Search NASA⌕ Search

SEARCH · Search NASA

Results for “RADIATION SHIELDING”

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

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Flexible 3D printed silicones for gamma and neutron radiation shielding

Here, resin formulations for direct ink write (DIW) additive manufacturing (AM) were developed for facile customization to shield radiation signatures consisting of a range of gamma radiation and neutron energies in a variety of applications. The resin developed in this work has been formulated to accommodate very high loadings of shielding filler materials: up to 40 wt% bismuth (Bi) metal for gamma radiation shielding, and up to 60 wt% boron-10 ( 10 B) metal for neutron shielding. We report the first instance of a printable resin containing 60 wt% 10 B, which remains flexible after curing despite the high solids content. We demonstrate that these resins can not only tolerate formulation modulation for radiation profile-matched shielding, but they can also be printed in a variety of geometries such that mechanical properties of the printed shield are readily tuned to specific applications. In contrast, most existing shielding materials are rigid, bulky, and do not allow for the complex shapes and mechanical flexibility needed in high-usage applications. This work demonstrates the successful development of a tunable resin for additively manufactured, flexible radiation shielding material, containing high loadings of shielding filler, which can be utilized in harsh radiation environments associated with nuclear materials.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2018

Nuclear analysis generic requirements for fusion applications of radiation shielding - 25639

Radiation shielding engineering and associated nuclear analysis plays an important role in design, operation, maintenance and decommissioning of nuclear fusion devices. Requirements adopted in current analyses are investigated versus basic principles of requirement management and verification and validation aspects. An assessment is proposed to derive applicable product and process requirements from safety principles and transversal function requirements. V and V aspects are extended to cover input and output data. It is concluded that beyond the progress on computational capabilities and technical quality of fusion neutronics shielding analysis, there is the need to develop the underlying procedures and requirement management to satisfy configuration management, quality assurance and safety demonstration needs. (authors)

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2017

04BM XFM Beamline Radiation Shielding Analysis

The radiation shielding of the 04-BM-XFM beam line is analyzed for the gas bremsstrahlung (GB) and synchrotron radiation (SR) sources. The GB as a source originates from the long straight section of the storage ring during normal operation when the primary electrons interact with the residual gas molecules in the beam transport pipe giving rise to bremsstrahlung radiation. When the safety shutters are open, this can stream through the beampipe into the first optical enclosure (FOE) and beyond and can result in a radiation environment that is present at a constant rate.

36 MATERIALS SCIENCE↗
DOE OSTI2015

21-ID ESM Beamline Radiation Shielding Analysis

The radiation shielding analysis of Electron Spectro-Microscopy (ESM, 21ID) at 500 mA is documented in this technical note, including Gas Bremsstrahlung (GB) and Synchrotron Radiation (SR). Figure 1 shows the layout of ESM beam line, which uses 2 undulators (EPU105 or EPU57).

36 MATERIALS SCIENCE↗
DOE OSTI2015

21-ID SIX Beamline Radiation Shielding Analysis

The radiation shielding analysis of Soft Inelastic X-ray Scattering(SIX, 2ID) at 500 mA is documented in this technical note, including Gas Bremsstrahlung (GB) and Synchrotron Radiation (SR).

36 MATERIALS SCIENCE↗
DOE OSTI2018

23-ID CSX Beamline Radiation Shielding Analysis

The radiation shielding analysis of Coherent Soft X-ray Scattering and Polarization (CSX, 23 ID) beamline at 500 mA is documented in this memo, including Gas Bremsstrahlung (GB) and Synchrotron Radiation (SR).

36 MATERIALS SCIENCE↗
DOE OSTI2015

17-BM XFP Beamline Radiation Shielding Analysis

The radiation shielding analysis of X-ray Foot printing for In Vitro and In Vivo Structural Studies of Biological Macromolecules (XFP, 17BM) at 500 mA is documented in this technical note, including Gas Bremsstrahlung (GB) and Synchrotron Radiation (SR).

