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At least 91 records · Page 5

Development Unit Configuration and Current Status of the MIP/MTERC Experiment

The Mars In-Situ Propellant Production (ISPP) Precursor (MIP) experiment package is planned for inclusion on the Mars 2001 Lander. This experiment package consists of five experiments whose purpose is to demonstrate the performance of various ISPP processes in-situ on Mars. The demonstrated ability to produce propellant for Mars Return Vehicles (MRV) is considered to be a necessary precursor to any future manned mission to Mars. The Mars Thermal Environment/Radiator Characterization (MTERC) experiment is part of the MIP package and is intended to determine the Mars night sky temperature as well as to characterize the performance degradation of radiators caused by environmental exposure on Mars over time. Radiators are needed as part of the ISPP process to remove heat from the Mars Atmosphere Acquisition and Compression (MAAC) C02 sorption compressor. MTERC will provide the data needed to optimize the design of radiators for ISPP and other processes. A MTERC Development Unit (DU) has been fabricated and tested at JPL. The MTERC DU consists of: (1) a radiator subassembly, (2) a motor/cover subassembly, (3) a differential temperature control circuit and motor control electronics circuit board, and (4) a command and data handling electronics circuit board. This paper will describe the operational theory and the configuration of the MTERC DU and will discuss the current status of the MTERC experiment development including some selected results of performance testing that has been completed prior to the ISRU III meeting.

Juanero, K. J.↗

Current Status of the Russian Research Reactor Fuel Return Program

In 1999, the U.S. Department of Energy (DOE), together with the International Atomic Energy Agency (IAEA) and the Russian Federation, agreed to start a new nuclear non-proliferation initiative to return Russian/Soviet-origin highly enriched uranium (HEU) back to its country of origin. Trilateral discussions among the U.S., the Russian Federation, and the IAEA identified more than 20 research reactors in 16 countries (Belarus, Bulgaria, China, Czech Republic, DPRK, Germany, Hungary, Kazakhstan, Latvia, Libya, Poland, Romania, Serbia, Ukraine, Uzbekistan, and Vietnam) that had Russian/Soviet-origin HEU. In 2000, the IAEA Director General sent a letter to 16 countries asking for their willingness to return this spent HEU fuel to the Russian Federation. Fourteen countries responded positively to the Director General’s letter. The primary goal of the Russian Research Reactor Fuel Return (RRRFR) program, managed by DOE’s National Nuclear Security Administration, Office of Material Management and Minimization, is to advance nuclear nonproliferation objectives by encouraging eligible countries to convert their research reactors from HEU to low-enriched uranium (LEU) fuel and to eliminate stockpiles of HEU. In May 2004, the United States and the Russian Federation signed a Government-to-Government Agreement that established the legal framework necessary for cooperation between the United States and the Russian Federation for the return of research/test reactor fuel from eligible countries. To date, the RRRFR program has completed sixty-three successful operations to repatriate almost 2,300 kg of Russian-origin HEU fresh and spent fuel. All Russian-origin HEU has been completely removed from 12 countries: Bulgaria, the Czech Republic, Hungary, Georgia, Latvia, Libya, Poland, Romania, Serbia, Ukraine, Uzbekistan, and Vietnam. At the present time Russian-origin HEU remains in Kazakhstan, Belarus, Germany, DPRK, and China. This paper describes the current status of the RRRFR program and preparations for upcoming HEU removal and down-blending activities.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Development Unit Configuration and Current Status of the MIP/MAAC Experiment

