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Results for “solidification”

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.

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At least 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

Dual solidification process of BN-350 liquid radioactive waste using high technology polymers and newly designed encapsulation techniques - 15198

Application of high technology polymers no.910 and no.960 manufactured by NOCHAR, USA, for treatment of liquid radioactive waste (LRW) have demonstrated good results at test sites worldwide. At the BN-350 site (Aktau, Kazakhstan), the tests were conducted successfully with contaminated oil, alkaline and salt containing LRW. This paper represents the results of immobilization of NOCHAR polymers, saturated with LRW, into solid matrix to comply with Kazakhstan regulatory requirements for long term storage and/or disposal. (authors)

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

Solidification technology for organic liquid waste combined with solid materials from Cernavoda NPP, Romania - 16453

Canadian Deuterium Uranium (CANDU{sup R}) reactor designs were initially developed in the late 1950's and 1960's by the Atomic Energy of Canada Limited (AECL) in partnership with Ontario Power Generation. CANDU{sup R} 6 reactors are Pressurized Heavy Water Reactors (PHWRs), with an integrated containment system and are designed as either multi or single unit systems. Two single CANDU 6 systems are currently operating at Cernavoda with an additional two units expected to be brought online in the near future. The radioactive waste produced by the plant is currently stored in a waste interim storage facility located on-site. The main sources of radioactive waste in a CANDU plant are: - Primary Heat Transport (PHT) systems, - Moderator systems, - Other sources of radionuclides. The radioactive waste management system at Cernavoda Nuclear Power Plant (NPP) was designed to maintain acceptable levels of safety for workers and to protect human health and the environment from exposure to unacceptable levels of radiation. During the operation of the Cernavoda NPP, a series of waste streams have been generated for waste treatment purposes. One important waste stream is the combination of solid materials and liquid organic waste, creating flammable solids. Flammable solids represent solid materials, such as cloth, plastic, contaminated with oil containing gamma nuclides and H-3 from maintenance activities. This paper explores a method to solve the problem of liquid residues on solid materials by the application of absorbent materials. The existence of liquid residues on solid materials is a common problem at nuclear power stations globally. The primary issue centers on an effective method of eliminating the liquid to allow for the final acceptance and disposal of the solid waste by regulators. (authors)

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

The impact of oxygen precipitation on dislocation generation at small angle grain boundaries during seed‐assisted directional solidification of silicon

We have investigated the source of dislocations generated during growth and subsequent cooling of quasi‐monocrystalline silicon. Bi‐crystals of silicon separated by ∼5.2° tilt small angle grain boundary have been directionally solidified at two different pulling rates, i.e., 3 and 13 μm s −1 . We observe higher density of grain boundary‐associated dislocations at the ingot pulled at a lower rate. This observation is explained by the impact of oxygen precipitation behavior at the grain boundary.

Autruffe, Antoine↗
DOE OSTI2019

Giant enhancement of the magnetocaloric response in Ni–Co–Mn–Ti by rapid solidification

Magnetocaloric refrigeration is a solid-state cooling approach that assures high energy efficiency and low environmental impact. It remains uncompetitive with conventional vapor-compression technologies due to lack of high-performing materials that exhibit large magnetocaloric effects in low magnetic fields. In this work we report a game-changing enhancement of the magnetocaloric response in a transition-metal-based Ni–Co–Mn–Ti. Mechanically and chemically stable rapidly solidified ribbons exhibit magnetic entropy changes as high as ~27J·kg –1 K –1 for a moderate field change of 2T, comparable to or larger than the best known materials for near-room temperature applications. The ribbons can be easily manufactured in large quantities and the transition temperature can be adjusted by varying Co concentration.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Location specific solidification microstructure control in electron beam melting of Ti-6Al-4V

Relationships between prior beta grain size in solidified Ti-6Al-4V and melting process parameters in the Electron Beam Melting (EBM) process are investigated. Samples are built by varying a machine-dependent proprietary speed function to cover the process space. Optical microscopy is used to measure prior beta grain widths and assess the number of prior beta grains present in a melt pool in the raster region of the build. Despite the complicated evolution of beta grain sizes, the beta grain width scales with melt pool width. The resulting understanding of the relationship between primary machine variables and prior beta grain widths is a key step toward enabling the location specific control of as-built microstructure in the EBM process. Control of grain width in separate specimens and within a single specimen is demonstrated.

42 ENGINEERING↗