic stainless steels considered to be used in fusion reactors.

Activation Inventories after Exposure to DD/DT Neutrons in Safety Analysis of Nuclear Fusion Installations.

PubMed

Stankunas, Gediminas; Cufar, Aljaz; Tidikas, Andrius; Batistoni, Paola

2017-11-23

Irradiations with 14 MeV fusion neutrons are planned at Joint European Torus (JET) in DT operations with the objective to validate the calculation of the activation of structural materials in functional materials expected in ITER and fusion plants. This study describes the activation and dose rate calculations performed for materials irradiated throughout the DT plasma operation during which the samples of real fusion materials are exposed to 14 MeV neutrons inside the JET vacuum vessel. Preparatory activities are in progress during the current DD operations with dosimetry foils to measure the local neutron fluence and spectrum at the sample irradiation position. The materials included those used in the manufacturing of the main in-vessel components, such as ITER-grade W, Be, CuCrZr, 316 L(N) and the functional materials used in diagnostics and heating systems. The neutron-induced activities and dose rates at shutdown were calculated by the FISPACT code, using the neutron fluxes and spectra that were provided by the preceding MCNP neutron transport calculations. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Fast ion transport at a gas-metal interface

DOE PAGES

McDevitt, Christopher J.; Tang, Xian-Zhu; Guo, Zehua

2017-11-06

Fast ion transport and the resulting fusion yield reduction are computed at a gas-metal interface. The extent of fusion yield reduction is observed to depend sensitively on the charge state of the surrounding pusher material and the width of the atomically mixed region. These sensitivities suggest that idealized boundary conditions often implemented at the gas-pusher interface for the purpose of estimating fast ion loss will likely overestimate fusion reactivity reduction in several important limits. Additionally, the impact of a spatially complex material interface is investigated by considering a collection of droplets of the pusher material immersed in a DT plasma.more » It is found that for small Knudsen numbers, the extent of fusion yield reduction scales with the surface area of the material interface. As the Knudsen number is increased, but, the simple surface area scaling is broken, suggesting that hydrodynamic mix has a nontrivial impact on the extent of fast ion losses.« less

Hydrogen isotopes transport parameters in fusion reactor materials

NASA Astrophysics Data System (ADS)

Serra, E.; Benamati, G.; Ogorodnikova, O. V.

1998-06-01

This work presents a review of hydrogen isotopes-materials interactions in various materials of interest for fusion reactors. The relevant parameters cover mainly diffusivity, solubility, trap concentration and energy difference between trap and solution sites. The list of materials includes the martensitic steels (MANET, Batman and F82H-mod.), beryllium, aluminium, beryllium oxide, aluminium oxide, copper, tungsten and molybdenum. Some experimental work on the parameters that describe the surface effects is also mentioned.

Current status and recent research achievements in SiC/SiC composites

NASA Astrophysics Data System (ADS)

Katoh, Y.; Snead, L. L.; Henager, C. H.; Nozawa, T.; Hinoki, T.; Iveković, A.; Novak, S.; Gonzalez de Vicente, S. M.

2014-12-01

The silicon carbide fiber-reinforced silicon carbide matrix (SiC/SiC) composite system for fusion applications has seen a continual evolution from development a fundamental understanding of the material system and its behavior in a hostile irradiation environment to the current effort which is directed at a broad-based program of technology maturation program. In essence, over the past few decades this material system has steadily moved from a laboratory curiosity to an engineering material, both for fusion structural applications and other high performance application such as aerospace. This paper outlines the recent international scientific and technological achievements towards the development of SiC/SiC composite material technologies for fusion application and discusses future research directions. It also reviews the materials system in the larger context of progress to maturity as an engineering material for both the larger nuclear community and broader engineering applications.

Target Fabrication Technology and New Functional Materials for Laser Fusion and Laser-Plasma Experiment

NASA Astrophysics Data System (ADS)

Nagai, Keiji; Norimatsu, Takayoshi; Izawa, Yasukazu

Target fabrication technique is a key issue of laser fusion. We present a comprehensive, up-to-data compilation of laser fusion target fabrication and relating new materials. To achieve highly efficient laser implosion, organic and inorganic highly spherical millimeter-sized capsules and cryogenic hydrogen layers inside should be uniform in diameter and thickness within sub-micrometer ˜ nanometer error. Porous structured targets and molecular cluster targets are required for laser-plasma experiments and applications. Various technologies and new materials concerning above purposes are summarized including fast-ignition targets, equation-of-state measurement targets, high energy ion generation targets, etc.

The materials irradiation experiment for testing plasma facing materials at fusion relevant conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garrison, L. M., E-mail: garrisonlm@ornl.gov; Egle, B. J.; Fusion Technology Institute, University of Wisconsin-Madison, 1500 Engineering Drive, Madison, Wisconsin 53706

2016-08-15

The Materials Irradiation Experiment (MITE-E) was constructed at the University of Wisconsin-Madison Inertial Electrostatic Confinement Laboratory to test materials for potential use as plasma-facing materials (PFMs) in fusion reactors. PFMs in fusion reactors will be bombarded with x-rays, neutrons, and ions of hydrogen and helium. More needs to be understood about the interactions between the plasma and the materials to validate their use for fusion reactors. The MITE-E simulates some of the fusion reactor conditions by holding samples at temperatures up to 1000 °C while irradiating them with helium or deuterium ions with energies from 10 to 150 keV. The ionmore » gun can irradiate the samples with ion currents of 20 μA–500 μA; the typical current used is 72 μA, which is an average flux of 9 × 10{sup 14} ions/(cm{sup 2} s). The ion gun uses electrostatic lenses to extract and shape the ion beam. A variable power (1-20 W), steady-state, Nd:YAG laser provides additional heating to maintain a constant sample temperature during irradiations. The ion beam current reaching the sample is directly measured and monitored in real-time during irradiations. The ion beam profile has been investigated using a copper sample sputtering experiment. The MITE-E has successfully been used to irradiate polycrystalline and single crystal tungsten samples with helium ions and will continue to be a source of important data for plasma interactions with materials.« less

Harnessing Novel Secreted Inhibitors of EGF Receptor Signaling for Breast Cancer Treatment

DTIC Science & Technology

2007-04-01

the original proposal, we described approaches for displaying the basic Argos and Dkk scaffolds as pIII fusions on M13 phage , so that we could...deal of effort into displaying Argos and other relevant proteins as pIII fusions on M13 phage (Task 2a). This has been technically very challenging... display function Argos on the surface of phage M13 , requiring a change in experimental strategy • To replace the phage display , we have established

Atomic Scale Mixing for Inertial Confinement Fusion Associated Hydro Instabilities

DTIC Science & Technology

2013-01-26

observe that the obvious step of RT validation using NIF or Omega laser data does not address themultimode, mode coupling RTgrowth stage, as the...ignition facility, Phys. Plasmas 18 (2011) 051001. [2] W. Goldstein, R. Rosner, Workshop on the Science of Fusion Ignition on NIF , Technical Report LLNL-TR...11 (2004) 339e491. [6] S.P. Regan, R. Epstein, B.A. Hammel, L.J. Suter, J. Ralph, et al., Hot-spot mix in ignition-scale implosions on the NIF , Phys

The choice of the energy embedding law in the design of heavy ionic fusion cylindrical targets

NASA Astrophysics Data System (ADS)

Dolgoleva, GV; Zykova, A. I.

2017-10-01

The paper considers the numerical design of heavy ion fusion (FIHIF) targets, which is one of the branches of controlled thermonuclear fusion (CTF). One of the important tasks in the targets design for controlled thermonuclear fusion is the energy embedding selection whereby it is possible to obtain “burning” (the presence of thermonuclear reactions) of the working DT region. The work is devoted to the rapid ignition of FIHIF targets by means of an additional short-term energy contribution to the DT substance already compressed by massively more longer by energy embedding. This problem has been fairly well studied for laser targets, but this problem is new for heavy ion fusion targets. Maximum momentum increasing is very technically difficult and expensive on modern FIHIF installations. The work shows that the additional energy embedding (“igniting” impulse) reduces the requirements to the maximum impulse. The purpose of this work is to research the ignition impulse effect on the FIHIF target parameters.

Plasma-wall interaction in laser inertial fusion reactors: novel proposals for radiation tests of first wall materials

NASA Astrophysics Data System (ADS)

Alvarez Ruiz, J.; Rivera, A.; Mima, K.; Garoz, D.; Gonzalez-Arrabal, R.; Gordillo, N.; Fuchs, J.; Tanaka, K.; Fernández, I.; Briones, F.; Perlado, J.

2012-12-01

Dry-wall laser inertial fusion (LIF) chambers will have to withstand strong bursts of fast charged particles which will deposit tens of kJ m-2 and implant more than 1018 particles m-2 in a few microseconds at a repetition rate of some Hz. Large chamber dimensions and resistant plasma-facing materials must be combined to guarantee the chamber performance as long as possible under the expected threats: heating, fatigue, cracking, formation of defects, retention of light species, swelling and erosion. Current and novel radiation resistant materials for the first wall need to be validated under realistic conditions. However, at present there is a lack of facilities which can reproduce such ion environments. This contribution proposes the use of ultra-intense lasers and high-intense pulsed ion beams (HIPIB) to recreate the plasma conditions in LIF reactors. By target normal sheath acceleration, ultra-intense lasers can generate very short and energetic ion pulses with a spectral distribution similar to that of the inertial fusion ion bursts, suitable to validate fusion materials and to investigate the barely known propagation of those bursts through background plasmas/gases present in the reactor chamber. HIPIB technologies, initially developed for inertial fusion driver systems, provide huge intensity pulses which meet the irradiation conditions expected in the first wall of LIF chambers and thus can be used for the validation of materials too.

Lithium-based surfaces controlling fusion plasma behavior at the plasma-material interfacea)

NASA Astrophysics Data System (ADS)

Allain, Jean Paul; Taylor, Chase N.

2012-05-01

The plasma-material interface and its impact on the performance of magnetically confined thermonuclear fusion plasmas are considered to be one of the key scientific gaps in the realization of nuclear fusion power. At this interface, high particle and heat flux from the fusion plasma can limit the material's lifetime and reliability and therefore hinder operation of the fusion device. Lithium-based surfaces are now being used in major magnetic confinement fusion devices and have observed profound effects on plasma performance including enhanced confinement, suppression and control of edge localized modes (ELM), lower hydrogen recycling and impurity suppression. The critical spatial scale length of deuterium and helium particle interactions in lithium ranges between 5-100 nm depending on the incident particle energies at the edge and magnetic configuration. Lithium-based surfaces also range from liquid state to solid lithium coatings on a variety of substrates (e.g., graphite, stainless steel, refractory metal W/Mo/etc., or porous metal structures). Temperature-dependent effects from lithium-based surfaces as plasma facing components (PFC) include magnetohydrodynamic (MHD) instability issues related to liquid lithium, surface impurity, and deuterium retention issues, and anomalous physical sputtering increase at temperatures above lithium's melting point. The paper discusses the viability of lithium-based surfaces in future burning-plasma environments such as those found in ITER and DEMO-like fusion reactor devices.

A study of thermal hydraulic and kinetic phenomena in HYLIFE-2: An inertial confinement fusion reactor

NASA Astrophysics Data System (ADS)

Chen, Xiang Ming

1993-01-01

Researchers have studied the different aspects of commercial fusion energy for several decades. A variety of inertial confinement fusion (ICF) reactors have been proposed. Different from the magnetic confinement fusion concept, inertial confinement fusion does not need long-term confinement of the fusion fuel but achieves fusion reaction in a short microexplosion under a high density, high temperature condition. The HYLIFE-2 reactor design started in 1987 is based on the study of a previous concept called HYLIFE (High Yield Lithium Injection Fusion Energy). Similar to the old concept, the HYLIFE-2 design uses a vacuum chamber in which D-T fusion pellets are injected and ignited by high energy beams shot into the reactor through different ports. The reactor vessel is protected from explosion radiations by a liquid fall (blanket) that also breeds tritium through the (n, alpha) reaction of lithium and conveys the fusion energy to the power cycle. In addition to some geometric chances, the new design replaces liquid metal lithium with the molten salt Flibe (Li2BeF4) as the protective blanket material. The objective was to remove the possibility of fire hazard. The important thermal hydraulic issues in the design are (1) equation of state of Flibe; (2) liquid relaxation after isochoric (constant volume) heating; (3) ablation and gas dynamics; (4) interaction of the vapor and liquid; and (5) condensation of the vaporized material. The first four issues have to do with the internal relaxation after the fusion microexplosion in the chamber. Vaporized material, as well as liquid, may assert strong impulses on the chamber wall during the process of relaxing after absorbing the energy from the microexplosion. Item (5) is related to the rapid vacuum recovery between the ignitions. Some aspects of the first four issues are studied.

Progress in magnet design activities for the material plasma exposure experiment

DOE PAGES

Duckworth, Robert; Lumsdaine, Arnold; Rapp, Juergen; ...

2017-07-01

One of the critical challenges for the development of next generation fusion facilities, such as a Fusion Nuclear Science Facility (FNSF) or DEMO, is the understanding of plasma material interactions (PMI). Making progress in PMI research will require integrated facilities that can provide the types of conditions that will be seen in the first wall and divertor regions of future fusion facilities. In order to meet this need, a new linear plasma facility, the Materials Plasma Exposure Experiment (MPEX), is proposed. In order to generate high ion fluence to simulate fusion divertor conditions, a steady-state plasma will be generated andmore » confined with superconducting magnets. Finally, the on-axis fields will range from 1 to 2.5 T in order to meet the requirements of the various plasma source and heating systems. Details on the pre-conceptual design of the magnets and cryogenic system are presented.« less

An accelerated fusion power development plan

NASA Astrophysics Data System (ADS)

Dean, Stephen O.; Baker, Charles C.; Cohn, Daniel R.; Kinkead, Susan D.

1991-06-01

Energy for electricity and transportation is a national issue with worldwide environmental and political implications. The world must have energy options for the next century that are not vulnerable to possible disruption for technical, environmental, public confidence, or other reasons. Growing concerns about the greenhouse effect and the safety of transporting oil may lead to reduced burning of coal and other fossil fuels, and the incidents at Three Mile Island and Chernobyl, as well as nuclear waste storage problems, have eroded public acceptance of nuclear fission. Meeting future world energy needs will require improvements in energy efficiency and conservation. However, the world will soon need new central station power plants and increasing amounts of fuel for the transportation sector. The use of fossil fuels, and possibly even fission power, will very likely be restricted because of environmental, safety, and, eventually, supply considerations. Time is running out for policymakers. New energy technologies cannot be brought to the marketplace overnight. Decades are required to bring a new energy production technology from conception to full market penetration. With the added urgency to mitigate deleterious environmental effects of energy use, policymakers must act decisively now to establish and support vigorous energy technology development programs. The U.S. has invested 8 billion over the past 40 years in fusion research and development. If the U.S. fusion program proceeds according to its present strategy, an additional 40 years, and more money, will be expended before fusion will provide commercial electricity. Such an extended schedule is neither cost-effective nor technically necessary. It is time to launch a national venture to construct and operate a fusion power pilot plant. Such a plant could be operational within 15 years of a national commitment to proceed.

Report on the Installation and Preparedness of a Protochips Fusion in-situ Heating Holder for TEM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edmondson, Philip D.

2017-03-01

This brief report documents the procurement and installation of a Protochips Fusion (formerly Aduro) high-temperature, high stability transmission electron microscopy (TEM) specimen holder that allows for the high spatial resolution characterization of material specimens at high temperature in situ of an electron microscope. This specimen holder was specifically procured for use with The FEI Talos F200X Scanning/Transmission Electron Microscope (STEM) in Oak Ridge National Laboratory’s (ORNL’s) Low Activation Materials Development and Analysis (LAMDA) Laboratory. The Protochips Fusion holder will enable high-resolution structural and chemical analysis of irradiated materials at high temperature, becoming a unique capability worldwide, and would encourage high-qualitymore » in situ experiments to be conducted on irradiated materials.« less

Technical challenges in the construction of the steady-state stellarator Wendelstein 7-X

NASA Astrophysics Data System (ADS)

Bosch, H.-S.; Wolf, R. C.; Andreeva, T.; Baldzuhn, J.; Birus, D.; Bluhm, T.; Bräuer, T.; Braune, H.; Bykov, V.; Cardella, A.; Durodié, F.; Endler, M.; Erckmann, V.; Gantenbein, G.; Hartmann, D.; Hathiramani, D.; Heimann, P.; Heinemann, B.; Hennig, C.; Hirsch, M.; Holtum, D.; Jagielski, J.; Jelonnek, J.; Kasparek, W.; Klinger, T.; König, R.; Kornejew, P.; Kroiss, H.; Krom, J. G.; Kühner, G.; Laqua, H.; Laqua, H. P.; Lechte, C.; Lewerentz, M.; Maier, J.; McNeely, P.; Messiaen, A.; Michel, G.; Ongena, J.; Peacock, A.; Pedersen, T. S.; Riedl, R.; Riemann, H.; Rong, P.; Rust, N.; Schacht, J.; Schauer, F.; Schroeder, R.; Schweer, B.; Spring, A.; Stäbler, A.; Thumm, M.; Turkin, Y.; Wegener, L.; Werner, A.; Zhang, D.; Zilker, M.; Akijama, T.; Alzbutas, R.; Ascasibar, E.; Balden, M.; Banduch, M.; Baylard, Ch.; Behr, W.; Beidler, C.; Benndorf, A.; Bergmann, T.; Biedermann, C.; Bieg, B.; Biel, W.; Borchardt, M.; Borowitz, G.; Borsuk, V.; Bozhenkov, S.; Brakel, R.; Brand, H.; Brown, T.; Brucker, B.; Burhenn, R.; Buscher, K.-P.; Caldwell-Nichols, C.; Cappa, A.; Cardella, A.; Carls, A.; Carvalho, P.; Ciupiński, Ł.; Cole, M.; Collienne, J.; Czarnecka, A.; Czymek, G.; Dammertz, G.; Dhard, C. P.; Davydenko, V. I.; Dinklage, A.; Drevlak, M.; Drotziger, S.; Dudek, A.; Dumortier, P.; Dundulis, G.; Eeten, P. v.; Egorov, K.; Estrada, T.; Faugel, H.; Fellinger, J.; Feng, Y.; Fernandes, H.; Fietz, W. H.; Figacz, W.; Fischer, F.; Fontdecaba, J.; Freund, A.; Funaba, T.; Fünfgelder, H.; Galkowski, A.; Gates, D.; Giannone, L.; García Regaña, J. M.; Geiger, J.; Geißler, S.; Greuner, H.; Grahl, M.; Groß, S.; Grosman, A.; Grote, H.; Grulke, O.; Haas, M.; Haiduk, L.; Hartfuß, H.-J.; Harris, J. H.; Haus, D.; Hein, B.; Heitzenroeder, P.; Helander, P.; Heller, R.; Hidalgo, C.; Hildebrandt, D.; Höhnle, H.; Holtz, A.; Holzhauer, E.; Holzthüm, R.; Huber, A.; Hunger, H.; Hurd, F.; Ihrke, M.; Illy, S.; Ivanov, A.; Jablonski, S.; Jaksic, N.; Jakubowski, M.; Jaspers, R.; Jensen, H.; Jenzsch, H.; Kacmarczyk, J.; Kaliatk, T.; Kallmeyer, J.; Kamionka, U.; Karaleviciu, R.; Kern, S.; Keunecke, M.; Kleiber, R.; Knauer, J.; Koch, R.; Kocsis, G.; Könies, A.; Köppen, M.; Koslowski, R.; Koshurinov, J.; Krämer-Flecken, A.; Krampitz, R.; Kravtsov, Y.; Krychowiak, M.; Krzesinski, G.; Ksiazek, I.; Kubkowska, M.; Kus, A.; Langish, S.; Laube, R.; Laux, M.; Lazerson, S.; Lennartz, M.; Li, C.; Lietzow, R.; Lohs, A.; Lorenz, A.; Louche, F.; Lubyako, L.; Lumsdaine, A.; Lyssoivan, A.; Maaßberg, H.; Marek, P.; Martens, C.; Marushchenko, N.; Mayer, M.; Mendelevitch, B.; Mertens, Ph.; Mikkelsen, D.; Mishchenko, A.; Missal, B.; Mizuuchi, T.; Modrow, H.; Mönnich, T.; Morizaki, T.; Murakami, S.; Musielok, F.; Nagel, M.; Naujoks, D.; Neilson, H.; Neubauer, O.; Neuner, U.; Nocentini, R.; Noterdaeme, J.-M.; Nührenberg, C.; Obermayer, S.; Offermanns, G.; Oosterbeek, H.; Otte, M.; Panin, A.; Pap, M.; Paquay, S.; Pasch, E.; Peng, X.; Petrov, S.; Pilopp, D.; Pirsch, H.; Plaum, B.; Pompon, F.; Povilaitis, M.; Preinhaelter, J.; Prinz, O.; Purps, F.; Rajna, T.; Récsei, S.; Reiman, A.; Reiter, D.; Remmel, J.; Renard, S.; Rhode, V.; Riemann, J.; Rimkevicius, S.; Riße, K.; Rodatos, A.; Rodin, I.; Romé, M.; Roscher, H.-J.; Rummel, K.; Rummel, Th.; Runov, A.; Ryc, L.; Sachtleben, J.; Samartsev, A.; Sanchez, M.; Sano, F.; Scarabosio, A.; Schmid, M.; Schmitz, H.; Schmitz, O.; Schneider, M.; Schneider, W.; Scheibl, L.; Scholz, M.; Schröder, G.; Schröder, M.; Schruff, J.; Schumacher, H.; Shikhovtsev, I. V.; Shoji, M.; Siegl, G.; Skodzik, J.; Smirnow, M.; Speth, E.; Spong, D. A.; Stadler, R.; Sulek, Z.; Szabó, V.; Szabolics, T.; Szetefi, T.; Szökefalvi-Nagy, Z.; Tereshchenko, A.; Thomsen, H.; Thumm, M.; Timmermann, D.; Tittes, H.; Toi, K.; Tournianski, M.; Toussaint, U. v.; Tretter, J.; Tulipán, S.; Turba, P.; Uhlemann, R.; Urban, J.; Urbonavicius, E.; Urlings, P.; Valet, S.; Van Eester, D.; Van Schoor, M.; Vervier, M.; Viebke, H.; Vilbrandt, R.; Vrancken, M.; Wauters, T.; Weissgerber, M.; Weiß, E.; Weller, A.; Wendorf, J.; Wenzel, U.; Windisch, T.; Winkler, E.; Winkler, M.; Wolowski, J.; Wolters, J.; Wrochna, G.; Xanthopoulos, P.; Yamada, H.; Yokoyama, M.; Zacharias, D.; Zajac, J.; Zangl, G.; Zarnstorff, M.; Zeplien, H.; Zoletnik, S.; Zuin, M.

2013-12-01

The next step in the Wendelstein stellarator line is the large superconducting device Wendelstein 7-X, currently under construction in Greifswald, Germany. Steady-state operation is an intrinsic feature of stellarators, and one key element of the Wendelstein 7-X mission is to demonstrate steady-state operation under plasma conditions relevant for a fusion power plant. Steady-state operation of a fusion device, on the one hand, requires the implementation of special technologies, giving rise to technical challenges during the design, fabrication and assembly of such a device. On the other hand, also the physics development of steady-state operation at high plasma performance poses a challenge and careful preparation. The electron cyclotron resonance heating system, diagnostics, experiment control and data acquisition are prepared for plasma operation lasting 30 min. This requires many new technological approaches for plasma heating and diagnostics as well as new concepts for experiment control and data acquisition.

Self-Assembled Materials Made from Functional Recombinant Proteins.

PubMed

Jang, Yeongseon; Champion, Julie A

2016-10-18

Proteins are potent molecules that can be used as therapeutics, sensors, and biocatalysts with many advantages over small-molecule counterparts due to the specificity of their activity based on their amino acid sequence and folded three-dimensional structure. However, they also have significant limitations in their stability, localization, and recovery when used in soluble form. These opportunities and challenges have motivated the creation of materials from such functional proteins in order to protect and present them in a way that enhances their function. We have designed functional recombinant fusion proteins capable of self-assembling into materials with unique structures that maintain or improve the functionality of the protein. Fusion of either a functional protein or an assembly domain to a leucine zipper domain makes the materials design strategy modular, based on the high affinity between leucine zippers. The self-assembly domains, including elastin-like polypeptides (ELPs) and defined-sequence random coil polypeptides, can be fused with a leucine zipper motif in order to promote assembly of the fusion proteins into larger structures upon specific stimuli such as temperature and ionic strength. Fusion of other functional domains with the counterpart leucine zipper motif endows the self-assembled materials with protein-specific functions such as fluorescence or catalytic activity. In this Account, we describe several examples of materials assembled from functional fusion proteins as well as the structural characterization, functionality, and understanding of the assembly mechanism. The first example is zipper fusion proteins containing ELPs that assemble into particles when introduced to a model extracellular matrix and subsequently disassemble over time to release the functional protein for drug delivery applications. Under different conditions, the same fusion proteins can self-assemble into hollow vesicles. The vesicles display a functional protein on the surface and can also carry protein, small-molecule, or nanoparticle cargo in the vesicle lumen. To create a material with a more complex hierarchical structure, we combined calcium phosphate with zipper fusion proteins containing random coil polypeptides to produce hybrid protein-inorganic supraparticles with high surface area and porous structure. The use of a functional enzyme created supraparticles with the ability to degrade inflammatory cytokines. Our characterization of these protein materials revealed that the molecular interactions are complex because of the large size of the protein building blocks, their folded structures, and the number of potential interactions including hydrophobic interactions, electrostatic interactions, van der Waals forces, and specific affinity-based interactions. It is difficult or even impossible to predict the structures a priori. However, once the basic assembly principles are understood, there is opportunity to tune the material properties, such as size, through control of the self-assembly conditions. Our future efforts on the fundamental side will focus on identifying the phase space of self-assembly of these fusion proteins and additional experimental levers with which to control and tune the resulting materials. On the application side, we are investigating an array of different functional proteins to expand the use of these structures in both therapeutic protein delivery and biocatalysis.

Realizing "2001: A Space Odyssey": Piloted Spherical Torus Nuclear Fusion Propulsion

NASA Technical Reports Server (NTRS)

Williams, Craig H.; Dudzinski, Leonard A.; Borowski, Stanley K.; Juhasz, Albert J.

2005-01-01

A conceptual vehicle design enabling fast, piloted outer solar system travel was created predicated on a small aspect ratio spherical torus nuclear fusion reactor. The initial requirements were satisfied by the vehicle concept, which could deliver a 172 mt crew payload from Earth to Jupiter rendezvous in 118 days, with an initial mass in low Earth orbit of 1,690 mt. Engineering conceptual design, analysis, and assessment was performed on all major systems including artificial gravity payload, central truss, nuclear fusion reactor, power conversion, magnetic nozzle, fast wave plasma heating, tankage, fuel pellet injector, startup/re-start fission reactor and battery bank, refrigeration, reaction control, communications, mission design, and space operations. Detailed fusion reactor design included analysis of plasma characteristics, power balance/utilization, first wall, toroidal field coils, heat transfer, and neutron/x-ray radiation. Technical comparisons are made between the vehicle concept and the interplanetary spacecraft depicted in the motion picture 2001: A Space Odyssey.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neilson, Hutch

Nuclear fusion — the process that powers the sun — offers an environmentally benign, intrinsically safe energy source with an abundant supply of low-cost fuel. It is the focus of an international research program, including the ITER fusion collaboration, which involves seven parties representing half the world’s population. The realization of fusion power would change the economics and ecology of energy production as profoundly as petroleum exploitation did two centuries ago. The 21st century finds fusion research in a transformed landscape. The worldwide fusion community broadly agrees that the science has advanced to the point where an aggressive action plan,more » aimed at the remaining barriers to practical fusion energy, is warranted. At the same time, and largely because of its scientific advance, the program faces new challenges; above all it is challenged to demonstrate the timeliness of its promised benefits. In response to this changed landscape, the Office of Fusion Energy Sciences (OFES) in the US Department of Energy commissioned a number of community-based studies of the key scientific and technical foci of magnetic fusion research. The Research Needs Workshop (ReNeW) for Magnetic Fusion Energy Sciences is a capstone to these studies. In the context of magnetic fusion energy, ReNeW surveyed the issues identified in previous studies, and used them as a starting point to define and characterize the research activities that the advance of fusion as a practical energy source will require. Thus, ReNeW’s task was to identify (1) the scientific and technological research frontiers of the fusion program, and, especially, (2) a set of activities that will most effectively advance those frontiers. (Note that ReNeW was not charged with developing a strategic plan or timeline for the implementation of fusion power.)« less

The value of materials R&D in the fast track development of fusion power

NASA Astrophysics Data System (ADS)

Ward, D. J.; Taylor, N. P.; Cook, I.

2007-08-01

The objective of the international fusion program is the creation of power plants with attractive safety and environmental features and viable economics. There is a range of possible plants that can meet these objectives, as studied for instance in the recent EU studies of power plant concepts. All of the concepts satisfy safety and environmental objectives but the economic performance is interpreted differently in different world regions according to the perception of future energy markets. This leads to different materials performance targets and the direction and timescales of the materials development programme needed to meet those targets. In this paper, the implications for materials requirements of a fast track approach to fusion development are investigated. This includes a quantification of the overall benefits of more advanced materials: including the effect of trading off an extended development time against a reduced cost of electricity for resulting power plants.

STATs and macrophage fusion.

PubMed

Miyamoto, Takeshi

2013-07-01

Macrophages play a pivotal role in host defense against multiple foreign materials such as bacteria, parasites and artificial devices. Some macrophage lineage cells, namely osteoclasts and foreign body giant cells (FBGCs), form multi-nuclear giant cells by the cell-cell fusion of mono-nuclear cells. Osteoclasts are bone-resorbing cells, and are formed in the presence of RANKL on the surface of bones, while FBGCs are formed in the presence of IL-4 or IL-13 on foreign materials such as artificial joints, catheters and parasites. Recently, fusiogenic mechanisms and the molecules required for the cell-cell fusion of these macrophage lineage cells were, at least in part, clarified. Dendritic cell specific transmembrane protein (DC-STAMP) and osteoclast stimulatory transmembrane protein (OC-STAMP), both of which comprise seven transmembrane domains, are required for both osteoclast and FBGC cell-cell fusion. STAT6 was demonstrated to be required for the cell-cell fusion of FBGCs but not osteoclasts. In this review, advances in macrophage cell-cell fusion are discussed.

Void migration in fusion materials

NASA Astrophysics Data System (ADS)

Cottrell, G. A.

2002-04-01

Neutron irradiation in a fusion power plant will cause helium bubbles and voids to form in the armour and blanket structural materials. If sufficiently large densities of such defects accumulate on the grain boundaries of the materials, the strength and the lifetimes of the metals will be reduced by helium embrittlement and grain boundary failure. This Letter discusses void migration in metals, both by random Brownian motion and by biassed flow in temperature gradients. In the assumed five-year blanket replacement time of a fusion power plant, approximate calculations show that the metals most resilient to failure are tungsten and molybdenum, and marginally vanadium. Helium embrittlement and grain boundary failure is expected to be more severe in steel and beryllium.

Apparatus and method for simulating material damage from a fusion reactor

DOEpatents

Smith, Dale L.; Greenwood, Lawrence R.; Loomis, Benny A.

1989-01-01

An apparatus and method for simulating a fusion environment on a first wall or blanket structure. A material test specimen is contained in a capsule made of a material having a low hydrogen solubility and permeability. The capsule is partially filled with a lithium solution, such that the test specimen is encapsulated by the lithium. The capsule is irradiated by a fast fission neutron source.

Apparatus and method for simulating material damage from a fusion reactor

DOEpatents

Smith, D.L.; Greenwood, L.R.; Loomis, B.A.

1988-05-20

This paper discusses an apparatus and method for simulating a fusion environment on a first wall or blanket structure. A material test specimen is contained in a capsule made of a material having a low hydrogen solubility and permeability. The capsule is partially filled with a lithium solution, such that the test specimen is encapsulated by the lithium. The capsule is irradiated by a fast fission neutron source.

Apparatus and method for simulating material damage from a fusion reactor

DOEpatents

Smith, Dale L.; Greenwood, Lawrence R.; Loomis, Benny A.

1989-03-07

An apparatus and method for simulating a fusion environment on a first wall or blanket structure. A material test specimen is contained in a capsule made of a material having a low hydrogen solubility and permeability. The capsule is partially filled with a lithium solution, such that the test specimen is encapsulated by the lithium. The capsule is irradiated by a fast fission neutron source.

Application of Resorbable Poly(Lactide-co-Glycolide) with Entangled Hyaluronic Acid as an Autograft Extender for Posterolateral Intertransverse Lumbar Fusion in Rabbits

PubMed Central

Oliver, Rema A.; Gage, Gary; Yu, Yan; Bell, David; Bellemore, Jeremy; Adkisson, Huston Davis

2011-01-01

Facilitating fusion between bony segments in a reliable and reproducible manner using a synthetic bone graft material has a number of benefits for the surgeon as well as the patient. Although autograft remains the gold standard, associated comorbidities continue to drive the development of new biomaterials for use in spinal fusion. The ability of autograft alone and autograft combined with a radiolucent biomaterial composed of resorbable osteoconductive poly(lactide-co-glycolide) with entangled hyaluronic acid to facilitate fusion was examined in a single-level noninstrumented posterolateral intertransverse lumbar fusion model in New Zealand White rabbits. Progressive bone formation was demonstrated radiographically for the extender group (synthetic biomaterial plus autograft) between 3 and 6 months. Computed tomography revealed a new cortical shell in the fusion mass at 3 and 6 months for both study groups. Tensile testing at 6 months demonstrated that the quality of bone formed between the intertransverse space was equivalent for both study groups. Histologic evaluation of the fusion mass revealed new bone on and adjacent to the transverse processes with the synthetic biomaterial group that extended laterally, supporting the osteoconductive nature of the material. Histological evidence of endochondral bone growth in the intertransverse space was observed for the autograft plus synthetic biomaterial group. Bone remodeling, new marrow spaces, and peripheral cortices were observed for each study group at 3 months that matured by 6 months. These findings support the use of a radiolucent biosynthetic material comprising poly(lactide-co-glycolide) with integrated hyaluronic acid as an autograft extender for lumbar intertransverse fusion. PMID:20712417

ACDF Graft Selection by Surgeons: Survey of AOSpine Members.

PubMed

Yoon, S Tim; Konopka, Jeffrey A; Wang, Jeffrey C; Youssef, Jim A; Meisel, Hans Joerg; Brodke, Darrel S; Park, Jong-Beom

2017-08-01

Cross-sectional survey study. To determine what are the most commonly used graft materials in anterior cervical discectomy and fusion and whether the choice of graft is affected by surgeon's training, years in practice, geographic location, practice setting, or surgeon's perceived difficulty in achieving fusion. A 23-question survey was sent out to 5334 surgeons using the Global AO Spine database. Response data was then stratified into surgeon training, years of practice, practice type, and global region. Overall, surgeons believe that graft selection affects fusion rates (89.3% of surgeons) and affects time to fusion (86.0% of surgeons). The use of a cage is currently the most common structural graft component used worldwide at 64.1%. Of surgeons that use cages, the PEEK Cage makes up 84%. North American surgeons differ from this global trend and use composite allograft more commonly. The choice to add a nonstructural graft component was reported at 74%. This result was similar for performing multilevel fusions at 72.8%. The selection of nonstructural graft material depends on whether the type of surgery is considered simple or complex. Most surgeons are not satisfied with available literature comparing effectiveness of grafts but believed that there was sufficient evidence to support the use of their chosen graft. Almost all surgeons believe that fusion is important to anterior cervical discectomy and fusion surgery outcomes and that most surgeons believe graft choice affects fusion. However, this survey indicates that there is great variability in the type of graft material used by spine surgeons across the world.

Thick Nano-Crystalline Diamond films for fusion applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dawedeit, Christoph

This Diplomarbeit deals with the characterization of 9 differently grown diamond samples. Several techniques were used to determine the quality of these specimens for inertial confinement fusion targets. The quality of chemical vapor deposition diamond is usually considered in terms of the proportion of sp3-bonded carbon to sp2-bonded carbon in the sample. For fusion targets smoothness, Hydrogen content and density of the diamonds are further important characteristics. These characteristics are analyzed in this thesis. The research for thesis was done at Lawrence Livermore National Laboratory in collaboration with the Fraunhofer Institut für angewandte Festkörperphysik Freiburg, Germany. Additionally the Lehrstuhl fuermore » Nukleartechnik at Technical University of Germany supported the work.« less

Space fusion energy conversion using a field reversed configuration reactor: A new technical approach for space propulsion and power

NASA Technical Reports Server (NTRS)

Schulze, Norman R.; Miley, George H.; Santarius, John F.

1991-01-01

The fusion energy conversion design approach, the Field Reversed Configuration (FRC) - when burning deuterium and helium-3, offers a new method and concept for space transportation with high energy demanding programs, like the Manned Mars Mission and planetary science outpost missions require. FRC's will increase safety, reduce costs, and enable new missions by providing a high specific power propulsion system from a high performance fusion engine system that can be optimally designed. By using spacecraft powered by FRC's the space program can fulfill High Energy Space Missions (HESM) in a manner not otherwise possible. FRC's can potentially enable the attainment of high payload mass fractions while doing so within shorter flight times.

Feasibility of three-dimensional magnetic resonance angiography-fluoroscopy image fusion technique in guiding complex endovascular aortic procedures in patients with renal insufficiency.

PubMed

Schwein, Adeline; Chinnadurai, Ponraj; Shah, Dipan J; Lumsden, Alan B; Bechara, Carlos F; Bismuth, Jean

2017-05-01

Three-dimensional image fusion of preoperative computed tomography (CT) angiography with fluoroscopy using intraoperative noncontrast cone-beam CT (CBCT) has been shown to improve endovascular procedures by reducing procedure length, radiation dose, and contrast media volume. However, patients with a contraindication to CT angiography (renal insufficiency, iodinated contrast allergy) may not benefit from this image fusion technique. The primary objective of this study was to evaluate the feasibility of magnetic resonance angiography (MRA) and fluoroscopy image fusion using noncontrast CBCT as a guidance tool during complex endovascular aortic procedures, especially in patients with renal insufficiency. All endovascular aortic procedures done under MRA image fusion guidance at a single-center were retrospectively reviewed. The patients had moderate to severe renal insufficiency and underwent diagnostic contrast-enhanced magnetic resonance imaging after gadolinium or ferumoxytol injection. Relevant vascular landmarks electronically marked in MRA images were overlaid on real-time two-dimensional fluoroscopy for image guidance, after image fusion with noncontrast intraoperative CBCT. Technical success, time for image registration, procedure time, fluoroscopy time, number of digital subtraction angiography (DSA) acquisitions before stent deployment or vessel catheterization, and renal function before and after the procedure were recorded. The image fusion accuracy was qualitatively evaluated on a binary scale by three physicians after review of image data showing virtual landmarks from MRA on fluoroscopy. Between November 2012 and March 2016, 10 patients underwent endovascular procedures for aortoiliac aneurysmal disease or aortic dissection using MRA image fusion guidance. All procedures were technically successful. A paired t-test analysis showed no difference between preimaging and postoperative renal function (P = .6). The mean time required for MRA-CBCT image fusion was 4:09 ± 01:31 min:sec. Total fluoroscopy time was 20.1 ± 6.9 minutes. Five of 10 patients (50%) underwent stent graft deployment without any predeployment DSA acquisition. Three of six vessels (50%) were cannulated under image fusion guidance without any precannulation DSA runs, and the remaining vessels were cannulated after one planning DSA acquisition. Qualitative evaluation showed 14 of 22 virtual landmarks (63.6%) from MRA overlaid on fluoroscopy were completely accurate, without the need for adjustment. Five of eight incorrect virtual landmarks (iliac and visceral arteries) resulted from vessel deformation caused by endovascular devices. Ferumoxytol or gadolinium-enhanced MRA imaging and image fusion with fluoroscopy using noncontrast CBCT is feasible and allows patients with renal insufficiency to benefit from optimal guidance during complex endovascular aortic procedures, while preserving their residual renal function. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Rapid Method for Sodium Hydroxide Fusion of Asphalt ...

EPA Pesticide Factsheets

Technical Brief--Addendum to Selected Analytical Methods (SAM) 2012 The method will be used for qualitative analysis of americium-241, plutonium-238, plutonium-239, radium-226, strontium-90, uranium-234, uranium-235 and uranium-238 in asphalt matrices samples.

Cellular bone matrices: viable stem cell-containing bone graft substitutes

PubMed Central

Skovrlj, Branko; Guzman, Javier Z.; Al Maaieh, Motasem; Cho, Samuel K.; Iatridis, James C.; Qureshi, Sheeraz A.

2015-01-01

BACKGROUND CONTEXT Advances in the field of stem cell technology have stimulated the development and increased use of allogenic bone grafts containing live mesenchymal stem cells (MSCs), also known as cellular bone matrices (CBMs). It is estimated that CBMs comprise greater than 17% of all bone grafts and bone graft substitutes used. PURPOSE To critically evaluate CBMs, specifically their technical specifications, existing published data supporting their use, US Food and Drug Administration (FDA) regulation, cost, potential pitfalls, and other aspects pertaining to their use. STUDY DESIGN Areview of literature. METHODS A series of Ovid, Medline, and Pubmed-National Library of Medicine/National Institutes of Health (www.ncbi.nlm.nih.gov) searches were performed. Only articles in English journals or published with English language translations were included. Level of evidence of the selected articles was assessed. Specific technical information on each CBM was obtained by direct communication from the companies marketing the individual products. RESULTS Five different CBMs are currently available for use in spinal fusion surgery. There is a wide variation between the products with regard to the average donor age at harvest, total cellular concentration, percentage of MSCs, shelf life, and cell viability after defrosting. Three retrospective studies evaluating CBMs and fusion have shown fusion rates ranging from 90.2% to 92.3%, and multiple industry-sponsored trials are underway. No independent studies evaluating spinal fusion rates with the use of CBMs exist. All the commercially available CBMs claim to meet the FDA criteria under Section 361, 21 CFR Part 1271, and are not undergoing FDA premarket review. The CBMs claim to provide viable MSCs and are offered at a premium cost. Numerous challenges exist in regard to MSCs’ survival, function, osteoblastic potential, and cytokine production once implanted into the intended host. CONCLUSIONS Cellular bone matrices may be a promising bone augmentation technology in spinal fusion surgery. Although CBMs appear to be safe for use as bone graft substitutes, their efficacy in spinal fusion surgery remains highly inconclusive. Large, nonindustry sponsored studies evaluating the efficacy of CBMs are required. Without results from such studies, surgeons must be made aware of the potential pitfalls of CBMs in spinal fusion surgery. With the currently available data, there is insufficient evidence to support the use of CBMs as bone graft substitutes in spinal fusion surgery. PMID:24929059

Cellular bone matrices: viable stem cell-containing bone graft substitutes.

PubMed

Skovrlj, Branko; Guzman, Javier Z; Al Maaieh, Motasem; Cho, Samuel K; Iatridis, James C; Qureshi, Sheeraz A

2014-11-01

Advances in the field of stem cell technology have stimulated the development and increased use of allogenic bone grafts containing live mesenchymal stem cells (MSCs), also known as cellular bone matrices (CBMs). It is estimated that CBMs comprise greater than 17% of all bone grafts and bone graft substitutes used. To critically evaluate CBMs, specifically their technical specifications, existing published data supporting their use, US Food and Drug Administration (FDA) regulation, cost, potential pitfalls, and other aspects pertaining to their use. Areview of literature. A series of Ovid, Medline, and Pubmed-National Library of Medicine/National Institutes of Health (www.ncbi.nlm.nih.gov) searches were performed. Only articles in English journals or published with English language translations were included. Level of evidence of the selected articles was assessed. Specific technical information on each CBM was obtained by direct communication from the companies marketing the individual products. Five different CBMs are currently available for use in spinal fusion surgery. There is a wide variation between the products with regard to the average donor age at harvest, total cellular concentration, percentage of MSCs, shelf life, and cell viability after defrosting. Three retrospective studies evaluating CBMs and fusion have shown fusion rates ranging from 90.2% to 92.3%, and multiple industry-sponsored trials are underway. No independent studies evaluating spinal fusion rates with the use of CBMs exist. All the commercially available CBMs claim to meet the FDA criteria under Section 361, 21 CFR Part 1271, and are not undergoing FDA premarket review. The CBMs claim to provide viable MSCs and are offered at a premium cost. Numerous challenges exist in regard to MSCs' survival, function, osteoblastic potential, and cytokine production once implanted into the intended host. Cellular bone matrices may be a promising bone augmentation technology in spinal fusion surgery. Although CBMs appear to be safe for use as bone graft substitutes, their efficacy in spinal fusion surgery remains highly inconclusive. Large, nonindustry sponsored studies evaluating the efficacy of CBMs are required. Without results from such studies, surgeons must be made aware of the potential pitfalls of CBMs in spinal fusion surgery. With the currently available data, there is insufficient evidence to support the use of CBMs as bone graft substitutes in spinal fusion surgery. Copyright © 2014 Elsevier Inc. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

Nuclear fusion - the process that powers the sun - offers an environmentally benign, intrinsically safe energy source with an abundant supply of low-cost fuel. It is the focus of an international research program, including the ITE R fusion collaboration, which involves seven parties representing half the world's population. The realization of fusion power would change the economics and ecology of energy production as profoundly as petroleum exploitation did two centuries ago. The 21st century finds fusion research in a transformed landscape. The worldwide fusion community broadly agrees that the science has advanced to the point where an aggressive actionmore » plan, aimed at the remaining barriers to practical fusion energy, is warranted. At the same time, and largely because of its scientific advance, the program faces new challenges; above all it is challenged to demonstrate the timeliness of its promised benefits. In response to this changed landscape, the Office of Fusion Energy Sciences (OFES ) in the US Department of Energy commissioned a number of community-based studies of the key scientific and technical foci of magnetic fusion research. The Research Needs Workshop (ReNeW) for Magnetic Fusion Energy Sciences is a capstone to these studies. In the context of magnetic fusion energy, ReNeW surveyed the issues identified in previous studies, and used them as a starting point to define and characterize the research activities that the advance of fusion as a practical energy source will require. Thus, ReNeW's task was to identify (1) the scientific and technological research frontiers of the fusion program, and, especially, (2) a set of activities that will most effectively advance those frontiers. (Note that ReNeW was not charged with developing a strategic plan or timeline for the implementation of fusion power.) This Report presents a portfolio of research activities for US research in magnetic fusion for the next two decades. It is intended to provide a strategic framework for realizing practical fusion energy. The portfolio is the product of ten months of fusion-community study and discussion, culminating in a Workshop held in Bethesda, Maryland, from June 8 to June 12, 2009. The Workshop involved some 200 scientists from Universities, National Laboratories and private industry, including several scientists from outside the US. Largely following the Basic Research Needs model established by the Office of Basic Energy Sciences (BES ), the Report presents a collection of discrete research activities, here called 'thrusts.' Each thrust is based on an explicitly identified question, or coherent set of questions, on the frontier of fusion science. It presents a strategy to find the needed answers, combining the necessary intellectual and hardware tools, experimental facilities, and computational resources into an integrated, focused program. The thrusts should be viewed as building blocks for a fusion program plan whose overall structure will be developed by OFES , using whatever additional community input it requests. Part I of the Report reviews the issues identified in previous fusion-community studies, which systematically identified the key research issues and described them in considerable detail. It then considers in some detail the scientific and technical means that can be used to address these is sues. It ends by showing how these various research requirements are organized into a set of eighteen thrusts. Part II presents a detailed and self-contained discussion of each thrust, including the goals, required facilities and tools for each. This Executive Summary focuses on a survey of the ReNeW thrusts. The following brief review of fusion science is intended to provide context for that survey. A more detailed discussion of fusion science can be found in an Appendix to this Summary, entitled 'A Fusion Primer.'« less

A Standard Mammography Unit - Standard 3D Ultrasound Probe Fusion Prototype: First Results.

PubMed

Schulz-Wendtland, Rüdiger; Jud, Sebastian M; Fasching, Peter A; Hartmann, Arndt; Radicke, Marcus; Rauh, Claudia; Uder, Michael; Wunderle, Marius; Gass, Paul; Langemann, Hanna; Beckmann, Matthias W; Emons, Julius

2017-06-01

The combination of different imaging modalities through the use of fusion devices promises significant diagnostic improvement for breast pathology. The aim of this study was to evaluate image quality and clinical feasibility of a prototype fusion device (fusion prototype) constructed from a standard tomosynthesis mammography unit and a standard 3D ultrasound probe using a new method of breast compression. Imaging was performed on 5 mastectomy specimens from patients with confirmed DCIS or invasive carcinoma (BI-RADS ™ 6). For the preclinical fusion prototype an ABVS system ultrasound probe from an Acuson S2000 was integrated into a MAMMOMAT Inspiration (both Siemens Healthcare Ltd) and, with the aid of a newly developed compression plate, digital mammogram and automated 3D ultrasound images were obtained. The quality of digital mammogram images produced by the fusion prototype was comparable to those produced using conventional compression. The newly developed compression plate did not influence the applied x-ray dose. The method was not more labour intensive or time-consuming than conventional mammography. From the technical perspective, fusion of the two modalities was achievable. In this study, using only a few mastectomy specimens, the fusion of an automated 3D ultrasound machine with a standard mammography unit delivered images of comparable quality to conventional mammography. The device allows simultaneous ultrasound - the second important imaging modality in complementary breast diagnostics - without increasing examination time or requiring additional staff.