The Mars In-Situ Propellant Production (ISPP) Precursor (MIP) experiment package is planned for inclusion on the Mars 2001 Lander. This experiment package consists of five experiments whose purpose is to demonstrate the performance of various ISPP processes in-situ on Mars. The demonstrated ability to produce propellant for Mars Return Vehicles (MRV) is considered to be a necessary precursor to any future manned mission to Mars. The Mars Atmosphere Acquisition and Compression (MAAC) experiment is part of the MIP package and is intended to demonstrate that, by using a sorption compressor, CO2 can be preferentially adsorbed at about 6 torr from the Mars atmosphere during the night when the bed is cold then subsequently compressed to about 800 torr by heating the bed and desorbing CO2 during the day. The compressed CO2 produced by MAAC is to be fed to the Oxygen Generator Subsystem (OGS) where pure oxygen is to be produced. Pure oxygen is considered to be one of the primary constituents of a future manned MRV propellant system. A MAAC Development Unit (DU) has been fabricated and tested at JPL. The MAAC DU consists of 1) a sorption bed filled with a CO2 selective sorbent material, 2) a purge system to be used to periodically backflush non-CO2 gases from the sorbent bed during adsorption, 3) a JPL-developed gas-gap heat switch that allows heat transfer to a radiator for heat removal from the bed during the night time adsorption period and that impedes heat transfer during the day time desorption period, 4) a radiator to radiate heat to the night sky during the adsorption period, 5) a set of three isolation valves and connecting tubing. 6) two pressure transducers and several thermocouples for monitoring the MAAC operating conditions, and command and data handling electronics. This paper will describe the operational theory and the configuration of the MAAC DU and will discuss the current status of the MAAC experiment development including some selected results of performance testing that has been completed prior to the ISRU III meeting.

Karlmann, P. B.↗

Current status of the Explosive Transient Camera

The current configuration and performance of the Explosive Transient Camera (ETC), a wide-field sky monitor capable of detecting short-timescale optical transients, are briefly reviewed, as are plans for future improvements. The primary objective of the ETC is to detect an optical transient that is spatially and temporally coincident with a gamma-ray burster. However, the ETC is sensitive to all sources of short-timescale optical transients and will conduct a systematic survey of the night sky for all optical transients. Results of preliminary observations of the night sky conducted since January 1991 are summarized, and long-term variability searches with the ETC are discussed.

Vanderspek, Roland↗

Current Status of the Nitrogen Oxygen Recharge System

This paper presents an overview of the Nitrogen Oxygen Recharge System (NORS) to date and the current development status of the system. NORS is an element of the International Space Station (ISS) Environmental Control and Life Support Systems (ECLSS) used to resupply the ISS with Nitrogen and Oxygen following the impending retirement of the Space Shuttle. The paper will discuss why NASA is developing NORS, including a summary of other concepts considered, and other related concepts currently being developed by NASA. The current system architecture will be described, along with a summary of the current design of the NORS. The overall programmatic schedule of the NORS in the context of the upcoming shuttle retirement and future launch vehicle development will also be presented. Finally, the paper will examine the significant technical challenges encountered during the requirements and preliminary design phase of NORS development. A key challenge to the development of NORS is the international shipment - and associated regulations - of pressurized Oxygen, which is necessary due to the use of launch vehicles based in Japan and French Guiana to send NORS gasses to the ISS. The storage and use of relatively large quantities of high pressure (41,000 kPa) Oxygen and Nitrogen within the ISS, which is unprecedented both on the ISS and other space vehicles, has had a significant impact on the design and architecture of the system. The high pressure of the system also poses unique thermal considerations, which has led to the development of a heater system for thermal conditioning of high pressure gas to avoid thermal impacts on downstream hardware. The on-orbit envelope allocated to the NORS has changed (gotten smaller) and has impacted both the design and architecture of the system. Finally, the balance of safety considerations associated with these high pressure gasses, particularly high pressure Oxygen, with the functionality of the system has profoundly impacted the form of the system and will be discussed.