36 MATERIALS SCIENCE↗
DOE OSTI2023

Copper-nickel electroplating of 3D-printed acrylonitrile butadiene styrene for interference and radiation shielding applications

Here, in this study, electromagnetic and radiation shielding structures were fabricated by 3D printing acrylonitrile butadiene styrene (ABS) structures via fused filament fabrication and electroplating with copper (Cu) and nickel (Ni) metals. Prior to electroplating, the printed ABS materials were made conductive by surface electrodeposition of polypyrrole (PPy). ABS adsorbs the pyrrole monomer, which subsequently polymerizes via oxidation forming conductive PPy layer on the printed structures. The successful anchoring of PPy layer can be attributed to its hydrogen bonding and electrostatic interactions with ABS. Thermal analysis, optical, and electron microscopy equipped with energy dispersive X-ray were employed to characterize the printed shielding structures, while the interference and radiation shielding effectiveness were evaluated using a spectrum analyzer and dosimeter, respectively. The interference shielding was found to be effective at 60 ± 5 dB over relatively small frequency range. Shielding was also apparent against gamma and X-ray ionizing rays, but more significantly effective against beta rays. Furthermore, the Cu/Ni coating was able to reduce any heat-induced dimensional changes for the 3D printed ABS substrate without compromising the mechanical integrity.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Neutron Radiation Shielding Strategies for Glovebox Applications

Practical methods for implementing neutron radiation shielding into glovebox applications is discussed. Basic neutron emission shielding strategy and mathematical modeling is introduced. Typical materials used for shielding are introduced along with cost benefit considerations of each. Two examples of neutron radiation shielding implemented into glovebox applications is presented and discussed.

42 ENGINEERING↗
DOE OSTI2016

17-BM XFP Beamline Radiation Shielding Analysis

The NSLS-II Radiation Shielding Standard [1] states: Radiation exposure to staff and users resulting from National Synchrotron Light Source II (NSLS-II) operations must comply with Brookhaven National Laboratory (BNL) and Department of Energy (DOE) radiation requirements and must be maintained as low as reasonably achievable (ALARA).

36 MATERIALS SCIENCE↗
DOE OSTI2020

Preliminary Criticality and Radiation Shielding Analysis for the Storage and Transfer of MARVEL Reactor Spent Nuclear Fuel

This report documents the results of preliminary nuclear criticality and radiation shielding assessments during transfer and dry storage of irradiated Microreactor Applications Research Validation and Evaluation (MARVEL) reactor fuel at Idaho National Laboratory (INL). The assessments focus on transfer casks and storage canisters that are currently in use at INL, which may be compatible with the irradiated MARVEL reactor fuel. The criticality assessments were performed using the radiation transport code MCNP6 with 37 MARVEL reactor fuel elements in various configurations and scenarios. All transfer and storage configurations under dry conditions were below the assumed criticality safety limit of 0.93. Some storage and transfer configurations under wet conditions exceeded the criticality safety limit. This suggests that the appropriate administrative and engineering controls, in addition to reducing the number of MARVEL reactor fuel elements per transfer cask or storage canister, can be expected to ensure criticality safety under all scenarios. The radiation shielding assessments were performed by generating conservative neutron and photon source terms using the ORIGEN module in the SCALE suite of codes. These source spectra were used to estimate the dose equivalent rates using the radiation transport code MCNP6, both on contact and 1 m away from the fuel and transfer casks. The maximum estimated dose equivalent rate of 37 unshielded MARVEL reactor fuel elements on contact is approximately 42000 R/hr. The maximum estimated dose equivalent rates on contact to the ATR transfer cask, HFEF-5 transfer cask, and high load charger were approximately 233 mR/hr, 171 mR/hr, and 201 mR/hr, respectively. This suggests that with the appropriate administrative and engineering controls, all three transfer casks analyzed can be expected to provide sufficient radiation shielding to workers during transfer of irradiated MARVEL reactor fuel. These calculations are performed to support the planning and strategy for the MARVEL project and will demonstrate the technical viability of the different configurations discussed and help identify where engineered or administrative controls may be necessary. A complete criticality safety analysis and radiation shielding analysis, including validation and contingency and accident analysis must be completed by licensed and authorized personnel before any transfer or storage of MARVEL reactor nuclear fuel.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2015

Neutron radiation shielding material polyethylene: consequences of gamma irradiation - 15062

High and ultra-high molecular weight polyethylenes are high performance materials, which are predestined for a wide range of applications due to characteristics like high density, low weight, good dimensional stability, high chemical resistance, and high hydrogen content. These polymers are used in two demanding areas: as implant material in medical technology (only ultra-high molecular weight polyethylenes) and as a component for neutron shielding purposes in casks for storage and transport of radioactive waste. In the medical field (joint replacements) as well as during neutron radiation shielding application, high and ultra-high molecular weight polyethylenes are exposed to gamma irradiation: in the first case requested as sterilization process and for surface-crosslinking and in the second case existing as a side effect of inserting the radioactive material in the cask. Given that polyethylene as shielding material has to withstand any type of degradation affecting safety relevant aspects to be applicable for long-term radiation shielding purposes for instance over a period of 40 years, the durability of the material is of special interest. High molecular weight polyethylene (HMW-PE; LUPOLEN 5261Z; Lyondell Basell) and ultra-high molecular weight polyethylene (UHMW-PE; GUR 4120; Ticona) were subjected to gamma radiation and afterwards thermally treated. The gamma doses used are in the range of 50 to 600 kGy and irradiation takes place at RT using a Co-60 source. The planned thermal treatment will take place at a temperature of 125 deg.C for periods of minimum 30 days and maximum of five years. With the applied conventional analytical techniques it is possible to detect structural changes of both types of polyethylene induced by gamma irradiation and certainly of thermal treatment. Through gamma irradiation melting temperature, crystallinity, and density, respectively increased. Furthermore both polyethylenes get oxidized and cross-linked. With regard to the special application as neutron radiation shielding material in casks for storage and transport of radioactive materials, the impact of irradiation lead to changes of material properties. A consolidated view indicates that the detected changes of the irradiated (U)HMW-PE are not safety relevant for long-term neutron radiation shielding purposes over a period of 40 years in Germany. (authors)