LIFE Materials: Thermomechanical Effects Volume 5 - Part I

DOE Office of Scientific and Technical Information (OSTI.GOV)

Caro, M; DeMange, P; Marian, J

2009-05-07

Improved fuel performance is a key issue in the current Laser Inertial-Confinement Fusion-Fission Energy (LIFE) engine design. LIFE is a fusion-fission engine composed of a {approx}40-tons fuel blanket surrounding a pulsed fusion neutron source. Fusion neutrons get multiplied and moderated in a Beryllium blanket before penetrating the subcritical fission blanket. The fuel in the blanket is composed of millions of fuel pebbles, and can in principle be burned to over 99% FIMA without refueling or reprocessing. This report contains the following chapters: Chapter A: LIFE Requirements for Materials -- LIFE Fuel; Chapter B: Summary of Existing Knowledge; Chapter C: Identificationmore » of Gaps in Knowledge & Vulnerabilities; and Chapter D: Strategy and Future Work.« less

Fission and activation of uranium by fusion-plasma neutrons

NASA Technical Reports Server (NTRS)

Lee, J. H.; Hohl, F.; Mcfarland, D. R.

1978-01-01

Fusion-fission hybrid reactors are discussed in terms of two main purposes: to breed fissile materials (Pu 233 and Th 233 from U 238 or Th 232) for use in low-reactivity breeders, and to produce tritium from lithium to refuel fusion plasma cores. Neutron flux generation is critical for both processes. Various methods for generating the flux are described, with attention to new geometries for multiple plasma focus arrays, e.g., hypocycloidal pinch and staged plasma focus devices. These methods are evaluated with reference to their applicability to D-D fusion reactors, which will ensure a virtually unlimited energy supply. Accurate observations of the neutron flux from such schemes are obtained by using different target materials in the plasma focus.

The history of head transplantation: a review.

PubMed

Lamba, Nayan; Holsgrove, Daniel; Broekman, Marike L

2016-12-01

Since the turn of the last century, the prospect of head transplantation has captured the imagination of scientists and the general public. Recently, head transplant has regained attention in popular media, as neurosurgeons have proposed performing this procedure in 2017. Given the potential impact of such a procedure, we were interested in learning the history of the technical hurdles that need to be overcome, and determine if it is even technically possible to perform such a procedure on humans today. We conducted a historical review of available literature on the technical challenges and developments of head transplantation. The many social, psychological, ethical, religious, cultural, and legal questions of head transplantation were beyond the scope of this review. Our historical review identified the following important technical considerations related to performing a head transplant: maintenance of blood flow to an isolated brain via vessel anastomosis; availability of immunosuppressive agents; spinal anastomosis and fusion following cord transfection; pain control in the recipient. Several animal studies have demonstrated success in maintaining recipient cerebral perfusion and achieving immunosuppression. However, there is currently sparse evidence in favor of successful spinal anastomosis and fusion after transection. While recent publications by an Italian group offer novel approaches to this challenge, research on this topic has been sparse and hinges on procedures performed in animal models in the 1970s. How transferrable these older methods are to the human nervous system is unclear and warrants further exploration. Our review identified several important considerations related to performing a viable head transplantation. Besides the technical challenges that remain, there are important ethical issues to consider, such as exploitation of vulnerable patients and informed consent. Thus, besides the remaining technical challenges, these ethical issues will also need to be addressed before moving these studies to the clinic.

Proceedings of the magnetic fusion energy blanket and shield workshop. A technical assessment. Volume I

DOE Office of Scientific and Technical Information (OSTI.GOV)

Powell, J.R.; Fillo, J.A.; Twining, B.G.

1975-08-01

The first volume of these Proceedings is devoted to summarizing the results of the activities of the five technical area Study Groups. These Study Groups played a major role in the Workshop since it was their mission to identify key research and development requirements in their technical areas, etimate the prospects for success of research and development projects directed toward fulfilling these requirements, and determine appropriate time scales for the initiation and completion of these efforts. The determination of which new scientific and technological knowledge, data, and techniques will be required to achieve the Division of Magnetic Fusion Energy programmore » goals, and the construction of an evaluated compilation of research and development needs along with suggestions for levels of effort needed to achieve these goals were among the objectives of the Study Groups. The Conclusions and Recommendations of the Study Groups are summaries of the individual Study Group's findings prepared by the chairmen and co-chairmen/secretaries. These findings were presented to all the Workshop participants in a plenary session, and the discussion and comments on the findings are included in this volume.« less

Application of Multimodality Imaging Fusion Technology in Diagnosis and Treatment of Malignant Tumors under the Precision Medicine Plan.

PubMed

Wang, Shun-Yi; Chen, Xian-Xia; Li, Yi; Zhang, Yu-Ying

2016-12-20

The arrival of precision medicine plan brings new opportunities and challenges for patients undergoing precision diagnosis and treatment of malignant tumors. With the development of medical imaging, information on different modality imaging can be integrated and comprehensively analyzed by imaging fusion system. This review aimed to update the application of multimodality imaging fusion technology in the precise diagnosis and treatment of malignant tumors under the precision medicine plan. We introduced several multimodality imaging fusion technologies and their application to the diagnosis and treatment of malignant tumors in clinical practice. The data cited in this review were obtained mainly from the PubMed database from 1996 to 2016, using the keywords of "precision medicine", "fusion imaging", "multimodality", and "tumor diagnosis and treatment". Original articles, clinical practice, reviews, and other relevant literatures published in English were reviewed. Papers focusing on precision medicine, fusion imaging, multimodality, and tumor diagnosis and treatment were selected. Duplicated papers were excluded. Multimodality imaging fusion technology plays an important role in tumor diagnosis and treatment under the precision medicine plan, such as accurate location, qualitative diagnosis, tumor staging, treatment plan design, and real-time intraoperative monitoring. Multimodality imaging fusion systems could provide more imaging information of tumors from different dimensions and angles, thereby offing strong technical support for the implementation of precision oncology. Under the precision medicine plan, personalized treatment of tumors is a distinct possibility. We believe that multimodality imaging fusion technology will find an increasingly wide application in clinical practice.

Affordable non-traditional source data mining for context assessment to improve distributed fusion system robustness

NASA Astrophysics Data System (ADS)

Bowman, Christopher; Haith, Gary; Steinberg, Alan; Morefield, Charles; Morefield, Michael

2013-05-01

This paper describes methods to affordably improve the robustness of distributed fusion systems by opportunistically leveraging non-traditional data sources. Adaptive methods help find relevant data, create models, and characterize the model quality. These methods also can measure the conformity of this non-traditional data with fusion system products including situation modeling and mission impact prediction. Non-traditional data can improve the quantity, quality, availability, timeliness, and diversity of the baseline fusion system sources and therefore can improve prediction and estimation accuracy and robustness at all levels of fusion. Techniques are described that automatically learn to characterize and search non-traditional contextual data to enable operators integrate the data with the high-level fusion systems and ontologies. These techniques apply the extension of the Data Fusion & Resource Management Dual Node Network (DNN) technical architecture at Level 4. The DNN architecture supports effectively assessment and management of the expanded portfolio of data sources, entities of interest, models, and algorithms including data pattern discovery and context conformity. Affordable model-driven and data-driven data mining methods to discover unknown models from non-traditional and `big data' sources are used to automatically learn entity behaviors and correlations with fusion products, [14 and 15]. This paper describes our context assessment software development, and the demonstration of context assessment of non-traditional data to compare to an intelligence surveillance and reconnaissance fusion product based upon an IED POIs workflow.

DOE Office of Scientific and Technical Information (OSTI.GOV)

R. Strykowsky, T. Brown, J. Chrzanowski, M. Cole, P. Heitzenroeder, G.H. Neilson, Donald Rej, and M. Viola

The National Compact Stellarator Experiment (NCSX) was designed to test physics principles of an innovative fusion energy confinement device developed by the Princeton Plasma Physics Laboratory (PPPL) and Oak Ridge National Laboratory (ORNL) under contract from the US Department of Energy. The project was technically very challenging, primarily due to the complex component geometries and tight tolerances that were required. As the project matured these challenges manifested themselves in significant cost overruns through all phases of the project (i.e. design, R&D, fabrication and assembly). The project was subsequently cancelled by the DOE in 2008. Although the project was not completed,more » several major work packages, comprising about 65% of the total estimated cost (excluding management and contingency), were completed, providing a data base of actual costs that can be analyzed to understand cost drivers. Technical factors that drove costs included the complex geometry, tight tolerances, material requirements, and performance requirements. Management factors included imposed annual funding constraints that throttled project cash flow, staff availability, and inadequate R&D. Understanding how requirements and design decisions drove cost through this top-down forensic cost analysis could provide valuable insight into the configuration and design of future state-of-the art machines and other devices.« less

Progress in Mirror-Based Fusion Neutron Source Development.

PubMed

Anikeev, A V; Bagryansky, P A; Beklemishev, A D; Ivanov, A A; Kolesnikov, E Yu; Korzhavina, M S; Korobeinikova, O A; Lizunov, A A; Maximov, V V; Murakhtin, S V; Pinzhenin, E I; Prikhodko, V V; Soldatkina, E I; Solomakhin, A L; Tsidulko, Yu A; Yakovlev, D V; Yurov, D V

2015-12-04

The Budker Institute of Nuclear Physics in worldwide collaboration has developed a project of a 14 MeV neutron source for fusion material studies and other applications. The projected neutron source of the plasma type is based on the gas dynamic trap (GDT), which is a special magnetic mirror system for plasma confinement. Essential progress in plasma parameters has been achieved in recent experiments at the GDT facility in the Budker Institute, which is a hydrogen (deuterium) prototype of the source. Stable confinement of hot-ion plasmas with the relative pressure exceeding 0.5 was demonstrated. The electron temperature was increased up to 0.9 keV in the regime with additional electron cyclotron resonance heating (ECRH) of a moderate power. These parameters are the record for axisymmetric open mirror traps. These achievements elevate the projects of a GDT-based neutron source on a higher level of competitive ability and make it possible to construct a source with parameters suitable for materials testing today. The paper presents the progress in experimental studies and numerical simulations of the mirror-based fusion neutron source and its possible applications including a fusion material test facility and a fusion-fission hybrid system.

Biomechanical Evaluation of a Novel Apatite-Wollastonite Ceramic Cage Design for Lumbar Interbody Fusion: A Finite Element Model Study

PubMed Central

Şenköylü, Alpaslan; Aktaş, Erdem; Sarıkaya, Baran; Sipahioğlu, Serkan; Gürbüz, Rıza; Timuçin, Muharrem

2018-01-01

Objectives Cage design and material properties play a crucial role in the long-term results, since interbody fusions using intervertebral cages have become one of the basic procedures in spinal surgery. Our aim is to design a novel Apatite-Wollastonite interbody fusion cage and evaluate its biomechanical behavior in silico in a segmental spinal model. Materials and Methods Mechanical properties for the Apatite-Wollastonite bioceramic cages were obtained by fitting finite element results to the experimental compression behavior of a cage prototype. The prototype was made from hydroxyapatite, pseudowollastonite, and frit by sintering. The elastic modulus of the material was found to be 32 GPa. Three intact lumbar vertebral segments were modelled with the ANSYS 12.0.1 software and this model was modified to simulate a Posterior Lumbar Interbody Fusion. Four cage designs in different geometries were analyzed in silico under axial loading, flexion, extension, and lateral bending. Results The K2 design had the best overall biomechanical performance for the loads considered. Maximum cage stress recorded was 36.7 MPa in compression after a flexion load, which was within the biomechanical limits of the cage. Conclusion Biomechanical analyses suggest that K2 bioceramic cage is an optimal design and reveals essential material properties for a stable interbody fusion. PMID:29581974

Fusion neutron source blanket: requirements for calculation accuracy and benchmark experiment precision

NASA Astrophysics Data System (ADS)

Zhirkin, A. V.; Alekseev, P. N.; Batyaev, V. F.; Gurevich, M. I.; Dudnikov, A. A.; Kuteev, B. V.; Pavlov, K. V.; Titarenko, Yu. E.; Titarenko, A. Yu.

2017-06-01

In this report the calculation accuracy requirements of the main parameters of the fusion neutron source, and the thermonuclear blankets with a DT fusion power of more than 10 MW, are formulated. To conduct the benchmark experiments the technical documentation and calculation models were developed for two blanket micro-models: the molten salt and the heavy water solid-state blankets. The calculations of the neutron spectra, and 37 dosimetric reaction rates that are widely used for the registration of thermal, resonance and threshold (0.25-13.45 MeV) neutrons, were performed for each blanket micro-model. The MCNP code and the neutron data library ENDF/B-VII were used for the calculations. All the calculations were performed for two kinds of neutron source: source I is the fusion source, source II is the source of neutrons generated by the 7Li target irradiated by protons with energy 24.6 MeV. The spectral indexes ratios were calculated to describe the spectrum variations from different neutron sources. The obtained results demonstrate the advantage of using the fusion neutron source in future experiments.

Fluoride salts as phase change materials for thermal energy storage in the temperature range 1000-1400 K

NASA Technical Reports Server (NTRS)

Misra, Ajay K.

1988-01-01

Eutectic compositions and congruently melting intermediate compounds in binary and ternary fluoride salt systems were characterized for potential use as latent heat of fusion phase change materials to store thermal energy in the temperature range 1000-1400 K. The melting points and eutectic compositions for many systems with published phase diagrams were experimentally verified and new eutectic compositions having melting points between 1000 and 1400 K were identified. Heats of fusion of several binary and ternary eutectics and congruently melting compounds were experimentally measured by differential scanning calorimetry. For a few systems in which heats of mixing in the melts have been measured, heats of fusion of the eutectics were calculated from thermodynamic considerations and good agreement was obtained between the measured and calculated values. Several combinations of salts with high heats of fusion per unit mass (greater than 0.7 kJ/g) have been identified for possible use as phase change materials in advanced solar dynamic space power applications.

Development of next generation tempered and ODS reduced activation ferritic/martensitic steels for fusion energy applications

DOE PAGES

Zinkle, S. J.; Boutard, J. L.; Hoelzer, D. T.; ...

2017-06-09

Reduced activation ferritic/martensitic steels are currently the most technologically mature option for the structural material of proposed fusion energy reactors. Advanced next-generation higher performance steels offer the opportunity for improvements in fusion reactor operational lifetime and reliability, superior neutron radiation damage resistance, higher thermodynamic efficiency, and reduced construction costs. The two main strategies for developing improved steels for fusion energy applications are based on (1) an evolutionary pathway using computational thermodynamics modelling and modified thermomechanical treatments (TMT) to produce higher performance reduced activation ferritic/martensitic (RAFM) steels and (2) a higher risk, potentially higher payoff approach based on powder metallurgy techniquesmore » to produce very high strength oxide dispersion strengthened (ODS) steels capable of operation to very high temperatures and with potentially very high resistance to fusion neutron-induced property degradation. The current development status of these next-generation high performance steels is summarized, and research and development challenges for the successful development of these materials are outlined. In conclusion, material properties including temperature-dependent uniaxial yield strengths, tensile elongations, high-temperature thermal creep, Charpy impact ductile to brittle transient temperature (DBTT) and fracture toughness behaviour, and neutron irradiation-induced low-temperature hardening and embrittlement and intermediate-temperature volumetric void swelling (including effects associated with fusion-relevant helium and hydrogen generation) are described for research heats of the new steels.« less

Development of next generation tempered and ODS reduced activation ferritic/martensitic steels for fusion energy applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zinkle, S. J.; Boutard, J. L.; Hoelzer, D. T.

Reduced activation ferritic/martensitic steels are currently the most technologically mature option for the structural material of proposed fusion energy reactors. Advanced next-generation higher performance steels offer the opportunity for improvements in fusion reactor operational lifetime and reliability, superior neutron radiation damage resistance, higher thermodynamic efficiency, and reduced construction costs. The two main strategies for developing improved steels for fusion energy applications are based on (1) an evolutionary pathway using computational thermodynamics modelling and modified thermomechanical treatments (TMT) to produce higher performance reduced activation ferritic/martensitic (RAFM) steels and (2) a higher risk, potentially higher payoff approach based on powder metallurgy techniquesmore » to produce very high strength oxide dispersion strengthened (ODS) steels capable of operation to very high temperatures and with potentially very high resistance to fusion neutron-induced property degradation. The current development status of these next-generation high performance steels is summarized, and research and development challenges for the successful development of these materials are outlined. In conclusion, material properties including temperature-dependent uniaxial yield strengths, tensile elongations, high-temperature thermal creep, Charpy impact ductile to brittle transient temperature (DBTT) and fracture toughness behaviour, and neutron irradiation-induced low-temperature hardening and embrittlement and intermediate-temperature volumetric void swelling (including effects associated with fusion-relevant helium and hydrogen generation) are described for research heats of the new steels.« less

Development of next generation tempered and ODS reduced activation ferritic/martensitic steels for fusion energy applications

NASA Astrophysics Data System (ADS)

Zinkle, S. J.; Boutard, J. L.; Hoelzer, D. T.; Kimura, A.; Lindau, R.; Odette, G. R.; Rieth, M.; Tan, L.; Tanigawa, H.

2017-09-01

Reduced activation ferritic/martensitic steels are currently the most technologically mature option for the structural material of proposed fusion energy reactors. Advanced next-generation higher performance steels offer the opportunity for improvements in fusion reactor operational lifetime and reliability, superior neutron radiation damage resistance, higher thermodynamic efficiency, and reduced construction costs. The two main strategies for developing improved steels for fusion energy applications are based on (1) an evolutionary pathway using computational thermodynamics modelling and modified thermomechanical treatments (TMT) to produce higher performance reduced activation ferritic/martensitic (RAFM) steels and (2) a higher risk, potentially higher payoff approach based on powder metallurgy techniques to produce very high strength oxide dispersion strengthened (ODS) steels capable of operation to very high temperatures and with potentially very high resistance to fusion neutron-induced property degradation. The current development status of these next-generation high performance steels is summarized, and research and development challenges for the successful development of these materials are outlined. Material properties including temperature-dependent uniaxial yield strengths, tensile elongations, high-temperature thermal creep, Charpy impact ductile to brittle transient temperature (DBTT) and fracture toughness behaviour, and neutron irradiation-induced low-temperature hardening and embrittlement and intermediate-temperature volumetric void swelling (including effects associated with fusion-relevant helium and hydrogen generation) are described for research heats of the new steels.

Computation of Electron Impact Ionization Cross sections of Iron Hydrogen Clusters - Relevance in Fusion Plasmas

NASA Astrophysics Data System (ADS)

Patel, Umang; Joshipura, K. N.

2017-04-01

Plasma-wall interaction (PWI) is one of the key issues in nuclear fusion research. In nuclear fusion devices, such as the JET tokamak or the ITER, first-wall materials will be directly exposed to plasma components. Erosion of first-wall materials is a consequence of the impact of hydrogen and its isotopes as main constituents of the hot plasma. Besides the formation of gas-phase atomic species in various charge states, di- and polyatomic molecular species are expected to be formed via PWI processes. These compounds may profoundly disturb the fusion plasma, may lead to unfavorable re-deposition of materials and composites in other areas of the vessel. Interaction between atoms, molecules as well transport of impurities are of interest for modelling of fusion plasma. Qion by electron impact are such process also important in low temperature plasma processing, astrophysics etc. We reported electron impact Qionfor iron hydrogen clusters, FeHn (n = 1 to 10) from ionization threshold to 2000 eV. A semi empirical approach called Complex Scattering Potential - Ionization Contribution (CSP-ic) has been employed for the reported calculation. In context of fusion relevant species Qion were reported for beryllium and its hydrides, tungsten and its oxides and cluster of beryllium-tungsten by Huber et al.. Iron hydrogen clusters are another such species whose Qion were calculated through DM and BEB formalisms, same has been compared with present calculations.

Materials Studies for Magnetic Fusion Energy Applications at Low Temperatures - 6.

DTIC Science & Technology

1983-05-01

structures for the superconducting magnets of magnetic fusion energy power plants and prototypes. The program was conceived and developed jointly by the...staffs of the National Bureau of Standards and the Office of Fusion Energy of the Department of Energy; it is managed by NBS and sponsored by DoE

Rheological behavior and cryogenic properties of cyanate ester/epoxy insulation material for fusion superconducting magnet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Z. X.; Huang, C. J.; Li, L. F.

2014-01-27

In a Tokamak fusion reactor device like ITER, insulation materials for superconducting magnets are usually fabricated by a vacuum pressure impregnation (VPI) process. Thus these insulation materials must exhibit low viscosity, long working life as well as good radiation resistance. Previous studies have indicated that cyanate ester (CE) blended with epoxy has an excellent resistance against neutron irradiation which is expected to be a candidate insulation material for a fusion magnet. In this work, the rheological behavior of a CE/epoxy (CE/EP) blend containing 40% CE was investigated with non-isothermal and isothermal viscosity experiments. Furthermore, the cryogenic mechanical and electrical propertiesmore » of the composite were evaluated in terms of interlaminar shear strength and electrical breakdown strength. The results showed that CE/epoxy blend had a very low viscosity and an exceptionally long processing life of about 4 days at 60 °C.« less

Laser erosion diagnostics of plasma facing materials with displacement sensors and their application to safeguard monitors to protect nuclear fusion chambers

NASA Astrophysics Data System (ADS)

Kasuya, Koichi; Motokoshi, Shinji; Taniguchi, Seiji; Nakai, Mitsuo; Tokunaga, Kazutoshi; Mroz, Waldemar; Budner, Boguslaw; Korczyc, Barbara

2015-02-01

Tungsten and SiC are candidates for the structural materials of the nuclear fusion reactor walls, while CVD poly-crystal diamond is candidate for the window material under the hazardous fusion stresses. We measured the surface endurance strength of such materials with commercial displacement sensors and our recent evaluation method. The pulsed high thermal input was put into the material surfaces by UV lasers, and the surface erosions were diagnosed. With the increase of the total number of the laser shots per position, the crater depth increased gradually. The 3D and 2D pictures of the craters were gathered and compared under various experimental conditions. For example, the maximum crater depths were plotted as a function of shot accumulated numbers, from which we evaluated the threshold thermal input for the surface erosions to be induced. The simple comparison-result showed that tungsten was stronger roughly two times than SiC. Then we proposed how to monitor the surface conditions of combined samples with such diamonds coated with thin tungsten layers, when we use such samples as parts of divertor inner walls, fusion chamber first walls, and various diagnostic windows. We investigated how we might be able to measure the inner surface erosions with the same kinds of displacement sensors. We found out the measurable maximum thickness of such diamond which is useful to monitor the erosion. Additionally we showed a new scheme of fusion reactor systems with injectors for anisotropic pellets and heating lasers under the probable use of W and/or SiC.

Radioactivity measurements of ITER materials using the TFTR D-T neutron field

NASA Astrophysics Data System (ADS)

Kumar, A.; Abdou, M. A.; Barnes, C. W.; Kugel, H. W.

1994-06-01

The availability of high D-T fusion neutron yields at TFTR has provided a useful opportunity to directly measure D-T neutron-induced radioactivity in a realistic tokamak fusion reactor environment for materials of vital interest to ITER. These measurements are valuable for characterizing radioactivity in various ITER candidate materials, for validating complex neutron transport calculations, and for meeting fusion reactor licensing requirements. The radioactivity measurements at TFTR involve potential ITER materials including stainless steel 316, vanadium, titanium, chromium, silicon, iron, cobalt, nickel, molybdenum, aluminum, copper, zinc, zirconium, niobium, and tungsten. Small samples of these materials were irradiated close to the plasma and just outside the vacuum vessel wall of TFTR, locations of different neutron energy spectra. Saturation activities for both threshold and capture reactions were measured. Data from dosimetric reactions have been used to obtain preliminary neutron energy spectra. Spectra from the first wall were compared to calculations from ITER and to measurements from accelerator-based tests.

Neutron-Irradiated Samples as Test Materials for MPEX

DOE PAGES

Ellis, Ronald James; Rapp, Juergen

2015-10-09

Plasma Material Interaction (PMI) is a major concern in fusion reactor design and analysis. The Material-Plasma Exposure eXperiment (MPEX) will explore PMI under fusion reactor plasma conditions. Samples with accumulated displacements per atom (DPA) damage produced by fast neutron irradiations in the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) will be studied in the MPEX facility. This paper presents assessments of the calculated induced radioactivity and resulting radiation dose rates of a variety of potential fusion reactor plasma-facing materials (such as tungsten). The scientific code packages MCNP and SCALE were used to simulate irradiation of themore » samples in HFIR including the generation and depletion of nuclides in the material and the subsequent composition, activity levels, gamma radiation fields, and resultant dose rates as a function of cooling time. A challenge of the MPEX project is to minimize the radioactive inventory in the preparation of the samples and the sample dose rates for inclusion in the MPEX facility.« less

Application of Recommended Design Practices for Conceptual Nuclear Fusion Space Propulsion Systems

NASA Technical Reports Server (NTRS)

Williams, Craig H.

2004-01-01

An AIAA Special Project Report was recently produced by AIAA's Nuclear and Future Flight Propulsion Technical Committee and is currently in peer review. The Report provides recommended design practices for conceptual engineering studies of nuclear fusion space propulsion systems. Discussion and recommendations are made on key topics including design reference missions, degree of technological extrapolation and concomitant risk, thoroughness in calculating mass properties (nominal mass properties, weight-growth contingency and propellant margins, and specific impulse), and thoroughness in calculating power generation and usage (power-flow, power contingencies, specific power). The report represents a general consensus of the nuclear fusion space propulsion system conceptual design community and proposes 15 recommendations. This paper expands on the Report by providing specific examples illustrating how to apply each of the recommendations.

A Fusion Nuclear Science Facility for a fast-track path to DEMO

DOE PAGES

Garofalo, Andrea M.; Abdou, M.; Canik, John M.; ...

2014-10-01

An accelerated fusion energy development program, a “fast-track” approach, requires developing an understanding of fusion nuclear science (FNS) in parallel with research on ITER to study burning plasmas. A Fusion Nuclear Science Facility (FNSF) in parallel with ITER provides the capability to resolve FNS feasibility issues related to power extraction, tritium fuel sustainability, and reliability, and to begin construction of DEMO upon the achievement of Q~10 in ITER. Fusion nuclear components, including the first wall (FW)/blanket, divertor, heating/fueling systems, etc. are complex systems with many inter-related functions and different materials, fluids, and physical interfaces. These in-vessel nuclear components must operatemore » continuously and reliably with: (a) Plasma exposure, surface particle & radiation loads, (b) High energy 2 neutron fluxes and their interactions in materials (e.g. peaked volumetric heating with steep gradients, tritium production, activation, atomic displacements, gas production, etc.), (c) Strong magnetic fields with temporal and spatial variations (electromagnetic coupling to the plasma including off-normal events like disruptions), and (d) a High temperature, high vacuum, chemically active environment. While many of these conditions and effects are being studied with separate and multiple effect experimental test stands and modeling, fusion nuclear conditions cannot be completely simulated outside the fusion environment. This means there are many new multi-physics, multi-scale phenomena and synergistic effects yet to be discovered and accounted for in the understanding, design and operation of fusion as a self-sustaining, energy producing system, and significant experimentation and operational experience in a true fusion environment is an essential requirement. In the following sections we discuss the FNSF objectives, describe the facility requirements and a facility concept and operation approach that can accomplish those objectives, and assess the readiness to construct with respect to several key FNSF issues: materials, steady-state operation, disruptions, power exhaust, and breeding blanket. Finally we present our conclusions.« less

Manufacturing Systems Demonstration: Bimetallic Friction STIR Joining of AA6061 and High Hardness Steel

DTIC Science & Technology

2013-05-31

fusion welding and virtually eliminates the material porosity inherent with liquid alloy processes. Also because less heat is input to the material...Fe intermetallic present. Mechanical load testing determined that the bimetallic FSP joint was stronger than similar AA6061-to-AA6061 fusion- welded and...5 b) Weld Coupon Fixture ........................................................................................ 5 2. Friction Stir Tools

Concept for Classifying Facade Elements Based on Material, Geometry and Thermal Radiation Using Multimodal Uav Remote Sensing

NASA Astrophysics Data System (ADS)

Ilehag, R.; Schenk, A.; Hinz, S.

2017-08-01

This paper presents a concept for classification of facade elements, based on the material and the geometry of the elements in addition to the thermal radiation of the facade with the usage of a multimodal Unmanned Aerial Vehicle (UAV) system. Once the concept is finalized and functional, the workflow can be used for energy demand estimations for buildings by exploiting existing methods for estimation of heat transfer coefficient and the transmitted heat loss. The multimodal system consists of a thermal, a hyperspectral and an optical sensor, which can be operational with a UAV. While dealing with sensors that operate in different spectra and have different technical specifications, such as the radiometric and the geometric resolution, the challenges that are faced are presented. Addressed are the different approaches of data fusion, such as image registration, generation of 3D models by performing image matching and the means for classification based on either the geometry of the object or the pixel values. As a first step towards realizing the concept, the result from a geometric calibration with a designed multimodal calibration pattern is presented.

SEAL Studies of Variant Blanket Concepts and Materials

NASA Astrophysics Data System (ADS)

Cook, I.; Taylor, N. P.; Forty, C. B. A.; Han, W. E.

1997-09-01

Within the European SEAL ( Safety and Environmental Assessment of fusion power, Long-term) program, safety and environmental assessments have been performed which extend the results of the earlier SEAFP (Safety and Environmental Assessment of Fusion Power) program to a wider range of blanket designs and material choices. The four blanket designs analysed were those which had been developed within the Blanket program of the European Fusion Programme. All four are based on martensitic steel as structural material, and otherwise may be summarized as: water-cooled lithium-lead; dual-cooled lithium-lead; helium-cooled lithium silicate (BOT geometry); helium-cooled lithium aluminate (or zirconate) (BIT geometry). The results reveal that all the blankets show the favorable S&E characteristics of fusion, though there are interesting and significant differences between them. The key results are described. Assessments have also been performed of a wider range of materials than was considered in SEAFP. These were: an alternative vanadium alloy, an alternative low-activation martensitic steel, titanium-aluminum intermetallic, and SiC composite. Assessed impurities were included in the compositions, and these had very important effects upon some of the results. Key results impacting upon accident characteristics, recycling, and waste management are described.

21 CFR 888.3080 - Intervertebral body fusion device.

Code of Federal Regulations, 2012 CFR

2012-04-01

... devices that contain bone grafting material. The special control is the FDA guidance document entitled... devices that include any therapeutic biologic (e.g., bone morphogenic protein). Intervertebral body fusion...

21 CFR 888.3080 - Intervertebral body fusion device.

Code of Federal Regulations, 2010 CFR

2010-04-01

... devices that contain bone grafting material. The special control is the FDA guidance document entitled... devices that include any therapeutic biologic (e.g., bone morphogenic protein). Intervertebral body fusion...

21 CFR 888.3080 - Intervertebral body fusion device.

Code of Federal Regulations, 2013 CFR

2013-04-01

... devices that contain bone grafting material. The special control is the FDA guidance document entitled... devices that include any therapeutic biologic (e.g., bone morphogenic protein). Intervertebral body fusion...

21 CFR 888.3080 - Intervertebral body fusion device.

Code of Federal Regulations, 2014 CFR

2014-04-01

... devices that contain bone grafting material. The special control is the FDA guidance document entitled... devices that include any therapeutic biologic (e.g., bone morphogenic protein). Intervertebral body fusion...

Five major controversial issues about fusion level selection in corrective surgery for adolescent idiopathic scoliosis: a narrative review.

PubMed

Lee, Choon Sung; Hwang, Chang Ju; Lee, Dong-Ho; Cho, Jae Hwan

2017-07-01

Shoulder imbalance, coronal decompensation, and adding-on phenomenon following corrective surgery in patients with adolescent idiopathic scoliosis are known to be related to the fusion level selected. Although many studies have assessed the appropriate selection of the proximal and distal fusion level, no definite conclusions have been drawn thus far. We aimed to assess the problems with fusion level selection for corrective surgery in patients with adolescent idiopathic scoliosis, and to enhance understanding about these problems. This study is a narrative review. We conducted a literature search of fusion level selection in corrective surgery for adolescent idiopathic scoliosis. Accordingly, we selected and reviewed five debatable topics related to fusion level selection: (1) selective thoracic fusion; (2) selective thoracolumbar-lumbar (TL-L) fusion; (3) adding-on phenomenon; (4) distal fusion level selection for major TL-L curves; and (5) proximal fusion level selection and shoulder imbalance. Selective fusion can be chosen in specific curve types, although there is a risk of coronal decompensation or adding-on phenomenon. Generally, wider indications for selective fusions are usually associated with more frequent complications. Despite the determination of several indications for selective fusion to avoid such complications, no clear guidelines have been established. Although authors have suggested various criteria to prevent the adding-on phenomenon, no consensus has been reached on the appropriate selection of lower instrumented vertebra. The fusion level selection for major TL-L curves primarily focuses on whether distal fusion can terminate at L3, a topic that remains unclear. Furthermore, because of the presence of several related factors and complications, proximal level selection and shoulder imbalance has been constantly debated and remains controversial from its etiology to its prevention. Although several difficult problems in the diagnosis and treatment of adolescent idiopathic scoliosis have been resolved by understanding its mechanism and via technical advancement, no definite guideline for fusion level selection has been established. A review of five major controversial issues about fusion level selection could provide better understanding of adolescent idiopathic scoliosis. We believe that a thorough validation study of the abovementioned controversial issues can help address them. Copyright © 2017 Elsevier Inc. All rights reserved.

Numerical and Experimental Study of Ti6Al4V Components Manufactured Using Powder Bed Fusion Additive Manufacturing

NASA Astrophysics Data System (ADS)

Zielinski, Jonas; Mindt, Hans-Wilfried; Düchting, Jan; Schleifenbaum, Johannes Henrich; Megahed, Mustafa

2017-12-01

Powder bed fusion additive manufacturing of titanium alloys is an interesting manufacturing route for many applications requiring high material strength combined with geometric complexity. Managing powder bed fusion challenges, including porosity, surface finish, distortions and residual stresses of as-built material, is the key to bringing the advantages of this process to production main stream. This paper discusses the application of experimental and numerical analysis towards optimizing the manufacturing process of a demonstration component. Powder characterization including assessment of the reusability, assessment of material consolidation and process window optimization is pursued prior to applying the identified optima to study the distortion and residual stresses of the demonstrator. Comparisons of numerical predictions with measurements show good correlations along the complete numerical chain.

Final Technical Report -- Bridging the PSI Knowledge Gap: A Multiscale Approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whyte, Dennis

2014-12-12

The Plasma Surface Interactions (PSI) Science Center formed by the grant undertook a multidisciplinary set of studies on the complex interface between the plasma and solid states of matter. The strategy of the center was to combine and integrate the experimental, diagnostic and modeling toolkits from multiple institutions towards specific PSI problems. In this way the Center could tackle integrated science issues which were not addressable by single institutions, as well as evolve the underlying science of the PSI in a more general way than just for fusion applications. The overall strategy proved very successful. The research result and highlightsmore » of the MIT portion of the Center are primarily described. A particular highlight is the study of tungsten nano-tendril growth in the presence of helium plasmas. The Center research provided valuable new insights to the mechanisms controlling the nano-tendrils by developing coupled modeling and in situ diagnostic methods which could be directly compared. For example, the role of helium accumulation in tungsten distortion in the surface was followed with unique in situ helium concentration diagnostics developed. These depth-profiled, time-resolved helium concentration measurements continue to challenge the numerical models of nano-tendrils. The Center team also combined its expertise on tungsten nano-tendrils to demonstrate for the first time the growth of the tendrils in a fusion environment on the Alcator C-Mod fusion experiment, thus having significant impact on the broader fusion research effort. A new form of isolated nano-tendril “columns” were identified which are now being used to understand the underlying mechanisms controlling the tendril growth. The Center also advanced PSI science on a broader front with a particular emphasis on developing a wide range of in situ PSI diagnostic tools at the DIONISOS facility at MIT. For example the strong suppression of sputtering by the certain combination of light-species plasmas and metals was experimentally studied with independent measurement methods across the Center. This surprising result challenges the universal use of the binary-collision approximation in sputtering predictions and continues to be the subject of study. In order to address this issue MIT developed a new in situ erosion measurement technique based on ion beam analysis which can be used at elevated material temperatures. This exciting new technique is now being used to study material erosion in high performance plasma thrusters for space exploration and is being adopted to fusion experimental devices. This is an indicator of the positive synergies that arise from such a Center, with the research having impact beyond the initial area of study. The Center also served successfully as an organizing force for communication to the science community. The MIT members of the Center provided many high-profile overview presentations at prestigious international conferences and national workshops. The research resulted in three student theses and 24 peer-reviewed publications. PSI research continues to be identified as a critical area for fusion energy.« less

Plasma wall interaction, a key issue on the way to a steady state burning fusion device

NASA Astrophysics Data System (ADS)

Philipps, V.

2006-04-01

The International Tokamak Experimental Reactor (ITER), the first burning fusion plasma experiment based on the tokamak principle, is ready for construction. It is based on many years of fusion research resulting in a robust design in most of the areas. Present day fusion research concentrates on the remaining critical issues which are, to a large extent, connected with processes of plasma wall interaction. This is mainly due to extended duty cycle and the increase of the plasma stored energy in comparison with present-day machines. Critical topics are the lifetime of the plasma facing components (PFC) and the long-term tritium retention. These processes are controlled mainly by material erosion, both during steady state operation and transient power losses (disruptions and edge localized modes (ELMs)) and short- and long-range material migration and re-deposition. The extrapolation from present-day 'full carbon wall' devices suggests that the long-term tritium retention in a burning fusion device would be unacceptably high under these conditions allowing for only an unacceptable limited number of pulses in a D T mixture. As a consequence of this, research activities have been strengthened to understand in more detail the underlying processes of material erosion and re-deposition, to develop methods to remove retained tritium from the PFCs and remote areas of a fusion device and to explore these processes and the plasma performance in more detail with metallic PFC, such as beryllium (Be) and tungsten (W), which are foreseen for the ITER experiment. This paper outlines the main physical mechanisms leading to material erosion, migration and re-deposition and the associated fuel retention. It addresses the experimental database in these areas and describes the further research strategies that will be needed to tackle critical issues.

Optimization of tritium breeding and shielding analysis to plasma in ITER fusion reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Indah Rosidah, M., E-mail: indah.maymunah@gmail.com; Suud, Zaki, E-mail: szaki@fi.itb.ac.id; Yazid, Putranto Ilham

The development of fusion energy is one of the important International energy strategies with the important milestone is ITER (International Thermonuclear Experimental Reactor) project, initiated by many countries, such as: America, Europe, and Japan who agreed to set up TOKAMAK type fusion reactor in France. In ideal fusion reactor the fuel is purely deuterium, but it need higher temperature of reactor. In ITER project the fuels are deuterium and tritium which need lower temperature of the reactor. In this study tritium for fusion reactor can be produced by using reaction of lithium with neutron in the blanket region. With themore » tritium breeding blanket which react between Li-6 in the blanket with neutron resulted from the plasma region. In this research the material used in each layer surrounding the plasma in the reactor is optimized. Moreover, achieving self-sufficiency condition in the reactor in order tritium has enough availability to be consumed for a long time. In order to optimize Tritium Breeding Ratio (TBR) value in the fusion reactor, there are several strategies considered here. The first requirement is making variation in Li-6 enrichment to be 60%, 70%, and 90%. But, the result of that condition can not reach TBR value better than with no enrichment. Because there is reduction of Li-7 percent when increasing Li-6 percent. The other way is converting neutron multiplier material with Pb. From this, we get TBR value better with the Be as neutron multiplier. Beside of TBR value, fusion reactor can analyze the distribution of neutron flux and dose rate of neutron to know the change of neutron concentration for each layer in reactor. From the simulation in this study, 97% neutron concentration can be absorbed by material in reactor, so it is good enough. In addition, it is required to analyze spectrum neutron energy in many layers in the fusion reactor such as in blanket, coolant, and divertor. Actually material in that layer can resist in high temperature and high pressure condition for more than ten years.« less

Inertial Fusion Power Plant Concept of Operations and Maintenance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anklam, T.; Knutson, B.; Dunne, A. M.

2015-01-15

Parsons and LLNL scientists and engineers performed design and engineering work for power plant pre-conceptual designs based on the anticipated laser fusion demonstrations at the National Ignition Facility (NIF). Work included identifying concepts of operations and maintenance (O&M) and associated requirements relevant to fusion power plant systems analysis. A laser fusion power plant would incorporate a large process and power conversion facility with a laser system and fusion engine serving as the heat source, based in part on some of the systems and technologies advanced at NIF. Process operations would be similar in scope to those used in chemical, oilmore » refinery, and nuclear waste processing facilities, while power conversion operations would be similar to those used in commercial thermal power plants. While some aspects of the tritium fuel cycle can be based on existing technologies, many aspects of a laser fusion power plant presents several important and unique O&M requirements that demand new solutions. For example, onsite recovery of tritium; unique remote material handling systems for use in areas with high radiation, radioactive materials, or high temperatures; a five-year fusion engine target chamber replacement cycle with other annual and multi-year cycles anticipated for major maintenance of other systems, structures, and components (SSC); and unique SSC for fusion target waste recycling streams. This paper describes fusion power plant O&M concepts and requirements, how O&M requirements could be met in design, and how basic organizational and planning issues can be addressed for a safe, reliable, economic, and feasible fusion power plant.« less

Inertial fusion power plant concept of operations and maintenance

NASA Astrophysics Data System (ADS)

Knutson, Brad; Dunne, Mike; Kasper, Jack; Sheehan, Timothy; Lang, Dwight; Anklam, Tom; Roberts, Valerie; Mau, Derek

2015-02-01

Parsons and LLNL scientists and engineers performed design and engineering work for power plant pre-conceptual designs based on the anticipated laser fusion demonstrations at the National Ignition Facility (NIF). Work included identifying concepts of operations and maintenance (O&M) and associated requirements relevant to fusion power plant systems analysis. A laser fusion power plant would incorporate a large process and power conversion facility with a laser system and fusion engine serving as the heat source, based in part on some of the systems and technologies advanced at NIF. Process operations would be similar in scope to those used in chemical, oil refinery, and nuclear waste processing facilities, while power conversion operations would be similar to those used in commercial thermal power plants. While some aspects of the tritium fuel cycle can be based on existing technologies, many aspects of a laser fusion power plant presents several important and unique O&M requirements that demand new solutions. For example, onsite recovery of tritium; unique remote material handling systems for use in areas with high radiation, radioactive materials, or high temperatures; a five-year fusion engine target chamber replacement cycle with other annual and multi-year cycles anticipated for major maintenance of other systems, structures, and components (SSC); and unique SSC for fusion target waste recycling streams. This paper describes fusion power plant O&M concepts and requirements, how O&M requirements could be met in design, and how basic organizational and planning issues can be addressed for a safe, reliable, economic, and feasible fusion power plant.

Fusion of magnetic resonance angiography and magnetic resonance imaging for surgical planning for meningioma--technical note.

PubMed

Kashimura, Hiroshi; Ogasawara, Kuniaki; Arai, Hiroshi; Beppu, Takaaki; Inoue, Takashi; Takahashi, Tsutomu; Matsuda, Koichi; Takahashi, Yujiro; Fujiwara, Shunrou; Ogawa, Akira

2008-09-01

A fusion technique for magnetic resonance (MR) angiography and MR imaging was developed to help assess the peritumoral angioarchitecture during surgical planning for meningioma. Three-dimensional time-of-flight (3D-TOF) and 3D-spoiled gradient recalled (SPGR) datasets were obtained from 10 patients with intracranial meningioma, and fused using newly developed volume registration and visualization software. Maximum intensity projection (MIP) images from 3D-TOF MR angiography and axial SPGR MR imaging were displayed at the same time on the monitor. Selecting a vessel on the real-time MIP image indicated the corresponding points on the axial image automatically. Fusion images showed displacement of the anterior cerebral or middle cerebral artery in 7 patients and encasement of the anterior cerebral arteries in 1 patient, with no relationship between the main arterial trunk and tumor in 2 patients. Fusion of MR angiography and MR imaging can clarify relationships between the intracranial vasculature and meningioma, and may be helpful for surgical planning for meningioma.

Current strategies for the restoration of adequate lordosis during lumbar fusion

PubMed Central

Barrey, Cédric; Darnis, Alice

2015-01-01

Not restoring the adequate lumbar lordosis during lumbar fusion surgery may result in mechanical low back pain, sagittal unbalance and adjacent segment degeneration. The objective of this work is to describe the current strategies and concepts for restoration of adequate lordosis during fusion surgery. Theoretical lordosis can be evaluated from the measurement of the pelvic incidence and from the analysis of spatial organization of the lumbar spine with 2/3 of the lordosis given by the L4-S1 segment and 85% by the L3-S1 segment. Technical aspects involve patient positioning on the operating table, release maneuvers, type of instrumentation used (rod, screw-rod connection, interbody cages), surgical sequence and the overall surgical strategy. Spinal osteotomies may be required in case of fixed kyphotic spine. AP combined surgery is particularly efficient in restoring lordosis at L5-S1 level and should be recommended. Finally, not one but several strategies may be used to achieve the need for restoration of adequate lordosis during fusion surgery. PMID:25621216

The da Vinci robotic surgical assisted anterior lumbar interbody fusion: technical development and case report.

PubMed

Beutler, William J; Peppelman, Walter C; DiMarco, Luciano A

2013-02-15

Technique development to use the da Vince Robotic Surgical System for anterior lumbar interbody fusion at L5-S1 is detailed. A case report is also presented. To evaluate and develop the da Vinci robotic assisted laparoscopic anterior lumbar stand-alone interbody fusion procedure. Anterior lumbar interbody fusion is a common procedure associated with potential morbidity related to the surgical approach. The da Vinci robot provides intra-abdominal dissection and visualization advantages compared with the traditional open and laparoscopic approach. The surgical techniques for approach to the anterior lumbar spine using the da Vinci robot were developed and modified progressively beginning with operative models followed by placement of an interbody fusion cage in the living porcine model. Development continued to progress with placement of fusion cage in a human cadaver, completed first in the laboratory setting and then in the operating room. Finally, the first patient with fusion completed using the da Vinci robot-assisted approach is presented. The anterior transperitoneal approach to the lumbar spine is accomplished with enhanced visualization and dissection capability, with maintenance of pneumoperitoneum using the da Vinci robot. Blood loss is minimal. The visualization inside the disc space and surrounding structures was considered better than current open and laparoscopic techniques. The da Vinci robot Surgical System technique continues to develop and is now described for the transperitoneal approach to the anterior lumbar spine. 4.

An in situ accelerator-based diagnostic for plasma-material interactions science on magnetic fusion devices.

PubMed

Hartwig, Zachary S; Barnard, Harold S; Lanza, Richard C; Sorbom, Brandon N; Stahle, Peter W; Whyte, Dennis G

2013-12-01

This paper presents a novel particle accelerator-based diagnostic that nondestructively measures the evolution of material surface compositions inside magnetic fusion devices. The diagnostic's purpose is to contribute to an integrated understanding of plasma-material interactions in magnetic fusion, which is severely hindered by a dearth of in situ material surface diagnosis. The diagnostic aims to remotely generate isotopic concentration maps on a plasma shot-to-shot timescale that cover a large fraction of the plasma-facing surface inside of a magnetic fusion device without the need for vacuum breaks or physical access to the material surfaces. Our instrument uses a compact (~1 m), high-current (~1 milliamp) radio-frequency quadrupole accelerator to inject 0.9 MeV deuterons into the Alcator C-Mod tokamak at MIT. We control the tokamak magnetic fields--in between plasma shots--to steer the deuterons to material surfaces where the deuterons cause high-Q nuclear reactions with low-Z isotopes ~5 μm into the material. The induced neutrons and gamma rays are measured with scintillation detectors; energy spectra analysis provides quantitative reconstruction of surface compositions. An overview of the diagnostic technique, known as accelerator-based in situ materials surveillance (AIMS), and the first AIMS diagnostic on the Alcator C-Mod tokamak is given. Experimental validation is shown to demonstrate that an optimized deuteron beam is injected into the tokamak, that low-Z isotopes such as deuterium and boron can be quantified on the material surfaces, and that magnetic steering provides access to different measurement locations. The first AIMS analysis, which measures the relative change in deuterium at a single surface location at the end of the Alcator C-Mod FY2012 plasma campaign, is also presented.

Fission-suppressed fusion breeder on the thorium cycle and nonproliferation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moir, R. W.