Dick, Brandon↗

Horizontal Splitter Design For FFA@CEBAF Energy Upgrade: Current Status

Thomas Jefferson National Accelerator Facility (Jefferson Lab) is currently studying the feasibility of an energy upgrade based upon Fixed-Field Alternating Gradient (FFA) permanent magnet technology. The current plan is to replace the highest-energy recirculation arcs with FFA arcs, increasing the total number of beam recirculations, thus the energy. In order to accommodate multiple passes in the FFA arcs, horizontal splitters are being designed to control the beam parameters entering the FFA arcs, as well as the time of flight and R_56. In the current design, six passes will recirculate through the FFA arcs, necessitating the design of six independent beamlines to control the optics and beam dynamics matching into the arcs. These beamlines must fit into the current CEBAF tunnel, while allowing for personnel and equipment access. They must also be flexible enough to accommodate the beam under realistic operational conditions and fluctuations. The constraints on the system are highly restrictive, complicating the design. This document will describe the current state of the design, and indicate the work remaining for a complete conceptual design.

Benesch, Jay↗

VTOL and VSTOL handling qualities specifications, an overview of the current status

The highlights of a comparative analysis between the current helicopter and VSTOL specifications and four representative rotary wing aircraft are presented. Longitudinal, lateral, and directional control power and dynamic stability characteristics were analyzed for hovering conditions. Forward flight static and dynamic stability were analyzed for the longitudinal and lateral-directional axes. Results of the analyses in terms of the applicability/utility of the MIL-H-8501A criteria are presented for each of the above areas. The review of the MIL-H-8301A criteria against those in MIL-F-83300 and AGARD 577 indicate many areas in which MIL-H-8501A does not give adequate design guidance.

Goldstein, K. W.↗

Early stages of solar flares - Current status of our understanding and opportunities for future observations

Current models of the energy release and transport mechanisms occurring in solar flares are updated to include the input from data collected with the SMM satellite. The new data cover numerous solar flares observed in X-ray and gamma ray bands over a 6 yr period, combined with data from the Japanese Hinori satellite in 1981-82 and ground-based radio observations. The 300 keV gamma ray data have been instrumental in revealing a 152-158 day period in the frequency of solar flares. Recent analysis has indicated that the periodicity is connected to the rotational spectrum of g-modes in the sun. Other data have shown that hard X-rays are emitted from the footpoints and interactions among coronal magnetic loops, where electron acceleration processes occur that are not well understood. The footpoint emission appear in impulsive events, while the interaction emissions are connected with gradual flares.

Dennis, B. R.↗

SMR Current Status: Development Needs and Global Perspectives

Defined as nuclear reactors with a power output up to 300 megawatts electrical (MWe) by the International Atomic Energy Agency (IAEA) and targeted for multipurpose applications, small modular reactors (SMRs) have been recognized as a very promising, clean, affordable, and sustainable energy source by many countries. At present, more than 80 SMRs are under design, development, demonstration, deployment, and beyond (4D+) phases worldwide. This study focuses on the current world status of SMRs and focuses on the necessary developments to accelerate the process of adopting SMRs as a major energy source globally. SMRs are not a new concept, but they do represent a new vision for older concepts if the challenges inherent within them are mitigated with strategic and realistic solution approaches. The major challenges for SMRs 4D+ like any new reactors are: (a) qualifying the advanced fuel-to-reactor design; (b) supporting rapid scaled/prototypic experimentations; (c) maintaining local and global codes, standards, and licensing; (d) supply chain issues;(e) effective cradle-to-grave nuclear fuel cycle and fuel material transportation, and (f) mitigating financial and environmental risks. These upfront challenges can be mitigated with a synergistic solution approach among the various stakeholders: industry, academia, research, government, and international entities.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Presentation: SMR Current Status: Development Needs and Global Perspectives