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

Investigation of P(VDF-TrFE)/ZrO{sub 2}-MMA polymer composites applied to radiation shielding

Exposure to high radiation dose in medical diagnostic imaging procedures can lead patients to suffer tissue damaging. However, there are several studies that identify significant dose reduction with the use of radiation protective attenuators, minimizing the delivered dose in the region that covers the main beam, while preserving the diagnostic quality of the generated image. Most radiation attenuator materials are produced from shielding metal containing composites, whose efficiency is the goal of investigations around the world. In this context, polymeric materials were chosen for this investigation in order to provide light-weighted and flexible protective composites, a must in personal protective shielding. Therefore, this work is concerned to the investigation of poly(vinylidene fluoride - try-fluor-ethylene) [P(VDF-TrFE)] copolymers mixed with zirconia nanoparticles. The resulting polymer composites, prepared with 1, 2, 3, 5 and 10 at.% of ZrO{sub 2} nanoparticles, were investigated for application as protective shielding in some interventional radiology procedures. Two variety of composites were produced, one using pure ZrO{sub 2} nanoparticles and the other using sol-gel route with zirconium butoxide as the precursor for zirconium oxide nano-clusters. The P(VDFTrFE)/ ZrO2-MMA polymer composites produced by sol-gel route have provided a much better dispersion of the pure ZrO{sub 2} material into the P(VDF-TrFE) host matrix. UV-Vis and FTIR spectrometry and differential scanning calorimetry (DSC) were used to characterize the composite samples. FTIR data reveal a possible link between the MMA monomers with the P(VDF-TrFE) chain through shared C=O bonds. The radiation shielding characterization was conducted by using a 70 kV x-rays beam which is applicable, for instances, in catheter angiography. The results demonstrate that composites with 10% of ZrO{sub 2}, and only 1.0 mm thick, can attenuate 60% of the x-rays beam. The composite density was evaluated to be 2.20 g/cm{sup 3}. The results indicate that P(VDF-TrFE)/ZrO{sub 2}-MMA polymer composites have potential to be investigated as light-weighted and flexible protective shielding for application in some radiological procedures that uses low kilovoltage x-ray beams. (authors)

36 MATERIALS SCIENCE↗
DOE OSTI2018

10-ID IXS Beamline Radiation Shielding Analysis

This note documents the radiation shielding analysis of Inelastic X-ray Scattering (IXS, 10 ID) beamline at 500 mA, including Gas Bremsstrahlung (GB) and Synchrotron Radiation (SR).

36 MATERIALS SCIENCE↗
DOE OSTI2018

28-ID XPD Beamline Radiation Shielding Analysis

This note documents the radiation shielding analysis of X-ray Powder Diffraction (XPD, 28 ID) beamline at 500 mA, including Gas Bremsstrahlung (GB) and Synchrotron Radiation (SR).

36 MATERIALS SCIENCE↗
DOE OSTI2021

Tuning the 3D Printability and Thermomechanical Properties of Radiation Shields

Additive manufacturing, with its rapid advances in materials science, allows for researchers and companies to have the ability to create novel formulations and final parts that would have been difficult or near impossible to fabricate with traditional manufacturing methods. One such 3D printing technology, direct ink writing, is especially advantageous in fields requiring customizable parts with high amounts of functional fillers. Nuclear technology is a prime example of a field that necessitates new material design with regard to unique parts that also provide radiation shielding. Indeed, much effort has been focused on developing new rigid radiation shielding components, but DIW remains a less explored technology with a lot of potential for nuclear applications. In this study, DIW formulations that can behave as radiation shields were developed and were printed with varying amounts of porosity to tune the thermomechanical performance.

36 MATERIALS SCIENCE↗