2012-06-19

Fusion reactors could be designed to breed fissile material while suppressing fissioning thereby enhancing safety. The produced fuel could be used to startup and makeup fuel for fission reactors. Each fusion reaction can produce typically 0.6 fissile atoms and release about 1.6 times the 14 MeV neutron's energy in the blanket in the fission-suppressed design. This production rate is 2660 kg/1000 MW of fusion power for a year. The revenues would be doubled from such a plant by selling fuel at a price of 60/g and electricity at $0.05/kWh for Q=P{sub fusion}/P{sub input}=4. Fusion reactors could be designed to destroymore » fission wastes by transmutation and fissioning but this is not a natural use of fusion whereas it is a designed use of fission reactors. Fusion could supply makeup fuel to fission reactors that were dedicated to fissioning wastes with some of their neutrons. The design for safety and heat removal and other items is already accomplished with fission reactors. Whereas fusion reactors have geometry that compromises safety with a complex and thin wall separating the fusion zone from the blanket zone where wastes could be destroyed. Nonproliferation can be enhanced by mixing {sup 233}U with {sup 238}U. Also nonproliferation is enhanced in typical fission-suppressed designs by generating up to 0.05 {sup 232}U atoms for each {sup 233}U atom produced from thorium, about twice the IAEA standards of 'reduced protection' or 'self protection.' With 2.4%{sup 232}U, high explosive material is predicted to degrade owing to ionizing radiation after a little over 1/2 year and the heat rate is 77 W just after separation and climbs to over 600 W ten years later. The fissile material can be used to fuel most any fission reactor but is especially appropriate for molten salt reactors (MSR) also called liquid fluoride thorium reactors (LFTR) because of the molten fuel does not need hands on fabrication and handling.« less

Different source image fusion based on FPGA

NASA Astrophysics Data System (ADS)

Luo, Xiao; Piao, Yan

2016-03-01

The fusion technology of video image is to make the video obtained by different image sensors complementary to each other by some technical means, so as to obtain the video information which is rich in information and suitable for the human eye system. Infrared cameras in harsh environments such as when smoke, fog and low light situations penetrating power, but the ability to obtain the details of the image is poor, does not meet the human visual system. Single visible light imaging can be rich in detail, high resolution images and for the visual system, but the visible image easily affected by the external environment. Infrared image and visible image fusion process involved in the video image fusion algorithm complexity and high calculation capacity, have occupied more memory resources, high clock rate requirements, such as software, c ++, c, etc. to achieve more, but based on Hardware platform less. In this paper, based on the imaging characteristics of infrared images and visible light images, the software and hardware are combined to obtain the registration parameters through software matlab, and the gray level weighted average method is used to implement the hardware platform. Information fusion, and finally the fusion image can achieve the goal of effectively improving the acquisition of information to increase the amount of information in the image.

System and method for producing metallic iron

DOEpatents

Englund, David J.; Schlichting, Mark; Meehan, John; Crouch, Jeremiah; Wilson, Logan

2014-07-29

A method of production of metallic iron nodules comprises assembling a hearth furnace having a moveable hearth comprising refractory material and having a conversion zone and a fusion zone, providing a hearth material layer comprising carbonaceous material on the refractory material, providing a layer of reducible material comprising and iron bearing material arranged in discrete portions over at least a portion of the hearth material layer, delivering oxygen gas into the hearth furnace to a ratio of at least 0.8:1 ponds of oxygen to pounds of iron in the reducible material to heat the conversion zone to a temperature sufficient to at least partially reduce the reducible material and to heat the fusion zone to a temperature sufficient to at least partially reduce the reducible material, and heating the reducible material to form one or more metallic iron nodules and slag.

49 CFR 192.283 - Plastic pipe: Qualifying joining procedures.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Materials Other Than by Welding § 192.283 Plastic pipe: Qualifying joining procedures. (a) Heat fusion... for making plastic pipe joints by a heat fusion, solvent cement, or adhesive method, the procedure...

49 CFR 192.283 - Plastic pipe: Qualifying joining procedures.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Materials Other Than by Welding § 192.283 Plastic pipe: Qualifying joining procedures. (a) Heat fusion... for making plastic pipe joints by a heat fusion, solvent cement, or adhesive method, the procedure...

49 CFR 192.283 - Plastic pipe: Qualifying joining procedures.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Materials Other Than by Welding § 192.283 Plastic pipe: Qualifying joining procedures. (a) Heat fusion... for making plastic pipe joints by a heat fusion, solvent cement, or adhesive method, the procedure...

49 CFR 192.283 - Plastic pipe: Qualifying joining procedures.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Materials Other Than by Welding § 192.283 Plastic pipe: Qualifying joining procedures. (a) Heat fusion... for making plastic pipe joints by a heat fusion, solvent cement, or adhesive method, the procedure...

Control of a laser inertial confinement fusion-fission power plant

DOEpatents

Moses, Edward I.; Latkowski, Jeffery F.; Kramer, Kevin J.

2015-10-27

A laser inertial-confinement fusion-fission energy power plant is described. The fusion-fission hybrid system uses inertial confinement fusion to produce neutrons from a fusion reaction of deuterium and tritium. The fusion neutrons drive a sub-critical blanket of fissile or fertile fuel. A coolant circulated through the fuel extracts heat from the fuel that is used to generate electricity. The inertial confinement fusion reaction can be implemented using central hot spot or fast ignition fusion, and direct or indirect drive. The fusion neutrons result in ultra-deep burn-up of the fuel in the fission blanket, thus enabling the burning of nuclear waste. Fuels include depleted uranium, natural uranium, enriched uranium, spent nuclear fuel, thorium, and weapons grade plutonium. LIFE engines can meet worldwide electricity needs in a safe and sustainable manner, while drastically shrinking the highly undesirable stockpiles of depleted uranium, spent nuclear fuel and excess weapons materials.

Nuclear design of a very-low-activation fusion reactor

NASA Astrophysics Data System (ADS)

Cheng, E. T.; Hopkins, G. R.

1983-06-01

The nuclear design aspects of using very-low-activation materials, such as SiC, MgO, and aluminum for fusion-reactor first wall, blanket, and shield applications were investigated. In addition to the advantage of very-low radioactive inventory, it was found that the very-low-activation fusion reactor can also offer an adequate tritium-breeding ratio and substantial amount of blanket nuclear heating as a conventional-material-structured reactor does. The most-stringent design constraint found in a very-low-activation fusion reactor is the limited space available in the inboard region of a Tokamak concept for shielding to protect the superconducting toroidal field coil. A reference design was developed which mitigates the constraint by adopting a removable tungsten shield design that retains the inboard dimensions and gives the same shield performance as the reference STARFIRE Tokamak reactor design.

Current Trends of Blanket Research and Deveopment in Japan 4.Blanket Technology Development Using ITER for Demonstration and Commercial Fusion Power Plant

NASA Astrophysics Data System (ADS)

Akiba, Masato; Jitsukawa, Shiroh; Muroga, Takeo

This paper describes the status of blanket technology and material development for fusion power demonstration plants and commercial fusion plants. In particular, the ITER Test Blanket Module, IFMIF, JAERI/DOE HFIR and JUPITER-II projects are highlighted, which have the important role to develop these technology. The ITER Test Blanket Module project has been conducted to demonstrate tritium breeding and power generation using test blanket modules, which will be installed into the ITER facility. For structural material development, the present research status is overviewed on reduced activation ferritic steel, vanadium alloys, and SiC/SiC composites.

SNARE-mediated membrane fusion in autophagy

PubMed Central

Wang, Yongyao; Li, Linsen; Hou, Chen; Lai, Ying; Long, Jiangang; Liu, Jiankang; Zhong, Qing; Diao, Jiajie

2016-01-01

Autophagy, a conserved self-eating process for the bulk degradation of cytoplasmic materials, involves double-membrane autophagosomes formed when an isolation membrane emerges and their direct fusion with lysosomes for degradation. For the early biogenesis of autophagosomes and their later degradation in lysosomes, membrane fusion is necessary, although different sets of genes and autophagy-related proteins involved in distinct fusion steps have been reported. To clarify the molecular mechanism of membrane fusion in autophagy, to not only expand current knowledge of autophagy, but also benefit human health, this review discusses key findings that elucidate the unique membrane dynamics of autophagy. PMID:27422330

Interactive Plasma Physics Education Using Data from Fusion Experiments

NASA Astrophysics Data System (ADS)

Calderon, Brisa; Davis, Bill; Zwicker, Andrew

2010-11-01

The Internet Plasma Physics Education Experience (IPPEX) website was created in 1996 to give users access to data from plasma and fusion experiments. Interactive material on electricity, magnetism, matter, and energy was presented to generate interest and prepare users to understand data from a fusion experiment. Initially, users were allowed to analyze real-time and archival data from the Tokamak Fusion Test Reactor (TFTR) experiment. IPPEX won numerous awards for its novel approach of allowing users to participate in ongoing research. However, the latest revisions of IPPEX were in 2001 and the interactive material is no longer functional on modern browsers. Also, access to real-time data was lost when TFTR was shut down. The interactive material on IPPEX is being rewritten in ActionScript3.0, and real-time and archival data from the National Spherical Tokamak Experiment (NSTX) will be made available to users. New tools like EFIT animations, fast cameras, and plots of important plasma parameters will be included along with an existing Java-based ``virtual tokamak.'' Screenshots from the upgraded website and future directions will be presented.

76 FR 72902 - Materials Processing Equipment Technical Advisory Committee;

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-28

... DEPARTMENT OF COMMERCE Bureau of Industry and Security Materials Processing Equipment Technical Advisory Committee; Notice of Partially Closed Meeting The Materials Processing Equipment Technical... questions that affect the level of export controls applicable to materials processing equipment and related...

Novel spinal instrumentation to enhance osteogenesis and fusion: a preliminary study.

PubMed

MacEwan, Matthew R; Talcott, Michael R; Moran, Daniel W; Leuthardt, Eric C

2016-09-01

OBJECTIVE Instrumented spinal fusion continues to exhibit high failure rates in patients undergoing multilevel lumbar fusion or pseudarthrosis revision; with Grade II or higher spondylolisthesis; or in those possessing risk factors such as obesity, tobacco use, or metabolic disorders. Direct current (DC) electrical stimulation of bone growth represents a unique surgical adjunct in vertebral fusion procedures, yet existing spinal fusion stimulators are not optimized to enhance interbody fusion. To develop an advanced method of applying DC electrical stimulation to promote interbody fusion, a novel osteogenic spinal system capable of routing DC through rigid instrumentation and into the vertebral bodies was fabricated. A pilot study was designed to assess the feasibility of osteogenic instrumentation and compare the ability of osteogenic instrumentation to promote successful interbody fusion in vivo to standard spinal instrumentation with autograft. METHODS Instrumented, single-level, posterior lumbar interbody fusion (PLIF) with autologous graft was performed at L4-5 in adult Toggenburg/Alpine goats, using both osteogenic spinal instrumentation (plus electrical stimulation) and standard spinal instrumentation (no electrical stimulation). At terminal time points (3 months, 6 months), animals were killed and lumbar spines were explanted for radiographic analysis using a SOMATOM Dual Source Definition CT Scanner and high-resolution Microcat II CT Scanner. Trabecular continuity, radiodensity within the fusion mass, and regional bone formation were examined to determine successful spinal fusion. RESULTS Quantitative analysis of average bone density in pedicle screw beds confirmed that electroactive pedicle screws used in the osteogenic spinal system focally enhanced bone density in instrumented vertebral bodies. Qualitative and quantitative analysis of high-resolution CT scans of explanted lumbar spines further demonstrated that the osteogenic spinal system induced solid bony fusion across the L4-5 disc space as early as 6 weeks postoperatively. In comparison, inactive spinal instrumentation with autograft was unable to promote successful interbody fusion by 6 months postoperatively. CONCLUSIONS Results of this study demonstrate that novel osteogenic spinal instrumentation supports interbody fusion through the focal delivery of DC electrical stimulation. With further technical development and scientific/clinical validation, osteogenic spinal instrumentation may offer a unique alternative to biological scaffolds and pharmaceutical adjuncts used in spinal fusion procedures.

Review of Two-Stage FEL Research at KMS Fusion.

DTIC Science & Technology

1983-01-21

vi ty Research and Engineering Technical Library (3 copies) NST. Station, MS 39529 Information Office Library Branch The Pentagon Naval Explosive ...Shafer Associates, Inc. Office of Naval Research 10 Lakeside Office Park Arlington, VA 22217 Wakefield, MA 01880 Dr. Don Prosnitz Dr. T. C. Marshall

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldsmith, M.W.; Forbes, I.A.; Turnage, J.C.

The potential of new and future energy technologies is discussed, with information provided on availability, technical and economic feasibility, and limitations due to the form of the energy. Energy sources not presently in use (i.e., shale oil, garbage, geothermal, wind, tidal, breeder reactors, ocean thermal gradients, solar energy, and fusion) are expected to supply only 10 to 15% of the Nation's energy requirements in the year 2000. The following chapters are included: Energy Use and Supply; Extending Chemical Fuel Resources, which covers oil shale and tar sands, coal gasification and liquefaction, garbage, and biomass energy; Harnessing the Forces of Nature,more » which describes geothermal, tidal, hydro, wind, and solar energy; New Nuclear Technology (e.g., converter reactors, breeder reactors, fusion by magnetic confinement, and laser fusion); and Improving Energy Production Efficiency, with discussions on energy storage, MHD (magnetohydrodynamics), and combined cycles. (64 references) (BYB)« less

Spallation as a dominant source of pusher-fuel and hot-spot mix in inertial confinement fusion capsules

DOE PAGES

Orth, Charles D.

2016-02-23

We suggest that a potentially dominant but previously neglected source of pusher-fuel and hot-spot “mix” may have been the main degradation mechanism for fusion energy yields of modern inertial confinement fusion (ICF) capsules designed and fielded to achieve high yields — not hydrodynamic instabilities. This potentially dominant mix source is the spallation of small chunks or “grains” of pusher material into the fuel regions whenever (1) the solid material adjacent to the fuel changes its phase by nucleation, and (2) this solid material spalls under shock loading and sudden decompression. Finally, we describe this mix mechanism, support it with simulationsmore » and experimental evidence, and explain how to eliminate it and thereby allow higher yields for ICF capsules and possibly ignition at the National Ignition Facility.« less

Image fusion and navigation platforms for percutaneous image-guided interventions.

PubMed

Rajagopal, Manoj; Venkatesan, Aradhana M

2016-04-01

Image-guided interventional procedures, particularly image guided biopsy and ablation, serve an important role in the care of the oncology patient. The need for tumor genomic and proteomic profiling, early tumor response assessment and confirmation of early recurrence are common scenarios that may necessitate successful biopsies of targets, including those that are small, anatomically unfavorable or inconspicuous. As image-guided ablation is increasingly incorporated into interventional oncology practice, similar obstacles are posed for the ablation of technically challenging tumor targets. Navigation tools, including image fusion and device tracking, can enable abdominal interventionalists to more accurately target challenging biopsy and ablation targets. Image fusion technologies enable multimodality fusion and real-time co-displays of US, CT, MRI, and PET/CT data, with navigational technologies including electromagnetic tracking, robotic, cone beam CT, optical, and laser guidance of interventional devices. Image fusion and navigational platform technology is reviewed in this article, including the results of studies implementing their use for interventional procedures. Pre-clinical and clinical experiences to date suggest these technologies have the potential to reduce procedure risk, time, and radiation dose to both the patient and the operator, with a valuable role to play for complex image-guided interventions.

Scale Estimation and Correction of the Monocular Simultaneous Localization and Mapping (SLAM) Based on Fusion of 1D Laser Range Finder and Vision Data.

PubMed

Zhang, Zhuang; Zhao, Rujin; Liu, Enhai; Yan, Kun; Ma, Yuebo

2018-06-15

This article presents a new sensor fusion method for visual simultaneous localization and mapping (SLAM) through integration of a monocular camera and a 1D-laser range finder. Such as a fusion method provides the scale estimation and drift correction and it is not limited by volume, e.g., the stereo camera is constrained by the baseline and overcomes the limited depth range problem associated with SLAM for RGBD cameras. We first present the analytical feasibility for estimating the absolute scale through the fusion of 1D distance information and image information. Next, the analytical derivation of the laser-vision fusion is described in detail based on the local dense reconstruction of the image sequences. We also correct the scale drift of the monocular SLAM using the laser distance information which is independent of the drift error. Finally, application of this approach to both indoor and outdoor scenes is verified by the Technical University of Munich dataset of RGBD and self-collected data. We compare the effects of the scale estimation and drift correction of the proposed method with the SLAM for a monocular camera and a RGBD camera.

Remotely controlled fusion of selected vesicles and living cells: a key issue review

NASA Astrophysics Data System (ADS)

Bahadori, Azra; Moreno-Pescador, Guillermo; Oddershede, Lene B.; Bendix, Poul M.

2018-03-01

Remote control over fusion of single cells and vesicles has a great potential in biological and chemical research allowing both transfer of genetic material between cells and transfer of molecular content between vesicles. Membrane fusion is a critical process in biology that facilitates molecular transport and mixing of cellular cytoplasms with potential formation of hybrid cells. Cells precisely regulate internal membrane fusions with the aid of specialized fusion complexes that physically provide the energy necessary for mediating fusion. Physical factors like membrane curvature, tension and temperature, affect biological membrane fusion by lowering the associated energy barrier. This has inspired the development of physical approaches to harness the fusion process at a single cell level by using remotely controlled electromagnetic fields to trigger membrane fusion. Here, we critically review various approaches, based on lasers or electric pulses, to control fusion between individual cells or between individual lipid vesicles and discuss their potential and limitations for present and future applications within biochemistry, biology and soft matter.

Analysis of Muon Induced Neutrons in Detecting High Z Nuclear Materials

DTIC Science & Technology

2015-03-01

mass distributions, delayed fission probabilities, and prompt to delayed fission ratios [16]. 10 2.3 Muon Catalyzed Fusion Fusion occurs when two light ...proton number; A is the atomic mass; ⇢ is the material density; = v/c where v is the velocity of the particle and c is the speed of light ; is the...8217) %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 81 % Combine all neutron events time stamps into one vector %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% timeindex of

Technology Base Seminar Wargame 2 (TBSWG 2). Volume 1. Summary Report

DTIC Science & Technology

1990-11-16

nuclear, biological and chemical (NBC) and ballistic protection without reducing soldier mobility . Training and rehearsal systems will allow the...7 KNOW WHERE THE ENEMY IS ALL THE TIME SENSOR FIDEUTY INFORMATION FUSION 3 RANGE OF COMMO 4 RANGE OF FIRES S PRECISION MUNITIONS 6 RAPID MOBILITY 7...and .nfo Precision Problems and TECNOLOGIES Fusion) Fires Mobility Advanced Materials/ Material Processing 0) Advanced Propulsion Advanced Signal

An overview of research activities on materials for nuclear applications at the INL Safety, Tritium and Applied Research facility

NASA Astrophysics Data System (ADS)

Calderoni, P.; Sharpe, J.; Shimada, M.; Denny, B.; Pawelko, B.; Schuetz, S.; Longhurst, G.; Hatano, Y.; Hara, M.; Oya, Y.; Otsuka, T.; Katayama, K.; Konishi, S.; Noborio, K.; Yamamoto, Y.

2011-10-01

The Safety, Tritium and Applied Research facility at the Idaho National Laboratory is a US Department of Energy National User Facility engaged in various aspects of materials research for nuclear applications related to fusion and advanced fission systems. Research activities are mainly focused on the interaction of tritium with materials, in particular plasma facing components, liquid breeders, high temperature coolants, fuel cladding, cooling and blanket structures and heat exchangers. Other activities include validation and verification experiments in support of the Fusion Safety Program, such as beryllium dust reactivity and dust transport in vacuum vessels, and support of Advanced Test Reactor irradiation experiments. This paper presents an overview of the programs engaged in the activities, which include the US-Japan TITAN collaboration, the US ITER program, the Next Generation Power Plant program and the tritium production program, and a presentation of ongoing experiments as well as a summary of recent results with emphasis on fusion relevant materials.

Initial results of the FUSION-X-US prototype combining 3D automated breast ultrasound and digital breast tomosynthesis.

PubMed

Schaefgen, Benedikt; Heil, Joerg; Barr, Richard G; Radicke, Marcus; Harcos, Aba; Gomez, Christina; Stieber, Anne; Hennigs, André; von Au, Alexandra; Spratte, Julia; Rauch, Geraldine; Rom, Joachim; Schütz, Florian; Sohn, Christof; Golatta, Michael

2018-06-01

To determine the feasibility of a prototype device combining 3D-automated breast ultrasound (ABVS) and digital breast tomosynthesis in a single device to detect and characterize breast lesions. In this prospective feasibility study, the FUSION-X-US prototype was used to perform digital breast tomosynthesis and ABVS in 23 patients with an indication for tomosynthesis based on current guidelines after clinical examination and standard imaging. The ABVS and tomosynthesis images of the prototype were interpreted separately by two blinded experts. The study compares the detection and BI-RADS® scores of breast lesions using only the tomosynthesis and ABVS data from the FUSION-X-US prototype to the results of the complete diagnostic workup. Image acquisition and processing by the prototype was fast and accurate, with some limitations in ultrasound coverage and image quality. In the diagnostic workup, 29 solid lesions (23 benign, including three cases with microcalcifications, and six malignant lesions) were identified. Using the prototype, all malignant lesions were detected and classified as malignant or suspicious by both investigators. Solid breast lesions can be localized accurately and fast by the Fusion-X-US system. Technical improvements of the ultrasound image quality and ultrasound coverage are needed to further study this new device. The prototype combines tomosynthesis and automated 3D-ultrasound (ABVS) in one device. It allows accurate detection of malignant lesions, directly correlating tomosynthesis and ABVS data. The diagnostic evaluation of the prototype-acquired data was interpreter-independent. The prototype provides a time-efficient and technically reliable diagnostic procedure. The combination of tomosynthesis and ABVS is a promising diagnostic approach.

Cone beam computed tomography images fusion in predicting lung ablation volumes: a feasibility study.

PubMed

Ierardi, Anna Maria; Petrillo, Mario; Xhepa, Genti; Laganà, Domenico; Piacentino, Filippo; Floridi, Chiara; Duka, Ejona; Fugazzola, Carlo; Carrafiello, Gianpaolo

2016-02-01

Recently different software with the ability to plan ablation volumes have been developed in order to minimize the number of attempts of positioning electrodes and to improve a safe overall tumor coverage. To assess the feasibility of three-dimensional cone beam computed tomography (3D CBCT) fusion imaging with "virtual probe" positioning, to predict ablation volume in lung tumors treated percutaneously. Pre-procedural computed tomography contrast-enhanced scans (CECT) were merged with a CBCT volume obtained to plan the ablation. An offline tumor segmentation was performed to determine the number of antennae and their positioning within the tumor. The volume of ablation obtained, evaluated on CECT performed after 1 month, was compared with the pre-procedural predicted one. Feasibility was assessed on the basis of accuracy evaluation (visual evaluation [VE] and quantitative evaluation [QE]), technical success (TS), and technical effectiveness (TE). Seven of the patients with lung tumor treated by percutaneous thermal ablation were selected and treated on the basis of the 3D CBCT fusion imaging. In all cases the volume of ablation predicted was in accordance with that obtained. The difference in volume between predicted ablation volumes and obtained ones on CECT at 1 month was 1.8 cm(3) (SD ± 2, min. 0.4, max. 0.9) for MW and 0.9 cm(3) (SD ± 1.1, min. 0.1, max. 0.7) for RF. Use of pre-procedural 3D CBCT fusion imaging could be useful to define expected ablation volumes. However, more patients are needed to ensure stronger evidence. © The Foundation Acta Radiologica 2015.

75 FR 47546 - Materials Processing Equipment; Technical Advisory Committee; Notice of Partially Closed Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-06

... questions that affect the level of export controls applicable to materials processing equipment and related... DEPARTMENT OF COMMERCE Bureau of Industry and Security Materials Processing Equipment; Technical Advisory Committee; Notice of Partially Closed Meeting The Materials Processing Equipment Technical...

75 FR 66356 - Materials Processing Equipment Technical Advisory Committee; Notice of Partially Closed Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-28

... questions that affect the level of export controls applicable to materials processing equipment and related... DEPARTMENT OF COMMERCE Bureau of Industry and Security Materials Processing Equipment Technical Advisory Committee; Notice of Partially Closed Meeting The Materials Processing Equipment Technical...

78 FR 13625 - Materials Processing Equipment Technical Advisory Committee; Notice of Partially Closed Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-28

... questions that affect the level of export controls applicable to materials processing equipment and related... DEPARTMENT OF COMMERCE Bureau of Industry and Security Materials Processing Equipment Technical Advisory Committee; Notice of Partially Closed Meeting The Materials Processing Equipment Technical...

77 FR 65857 - Materials Processing Equipment Technical Advisory Committee; Notice of Partially Closed Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-31

... questions that affect the level of export controls applicable to materials processing equipment and related... DEPARTMENT OF COMMERCE Bureau of Industry and Security Materials Processing Equipment Technical Advisory Committee; Notice of Partially Closed Meeting The Materials Processing Equipment Technical...

76 FR 20949 - Materials Processing Equipment Technical Advisory Committee; Notice of Partially Closed Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-14

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DOE Office of Scientific and Technical Information (OSTI.GOV)

None

The vision described here builds on the present U.S. activities in fusion plasma and materials science relevant to the energy goal and extends plasma science at the frontier of discovery. The plan is founded on recommendations made by the National Academies, a number of recent studies by the Fusion Energy Sciences Advisory Committee (FESAC), and the Administration’s views on the greatest opportunities for U.S. scientific leadership.This report highlights five areas of critical importance for the U.S. fusion energy sciences enterprise over the next decade: 1) Massively parallel computing with the goal of validated whole-fusion-device modeling will enable a transformation inmore » predictive power, which is required to minimize risk in future fusion energy development steps; 2) Materials science as it relates to plasma and fusion sciences will provide the scientific foundations for greatly improved plasma confinement and heat exhaust; 3) Research in the prediction and control of transient events that can be deleterious to toroidal fusion plasma confinement will provide greater confidence in machine designs and operation with stable plasmas; 4) Continued stewardship of discovery in plasma science that is not expressly driven by the energy goal will address frontier science issues underpinning great mysteries of the visible universe and help attract and retain a new generation of plasma/fusion science leaders; 5) FES user facilities will be kept world-leading through robust operations support and regular upgrades. Finally, we will continue leveraging resources among agencies and institutions and strengthening our partnerships with international research facilities.« less

Method for mounting laser fusion targets for irradiation

DOEpatents

Fries, R. Jay; Farnum, Eugene H.; McCall, Gene H.

1977-07-26

Methods for preparing laser fusion targets of the ball-and-disk type are disclosed. Such targets are suitable for irradiation with one or two laser beams to produce the requisite uniform compression of the fuel material.

Computational modeling of joint U.S.-Russian experiments relevant to magnetic compression/magnetized target fusion (MAGO/MTF)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sheehey, P.T.; Faehl, R.J.; Kirkpatrick, R.C.

1997-12-31

Magnetized Target Fusion (MTF) experiments, in which a preheated and magnetized target plasma is hydrodynamically compressed to fusion conditions, present some challenging computational modeling problems. Recently, joint experiments relevant to MTF (Russian acronym MAGO, for Magnitnoye Obzhatiye, or magnetic compression) have been performed by Los Alamos National Laboratory and the All-Russian Scientific Research Institute of Experimental Physics (VNIIEF). Modeling of target plasmas must accurately predict plasma densities, temperatures, fields, and lifetime; dense plasma interactions with wall materials must be characterized. Modeling of magnetically driven imploding solid liners, for compression of target plasmas, must address issues such as Rayleigh-Taylor instability growthmore » in the presence of material strength, and glide plane-liner interactions. Proposed experiments involving liner-on-plasma compressions to fusion conditions will require integrated target plasma and liner calculations. Detailed comparison of the modeling results with experiment will be presented.« less

Cryogenic electrical properties of irradiated cyanate ester/epoxy insulation for fusion magnets

NASA Astrophysics Data System (ADS)

Li, X.; Wu, Z. X.; Li, J.; Xu, D.; Liu, H. M.; Huang, R. J.; Li, L. F.

2017-12-01

The insulation materials used in high field fusion magnets require excellent mechanical properties, high electrical breakdown strength, good thermal conductivity and high radiation tolerance. Previous investigations showed that cyanate ester/epoxy (CE/EP) insulation material, a candidate insulation for fusion magnets, can maintain good mechanical performance at cryogenic temperature after 10 MGy irradiation and has a much longer pot life than traditional epoxy insulation material. In order to quantify the electrical properties of the CE/EP insulation material at low temperature, a cryogenic electrical property testing system cooled by a G-M cryocooler was developed for this study. An insulation material with 40% cyanate ester and 60% epoxy was subjected to 60Co γ-ray irradiation in air at ambient temperature with a dose rate of 300 Gy/min, and total doses of 1 MGy, 5 MGy and 10 MGy. The electrical breakdown strength of this CE/EP insulation material was measured before and after irradiation. The results show that cryogenic temperature has a positive effect on the electrical breakdown strength of this composite, while the influence of 60Co γ-ray irradiation is not obvious at 6.1 K.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stelson, P.H.

The bulk of the Division's effort concerned nuclear physics and accelerator development, but work in the areas of nuclear data, research applicable to the magnetic fusion project, atomic and molecular physics, and high-energy physics is also recounted. Lists of publications, technical talks, personnel, etc., are included. Individual reports with sufficient data are abstracted separately. (RWR)

Inertial Fusion Energy reactor design studies: Prometheus-L, Prometheus-H. Volume 2, Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Waganer, L.M.; Driemeyer, D.E.; Lee, V.D.

1992-03-01

This report contains a review of design studies for Inertial Confinement reactor. This second of three volumes discussions is some detail the following: Objectives, requirements, and assumptions; rationale for design option selection; key technical issues and R&D requirements; and conceptual design selection and description.

76 FR 3612 - Materials Technical Advisory Committee; Notice of Partially Closed Meeting

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SNARE-mediated membrane fusion in autophagy.

PubMed

Wang, Yongyao; Li, Linsen; Hou, Chen; Lai, Ying; Long, Jiangang; Liu, Jiankang; Zhong, Qing; Diao, Jiajie

2016-12-01

Autophagy, a conserved self-eating process for the bulk degradation of cytoplasmic materials, involves double-membrane autophagosomes formed when an isolation membrane emerges and their direct fusion with lysosomes for degradation. For the early biogenesis of autophagosomes and their later degradation in lysosomes, membrane fusion is necessary, although different sets of genes and autophagy-related proteins involved in distinct fusion steps have been reported. To clarify the molecular mechanism of membrane fusion in autophagy, to not only expand current knowledge of autophagy, but also benefit human health, this review discusses key findings that elucidate the unique membrane dynamics of autophagy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Occipitocervical fusions in children. Retrospective analysis and technical considerations.

PubMed

Rodgers, W B; Coran, D L; Emans, J B; Hresko, M T; Hall, J E

1999-07-01

This report presents a retrospective analysis of the authors' experience with occipitocervical fusions in children and adolescents during the last 2 decades. A description of an operative technique devised by the senior author (JEH), and a comparison of the results using this and other methods of fusion are given. Twenty-three patients underwent occipitocervical fusion. Fifteen of the patients were operated on using the authors' technique. To achieve stable fixation of the distal cervical vertebra a threaded Kirschner wire was passed transversely through the spinous process; occipital fixation was achieved by the traditional method of wiring corticocancellous bone graft to the skull through burr holes. The occipital wires then were wrapped around the Kirschner wire and the graft was cradled in the resulting nest. Halo immobilization was used in 10 patients for an average of 12.5 weeks (range, 6-24 weeks). Twenty-two patients achieved successful fusion at an average followup of 5.8 years (range, 1-14.33 years). Several complications, including transient quadriplegia in one patient, pseudarthrosis in two (one of which persists), hardware fixation failure in one, unintended distal extension of the fusion, pneumonia, wound infection, halo pin infection, skin breakdown under the halo vest, hydrocephalus, cerebrospinal fluid leak, and traumatic fusion fracture were encountered. Results using the technique described herein are comparable with or better than the results reported in the previous literature, and the results of the patients in this series in whom the technique was not used.

Magnetized Target Fusion

NASA Technical Reports Server (NTRS)

Griffin, Steven T.

2002-01-01

Magnetized target fusion (MTF) is under consideration as a means of building a low mass, high specific impulse, and high thrust propulsion system for interplanetary travel. This unique combination is the result of the generation of a high temperature plasma by the nuclear fusion process. This plasma can then be deflected by magnetic fields to provide thrust. Fusion is initiated by a small traction of the energy generated in the magnetic coils due to the plasma's compression of the magnetic field. The power gain from a fusion reaction is such that inefficiencies due to thermal neutrons and coil losses can be overcome. Since the fusion reaction products are directly used for propulsion and the power to initiate the reaction is directly obtained from the thrust generation, no massive power supply for energy conversion is required. The result should be a low engine mass, high specific impulse and high thrust system. The key is to successfully initiate fusion as a proof-of-principle for this application. Currently MSFC is implementing MTF proof-of-principle experiments. This involves many technical details and ancillary investigations. Of these, selected pertinent issues include the properties, orientation and timing of the plasma guns and the convergence and interface development of the "pusher" plasma. Computer simulations of the target plasma's behavior under compression and the convergence and mixing of the gun plasma are under investigation. This work is to focus on the gun characterization and development as it relates to plasma initiation and repeatability.

High-accuracy 3-D modeling of cultural heritage: the digitizing of Donatello's "Maddalena".

PubMed

Guidi, Gabriele; Beraldin, J Angelo; Atzeni, Carlo

2004-03-01

Three-dimensional digital modeling of Heritage works of art through optical scanners, has been demonstrated in recent years with results of exceptional interest. However, the routine application of three-dimensional (3-D) modeling to Heritage conservation still requires the systematic investigation of a number of technical problems. In this paper, the acquisition process of the 3-D digital model of the Maddalena by Donatello, a wooden statue representing one of the major masterpieces of the Italian Renaissance which was swept away by the Florence flood of 1966 and successively restored, is described. The paper reports all the steps of the acquisition procedure, from the project planning to the solution of the various problems due to range camera calibration and to material non optically cooperative. Since the scientific focus is centered on the 3-D model overall dimensional accuracy, a methodology for its quality control is described. Such control has demonstrated how, in some situations, the ICP-based alignment can lead to incorrect results. To circumvent this difficulty we propose an alignment technique based on the fusion of ICP with close-range digital photogrammetry and a non-invasive procedure in order to generate a final accurate model. In the end detailed results are presented, demonstrating the improvement of the final model, and how the proposed sensor fusion ensure a pre-specified level of accuracy.

Radiation effect of neutrons produced by D-D side reactions on a D-3He fusion reactor

NASA Astrophysics Data System (ADS)

Bahmani, J.

2017-04-01

One of the most important characteristics in D-3He fusion reactors is neutron production via D-D side reactions. The neutrons can activate structural material, degrading them and ultimately converting them into high-level radioactive waste, while it is really costly and difficult to remove them. The neutrons from a fusion reactor could also be used to make weapons-grade nuclear material, rendering such types of fusion reactors a serious proliferation hazard. A related problem is the presence of radioactive elements such as tritium in D-3He plasma, either as fuel for or as products of the nuclear reactions; substantial quantities of radioactive elements would not only pose a general health risk, but tritium in particular would also be another proliferation hazard. The problems of neutron radiation and radioactive element production are especially interconnected because both would result from the D-D side reaction. Therefore, the presentation approach for reducing neutrons via D-D nuclear side reactions in a D-3He fusion reactor is very important. For doing this research, energy losses and neutron power fraction in D-3He fusion reactors are investigated. Calculations show neutrons produced by the D-D nuclear side reaction could be reduced by changing to a more 3He-rich fuel mixture, but then the bremsstrahlung power loss fraction would increase in the D-3He fusion reactor.

Calculation of Excitation Function of Some Structural Fusion Material for (n, p) Reactions up to 25 MeV

NASA Astrophysics Data System (ADS)

Reshid, Tarik S.

2013-04-01

Fusion serves an inexhaustible energy for humankind. Although there have been significant research and development studies on the inertial and magnetic fusion reactor technology, Furthermore, there are not radioactive nuclear waste problems in the fusion reactors. In this study, (n, p) reactions for some structural fusion materials such as 27Al, 51V, 52Cr, 55Mn and 56Fe have been investigated. The new calculations on the excitation functions of 27 Al(n, p) 27 Mg, 51 V(n, p) 51 Ti, 52 Cr(n, p) 52 V, 55 Mn(n, p) 55 Cr and 56 Fe(n, p) 56 Mn reactions have been carried out up to 30 MeV incident neutron energy. Statistical model calculations, based on the Hauser-Feshbach formalism, have been carried out using the TALYS-1.0 and were compared with available experimental data in the literature and with ENDF/B-VII, T = 300 K; JENDL-3.3, T = 300 K and JEFF-3.1, T = 300 K evaluated libraries.

Fusion technologies for Laser Inertial Fusion Energy (LIFE)

NASA Astrophysics Data System (ADS)

Kramer, K. J.; Latkowski, J. F.; Abbott, R. P.; Anklam, T. P.; Dunne, A. M.; El-Dasher, B. S.; Flowers, D. L.; Fluss, M. J.; Lafuente, A.; Loosmore, G. A.; Morris, K. R.; Moses, E.; Reyes, S.

2013-11-01

The Laser Inertial Fusion-based Energy (LIFE) engine design builds upon on going progress at the National Ignition Facility (NIF) and offers a near-term pathway to commercial fusion. Fusion technologies that are critical to success are reflected in the design of the first wall, blanket and tritium separation subsystems. The present work describes the LIFE engine-related components and technologies. LIFE utilizes a thermally robust indirect-drive target and a chamber fill gas. Coolant selection and a large chamber solid-angle coverage provide ample tritium breeding margin and high blanket gain. Target material selection eliminates the need for aggressive chamber clearing, while enabling recycling. Demonstrated tritium separation and storage technologies limit the site tritium inventory to attractive levels. These key technologies, along with the maintenance and advanced materials qualification program have been integrated into the LIFE delivery plan. This describes the development of components and subsystems, through prototyping and integration into a First Of A Kind power plant. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

76 FR 21331 - Materials Technical Advisory Committee; Notice of Partially Closed Meeting

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2011-04-15

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Repetition rates in heavy ion beam driven fusion reactors

NASA Astrophysics Data System (ADS)

Peterson, Robert R.

1986-01-01

The limits on the cavity gas density required for beam propagation and condensation times for material vaporized by target explosions can determine the maximum repetition rate of Heavy Ion Beam (HIB) driven fusion reactors. If the ions are ballistically focused onto the target, the cavity gas must have a density below roughly 10-4 torr (3×1012 cm-3) at the time of propagation; other propagation schemes may allow densities as high as 1 torr or more. In some reactor designs, several kilograms of material may be vaporized off of the target chamber walls by the target generated x-rays, raising the average density in the cavity to 100 tor or more. A one-dimensional combined radiation hydrodynamics and vaporization and condensation computer code has been used to simulate the behavior of the vaporized material in the target chambers of HIB fusion reactors.

Baseline high heat flux and plasma facing materials for fusion

NASA Astrophysics Data System (ADS)

Ueda, Y.; Schmid, K.; Balden, M.; Coenen, J. W.; Loewenhoff, Th.; Ito, A.; Hasegawa, A.; Hardie, C.; Porton, M.; Gilbert, M.

2017-09-01

In fusion reactors, surfaces of plasma facing components (PFCs) are exposed to high heat and particle flux. Tungsten and Copper alloys are primary candidates for plasma facing materials (PFMs) and coolant tube materials, respectively, mainly due to high thermal conductivity and, in the case of tungsten, its high melting point. In this paper, recent understandings and future issues on responses of tungsten and Cu alloys to fusion environments (high particle flux (including T and He), high heat flux, and high neutron doses) are reviewed. This review paper includes; Tritium retention in tungsten (K. Schmid and M. Balden), Impact of stationary and transient heat loads on tungsten (J.W. Coenen and Th. Loewenhoff), Helium effects on surface morphology of tungsten (Y. Ueda and A. Ito), Neutron radiation effects in tungsten (A. Hasegawa), and Copper and copper alloys development for high heat flux components (C. Hardie, M. Porton, and M. Gilbert).

Research Needs for Fusion-Fission Hybrid Systems. Report of the Research Needs Workshop (ReNeW) Gaithersburg, Maryland, September 30 - October 2, 2009

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

Largely in anticipation of a possible nuclear renaissance, there has been an enthusiastic renewal of interest in the fusion-fission hybrid concept, driven primarily by some members of the fusion community. A fusion-fission hybrid consists of a neutron-producing fusion core surrounded by a fission blanket. Hybrids are of interest because of their potential to address the main long-term sustainability issues related to nuclear power: fuel supply, energy production, and waste management. As a result of this renewed interest, the U.S. Department of Energy (DOE), with the participation of the Office of Fusion Energy Sciences (OFES), Office of Nuclear Energy (NE), andmore » National Nuclear Security Administration (NNSA), organized a three-day workshop in Gaithersburg, Maryland, from September 30 through October 2, 2009. Participants identified several goals. At the highest level, it was recognized that DOE does not currently support any R&D in the area of fusion-fission hybrids. The question to be addressed was whether or not hybrids offer sufficient promise to motivate DOE to initiate an R&D program in this area. At the next level, the workshop participants were asked to define the research needs and resources required to move the fusion-fission concept forward. The answer to the high-level question was given in two ways. On the one hand, when viewed as a standalone concept, the fusion-fission hybrid does indeed offer the promise of being able to address the sustainability issues associated with conventional nuclear power. On the other hand, when participants were asked whether these hybrid solutions are potentially more attractive than contemplated pure fission solutions (that is, fast burners and fast breeders), there was general consensus that this question could not be quantitatively answered based on the known technical information. Pure fission solutions are based largely on existing both fusion and nuclear technology, thereby prohibiting a fair side-by-side comparison. Another important issue addressed at the conference was the time scale on which long-term sustainability issues must be solved. There was a wide diversity of opinion and no consensus was possible. One group, primarily composed of members of the fission community, argued that the present strategies with respect to waste management (on-site storage) and fuel supply (from natural uranium) would suffice for at least 50 years, with the main short-term problem being the economics of light water reactors (LWRs). Many from the fusion community believed that the problems, particularly waste management, were of a more urgent nature and that we needed to address them sooner rather than later. There was rigorous debate on all the issues before, during, and after the workshop. Based on this debate, the workshop participants developed a set of high-level Findings and Research Needs and a companion set of Technical Findings and Research Needs. In the context of the Executive Summary it is sufficient to focus on the high-level findings which are summarized.« less

A technique of fusion for failed total replacement of the ankle: tibio-allograft-calcaneal fusion with a locked retrograde intramedullary nail.

PubMed

Thomason, K; Eyres, K S

2008-07-01

Salvage of a failed total ankle replacement is technically challenging and although a revision procedure may be desirable, a large amount of bone loss or infection may preclude this. Arthrodesis can be difficult to achieve and is usually associated with considerable shortening of the limb. We describe a technique for restoring talar height using an allograft from the femoral head compressed by an intramedullary nail. Three patients with aseptic loosening were treated successfully by this method with excellent symptomatic relief at a mean follow-up of 32 months (13 to 50).

Gallium arsenide-gallium nitride wafer fusion and the n-aluminum gallium arsenide/p-gallium arsenide/n-gallium nitride double heterojunction bipolar transistor

NASA Astrophysics Data System (ADS)

Estrada, Sarah M.

This dissertation describes the n-AlGaAs/p-GaAs/n-GaN heterojunction bipolar transistor (HBT), the first transistor formed via wafer fusion. The fusion process was developed as a way to combine lattice-mismatched materials for high-performance electronic devices, not obtainable via conventional all-epitaxial formation methods. Despite the many challenges of wafer fusion, successful transistors were demonstrated and improved, via the optimization of material structure and fusion process conditions. Thus, this project demonstrated the integration of disparate device materials, chosen for their optimal electronic properties, unrestricted by the conventional (and very limiting) requirement of lattice-matching. By combining an AlGaAs-GaAs emitter-base with a GaN collector, the HBT benefited from the high breakdown voltage of GaN, and from the high emitter injection efficiency and low base transit time of AlGaAs-GaAs. Because the GaAs-GaN lattice mismatch precluded an all-epitaxial formation of the HBT, the GaAs-GaN heterostructure was formed via fusion. This project began with the development of a fusion process that formed mechanically robust and electrically active GaAs-GaN heterojunctions. During the correlation of device electrical performance with a systematic variation of fusion conditions over a wide range (500--750°C, 0.5--2hours), a mid-range fusion temperature was found to induce optimal HBT electrical performance. Transmission electron microscopy (TEM) and secondary ion mass spectrometry (SIMS) were used to assess possible reasons for the variations observed in device electrical performance. Fusion process conditions were correlated with electrical (I-V), structural (TEM), and chemical (SIMS) analyses of the resulting heterojunctions, in order to investigate the trade-off between increased interfacial disorder (TEM) with low fusion temperature and increased diffusion (SIMS) with high fusion temperature. The best do device results (IC ˜ 2.9 kA/cm2 and beta ˜ 3.5, at VCE = 20V and IB = 10mA) were obtained with an HBT formed via fusion at 600°C for 1 hour, with an optimized base-collector design. This was quite an improvement, as compared to an HBT with a simpler base-collector structure, also fused at 600°C for 1 hour (IC ˜ 0.83 kA/cm2 and beta ˜ 0.89, at VCE = 20V and IB = 10mA). Fused AlGaAs-GaAs-GaAs HBTs were compared to fused AlGaAs-GaAs-GaN HBTs, demonstrating that the use of a wider bandgap collector (Eg,GaN > Eg,GaAs) did indeed improve HBT performance at high applied voltages, as desired for high-power applications.

Safety and Environment aspects of Tokamak- type Fusion Power Reactor- An Overview

NASA Astrophysics Data System (ADS)

Doshi, Bharat; Reddy, D. Chenna

2017-04-01

Naturally occurring thermonuclear fusion reaction (of light atoms to form a heavier nucleus) in the sun and every star in the universe, releases incredible amounts of energy. Demonstrating the controlled and sustained reaction of deuterium-tritium plasma should enable the development of fusion as an energy source here on Earth. The promising fusion power reactors could be operated on the deuterium-tritium fuel cycle with fuel self-sufficiency. The potential impact of fusion power on the environment and the possible risks associated with operating large-scale fusion power plants is being studied by different countries. The results show that fusion can be a very safe and sustainable energy source. A fusion power plant possesses not only intrinsic advantages with respect to safety compared to other sources of energy, but also a negligible long term impact on the environment provided certain precautions are taken in its design. One of the important considerations is in the selection of low activation structural materials for reactor vessel. Selection of the materials for first wall and breeding blanket components is also important from safety issues. It is possible to fully benefit from the advantages of fusion energy if safety and environmental concerns are taken into account when considering the conceptual studies of a reactor design. The significant safety hazards are due to the tritium inventory and energetic neutron fluence induced activity in the reactor vessel, first wall components, blanket system etc. The potential of release of radioactivity under operational and accident conditions needs attention while designing the fusion reactor. Appropriate safety analysis for the quantification of the risk shall be done following different methods such as FFMEA (Functional Failure Modes and Effects Analysis) and HAZOP (Hazards and operability). Level of safety and safety classification such as nuclear safety and non-nuclear safety is very important for the FPR (Fusion Power Reactor). This paper describes an overview of safety and environmental merits of fusion power reactor, issues and design considerations and need for R&D on safety and environmental aspects of Tokamak type fusion reactor.

Improved Controls for Fusion RF Systems. Final technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Casey, Jeffrey A.

2011-11-08

We have addressed the specific requirements for the integrated systems controlling an array of klystrons used for Lower Hybrid Current Drive (LHCD). The immediate goal for our design was to modernize the transmitter protection system (TPS) for LHCD on the Alcator C-Mod tokamak at the MIT Plasma Science and Fusion Center (MIT-PSFC). Working with the Alcator C-Mod team, we have upgraded the design of these controls to retrofit for improvements in performance and safety, as well as to facilitate the upcoming expansion from 12 to 16 klystrons. The longer range goals to generalize the designs in such a way thatmore » they will be of benefit to other programs within the international fusion effort was met by designing a system which was flexible enough to address all the MIT system requirements, and modular enough to adapt to a large variety of other requirements with minimal reconfiguration.« less

Interstellar Travel without 'Magic'

NASA Astrophysics Data System (ADS)

Woodcock, G.

The possibility of interstellar space travel has become a popular subject. Distances of light years are an entirely new realm for human space travel. New means of propulsion are needed. Speculation about propulsion has included "magic", space warps, faster-than-light travel, known physics such as antimatter for which no practical implementation is known and also physics for which current research offers at least a hint of implementation, i.e. fusion. Performance estimates are presented for the latter and used to create vehicle concepts. Fusion propulsion will mean travel times of hundreds of years, so we adopt the "space colony" concepts of O'Neill as a ship design that could support a small civilization indefinitely; this provides the technical means. Economic reasoning is presented, arguing that development and production of "space colony" habitats for relief of Earth's population, with addition of fusion engines, will lead to vessels that can go interstellar. Scenarios are presented and a speculative estimate of a timetable is given.