Defined as nuclear reactors with a power output up to 300 megawatts electrical (MWe) by the International Atomic Energy Agency (IAEA) and targeted for multipurpose applications, small modular reactors (SMRs) have been recognized as a very promising, clean, affordable, and sustainable energy source by many countries. At present, more than 80 SMRs are under design, development, demonstration, deployment, and beyond (4D+) phases worldwide. This paper focuses on the current world status of SMRs and focuses on the necessary developments to accelerate the process of adopting SMRs as a major energy source globally. SMRs are not a new concept, but they do represent a new vision for older concepts if the challenges inherent within them are mitigated with strategic and realistic solution approaches. The major challenges for SMRs 4D+ like any new reactors are: (a) qualifying the advanced fuel-to-reactor design; (b) supporting rapid scaled/prototypic experimentations; (c) maintaining local and global codes, standards, and licensing; (d) supply chain issues; (e) effective cradle-to-grave nuclear fuel cycle and fuel material transportation, and (f) mitigating financial and environmental risks. These upfront challenges can be mitigated with a synergistic solution approach among the various stakeholders: industry, academia, research, government, and international entities.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

SMR Current Status: Development Needs and Global Perspectives

Defined as nuclear reactors with a power output up to 300 megawatts electrical (MWe) by the International Atomic Energy Agency (IAEA) and targeted for multipurpose applications, small modular reactors (SMRs) have been recognized as a very promising, clean, affordable, and sustainable energy source by many countries. At present, more than 80 SMRs are under design, development, demonstration, deployment, and beyond (4D+) phases worldwide. This study focuses on the current world status of SMRs and focuses on the necessary developments to accelerate the process of adopting SMRs as a major energy source globally. SMRs are not a new concept, but they do represent a new vision for older concepts if the challenges inherent within them are mitigated with strategic and realistic solution approaches. The major challenges for SMRs 4D+ like any new reactors are: (a) qualifying the advanced fuel-to-reactor design; (b) supporting rapid scaled/prototypic experimentations; (c) maintaining local and global codes, standards, and licensing; (d) supply chain issues;(e) effective cradle-to-grave nuclear fuel cycle and fuel material transportation, and (f) mitigating financial and environmental risks. These upfront challenges can be mitigated with a synergistic solution approach among the various stakeholders: industry, academia, research, government, and international entities.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Automotive Li-Ion Batteries: Current Status and Future Perspectives

Lithium-ion batteries (LIBs) are currently the most suitable energy storage device for powering electric vehicles (EVs) owing to their attractive properties including high energy efficiency, lack of memory effect, long cycle life, high energy density and high power density. These advantages allow them to be smaller and lighter than other conventional rechargeable batteries such as lead–acid batteries, nickel–cadmium batteries (Ni–Cd) and nickel–metal hydride batteries (Ni–MH). Modern EVs, however, still suffer from performance barriers (range, charging rate, lifetime, etc.) and technological barriers (high cost, safety, reliability, etc.), limiting their widespread adoption. Given these facts, this review sets the extensive market penetration of LIB-powered EVs as an ultimate objective and then discusses recent advances and challenges of electric automobiles, mainly focusing on critical element resources, present and future EV markets, and the cost and performance of LIBs. Finally, novel battery chemistries and technologies including high-energy electrode materials and all-solid-state batteries are also evaluated for their potential capabilities in next-generation long-range EVs.

25 ENERGY STORAGE↗

Dynamics of QCD matter — current status

In this study, there are 18 sections discussing various current topics in the field of relativistic heavy-ion collisions and related phenomena, which will serve as a snapshot of the current state of the art. Section 1 reviews experimental results of some recent light-flavored particle production data from ALICE collaboration. Other sections are mostly theoretical in nature. Very strong but transient magnetic field created in relativistic heavy-ion collisions could have important observational consequences.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

A Review of the Current Status of Percutaneous Endovascular Arteriovenous Fistula Creation for Haemodialysis Access