Plasma Physics Network Newsletter, No. 3

NASA Astrophysics Data System (ADS)

1991-02-01

This issue of the Newsletter contains a report on the First South-North International Workshop on Fusion Theory, Tipaza, Algeria, 17-20 September, 1990; a report in the issuance of the 'Buenos Aires Memorandum' generated during the IV Latin American Workshop on Plasma Physics, Argentina, July 1990, and containing a proposal that the IFRC establish a 'Steering Committee on North-South Collaboration in Controlled Nuclear Fusion and Plasma Physics Research'; the announcement that the 14th International Conference on Plasma Physics and Controlled Nuclear Fusion will be held in Wuerzburg, Germany, September 30 to October 7, 1992; a list of IAEA technical committee meetings for 1991; an item on ITER news; an article 'Long Term Physics R and D Planning (for ITER)' by F. Engelmann; in the planned sequence of 'Reports on National Fusion Programs' contributions on the Chinese and Yugoslav programs; finally, the titles and contacts for two other newsletters of potential interest, i.e., the AAAPT (Asian African Association for Plasma Training) Newsletter, and the IPG (International physics Group-A sub unit of the American Physical Society) Newsletter.

Posterior spinal osteosynthesis for cervical fracture/dislocation using a flexible multistrand cable system: technical note.

PubMed

Huhn, S L; Wolf, A L; Ecklund, J

1991-12-01

Cervical instability secondary to fracture/dislocation or traumatic subluxation involving the posterior elements may be treated by a variety of fusion techniques. The rigidity of the stainless steel wires used in posterior cervical fusions often leads to difficulty with insertion, adequate tension, and conformation of the graft construct. This report describes a technique of posterior cervical fusion employing a wire system using flexible stainless steel cables. The wire consists of a flexible, 49-strand, stainless steel cable connected on one end to a short, malleable, blunt leader with the opposite end connected to a small islet. The cable may be used in occipitocervical, atlantoaxial, facet-to-spinous process, and interspinous fusion techniques. The cable loop is secured by using a tension/crimper device that sets the desired tension in the cable. In addition to superior biomechanical strength, the flexibility of the cable allows greater ease of insertion and tension adjustment. In terms of direct operative instrumentation in posterior cervical arthrodesis, involving both the upper and lower cervical spine, the cable system appears to be a safe and efficient alternative to monofilament wires.

Follow-up of negative MRI-targeted prostate biopsies: when are we missing cancer?

PubMed

Gold, Samuel A; Hale, Graham R; Bloom, Jonathan B; Smith, Clayton P; Rayn, Kareem N; Valera, Vladimir; Wood, Bradford J; Choyke, Peter L; Turkbey, Baris; Pinto, Peter A

2018-05-21

Multiparametric magnetic resonance imaging (mpMRI) has improved clinicians' ability to detect clinically significant prostate cancer (csPCa). Combining or fusing these images with the real-time imaging of transrectal ultrasound (TRUS) allows urologists to better sample lesions with a targeted biopsy (Tbx) leading to the detection of greater rates of csPCa and decreased rates of low-risk PCa. In this review, we evaluate the technical aspects of the mpMRI-guided Tbx procedure to identify possible sources of error and provide clinical context to a negative Tbx. A literature search was conducted of possible reasons for false-negative TBx. This includes discussion on false-positive mpMRI findings, termed "PCa mimics," that may incorrectly suggest high likelihood of csPCa as well as errors during Tbx resulting in inexact image fusion or biopsy needle placement. Despite the strong negative predictive value associated with Tbx, concerns of missed disease often remain, especially with MR-visible lesions. This raises questions about what to do next after a negative Tbx result. Potential sources of error can arise from each step in the targeted biopsy process ranging from "PCa mimics" or technical errors during mpMRI acquisition to failure to properly register MRI and TRUS images on a fusion biopsy platform to technical or anatomic limits on needle placement accuracy. A better understanding of these potential pitfalls in the mpMRI-guided Tbx procedure will aid interpretation of a negative Tbx, identify areas for improving technical proficiency, and improve both physician understanding of negative Tbx and patient-management options.

Quantitative multi-modal NDT data analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heideklang, René; Shokouhi, Parisa

2014-02-18

A single NDT technique is often not adequate to provide assessments about the integrity of test objects with the required coverage or accuracy. In such situations, it is often resorted to multi-modal testing, where complementary and overlapping information from different NDT techniques are combined for a more comprehensive evaluation. Multi-modal material and defect characterization is an interesting task which involves several diverse fields of research, including signal and image processing, statistics and data mining. The fusion of different modalities may improve quantitative nondestructive evaluation by effectively exploiting the augmented set of multi-sensor information about the material. It is the redundantmore » information in particular, whose quantification is expected to lead to increased reliability and robustness of the inspection results. There are different systematic approaches to data fusion, each with its specific advantages and drawbacks. In our contribution, these will be discussed in the context of nondestructive materials testing. A practical study adopting a high-level scheme for the fusion of Eddy Current, GMR and Thermography measurements on a reference metallic specimen with built-in grooves will be presented. Results show that fusion is able to outperform the best single sensor regarding detection specificity, while retaining the same level of sensitivity.« less

Nuclear and Physical Properties of Dielectrics under Neutron Irradiation in Fast (BN-600) and Fusion (DEMO-S) Reactors

NASA Astrophysics Data System (ADS)

Blokhin, D. A.; Chernov, V. M.; Blokhin, A. I.

2017-12-01

Nuclear and physical properties (activation and transmutation of elements) of BN and Al2O3 dielectric materials subjected to neutron irradiation for up to 5 years in Russian fast (BN-600) and fusion (DEMO-S) reactors were calculated using the ACDAM-2.0 software complex for different post-irradiation cooling times (up to 10 years). Analytical relations were derived for the calculated quantities. The results may be used in the analysis of properties of irradiated dielectric materials and may help establish the rules for safe handling of these materials.

Thermal and range fusion for a planetary rover

NASA Technical Reports Server (NTRS)

Caillas, Claude

1992-01-01

This paper describes how fusion between thermal and range imaging allows us to discriminate different types of materials in outdoor scenes. First, we analyze how pure vision segmentation algorithms applied to thermal images allow discriminating materials such as rock and sand. Second, we show how combining thermal and range information allows us to better discriminate rocks from sand. Third, as an application, we examine how an autonomous legged robot can use these techniques to explore other planets.

An Approach to the Reuse of Technical Materials for Educational Purposes

NASA Technical Reports Server (NTRS)

Levinstein, Irwin; Bryant, Wayne H. (Technical Monitor)

2001-01-01

This project addresses the problem of transforming technical documents intended for a technical audience into educational materials directed toward segments of the general public. In particular it addresses the conversion of technical material into Internet based educational materials. A major consideration of the project is the conservation of the time of subject matter experts in the organization in recognition of the fact that such experts are likely to be more valuable to the organization for purposes other than the production of educational outreach.

Preliminary Results Obtained in Integrated Safety Analysis of NASA Aviation Safety Program Technologies

NASA Technical Reports Server (NTRS)

2000-01-01

This is a quarterly listing of unclassified AGARD and RTO technical publications NASA received and announced in the NASA STI Database. Contents include 1) Sensor Data Fusion and Integration of the Human Element; 2) Planar Optical Measurement Methods for Gas Turbine Components; 3) RTO Highlights 1998, December 1998.

Spine interbody implants: material selection and modification, functionalization and bioactivation of surfaces to improve osseointegration.

PubMed

Rao, Prashanth J; Pelletier, Matthew H; Walsh, William R; Mobbs, Ralph J

2014-05-01

The clinical outcome of lumbar spinal fusion is correlated with achievement of bony fusion. Improving interbody implant bone on-growth and in-growth may enhance fusion, limiting pseudoarthrosis, stress shielding, subsidence and implant failure. Polyetheretherketone (PEEK) and titanium (Ti) are commonly selected for interbody spacer construction. Although these materials have desirable biocompatibility and mechanical properties, they require further modification to support osseointegration. Reports of extensive research on this topic are available in biomaterial-centric published reports; however, there are few clinical studies concerning surface modification of interbody spinal implants. The current article focuses on surface modifications aimed at fostering osseointegration from a clinician's point of view. Surface modification of Ti by creating rougher surfaces, modifying its surface topography (macro and nano), physical and chemical treatment and creating a porous material with high interconnectivity can improve its osseointegrative potential and bioactivity. Coating the surface with osteoconductive materials like hydroxyapatite (HA) can improve osseointegration. Because PEEK spacers are relatively inert, creating a composite by adding Ti or osteoconductive materials like HA can improve osseointegration. In addition, PEEK may be coated with Ti, effectively bio-activating the coating. © 2014 Chinese Orthopaedic Association and Wiley Publishing Asia Pty Ltd.

Finite Element Analysis of Interaction of Laser Beam with Material in Laser Metal Powder Bed Fusion Process.

PubMed

Fu, Guang; Zhang, David Z; He, Allen N; Mao, Zhongfa; Zhang, Kaifei

2018-05-10

A deep understanding of the laser-material interaction mechanism, characterized by laser absorption, is very important in simulating the laser metal powder bed fusion (PBF) process. This is because the laser absorption of material affects the temperature distribution, which influences the thermal stress development and the final quality of parts. In this paper, a three-dimensional finite element analysis model of heat transfer taking into account the effect of material state and phase changes on laser absorption is presented to gain insight into the absorption mechanism, and the evolution of instantaneous absorptance in the laser metal PBF process. The results showed that the instantaneous absorptance was significantly affected by the time of laser radiation, as well as process parameters, such as hatch space, scanning velocity, and laser power, which were consistent with the experiment-based findings. The applicability of this model to temperature simulation was demonstrated by a comparative study, wherein the peak temperature in fusion process was simulated in two scenarios, with and without considering the effect of material state and phase changes on laser absorption, and the simulated results in the two scenarios were then compared with experimental data respectively.

A rapid and efficient newly established method to detect COL1A1-PDGFB gene fusion in dermatofibrosarcoma protuberans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yokoyama, Yoko; Shimizu, Akira; Okada, Etsuko

Highlights: Black-Right-Pointing-Pointer We developed new method to rapidly identify COL1A1-PDGFB fusion in DFSP. Black-Right-Pointing-Pointer New PCR method using a single primer pair detected COL1A1-PDGFB fusion in DFSP. Black-Right-Pointing-Pointer This is the first report of DFSP with a novel COL1A1 breakpoint in exon 5. -- Abstract: The detection of fusion transcripts of the collagen type 1{alpha}1 (COL1A1) and platelet-derived growth factor-BB (PDGFB) genes by genetic analysis has recognized as a reliable and valuable molecular tool for the diagnosis of dermatofibrosarcoma protuberans (DFSP). To detect the COL1A1-PDGFB fusion, almost previous reports performed reverse transcription polymerase chain reaction (RT-PCR) using multiplex forward primersmore » from COL1A1. However, it has possible technical difficulties with respect to the handling of multiple primers and reagents in the procedure. The objective of this study is to establish a rapid, easy, and efficient one-step method of PCR using only a single primer pair to detect the fusion transcripts of the COL1A1 and PDGFB in DFSP. To validate new method, we compared the results of RT-PCR in five patients of DFSP between the previous method using multiplex primers and our established one-step RT-PCR using a single primer pair. In all cases of DFSP, the COL1A1-PDGFB fusion was detected by both previous method and newly established one-step PCR. Importantly, we detected a novel COL1A1 breakpoint in exon 5. The newly developed method is valuable to rapidly identify COL1A1-PDGFB fusion transcripts in DFSP.« less

Axial presacral lumbar interbody fusion and percutaneous posterior fixation for stabilization of lumbosacral isthmic spondylolisthesis.

PubMed

Gerszten, Peter C; Tobler, William; Raley, Thomas J; Miller, Larry E; Block, Jon E; Nasca, Richard J

2012-04-01

Case series. To describe a minimally invasive surgical technique for treatment of lumbosacral spondylolisthesis. Traditional surgical management of lumbosacral spondylolisthesis is technically challenging and associated with significant complications. Minimally invasive surgical techniques offer patients treatment alternatives with lower operative morbidity risk. The combination of percutaneous pedicle screw reduction and an axial presacral approach for lumbosacral discectomy and fusion is an option for the surgical management of low-grade lumbosacral spondylolisthesis. Twenty-six consecutive patients with symptomatic L5-S1 level isthmic spondylolisthesis (grade 1 or grade 2) underwent axial presacral lumbar interbody fusion and percutaneous posterior fixation. Study outcomes included visual analogue scale for axial pain severity, Odom criteria, and radiographic fusion. The procedure was successfully completed in all patients with no intraoperative complications reported. Intraoperative blood loss was minimal (range, 20-150 mL). Median hospital stay was 1 day (range, <1-2 d). Spondylolisthesis grade was improved after axial lumbar interbody fusion (P<0.001) with 50% (13 of 26) of patients showing a reduction of at least 1 grade. Axial pain severity improved from 8.1±1.4 at baseline to 2.8±2.3 after axial lumbar interbody fusion, representing a 66% reduction from baseline (95% confidence interval, 54.3%-77.9%). At 2-year posttreatment, all patients showed solid fusion. Using Odom criteria, 81% of patients were judged as excellent or good (16 excellent, 5 good, 3 fair, and 2 poor). There were no perioperative procedure-related complications including infection or bowel perforation. During postoperative follow-up, 4 patients required reintervention due to recurrent radicular (n=2) or screw-related (n=2) pain. The minimally invasive presacral axial interbody fusion and posterior instrumentation technique is a safe and effective treatment for low-grade isthmic spondylolisthesis.

Burning plasma regime for Fussion-Fission Research Facility

NASA Astrophysics Data System (ADS)

Zakharov, Leonid E.

2010-11-01

The basic aspects of burning plasma regimes of Fusion-Fission Research Facility (FFRF, R/a=4/1 m/m, Ipl=5 MA, Btor=4-6 T, P^DT=50-100 MW, P^fission=80-4000 MW, 1 m thick blanket), which is suggested as the next step device for Chinese fusion program, are presented. The mission of FFRF is to advance magnetic fusion to the level of a stationary neutron source and to create a technical, scientific, and technology basis for the utilization of high-energy fusion neutrons for the needs of nuclear energy and technology. FFRF will rely as much as possible on ITER design. Thus, the magnetic system, especially TFC, will take advantage of ITER experience. TFC will use the same superconductor as ITER. The plasma regimes will represent an extension of the stationary plasma regimes on HT-7 and EAST tokamaks at ASIPP. Both inductive discharges and stationary non-inductive Lower Hybrid Current Drive (LHCD) will be possible. FFRF strongly relies on new, Lithium Wall Fusion (LiWF) plasma regimes, the development of which will be done on NSTX, HT-7, EAST in parallel with the design work. This regime will eliminate a number of uncertainties, still remaining unresolved in the ITER project. Well controlled, hours long inductive current drive operation at P^DT=50-100 MW is predicted.

Fusion Energy Sciences Exascale Requirements Review. An Office of Science review sponsored jointly by Advanced Scientific Computing Research and Fusion Energy Sciences, January 27-29, 2016, Gaithersburg, Maryland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chang, Choong-Seock; Greenwald, Martin; Riley, Katherine

The additional computing power offered by the planned exascale facilities could be transformational across the spectrum of plasma and fusion research — provided that the new architectures can be efficiently applied to our problem space. The collaboration that will be required to succeed should be viewed as an opportunity to identify and exploit cross-disciplinary synergies. To assess the opportunities and requirements as part of the development of an overall strategy for computing in the exascale era, the Exascale Requirements Review meeting of the Fusion Energy Sciences (FES) community was convened January 27–29, 2016, with participation from a broad range ofmore » fusion and plasma scientists, specialists in applied mathematics and computer science, and representatives from the U.S. Department of Energy (DOE) and its major computing facilities. This report is a summary of that meeting and the preparatory activities for it and includes a wealth of detail to support the findings. Technical opportunities, requirements, and challenges are detailed in this report (and in the recent report on the Workshop on Integrated Simulation). Science applications are described, along with mathematical and computational enabling technologies. Also see http://exascaleage.org/fes/ for more information.« less

FOREWORD: 13th International Workshop on Plasma-Facing Materials and Components for Fusion Applications/1st International Conference on Fusion Energy Materials Science 13th International Workshop on Plasma-Facing Materials and Components for Fusion Applications/1st International Conference on Fusion Energy Materials Science

NASA Astrophysics Data System (ADS)

Jacob, Wolfgang; Linsmeier, Christian; Rubel, Marek

2011-12-01

The 13th International Workshop on Plasma-Facing Materials and Components (PFMC-13) jointly organized with the 1st International Conference on Fusion Energy Materials Science (FEMaS-1) was held in Rosenheim (Germany) on 9-13 May 2011. PFMC-13 is a successor of the International Workshop on Carbon Materials for Fusion Applications series. Between 1985 and 2003 ten 'Carbon Workshops' were organized in Jülich, Stockholm and Hohenkammer. Then it was time for a change and redefinition of the scope of the symposium to reflect the new requirements of ITER and the ongoing evolution in the field. Under the new name (PFMC-11), the workshop was first organized in 2006 in Greifswald, Germany and PFMC-12 took place in Jülich in 2009. Initially starting in 1985 with about 40 participants as a 1.5 day workshop, the event has continuously grown to about 220 participants at PFMC-12. Due to the joint organization with FEMaS-1, PFMC-13 set a new record with more than 280 participants. The European project Fusion Energy Materials Science, FEMaS, coordinated by the Max-Planck-Institut für Plasmaphysik (IPP), organizes and stimulates cooperative research activities which involve large-scale research facilities as well as other top-level materials characterization laboratories. Five different fields are addressed: benchmarking experiments for radiation damage modelling, the application of micro-mechanical characterization methods, synchrotron and neutron radiation-based techniques and advanced nanoscopic analysis based on transmission electron microscopy. All these fields need to be exploited further by the fusion materials community for timely materials solutions for a DEMO reactor. In order to integrate these materials research fields, FEMaS acted as a co-organizer for the 2011 workshop and successfully introduced a number of participants from research labs and universities into the PFMC community. Plasma-facing materials experience particularly hostile conditions as they are subjected to extremely high heat loads and very high particle and neutron fluxes. They must have high thermal conductivity for efficient heat transport, high cohesive energy for low erosion by particle bombardment and low atomic number to minimize plasma cooling. These contradictory requirements make the development of plasma-facing materials one of the greatest challenges ever faced by materials scientists. The erosion of plasma-facing materials is one of the main factors influencing the operational schedule of experimental fusion reactors and future power plants. A number of materials selected for current designs cannot withstand the presently foreseen plasma scenarios of a power plant for a commercially viable period of time. Therefore, further coordinated development of plasma scenarios and materials is essential for the realization of fusion as an energy source. The design and development of plasma-facing materials requires a detailed understanding of the processes that occur when a material surface is bombarded with an intense flux of heat, particles and neutrons simultaneously. These materials-related topics are the focus of this series of workshops which has established itself as a discussion forum for experts from research institutions and industry dealing with materials for plasma-facing components in present and future thermonuclear fusion devices. During the joint conference PFMC-13/FEMaS-1 recent developments and research results in the following fields were addressed: carbon, beryllium, and tungsten based materials mixed materials erosion and redeposition high heat flux component development benchmarking of radiation damage modelling synchrotron and neutron based characterization techniques application of advanced transmission electron microscopy and micro-/nano-mechanical testing. With the approaching technical realization of ITER, the ITER-related PFMC topics are naturally the main focus of research. In this respect the start of the ITER-like wall experiment at JET is of paramount importance for our community and several presentations were devoted to this topic. The start of the experimental campaign shortly after PFMC-13/FEMaS-1 will most probably bring about many exciting new results and leaves us eagerly awaiting the next PFMC conference. Several other topics which are of significant relevance for the preparation of ITER were addressed. Among them were dust detection and analysis which is a safety concern and the behaviour of beryllium. Due to the toxicity of beryllium dust, great care has to be taken in the handling of beryllium-containing samples and, as a consequence, only a very limited number of places are available worldwide where such samples can be prepared and investigated. For a solid database and a sound understanding of beryllium and beryllium-containing mixed materials much more effort is necessary in the near future. Naturally, traditional PFMC topics such as first-wall lifetime, testing and characterization of plasma-facing components and hydrogen inventory had their appropriate share of the programme. Not to forget carbon, the nucleating material for this workshop series. Although it will, according to present planning, play only a minor role towards the realization of a DEMO reactor, it is still of importance for current machines and was covered in a large number of poster contributions. Topics receiving continuously increasing attention are those related to devices beyond ITER. Such topics are the development of advanced materials, their behaviour under high heat loads and, in particular, the consequences of neutron damage. The issue which was treated in quite a number of contributions was the simulation of neutron damage by implantation of heavy ions and its influence on hydrogen retention. This is presumably a topic which will receive continuous attention in the years to come. As a consequence of the joint organization with the FEMaS project, several presentations addressed advanced characterization techniques. Remarkable examples of 3D tomography images of plasma-facing components using x-ray- or neutron-based techniques were shown. Such methods allow non-destructive and element-resolved analyses of buried interfaces and are therefore a very promising tool for future investigations of plasma-facing components. It would be desirable that many colleagues of the FEMaS community who attended PFMC-13/FEMaS-1 for the first time would also participate in future events of this series. Thirty five invited lectures and oral contributions and 192 posters were presented by participants coming from research laboratories and industrial companies. Two hundered and eighty two researchers from 27 countries from all over the world participated in the lively and intense exchange of results and new ideas. An additional objective of the series of PFMC workshops was and is to encourage the participation of young talented scientists and to spark their interest in this field. For that reason, the workshop started on its first day with a tutorial session. Experts in their respective fields presented in total eight introductory lectures ranging from the basics of plasma-wall interactions to the engineering of plasma-facing components for ITER. Although originally intended for students and newcomers to the field, these tutorial lectures also enjoy great popularity among senior scientist and are in the meantime an indispensable ingredient and a trademark of this workshop series. The event was organized by the IPP, Garching and received substantial financial support from the European Commission through FEMaS. We are very thankful to the staff of IPP who helped with the organization. Our most cordial thanks and gratitude go to Mrs Christina Stahlberg and Mrs Jutta Koser for their help in the organization and at the front desk. Our most sincere words of appreciation go to our colleague Elmar Neitzert who was in charge of administrative organization. The present proceedings of PFMC-13/FEMaS-1 contain in total 83 peer-reviewed publications covering the contents of most of the oral presentations and of a number of poster contributions which were pre-selected by the programme committee. The papers reflect the development and actual status of the field. We thank all participants for their contributions and we particularly thank the referees for their systematic and diligent reviews of the submitted articles. It is due to their commitment and punctual return of reviews that the proceedings can appear in this relative short time after the meeting. In a meeting of the programme committee during the conferences a few changes in the committee composition were decided. Paul Coad retired and has left the programme committee. We cordially thank Paul Coad for his long-time service as a committee member and wish him the very best for the future. We are very happy that Guy Matthews (CCFE, Culham, UK) accepted the invitation to be his successor. Furthermore, to strengthen the international character of the event, it was decided to invite an additional representative from Japan to the programme committee. Noriyasu Ohno from Nagoya University accepted the invitation. To maintain close contact to the FEMaS community the programme committee further decided to invite Christian Linsmeier from IPP, Garching. Another important decision was taken: in view of the size that the event has reached it was decided to change the name from 'workshop' to 'conference'. So the next event in this series will be the PFMC-14 conference. It will be organized by FZ Jülich and most probably take place in spring 2013.

Low-reactive circulating fluidized bed combustion (CFBC) fly ashes as source material for geopolymer synthesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu Hui; Li Qin; Shen Lifeng

2010-01-15

In this contribution, low-reactive circulating fluidized bed combustion (CFBC) fly ashes (CFAs) have firstly been utilized as a source material for geopolymer synthesis. An alkali fusion process was employed to promote the dissolution of Si and Al species from the CFAs, and thus to enhance the reactivity of the ashes. A high-reactive metakaolin (MK) was also used to consume the excess alkali needed for the fusion. Reactivities of the CFAs and MK were examined by a series of dissolution tests in sodium hydroxide solutions. Geopolymer samples were prepared by alkali activation of the source materials using a sodium silicate solutionmore » as the activator. The synthesized products were characterized by mechanical testing, scanning electron microscopy (SEM), X-ray diffractography (XRD), as well as Fourier transform infrared spectroscopy (FTIR). The results of this study indicate that, via enhancing the reactivity by alkali fusion and balancing the Na/Al ratio by additional aluminosilicate source, low-reactive CFAs could also be recycled as an alternative source material for geopolymer production.« less

Influence of 45S5 Bioactive Glass in A Standard Calcium Phosphate Collagen Bone Graft Substitute on the Posterolateral Fusion of Rabbit Spine.

PubMed

Pugely, Andrew J; Petersen, Emily B; DeVries-Watson, Nicole; Fredericks, Douglas C

2017-01-01

Spinal fusion surgery is an effective but costly treatment for select spinal pathology. Historically iliac crest bone graft (ICBG) has remained the gold standard for achieving successful arthrodesis. Given well-established morbidity autograft harvest, multiple bone graft replacements, void fillers, and extenders have been developed. The objective of this study was to evaluate the in vivo efficacy and safety of two mineralized collagen bone void filler materials similar in composition. Both bone void fillers were composed of hydroxyapatite (HA), tricalcium phosphate (TCP) and bovine collagen. The first test article (Bi-Ostetic bioactive glass foam or "45S5") also contained 45S5 bioactive glass particles while the second test article (Formagraft or "FG") did not. 45S5 and FG were combined with bone marrow aspirate and iliac crest autograft and compared to ICBG in an established posterolateral spine fusion rabbit model. Sixty-nine mature New Zealand White rabbits were divided into 3 test cohorts: ICBG, 45S5, and FG. A Posterolateral fusion model previous validated was utilized to assess fusion efficacy. The test groups were evaluated for spine fusion rate, new bone formation, graft resorption and inflammatory response using radiographic, μCT, biomechanical and histological endpoints at 4, 8 and 12 weeks following implantation. There were 4 clinical complications unrelated to the graft materials and were evenly split between groups (ICBG graft harvest complications; hind limb mobility, chronic pain) and were euthanized. These omissions did not affect the overall outcome of the study. Radiographic scoring of the fusion sites indicated a normal healing response in all test groups, with no adverse reactions and similar progressions of new bone formation observed over time. All groups demonstrated significantly less range of motion in both flexion/extension and lateral bending compared to normal not-fused controls, which supports fusion results observed in the other endpoints. Fusion occurred earlier in the 45S5 group: ICBG 0%, FG 0%, and 45S5 20% at 4 weeks; ICBG 43%, FG 38%, and 45S5 50% at 8 weeks; and ICBG 50%, FG 56%, and 45S5 56% at 12 weeks. Histopathology analysis of the fusion masses, from each test article and time point, indicated an expected normal response for resorbable calcium phosphate (HA/TCP) and collagen graft material. Mild inflammation with macrophage and multinucleated giant cell response to the graft material was evident in all test groups. This study has confirmed the biocompatibility, safety, efficacy and bone healing characteristics of the HA-TCP collagen (with or without 45S5 bioactive glass) composites. The results show that the 3 test groups had equivalent long-term fusion performance and outcome at 12 weeks. However, the presence of 45S5 bioactive glass seemed to accelerate the fusion process as evidenced by the higher fusion rates at 4 and 8 weeks for the HA-TCP-collagen composite containing bioactive glass particles. The results also demonstrate that the HA-TCP-45S5 bioactive glass-collagen composite used as an extender closely mirrors the healing characteristics (i.e. amount and quality of bone) of the 100% autograft group.

A Primer for Education/Outreach to the Classroom and Community

NASA Astrophysics Data System (ADS)

Zaleskiewicz, Ted

2002-11-01

As one example of successful cooperation among major plasma/fusion research laboratories in the United States and Europe, we discuss the development of the well-known classroom teaching chart, "Fusion - Physics of a Fundamental Energy Source", and associated materials produced by the Contemporary Physics Education Project(CPEP). CPEP is a not-for-profit organization of physicists and teachers incorporated to develop teaching materials on contemporary physics topics suitable for use in the introductory (high school and college) classroom. The Fusion Chart is currently available in 7 languages: English, Flemish, French, German, Italian, Portuguese, and Spanish. The series of supporting materials include a Teacher's Guide, 7 hands-on classroom activities, and a Web supplement at http://FusEdWeb.pppl.gov/CPEP/chart.html. All materials are being used successfully in high school teacher training workshops across North America under the auspices of APS/DPP, AAPT, and PTRA (Physics Teaching Resource Agents) programs. Though the materials were developed primarily for use by classroom teachers, they are also valuable resources for individual experts who have the opportunity to make presentations to educational or civic groups. This talk will illustrate various teaching strategies which increase the effectiveness of the materials, including demonstrations of two of the classroom activities, with audience participation invited.

High-heat-flux testing of irradiated tungsten-based materials for fusion applications using infrared plasma arc lamps

DOE PAGES

Sabau, Adrian S.; Ohriner, Evan K.; Kiggans, Jim; ...

2014-11-01

Testing of advanced materials and component mock-ups under prototypical fusion high-heat-flux conditions, while historically a mainstay of fusion research, has proved to be quite challenging, especially for irradiated materials. A new high-heat-flux–testing (HHFT) facility based on water-wall plasma arc lamps (PALs) is now introduced for materials and small-component testing. Two PAL systems, utilizing a 12 000°C plasma arc contained in a quartz tube cooled by a spiral water flow over the inside tube surface, provide maximum incident heat fluxes of 4.2 and 27 MW/m 2 over areas of 9×12 and 1×10 cm 2, respectively. This paper will present the overallmore » design and implementation of a PAL-based irradiated material target station (IMTS). The IMTS is primarily designed for testing the effects of heat flux or thermal cycling on material coupons of interest, such as those for plasma-facing components. Temperature results are shown for thermal cycling under HHFT of tungsten coupon specimens that were neutron irradiated in HFIR. Finally, radiological surveys indicated minimal contamination of the 36×36×18 cm test section, demonstrating the capability of the new facility to handle irradiated specimens at high temperature.« less

Simultaneous measurement of the HT and DT fusion burn histories in inertial fusion implosions

DOE PAGES

Zylstra, Alex B.; Herrmann, Hans W.; Kim, Yong Ho; ...

2017-05-23

Measuring the thermonuclear burn history is an important way to diagnose inertial fusion implosions. Here, using the gas Cherenkov detectors at the OMEGA laser facility, we measure the HT fusion burn in a H 2+T 2 gas-fueled implosion for the first time. Then, using multiple detectors with varied Cherenkov thresholds, we demonstrate a technique for simultaneously measuring both the HT and DT burn histories from an implosion where the total reaction yields are comparable. This new technique will be used to study material mixing and kinetic phenomena in implosions.

Simultaneous measurement of the HT and DT fusion burn histories in inertial fusion implosions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zylstra, Alex B.; Herrmann, Hans W.; Kim, Yong Ho

Measuring the thermonuclear burn history is an important way to diagnose inertial fusion implosions. Here, using the gas Cherenkov detectors at the OMEGA laser facility, we measure the HT fusion burn in a H 2+T 2 gas-fueled implosion for the first time. Then, using multiple detectors with varied Cherenkov thresholds, we demonstrate a technique for simultaneously measuring both the HT and DT burn histories from an implosion where the total reaction yields are comparable. This new technique will be used to study material mixing and kinetic phenomena in implosions.

Ultrasound-ultrasound image overlay fusion improves real-time control of radiofrequency ablation margin in the treatment of hepatocellular carcinoma.

PubMed

Minami, Yasunori; Minami, Tomohiro; Hagiwara, Satoru; Ida, Hiroshi; Ueshima, Kazuomi; Nishida, Naoshi; Murakami, Takamichi; Kudo, Masatoshi

2018-05-01

To assess the clinical feasibility of US-US image overlay fusion with evaluation of the ablative margin in radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). Fifty-three patients with 68 HCCs measuring 0.9-4.0 cm who underwent RFA guided by US-US overlay image fusion were included in this retrospective study. By an overlay of pre-/postoperative US, the tumor image could be projected onto the ablative hyperechoic zone. Therefore, the ablative margin three-dimensionally could be shown during the RFA procedure. US-US image overlay was compared to dynamic CT a few days after RFA for assessment of early treatment response. Accuracy of graded response was calculated, and the performance of US-US image overlay fusion was compared with that of CT using a Kappa agreement test. Technically effective ablation was achieved in a single session, and 59 HCCs (86.8 %) succeeded in obtaining a 5-mm margin on CT. The response with US-US image overlay correctly predicted early CT evaluation with an accuracy of 92.6 % (63/68) (k = 0.67; 95 % CI: 0.39-0.95). US-US image overlay fusion can be proposed as a feasible guidance in RFA with a safety margin and predicts early response of treatment assessment with high accuracy. • US-US image overlay fusion visualizes the ablative margin during RFA procedure. • Visualizing the margin during the procedure can prompt immediate complementary treatment. • US image fusion correlates with the results of early evaluation CT.

Message from the Editor

NASA Astrophysics Data System (ADS)

Stambaugh, Ronald D.

2014-01-01

This last year being an odd numbered year, the pages of Nuclear Fusion saw a large influx of expanded papers from the 2012 Fusion Energy Conference in San Diego. Many papers have focused on the scientific and technical challenges posed by ITER. Contributions are steadily increasing from the new superconducting tokamaks in Asia. The ITER Project continues to move ahead. Construction at the Cadarache site is quite remarkable. Buildings completed include the huge Poloidal Field Coils Winding Facility and the Headquarters building, which has been occupied by the ITER staff. Work is progressing on the Assembly building and the Cryostat Workshop. The base of the tokamak complex is being laid. Besides the construction that is taking place and will take place at the site, components from around the world have to navigate the complex route from Marseilles to the site. A test convoy replicating the dimensions and weights of the most exceptional ITER loads successfully traversed that route in 2013. We are pleased to report that the IAEA and ITER have finalized the agreement for ITER authors to publish papers in Nuclear Fusion . Nuclear Fusion is proud to continue its key role in providing the leading forum for the documentation of scientific progress and exchange of research results internationally toward fusion energy. Refereeing The Nuclear Fusion editorial office appreciates greatly the effort made by our referees to sustain the high quality of the journal. Since January 2005, we have been offering the most active referees over the past year a personal subscription to Nuclear Fusion with electronic access for one year, free of charge. We have excluded our Board Members, Guest Editors of special editions and those referees who were already listed in previous years. The following people have been selected: J.M. Canik, Oak Ridge National Laboratory, USA I.T. Chapman, Culham Centre for Fusion Energy, UK L.-G. Eriksson, Commission of the European Communities, Belgium T. Evans, General Atomics, USA A. Hassanein, Purdue University, USA Y.-M. Jeon, National Fusion Research Institute, Spain S. Kajita, Nagoya University, Japan T.P. Kiviniemi, Aalto University, Finland R.M. More, Lawrence Livermore National Laboratory, USA F. Sattin, Associazione Euratom-ENEA-CNR, Italy J.A. Snipes, ITER Organization, France W. Suttrop, Max Planck Institute for Plasma Physics-Garching, Germany F.L. Tabares, Energy Environment and Technology Research Centre, Spain Y. Ueda, Osaka University, Japan V.S. Voitsenya, Kharkov Institute of Physics and Technology, Ukraine G. Xu, Chinese Academy of Sciences-Hefei Institutes of Physical Sciences, People's Republic of China In addition, there is a group of several hundred referees who have helped us in the past year to maintain the high scientific standard of Nuclear Fusion . At the end of this issue we give the full list of all referees for 2013. Our thanks to them! We also wish to express our thanks to Paul Thomas, who served as Guest Editor for the special issue of the overview and summary reports from the 24th Fusion Energy Conference in San Diego, October 2012. This issue is of great value as a summary of the major developments worldwide in fusion research in the last two years. Authors The winner of the 2013 Nuclear Fusion Award is D.G. Whyte for the paper: I-mode: an H-mode energy confinement regime with L-mode particle transport in Alcator C-Mod [1], and we congratulate him and coauthors on this achievement. We also note special topic papers published in 2013: Technical challenges in the construction of the steady-state stellarator Wendestein 7-X by H.S. Bosch et al [2], Power requirements for electron cyclotron current drive and ion cyclotron resonance heating for sawtooth control in ITER by I.T. Chapman et al [3] and IFMIF: overview of the validation activities by J. Knaster et al [4]. The Board of Editors The Board of Editors has had a substantial turnover in members. For their great service to the journal, we wish to thank the following outgoing Board Members whose term of service was reached at the end of 2012: Keith Burrell, Atsushi Fukuyama, Guenter Janeschitz, Myeun Kwon, Alberto Loarte, Derek Stork, Tony Taylor and Kazuo Toi. We welcome the new Board Members who have joined the Board from the start of 2013: Pietro Barabaschi, Riccardo Betti, Rich Callis, Wonho Choi, Yasuaki Kishimoto, Joaquin Sánchez, Paul Thomas, Mickey Wade, Howard Wilson, Hiroshi Yamada and Steve Zinkle. We look forward to working with the Board to maintain the high standing of Nuclear Fusion . The Nuclear Fusion office and IOP Publishing Just as the journal depends on the authors, referees, and Board of Editors, so its success is also due to the tireless and largely unsung efforts of the IAEA Nuclear Fusion office in Vienna and IOP Publishing in Bristol. I would like to express my personal thanks to the team for the support that they have given to me, the authors and the referees. Season's greetings I would like to wish our readers, authors, referees, Board of Editors, and Vienna and Bristol office staff season's greetings and thank them for their contributions to Nuclear Fusion in 2013. References [1] Whyte D.G. et al 2010 I-mode: an H-mode energy confinement regime with L-mode particle transport in Alcator C-Mod Nucl. Fusion 50 105005 [2] Bosch H.-S. et al 2013 Technical challenges in the construction of the steady-state stellarator Wendelstein 7-X Nucl. Fusion 53 126001 [3] Chapman I.T. et al 2013 Power requirements for electron cyclotron current drive and ion cyclotron resonance heating for sawtooth control in ITER Nucl. Fusion 53 066001 [4] Knaster J. et al 2013 IFMIF: overview of the validation activities Nucl. Fusion 53 116001

Current Status and Recent Research Achievements in SiC/SiC Composites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katoh, Yutai; Snead, Lance L.; Henager, Charles H.

2014-12-01

The development and maturation of the silicon carbide fiber-reinforced silicon carbide matrix (SiC/SiC) composite system for fusion applications has seen the evolution from fundamental development and understanding of the material system and its behavior in a hostile irradiation environment to the current effort which essentially is a broad-based program of technology, directed at moving this material class from a laboratory curiosity to an engineering material. This paper lays out the recent international scientific and technological achievements in the development of SiC/SiC composite material technologies for fusion application and will discuss future research directions. It also reviews the materials system inmore » the larger context of progress to maturity as an engineering material for both the larger nuclear community and for general engineering applications.« less

Spatial heterogeneity of tungsten transmutation in a fusion device

NASA Astrophysics Data System (ADS)

Gilbert, M. R.; Sublet, J.-Ch.; Dudarev, S. L.

2017-04-01

Accurately quantifying the transmutation rate of tungsten (W) under neutron irradiation is a necessary requirement in the assessment of its performance as an armour material in a fusion power plant. The usual approach of calculating average responses, assuming large, homogenised material volumes, is insufficient to capture the full complexity of the transmutation picture in the context of a realistic fusion power plant design, particularly for rhenium (Re) production from W. Combined neutron transport and inventory simulations for representative spatially heterogeneous high-resolution models of a fusion power plant show that the production rate of Re is strongly influenced by the surrounding local spatial environment. Localised variation in neutron moderation (slowing down) due to structural steel and coolant, particularly water, can dramatically increase Re production because of the huge cross sections of giant resolved resonances in the neutron-capture reaction of 186W at low neutron energies. Calculations using cross section data corrected for temperature (Doppler) effects suggest that temperature may have a relatively lesser influence on transmutation rates.

Phase-Change Heat-Storage Module

NASA Technical Reports Server (NTRS)

Mulligan, James C.

1989-01-01

Heat-storage module accommodates momentary heating or cooling overload in pumped-liquid heat-transfer system. Large heat-storage capacity of module provided by heat of fusion of material that freezes at or near temperature desired to maintain object to be heated or cooled. Module involves relatively small penalties in weight, cost, and size and more than compensates by enabling design of rest of system to handle only average load. Latent heat of fusion of phase-change material provides large heat-storage capacity in small volume.

Fusion Sciences Education Outreach in the Middle Schools, an Unplanned Case Study

NASA Astrophysics Data System (ADS)

Danielson, C. A.

1997-11-01

Before bringing a class to General Atomics (GA) for the DIII--D educational tour, the teacher is provided with pre-tour materials which include a videotape, curriculum notebook and fusion poster. These materials are used in the classroom to familiarize students with fusion concepts before the tour. This presentation will focus on the results of projects of 7th grade students of Chula Vista Junior High School (a magnet school for performing arts with a majority of Hispanic students). The assignment given by Physics Teacher Caryn Hoffman to her students prior to the tour was to focus on one or two of the DIII--D tour guides, ask questions relating to their careers in science and then prepare a presentation based on their interviews and their tour experience. The completed projects were very diverse -- calendars, comic strips, newspapers, plays, and board games were some of the media the students used. Tour guides selected by the students ranged from physicists, designers and computer support personnel. Project results reflected a surprisingly good understanding of fusion science concepts. Subsequent classroom interviews with the students demonstrated an overall increase in science interest and a specific interest in plasma and fusion research.

Nuclear Fusion Blast and Electrode Lifetimes in a PJMIF Reactor

NASA Astrophysics Data System (ADS)

Thio, Y. C. Francis; Witherspoon, F. D.; Case, A.; Brockington, S.; Cruz, E.; Luna, M.; Hsu, S. C.

2017-10-01

We present an analysis and numerical simulation of the nuclear blast from the micro-explosion following the completion of the fusion burn for a baseline design of a PJMIF fusion reactor with a fusion gain of 20. The stagnation pressure from the blast against the chamber wall defines the engineering requirement for the structural design of the first wall and the plasma guns. We also present an analysis of the lifetimes of the electrodes of the plasma guns which are exposed to (1) the high current, and (2) the neutron produced by the fusion reactions. We anticipate that the gun electrodes are made of tungsten alloys as plasma facing components reinforced structurally by appropriate steel alloys. Making reasonable assumptions about the electrode erosion rate (100 ng/C transfer), the electrode lifetime limited by the erosion rate is estimated to be between 19 and 24 million pulses before replacement. Based on known neutron radiation effects on structural materials such as steel alloys and plasma facing component materials such as tungsten alloys, the plasma guns are expected to survive some 22 million shots. At 1 Hz, this equal to about 6 months of continuous operation before they need to be replaced. Work supported by Strong Atomics, LLC.

Lipid tail protrusions initiate spontaneous insertion of charged, amphiphilic nanoparticles into lipid bilayers

NASA Astrophysics Data System (ADS)

van Lehn, Reid; Ricci, Maria; Carney, Randy; Voitchovsky, Kislon; Stellacci, Francesco; Alexander-Katz, Alfredo

2014-03-01

Vesicle fusion is a primary mechanism used to mediate the uptake and trafficking of materials both into and between cells. The pathway of vesicle fusion involves the formation of a lipid stalk in which the hydrophobic core regions of two closely associated bilayers merge. The transition state for stalk formation requires the transient protrusion of hydrophobic lipid tails into solvent; favorable contact between these hydrophobic tails then drives stalk creation. In this work, we use unbiased atomistic molecular dynamics simulations to show that lipid tail protrusions can also induce the insertion of charged, amphiphilic nanoparticles (NPs) into lipid bilayers. As in the case of vesicle fusion, the rate-limiting step for NP-bilayer fusion is the stochastic protrusion of aliphatic lipid tails into solvent and into contact with hydrophobic material in the amphiphilic NP monolayer. We confirm our predictions with experiments on supported lipid bilayers. The strong agreement between simulation and experiments indicates that the pre-stalk transition associated with vesicle fusion may be a general mechanism for the insertion of amphiphilic nano-objects that could be prominent in biological systems given the widespread use of NPs in applications ranging from drug delivery to biosensing.

76 FR 43743 - Pipeline Safety: Meetings of the Technical Pipeline Safety Standards Committee and the Technical...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-21

... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration [Docket No. PHMSA-2011-0127] Pipeline Safety: Meetings of the Technical Pipeline Safety Standards Committee and the Technical Hazardous Liquid Pipeline Safety Standards Committee AGENCY: Pipeline and Hazardous Materials...

Fast degradable citrate-based bone scaffold promotes spinal fusion.

PubMed

Tang, Jiajun; Guo, Jinshan; Li, Zhen; Yang, Cheng; Xie, Denghui; Chen, Jian; Li, Shengfa; Li, Shaolin; Kim, Gloria B; Bai, Xiaochun; Zhang, Zhongmin; Yang, Jian

2015-07-21

It is well known that high rates of fusion failure and pseudoarthrosis development (5~35%) are concomitant in spinal fusion surgery, which was ascribed to the shortage of suitable materials for bone regeneration. Citrate was recently recognized to play an indispensable role in enhancing osteconductivity and osteoinductivity, and promoting bone formation. To address the material challenges in spinal fusion surgery, we have synthesized mechanically robust and fast degrading citrate-based polymers by incorporating N-methyldiethanolamine (MDEA) into clickable poly(1, 8-octanediol citrates) (POC-click), referred to as POC-M-click. The obtained POC-M-click were fabricated into POC-M-click-HA matchstick scaffolds by compositing with hydroxyapatite (HA) for interbody spinal fusion in a rabbit model. Spinal fusion was analyzed by radiography, manual palpation, biomechanical testing, and histological evaluation. At 4 and 8 weeks post surgery, POC-M-click-HA scaffolds presented optimal degradation rates that facilitated faster new bone formation and higher spinal fusion rates (11.2±3.7, 80±4.5 at week 4 and 8, respectively) than the poly(L-lactic acid)-HA (PLLA-HA) control group (9.3±2.4 and 71.1±4.4) (p<0.05). The POC-M-click-HA scaffold-fused vertebrates possessed a maximum load and stiffness of 880.8±14.5 N and 843.2±22.4 N/mm, respectively, which were also much higher than those of the PLLA-HA group (maximum: 712.0±37.5 N, stiffness: 622.5±28.4 N/mm, p<0.05). Overall, the results suggest that POC-M-click-HA scaffolds could potentially serve as promising bone grafts for spinal fusion applications.

Fast degradable citrate-based bone scaffold promotes spinal fusion

PubMed Central

Tang, Jiajun; Guo, Jinshan; Li, Zhen; Yang, Cheng; Xie, Denghui; Chen, Jian; Li, Shengfa; Li, Shaolin; Kim, Gloria B.; Bai, Xiaochun; Zhang, Zhongmin; Yang, Jian

2015-01-01

It is well known that high rates of fusion failure and pseudoarthrosis development (5~35%) are concomitant in spinal fusion surgery, which was ascribed to the shortage of suitable materials for bone regeneration. Citrate was recently recognized to play an indispensable role in enhancing osteconductivity and osteoinductivity, and promoting bone formation. To address the material challenges in spinal fusion surgery, we have synthesized mechanically robust and fast degrading citrate-based polymers by incorporating N-methyldiethanolamine (MDEA) into clickable poly(1, 8-octanediol citrates) (POC-click), referred to as POC-M-click. The obtained POC-M-click were fabricated into POC-M-click-HA matchstick scaffolds by compositing with hydroxyapatite (HA) for interbody spinal fusion in a rabbit model. Spinal fusion was analyzed by radiography, manual palpation, biomechanical testing, and histological evaluation. At 4 and 8 weeks post surgery, POC-M-click-HA scaffolds presented optimal degradation rates that facilitated faster new bone formation and higher spinal fusion rates (11.2±3.7, 80±4.5 at week 4 and 8, respectively) than the poly(L-lactic acid)-HA (PLLA-HA) control group (9.3±2.4 and 71.1±4.4) (p<0.05). The POC-M-click-HA scaffold-fused vertebrates possessed a maximum load and stiffness of 880.8±14.5 N and 843.2±22.4 N/mm, respectively, which were also much higher than those of the PLLA-HA group (maximum: 712.0±37.5 N, stiffness: 622.5±28.4 N/mm, p<0.05). Overall, the results suggest that POC-M-click-HA scaffolds could potentially serve as promising bone grafts for spinal fusion applications. PMID:26213625

Research on precise modeling of buildings based on multi-source data fusion of air to ground

NASA Astrophysics Data System (ADS)

Li, Yongqiang; Niu, Lubiao; Yang, Shasha; Li, Lixue; Zhang, Xitong

2016-03-01

Aims at the accuracy problem of precise modeling of buildings, a test research was conducted based on multi-source data for buildings of the same test area , including top data of air-borne LiDAR, aerial orthophotos, and façade data of vehicle-borne LiDAR. After accurately extracted the top and bottom outlines of building clusters, a series of qualitative and quantitative analysis was carried out for the 2D interval between outlines. Research results provide a reliable accuracy support for precise modeling of buildings of air ground multi-source data fusion, on the same time, discussed some solution for key technical problems.

The Physics Basis of ITER Confinement

NASA Astrophysics Data System (ADS)

Wagner, F.

2009-02-01

ITER will be the first fusion reactor and the 50 year old dream of fusion scientists will become reality. The quality of magnetic confinement will decide about the success of ITER, directly in the form of the confinement time and indirectly because it decides about the plasma parameters and the fluxes, which cross the separatrix and have to be handled externally by technical means. This lecture portrays some of the basic principles which govern plasma confinement, uses dimensionless scaling to set the limits for the predictions for ITER, an approach which also shows the limitations of the predictions, and describes briefly the major characteristics and physics behind the H-mode—the preferred confinement regime of ITER.

FOREWORD: 12th International Workshop on Plasma-Facing Materials and Components for Fusion Applications 12th International Workshop on Plasma-Facing Materials and Components for Fusion Applications

NASA Astrophysics Data System (ADS)

Kreter, Arkadi; Linke, Jochen; Rubel, Marek

2009-12-01

The 12th International Workshop on Plasma-Facing Materials and Components for Fusion Applications (PFMC-12) was held in Forschungszentrum Jülich (FZJ) in Germany in May 2009. This symposium is the successor to the International Workshop on Carbon Materials for Fusion Applications series. Between 1985 and 2003, 10 'Carbon Workshops' were organized in Jülich, Stockholm and Hohenkammer. After this time, the scope of the symposium was redefined to reflect the new requirements of ITER and the ongoing evolution of the field. The workshop was first organized under its new name in 2006 in Greifswald, Germany. The main objective of this conference series is to provide a discussion forum for experts from research institutions and industry dealing with materials for plasma-facing components in present and future controlled fusion devices. The operation of ASDEX-Upgrade with tungsten-coated wall, the fast progress of the ITER-Like Wall Project at JET, the plans for the EAST tokamak to install tungsten, the start of ITER construction and a discussion about the wall material for DEMO all emphasize the importance of plasma-wall interactions and component behaviour, and give much momentum to the field. In this context, the properties and behaviour of beryllium, carbon and tungsten under plasma impact are research topics of foremost relevance and importance. Our community realizes both the enormous advantages and serious drawbacks of all the candidate materials. As a result, discussion is in progress as to whether to use carbon in ITER during the initial phase of operation or to abandon this element and use only metal components from the start. There is broad knowledge about carbon, both in terms of its excellent power-handling capabilities and the drawbacks related to chemical reactivity with fuel species and, as a consequence, about problems arising from fuel inventory and dust formation. We are learning continuously about beryllium and tungsten under fusion conditions, but our knowledge is still limited, especially in relation to the behaviour of these metals in environments containing multiple species. There are many appealing issues related to material mixing and fuel retention that call for robust and comprehensive studies. In this sense, the aim of the workshop is not only to discuss hot topics, but also to identify the most important research areas and those that need urgent solutions. Another topic of foremost relevance to ITER is the development of plasma-facing components that are able to withstand extreme power fluxes, in particular, those during transient phases. Materials and production methods for high-heat-flux components have to be further developed and industrialized. A key requirement in this field is the development of non-destructive testing methods for the qualification of methods and quality assessment during production. Invited talks and contributed presentations therefore dealt with aspects of fundamental processes, experimental findings, advanced modelling and the technology of fusion reactor components. Several areas were selected as the major topics of PFMC-12: materials for the ITER-divertor (erosion, redeposition, fuel retention) carbon-based materials tungsten and tungsten coatings beryllium mixed materials (intentional and non-intentional) the ITER-Like Wall Project materials under high-heat-flux loads including transients (ELMs, disruptions) technology and testing of plasma-facing components neutron effects in plasma-facing materials. 26 invited lectures and oral contributions, and 131 posters were presented by participants from research laboratories and industrial companies. 210 researchers from 24 countries from all over the world participated in a lively and intense exchange of knowledge and ideas. The workshop was hosted by Forschungszentrum Jülich (FZJ), a centre where the integration of science and technology for fusion reactor materials has been a focus for decades. This is reflected by the operation of several devices vital for progress in fusion research. TEXTOR (Toroidal EXperiment for Technology Oriented Research) is a mission-oriented tokamak for the study of plasma-wall interactions and testing of materials in fusion environments. JUDITH-1 (JÜlich DIvertor Test facility in Hot-cell) and the recently started JUDITH-2 are the most powerful test beds for studies of material performance under steady-state or pulsed power loads. The results of testing in JUDITH establish the background for material qualification. The expertize of FZJ in fusion engineering is vital for the construction of the Wendelstein-7X stellarator in Greifswald and the diagnostics for the ITER plasma. Finally, there is a group of eminent theoreticians and modellers at work in FZJ. As a consequence, FZJ is the home of the supercomputer, High Performance Computing-For Fusion (HPC-FF). During the workshop, special guided laboratory tours were organized to get the participants acquainted with the experimental facilities at FZJ: TEXTOR, JUDITH and HPC-FF. The quality of the talks, posters and discussions, and the comfortable conference facilities were of great importance but activities outside fusion science also formed part of the workshop. A guided tour in the Old Town of Aachen was very much appreciated by all participants; a stroll in this beautiful place was not only a relaxing moment but also put participants in touch with a great deal of European history. Big and long-term projects always attract young, ambitious people. The recruitment of talented scientists is a conditio sine qua non for the future success and progress of fusion science and engineering. The enthusiasm of students is very important but not sufficient; it is the responsibility of older colleagues to get students acquainted with the major issues and challenges. For this reason, the workshop was preceded by a series of tutorials on plasma-wall interactions and properties, and testing of relevant materials. The lectures were met with a great response: not only did over thirty young colleagues register but also senior scientists registered for the course and were very active in discussions. The workshop was supported financially by Forschungszentrum Jülich and the ExtreMat Integrated Project, a programme for the development and study of new materials for extreme environments. We are very grateful to the staff of Forschungszentrum who helped with the organization. Our most cordial thanks and gratitude go to Yasmin Fattah, Angelika Hallmanns, Gabriele Knauf and Gerd Boeling for all their kindness and efficiency, which helped all of us to enjoy the meeting. We thank most sincerely our colleagues Gerald Pintsuk, Takeshi Hirai and Andrey Litnovsky for their most professional work in the construction and operation of the conference webpage, the preparation of the sessions and for all other elements that were vital for the smooth running of the meeting. We thank very much Marliese Felden and Ralf-Uwe Limbach who very kindly and professionally took care of the photographic documentation of the workshop. The proceedings of this workshop contains 67 peer-reviewed articles covering the contents of most of the invited presentations and a number of poster contributions which were pre-selected by the programme committee. The papers reflect the development and actual status of the field. We thank all participants for their contributions and the referees for their smooth and efficient peer-review. Thank you all for your hard work and co-operation. We are looking forward to seeing you at the next meeting; we invite you to come, though we are not yet able to say 'when' and 'where' we will meet next time. It is a special feature of this conference series that a new meeting is announced only when the community feels that there is substantial new material to be presented and discussed.

Final Technical Report: Collaborative Research Center for Nonlinear Simulation of Energetic Particles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berk, Herbert L.

2018-02-15

The study of this project focused on developing a reduced nonlinear model to describe chirping processes in a fusion plasma. A successful method was developed with results clear enough to allow an analytic theory to be developed that replicates the long term response of a nonlinear phase space structure immersed in the MHD continnuum.

9 CFR 351.11 - Identification and separation of technical animal fats for certification and materials for use...

Code of Federal Regulations, 2012 CFR

2012-01-01

... technical animal fats for certification and materials for use therein; removal of wrappers, etc.; cleaning... AND VOLUNTARY INSPECTION AND CERTIFICATION CERTIFICATION OF TECHNICAL ANIMAL FATS FOR EXPORT Facilities and Operations § 351.11 Identification and separation of technical animal fats for certification...

9 CFR 351.11 - Identification and separation of technical animal fats for certification and materials for use...

Code of Federal Regulations, 2010 CFR

2010-01-01

... technical animal fats for certification and materials for use therein; removal of wrappers, etc.; cleaning... AND VOLUNTARY INSPECTION AND CERTIFICATION CERTIFICATION OF TECHNICAL ANIMAL FATS FOR EXPORT Facilities and Operations § 351.11 Identification and separation of technical animal fats for certification...

9 CFR 351.11 - Identification and separation of technical animal fats for certification and materials for use...

Code of Federal Regulations, 2013 CFR

2013-01-01

... technical animal fats for certification and materials for use therein; removal of wrappers, etc.; cleaning... AND VOLUNTARY INSPECTION AND CERTIFICATION CERTIFICATION OF TECHNICAL ANIMAL FATS FOR EXPORT Facilities and Operations § 351.11 Identification and separation of technical animal fats for certification...

9 CFR 351.11 - Identification and separation of technical animal fats for certification and materials for use...

Code of Federal Regulations, 2014 CFR

2014-01-01

... technical animal fats for certification and materials for use therein; removal of wrappers, etc.; cleaning... AND VOLUNTARY INSPECTION AND CERTIFICATION CERTIFICATION OF TECHNICAL ANIMAL FATS FOR EXPORT Facilities and Operations § 351.11 Identification and separation of technical animal fats for certification...

9 CFR 351.11 - Identification and separation of technical animal fats for certification and materials for use...

Code of Federal Regulations, 2011 CFR

2011-01-01

... technical animal fats for certification and materials for use therein; removal of wrappers, etc.; cleaning... AND VOLUNTARY INSPECTION AND CERTIFICATION CERTIFICATION OF TECHNICAL ANIMAL FATS FOR EXPORT Facilities and Operations § 351.11 Identification and separation of technical animal fats for certification...

Application of imaging fusion combining contrast-enhanced ultrasound and magnetic resonance imaging in detection of hepatic cellular carcinomas undetectable by conventional ultrasound.

PubMed

Dong, Yi; Wang, Wen-Ping; Mao, Feng; Ji, Zheng-Biao; Huang, Bei-Jian

2016-04-01

The aim of this study is to explore the value of volume navigation image fusion-assisted contrast-enhanced ultrasound (CEUS) in detection for radiofrequency ablation guidance of hepatocellular carcinomas (HCCs), which were undetectable on conventional ultrasound. From May 2012 to May 2014, 41 patients with 49 HCCs were included in this study. All lesions were detected by dynamic magnetic resonance imaging (MRI) and planned for radiofrequency ablation but were undetectable on conventional ultrasound. After a bolus injection of 2.4 ml SonoVue® (Bracco, Italy), LOGIQ E9 ultrasound system with volume navigation system (version R1.0.5, GE Healthcare, Milwaukee, WI, USA) was used to fuse CEUS and MRI images. The fusion time, fusion success rate, lesion enhancement pattern, and detection rate were analyzed. Image fusions were conducted successfully in 49 HCCs, the technical success rate was 100%. The average fusion time was (9.2 ± 2.1) min (6-12 min). The mean diameter of HCCs was 25.2 ± 5.3 mm (mean ± SD), and mean depth was 41.8 ± 17.2 mm. The detection rate of HCCs using CEUS/MRI imaging fusion (95.9%, 47/49) was significantly higher than CEUS (42.9%, 21/49) (P < 0.05). For small HCCs (diameter, 1-2 cm), the detection rate using imaging fusion (96.9%, 32/33) was also significantly higher than CEUS (18.2%, 6/33) (P < 0.01). All HCCs displayed a rapid wash-in pattern in the arterial phase of CEUS. Imaging fusion combining CEUS and MRI is a promising technique to improve the detection, precise localization, and accurate diagnosis of undetectable HCCs on conventional ultrasound, especially small and atypical HCCs. © 2015 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

EDITORIAL: Special issue containing papers presented at the 11th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems Special issue containing papers presented at the 11th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems

NASA Astrophysics Data System (ADS)

Kolesnichenko, Ya.

2010-08-01

The history of fusion research resembles the way in which one builds skyscrapers: laying the first foundation stone, one thinks about the top of the skyscraper. At the early stages of fusion, when it became clear that the thermonuclear reactor would operate with DT plasma confined by the magnetic field, the study of the `top item'—the physics of 3.5 MeV alpha particles produced by the DT fusion reaction—was initiated. The first publications on this topic appeared as long ago as the 1960s. At that time, because the physics of alpha particles was far from the experimental demand, investigations were carried out by small groups of theoreticians who hoped to discover important and interesting phenomena in this new research area. Soon after the beginning of the work, theoreticians discovered that alpha particles could excite various instabilities in fusion plasmas. In particular, at the end of the 1960s an Alfvén instability driven by alpha particles was predicted. Later it turned out that a variety of Alfvén instabilities with very different features does exist. Instabilities with perturbations of the Alfvénic type play an important role in current experiments; it is likely that they will affect plasma performance in ITER and future reactors. The first experimental manifestation of instabilities excited by superthermal particles in fusion devices was observed in the PDX tokamak in 1983. In this device a large-scale instability—the so called `fishbone instability'—associated with ions produced by the neutral beam injection resulted in a loss of a large fraction of the injected energy. Since then, the study of energetic-ion-driven instabilities and the effects produced by energetic ions in fusion plasmas has attracted the growing attention of both experimentalists and theorists. Recognizing the importance of this topic, the first conference on fusion alpha particles was held in 1989 in Kyiv under the auspices of the IAEA. The meeting in Kyiv and several subsequent meetings (Aspenäs (1991), Trieste (1993), Princeton (1995), and JET/Abingdon (1997)) were entitled `Alpha Particles in Fusion Research'. During the JET/Abingdon meeting in 1997 it was decided to extend the topic by including other suprathermal particles, in particular accelerated electrons, and rename the meetings accordingly. The subsequent meetings with the current name `Energetic Particles in Magnetic Confinement Systems' were held in Naka (1999), Gothenburg (2001), San Diego (2003), Takayama (2005) and Kloster Seeon (2007). The most recent meeting in this series was held in Kyiv, Ukraine, in September 2009. This was an anniversary meeting, 20 years after the first meeting. Like the first meeting, it was hosted by the Institute for Nuclear Research, National Academy of Sciences of Ukraine. It was attended by about 80 researchers from 18 countries, ITER, and EC. The program of the meeting consisted of 78 presentations, including 12 invited talks, 16 oral contributed talks, and 50 posters, which were selected by the International Advisory Committee (IAC). The IAC consisted of 11 people representing EC (L.-G. Eriksson), Germany (S. Günter), Italy (F. Zonca), Japan (K. Shinohara and K. Toi), Switzerland (A. Fasoli), UK (S. Sharapov), Ukraine (Ya. Kolesnichenko—IAC Chair), USA (H. Berk, W. Heidbrink, and R. Nazikian). The meeting program covered a wide range of physics issues concerning energetic ions in toroidal fusion facilities—tokamaks, stellarators, and spherical tori. Many new interesting and practically important results of both experimental and theoretical studies were reported. The research presented covered topics such as instabilities driven by energetic ions, transport of energetic ions caused by plasma microturbulence and destabilized eigenmodes, non-linear phenomena induced by the instabilities, classical transport processes, effects of runaway electrons, diagnostics of energetic ions and plasmas, and aspects of ITER physics. In addition to these topics, which were also covered at previous conferences in this series and have become conventional, experimental and theoretical results on the influence of energetic ions on bulk plasma transport properties were also reported. Some materials from the meeting are available on the web page http://www.kinr.kiev.ua/TCM/index.html. 24 of the works presented at the meeting are published in this special issue. These works were reviewed to the usual high standard of Nuclear Fusion. The guest editor of this special issue is grateful to the publishers for their cooperation.

Preliminary Comparison of Radioactive Waste Disposal Cost for Fusion and Fission Reactors

NASA Astrophysics Data System (ADS)

Seki, Yasushi; Aoki, Isao; Yamano, Naoki; Tabara, Takashi

1997-09-01

The environmental and economic impact of radioactive waste (radwaste) generated from fusion power reactors using five types of structural materials and a fission reactor has been evaluated and compared. Possible radwaste disposal scenario of fusion radwaste in Japan is considered. The exposure doses were evaluated for the skyshine of gamma-ray during the disposal operation, groundwater migration scenario during the institutional control period of 300 years and future site use scenario after the institutional period. The radwaste generated from a typical light water fission reactor was evaluated using the same methodology as for the fusion reactors. It is found that radwaste from the fusion reactors using F82H and SiC/SiC composites without impurities could be disposed by the shallow land disposal presently applied to the low level waste in Japan. The disposal cost of radwaste from five fusion power reactors and a typical light water reactor were roughly evaluated and compared.

System integration and DICOM image creation for PET-MR fusion.

PubMed

Hsiao, Chia-Hung; Kao, Tsair; Fang, Yu-Hua; Wang, Jiunn-Kuen; Guo, Wan-Yuo; Chao, Liang-Hsiao; Yen, Sang-Hue

2005-03-01

This article demonstrates a gateway system for converting image fusion results to digital imaging and communication in medicine (DICOM) objects. For the purpose of standardization and integration, we have followed the guidelines of the Integrated Healthcare Enterprise technical framework and developed a DICOM gateway. The gateway system combines data from hospital information system, image fusion results, and the information generated itself to constitute new DICOM objects. All the mandatory tags defined in standard DICOM object were generated in the gateway system. The gateway system will generate two series of SOP instances of each PET-MR fusion result; SOP (Service Object Pair) one for the reconstructed magnetic resonance (MR) images and the other for position emission tomography (PET) images. The size, resolution, spatial coordinates, and number of frames are the same in both series of SOP instances. Every new generated MR image exactly fits with one of the reconstructed PET images. Those DICOM images are stored to the picture archiving and communication system (PACS) server by means of standard DICOM protocols. When those images are retrieved and viewed by standard DICOM viewing systems, both images can be viewed at the same anatomy location. This system is useful for precise diagnosis and therapy.

Effects of in situ dual ion beam (He+ and D+) irradiation with simultaneous pulsed heat loading on surface morphology evolution of tungsten-tantalum alloys

NASA Astrophysics Data System (ADS)

Gonderman, S.; Tripathi, J. K.; Sinclair, G.; Novakowski, T. J.; Sizyuk, T.; Hassanein, A.

2018-02-01

The strong thermal and mechanical properties of tungsten (W) are well suited for the harsh fusion environment. However, increasing interest in using tungsten as plasma-facing components (PFCs) has revealed several key issues. These potential roadblocks necessitate more investigation of W and other alternative W based materials exposed to realistic fusion conditions. In this work, W and tungsten-tantalum (W-Ta) alloys were exposed to single (He+) and dual (He+  +  D+) ion irradiations with simultaneous pulsed heat loading to elucidate PFCs response under more realistic conditions. Laser only exposer revealed significantly more damage in W-Ta samples as compared to pure W samples. This was due to the difference in the mechanical properties of the two different materials. Further erosion studies were conducted to evaluate the material degradation due to transient heat loading in both the presence and absence of He+ and/or D+ ions. We concluded that erosion of PFC materials was significantly enhanced due to the presence of ion irradiation. This is important as it demonstrates that there are key synergistic effects resulting from more realistic fusion loading conditions that need to be considered when evaluating the response of plasma facing materials.

Non-critical phase-matching fourth harmonic generation of a 1053-nm laser in an ADP crystal

PubMed Central

Ji, Shaohua; Wang, Fang; Zhu, Lili; Xu, Xinguang; Wang, Zhengping; Sun, Xun

2013-01-01

In current inertial confinement fusion (ICF) facilities, KDP and DKDP crystals are the second harmonic generation (SHG) and third harmonic generation (THG) materials for the Nd:glass laser (1053 nm). Based on the trend for the development of short wavelengths for ICF driving lasers, technical solutions for fourth harmonic generation (FHG) will undoubtedly attract more and more attention. In this paper, the rapid growth of an ADP crystal and non-critical phase-matching (NCPM) FHG of a 1053-nm laser using an ADP crystal are reported. The NCPM temperature is 33.7°C. The conversion efficiency from 526 to 263 nm is 70%, and the angular acceptance range is 55.4 mrad; these results are superior to those for the DKDP crystals. This research has shown that ADP crystals will be a competitive candidate in future ICF facilities when the utilisation of high-energy, high-efficiency UV lasers at wavelengths shorter than the present 351 nm is of interest. PMID:23549389

Non-critical phase-matching fourth harmonic generation of a 1053-nm laser in an ADP crystal.

PubMed

Ji, Shaohua; Wang, Fang; Zhu, Lili; Xu, Xinguang; Wang, Zhengping; Sun, Xun

2013-01-01

In current inertial confinement fusion (ICF) facilities, KDP and DKDP crystals are the second harmonic generation (SHG) and third harmonic generation (THG) materials for the Nd:glass laser (1053 nm). Based on the trend for the development of short wavelengths for ICF driving lasers, technical solutions for fourth harmonic generation (FHG) will undoubtedly attract more and more attention. In this paper, the rapid growth of an ADP crystal and non-critical phase-matching (NCPM) FHG of a 1053-nm laser using an ADP crystal are reported. The NCPM temperature is 33.7°C. The conversion efficiency from 526 to 263 nm is 70%, and the angular acceptance range is 55.4 mrad; these results are superior to those for the DKDP crystals. This research has shown that ADP crystals will be a competitive candidate in future ICF facilities when the utilisation of high-energy, high-efficiency UV lasers at wavelengths shorter than the present 351 nm is of interest.

Recovery of fissile materials from nuclear wastes

DOEpatents

Forsberg, Charles W.

1999-01-01

A process for recovering fissile materials such as uranium, and plutonium, and rare earth elements, from complex waste feed material, and converting the remaining wastes into a waste glass suitable for storage or disposal. The waste feed is mixed with a dissolution glass formed of lead oxide and boron oxide resulting in oxidation, dehalogenation, and dissolution of metal oxides. Carbon is added to remove lead oxide, and a boron oxide fusion melt is produced. The fusion melt is essentially devoid of organic materials and halogens, and is easily and rapidly dissolved in nitric acid. After dissolution, uranium, plutonium and rare earth elements are separated from the acid and recovered by processes such as PUREX or ion exchange. The remaining acid waste stream is vitrified to produce a waste glass suitable for storage or disposal. Potential waste feed materials include plutonium scrap and residue, miscellaneous spent nuclear fuel, and uranium fissile wastes. The initial feed materials may contain mixtures of metals, ceramics, amorphous solids, halides, organic material and other carbon-containing material.

Commercial objectives, technology transfer, and systems analysis for fusion power development

NASA Astrophysics Data System (ADS)

Dean, Stephen O.

1988-03-01

Fusion is an essentially inexhaustible source of energy that has the potential for economically attractive commercial applications with excellent safety and environmental characteristics. The primary focus for the fusion-energy development program is the generation of centralstation electricity. Fusion has the potential, however, for many other applications. The fact that a large fraction of the energy released in a DT fusion reaction is carried by high-energy neutrons suggests potentially unique applications. These include breeding of fissile fuels, production of hydrogen and other chemical products, transmutation or “burning” of various nuclear or chemical wastes, radiation processing of materials, production of radioisotopes, food preservation, medical diagnosis and medical treatment, and space power and space propulsion. In addition, fusion R&D will lead to new products and new markets. Each fusion application must meet certain standards of economic and safety and environmental attractiveness. For this reason, economics on the one hand, and safety and environment and licensing on the other hand, are the two primary criteria for setting long-range commercial fusion objectives. A major function of systems analysis is to evaluate the potential of fusion against these objectives and to help guide the fusion R&D program toward practical applications. The transfer of fusion technology and skills from the national laboratories and universities to industry is the key to achieving the long-range objective of commercial fusion applications.

Active Neutron-Based Interrogation System with D-D Neutron Source for Detection of Special Nuclear Materials

NASA Astrophysics Data System (ADS)

Takahashi, Y.; Misawa, T.; Yagi, T.; Pyeon, C. H.; Kimura, M.; Masuda, K.; Ohgaki, H.

2015-10-01

The detection of special nuclear materials (SNM) is an important issue for nuclear security. The interrogation systems used in a sea port and an airport are developed in the world. The active neutron-based interrogation system is the one of the candidates. We are developing the active neutron-based interrogation system with a D-D fusion neutron source for the nuclear security application. The D-D neutron source is a compact discharge-type fusion neutron source called IEC (Inertial-Electrostatic Confinement fusion) device which provides 2.45 MeV neutrons. The nuclear materials emit the highenergy neutrons by fission reaction. High-energy neutrons with energies over 2.45 MeV amount to 30% of all the fission neutrons. By using the D-D neutron source, the detection of SNMs is considered to be possible with the attention of fast neutrons if there is over 2.45 MeV. Ideally, neutrons at En>2.45 MeV do not exist if there is no nuclear materials. The detection of fission neutrons over 2.45 MeV are hopeful prospect for the detection of SNM with a high S/N ratio. In the future, the experiments combined with nuclear materials and a D-D neutron source will be conducted. Furthermore, the interrogation system will be numerically investigated by using nuclear materials, a D-D neutron source, and a steel container.

Myogenin, AP2β, NOS-1, and HMGA2 are surrogate markers of fusion status in rhabdomyosarcoma: a report from the soft tissue sarcoma committee of the children's oncology group.

PubMed

Rudzinski, Erin R; Anderson, James R; Lyden, Elizabeth R; Bridge, Julia A; Barr, Frederic G; Gastier-Foster, Julie M; Bachmeyer, Karen; Skapek, Stephen X; Hawkins, Douglas S; Teot, Lisa A; Parham, David M

2014-05-01

Pediatric rhabdomyosarcoma (RMS) is traditionally classified on the basis of the histologic appearance into alveolar (ARMS) and embryonal (ERMS) subtypes. The majority of ARMS contain a PAX3-FOXO1 or PAX7-FOXO1 gene fusion, but about 20% do not. Intergroup Rhabdomyosarcoma Study stage-matched and group-matched ARMS typically behaves more aggressively than ERMS, but recent studies have shown that it is, in fact, the fusion status that drives the outcome for RMS. Gene expression microarray data indicate that several genes discriminate between fusion-positive and fusion-negative RMS with high specificity. Using tissue microarrays containing a series of both ARMS and ERMS, we identified a panel of 4 immunohistochemical markers-myogenin, AP2β, NOS-1, and HMGA2-which can be used as surrogate markers of fusion status in RMS. These antibodies provide an alternative to molecular methods for identification of fusion-positive RMS, particularly in cases in which there is scant or poor-quality material. In addition, these antibodies may be useful in fusion-negative ARMS as an indicator that a variant gene fusion may be present.

Ten-Step Minimally Invasive Spine Lumbar Decompression and Dural Repair Through Tubular Retractors.

PubMed

Boukebir, Mohamed Abdelatif; Berlin, Connor David; Navarro-Ramirez, Rodrigo; Heiland, Tim; Schöller, Karsten; Rawanduzy, Cameron; Kirnaz, Sertaç; Jada, Ajit; Härtl, Roger

2017-04-01

Minimally invasive spine (MIS) surgery utilizing tubular retractors has become an increasingly popular approach for decompression in the lumbar spine. However, a better understanding of appropriate indications, efficacious surgical techniques, limitations, and complication management is required to effectively teach the procedure and to facilitate the learning curve. To describe our experience and recommendations regarding tubular surgery for lumbar disc herniations, foraminal compression with unilateral radiculopathy, lumbar spinal stenosis, synovial cysts, and dural repair. We reviewed our experience between 2008 and 2014 to develop a step-by-step description of the surgical techniques and complication management, including dural repair through tubes, for the 4 lumbar pathologies of highest frequency. We provide additional supplementary videos for dural tear repair, laminotomy for bilateral decompression, and synovial cyst resection. Our overview and complementary materials document the key technical details to maximize the success of the 4 MIS surgical techniques. The review of our experience in 331 patients reveals technical feasibility as well as satisfying clinical results, with no postoperative complications associated with cerebrospinal fluid leaks, 1 infection, and 17 instances (5.1%) of delayed fusion. MIS surgery through tubular retractors is a safe and effective alternative to traditional open or microsurgical techniques for the treatment of lumbar degenerative disease. Adherence to strict microsurgical techniques will allow the surgeon to effectively address bilateral pathology while preserving stability and minimizing complications. Copyright © 2017 by the Congress of Neurological Surgeons

Silica Fiber Lasers and Amplifiers as Pump Sources for Frequency Conversion

DTIC Science & Technology

2010-09-01

compared to non-pedestal LMA designs • NAs of 0.1 have been achieved • Disadvantages: • Additional glass material in the fiber • Fusion splicing issues...Disadvantages: • Additional glass material in the fiber • Fusion splicing issues (4 glasses in a PM fiber ) • NA cannot be reduced indefinitely • Limits...converted in a nonlinear crystal • Typically ZGP, PPLN, OPGaAs • How can we use fiber with Mid-IR light • We can use it to transport Mid-IR light over

Gene Fusion: A Genome Wide Survey

NASA Technical Reports Server (NTRS)

Liang, Ping; Riley, Monica

2001-01-01

As a well known fact, organisms form larger and complex multimodular (composite or chimeric) and mostly multi-functional proteins through gene fusion of two or more individual genes which have independent evolution histories and functions. We call each of these components a module. The existence of multimodular proteins may improves the efficiency in gene regulation and in cellular functions, and thus may give the host organism advantages in adaptation to environments. Analysis of all gene fusions in present-day organisms should allow us to examine the patterns of gene fusion in context with cellular functions, to trace back the evolution processes from the ancient smaller and uni-functional proteins to the present-day larger and complex multi-functional proteins, and to estimate the minimal number of ancestor proteins that existed in the last common ancestor for all life on earth. Although many multimodular proteins have been experimentally known, identification of gene fusion events systematically at genome scale had not been possible until recently when large number of completed genome sequences have been becoming available. In addition, technical difficulties for such analysis also exist due to the complexity of this biological and evolutionary process. We report from this study a new strategy to computationally identify multimodular proteins using completed genome sequences and the results surveyed from 22 organisms with the data from over 40 organisms to be presented during the meeting. Additional information is contained in the original extended abstract.

Metafusion: A breakthrough in metallurgy

NASA Technical Reports Server (NTRS)

Joseph, Adrian A.

1994-01-01

The Metafuse Process is a patented development in the field of thin film coatings utilizing cold fusion which results in a true inter-dispersion of dissimilar materials along a gradual transition gradient through a boundary of several hundred atomic layers. The process is performed at ambient temperatures and pressures requiring relatively little energy and creating little or no heat. The process permits a remarkable range of material combinations and joining of materials which are normally incompatible. Initial applications include titanium carbide into and onto the copper resistance welding electrodes and tungsten carbide onto the cutting edges of tool steel blades. The process is achieved through application of an RF signal of low power and is based on the theory of vacancy fusion.

Fusion Energy Division progress report, 1 January 1990--31 December 1991

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sheffield, J.; Baker, C.C.; Saltmarsh, M.J.

1994-03-01

The Fusion Program of the Oak Ridge National Laboratory (ORNL), a major part of the national fusion program, encompasses nearly all areas of magnetic fusion research. The program is directed toward the development of fusion as an economical and environmentally attractive energy source for the future. The program involves staff from ORNL, Martin Marietta Energy systems, Inc., private industry, the academic community, and other fusion laboratories, in the US and abroad. Achievements resulting from this collaboration are documented in this report, which is issued as the progress report of the ORNL Fusion Energy Division; it also contains information from componentsmore » for the Fusion Program that are external to the division (about 15% of the program effort). The areas addressed by the Fusion Program include the following: experimental and theoretical research on magnetic confinement concepts; engineering and physics of existing and planned devices, including remote handling; development and testing of diagnostic tools and techniques in support of experiments; assembly and distribution to the fusion community of databases on atomic physics and radiation effects; development and testing of technologies for heating and fueling fusion plasmas; development and testing of superconducting magnets for containing fusion plasmas; development and testing of materials for fusion devices; and exploration of opportunities to apply the unique skills, technology, and techniques developed in the course of this work to other areas (about 15% of the Division`s activities). Highlights from program activities during 1990 and 1991 are presented.« less

Chondroitin sulphate-mediated fusion of brain neural folds in rat embryos.

PubMed

Alonso, M I; Moro, J A; Martín, C; de la Mano, A; Carnicero, E; Martínez-Alvarez, C; Navarro, N; Cordero, J; Gato, A

2009-01-01

Previous studies have demonstrated that during neural fold fusion in different species, an apical extracellular material rich in glycoconjugates is involved. However, the composition and the biological role of this material remain undetermined. In this paper, we show that this extracellular matrix in rat increases notably prior to contact between the neural folds, suggesting the dynamic behaviour of the secretory process. Immunostaining has allowed us to demonstrate that this extracellular matrix contains chondroitin sulphate proteoglycan (CSPG), with a spatio-temporal distribution pattern, suggesting a direct relationship with the process of adhesion. The degree of CSPG involvement in cephalic neural fold fusion in rat embryos was determined by treatment with specific glycosidases.In vitro rat embryo culture and microinjection techniques were employed to carry out selective digestion, with chondroitinase AC, of the CSPG on the apical surface of the neural folds; this was done immediately prior to the bonding of the cephalic neural folds. In all the treated embryos, cephalic defects of neural fold fusion could be detected. These results show that CSPG plays an important role in the fusion of the cephalic neural folds in rat embryos, which implies that this proteoglycan could be involved in cellular recognition and adhesion. (c) 2008 S. Karger AG, Basel.

Ultrafast-electron-diffraction studies of predamaged tungsten excited by femtosecond optical pulses

NASA Astrophysics Data System (ADS)

Mo, M.; Chen, Z.; Li, R.; Wang, Y.; Shen, X.; Dunning, M.; Weathersby, S.; Makasyuk, I.; Coffee, R.; Zhen, Q.; Kim, J.; Reid, A.; Jobe, K.; Hast, C.; Tsui, Y.; Wang, X.; Glenzer, S.

2016-10-01

Tungsten is considered as the main candidate material for use in the divertor of magnetic confinement fusion reactors. However, radiation damage is expected to occur because of its direct exposure to the high flux of hot plasma and energetic neutrons in fusion environment. Hence, understanding the material behaviors of W under these adverse conditions is central to the design of magnetic fusion reactors. To do that, we have recently developed an MeV ultrafast electron diffraction probe to resolve the structural evolution of optically excited tungsten. To simulate the radiation damage effect, the tungsten samples were bombarded with 500 keV Cu ions. The pre-damaged and pristine W's were excited by 130fs, 400nm laser pulses, and the subsequent heated system was probed with 3.2MeV electrons. The pump probe measurement shows that the ion bombardment to the W leads to larger decay in Bragg peak intensities as compared to pristine W, which may be due to a phonon softening effect. The measurement also shows that pre-damaged W transitions into complete liquid phase for conditions where pristine W stays solid. Our new capability is able to test the theories of structural dynamics of W under conditions relevant to fusion reactor environment. The research was funded by DOE Fusion Energy Science under FWP #100182.

The use of 3D image fusion for percutaneous transluminal angioplasty and stenting of iliac artery obstructions: validation of the technique and systematic review of literature.

PubMed

Goudeketting, Seline R; Heinen, Stefan G; van den Heuvel, Daniel A; van Strijen, Marco J; de Haan, Michiel W; Slump, Cornelis H; de Vries, Jean-Paul P

2018-02-01

The effect of the insertion of guidewires and catheters on fusion accuracy of the three-dimensional (3D) image fusion technique during iliac percutaneous transluminal angioplasty (PTA) procedures has not yet been investigated. Technical validation of the 3D fusion technique was evaluated in 11 patients with common and/or external iliac artery lesions. A preprocedural contrast-enhanced magnetic resonance angiogram (CE-MRA) was segmented and manually registered to a cone-beam computed tomography image created at the beginning of the procedure for each patient. The treating physician visually scored the fusion accuracy (i.e., accurate [<2 mm], mismatch [2-5 mm], or inaccurate [>5 mm]) of the entire vasculature of the overlay with respect to the digital subtraction angiography (DSA) directly after the first obtained DSA. Contours of the vasculature of the fusion images and DSAs were drawn after the procedure. The cranial-caudal, lateral-medial, and absolute displacement were calculated between the vessel centerlines. To determine the influence of the catheters, displacement of the catheterized iliac trajectories were compared with the noncatheterized trajectories. Electronic databases were systematically searched for available literature published between January 2010 till August 2017. The mean registration error for all iliac trajectories (N.=20) was small (4.0±2.5 mm). No significant difference in fusion displacement was observed between catheterized (N.=11) and noncatheterized (N.=9) iliac arteries. The systematic literature search yielded 2 manuscripts with a total of 22 patients. The methodological quality of these studies was poor (≤11 MINORS Score), mainly due to a lack of a control group. Accurate image fusion based on preprocedural CE-MRA is possible and could potentially be of help in iliac PTA procedures. The flexible guidewires and angiographic catheters, routinely used during endovascular procedures of iliac arteries, did not cause significant displacement that influenced the image fusion. Current literature on 3D image fusion in iliac PTA procedures is of limited methodological quality.

Application of a narrow-surface cage in full endoscopic minimally invasive transforaminal lumbar interbody fusion.

PubMed

He, Er-Xing; Guo, Jing; Ling, Qin-Jie; Yin, Zhi-Xun; Wang, Ying; Li, Ming

2017-06-01

Spinal endoscopy has been widely applied in lumbar discectomy and decompression. However, endoscopic lumbar interbody fusion still remains a technical challenge due to the limited space within the working trocar for cage implantation. The purpose of this study was to investigate the feasibility and effectiveness of using a narrow-surface fusion cage in full endoscopic minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for the treatment of lumbar degenerative disease. From Jun 2013 to Dec 2014, a total of 42 patients (23 males, 19 females) underwent full endoscopic MIS-TLIF at our hospital was recruited. An 8-mm-wide narrow-surface fusion cage was selected for all cases. Perioperative parameters and complications were recorded. Comparisons on visual analog scale (VAS) and oswestry disability index (ODI) scores before and after surgery were performed. At the last follow-up, Nakai grading system was applied to assess patients' satisfaction; meanwhile, interbody fusion was evaluated by computed tomography. Mean operation time was 233.1 ± 69.5 min, and mean blood loss during surgery was 221.8 ± 98.5 ml. Two patients (4.8%) developed neurological complications. Postoperative follow-up ranged from 24 to 36 months (mean 27.6 ± 3.8 months). VAS and ODI scores were significantly improved 3 months after surgery and at the final follow-up, respectively (P < 0.05). Outcome of surgery was graded as excellent for 32 patients, good for 8 patients, and acceptable for 2 patients, corresponding to a success rate ("good" and "excellent") of 95.2%. Thirty-nine of the 42 patients demonstrated solid interbody fusion at the last follow-up, indicating a fusion rate of 92.9%. Application of a narrow-surface fusion cage in full endoscopic MIS-TLIF for the treatment of lumbar degenerative disease is feasible and effective. The clinical outcome and fusion success of this procedure were acceptable and promising. Copyright © 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Editorial note

NASA Astrophysics Data System (ADS)

Degueldre, Claude; Lee, Bill; Oversby, Virginia; van Walle, Eric

2009-03-01

The 3rd Symposium N on Nuclear Materials of the European Material Research Society (EMRS) held at the EMRS 08 Spring meeting; Strasbourg - May 26-30, 2008, involved 125 experts from 19 countries dealing with specific nuclear topics in the following sessions: Materials for advanced fusion systems.

Construction demolition wastes, Waelz slag and MSWI bottom ash: a comparative technical analysis as material for road construction.

PubMed

Vegas, I; Ibañez, J A; San José, J T; Urzelai, A

2008-01-01

The objective of the study is to analyze the technical suitability of using secondary materials from three waste flows (construction and demolition waste (CDW), Waelz slag and municipal solid waste incineration (MSWI) bottom ash), under the regulations and standards governing the use of materials for road construction. A detailed technical characterization of the materials was carried out according to Spanish General Technical Specifications for Road Construction (PG3). The results show that Waelz slag can be adequate for using in granular structural layers, while CDW fits better as granular material in roadbeds. Likewise, fresh MSWI bottom ash can be used as roadbed material as long as it does not contain a high concentration of soluble salts. This paper also discusses the adequacy of using certain traditional test methods for natural soils when characterizing secondary materials for use as aggregates in road construction.

Close-out report with links to abstracts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marmar, Earl S.

This grant provided A/V support for two technical meetings of the Edge Coordinating Committee: (1) Nov 13, 2013 (co-located with the APS-DPP meeting in Denver, CO) https://ecc.mit.edu/fall-2013-technical-meeting#overlay-context=ecc-meetings; (2) April 28-May 1, 2015 (embedded sessions in the Transport Task Force Meeting, Salem, MA) http://www-internal.psfc.mit.edu/TTF2015/index.html. The ultimate goal of the U.S. Transport Task Force is to develop a physics-based understanding of particle, momentum and heat transport in magnetic fusion devices. This understanding should be of sufficient depth that it allows the development of predictive models of plasma transport that can be validated against experiment, and then used to anticipate the future performancemore » of burning plasmas in ITER, as well as to provide guidance for the design of next-step fusion nuclear science facilities. To achieve success in transport science, it is essential to characterize local fluctuations and transport in toroidal plasmas, to understand the basic mechanisms responsible for transport, and ultimately to control these transport processes. These goals must be pursued in multiple areas, and these topics evolve in order to reflect current interests.« less

Technical Education Outreach in Materials Science and Technology Based on NASA's Materials Research

NASA Technical Reports Server (NTRS)

Jacobs, James A.

2003-01-01

The grant NAG-1 -2125, Technical Education Outreach in Materials Science and Technology, based on NASA s Materials Research, involves collaborative effort among the National Aeronautics and Space Administration s Langley Research Center (NASA-LaRC), Norfolk State University (NSU), national research centers, private industry, technical societies, colleges and universities. The collaboration aims to strengthen math, science and technology education by providing outreach related to materials science and technology (MST). The goal of the project is to transfer new developments from LaRC s Center for Excellence for Structures and Materials and other NASA materials research into technical education across the nation to provide educational outreach and strengthen technical education. To achieve this goal we are employing two main strategies: 1) development of the gateway website and 2) using the National Educators Workshop: Update in Engineering Materials, Science and Technology (NEW:Updates). We have also participated in a number of national projects, presented talks at technical meetings and published articles aimed at improving k-12 technical education. Through the three years of this project the NSU team developed the successful MST-Online site and continued to upgrade and update it as our limited resources permitted. Three annual NEW:Updates conducted from 2000 though 2002 overcame the challenges presented first by the September 11,2001 terrorist attacks and the slow U.S. economy and still managed to conduct very effective workshops and expand our outreach efforts. Plans began on NEW:Update 2003 to be hosted by NASA Langley as a part of the celebration of the Centennial of Controlled Flight.

Parasol: An Architecture for Cross-Cloud Federated Graph Querying

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lieberman, Michael; Choudhury, Sutanay; Hughes, Marisa

2014-06-22

Large scale data fusion of multiple datasets can often provide in- sights that examining datasets individually cannot. However, when these datasets reside in different data centers and cannot be collocated due to technical, administrative, or policy barriers, a unique set of problems arise that hamper querying and data fusion. To ad- dress these problems, a system and architecture named Parasol is presented that enables federated queries over graph databases residing in multiple clouds. Parasol’s design is flexible and requires only minimal assumptions for participant clouds. Query optimization techniques are also described that are compatible with Parasol’s lightweight architecture. Experiments onmore » a prototype implementation of Parasol indicate its suitability for cross-cloud federated graph queries.« less

Ion-ion charge exchange processes. Final technical report, June 1, 1977-May 31, 1978

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poe, R.T.; Choi, B.H.

Under the auspices of ERDA, we have undertaken a vigorous study of ion-ion charge exchange process pertinent to the storage-ring configurations in the heavy-ion fusion program. One particular reaction, singly charged helium charge exchange, was investigated in detail. General trend of the singly charged heavy-ion charge exchange reaction can be inferred from the present study. Some of our results were presented at Proceedings of the Heavy-Ion Fusion Workshop, Argonne National Laboratory (September 1978) as a paper entitled Charge Exchange Between Singly Ionized Helium Ions, by B.H. Choi, R.T. Poe and K.T. Tang. Here, we briefly describe our method and reportmore » the results.« less

BOOK REVIEW: Fusion: The Energy of the Universe

NASA Astrophysics Data System (ADS)

Lister, J.

2006-05-01

This book outlines the quest for fusion energy. It is presented in a form which is accessible to the interested layman, but which is precise and detailed for the specialist as well. The book contains 12 detailed chapters which cover the whole of the intended subject matter with copious illustrations and a balance between science and the scientific and political context. In addition, the book presents a useful glossary and a brief set of references for further non-specialist reading. Chapters 1 to 3 treat the underlying physics of nuclear energy and of the reactions in the sun and in the stars in considerable detail, including the creation of the matter in the universe. Chapter 4 presents the fusion reactions which can be harnessed on earth, and poses the fundamental problems of realising fusion energy as a source for our use, explaining the background to the Lawson criterion on the required quality of energy confinement, which 50 years later remains our fundamental milestone. Chapter 5 presents the basis for magnetic confinement, introducing some early attempts as well as some straightforward difficulties and treating linear and circular devices. The origins of the stellarator and of the tokamak are described. Chapter 6 is not essential to the mission of usefully harnessing fusion energy, but nonetheless explains to the layman the difference between fusion and fission in weapons, which should help the readers understand the differences as sources of peaceful energy as well, since this popular confusion remains a problem when proposing fusion with the `nuclear' label. Chapter 7 returns to energy sources with laser fusion, or inertial confinement fusion, which constitutes both military and civil research, depending on the country. The chapter provides a broad overview of the progress right up to today's hopes for fast ignition. The difficulty of harnessing fusion energy by magnetic or inertial confinement has created a breeding ground for what the authors call `false trails', since it is so tempting to produce a `backroom' solution to mankind's hunger for energy. Unfortunately, Chapter 8 can only regret that none of them has passed closer peer review. Chapters 9 and 10 concentrate on the `tokamak' concept for magnetic confinement, the basis for the JET and ITER projects, as well as for a wealth of smaller, national projects. The hopes and the disappointments are well and very frankly illustrated. The motivation for building a project of the size of ITER is made very clear. Present fusion research cannot forget that its mission is to develop an industrial reactor, not just a powerful research tool. Chapter 11 presents the major challenges between ITER and a reactor. Finally, Chapter 12 reminds us of why we need energy, why we do not have a credible solution at the mid-term (20 years) and why we have no solution in the longer term. The public awareness of this is growing, at last, even though the arguments were all on the table in the 1970's. This chapter therefore closes the book by bringing the reader back to earth rather suitably with the hard reality of energy needs and the absence of credible policies. This book has already received impressive approval among a wide range of people, since it so evidently succeeds in its goal to explain Fusion to many levels of reader. Gary McCracken and Peter Stott (one time editor of Plasma Physics and Controlled Fusion) both dedicated their careers to magnetic confinement fusion, mostly at Culham working on UKAEA projects and later on the JET project. They were both deeply involved with international collaborations and both were working abroad when they retired. The mixture between ideas, developments and people is most successfully developed. They clearly underline the importance of strong international collaboration on which this field depends. This open background is tangible in their recently published work, in which they have tried to communicate their love and understanding of this exciting field to the non-specialist. Their attempt has resulted in a remarkable success, filling a hole in the available literature. The format of this book, with boxed technical details, allows the casual reader to browse without being trapped by excessive detail, whereas the information is still there for the more assiduous reader. The only technical fault is the marring of the presentation by some unresolved production details in chapter 10. With the long-awaited decision to site ITER in Europe, there will inevitably be a strong demand for more information on fusion research for non-specialists, simply to understand what is behind this large project. This book fits the bill. It is written with technical accuracy but without resort to mathematics—a notably tricky target. The non-specialist wishing to find out about the field of fusion research, whether working as a journalist, administrator, secretary, politician, engineer or technician, will find a wealth of detail expressed in an accessible language. The specialist will be surprised by the precision of the text, and by the depth of the historical basis to this research. He will learn much, even if he is already familiar with the current state of art of fusion research. The younger researchers will find a clear history of their chosen field. The reviewer knows of no other book which has met this difficult goal with such ease, and strongly recommends it for the educated layman as well as for the ITER generation of younger physicists who did not live through the evolutionary period of fusion research, with its doubts, disappointments and successes.

Progress In Magnetized Target Fusion Driven by Plasma Liners

NASA Technical Reports Server (NTRS)

Thio, Francis Y. C.; Kirkpatrick, Ronald C.; Knapp, Charles E.; Cassibry, Jason; Eskridge, Richard; Lee, Michael; Smith, James; Martin, Adam; Wu, S. T.; Schmidt, George;

Recombinant spider silk genetically functionalized with affinity domains.