Surgical fistulas were first described over 50 years ago and have revolutionized the outlook for millions of dialysis-dependent patients. Despite many developments, results remain sub-optimal with high rates of primary failure and re-intervention to maintain patency. Surgical fistulas are known to fail in part due to intimal hyperplasia leading to stenosis, and vessel manipulation during anastomosis creation can be contributory. New technology is emerging that allows the endovascular creation of fistulas with minimal vessel trauma and the initial results demonstrate encouraging outcomes with high technical success rates, low re-intervention, and failure rates and good usability for hemodialysis. Two such device systems are currently available, and here, we provide an overview of the current global status of endoAVF, patient selection criteria, trial results, technical aspects, re-interventions, and outlook for the future.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Tritium processing for the European test blanket systems: current status of the design and development strategy

Tritium processing technologies of the two European Test Blanket Systems (TBS), HCLL (Helium Cooled Lithium Lead) and HCPB (Helium Cooled Pebble Bed), play an essential role in meeting the main objectives of the TBS experimental campaign in ITER. The compliancy with the ITER interface requirements, in terms of space availability, service fluids, limits on tritium release, constraints on maintenance, is driving the design of the TBS tritium processing systems. Other requirements come from the characteristics of the relevant test blanket module and the scientific programme that has to be developed and implemented. This paper identifies the main requirements for the design of the TBS tritium systems and equipment and, at the same time, provides an updated overview on the current design status, mainly focusing onto the tritium extractor from Pb-16Li and TBS tritium accountancy. Considerations are also given on the possible extrapolation to DEMO breeding blanket. (authors)

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

A General Description and Current Status of Chandra

The third of NASA's four Great Observatories, the Chandra X-ray Observatory, was launched aboard the Shuttle Columbia on July 23, 1999. Using an Inertial Upper Stage and an internal propulsion system, Chandra was raised to a highly elliptical orbit ranging from 10,000 km to 140,000 km. After a successful activation of all spacecraft, telescope and science instrument systems, Chandra began observing celestial targets about 18 months ago. From the start, Chandra has provided spectacular images and spectra for essentially all types of astronomical objects including stars, supernova remnants, normal and active galaxies, and clusters of galaxies. High spatial resolution X-ray images and high resolution X-ray spectra continue to provide 'surprises" essentially every day. The current Observatory status and selected science highlights will be presented in this talk.

Tananbaum, Harvey↗

Current status of the electron transport line from RCS to ESR: RTE line

The electron injection system of the U.S. Electron-Ion Collider (EIC) is located outside of the RHIC tunnel. Electrons beams accelerated by the Rapid Cycling Synchrotron (RCS) must be transported to the Electron Storage Ring (ESR), which resides within the RHIC tunnel. To accomplish this, a dedicated beam transport line, referred to as RTE (RCS-to-ESR) line is being designed. The proposed conceptual design comprises three main sections; RCS extraction, a vertical bend and dispersion suppression region, and ESR injection matching. The extraction section uses pulsed kickers and septum magnets to achieve a total deflection angle of 3 degrees. To align the injection section with ESR, the beamline must provide a vertical elevation of 1.68 m, and an array of FODO cells is used to suppress the vertical dispersion. The total length of the RTE line is approximately 133 m, and this paper presents the current design status and considerations for this transport line.

Accelerator Physics↗

The terrestrial cratering record. I - Current status of observations

The location, size and principle characteristics of the currently known proven and probable terrestrial impact craters are compiled. A crater is classified as proven if the structure is associated with meteoritic fragments, and probable if shock metamorphic effects are observed in the target rocks. Proven impact structures have been found to be Pleistocene to Recent in age, while probable impact structures range from Precambrian to Pleistocene. Diameter and age relationships are used to show that a 20 km impact structure will be recognizable as a crater for up to 600 million years, and smaller structures will have shorter lifetimes. Depth-diameter relationships for terrestrial craters show them to be intrinsically shallower than their lunar counterparts, and a transition in crater morphology from simple, or bowl-shaped with an uplifted rim, to complex, with an uplifted center and a depressed rim, is observed with increasing diameter. Shock metamorphic studies have lead to the identification of the type of bolide at a number of probable impact craters, supporting meteoritic origins.

Grieve, R. A. F.↗