PubMed

Jansson, Ronnie; Thatikonda, Naresh; Lindberg, Diana; Rising, Anna; Johansson, Jan; Nygren, Per-Åke; Hedhammar, My

2014-05-12

Functionalization of biocompatible materials for presentation of active protein domains is an area of growing interest. Herein, we describe a strategy for functionalization of recombinant spider silk via gene fusion to affinity domains of broad biotechnological use. Four affinity domains of different origin and structure; the IgG-binding domains Z and C2, the albumin-binding domain ABD, and the biotin-binding domain M4, were all successfully produced as soluble silk fusion proteins under nondenaturing purification conditions. Silk films and fibers produced from the fusion proteins were demonstrated to be chemically and thermally stable. Still, the bioactive domains are concluded to be folded and accessible, since their respective targets could be selectively captured from complex samples, including rabbit serum and human plasma. Interestingly, materials produced from mixtures of two different silk fusion proteins displayed combined binding properties, suggesting that tailor-made materials with desired stoichiometry and surface distributions of several binding domains can be produced. Further, use of the IgG binding ability as a general mean for presentation of desired biomolecules could be demonstrated for a human vascular endothelial growth factor (hVEGF) model system, via a first capture of anti-VEGF IgG to silk containing the Z-domain, followed by incubation with hVEGF. Taken together, this study demonstrates the potential of recombinant silk, genetically functionalized with affinity domains, for construction of biomaterials capable of presentation of almost any desired biomolecule.

Clinical Application of Ceramics in Anterior Cervical Discectomy and Fusion: A Review and Update.

PubMed

Zadegan, Shayan Abdollah; Abedi, Aidin; Jazayeri, Seyed Behnam; Bonaki, Hirbod Nasiri; Vaccaro, Alexander R; Rahimi-Movaghar, Vafa

2017-06-01

Narrative review. Anterior cervical discectomy and fusion (ACDF) is a reliable procedure, commonly used for cervical degenerative disc disease. For interbody fusions, autograft was the gold standard for decades; however, limited availability and donor site morbidities have led to a constant search for new materials. Clinically, it has been shown that calcium phosphate ceramics, including hydroxyapatite (HA) and tricalcium phosphate (TCP), are effective as osteoconductive materials and bone grafts. In this review, we present the current findings regarding the use of ceramics in ACDF. A review of the relevant literature examining the clinical use of ceramics in anterior cervical discectomy and fusion procedures was conducted using PubMed, OVID and Cochrane. HA, coralline HA, sandwiched HA, TCP, and biphasic calcium phosphate ceramics were used in combination with osteoinductive materials such as bone marrow aspirate and various cages composed of poly-ether-ether-ketone (PEEK), fiber carbon, and titanium. Stand-alone ceramic spacers have been associated with fracture and cracks. Metallic cages such as titanium endure the risk of subsidence and migration. PEEK cages in combination with ceramics were shown to be a suitable substitute for autograft. None of the discussed options has demonstrated clear superiority over others, although direct comparisons are often difficult due to discrepancies in data collection and study methodologies. Future randomized clinical trials are warranted before definitive conclusions can be drawn.

Does PEEK/HA Enhance Bone Formation Compared With PEEK in a Sheep Cervical Fusion Model?

PubMed

Walsh, William R; Pelletier, Matthew H; Bertollo, Nicky; Christou, Chris; Tan, Chris

2016-11-01

Polyetheretherketone (PEEK) has a wide range of clinical applications but does not directly bond to bone. Bulk incorporation of osteoconductive materials including hydroxyapatite (HA) into the PEEK matrix is a potential solution to address the formation of a fibrous tissue layer between PEEK and bone and has not been tested. Using in vivo ovine animal models, we asked: (1) Does PEEK-HA improve cortical and cancellous bone ongrowth compared with PEEK? (2) Does PEEK-HA improve bone ongrowth and fusion outcome in a more challenging functional ovine cervical fusion model? The in vivo responses of PEEK-HA Enhanced and PEEK-OPTIMA ® Natural were evaluated for bone ongrowth in the form of dowels implanted in the cancellous and cortical bone of adult sheep and examined at 4 and 12 weeks as well as interbody cervical fusion at 6, 12, and 26 weeks. The bone-implant interface was evaluated with radiographic and histologic endpoints for a qualitative assessment of direct bone contact of an intervening fibrous tissue later. Gamma-irradiated cortical allograft cages were evaluated as well. Incorporating HA into the PEEK matrix resulted in more direct bone apposition as opposed to the fibrous tissue interface with PEEK alone in the bone ongrowth as well as interbody cervical fusions. No adverse reactions were found at the implant-bone interface for either material. Radiography and histology revealed resorption and fracture of the allograft devices in vivo. Incorporating HA into PEEK provides a more favorable environment than PEEK alone for bone ongrowth. Cervical fusion was improved with PEEK-HA compared with PEEK alone as well as allograft bone interbody devices. Improving the bone-implant interface with a PEEK device by incorporating HA may improve interbody fusion results and requires further clinical studies.

Intense fusion neutron sources

NASA Astrophysics Data System (ADS)

Kuteev, B. V.; Goncharov, P. R.; Sergeev, V. Yu.; Khripunov, V. I.

2010-04-01

The review describes physical principles underlying efficient production of free neutrons, up-to-date possibilities and prospects of creating fission and fusion neutron sources with intensities of 1015-1021 neutrons/s, and schemes of production and application of neutrons in fusion-fission hybrid systems. The physical processes and parameters of high-temperature plasmas are considered at which optimal conditions for producing the largest number of fusion neutrons in systems with magnetic and inertial plasma confinement are achieved. The proposed plasma methods for neutron production are compared with other methods based on fusion reactions in nonplasma media, fission reactions, spallation, and muon catalysis. At present, intense neutron fluxes are mainly used in nanotechnology, biotechnology, material science, and military and fundamental research. In the near future (10-20 years), it will be possible to apply high-power neutron sources in fusion-fission hybrid systems for producing hydrogen, electric power, and technological heat, as well as for manufacturing synthetic nuclear fuel and closing the nuclear fuel cycle. Neutron sources with intensities approaching 1020 neutrons/s may radically change the structure of power industry and considerably influence the fundamental and applied science and innovation technologies. Along with utilizing the energy produced in fusion reactions, the achievement of such high neutron intensities may stimulate wide application of subcritical fast nuclear reactors controlled by neutron sources. Superpower neutron sources will allow one to solve many problems of neutron diagnostics, monitor nano-and biological objects, and carry out radiation testing and modification of volumetric properties of materials at the industrial level. Such sources will considerably (up to 100 times) improve the accuracy of neutron physics experiments and will provide a better understanding of the structure of matter, including that of the neutron itself.

TECHNICAL BASIS FOR A CANDIDATE BUILDING MATERIALS RADIUM STANDARD

EPA Science Inventory

The report summarizes the technical basis for a candidate building materials radium standard. It contains the standard and a summary of the technical basis for the standard. (NOTE: The Florida Radon Research Program (FRRP), sponsored by the Environmental Protection Agency and the...

Automotive Fuel Economy: A Technical Study and Curriculum Development Project. A Thesis Presented to the Faculty of the College of Education, Mankato State University.

ERIC Educational Resources Information Center

Ready, Kirk Lewis

Automotive fuel economy was the topic of a study during which technical and background information was gathered, curriculum materials were sought, and curricula were developed. Technical information came from written materials and actual mileage tests of selected factors. Background came from written materials, field trips, and building and…

[Discussion on Technical Evaluation for Medical Device Registration Material].

PubMed

Chu, Yungao; Qian, Hong; Zhu, Yingfeng

2017-07-30

This article first introduces the main contents of the requirements for medical device registration. Secondly, this article chooses the vertebral forming surgery system as an example to discuss the technical evaluation for the registration research material. The article hopes to provide a reference for the applicant who prepare the registration material and the technical evaluator who make the evaluation for the medical device registration.

Multiplier, moderator, and reflector materials for lithium-vanadium fusion blankets.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gohar, Y.; Smith, D. L.

1999-10-07

The self-cooled lithium-vanadium fusion blanket concept has several attractive operational and environmental features. In this concept, liquid lithium works as the tritium breeder and coolant to alleviate issues of coolant breeder compatibility and reactivity. Vanadium alloy (V-4Cr-4Ti) is used as the structural material because of its superior performance relative to other alloys for this application. However, this concept has poor attenuation characteristics and energy multiplication for the DT neutrons. An advanced self-cooled lithium-vanadium fusion blanket concept has been developed to eliminate these drawbacks while maintaining all the attractive features of the conventional concept. An electrical insulator coating for the coolantmore » channels, spectral shifter (multiplier, and moderator) and reflector were utilized in the blanket design to enhance the blanket performance. In addition, the blanket was designed to have the capability to operate at high loading conditions of 2 MW/m{sup 2} surface heat flux and 10 MW/m{sup 2} neutron wall loading. This paper assesses the spectral shifter and the reflector materials and it defines the technological requirements of this advanced blanket concept.« less

Multiplier, moderator, and reflector materials for advanced lithium?vanadium fusion blankets

NASA Astrophysics Data System (ADS)

Gohar, Y.; Smith, D. L.

2000-12-01

The self-cooled lithium-vanadium fusion blanket concept has several attractive operational and environmental features. In this concept, liquid lithium works as the tritium breeder and coolant to alleviate issues of coolant breeder compatibility and reactivity. Vanadium alloy (V-4Cr-4Ti) is used as the structural material because of its superior performance relative to other alloys for this application. However, this concept has poor attenuation characteristics and energy multiplication for the DT neutrons. An advanced self-cooled lithium-vanadium fusion blanket concept has been developed to eliminate these drawbacks while maintaining all the attractive features of the conventional concept. An electrical insulator coating for the coolant channels, spectral shifter (multiplier, and moderator) and reflector were utilized in the blanket design to enhance the blanket performance. In addition, the blanket was designed to have the capability to operate at average loading conditions of 2 MW/m 2 surface heat flux and 10 MW/m 2 neutron wall loading. This paper assesses the spectral shifter and the reflector materials and it defines the technological requirements of this advanced blanket concept.

Experiment and Theory for Nuclear Reactions in Nano-Materials Show e14 - e16 Solid-State Fusion Reactions

NASA Astrophysics Data System (ADS)

George, Russ

2005-03-01

Nano-lattices of deuterium loving metals exhibit coherent behavior by populations of deuterons (d's) occupying a Bloch state. Therein, coherent d-overlap occurs wherein the Bloch condition reduces the Coulomb barrier.Overlap of dd pairs provides a high probability fusion will/must occur. SEM photo evidence showing fusion events is now revealed by laboratories that load or flux d into metal nano-domains. Solid-state dd fusion creates an excited ^4He nucleus entangled in the large coherent population of d's.This contrasts with plasma dd fusion in collision space where an isolated excited ^4He nucleus seeks the ground state via fast particle emission. In momentum limited solid state fusion,fast particle emission is effectively forbidden.Photographed nano-explosive events are beyond the scope of chemistry. Corroboration of the nuclear nature derives from photographic observation of similar events on spontaneous fission, e.g. Cf. We present predictive theory, heat production, and helium isotope data showing reproducible e14 to e16 solid-state fusion reactions.

76 FR 29333 - Pipeline Safety: Meetings of the Technical Pipeline Safety Standards Committee and the Technical...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-20

... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration [Docket No... Technical Hazardous Liquid Pipeline Safety Standards Committee AGENCY: Pipeline and Hazardous Materials... for natural gas pipelines and for hazardous liquid pipelines. Both committees were established under...

The Measurement of the Specific Latent Heat of Fusion of Ice: Two Improved Methods.

ERIC Educational Resources Information Center

Mak, S. Y.; Chun, C. K. W.

2000-01-01

Suggests two methods for measuring the specific latent heat of ice fusion for high school physics laboratories. The first method is an ice calorimeter which is made from simple materials. The second method improves the thermal contact and allows for a more accurate measurement. Lists instructions for both methods. (Author/YDS)

Functional materials for breeding blankets—status and developments

NASA Astrophysics Data System (ADS)

Konishi, S.; Enoeda, M.; Nakamichi, M.; Hoshino, T.; Ying, A.; Sharafat, S.; Smolentsev, S.

2017-09-01

The development of tritium breeder, neutron multiplier and flow channel insert materials for the breeding blanket of the DEMO reactor is reviewed. Present emphasis is on the ITER test blanket module (TBM); lithium metatitanate (Li2TiO3) and lithium orthosilicate (Li4SiO4) pebbles have been developed by leading TBM parties. Beryllium pebbles have been selected as the neutron multiplier. Good progress has been made in their fabrication; however, verification of the design by experiments is in the planning stage. Irradiation data are also limited, but the decrease in thermal conductivity of beryllium due to irradiation followed by swelling is a concern. Tests at ITER are regarded as a major milestone. For the DEMO reactor, improvement of the breeder has been attempted to obtain a higher lithium content, and Be12Ti and other beryllide intermetallic compounds that have superior chemical stability have been studied. LiPb eutectic has been considered as a DEMO blanket in the liquid breeder option and is used as a coolant to achieve a higher outlet temperature; a SiC flow channel insert is used to prevent magnetohydrodynamic pressure drop and corrosion. A significant technical gap between ITER TBM and DEMO is recognized, and the world fusion community is working on ITER TBM and DEMO blanket development in parallel.

Waste management for different fusion reactor designs

NASA Astrophysics Data System (ADS)

Rocco, Paolo; Zucchetti, Massimo

2000-12-01

Safety and Environmental Assessment of Fusion Power (SEAFP) waste management studies performed up to 1998 concerned three power tokamak designs. In-vessel structural materials consist of V-alloys or low activation martensitic (LAM) steel; tritium-producing materials are Li 2O, Pb-17Li, Li 4SiO 4 with a Be-multiplier; coolants are helium or water. The strategy chosen reduces permanent radwaste by recycling the in-vessel materials and by clearance of the other structures. Limits of the contact dose rate and specific activity of the waste allowing such options are defined accordingly. SEAFP activities for 1999 enlarge the analysis to three additional reactors with in-vessel structures made with SiC/SiC composites. These materials cannot be recycled due to their form and, according to national regulations of E.C. countries, long-lived activation products hinder near-surface burial (NSB).

The national ignition facility and atomic data

NASA Astrophysics Data System (ADS)

Crandall, David H.

1998-07-01

The National Ignition Facility (NIF) is under construction, capping over 25 years of development of the inertial confinement fusion concept by providing the facility to obtain fusion ignition in the laboratory for the first time. The NIF is a 192 beam glass laser to provide energy controlled in space and time so that a millimeter-scale capsule containing deuterium and tritium can be compressed to fusion conditions. Light transport, conversion of light in frequency, interaction of light with matter in solid and plasma forms, and diagnostics of extreme material conditions on small scale all use atomic data in preparing for use of the NIF. The NIF will provide opportunity to make measurements of atomic data in extreme physical environments related to fusion energy, nuclear weapon detonation, and astrophysics. The first laser beams of NIF should be operational in 2001 and the full facility completed at the end of 2003. NIF is to provide 1.8 megajoule of blue light on fusion targets and is intended to achieve fusion ignition by about the end of 2007. Today's inertial fusion development activities use atomic data to design and predict fusion capsule performance and in non-fusion applications to analyze radiation transport and radiation effects on matter. Conditions investigated involve radiation temperature of hundreds of eV, pressures up to gigabars and time scales of femptoseconds.

Simulations of carbon sputtering in fusion reactor divertor plates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marian, J; Zepeda-Ruiz, L A; Gilmer, G H

2005-10-03

The interaction of edge plasma with material surfaces raises key issues for the viability of the International Thermonuclear Reactor (ITER) and future fusion reactors, including heat-flux limits, net material erosion, and impurity production. After exposure of the graphite divertor plate to the plasma in a fusion device, an amorphous C/H layer forms. This layer contains 20-30 atomic percent D/T bonded to C. Subsequent D/T impingement on this layer produces a variety of hydrocarbons that are sputtered back into the sheath region. We present molecular dynamics (MD) simulations of D/T impacts on amorphous carbon layer as a function of ion energymore » and orientation, using the AIREBO potential. In particular, energies are varied between 10 and 150 eV to transition from chemical to physical sputtering. These results are used to quantify yield, hydrocarbon composition and eventual plasma contamination.« less

System and method for making metallic iron with reduced CO.sub.2 emissions

DOEpatents

Kiesel, Richard F; Englund, David J; Schlichting, Mark; Meehan, John; Crouch, Jeremiah; Wilson, Logan

2014-10-14

A method and system for making metallic iron nodules with reduced CO.sub.2 emissions is disclosed. The method includes: assembling a linear hearth furnace having entry and exit portions, at least a conversion zone and a fusion zone, and a moving hearth adapted to move reducible iron bearing material through the furnace on contiguous hearth sections; assembling a shrouded return substantially free of air ingress extending adjacent at least the conversion and fusion zones of the furnace through which hearth sections can move from adjacent the exit portion to adjacent the entry portion of the furnace; transferring the hearth sections from the furnace to the shrouded return adjacent the exit portion; reducing reducible material in the linear hearth furnace to metallic iron nodules; and transporting gases from at least the fusion zone to the shrouded return to heat the hearth sections while in the shrouded return.

Oxidation/volatilization rates in air for candidate fusion reactor blanket materials, PCA and HT-9

NASA Astrophysics Data System (ADS)

Piet, S. J.; Kraus, H. G.; Neilson, R. M.; Jones, J. L.

1986-11-01

Large uncertainties exist in the quantity of neutron-induced activation products that can be mobilized in potential fusion accidents. The accidental combination of high temperatures and oxidizing conditions might lead to mobilization of a significant amount of activation products from structural materials. Here, the volatilization of constituents of PCA and HT-9 resulting form oxidation in air was investigated. Tests were conducted in flowing air at temperatures from 600 to 1300°C for 1, 5, or 20 h. Elemental volatility was calculated in terms of the weight fraction of the element volatilized from the initial alloy. Molybdenum and manganese were the radiologically significant primary constituents most volatilized, suggesting that molybdenum and manganese should be minimized in fusion steel compositions. Higher chromium content appears beneficial in reducing hazards from mobile activation products. Scanning electron microscopy and energy dispersive spectroscopy were used to study the oxide layer on samples.

A novel method to recover DD fusion proton CR-39 data corrupted by fast ablator ions at OMEGA and the National Ignition Facility

NASA Astrophysics Data System (ADS)

Sutcliffe, G. D.; Milanese, L. M.; Orozco, D.; Lahmann, B.; Gatu Johnson, M.; Séguin, F. H.; Sio, H.; Frenje, J. A.; Li, C. K.; Petrasso, R. D.; Park, H.-S.; Rygg, J. R.; Casey, D. T.; Bionta, R.; Turnbull, D. P.; Huntington, C. M.; Ross, J. S.; Zylstra, A. B.; Rosenberg, M. J.; Glebov, V. Yu.

2016-11-01

CR-39 detectors are used routinely in inertial confinement fusion (ICF) experiments as a part of nuclear diagnostics. CR-39 is filtered to stop fast ablator ions which have been accelerated from an ICF implosion due to electric fields caused by laser-plasma interactions. In some experiments, the filtering is insufficient to block these ions and the fusion-product signal tracks are lost in the large background of accelerated ion tracks. A technique for recovering signal in these scenarios has been developed, tested, and implemented successfully. The technique involves removing material from the surface of the CR-39 to a depth beyond the endpoint of the ablator ion tracks. The technique preserves signal magnitude (yield) as well as structure in radiograph images. The technique is effective when signal particle range is at least 10 μm deeper than the necessary bulk material removal.

A novel method to recover DD fusion proton CR-39 data corrupted by fast ablator ions at OMEGA and the National Ignition Facility.

PubMed

Sutcliffe, G D; Milanese, L M; Orozco, D; Lahmann, B; Gatu Johnson, M; Séguin, F H; Sio, H; Frenje, J A; Li, C K; Petrasso, R D; Park, H-S; Rygg, J R; Casey, D T; Bionta, R; Turnbull, D P; Huntington, C M; Ross, J S; Zylstra, A B; Rosenberg, M J; Glebov, V Yu

2016-11-01

CR-39 detectors are used routinely in inertial confinement fusion (ICF) experiments as a part of nuclear diagnostics. CR-39 is filtered to stop fast ablator ions which have been accelerated from an ICF implosion due to electric fields caused by laser-plasma interactions. In some experiments, the filtering is insufficient to block these ions and the fusion-product signal tracks are lost in the large background of accelerated ion tracks. A technique for recovering signal in these scenarios has been developed, tested, and implemented successfully. The technique involves removing material from the surface of the CR-39 to a depth beyond the endpoint of the ablator ion tracks. The technique preserves signal magnitude (yield) as well as structure in radiograph images. The technique is effective when signal particle range is at least 10 μm deeper than the necessary bulk material removal.

Hazardous Materials Technician. Technical Committee on Occupational Curriculum Development.

ERIC Educational Resources Information Center

Northern Montana Coll., Havre. Montana Center for Vocational Education, Research, Curriculum and Personnel Development.

This document describes Montana's postsecondary curriculum to prepare hazardous materials technicians. Basic general education requirements are described. The technical skills and the knowledge associated with each are listed in the following categories: (1) site assessment; (2) sampling materials; (3) handling materials; (4) recording data; (5)…

Solid-state and fusion resistance spot welding of TD-NiCr sheet

NASA Technical Reports Server (NTRS)

Moore, T. J.

1973-01-01

By using specially processed TD-NiCr sheet in both 0.4-mm (0.015-in.) and 1.6-mm (0.062-in.) thicknesses and carefully selected welding procedures, solid state resistance spot welds were produced which, after postheating at 1200 C, were indistinguishable from the parent material. Stress-rupture shear tests of single-spot lap joints in 0.4-mm (0.015-in.) thick sheet showed that these welds were as strong as the parent material. Similar results were obtained in tensile-shear tests at room temperature and 1100 C and in fatigue tests. Conventional fusion spot welds in commercial sheet were unsatisfactory because of poor stress-rupture shear properties resulting from metallurgical damage to the parent material.

Status of the irradiation test vehicle for testing fusion materials in the Advanced Test Reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tsai, H.; Gomes, I.C.; Smith, D.L.

1998-09-01

The design of the irradiation test vehicle (ITV) for the Advanced Test Reactor (ATR) has been completed. The main application for the ITV is irradiation testing of candidate fusion structural materials, including vanadium-base alloys, silicon carbide composites, and low-activation steels. Construction of the vehicle is underway at the Lockheed Martin Idaho Technology Company (LMITCO). Dummy test trains are being built for system checkout and fine-tuning. Reactor insertion of the ITV with the dummy test trains is scheduled for fall 1998. Barring unexpected difficulties, the ITV will be available for experiments in early 1999.

Nuclear energy.

PubMed

Grandin, Karl; Jagers, Peter; Kullander, Sven

2010-01-01

Nuclear energy can play a role in carbon free production of electrical energy, thus making it interesting for tomorrow's energy mix. However, several issues have to be addressed. In fission technology, the design of so-called fourth generation reactors show great promise, in particular in addressing materials efficiency and safety issues. If successfully developed, such reactors may have an important and sustainable part in future energy production. Working fusion reactors may be even more materials efficient and environmental friendly, but also need more development and research. The roadmap for development of fourth generation fission and fusion reactors, therefore, asks for attention and research in these fields must be strengthened.

Using LGI experiments to achieve better understanding of pedestal-edge coupling in NSTX-U

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Zhehui

2015-02-23

PowerPoint presentation. Latest advances in granule or dust injection technologies, fast and high-resolution imaging, together with micro-/nano-structured material fabrication, provide new opportunities to examine plasma-material interaction (PMI) in magnetic fusion environment. Some of our previous work in these areas is summarized. The upcoming LGI experiments in NSTX-U will shed new light on granular matter transport in the pedestal-edge region. In addition to particle control, these results can also be used for code validation and achieving better understanding of pedestal-edge coupling in fusion plasmas in both NSTX-U and others.

Hendra virus fusion protein transmembrane domain contributes to pre-fusion protein stability

PubMed Central

Webb, Stacy; Nagy, Tamas; Moseley, Hunter; Fried, Michael; Dutch, Rebecca

2017-01-01

Enveloped viruses utilize fusion (F) proteins studding the surface of the virus to facilitate membrane fusion with a target cell membrane. Fusion of the viral envelope with a cellular membrane is required for release of viral genomic material, so the virus can ultimately reproduce and spread. To drive fusion, the F protein undergoes an irreversible conformational change, transitioning from a metastable pre-fusion conformation to a more thermodynamically stable post-fusion structure. Understanding the elements that control stability of the pre-fusion state and triggering to the post-fusion conformation is important for understanding F protein function. Mutations in F protein transmembrane (TM) domains implicated the TM domain in the fusion process, but the structural and molecular details in fusion remain unclear. Previously, analytical ultracentrifugation was utilized to demonstrate that isolated TM domains of Hendra virus F protein associate in a monomer-trimer equilibrium (Smith, E. C., Smith, S. E., Carter, J. R., Webb, S. R., Gibson, K. M., Hellman, L. M., Fried, M. G., and Dutch, R. E. (2013) J. Biol. Chem. 288, 35726–35735). To determine factors driving this association, 140 paramyxovirus F protein TM domain sequences were analyzed. A heptad repeat of β-branched residues was found, and analysis of the Hendra virus F TM domain revealed a heptad repeat leucine-isoleucine zipper motif (LIZ). Replacement of the LIZ with alanine resulted in dramatically reduced TM-TM association. Mutation of the LIZ in the whole protein resulted in decreased protein stability, including pre-fusion conformation stability. Together, our data suggest that the heptad repeat LIZ contributed to TM-TM association and is important for F protein function and pre-fusion stability. PMID:28213515

Hendra virus fusion protein transmembrane domain contributes to pre-fusion protein stability.

PubMed

Webb, Stacy; Nagy, Tamas; Moseley, Hunter; Fried, Michael; Dutch, Rebecca

2017-04-07

Enveloped viruses utilize fusion (F) proteins studding the surface of the virus to facilitate membrane fusion with a target cell membrane. Fusion of the viral envelope with a cellular membrane is required for release of viral genomic material, so the virus can ultimately reproduce and spread. To drive fusion, the F protein undergoes an irreversible conformational change, transitioning from a metastable pre-fusion conformation to a more thermodynamically stable post-fusion structure. Understanding the elements that control stability of the pre-fusion state and triggering to the post-fusion conformation is important for understanding F protein function. Mutations in F protein transmembrane (TM) domains implicated the TM domain in the fusion process, but the structural and molecular details in fusion remain unclear. Previously, analytical ultracentrifugation was utilized to demonstrate that isolated TM domains of Hendra virus F protein associate in a monomer-trimer equilibrium (Smith, E. C., Smith, S. E., Carter, J. R., Webb, S. R., Gibson, K. M., Hellman, L. M., Fried, M. G., and Dutch, R. E. (2013) J. Biol. Chem. 288, 35726-35735). To determine factors driving this association, 140 paramyxovirus F protein TM domain sequences were analyzed. A heptad repeat of β-branched residues was found, and analysis of the Hendra virus F TM domain revealed a heptad repeat leucine-isoleucine zipper motif (LIZ). Replacement of the LIZ with alanine resulted in dramatically reduced TM-TM association. Mutation of the LIZ in the whole protein resulted in decreased protein stability, including pre-fusion conformation stability. Together, our data suggest that the heptad repeat LIZ contributed to TM-TM association and is important for F protein function and pre-fusion stability. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Defense Small Business Innovation Research Program (SBIR) Abstracts of Phase 1 Awards 1983.

DTIC Science & Technology

1984-04-06

STRATEGY, THE INTERPLAY BETWEEN ELECTROMAGNETIC EMISSION CON- TROL AND FLEET OPERATION. THE TECHNICAL APPROACH IS BASED ON AN ANALYSIS OF EMCON...THEM AND A BOTTOM UP APPROACH . THE REQUIREMENTS AND ARCHITECTURAL ASPECTS WILL BE EXPLORED FROM THE MORE ENCOMPASSING PERSPECTIVE OF THE TOTAL...AN AI APPROACH TO INFORMATION FUSION INCLUDING KNOW- LEDGE ORGANIZATION, HYPOTHESIS REPRESENTATIVES, DOMAIN KNOWLEDGE RE- PRESENTATION, HYPOTHESIS

Igniting the Light Elements: The Los Alamos Thermonuclear Weapon Project, 1942-1952

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fitzpatrick, Anne C.

1999-07-01

The American system of nuclear weapons research and development was conceived and developed not as a result of technological determinism, but by a number of individual architects who promoted the growth of this large technologically-based complex. While some of the technological artifacts of this system, such as the fission weapons used in World War II, have been the subject of many historical studies, their technical successors--fusion (or hydrogen) devices--are representative of the largely unstudied highly secret realms of nuclear weapons science and engineering. In the postwar period a small number of Los Alamos Scientific Laboratory's staff and affiliates were responsiblemore » for theoretical work on fusion weapons, yet the program was subject to both the provisions and constraints of the US Atomic Energy Commission, of which Los Alamos was a part. The Commission leadership's struggle to establish a mission for its network of laboratories, least of all to keep them operating, affected Los Alamos's leaders' decisions as to the course of weapons design and development projects. Adapting Thomas P. Hughes's ''large technological systems'' thesis, I focus on the technical, social, political, and human problems that nuclear weapons scientists faced while pursuing the thermonuclear project, demonstrating why the early American thermonuclear bomb project was an immensely complicated scientific and technological undertaking. I concentrate mainly on Los Alamos Scientific Laboratory's Theoretical, or T, Division, and its members' attempts to complete an accurate mathematical treatment of the ''Super''--the most difficult problem in physics in the postwar period--and other fusion weapon theories. Although tackling a theoretical problem, theoreticians had to address technical and engineering issues as well. I demonstrate the relative value and importance of H-bomb research over time in the postwar era to scientific, politician, and military participants in this project. I analyze how and when participants in the H-bomb project recognized both blatant and subtle problems facing the project, how scientists solved them, and the relationship this process had to official nuclear weapons policies. Consequently, I show how the practice of nuclear weapons science in the postwar period became an extremely complex, technologically-based endeavor.« less

Targeted resequencing reveals ALK fusions in non-small cell lung carcinomas detected by FISH, immunohistochemistry, and real-time RT-PCR: a comparison of four methods.

PubMed

Tuononen, Katja; Sarhadi, Virinder Kaur; Wirtanen, Aino; Rönty, Mikko; Salmenkivi, Kaisa; Knuuttila, Aija; Remes, Satu; Telaranta-Keerie, Aino I; Bloor, Stuart; Ellonen, Pekka; Knuutila, Sakari

2013-01-01

Anaplastic lymphoma receptor tyrosine kinase (ALK) gene rearrangements occur in a subgroup of non-small cell lung carcinomas (NSCLCs). The identification of these rearrangements is important for guiding treatment decisions. The aim of our study was to screen ALK gene fusions in NSCLCs and to compare the results detected by targeted resequencing with results detected by commonly used methods, including fluorescence in situ hybridization (FISH), immunohistochemistry (IHC), and real-time reverse transcription-PCR (RT-PCR). Furthermore, we aimed to ascertain the potential of targeted resequencing in detection of ALK-rearranged lung carcinomas. We assessed ALK fusion status for 95 formalin-fixed paraffin-embedded tumor tissue specimens from 87 patients with NSCLC by FISH and real-time RT-PCR, for 57 specimens from 56 patients by targeted resequencing, and for 14 specimens from 14 patients by IHC. All methods were performed successfully on formalin-fixed paraffin-embedded tumor tissue material. We detected ALK fusion in 5.7% (5 out of 87) of patients examined. The results obtained from resequencing correlated significantly with those from FISH, real-time RT-PCR, and IHC. Targeted resequencing proved to be a promising method for ALK gene fusion detection in NSCLC. Means to reduce the material and turnaround time required for analysis are, however, needed.

High-temperature molten salt thermal energy storage systems for solar applications

NASA Technical Reports Server (NTRS)

Petri, R. J.; Claar, T. D.; Ong, E.

1983-01-01

Experimental results of compatibility screening studies of 100 salt/containment/thermal conductivity enhancement (TCE) combinations for the high temperature solar thermal application range of 704 deg to 871 C (1300 to 1600 F) are presented. Nine candidate containment/HX alloy materials and two TCE materials were tested with six candidate solar thermal alkali and alkaline earth carbonate storage salts (both reagent and technical grade of each). Compatibility tests were conducted with salt encapsulated in approx. 6.0 inch x 1 inch welded containers of test material from 300 to 3000 hours. Compatibility evaluations were end application oriented, considering the potential 30 year lifetime requirement of solar thermal power plant components. Analyses were based on depth and nature of salt side corrosion of materials, containment alloy thermal aging effects, weld integrity in salt environment, air side containment oxidation, and chemical and physical analyses of the salt. A need for more reliable, and in some cases first time determined thermophysical and transport property data was also identified for molten carbonates in the 704 to 871 C temperature range. In particular, accurate melting point (mp) measurements were performed for Li2CO3 and Na2CO3 while melting point, heat of fusion, and specific heat determinations were conducted on 81.3 weight percent Na2CO3-18.7 weight percent K2CO3 and 52.2 weight percent BaCO3-47.8 weight percent Na2CO3 to support future TES system design and ultimate scale up of solar thermal energy storage (TES) subsystems.

Present status of liquid metal research for a fusion reactor

NASA Astrophysics Data System (ADS)

Tabarés, Francisco L.

2016-01-01

Although the use of solid materials as targets of divertor plasmas in magnetic fusion research is accepted as the standard solution for the very challenging issue of power and particle handling in a fusion reactor, a generalized feeling that the present options chosen for ITER will not represent the best choice for a reactor is growing up. The problems found for tungsten, the present selection for the divertor target of ITER, in laboratory tests and in hot plasma fusion devices suggest so. Even in the absence of the strong neutron irradiation expected in a reactor, issues like surface melting, droplet ejection, surface cracking, dust generation, etc., call for alternative solutions in a long pulse, high efficient fusion energy-producing continuous machine. Fortunately enough, decades of research on plasma facing materials based on liquid metals (LMs) have produced a wealth of appealing ideas that could find practical application in the route to the realization of a commercial fusion power plant. The options presently available, although in a different degree of maturity, range from full coverage of the inner wall of the device with liquid metals, so that power and particle exhaust together with neutron shielding could be provided, to more conservative combinations of liquid metal films and conventional solid targets basically representing a sort of high performance, evaporative coating for the alleviation of the surface degradation issues found so far. In this work, an updated review of worldwide activities on LM research is presented, together with some open issues still remaining and some proposals based on simple physical considerations leading to the optimization of the most conservative alternatives.

Research and Application of Autodesk Fusion360 in Industrial Design

NASA Astrophysics Data System (ADS)

Song, P. P.; Qi, Y. M.; Cai, D. C.

2018-05-01

In 2016, Fusion 360, a productintroduced byAutodesk and integrating industrial design, structural design, mechanical simulation, and CAM, turns out a design platform supportingcollaboration and sharing both cross-platform and via the cloud. In previous products, design and manufacturing use to be isolated. In the course of design, research and development, the communication between designers and engineers used to go on through different software products, tool commands, and even industry terms. Moreover, difficulty also lies with the communication between design thoughts and machining strategies. Naturally, a difficult product design and R & D process would trigger a noticeable gap between the design model and the actual product. A complete product development process tends to cover several major areas, such as industrial design, mechanical design, rendering and animation, computer aided emulation (CAE), and computer aided manufacturing (CAM). Fusion 360, a perfect design solving the technical problems of cross-platform data exchange, realizes the effective control of cross-regional collaboration and presents an overview of collaboration and breaks the barriers between art and manufacturing, andblocks between design and processing. The “Eco-development of Fusion360 Industrial Chain” is both a significant means to and an inevitable trend forthe manufacturers and industrial designers to carry out innovation in China.

A new method for fusion, denoising and enhancement of x-ray images retrieved from Talbot-Lau grating interferometry.

PubMed

Scholkmann, Felix; Revol, Vincent; Kaufmann, Rolf; Baronowski, Heidrun; Kottler, Christian

2014-03-21

This paper introduces a new image denoising, fusion and enhancement framework for combining and optimal visualization of x-ray attenuation contrast (AC), differential phase contrast (DPC) and dark-field contrast (DFC) images retrieved from x-ray Talbot-Lau grating interferometry. The new image fusion framework comprises three steps: (i) denoising each input image (AC, DPC and DFC) through adaptive Wiener filtering, (ii) performing a two-step image fusion process based on the shift-invariant wavelet transform, i.e. first fusing the AC with the DPC image and then fusing the resulting image with the DFC image, and finally (iii) enhancing the fused image to obtain a final image using adaptive histogram equalization, adaptive sharpening and contrast optimization. Application examples are presented for two biological objects (a human tooth and a cherry) and the proposed method is compared to two recently published AC/DPC/DFC image processing techniques. In conclusion, the new framework for the processing of AC, DPC and DFC allows the most relevant features of all three images to be combined in one image while reducing the noise and enhancing adaptively the relevant image features. The newly developed framework may be used in technical and medical applications.

System and method for producing metallic iron

DOEpatents

Bleifuss, Rodney L; Englund, David J; Iwasaki, Iwao; Fosnacht, Donald R; Brandon, Mark M; True, Bradford G

2013-09-17

A hearth furnace for producing metallic iron material has a furnace housing having a drying/preheat zone, a conversion zone, a fusion zone, and optionally a cooling zone, the conversion zone is between the drying/preheat zone and the fusion zone. A moving hearth is positioned within the furnace housing. A hood or separation barrier within at least a portion of the conversion zone, fusion zone or both separates the fusion zone into an upper region and a lower region with the lower region adjacent the hearth and the upper region adjacent the lower region and spaced from the hearth. An injector introduces a gaseous reductant into the lower region adjacent the hearth. A combustion region may be formed above the hood or separation barrier.

Proposal for a possible use of fusion power for hydrogen production within this century

NASA Astrophysics Data System (ADS)

Seifritz, W.

Consideration is given to the possibility of building a commercial fusion power reactor before the turn of the century. The main element incorporated by the proposed system is the PACER project powerplant, which employs the explosive deuterium-deuterium (D-D) fusion process. Because all required technology already exists, PACER is believed to represent the quickest way to harness fusion on a large scale. It is argued that such reactors, scattered throughout the world on a series of 'energy parks', will meet a 30 TW global energy demand after the depletion of fossil fuel resources. Consideration is also given to both the breeding of fissile materials and the electrolytic production of hydrogen; a by-product of which would be deuterium fuel.

Ventral cervical fusion at multiple levels using free vascularized double-islanded fibula - a technical report and review of the relevant literature.

PubMed

Krishnan, Kartik G; Müller, Adolf

2002-04-01

Reconstruction of the cervical spine using free vascularized bone flaps has been described in the literature. The reports involve either one level or, when multiple levels, they describe en bloc resection and reconstruction. Stabilization of different levels with a preserved intermediate segment with a single vascularized flap has not been described. We report on the case of a 55-year-old man, who had been operated several times using conventional techniques for cervical myelopathy and instability, who presented to us with severe neck pain. Diagnostic procedures showed pseudarthrosis of C3/4 and stress-overload of the C3/4 and C5/6 segments. The C4/5 fusion was adequately rigid, but avascular. We performed anterior cervical fusion at the C3/4 and C5/6 levels with a vascularized fibula flap modified as a double island. The rigidly fused C4/5 block was preserved and vascularized with the periosteum bridging the two fibular islands. The method and technique are described in detail. Fusion was adequate. Donor site morbidity was minimal and temporary. The patient is symptom free to date (25 months). The suggested method provides the possibility of vertebral fusion at different levels using a single vascularized flap. The indications for this procedure are (1) repeated failure of conventional methods, (2) established poor bone healing and bone non-union with avascular grafts and (3) a well-fused or preserved intermediate segment. The relevant literature is reviewed.

22 CFR 126.1 - Prohibited exports and sales to certain countries.

Code of Federal Regulations, 2010 CFR

2010-04-01

...-case basis, for supplies of arms and related materials or technical training and assistance intended... Haiti, supplies of arms and related materials for technical training and assistance intended solely for..., defense services or technical data subject to this subchapter may be made to any country referred to in...

10 CFR 4.322 - Written notice, technical assistance, and educational materials.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Written notice, technical assistance, and educational... the Age Discrimination Act of 1975, as Amended Duties of Nrc Recipients § 4.322 Written notice, technical assistance, and educational materials. (a) NRC will provide written notice to each recipient of...

Fusion energy division annual progress report, period ending December 31, 1980

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1981-11-01

The ORNL Program encompasses most aspects of magnetic fusion research including research on two magnetic confinement programs (tokamaks and ELMO bumpy tori); the development of the essential technologies for plasma heating, fueling, superconducting magnets, and materials; the development of diagnostics; the development of atomic physics and radiation effect data bases; the assessment of the environmental impact of magnetic fusion; the physics and engineering of present-generation devices; and the design of future devices. The integration of all of these activities into one program is a major factor in the success of each activity. An excellent example of this integration is themore » extremely successful application of neutral injection heating systems developed at ORNL to tokamaks both in the Fusion Energy Division and at Princeton Plasma Physics Laboratory (PPPL). The goal of the ORNL Fusion Program is to maintain this balance between plasma confinement, technology, and engineering activities.« less

Pre-terrestrial origin of rust in the Nakhla meteorite

NASA Technical Reports Server (NTRS)

Wentworth, Susan J.; Gooding, James L.

1990-01-01

The authors present quantative elemental compositions and summarize textural evidence for the pre-terrestrial origin of rust on the Nakhla meteorite. The material in question is called 'rust' because its phase composition remains unknown. Compelling evidence for the pre-terrestrial origin of the rust is found in rust veins truncated by fusion crust and preserved as faults in sutured igneous crystals. Rust veins that approach the meteorite's fusion crust become discontinuous and exhibit vugs that suggest partial decrepitation; no veins that penetrate the fusion crust have been found. Because the rust probably contains volatile compounds, it is reasonable to expect that heating near the ablation surface (formed during atmospheric entry to Earth) would encourage devolatilization of the rust. Hence, the absence of rust veins in fusion crust and vugs in rust veins near fusion crust clearly imply that the rust existed in the meteorite before atmospheric entry.

Overview of the present progress and activities on the CFETR

NASA Astrophysics Data System (ADS)

Wan, Yuanxi; Li, Jiangang; Liu, Yong; Wang, Xiaolin; Chan, Vincent; Chen, Changan; Duan, Xuru; Fu, Peng; Gao, Xiang; Feng, Kaiming; Liu, Songlin; Song, Yuntao; Weng, Peide; Wan, Baonian; Wan, Farong; Wang, Heyi; Wu, Songtao; Ye, Minyou; Yang, Qingwei; Zheng, Guoyao; Zhuang, Ge; Li, Qiang; CFETR Team

2017-10-01

The China Fusion Engineering Test Reactor (CFETR) is the next device in the roadmap for the realization of fusion energy in China, which aims to bridge the gaps between the fusion experimental reactor ITER and the demonstration reactor (DEMO). CFETR will be operated in two phases. Steady-state operation and self-sufficiency will be the two key issues for Phase I with a modest fusion power of up to 200 MW. Phase II aims for DEMO validation with a fusion power over 1 GW. Advanced H-mode physics, high magnetic fields up to 7 T, high frequency electron cyclotron resonance heating and lower hybrid current drive together with off-axis negative-ion neutral beam injection will be developed for achieving steady-state advanced operation. The recent detailed design, research and development (R&D) activities including integrated modeling of operation scenarios, high field magnet, material, tritium plant, remote handling and future plans are introduced in this paper.

A testbed for architecture and fidelity trade studies in the Bayesian decision-level fusion of ATR products

NASA Astrophysics Data System (ADS)

Erickson, Kyle J.; Ross, Timothy D.

2007-04-01

Decision-level fusion is an appealing extension to automatic/assisted target recognition (ATR) as it is a low-bandwidth technique bolstered by a strong theoretical foundation that requires no modification of the source algorithms. Despite the relative simplicity of decision-level fusion, there are many options for fusion application and fusion algorithm specifications. This paper describes a tool that allows trade studies and optimizations across these many options, by feeding an actual fusion algorithm via models of the system environment. Models and fusion algorithms can be specified and then exercised many times, with accumulated results used to compute performance metrics such as probability of correct identification. Performance differences between the best of the contributing sources and the fused result constitute examples of "gain." The tool, constructed as part of the Fusion for Identifying Targets Experiment (FITE) within the Air Force Research Laboratory (AFRL) Sensors Directorate ATR Thrust, finds its main use in examining the relationships among conditions affecting the target, prior information, fusion algorithm complexity, and fusion gain. ATR as an unsolved problem provides the main challenges to fusion in its high cost and relative scarcity of training data, its variability in application, the inability to produce truly random samples, and its sensitivity to context. This paper summarizes the mathematics underlying decision-level fusion in the ATR domain and describes a MATLAB-based architecture for exploring the trade space thus defined. Specific dimensions within this trade space are delineated, providing the raw material necessary to define experiments suitable for multi-look and multi-sensor ATR systems.

First wall for polarized fusion reactors

DOEpatents

Greenside, Henry S.; Budny, Robert V.; Post, Jr., Douglass E.

1988-01-01

Depolarization mechanisms arising from the recycling of the polarized fuel at the limiter and the first-wall of a fusion reactor are greater than those mechanisms in the plasma. Rapid depolarization of the plasma is prevented by providing a first-wall or first-wall coating formed of a low-Z, non-metallic material having a depolarization rate greater than 1 sec.sup.-1.

Advanced manufacturing—A transformative enabling capability for fusion

DOE PAGES

Nygren, Richard E.; Dehoff, Ryan R.; Youchison, Dennis L.; ...

2018-05-24

Additive Manufacturing (AM) can create novel and complex engineered material structures. Features such as controlled porosity, micro-fibers and/or nano-particles, transitions in materials and integral robust coatings can be important in developing solutions for fusion subcomponents. A realistic understanding of this capability would be particularly valuable in identifying development paths. Major concerns for using AM processes with lasers or electron beams that melt powder to make refractory parts are the power required and residual stresses arising in fabrication. A related issue is the required combination of lasers or e-beams to continue heating of deposited material (to reduce stresses) and to depositmore » new material at a reasonable built rate while providing adequate surface finish and resolution for meso-scale features. In conclusion, Some Direct Write processes that can make suitable preforms and be cured to an acceptable density may offer another approach for PFCs.« less

Advanced manufacturing—A transformative enabling capability for fusion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nygren, Richard E.; Dehoff, Ryan R.; Youchison, Dennis L.

Additive Manufacturing (AM) can create novel and complex engineered material structures. Features such as controlled porosity, micro-fibers and/or nano-particles, transitions in materials and integral robust coatings can be important in developing solutions for fusion subcomponents. A realistic understanding of this capability would be particularly valuable in identifying development paths. Major concerns for using AM processes with lasers or electron beams that melt powder to make refractory parts are the power required and residual stresses arising in fabrication. A related issue is the required combination of lasers or e-beams to continue heating of deposited material (to reduce stresses) and to depositmore » new material at a reasonable built rate while providing adequate surface finish and resolution for meso-scale features. In conclusion, Some Direct Write processes that can make suitable preforms and be cured to an acceptable density may offer another approach for PFCs.« less

Molecular dynamics simulations of interactions between hydrogen and fusion-relevant materials

NASA Astrophysics Data System (ADS)

de Rooij, E. D.

2010-02-01

In a thermonuclear reactor fusion between hydrogen isotopes takes place, producing helium and energy. The so-called divertor is the part of the fusion reactor vessel where the plasma is neutralized in order to exhaust the helium. The surface plates of the divertor are subjected to high heat loads and high fluxes of energetic hydrogen and helium. In the next generation fusion device - the tokamak ITER - the expected conditions at the plates are particle fluxes exceeding 1e24 per second and square metre, particle energies ranging from 1 to 100 eV and an average heat load of 10 MW per square metre. Two materials have been identified as candidates for the ITER divertor plates: carbon and tungsten. Since there are currently no fusion devices that can create these harsh conditions, it is unknown how the materials will behave in terms of erosion and hydrogen retention. To gain more insight in the physical processes under these conditions molecular dynamics simulations have been conducted. Since diamond has been proposed as possible plasma facing material, we have studied erosion and hydrogen retention in diamond and amorphous hydrogenated carbon (a-C:H). As in experiments, diamond shows a lower erosion yield than a-C:H, however the hydrogen retention in diamond is much larger than in a-C:H and also hardly depending on the substrate temperature. This implies that simple heating of the surface is not sufficient to retrieve the hydrogen from diamond material, whereas a-C:H readily releases the retained hydrogen. So, in spite of the higher erosion yield carbon material other than diamond seems more suitable. Experiments suggest that the erosion yield of carbon material decreases with increasing flux. This was studied in our simulations. The results show no flux dependency, suggesting that the observed reduction is not a material property but is caused by external factors as, for example, redeposition of the erosion products. Our study of the redeposition showed that the sticking probability of small hydrocarbons is highest on material previously subjected to the highest hydrogen flux. This result suggests that redeposition is more effective under high than under low hydrogen fluxes, partly explaining the experimentally observed reduction in the carbon erosion yield. Lastly, we studied amorphous tungsten carbide. Amorphous material with three different carbon percentages (15, 50 and 95%) was subjected to deuterium bombardment and the resulting erosion and deuterium retention was analysed. The 95% carbon sample behaves like doped carbon, the carbon erosion yield is reduced and no tungsten is eroded. Segregation of the materials was observed, resulting in an accumulation of tungsten at the surface. The hydrogen retention was similar to a-C:H. The 15% carbon sample showed no significant erosion or retention. The most interesting was the 50% sample. Here deuterium bubbles formed that burst open after sufficiently long bombardment, thereby removing both carbon and tungsten from the surface. In the context of ITER our MD simulations suggest that tungsten is the better suited material since both the erosion and the hydrogen retention are significantly lower than for carbon.

Health physics measurement of Princeton Tokamaks, 1977-1987.

PubMed

Stencel, J R; Gilbert, J D; Couch, J G; Griesbach, O A; Fennimore, J J; Greco, J M

1989-06-01

The Princeton Plasma Physics Laboratory (PPPL) began fusion experiments in 1951. In the early years, the major health physics concerns were associated with x radiation produced by energetic electrons in the plasma. Within the past year, neutron and 3H production from 2H-2H (represented hereafter as D-D) reactions has increased significantly on the larger fusion devices. Tritium retention noted in graphite tiles underscores the significance of material selection in present and future 3H-fueled fusion devices. This paper reports on operational health physics radiation measurements made on various PPPL machines over the past 10 y.

Development of tungsten armor and bonding to copper for plasma-interactive components

NASA Astrophysics Data System (ADS)

Smid, I.; Akiba, M.; Vieider, G.; Plöchl, L.

1998-10-01

For the highest sputtering threshold of all possible candidates, tungsten will be the most likely armor material in highly loaded plasma-interactive components of commercially relevant fusion reactors. The development of new materials, as well as joining and coating techniques are needed to find the best balance in plasma compatibility, lifetime, reliability, neutron irradiation resistance, and safety. Further important issues for selection are availability, costs of machining and production, etc. Tungsten doped with lanthanum oxide is a commercially available W grade for electrodes, designed for low electron work function, higher recrystallization temperature, reduced secondary grain growth, and machinability at relatively low costs. W-Re and related tungsten base alloys are preferred for application at high temperatures, when high strength, high thermal shock and recrystallization resistance are required. Due to the high costs and limited global availability of Re, however, the amount of such alloys in a commercial reactor should be kept low. Newly measured material properties up to high temperatures are presented for lanthanated and W-Re alloys, and the impact on fusion application is discussed. Recently developed coatings of chemical vapor deposited tungsten (CVD-W) on copper substrates have proven to be resistant to repeated thermal and shock loading. Layers of more than 5 mm, as required for the International Thermonuclear Experimental Reactor (ITER), became available. Vacuum plasma sprayed tungsten (VPS-W) in particular is attractive for its lower costs, and the potential of in situ repair. However, the advantage of sacrificial plasma-interactive tungsten coatings in long-term fusion devices has yet to be demonstrated. A durable and reliable joining of bulk tungsten to copper is needed to achieve an acceptable component lifetime in a fusion environment. The material properties of the copper alloys proposed for ITER, and their impact on the quality of bonding to tungsten is discussed. Future materials R&D should concern issues such as plasma compatibility, and above all neutron irradiation damage of promising tungsten-copper joints.

The effect of low energy helium ion irradiation on tungsten-tantalum (W-Ta) alloys under fusion relevant conditions

NASA Astrophysics Data System (ADS)

Gonderman, S.; Tripathi, J. K.; Novakowski, T. J.; Sizyuk, T.; Hassanein, A.

2017-08-01

Currently, tungsten remains the best candidate for plasma-facing components (PFCs) for future fusion devices because of its high melting point, low erosion, and strong mechanical properties. However, continued investigation has shown tungsten to undergo severe morphology changes under fusion-like conditions. These results motivate the study of innovative PFC materials which are resistant to surface morphology evolution. The goal of this work is to examine tungsten-tantalum (W-Ta) alloys, a potential PFC material, and their response to low energy helium ion irradiation. Specifically, W-Ta samples are exposed to 100 eV helium irradiations with a flux of 1.15 × 1021 ions m-2 s-1, at 873 K, 1023 K, and 1173 K for 1 h duration. Scanning electron microscopy (SEM) reveals significant changes in surface deterioration due to helium ion irradiation as a function of both temperature and tantalum concentration in W-Ta samples. X-Ray Diffraction (XRD) studies show a slight lattice parameter expansion in W-Ta alloy samples compared to pure W samples. The observed lattice parameter expansion in W-Ta alloy samples (proportional to increasing Ta wt.% concentrations) reflect significant differences observed in the evolution of surface morphology, i.e., fuzz development processes for both increasing Ta wt.% concentration and target temperature. These results suggest a correlation between the observed morphology differences and the induced crystal structure change caused by the presence of tantalum. Shifts in the XRD peaks before and after 100 eV helium irradiation with a flux of 1.15 × 1021 ions m-2 s-1, 1023 K, for 1 h showed a significant difference in the magnitude of the shift. This has suggested a possible link between the atomic spacing of the material and the accumulated damage. Ongoing research is needed on W-Ta alloys and other innovative materials for their application as irradiation resistant materials in future fusion or irradiation environments.

Classification of weld defect based on information fusion technology for radiographic testing system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, Hongquan; Liang, Zeming, E-mail: heavenlzm@126.com; Gao, Jianmin

Improving the efficiency and accuracy of weld defect classification is an important technical problem in developing the radiographic testing system. This paper proposes a novel weld defect classification method based on information fusion technology, Dempster–Shafer evidence theory. First, to characterize weld defects and improve the accuracy of their classification, 11 weld defect features were defined based on the sub-pixel level edges of radiographic images, four of which are presented for the first time in this paper. Second, we applied information fusion technology to combine different features for weld defect classification, including a mass function defined based on the weld defectmore » feature information and the quartile-method-based calculation of standard weld defect class which is to solve a sample problem involving a limited number of training samples. A steam turbine weld defect classification case study is also presented herein to illustrate our technique. The results show that the proposed method can increase the correct classification rate with limited training samples and address the uncertainties associated with weld defect classification.« less

Classification of weld defect based on information fusion technology for radiographic testing system.

PubMed

Jiang, Hongquan; Liang, Zeming; Gao, Jianmin; Dang, Changying

2016-03-01

Improving the efficiency and accuracy of weld defect classification is an important technical problem in developing the radiographic testing system. This paper proposes a novel weld defect classification method based on information fusion technology, Dempster-Shafer evidence theory. First, to characterize weld defects and improve the accuracy of their classification, 11 weld defect features were defined based on the sub-pixel level edges of radiographic images, four of which are presented for the first time in this paper. Second, we applied information fusion technology to combine different features for weld defect classification, including a mass function defined based on the weld defect feature information and the quartile-method-based calculation of standard weld defect class which is to solve a sample problem involving a limited number of training samples. A steam turbine weld defect classification case study is also presented herein to illustrate our technique. The results show that the proposed method can increase the correct classification rate with limited training samples and address the uncertainties associated with weld defect classification.

Addressing Common Technical challenges in Inertial Confinement Fusion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haynes, Donald A.

2016-09-22

The implosion phase for Inertial Confinement Fusion (ICF) occurs from initiation of the drive until just before stagnation. Evolution of the shell and fusion fuel during the implosion phase is affected by the initial conditions of the target, the drive history. Poor performing implosions are a result of the behavior that occurs during the implosion phase such as low mode asymmetries, mixing of the ablator into the fuel, and the hydrodynamic evolution of initial target features and defects such as the shell mounting hardware. The ultimate results of these effects can only be measured at stagnation. However, studying the implosionmore » phase can be effective for understanding and mitigating these effects and for of ultimately improving the performance of ICF implosions. As the ICF program moves towards the 2020 milestone to “determine the efficacy of ignition”, it will be important to understand the physics that occurs during the implosion phase. This will require both focused and integrated experiments. Focused experiments will provide the understanding and the evidence needed to support any determination concerning the efficacy of ignition.« less

Microstructure characterisation of Ti-6Al-4V from different additive manufacturing processes

NASA Astrophysics Data System (ADS)

Neikter, M.; Åkerfeldt, P.; Pederson, R.; Antti, M.-L.

2017-10-01

The focus of this work has been microstructure characterisation of Ti-6Al-4V manufactured by five different additive manufacturing (AM) processes. The microstructure features being characterised are the prior β size, grain boundary α and α lath thickness. It was found that material manufactured with powder bed fusion processes has smaller prior β grains than the material from directed energy deposition processes. The AM processes with fast cooling rate render in thinner α laths and also thinner, and in some cases discontinuous, grain boundary α. Furthermore, it has been observed that material manufactured with the directed energy deposition processes has parallel bands, except for one condition when the parameters were changed, while the powder bed fusion processes do not have any parallel bands.

Development of High-Z Materials with Improved Toughness for High Heat Flux Components

NASA Astrophysics Data System (ADS)

Kurishita, Hiroaki; Kitsunai, Yuji; Kuwabara, Tetsuya; Hasegawa, Masayuki; Hiraoka, Yutaka; Takida, Tomohiro; Igarashi, Tadashi

Tungsten is superior to other materials in physical and mechanical properties for use as high heat flux components in future fusion reactors. The key issue of the metal is to improve the low temperature embrittlement, the recrystallization embrittlement and the irradiation embrittlement. An alloy design and microstructure control for achieving simultaneous and significant improvements in those embrittlements are described and are applied to tungsten and molybdenum which has quite similar properties as tungsten. The result of the application is presented for each of the embrittlement, with considerable success. Emphasis is placed on the occurrence of RIDU (Radiation Induced Ductilization) because RIDU is expected to provide the scenario to overcome severe irradiation embrittlement that is the most crucial problem for structure materials exposed in fusion environment.

Development of fusogenic glass surfaces that impart spatiotemporal control over macrophage fusion: Direct visualization of multinucleated giant cell formation

PubMed Central

Faust, James J.; Christenson, Wayne; Doudrick, Kyle; Ros, Robert

2017-01-01

Implantation of synthetic material, including vascular grafts, pacemakers, etc. results in the foreign body reaction and the formation of multinucleated giant cells (MGCs) at the exterior surface of the implant. Despite the long-standing premise that fusion of mononucleated macrophages results in the formation of MGCs, to date, no published study has shown fusion in context with living specimens. This is due to the fact that optical-quality glass, which is required for the majority of live imaging techniques, does not promote macrophage fusion. Consequently, the morphological changes that macrophages undergo during fusion as well as the mechanisms that govern this process remain ill-defined. In this study, we serendipitously identified a highly fusogenic glass surface and discovered that the capacity to promote fusion was due to oleamide contamination. When adsorbed on glass, oleamide and other molecules that contain long-chain hydrocarbons promoted high levels of macrophage fusion. Adhesion, an essential step for macrophage fusion, was apparently mediated by Mac-1 integrin (CD11b/CD18, αMβ2) as determined by single cell force spectroscopy and adhesion assays. Micropatterned glass further increased fusion and enabled a remarkable degree of spatiotemporal control over MGC formation. Using these surfaces, we reveal the kinetics that govern MGC formation in vitro. We anticipate that the spatiotemporal control afforded by these surfaces will expedite studies designed to identify the mechanism(s) of macrophage fusion and MGC formation with implication for the design of novel biomaterials. PMID:28340410

Will fusion be ready to meet the energy challenge for the 21st century?

NASA Astrophysics Data System (ADS)

Bréchet, Yves; Massard, Thierry

2016-05-01

Finite amount of fossil fuel, global warming, increasing demand of energies in emerging countries tend to promote new sources of energies to meet the needs of the coming centuries. Despite their attractiveness, renewable energies will not be sufficient both because of intermittency but also because of the pressure they would put on conventional materials. Thus nuclear energy with both fission and fusion reactors remain the main potential source of clean energy for the coming centuries. France has made a strong commitment to fusion reactor through ITER program. But following and sharing Euratom vision on fusion, France supports the academic program on Inertial Fusion Confinement with direct drive and especially the shock ignition scheme which is heavily studied among the French academic community. LMJ a defense facility for nuclear deterrence is also open to academic community along with a unique PW class laser PETAL. Research on fusion at LMJ-PETAL is one of the designated topics for experiments on the facility. Pairing with other smaller European facilities such as Orion, PALS or LULI2000, LMJ-PETAL will bring new and exciting results and contribution in fusion science in the coming years.

Material Issues of Blanket Systems for Fusion Reactors - Compatibility with Cooling Water -

NASA Astrophysics Data System (ADS)

Miwa, Yukio; Tsukada, Takashi; Jitsukawa, Shiro

Environmental assisted cracking (EAC) is one of the material issues for the reactor core components of light water power reactors(LWRs). Much experience and knowledge have been obtained about the EAC in the LWR field. They will be useful to prevent the EAC of water-cooled blanket systems of fusion reactors. For the austenitic stainless steels and the reduced-activation ferritic/martensitic steels, they clarifies that the EAC in a water-cooled blanket does not seem to be acritical issue. However, some uncertainties about influences on water temperatures, water chemistries and stress conditions may affect on the EAC. Considerations and further investigations elucidating the uncertainties are discussed.

Corrosion properties of powder bed fusion additively manufactured 17-4 PH stainless steel

DOE PAGES

Schaller, Rebecca; Taylor, Jason; Rodelas, Jeffrey; ...

2017-02-20

The corrosion susceptibility of a laser powder bed fusion (LPBF) additively manufactured alloy, UNS S17400 (17-4 PH), was explored compared to conventional wrought material. Microstructural characteristics were characterized and related to corrosion behavior in quiescent, aqueous 0.6 M NaCl solutions. Electrochemical measurements demonstrated that the LPBF 17-4 PH alloy exhibited a reduced passivity range and active corrosion compared to its conventional wrought counterpart. Lastly, a micro-electrochemical cell was employed to further understand the effects of the local scale and attributed the reduced corrosion resistance of the LPBF material to pores with diameters ≥ 50 µm.

Corrosion properties of powder bed fusion additively manufactured 17-4 PH stainless steel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schaller, Rebecca; Taylor, Jason; Rodelas, Jeffrey

The corrosion susceptibility of a laser powder bed fusion (LPBF) additively manufactured alloy, UNS S17400 (17-4 PH), was explored compared to conventional wrought material. Microstructural characteristics were characterized and related to corrosion behavior in quiescent, aqueous 0.6 M NaCl solutions. Electrochemical measurements demonstrated that the LPBF 17-4 PH alloy exhibited a reduced passivity range and active corrosion compared to its conventional wrought counterpart. Lastly, a micro-electrochemical cell was employed to further understand the effects of the local scale and attributed the reduced corrosion resistance of the LPBF material to pores with diameters ≥ 50 µm.

Simulating irradiation hardening in tungsten under fast neutron irradiation including Re production by transmutation

NASA Astrophysics Data System (ADS)

Huang, Chen-Hsi; Gilbert, Mark R.; Marian, Jaime

2018-02-01

Simulations of neutron damage under fusion energy conditions must capture the effects of transmutation, both in terms of accurate chemical inventory buildup as well as the physics of the interactions between transmutation elements and irradiation defect clusters. In this work, we integrate neutronics, primary damage calculations, molecular dynamics results, Re transmutation calculations, and stochastic cluster dynamics simulations to study neutron damage in single-crystal tungsten to mimic divertor materials. To gauge the accuracy and validity of the simulations, we first study the material response under experimental conditions at the JOYO fast reactor in Japan and the High Flux Isotope Reactor at Oak Ridge National Laboratory, for which measurements of cluster densities and hardening levels up to 2 dpa exist. We then provide calculations under expected DEMO fusion conditions. Several key mechanisms involving Re atoms and defect clusters are found to govern the accumulation of irradiation damage in each case. We use established correlations to translate damage accumulation into hardening increases and compare our results to the experimental measurements. We find hardening increases in excess of 5000 MPa in all cases, which casts doubts about the integrity of W-based materials under long-term fusion exposure.

The Challenges of Plasma Material Interactions in Nuclear Fusion Devices and Potential Solutions

DOE PAGES

Rapp, J.

2017-07-12

Plasma Material Interactions in future fusion reactors have been identified as a knowledge gap to be dealt with before any next step device past ITER can be built. The challenges are manifold. They are related to power dissipation so that the heat fluxes to the plasma facing components can be kept at technologically feasible levels; maximization of the lifetime of divertor plasma facing components that allow for steady-state operation in a reactor to reach the neutron fluences required; the tritium inventory (storage) in the plasma facing components, which can lead to potential safety concerns and reduction in the fuel efficiency;more » and it is related to the technology of the plasma facing components itself, which should demonstrate structural integrity under the high temperatures and neutron fluence. This contribution will give an overview and summary of those challenges together with some discussion of potential solutions. New linear plasma devices are needed to investigate the PMI under fusion reactor conditions and test novel plasma facing components. The Material Plasma Exposure eXperiment MPEX will be introduced and a status of the current R&D towards MPEX will be summarized.« less

The Challenges of Plasma Material Interactions in Nuclear Fusion Devices and Potential Solutions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rapp, J.

Plasma Material Interactions in future fusion reactors have been identified as a knowledge gap to be dealt with before any next step device past ITER can be built. The challenges are manifold. They are related to power dissipation so that the heat fluxes to the plasma facing components can be kept at technologically feasible levels; maximization of the lifetime of divertor plasma facing components that allow for steady-state operation in a reactor to reach the neutron fluences required; the tritium inventory (storage) in the plasma facing components, which can lead to potential safety concerns and reduction in the fuel efficiency;more » and it is related to the technology of the plasma facing components itself, which should demonstrate structural integrity under the high temperatures and neutron fluence. This contribution will give an overview and summary of those challenges together with some discussion of potential solutions. New linear plasma devices are needed to investigate the PMI under fusion reactor conditions and test novel plasma facing components. The Material Plasma Exposure eXperiment MPEX will be introduced and a status of the current R&D towards MPEX will be summarized.« less

Control of autonomous ground vehicles: a brief technical review

NASA Astrophysics Data System (ADS)

Babak, Shahian-Jahromi; Hussain, Syed A.; Karakas, Burak; Cetin, Sabri

2017-07-01

This paper presents a brief review of the developments achieved in autonomous vehicle systems technology. A concise history of autonomous driver assistance systems is presented, followed by a review of current state of the art sensor technology used in autonomous vehicles. Standard sensor fusion method that has been recently explored is discussed. Finally, advances in embedded software methodologies that define the logic between sensory information and actuation decisions are reviewed.

U.S.-Russian Civilian Nuclear Cooperation Agreement: Issues for Congress

DTIC Science & Technology

2010-07-09

for nuclear cooperation in 1973 to allow for cooperation in controlled thermonuclear fusion, fast breeder reactors , and fundamental research. The...that a 123 agreement is needed to implement this action plan—for example, full scale technical cooperation on fast reactors and demonstration of...superpowers convened a Joint Coordinating Committee for Civilian Reactor Safety starting in 1988.10 After the fall of the Soviet Union and prior to July

Materials Testing and Quality Control Soils, 3-28. Military Curriculum Materials for Vocational and Technical Education.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus. National Center for Research in Vocational Education.

This instructional package on material testing and quality control of soils has been adapted from military curriculum materials for use in technical and vocational education programs. This short course presents basic information on soils as well as exploration, field identification, and laboratory procedures that will enable students completing…

Special issue containing papers presented at the 12th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems (7-11 September 2011) Special issue containing papers presented at the 12th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems (7-11 September 2011)

NASA Astrophysics Data System (ADS)

Berk, H. L.

2012-09-01

The topic of the behaviour of energetic alpha particles in magnetic fusion confined plasmas is perhaps the ultimate frontier plasma physics issue that needs to be understood in the quest to achieve controlled power from the fusion reaction in magnetically confined plasmas. The partial pressure of alpha particles in a burning plasma will be ~5-10% of the total pressure and under these conditions the alpha particles may be prone to develop instability through Alfvénic interaction. This may lead, even with moderate alpha particle loss, to a burn quench or severe wall damage. Alternatively, benign Alfvénic signals may allow the vital information to control a fusion burn. The significance of this issue has led to extensive international investigations and a biannual meeting that began in Kyiv in 1989, followed by subsequent meetings in Aspenäs (1991), Trieste (1993), Princeton (1995), JET/Abingdon (1997), Naka (1999), Gothenburg (2001), San Diego (2003), Takayama (2005), Kloster Seeon (2007) and Kyiv (2009). The meeting was initially entitled 'Alpha Particles in Fusion Research' and then was changed during the 1997 meeting to 'Energetic Particles in Magnetic Confinement Systems' in appreciation of the need to study the significance of the electron runaway, which can lead to the production of energetic electrons with energies that can even exceed the energy produced by fusion products. This special issue presents some of the mature interesting work that was reported at the 12th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems, which was held in Austin, Texas, USA (7-11 September 2011). This meeting immediately followed a related meeting, the 5th IAEA Technical Meeting on Theory of Plasma Wave Instabilities (5-7 September 2011). The meetings shared one day (7 September 2011) with presentations relevant to both groups. The presentations from most of the participants, as well as some preliminary versions of papers, are available at the websites [1, 2]. To view a presentation or paper, go to the link 'program', view the list or speakers and poster presenters and press 'talk' or 'paper' under the appropriate name. Summaries of the Energetic Particle Conference presentations were given by Kazuo Toi and Boris Breizman. They respectively discussed the experimental and theoretical progress presented at the meeting. Their presentations can be viewed on the 'iaeaep' website [1], by pressing 'Summary-I (or II)' by each of their names. Highlights of this meeting include the tremendous progress that has been achieved in the development of diagnostics that enables the 'viewing' of internal fluctuations and allows comparison with theoretical predictions, as demonstrated, for example, in the talks of P. Lauber and M. Osakabe. The need and development of hardened diagnostics in the severe radiation environment, such as those that will exist in ITER, was discussed in the talks of V. Kiptiley and V.A. Kazakhov. In theoretical studies, much of the effort is focused on nonlinear phenomena. For example, detailed comparison of theory and experiment on D-III-D on the n = 0 geodesic mode was reported in separate papers by R. Nazikian and G. Fu. A large number of theoretical papers were presented on wave chirping including a paper by B.N. Breizman, which notes that continual wave chirping from a single frequency may emanate continuously once marginal stability conditions have been established. Another area of wide interest was the detailed study of alpha orbits in a burning plasma, where losses can come from perturbations from perfect toroidal symmetry arising from finite coil number, magnetic field imperfections introduced by diagnostic or test modules and from instability. An important area of development, covered by M.A. Hole and D.A. Spong, is concerned with the self-consistent treatment of the induced fields that accounts for responses beyond vacuum field perturbations or a pure toroidally symmetric MHD response. In addition, a significant number of studies focused on understanding nonlinear behaviour by means of computer simulation of energetic particle driven instability. An under-represented area of investigation was the study of electron runaway formation during major tokamak disruptions. It was noted in an overview by S. Putvinski that electron energies in the 10-20 MeV range is to be expected during projected major disruptions in ITER and that reliable methods for mitigation of the runaway process needs to be developed. Significant recent work in the field of the disruption induced electron runaway, which was reported by J. Riemann, does not appear in this special issue of Nuclear Fusion as the work had been previously submitted to Physics of Plasmas [3]. Overall it is clear that reliable mitigation of electron runaway is an extremely important topic that is in need of better understanding and solutions. It has been my pleasure to serve as the organizer of the 12th meeting and to serve as a Guest Editor of this issue of Nuclear Fusion. I am sure that the contents of this issue will serve as a valuable research guide to the field of energetic particle behaviour in a burning plasma for many years to come. The site of the next meeting will by Beijing, China in the fall of 2013, which will be organized by Zinghong Lin. References [1] Program 2011 12th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems (Austin, Texas, USA, 7-11 September 2011) http://w3fusion.ph.utexas.edu/ifs/iaeaep/program.html [2] Program 2011 5th IAEA Technical Meeting on Theory of Plasma Wave Instabilities (Austin, Texas, USA, 5-7 September 2011) http://w3fusion.ph.utexas.edu/ifs/iaeapi/program.html [3] Riemann J., Smith H.M. and Helander P. 2012 Phys. Plasmas 19 012507

Plasma source development for fusion-relevant material testing

DOE PAGES

Caughman, John B. O.; Goulding, Richard H.; Biewer, Theodore M.; ...

2017-05-01

Plasma facing materials in the divertor of a magnetic fusion reactor will have to tolerate steady-state plasma heat fluxes in the range of 10 MW/m2 for ~107 sec, in addition to fusion neutron fluences, which can damage the plasma facing materials to high displacements per atom (dpa) of ~50 dpa . Material solutions needed for the plasma facing components are yet to be developed and tested. The Materials Plasma Exposure eXperiment (MPEX) is a newly proposed steady state linear plasma device that is designed to deliver the necessary plasma heat flux to a target for this material testing, including themore » capability to expose a-priori neutron damaged material samples to those plasmas. The requirements of the plasma source needed to deliver this plasma heat flux are being developed on the Proto-MPEX device, which is a linear high-intensity radio frequency (RF) plasma source that combines a high-density helicon plasma generator with electron and ion heating sections. It is being used to study the physics of heating over-dense plasmas in a linear configuration. The helicon plasma is operated at 13.56 MHz with RF power levels up to 120 kW. Microwaves at 28 GHz (~30 kW) are coupled to the electrons in the over-dense helicon plasma via Electron Bernstein Waves (EBW), and ion cyclotron heating at 7-9 MHz (~30 kW) is via a magnetic beach approach. High plasma densities >6x1019/m3 have been produced in deuterium, with electron temperatures that can range from 2 to >10 eV. Operation with on-axis magnetic field strengths between 0.6 and 1.4 T is typical. The plasma heat flux delivered to a target can be > 10 MW/m2, depending on the operating conditions.« less

Micro-engineered first wall tungsten armor for high average power laser fusion energy systems

NASA Astrophysics Data System (ADS)

Sharafat, Shahram; Ghoniem, Nasr M.; Anderson, Michael; Williams, Brian; Blanchard, Jake; Snead, Lance; HAPL Team

2005-12-01

The high average power laser program is developing an inertial fusion energy demonstration power reactor with a solid first wall chamber. The first wall (FW) will be subject to high energy density radiation and high doses of high energy helium implantation. Tungsten has been identified as the candidate material for a FW armor. The fundamental concern is long term thermo-mechanical survivability of the armor against the effects of high temperature pulsed operation and exfoliation due to the retention of implanted helium. Even if a solid tungsten armor coating would survive the high temperature cyclic operation with minimal failure, the high helium implantation and retention would result in unacceptable material loss rates. Micro-engineered materials, such as castellated structures, plasma sprayed nano-porous coatings and refractory foams are suggested as a first wall armor material to address these fundamental concerns. A micro-engineered FW armor would have to be designed with specific geometric features that tolerate high cyclic heating loads and recycle most of the implanted helium without any significant failure. Micro-engineered materials are briefly reviewed. In particular, plasma-sprayed nano-porous tungsten and tungsten foams are assessed for their potential to accommodate inertial fusion specific loads. Tests show that nano-porous plasma spray coatings can be manufactured with high permeability to helium gas, while retaining relatively high thermal conductivities. Tungsten foams where shown to be able to overcome thermo-mechanical loads by cell rotation and deformation. Helium implantation tests have shown, that pulsed implantation and heating releases significant levels of implanted helium. Helium implantation and release from tungsten was modeled using an expanded kinetic rate theory, to include the effects of pulsed implantations and thermal cycles. Although, significant challenges remain micro-engineered materials are shown to constitute potential candidate FW armor materials.

Plasma source development for fusion-relevant material testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Caughman, John B. O.; Goulding, Richard H.; Biewer, Theodore M.

Plasma facing materials in the divertor of a magnetic fusion reactor will have to tolerate steady-state plasma heat fluxes in the range of 10 MW/m2 for ~107 sec, in addition to fusion neutron fluences, which can damage the plasma facing materials to high displacements per atom (dpa) of ~50 dpa . Material solutions needed for the plasma facing components are yet to be developed and tested. The Materials Plasma Exposure eXperiment (MPEX) is a newly proposed steady state linear plasma device that is designed to deliver the necessary plasma heat flux to a target for this material testing, including themore » capability to expose a-priori neutron damaged material samples to those plasmas. The requirements of the plasma source needed to deliver this plasma heat flux are being developed on the Proto-MPEX device, which is a linear high-intensity radio frequency (RF) plasma source that combines a high-density helicon plasma generator with electron and ion heating sections. It is being used to study the physics of heating over-dense plasmas in a linear configuration. The helicon plasma is operated at 13.56 MHz with RF power levels up to 120 kW. Microwaves at 28 GHz (~30 kW) are coupled to the electrons in the over-dense helicon plasma via Electron Bernstein Waves (EBW), and ion cyclotron heating at 7-9 MHz (~30 kW) is via a magnetic beach approach. High plasma densities >6x1019/m3 have been produced in deuterium, with electron temperatures that can range from 2 to >10 eV. Operation with on-axis magnetic field strengths between 0.6 and 1.4 T is typical. The plasma heat flux delivered to a target can be > 10 MW/m2, depending on the operating conditions.« less

Hybrid Biosynthetic Autograft Extender for Use in Posterior Lumbar Interbody Fusion: Safety and Clinical Effectiveness.

PubMed

Chedid, Mokbel K; Tundo, Kelly M; Block, Jon E; Muir, Jeffrey M

2015-01-01

Autologous iliac crest bone graft is the preferred option for spinal fusion, but the morbidity associated with bone harvest and the need for graft augmentation in more demanding cases necessitates combining local bone with bone substitutes. The purpose of this study was to document the clinical effectiveness and safety of a novel hybrid biosynthetic scaffold material consisting of poly(D,L-lactide-co-glycolide) (PLGA, 75:25) combined by lyophilization with unmodified high molecular weight hyaluronic acid (10-12% wt:wt) as an extender for a broad range of spinal fusion procedures. We retrospectively evaluated all patients undergoing single- and multi-level posterior lumbar interbody fusion at an academic medical center over a 3-year period. A total of 108 patients underwent 109 procedures (245 individual vertebral levels). Patient-related outcomes included pain measured on a Visual Analog Scale. Radiographic outcomes were assessed at 6 weeks, 3-6 months, and 1 year postoperatively. Radiographic fusion or progression of fusion was documented in 221 of 236 index levels (93.6%) at a mean (±SD) time to fusion of 10.2+4.1 months. Single and multi-level fusions were not associated with significantly different success rates. Mean pain scores (+SD) for all patients improved from 6.8+2.5 at baseline to 3.6+2.9 at approximately 12 months. Improvements in VAS were greatest in patients undergoing one- or two-level fusion, with patients undergoing multi-level fusion demonstrating lesser but still statistically significant improvements. Overall, stable fusion was observed in 64.8% of vertebral levels; partial fusion was demonstrated in 28.8% of vertebral levels. Only 15 of 236 levels (6.4%) were non-fused at final follow-up.

46 CFR 56.60-1 - Acceptable materials and specifications (replaces 123 and Table 126.1 in ASME B31.1).

Code of Federal Regulations, 2010 CFR

2010-10-01

... Low temperature steel pipe Sec. VIII of the ASME Boiler and Pressure Vessel Code (5). Pipe, welded: A... only, fusion welded steel pipe ASME B31.1 (8). A 358 Electric fusion welded pipe, high temperature... Seamless and welded (no added filler metal) carbon and low alloy tubing for low temperature UCS23, Sec...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barty, Christopher P.J.

Lasers and laser-based sources are now routinely used to control and manipulate nuclear processes, e.g. fusion, fission and resonant nuclear excitation. Two such “nuclear photonics” activities with the potential for profound societal impact will be reviewed in this presentation: the pursuit of laser-driven inertial confinement fusion at the National Ignition Facility and the development of laser-based, mono-energetic gamma-rays for isotope-specific detection, assay and imaging of materials.

Desmoplastic small round cell tumor: evaluation of reverse transcription-polymerase chain reaction and fluorescence in situ hybridization as ancillary molecular diagnostic techniques.

PubMed

Mohamed, Mustafa; Gonzalez, David; Fritchie, Karen J; Swansbury, John; Wren, Dorte; Benson, Charlotte; Jones, Robin L; Fisher, Cyril; Thway, Khin

2017-11-01

Desmoplastic small round cell tumor (DSRCT) is a rare, biologically aggressive soft tissue neoplasm of uncertain differentiation, most often arising in the abdominal and pelvic cavities of adolescents and young adults with a striking male predominance. Histologically, it is characterized by islands of uniform small round cells in prominent desmoplastic stroma, and it has a polyimmunophenotypic profile, typically expressing WT1 and cytokeratin, desmin, and neural/neuroendocrine differentiation markers to varying degrees. Tumors at other sites and with variant morphology are more rarely described. DSRCT is associated with a recurrent t(11;22)(p13;q12) translocation, leading to the characteristic EWSR1-WT1 gene fusion. Fluorescence in situ hybridization (FISH), to detect EWSR1 rearrangement, and reverse transcription-polymerase chain reaction (RT-PCR) to assess for EWSR1-WT1 fusion transcripts are routine diagnostic ancillary tools. We present a large institutional comparative series of FISH and RT-PCR for DSRCT diagnosis. Twenty-six specimens (from 25 patients) histologically diagnosed as DSRCT were assessed for EWSR1 rearrangement and EWSR1-WT1 fusion transcripts. Of these 26 specimens, 24 yielded positive results with either FISH or RT-PCR or both. FISH was performed in 23 samples, with EWSR1 rearrangement seen in 21 (91.3%). RT-PCR was performed in 18 samples, of which 13 (72.2%) harbored EWSR1-WT1 fusion transcripts. The sensitivity of FISH in detecting DSRCT was 91.3%, and that of RT-PCR was 92.8% following omission of four technical failures. Therefore, both methods are comparable in terms of sensitivity. FISH is more sensitive if technical failures for RT-PCR are taken into account, and RT-PCR is more specific in confirming DSRCT. Both methods complement each other by confirming cases that the other method may not. In isolation, FISH is a relatively non-specific diagnostic adjunct due to the number of different neoplasms that can harbor EWSR1 rearrangement, such as Ewing sarcoma. However, in cases with appropriate morphology and a typical pattern of immunostaining, FISH is confirmatory of the diagnosis.

Energy materials coordinating committee (EMACC) Fiscal Year 1982. Annual technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

None, None

1983-03-01

The DOE Energy Materials Coordinating Committee (EMaCC) serves primarily to enhance coordination among the Department's materials programs and to further the effective use of materials expertise within the Department. These functions are accomplished through the exchange of budgetary and planning information among program managers and through technical meetings/ workshops on selected topics involving both DOE and major contractors. In addition, the EMaCC aids in obtaining materials - related inputs for both intra- and interagency compilations. Membership in the EMaCC is open to any Department organizational unit; participants are appointed by Division or Office Directors. The current membership is listed inmore » Table 1. The EMACC reports to the Director of the Office of Energy Research in his capacity as overseer of the technical programs of the Department. This annual technical report is mandated by the EMACC terms of reference. In this report are described 1) EMACC activities for FY 1982; 2) a summary of materials funding in the Department from FY 1978 to the present; and 3) on-going materials programs in the Department.« less

INSTRUCTIONAL MATERIALS CATALOG. (TITLE SUPPLIED).

ERIC Educational Resources Information Center

California State Dept. of Education, Sacramento.

COURSES OF INSTRUCTION, WORKBOOKS, TESTBOOKS, AND EXAMINATIONS ARE LISTED FOR AUTO MECHANICS, CABINET MAKING, CARPENTRY, DRYWALL CONSTRUCTION, RADIO SERVICES, AND 30 OTHER AREAS OF APPRENTICE TRAINING. A SYLLABUS FOR TRAINING PART-TIME TRADE AND TECHNICAL TEACHERS IS INCLUDED WITH TECHNICAL EDUCATION MATERIALS. PRICES ARE LISTED FOR ALL MATERIALS.…

Fusion Ash Separation in the Princeton Field-Reversed Configuration Reactor

NASA Astrophysics Data System (ADS)

Abbate, Joseph; Yeh, Meagan; McGreivy, Nick; Cohen, Samuel

2016-10-01

The Princeton Field-Reversed Configuration (PFRC) concept relies on low-neutron production by D-3He fusion to enable small, safe nuclear-fusion reactors to be built, an approach requiring rapid and efficient extraction of fusion ash and energy produced by D-3He fusion reactions. The ash exhaust stream would contain energetic (0.1-1 MeV) protons, T, 3He, and 4He ions and nearly 1e5 cooler (ca. 100 eV) D ions. The T extracted from the reactor would be a valuable fusion product in that it decays into 3He, which could be used as fuel. If the T were not extracted it would be troublesome because of neutron production by the D-T reaction. This paper discusses methods to separate the various species in a PFRC reactor's exhaust stream. First, we discuss the use of curved magnetic fields to separate the energetic from the cool components. Then we discuss exploiting material properties, specifically reflection, sputtering threshold, and permeability, to allow separation of the hydrogen from the helium isotopes. DOE Contract Number DE-AC02-09CH11466.

Calculations of Excitation Functions of Some Structural Fusion Materials for ( n, t) Reactions up to 50 MeV Energy

NASA Astrophysics Data System (ADS)

Tel, E.; Durgu, C.; Aktı, N. N.; Okuducu, Ş.

2010-06-01

Fusion serves an inexhaustible energy for humankind. Although there have been significant research and development studies on the inertial and magnetic fusion reactor technology, there is still a long way to go to penetrate commercial fusion reactors to the energy market. Tritium self-sufficiency must be maintained for a commercial power plant. For self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. So, the working out the systematics of ( n, t) reaction cross sections is of great importance for the definition of the excitation function character for the given reaction taking place on various nuclei at different energies. In this study, ( n, t) reactions for some structural fusion materials such as 27Al, 51V, 52Cr, 55Mn, and 56Fe have been investigated. The new calculations on the excitation functions of 27Al( n, t)25Mg, 51V( n, t)49Ti, 52Cr( n, t)50V, 55Mn( n, t)53Cr and 56Fe( n, t)54Mn reactions have been carried out up to 50 MeV incident neutron energy. In these calculations, the pre-equilibrium and equilibrium effects have been investigated. The pre-equilibrium calculations involve the new evaluated the geometry dependent hybrid model, hybrid model and the cascade exciton model. Equilibrium effects are calculated according to the Weisskopf-Ewing model. Also in the present work, we have calculated ( n, t) reaction cross-sections by using new evaluated semi-empirical formulas developed by Tel et al. at 14-15 MeV energy. The calculated results are discussed and compared with the experimental data taken from the literature.

LIFE Materials: Overview of Fuels and Structural Materials Issues Volume 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farmer, J

2008-09-08

The National Ignition Facility (NIF) project, a laser-based Inertial Confinement Fusion (ICF) experiment designed to achieve thermonuclear fusion ignition and burn in the laboratory, is under construction at the Lawrence Livermore National Laboratory (LLNL) and will be completed in April of 2009. Experiments designed to accomplish the NIF's goal will commence in late FY2010 utilizing laser energies of 1 to 1.3 MJ. Fusion yields of the order of 10 to 20 MJ are expected soon thereafter. Laser initiated fusion-fission (LIFE) engines have now been designed to produce nuclear power from natural or depleted uranium without isotopic enrichment, and from spentmore » nuclear fuel from light water reactors without chemical separation into weapons-attractive actinide streams. A point-source of high-energy neutrons produced by laser-generated, thermonuclear fusion within a target is used to achieve ultra-deep burn-up of the fertile or fissile fuel in a sub-critical fission blanket. Fertile fuels including depleted uranium (DU), natural uranium (NatU), spent nuclear fuel (SNF), and thorium (Th) can be used. Fissile fuels such as low-enrichment uranium (LEU), excess weapons plutonium (WG-Pu), and excess highly-enriched uranium (HEU) may be used as well. Based upon preliminary analyses, it is believed that LIFE could help meet worldwide electricity needs in a safe and sustainable manner, while drastically shrinking the nation's and world's stockpile of spent nuclear fuel and excess weapons materials. LIFE takes advantage of the significant advances in laser-based inertial confinement fusion that are taking place at the NIF at LLNL where it is expected that thermonuclear ignition will be achieved in the 2010-2011 timeframe. Starting from as little as 300 to 500 MW of fusion power, a single LIFE engine will be able to generate 2000 to 3000 MWt in steady state for periods of years to decades, depending on the nuclear fuel and engine configuration. Because the fission blanket in a fusion-fission hybrid system is subcritical, a LIFE engine can burn any fertile or fissile nuclear material, including un-enriched natural or depleted U and SNF, and can extract a very high percentage of the energy content of its fuel resulting in greatly enhanced energy generation per metric ton of nuclear fuel, as well as nuclear waste forms with vastly reduced concentrations of long-lived actinides. LIFE engines could thus provide the ability to generate vast amounts of electricity while greatly reducing the actinide content of any existing or future nuclear waste and extending the availability of low cost nuclear fuels for several thousand years. LIFE also provides an attractive pathway for burning excess weapons Pu to over 99% FIMA (fission of initial metal atoms) without the need for fabricating or reprocessing mixed oxide fuels (MOX). Because of all of these advantages, LIFE engines offer a pathway toward sustainable and safe nuclear power that significantly mitigates nuclear proliferation concerns and minimizes nuclear waste. An important aspect of a LIFE engine is the fact that there is no need to extract the fission fuel from the fission blanket before it is burned to the desired final level. Except for fuel inspection and maintenance process times, the nuclear fuel is always within the core of the reactor and no weapons-attractive materials are available outside at any point in time. However, an important consideration when discussing proliferation concerns associated with any nuclear fuel cycle is the ease with which reactor fuel can be converted to weapons usable materials, not just when it is extracted as waste, but at any point in the fuel cycle. Although the nuclear fuel remains in the core of the engine until ultra deep actinide burn up is achieved, soon after start up of the engine, once the system breeds up to full power, several tons of fissile material is present in the fission blanket. However, this fissile material is widely dispersed in millions of fuel pebbles, which can be tagged as individual accountable items, and thus made difficult to divert in large quantities. Several topical reports are being prepared on the materials and processes required for the LIFE engine. Specific materials of interest include: (1) Baseline TRISO Fuel (TRISO); (2) Inert Matrix Fuel (IMF) & Other Alternative Solid Fuels; (3) Beryllium (Be) & Molten Lead Blankets (Pb/PbLi); (4) Molten Salt Coolants (FLIBE/FLiNaBe/FLiNaK); (5) Molten Salt Fuels (UF4 + FLIBE/FLiNaBe); (6) Cladding Materials for Fuel & Beryllium; (7) ODS FM Steel (ODS); (8) Solid First Wall (SFW); and (9) Solid-State Tritium Storage (Hydrides).« less

STRESS CORROSION CRACK GROWTH RESPONSE FOR ALLOY 152/52 DISSIMILAR METAL WELDS IN PWR PRIMARY WATER

DOE Office of Scientific and Technical Information (OSTI.GOV)

Toloczko, Mychailo B.; Olszta, Matthew J.; Overman, Nicole R.

2015-08-15

As part of ongoing research into primary water stress corrosion cracking (PWSCC) susceptibility of alloy 690 and its welds, SCC tests have been conducted on alloy 152/52 dissimilar metal (DM) welds with cracks positioned with the goal to assess weld dilution and fusion line effects on SCC susceptibility. No increased crack growth rate was found when evaluating a 20% Cr dilution zone in alloy 152M joined to carbon steel (CS) that had not undergone a post-weld heat treatment (PWHT). However, high SCC crack growth rates were observed when the crack reached the fusion line of that material where it propagatedmore » both on the fusion line and in the heat affected zone (HAZ) of the carbon steel. Crack surface and crack profile examinations of the specimen revealed that cracking in the weld region was transgranular (TG) with weld grain boundaries not aligned with the geometric crack growth plane of the specimen. The application of a typical pressure vessel PWHT on a second set of alloy 152/52 – carbon steel DM weld specimens was found to eliminate the high SCC susceptibility in the fusion line and carbon steel HAZ regions. PWSCC tests were also performed on alloy 152-304SS DM weld specimens. Constant K crack growth rates did not exceed 5x10-9 mm/s in this material with post-test examinations revealing cracking primarily on the fusion line and slightly into the 304SS HAZ.« less

The role and application of ion beam analysis for studies of plasma-facing components in controlled fusion devices

NASA Astrophysics Data System (ADS)

Rubel, Marek; Petersson, Per; Alves, Eduardo; Brezinsek, Sebastijan; Coad, Joseph Paul; Heinola, Kalle; Mayer, Matej; Widdowson, Anna

2016-03-01

First wall materials in controlled fusion devices undergo serious modification by several physical and chemical processes arising from plasma-wall interactions. Detailed information is required for the assessment of material lifetime and accumulation of hydrogen isotopes in wall materials. The intention of this work is to give a concise overview of key issues in the characterization of plasma-facing materials and components in tokamaks, especially in JET with an ITER-Like Wall. IBA techniques play a particularly prominent role here because of their isotope selectivity in the low-Z range (1-10), high sensitivity and combination of several methods in a single run. The role of 3He-based NRA, RBS (standard and micro-size beam) and HIERDA in fuel retention and material migration studies is presented. The use of tracer techniques with rare isotopes (e.g. 15N) or marker layers on wall diagnostic components is described. Special instrumentation, development of equipment to enhance research capabilities and issues in handling of contaminated materials are addressed.

Evaluation of surface, microstructure and phase modifications on various tungsten grades induced by pulsed plasma loading

NASA Astrophysics Data System (ADS)

Vilémová, M.; Pala, Z.; Jäger, A.; Matějíček, J.; Chernyshova, M.; Kowalska-Strzęciwilk, E.; Tonarová, D.; Gribkov, V. A.

2016-03-01

Progress in the field of nuclear fusion requires the development of a new generation of tungsten materials that are expected to meet specific property, lifetime and safety requirements. Pursuing this goal, the new materials must be properly tested in a wide range of conditions including cases where material is brought to the molten stage, such as with large fusion plasma instabilities. In this study, two prospective candidates from the family of dispersion strengthened (DS) tungsten materials, i.e., W-1%Y2O3 and W-2.5%TiC, were subjected to extreme heat loading exerted by the deuterium plasma generator PF6. The study focuses on the interaction of the tungsten matrix with the dispersed particles during material melting. The materials underwent significant changes in microstructure and phase content. Among the most serious was the loss of TiC particles and void formation in W-2.5%TiC and phase change of polymorphic Y2O3 particles in W-1% Y2O3.

Comparison of electron beam and laser beam powder bed fusion additive manufacturing process for high temperature turbine component materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dryepondt, Sebastien N; Pint, Bruce A; Ryan, Daniel

2016-04-01

The evolving 3D printer technology is now at the point where some turbine components could be additive manufactured (AM) for both development and production purposes. However, this will require a significant evaluation program to qualify the process and components to meet current design and quality standards. The goal of the project was to begin characterization of the microstructure and mechanical properties of Nickel Alloy X (Ni-22Cr-18Fe-9Mo) test bars fabricated by powder bed fusion (PBF) AM processes that use either an electron beam (EB) or laser beam (LB) power source. The AM materials produced with the EB and LB processes displayedmore » significant differences in microstructure and resultant mechanical properties. Accordingly, during the design analysis of AM turbine components, the specific mechanical behavior of the material produced with the selected AM process should be considered. Comparison of the mechanical properties of both the EB and LB materials to those of conventionally processed Nickel Alloy X materials indicates the subject AM materials are viable alternatives for manufacture of some turbine components.« less

Characterization of pore and crystal structure of synthesized LiBOB with varying quality of raw materials as electrolyte for lithium-ion battery

NASA Astrophysics Data System (ADS)

Lestariningsih, Titik; Ratri, Christin Rina; Wigayati, Etty Marty; Sabrina, Qolby

2016-02-01

Characterization of pore structure and crystal structure of the LiB(C2O4)2H2O or LIBOB compound has been performed in this study. These recent years, research regarding LiBOB electrolyte salt have been performed using analytical-grade raw materials, therefore this research was aimed to synthesized LiBOB electrolyte salt using the cheaper and abundant technical-grade raw materials. Lithium hydroxide (LiOH), oxalic acid dihydrate (H2C2O4.2H2O), and boric acid (H3BO3) both in technical-grade and analytical-grade quality were used as raw materials for the synthesis of LiBOB. Crystal structure characterization results of synthesized LiBOB from both technical-grade and analytical-grade raw materials have shown the existence of LiBOB and LiBOB hydrate phase with orthorombic structure. These results were also confirmed by FT-IR analysis, which showed the functional groups of LiBOB compounds. SEM analysis results showed that synthesized LiBOB has spherical structure, while commercial LiBOB has cylindrical structure. Synthesized LiBOB has a similar pore size of commercial LiBOB, i.e. 19 nm (mesoporous material). Surface area of synthesized LiBOB from analytical-grade raw materials and technical-grade materials as well as commercial LIBOB were 88.556 m2/g, 41.524 m2/g, and 108.776 m2/g, respectively. EIS analysis results showed that synthesized LiBOB from technical-grade raw materials has lower conductivity than synthesized LiBOB from analytical-grade raw materials.

Effect of fluorides from various restorative materials on remineralization of adjacent tooth: an in vitro study.

PubMed

Baliga, M S; Bhat, S S

2010-01-01

The aim of the study was to evaluate the extent of surface zone remineralization and the effect of fluoride at the inter-proximal adjacent tooth surface, using restorative materials FusionAlloy, Ketac-Fil and Heliomolar. Ninety extracted molar teeth were used of which 45 were placed in artificial caries for 10 weeks. The remaining 45 teeth were filled with the respective restorative materials, mounted with the artificial carious teeth in proximal contact with plaster and placed in artificial saliva for a period of 28 days. Finally, sectioning of artificially carious teeth was done mesio-distally and observed under the optical microscope and scanning electron microscope. Comparison among the groups was done by one-way analysis of variance [ANOVA] and Fischer's F test. Intercomparison between the groups was done by using Dunnett's t-test. Results obtained from transmitted electron microscopic and scanning electron microscopic observations were almost similar with the Ketac-Fil and Heliomolar showing better results in surface zone remineralization compared to FusionAlloy. Also, Ketac-Fil is a good material in releasing fluoride to remineralize enamel when compared to Heliomolar and FusionAlloy. Thus, it can be used mainly in class II cavity restorations of primary and permanent dentitions due to the potential ability of fluoride containing glass ionomer cements and composite resins to remineralize incipient carious lesions on adjacent teeth.

How elements up to 118 were reached and how to go beyond

NASA Astrophysics Data System (ADS)

Düllmann, Christoph E.

2017-11-01

The new superheavy elements with Z=113, 115, 117, and 118 were recently accepted into the periodic table and have been named. Elements with Z≥112 are predominantly produced in 48Ca-induced fusion reactions on actinide targets. This pathway is exhausted at Z=118 due to the lack of target materials with sufficiently high proton number to reach elements with Z≥119. Search experiments for yet heavier elements were performed at GSI Darmstadt and FLNR Dubna. The reactions 50Ti + 249Bk, which leads to Z=119, as well as 64Ni + 238U, 58Fe + 244Pu, 54Cr + 248Cm, and 50Ti + 249Cf, leading to Z=120, have been studied. Despite a total duration of these experiments of more than one year, neither succeeded in the identification of a new element. To obtain improved guidance for better-informed search experiments, nuclear reaction studies appear necessary and have recently started. Also technical advances will be an important pillar to this end. At GSI, work towards a new continuous-wave linear accelerator is ongoing and is briefly described.

A novel method to recover DD fusion proton CR-39 data corrupted by fast ablator ions at OMEGA and the National Ignition Facility

DOE PAGES

Sutcliffe, G. D.; Milanese, L. M.; Orozco, D.; ...

2016-08-05

CR-39 detectors are used routinely in inertial confinement fusion (ICF) experiments as a part of nuclear diagnostics. CR-39 is filtered to stop fast ablator ions which have been accelerated from an ICF implosion due to electric fields caused by laser-plasma interactions. In some experiments, the filtering is insufficient to block these ions and the fusion-product signal tracks are lost in the large background of accelerated ion tracks. A technique for recovering signal in these scenarios has been developed, tested, and implemented successfully. The technique involves removing material from the surface of the CR-39 to a depth beyond the endpoint ofmore » the ablator ion tracks. The technique preserves signal magnitude (yield) as well as structure in radiograph images. The technique is effective when signal particle range is at least 10 μm deeper than the necessary bulk material removal.« less

Low Activation Joining of SiC/SiC Composites for Fusion Applications: Modeling Miniature Torsion Tests with Elastic and Elastic-Plastic Models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Henager, Charles H.; Nguyen, Ba Nghiep; Kurtz, Richard J.

2015-03-01

The use of SiC and SiC-composites in fission or fusion environments requires joining methods for assembling systems. The international fusion community designed miniature torsion specimens for joint testing and irradiation in test reactors with limited irradiation volumes. These torsion specimens fail out-of-plane when joints are strong and when elastic moduli are within a certain range compared to SiC, which causes difficulties in determining shear strengths for joints or for comparing unirradiated and irradiated joints. A finite element damage model was developed that indicates fracture is likely to occur within the joined pieces to cause out-of-plane failures for miniature torsion specimensmore » when a certain modulus and strength ratio between the joint material and the joined material exists. The model was extended to treat elastic-plastic joints such as SiC/epoxy and steel/epoxy joints tested as validation of the specimen design.« less

A novel method to recover DD fusion proton CR-39 data corrupted by fast ablator ions at OMEGA and the National Ignition Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sutcliffe, G. D., E-mail: gdsut@mit.edu; Milanese, L. M.; Orozco, D.

2016-11-15

CR-39 detectors are used routinely in inertial confinement fusion (ICF) experiments as a part of nuclear diagnostics. CR-39 is filtered to stop fast ablator ions which have been accelerated from an ICF implosion due to electric fields caused by laser-plasma interactions. In some experiments, the filtering is insufficient to block these ions and the fusion-product signal tracks are lost in the large background of accelerated ion tracks. A technique for recovering signal in these scenarios has been developed, tested, and implemented successfully. The technique involves removing material from the surface of the CR-39 to a depth beyond the endpoint ofmore » the ablator ion tracks. The technique preserves signal magnitude (yield) as well as structure in radiograph images. The technique is effective when signal particle range is at least 10 μm deeper than the necessary bulk material removal.« less

Modeling of Steady-state Scenarios for the Fusion Nuclear Science Facility, Advanced Tokamak Approach

NASA Astrophysics Data System (ADS)

Garofalo, A. M.; Chan, V. S.; Prater, R.; Smith, S. P.; St. John, H. E.; Meneghini, O.

2013-10-01

A Fusion National Science Facility (FNSF) would complement ITER in addressing the community identified science and technology gaps to a commercially attractive DEMO, including breeding tritium and completing the fuel cycle, qualifying nuclear materials for high fluence, developing suitable materials for the plasma-boundary interface, and demonstrating power extraction. Steady-state plasma operation is highly desirable to address the requirements for fusion nuclear technology testing [1]. The Advanced Tokamak (AT) is a strong candidate for an FNSF as a consequence of its mature physics base, capability to address the key issues with a more compact device, and the direct relevance to an attractive target power plant. Key features of AT are fully noninductive current drive, strong plasma cross section shaping, internal profiles consistent with high bootstrap fraction, and operation at high beta, typically above the free boundary limit, βN > 3 . Work supported by GA IR&D funding, DE-FC02-04ER54698, and DE-FG02-95ER43309.

Melting temperature and enthalpy variations of phase change materials (PCMs): a differential scanning calorimetry (DSC) analysis

NASA Astrophysics Data System (ADS)

Sun, Xiaoqin; Lee, Kyoung Ok; Medina, Mario A.; Chu, Youhong; Li, Chuanchang

2018-06-01

Differential scanning calorimetry (DSC) analysis is a standard thermal analysis technique used to determine the phase transition temperature, enthalpy, heat of fusion, specific heat and activation energy of phase change materials (PCMs). To determine the appropriate heating rate and sample mass, various DSC measurements were carried out using two kinds of PCMs, namely N-octadecane paraffin and calcium chloride hexahydrate. The variations in phase transition temperature, enthalpy, heat of fusion, specific heat and activation energy were observed within applicable heating rates and sample masses. It was found that the phase transition temperature range increased with increasing heating rate and sample mass; while the heat of fusion varied without any established pattern. The specific heat decreased with the increase of heating rate and sample mass. For accuracy purpose, it is recommended that for PCMs with high thermal conductivity (e.g. hydrated salt) the focus will be on heating rate rather than sample mass.

Scientific and Technical Information Output of the Langley Research Center, for calendar year 1976

NASA Technical Reports Server (NTRS)

1976-01-01

Documents listed include NASA Technical Reports, Technical Notes, Technical Memorandums, Special Publications, Contractor Reports, journal articles, and technical presentations made at Society meetings. NASA formal reports listed are those that were mailed and distributed to the ultimate user. The material presented here is listed first by Division and then under the following headings: (a) Formal Reports, (b) Contractor Reports, (c) Articles and Meeting Presentations, and (d) High Number Technical Memorandums (High TMX's). Under each heading, the material cited authors in alphabetical order. If a report has more than one author and these authors are from different Divisions, the report is listed only once, under the senior author's name.

C2-C3 Anterior Cervical Fusion: Technical Report.

PubMed

Finn, Michael A; MacDonald, Joel D

2016-12-01

Retrospective review of patients at a university hospital. To describe the anterior approach for cervical discectomy and fusion (ACDF) at C2-C3 level and evaluate its suitability for treatment of instability and degenerative disease in this region. The anterior approach is commonly used for ACDF in the lower cervical spine but is used less often in the high cervical spine. We retrospectively reviewed a database of consecutive cervical spine surgeries performed at our institution to identify patients who underwent ACDF at the C2-C3 level during a 10-year period. Demographic data, clinical indications, surgical technique, complications, and immediate results were evaluated. Of the 11 patients (7 female, 4 male; mean age 46 y) identified, 7 were treated for traumatic fractures and 4 for degenerative disk disease. Three patients treated for myelopathy showed improvement in mean Nurick grade from 3.6 to 1.3. Pain was significantly improved in all patients who had preoperative pain. Solid bony fusion was achieved in 5 of 7 patients at 3-month follow-up. Complications included dysphagia in 4 patients (which resolved in 3), aspiration pneumonia, mild persistent dysphonia, and construct failure at C2 requiring posterior fusion. One patient died of a pulmonary embolism 2 weeks postoperatively. ACDF at the C2-C3 level is an option for the treatment of high cervical disease or trauma but is associated with a higher rate of approach-related morbidity. Familiarity with local anatomy may help to reduce complications. ACDF at C2-C3 appears to have a fusion rate similar to ACDF performed at other levels.

Criteria and Planning Guidance for Ex-Plant Harvesting to Support Subsequent License Renewal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ramuhalli, Pradeep; Devanathan, Ram; Meyer, Ryan M.

As U.S. nuclear power plants look to subsequent license renewal (SLR) to operate for a 20-year period beyond 60 years, the U.S. Nuclear Regulatory Commission and the industry will be addressing technical issues around the capability of long-lived passive components to meet their functionality objectives. A key challenge will be to better understand likely materials degradation mechanisms in these components and their impacts on component functionality and margins to safety. Research addressing many of the remaining technical gaps in these areas for SLR may greatly benefit from materials sampled from plants (decommissioned or operating). Because of the cost and inefficiencymore » of piecemeal sampling, there is a need for a strategic and systematic approach to sampling materials from structures, systems, and components (SSC) in both operating and decommissioned plants. This document describes a potential approach for sampling (harvesting) materials that focuses on prioritizing materials for sampling using a number of criteria. These criteria are based on an evaluation of technical gaps identified in the literature, research needs to address these technical gaps, and lessons learned from previous harvesting campaigns. The document also describes a process for planning future harvesting campaigns; such a plan would include an understanding of the harvesting priorities, available materials, and the planned use of the materials to address the technical gaps.« less

ITER activities and fusion technology

NASA Astrophysics Data System (ADS)

Seki, M.

2007-10-01

At the 21st IAEA Fusion Energy Conference, 68 and 67 papers were presented in the categories of ITER activities and fusion technology, respectively. ITER performance prediction, results of technology R&D and the construction preparation provide good confidence in ITER realization. The superconducting tokamak EAST achieved the first plasma just before the conference. The construction of other new experimental machines has also shown steady progress. Future reactor studies stress the importance of down sizing and a steady-state approach. Reactor technology in the field of blanket including the ITER TBM programme and materials for the demonstration power plant showed sound progress in both R&D and design activities.

Concept of DT fuel cycle for a fusion neutron source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anan'ev, S.; Spitsyn, A.V.; Kuteev, B.V.

2015-03-15

A concept of DT-fusion neutron source (FNS) with the neutron yield higher than 10{sup 18} neutrons per second is under design in Russia. Such a FNS is of interest for many applications: 1) basic and applied research (neutron scattering, etc); 2) testing the structural materials for fusion reactors; 3) control of sub-critical nuclear systems and 4) nuclear waste processing (including transmutation of minor actinides). This paper describes the fuel cycle concept of a compact fusion neutron source based on a small spherical tokamak (FNS-ST) with a MW range of DT fusion power and considers the key physics issues of thismore » device. The major and minor radii are ∼0.5 and ∼0.3 m, magnetic field ∼1.5 T, heating power less than 15 MW and plasma current 1-2 MA. The system provides the fuel mixture with equal fractions of D and T (D:T = 1:1) for all FNS technology systems. (authors)« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharp, D.J.; Panitz, J.K.G.; Mattox, D.M.

The erosion of materials by low energy ions is of concern in fusion reactors since high Z impurities in the plasma cause radiation cooling. Ion bombardment of the fusion reactor chamber walls arises from ions of fuel (D, T) material, gaseous impurities (O, C), and impurities from eroded components (Fe, Co, Ni, C, Mo, etc.) being accelerated across the wall sheath potential (0.1 to 1 keV). A Kaufman type ion source has been characterized for use with hydrogen, and subsequently used to determine the relative erosion rates of bulk Mo, C, Cu, coating of TiB/sub 2/, B/sub 4/C, Be, VBe/submore » 12/ and other materials. Ions of hydrogen (Z=1), argon (Z=18), and xenon (Z=54) at acceleration potentials of 250, 500, and 1000 V have been used to determine erosion yields.« less

Investigation of Liquid Metal Embrittlement of Materials for use in Fusion Reactors

NASA Astrophysics Data System (ADS)

Kennedy, Daniel; Jaworski, Michael

2014-10-01

Liquid metals can provide a continually replenished material for the first wall and extraction blankets of fusion reactors. However, research has shown that solid metal surfaces will experience embrittlement when exposed to liquid metals under stress. Therefore, it is important to understand the changes in structural strength of the solid metal materials and test different surface treatments that can limit embrittlement. Research was conducted to design and build an apparatus for exposing solid metal samples to liquid metal under high stress and temperature. The apparatus design, results of tensile testing, and surface imaging of fractured samples will be presented. This work was supported in part by the U.S. Department of Energy, Office of Science, Office of Workforce Development for Teachers and Scientists (WDTS) under the Science Undergraduate Laboratory Internships Program (SULI).

In vitro laser nerve repair: protein solder strip irradiation or irradiation alone?

PubMed

Trickett, I; Dawes, J M; Knowles, D S; Lanzetta, M; Owen, E R

1997-01-01

This study investigated the potential of sutureless nerve repair using two promising laser fusion methods: direct 2 microns irradiation of the epineurium, and protein solder assisted epineurial fusion using a 800 nm laser. Laser anastomosis of the rat sciatic nerve was performed in vitro without stay sutures in two groups of six animals. In the first group, direct laser fusion used a pulsed Cr, Tm: YAG laser. In the second group an albumin-based fluid solder containing the dye indocyanine green was applied to the epineurium, then irradiated with a diode laser. These two techniques were compared with regards to coaptation success and axonal damage. Direct laser welding produced weak bonds despite microscopic investigation of the irradiated nerves showing fusion of the epineurium. The unsatisfactory bonding can be attributed to poor tissue overlap and insufficient protein in the thin epineurium denaturation of underlying axons was also observed. In contrast, the laser solder method produced successful welds with greatly reduced axonal damage, and significantly improved the tensile strength. This study confirmed the technical possibilities of sutureless nerve anastomosis. Laser activated solders enable stronger bonds, by the addition of protein to the anastomosis site, and less thermal damage to underlying tissue through selective absorption of laser energy by dye in the solder. Further in vivo studies are required before drawing final conclusions.

Development of fusogenic glass surfaces that impart spatiotemporal control over macrophage fusion: Direct visualization of multinucleated giant cell formation.

PubMed

Faust, James J; Christenson, Wayne; Doudrick, Kyle; Ros, Robert; Ugarova, Tatiana P

2017-06-01

Implantation of synthetic material, including vascular grafts, pacemakers, etc. results in the foreign body reaction and the formation of multinucleated giant cells (MGCs) at the exterior surface of the implant. Despite the long-standing premise that fusion of mononucleated macrophages results in the formation of MGCs, to date, no published study has shown fusion in context with living specimens. This is due to the fact that optical-quality glass, which is required for the majority of live imaging techniques, does not promote macrophage fusion. Consequently, the morphological changes that macrophages undergo during fusion as well as the mechanisms that govern this process remain ill-defined. In this study, we serendipitously identified a highly fusogenic glass surface and discovered that the capacity to promote fusion was due to oleamide contamination. When adsorbed on glass, oleamide and other molecules that contain long-chain hydrocarbons promoted high levels of macrophage fusion. Adhesion, an essential step for macrophage fusion, was apparently mediated by Mac-1 integrin (CD11b/CD18, α M β 2 ) as determined by single cell force spectroscopy and adhesion assays. Micropatterned glass further increased fusion and enabled a remarkable degree of spatiotemporal control over MGC formation. Using these surfaces, we reveal the kinetics that govern MGC formation in vitro. We anticipate that the spatiotemporal control afforded by these surfaces will expedite studies designed to identify the mechanism(s) of macrophage fusion and MGC formation with implication for the design of novel biomaterials. Copyright © 2017 Elsevier Ltd. All rights reserved.

An automatic fuzzy-based multi-temporal brain digital subtraction angiography image fusion algorithm using curvelet transform and content selection strategy.

PubMed

Momeni, Saba; Pourghassem, Hossein

2014-08-01

Recently image fusion has prominent role in medical image processing and is useful to diagnose and treat many diseases. Digital subtraction angiography is one of the most applicable imaging to diagnose brain vascular diseases and radiosurgery of brain. This paper proposes an automatic fuzzy-based multi-temporal fusion algorithm for 2-D digital subtraction angiography images. In this algorithm, for blood vessel map extraction, the valuable frames of brain angiography video are automatically determined to form the digital subtraction angiography images based on a novel definition of vessel dispersion generated by injected contrast material. Our proposed fusion scheme contains different fusion methods for high and low frequency contents based on the coefficient characteristic of wrapping second generation of curvelet transform and a novel content selection strategy. Our proposed content selection strategy is defined based on sample correlation of the curvelet transform coefficients. In our proposed fuzzy-based fusion scheme, the selection of curvelet coefficients are optimized by applying weighted averaging and maximum selection rules for the high frequency coefficients. For low frequency coefficients, the maximum selection rule based on local energy criterion is applied to better visual perception. Our proposed fusion algorithm is evaluated on a perfect brain angiography image dataset consisting of one hundred 2-D internal carotid rotational angiography videos. The obtained results demonstrate the effectiveness and efficiency of our proposed fusion algorithm in comparison with common and basic fusion algorithms.

Time-dependent modeling of dust injection in semi-detached ITER divertor plasma

NASA Astrophysics Data System (ADS)

Smirnov, Roman; Krasheninnikov, Sergei

2017-10-01

At present, it is generally understood that dust related issues will play important role in operation of the next step fusion devices, i.e. ITER, and in the development of future fusion reactors. Recent progress in research on dust in magnetic fusion devises has outlined several topics of particular concern: a) degradation of fusion plasma performance; b) impairment of in-vessel diagnostic instruments; and c) safety issues related to dust reactivity and tritium retention. In addition, observed dust events in fusion edge plasmas are highly irregular and require consideration of temporal evolution of both the dust and the fusion plasma. In order to address the dust-related fusion performance issues, we have coupled the dust transport code DUSTT and the edge plasma transport code UEDGE in time-dependent manner, allowing modeling of transient dust-induced phenomena in fusion edge plasmas. Using the coupled codes we simulate burst-like injection of tungsten dust into ITER divertor plasma in semi-detached regime, which is considered as preferable ITER divertor operational mode based on the plasma and heat load control restrictions. Analysis of transport of the dust and the dust-produced impurities, and of dynamics of the ITER divertor and edge plasma in response to the dust injection will be presented. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Fusion Energy Sciences, under Award Number DE-FG02-06ER54852.

Checkpoints for vesicular traffic?

PubMed

Fiset, A; Faure, R

2001-01-01

During interphase the transport of material between different intracellular organelles requires accurate regulation of fusiogenic domains. Recent studies on hepatic endosomes indicated that compartmentalized Cdk2-cyclin E complexes act by braking fusion events. These Cdk2 complexes integrate tyrosine phosphorylation and dephosphorylation inputs, resulting in the control of the number of rounds of fusion at discrete domains. This leads to changes in the intracellular location of internalized receptors and ultimately their biological response.

Tritium

DTIC Science & Technology

2011-11-01

fusion energy -production processes of the particular type of reactor using a lithium (Li) blanket or related alloys such as the Pb-17Li eutectic. As such, tritium breeding is intimately connected with energy production, thermal management, radioactivity management, materials properties, and mechanical structures of any plausible future large-scale fusion power reactor. JASON is asked to examine the current state of scientific knowledge and engineering practice on the physical and chemical bases for large-scale tritium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ierardi, Anna Maria; Duka, Ejona; Radaelli, Alessandro

AimTo evaluate the feasibility of image fusion (IF) of pre-procedural arterial-phase CT angiography or MR angiography with intra-procedural fluoroscopy for road-mapping in endovascular treatment of aorto-iliac steno-occlusive disease.Materials and MethodsBetween September and November, 2014, we prospectively evaluated 5 patients with chronic aorto-iliac steno-occlusive disease, who underwent endovascular treatment in the angiography suite. Fusion image road-mapping was performed using angiographic phase CT images or MR images acquired before and intra-procedural unenhanced cone-beam CT. Radiation dose of the procedure, volume of intra-procedural iodinated contrast medium, fluoroscopy time, and overall procedural time were recorded. Reasons for potential fusion imaging inaccuracies were also evaluated.ResultsImagemore » co-registration and fusion guidance were feasible in all procedures. Mean radiation dose of the procedure was 60.21 Gycm2 (range 55.02–63.75 Gycm2). The mean total procedure time was 32.2 min (range 27–38 min). The mean fluoroscopy time was 12 min and 3 s. The mean procedural iodinated contrast material dose was 24 mL (range 20–40 mL).ConclusionsIF gives Interventional Radiologists the opportunity to use new technologies in order to improve outcomes with a significant reduction of contrast media administration.« less

RBM10-TFE3 Renal Cell Carcinoma: A Potential Diagnostic Pitfall Due to Cryptic Intrachromosomal Xp11.2 Inversion Resulting in False-negative TFE3 FISH.

PubMed

Argani, Pedram; Zhang, Lei; Reuter, Victor E; Tickoo, Satish K; Antonescu, Cristina R

2017-05-01

Xp11 translocation renal cell carcinoma (RCC) are defined by chromosome translocations involving the Xp11 breakpoint which results in one of a variety of TFE3 gene fusions. TFE3 break-apart florescence in situ hybridization (FISH) assays are generally preferred to TFE3 immunohistochemistry (IHC) as a means of confirming the diagnosis in archival material, as FISH is less sensitive to the variable fixation which can result in false positive or false negative IHC. Prompted by a case report in the cytogenetics literature, we identify 3 cases of Xp11 translocation RCC characterized by a subtle chromosomal inversion involving the short arm of the X chromosome, resulting in an RBM10-TFE3 gene fusion. TFE3 rearrangement was not detected by conventional TFE3 break-apart FISH, but was suggested by strong diffuse TFE3 immunoreactivity in a clean background. We then developed novel fosmid probes to detect the RBM10-TFE3 gene fusion in archival material. These cases validate RBM10-TFE3 as a recurrent gene fusion in Xp11 translocation RCC, illustrate a source of false-negative TFE3 break-apart FISH, and highlight the complementary role of TFE3 IHC and TFE3 FISH.

Effects of Local Administration of Boric Acid on Posterolateral Spinal Fusion with Autogenous Bone Grafting in a Rodent Model.

PubMed

Kömürcü, Erkam; Özyalvaçlı, Gülzade; Kaymaz, Burak; Gölge, Umut Hatay; Göksel, Ferdi; Cevizci, Sibel; Adam, Gürhan; Ozden, Raif

2015-09-01

Spinal fusion is among the most frequently applied spinal surgical procedures. The goal of the present study was to evaluate whether the local administration of boric acid (BA) improves spinal fusion in an experimental spinal fusion model in rats. Currently, there is no published data that evaluates the possible positive effects if the local administration of BA on posterolateral spinal fusion. Thirty-two rats were randomly divided into four independent groups: no material was added at the fusion area for group 1; an autogenous morselized corticocancellous bone graft was used for group 2; an autogenous morselized corticocancellous bone graft with boric acid (8.7 mg/kg) for group 3; and only boric acid was placed into the fusion area for group 4. The L4-L6 spinal segments were collected at week 6, and the assessments included radiography, manual palpation, and histomorphometry. A statistically significant difference was determined between the groups with regard to the mean histopathological scores (p = 0.002), and a paired comparison was made with the Mann-Whitney U test to detect the group/groups from which the difference originated. It was determined that only the graft + BA practice increased the histopathological score significantly with regard to the control group (p = 0.002). Whereas, there was no statistically significant difference between the groups in terms of the manual assessment of fusion and radiographic analysis (respectively p = 0.328 and p = 0.196). This preliminary study suggests that BA may clearly be useful as a therapeutic agent in spinal fusion. However, further research is required to show the most effective dosage of BA on spinal fusion, and should indicate whether BA effects spinal fusion in the human body.

The Effects of Ketorolac Injected via Patient Controlled Analgesia Postoperatively on Spinal Fusion

PubMed Central

Park, Si-Young; Moon, Seong-Hwan; Park, Moon-Soo; Oh, Kyung-Soo

2005-01-01

Lumbar spinal fusions have been performed for spinal stability, pain relief and improved function in spinal stenosis, scoliosis, spinal fractures, infectious conditions and other lumbar spinal problems. The success of lumbar spinal fusion depends on multifactors, such as types of bone graft materials, levels and numbers of fusion, spinal instrumentation, electrical stimulation, smoking and some drugs such as nonsteroidal anti-inflammatory drugs (NSAIDs). From January 2000 to December 2001, 88 consecutive patients, who were diagnosed with spinal stenosis or spondylolisthesis, were retrospectively enrolled in this study. One surgeon performed all 88 posterolateral spinal fusions with instrumentation and autoiliac bone graft. The patients were divided into two groups. The first group (n=30) was infused with ketorolac and fentanyl intravenously via patient controlled analgesia (PCA) postoperatively and the second group (n=58) was infused only with fentanyl. The spinal fusion rates and clinical outcomes of the two groups were compared. The incidence of incomplete union or nonunion was much higher in the ketorolac group, and the relative risk was approximately 6 times higher than control group (odds ratio: 5.64). The clinical outcomes, which were checked at least 1 year after surgery, showed strong correlations with the spinal fusion status. The control group (93.1%) showed significantly better clinical results than the ketorolac group (77.6%). Smoking had no effect on the spinal fusion outcome in this study. Even though the use of ketorolac after spinal fusion can reduce the need for morphine, thereby decreasing morphine related complications, ketorolac used via PCA at the immediate postoperative state inhibits spinal fusion resulting in a poorer clinical outcome. Therefore, NSAIDs such as ketorolac, should be avoided after posterolateral spinal fusion. PMID:15861498

Data Acquisition Systems

NASA Technical Reports Server (NTRS)

1989-01-01

Technology developed during a joint research program with Langley and Kinetic Systems Corporation led to Kinetic Systems' production of a high speed Computer Automated Measurement and Control (CAMAC) data acquisition system. The study, which involved the use of CAMAC equipment applied to flight simulation, significantly improved the company's technical capability and produced new applications. With Digital Equipment Corporation, Kinetic Systems is marketing the system to government and private companies for flight simulation, fusion research, turbine testing, steelmaking, etc.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The SPS Concept Development and Evaluation Program includes a comparative assessment. An early first step in the assessment process is the selection and characterization of alternative technologies. This document describes the cost and performance (i.e., technical and environmental) characteristics of six central station energy alternatives: (1) conventional coal-fired powerplant; (2) conventional light water reactor (LWR); (3) combined cycle powerplant with low-Btu gasifiers; (4) liquid metal fast breeder reactor (LMFBR); (5) photovoltaic system without storage; and (6) fusion reactor.

Performance Analysis of the Probabilistic Multi-Hypothesis Tracking Algorithm on the SEABAR Data Sets

DTIC Science & Technology

2009-07-01

Performance Analysis of the Probabilistic Multi- Hypothesis Tracking Algorithm On the SEABAR Data Sets Dr. Christian G . Hempel Naval...Hypothesis Tracking,” NUWC-NPT Technical Report 10,428, Naval Undersea Warfare Center Division, Newport, RI, 15 February 1995. [2] G . McLachlan, T...the 9th International Conference on Information Fusion, Florence Italy, July, 2006. [8] C. Hempel, “Track Initialization for Multi-Static Active Sonay

Mirror Material Properties Compiled for Preliminary Design of the Next Generation Space Telescope (30 to 294 Kelvin)

NASA Technical Reports Server (NTRS)

Luz, P. L.; Rice, T.

1998-01-01

This technical memorandum reports on the mirror material properties that were compiled by NASA Marshall Space Flight Center (MSFC) from April 1996 to June 1997 for preliminary design of the Next Generation Space Telescope (NGST) Study. The NGST study began in February 1996, when the Program Development Directorate at NASA MSFC studied the feasibility of the NGST and developed the pre-phase A program for it. After finishing some initial studies and concepts development work on the NGST, MFSC's Program Development Directorate handed this work to the Observatory Projects Office at MSFC and then to NASA Goddard Space Flight Center (GSFC). This technical memorandum was written by MSFC's Preliminary Design Office and Materials and Processes Laboratory for the NGST Optical Telescope Assembly (OTA) team, in Support of NASA GSFC. It contains material properties for 9 mirror Substrate materials, using information from at least 6 industrial Suppliers, 16 textbooks, 44 technical papers, and 130 technical abstracts.

System and method for producing metallic iron

DOEpatents

Bleifuss, Rodney L [Grand Rapids, MN; Englund, David J [Bovey, MN; Iwasaki, Iwao [Grand Rapids, MN; Fosnacht, Donald R [Hermantown, MN; Brandon, Mark M [Charlotte, NC; True, Bradford G [Charlotte, NC

2012-01-17

A hearth furnace 10 for producing metallic iron material has a furnace housing 11 having a drying/preheat zone 12, a conversion zone 13, a fusion zone 14, and optionally a cooling zone 15, the conversion zone 13 is between the drying/preheat zone 12 and the fusion zone 14. A moving hearth 20 is positioned within the furnace housing 11. A hood or separation barrier 30 within at least a portion of the conversion zone 13, fusion zone 14 or both separates the fusion zone 14 into an upper region and a lower region with the lower region adjacent the hearth 20 and the upper region adjacent the lower region and spaced from the hearth 20. An injector introduces a gaseous reductant into the lower region adjacent the hearth 20. A combustion region may be formed above the hood or separation barrier.

Aviation Structural Mechanic, Second Class, 2-13. Military Curriculum Materials for Vocational and Technical Education.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus. National Center for Research in Vocational Education.

This self-paced, individualized course, adapted from military curriculum materials for use in vocational and technical education, teaches students the skills needed to become aviation structural mechanics (second class). The course materials consist of five pamphlets covering the structural maintenance and repair of aircraft. The first pamphlet…

Smart materials and structures: what are they?

NASA Astrophysics Data System (ADS)

Spillman, W. B., Jr.; Sirkis, J. S.; Gardiner, P. T.

1996-06-01

There has been considerable discussion in the technical community on a number of questions concerned with smart materials and structures, such as what they are, whether smart materials can be considered a subset of smart structures, whether a smart structure and an intelligent structure are the same thing, etc. This discussion is both fueled and confused by the technical community due to the truly multidisciplinary nature of this new field. Smart materials and structures research involves so many technically diverse fields that it is quite common for one field to completely misunderstand the terminology and start of the art in other fields. In order to ascertain whether a consensus is emerging on a number of questions, the technical community was surveyed in a variety of ways including via the internet and by direct contact. The purpose of this survey was to better define the smart materials and structures field, its current status and its potential benefits. Results of the survey are presented and discussed. Finally, a formal definition of the field of smart materials and structures is proposed.

49 CFR 552.6 - Technical review.

Code of Federal Regulations, 2010 CFR

2010-10-01

... § 552.6 Technical review. The appropriate Associate Administrator conducts a technical review of the petition. The technical review may consist of an analysis of the material submitted, together with... 49 Transportation 6 2010-10-01 2010-10-01 false Technical review. 552.6 Section 552.6...

49 CFR 552.6 - Technical review.

Code of Federal Regulations, 2011 CFR

2011-10-01

... § 552.6 Technical review. The appropriate Associate Administrator conducts a technical review of the petition. The technical review may consist of an analysis of the material submitted, together with... 49 Transportation 6 2011-10-01 2011-10-01 false Technical review. 552.6 Section 552.6...

Analytical method for thermal stress analysis of plasma facing materials

NASA Astrophysics Data System (ADS)

You, J. H.; Bolt, H.

2001-10-01

The thermo-mechanical response of plasma facing materials (PFMs) to heat loads from the fusion plasma is one of the crucial issues in fusion technology. In this work, a fully analytical description of the thermal stress distribution in armour tiles of plasma facing components is presented which is expected to occur under typical high heat flux (HHF) loads. The method of stress superposition is applied considering the temperature gradient and thermal expansion mismatch. Several combinations of PFMs and heat sink metals are analysed and compared. In the framework of the present theoretical model, plastic flow and the effect of residual stress can be quantitatively assessed. Possible failure features are discussed.

Laser-fusion targets for reactors

DOEpatents

Nuckolls, John H.; Thiessen, Albert R.

1987-01-01

A laser target comprising a thermonuclear fuel capsule composed of a centrally located quantity of fuel surrounded by at least one or more layers or shells of material for forming an atmosphere around the capsule by a low energy laser prepulse. The fuel may be formed as a solid core or hollow shell, and, under certain applications, a pusher-layer or shell is located intermediate the fuel and the atmosphere forming material. The fuel is ignited by symmetrical implosion via energy produced by a laser, or other energy sources such as an electron beam machine or ion beam machine, whereby thermonuclear burn of the fuel capsule creates energy for applications such as generation of electricity via a laser fusion reactor.

Tantalum coatings for inertial confinement fusion dry wall designs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, L.H.; Green, L.

1996-12-31

The coating on a dry first wall inertial confinement fusion reactor must survive the target explosion and be ductile, inexpensive, and compatible with the materials in the target, i.e. have a high atomic number Z. Calculations indicate that tantalum is the best choice for the coating material. As a test of this design 1 mm tantalum coatings were plasma sprayed onto ferrite steel tubes. They were then subjected to 100 heating-cooling cycles which simulated the stressful thermal cycling which would be encountered during five years of plant startups and shutdowns. The coatings were undamaged and continued to bond well tomore » the steel. Furthermore, chemical reactions should not degrade tantalum coatings.« less

Addressing Research and Development Gaps for Plasma-Material Interactions with Linear Plasma Devices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rapp, Juergen

Plasma-material interactions in future fusion reactors have been identified as a knowledge gap to be dealt with before any next step device past ITER can be built. The challenges are manifold. They are related to power dissipation so that the heat fluxes to the plasma-facing components can be kept at technologically feasible levels; maximization of the lifetime of divertor plasma-facing components that allow for steadystate operation in a reactor to reach the neutron fluence required; the tritium inventory (storage) in the plasma-facing components, which can lead to potential safety concerns and reduction in the fuel efficiency; and it is relatedmore » to the technology of the plasma-facing components itself, which should demonstrate structural integrity under the high temperatures and high neutron fluence. While the dissipation of power exhaust can and should be addressed in high power toroidal devices, the interaction of the plasma with the materials can be best addressed in dedicated linear devices due to their cost effectiveness and ability to address urgent research and development gaps more timely. However, new linear plasma devices are needed to investigate the PMI under fusion reactor conditions and test novel plasma-facing components. Existing linear devices are limited either in their flux, their reactor-relevant plasma transport regimes in front of the target, their fluence, or their ability to test material samples a priori exposed to high neutron fluence. The proposed Material Plasma Exposure eXperiment (MPEX) is meant to address those deficiencies and will be designed to fulfill the fusion reactor-relevant plasma parameters as well as the ability to expose a priori neutron activated materials to plasmas.« less

The Complete Burning of Weapons Grade Plutonium and Highly Enriched Uranium with (Laser Inertial Fusion-Fission Energy) LIFE Engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farmer, J C; Diaz de la Rubia, T; Moses, E

2008-12-23

The National Ignition Facility (NIF) project, a laser-based Inertial Confinement Fusion (ICF) experiment designed to achieve thermonuclear fusion ignition and burn in the laboratory, is under construction at the Lawrence Livermore National Laboratory (LLNL) and will be completed in April of 2009. Experiments designed to accomplish the NIF's goal will commence in late FY2010 utilizing laser energies of 1 to 1.3 MJ. Fusion yields of the order of 10 to 20 MJ are expected soon thereafter. Laser initiated fusion-fission (LIFE) engines have now been designed to produce nuclear power from natural or depleted uranium without isotopic enrichment, and from spentmore » nuclear fuel from light water reactors without chemical separation into weapons-attractive actinide streams. A point-source of high-energy neutrons produced by laser-generated, thermonuclear fusion within a target is used to achieve ultra-deep burn-up of the fertile or fissile fuel in a sub-critical fission blanket. Fertile fuels including depleted uranium (DU), natural uranium (NatU), spent nuclear fuel (SNF), and thorium (Th) can be used. Fissile fuels such as low-enrichment uranium (LEU), excess weapons plutonium (WG-Pu), and excess highly-enriched uranium (HEU) may be used as well. Based upon preliminary analyses, it is believed that LIFE could help meet worldwide electricity needs in a safe and sustainable manner, while drastically shrinking the nation's and world's stockpile of spent nuclear fuel and excess weapons materials. LIFE takes advantage of the significant advances in laser-based inertial confinement fusion that are taking place at the NIF at LLNL where it is expected that thermonuclear ignition will be achieved in the 2010-2011 timeframe. Starting from as little as 300 to 500 MW of fusion power, a single LIFE engine will be able to generate 2000 to 3000 MWt in steady state for periods of years to decades, depending on the nuclear fuel and engine configuration. Because the fission blanket in a fusion-fission hybrid system is subcritical, a LIFE engine can burn any fertile or fissile nuclear material, including unenriched natural or depleted U and SNF, and can extract a very high percentage of the energy content of its fuel resulting in greatly enhanced energy generation per metric ton of nuclear fuel, as well as nuclear waste forms with vastly reduced concentrations of long-lived actinides. LIFE engines could thus provide the ability to generate vast amounts of electricity while greatly reducing the actinide content of any existing or future nuclear waste and extending the availability of low cost nuclear fuels for several thousand years. LIFE also provides an attractive pathway for burning excess weapons Pu to over 99% FIMA (fission of initial metal atoms) without the need for fabricating or reprocessing mixed oxide fuels (MOX). Because of all of these advantages, LIFE engines offer a pathway toward sustainable and safe nuclear power that significantly mitigates nuclear proliferation concerns and minimizes nuclear waste. An important aspect of a LIFE engine is the fact that there is no need to extract the fission fuel from the fission blanket before it is burned to the desired final level. Except for fuel inspection and maintenance process times, the nuclear fuel is always within the core of the reactor and no weapons-attractive materials are available outside at any point in time. However, an important consideration when discussing proliferation concerns associated with any nuclear fuel cycle is the ease with which reactor fuel can be converted to weapons usable materials, not just when it is extracted as waste, but at any point in the fuel cycle. Although the nuclear fuel remains in the core of the engine until ultra deep actinide burn up is achieved, soon after start up of the engine, once the system breeds up to full power, several tons of fissile material is present in the fission blanket. However, this fissile material is widely dispersed in millions of fuel pebbles, which can be tagged as individual accountable items, and thus made difficult to divert in large quantities. This report discusses the application of the LIFE concept to nonproliferation issues, initially looking at the LIFE (Laser Inertial Fusion-Fission Energy) engine as a means of completely burning WG Pu and HEU. By combining a neutron-rich inertial fusion point source with energy-rich fission, the once-through closed fuel-cycle LIFE concept has the following characteristics: it is capable of efficiently burning excess weapons or separated civilian plutonium and highly enriched uranium; the fission blanket is sub-critical at all times (keff < 0.95); because LIFE can operate well beyond the point at which light water reactors (LWRs) need to be refueled due to burn-up of fissile material and the resulting drop in system reactivity, fuel burn-up of 99% or more appears feasible. The objective of this work is to develop LIFE technology for burning of WG-Pu and HEU.« less

[Mechanical studies of lumbar interbody fusion implants].

PubMed

Bader, R J; Steinhauser, E; Rechl, H; Mittelmeier, W; Bertagnoli, R; Gradinger, R

2002-05-01

In addition to autogenous or allogeneic bone grafts, fusion cages composed of metal or plastic are being used increasingly as spacers for interbody fusion of spinal segments. The goal of this study was the mechanical testing of carbon fiber reinforced plastic (CFRP) fusion cages used for anterior lumbar interbody fusion. With a special testing device according to American Society for Testing and Materials (ASTM) standards, the mechanical properties of the implants were determined under four different loading conditions. The implants (UNION cages, Medtronic Sofamor Danek) provide sufficient axial compression, shear, and torsional strength of the implant body. Ultimate axial compression load of the fins is less than the physiological compression loads at the lumbar spine. Therefore by means of an appropriate surgical technique parallel grooves have to be reamed into the endplates of the vertebral bodies according to the fin geometry. Thereby axial compression forces affect the implants body and the fins are protected from damaging loading. Using a supplementary anterior or posterior instrumentation, in vivo failure of the fins as a result of physiological shear and torsional spinal loads is unlikely. Due to specific complications related to autogenous or allogeneic bone grafts, fusion cages made of metal or carbon fiber reinforced plastic are an important alternative implant in interbody fusion.

[Application of a stand-alone interbody fusion cage based on a novel porous TiO2/glass composite. I. Implantation in the sheep cervical spine and radiological evaluation].

PubMed

Korinth, M C; Hero, T; Mahnken, A H; Ragoss, C; Scherer, K

2004-12-01

Animals are becoming more and more common as in vitro and in vivo models for the human spine. Especially the sheep cervical spine is stated to be of good comparability and usefulness in the evaluation of in vivo radiological, biomechanical and histological behaviour of new bone replacement materials, implants and cages for cervical spine interbody fusion. In preceding biomechanical in vitro examination human cervical spine specimens were tested after fusion with either a cubical stand-alone interbody fusion cage manufactured from a new porous TiO/glass composite (Ecopore) or polymethyl-methacrylate (PMMA) after discectomy. First experience with the use of the new material and its influence on the primary stability after in vitro application were gained. After fusion of 10 sheep cervical spines in the levels C2/3 and C4/5 in each case with PMMA and with an Ecopore-cage, radiologic as well as computertomographic examinations were performed postoperatively and every 4 weeks during the following 2 and 4 months, respectively. Apart from establishing our animal model, we analysed the radiological changes and the degree of bony fusion of the operated segments during the course. In addition we performed measurements of the corresponding disc space heights (DSH) and intervertebral angles (IVA) for comparison among each other, during the course and with the initial values. Immediately after placement of both implants in the disc spaces the mean DSH and IVA increased (34.8% and 53.9%, respectively). During the following months DSH decreased to a greater extent in the Ecopore-segments than in the PMMA-segments, even to a value below the initial value (p>0.05). Similarly, the IVA decreased in both groups in the postoperative time lapse, but more distinct in the Ecopore-segments (p<0.05). These changes in terms of a subsidence of the implants, were confirmed morphologically in the radiological examination in the course. The radiologically evaluated fusion, i.e. bony bridging of the operated segments, was more pronounced after implantation of an Ecopore-cage (83%), than after PMMA interposition (50%), but did not gain statistical significance. In this first in vivo examination of our new porous ceramic bone replacement material we showed its application in the spondylodesis model of the sheep cervical spine. Distinct radiological changes regarding evident subsidence and detectable fusion of the segments, operated on with the new biomaterial, were seen. We demonstrated the radiological changes of the fused segments during several months and analysed them morphologically, before the biomechanical evaluation will be presented in a subsequent publication.

Energy Materials Coordinating Committee (EMaCC). Annual technical report, Fiscal Year 2001

DOE Office of Scientific and Technical Information (OSTI.GOV)

None, None

2002-08-01

The DOE Energy Materials Coordinating Committee (EMaCC) serves primarily to enhance coordination among the Department's materials programs and to further effective use of materials expertise within the Department. These functions are accomplished through the exchange of budgetary and planning information among program managers and through technical meetings/workshops on selected topics involving both DOE and major contractors. In addition, EMaCC assists in obtaining materials-related inputs for both intra- and interagency compilations.

Postirradiation thermocyclic loading of ferritic-martensitic structural materials

NASA Astrophysics Data System (ADS)

Belyaeva, L.; Orychtchenko, A.; Petersen, C.; Rybin, V.

Thermonuclear fusion reactors of the Tokamak-type will be unique power engineering plants to operate in thermocyclic mode only. Ferritic-martensitic stainless steels are prime candidate structural materials for test blankets of the ITER fusion reactor. Beyond the radiation damage, thermomechanical cyclic loading is considered as the most detrimental lifetime limiting phenomenon for the above structure. With a Russian and a German facility for thermal fatigue testing of neutron irradiated materials a cooperation has been undertaken. Ampule devices to irradiate specimens for postirradiation thermal fatigue tests have been developed by the Russian partner. The irradiation of these ampule devices loaded with specimens of ferritic-martensitic steels, like the European MANET-II, the Russian 05K12N2M and the Japanese Low Activation Material F82H-mod, in a WWR-M-type reactor just started. A description of the irradiation facility, the qualification of the ampule device and the modification of the German thermal fatigue facility will be presented.

Plasma Surface Interactions Common to Advanced Fusion Wall Materials and EUV Lithography - Lithium and Tin

NASA Astrophysics Data System (ADS)

Ruzic, D. N.; Alman, D. A.; Jurczyk, B. E.; Stubbers, R.; Coventry, M. D.; Neumann, M. J.; Olczak, W.; Qiu, H.

2004-09-01

Advanced plasma facing components (PFCs) are needed to protect walls in future high power fusion devices. In the semiconductor industry, extreme ultraviolet (EUV) sources are needed for next generation lithography. Lithium and tin are candidate materials in both areas, with liquid Li and Sn plasma material interactions being critical. The Plasma Material Interaction Group at the University of Illinois is leveraging liquid metal experimental and computational facilities to benefit both fields. The Ion surface InterAction eXperiment (IIAX) has measured liquid Li and Sn sputtering, showing an enhancement in erosion with temperature for light ion bombardment. Surface Cleaning of Optics by Plasma Exposure (SCOPE) measures erosion and damage of EUV mirror samples, and tests cleaning recipes with a helicon plasma. The Flowing LIquid surface Retention Experiment (FLIRE) measures the He and H retention in flowing liquid metals, with retention coefficients varying between 0.001 at 500 eV to 0.01 at 4000 eV.

Survey of Materials for Fusion Fission Hybrid Reactors Vol 1 Rev. 0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farmer, Joseph Collin

2007-07-03

Materials for fusion-fission hybrid reactors fall into several broad categories, including fuels, blanket and coolant materials, cladding, structural materials, shielding, and in the specific case of inertial-confinement fusion systems, laser and optical materials. This report surveys materials in all categories of materials except for those required for lasers and optics. Preferred collants include two molten salt mixtures known as FLIBE (Li2BeF4) and FLINABE (LiNaBeF4). In the case of homogenous liquid fuels, UF4 can be dissolved in these molten salt mixtures. The transmutation of lithium in this coolant produces very corrosive hydrofluoric acid species (HF and TF), which can rapidly degrademore » structural materials. Broad ranges of high-melting radiation-tolerant structural material have been proposed for fusion-fission reactor structures. These include a wide variety of steels and refractory alloys. Ferritic steels with oxide-dispersion strengthening and graphite have been given particular attention. Refractory metals are found in Groups IVB and VB of the periodic table, and include Nb, Ta, Cr, Mo, and W, as serve as the basis of refractory alloys. Stable high-melting composites and amorphous metals may also be useful. Since amorphous metals have no lattice structure, neutron bombardment cannot dislodge atoms from lattice sites, and the materials would be immune from this specific mode of degradation. The free energy of formation of fluorides of the alloying elements found in steels and refractory alloys can be used to determine the relative stability of these materials in molten salts. The reduction of lithium transmutation products (H + and T +) drives the electrochemical corrosion process, and liberates aggressive fluoride ions that pair with ions formed from dissolved structural materials. Corrosion can be suppressed through the use of metallic Be and Li, though the molten salt becomes laden with colloidal suspensions of Be and Li corrosion products in the process. Alternatively, imposed currents and other high-temperature cathodic protection systems are envisioned for protection of the structural materials. This novel concept could prove to be enabling technology for such high-temperature molten-salt reactors. The use of UF 4 as a liquid-phase homogenous fuel is also complicated by redox control. For example, the oxidation of tetravalent uranium to hexavalent uranium could result in the formation of volatile UF 6. This too could be controlled through electrochemically manipulated oxidation and reduction reactions. In situ studies of pertinent electrochemical reactions in the molten salts are proposed, and are relevant to both the corrosive attack of structural materials, as well as the volatilization of fuel. Some consideration is given to the potential advantages of gravity fed falling-film blankets. Such systems may be easier to control than vortex systems, but would require that cylindrical reaction vessels be oriented with the centerline normal to the gravitational field.« less