SEARCH · Engineering Papers
Results for “SI”
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.
Iodine capture with mechanically robust heat-treated Ag-Al-Si-O xerogel sorbents
Silver-loaded heat-treated aluminosilicate xerogels (Ag-HTX) were evaluated as sorbents for iodine [I2(g)] capture. The heat treatment step was performed to help increase the mechanical integrity of the gels. The synthesized xerogels were characterized using powder X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, Brunauer-Emmett-Teller analysis, gravimetric iodine loading, nanoindentation, and dynamic mechanical analysis. The structural and chemical analyses of Ag-HTX showed uniform distribution of Ag throughout the gel network after Ag-exchange. After I2(g) capture, the AgI crystallites were observed in the sorbent verifying chemisorption as the iodine capture mechanism. Iodine loading of this xerogel was 0.43 g g-1 at 150°C over 1 d and 0.52 g g-1 at 22°C over 33 d. The specific surface area of Ag-HTX was 202 m2 g-1 and decreased to 87 m2 g-1 after iodine loading. The hardness of the heat-treated xerogel was 160 times higher than heat-treated aerogel of the same composition. The heat-treatment process increased the modulus value to 40.77 MPa from 6.99 MPa of as-made xerogel, demonstrating the need for this added step in the synthesis process. These results show that Ag-HTX is a promising sorbent for I2(g) capture with good loading capacity and mechanical stability.
In situ characterization of tensile behavior of laser rapid solidified Al–Si heterogeneous microstructures
Not provided.
Axiotaxy and epitaxial textures in C54-TiSi2 films on Si(0 0 1) and Si(1 1 1) substrates
Explore the source record for details and available documents.
Low-lying resonances in Si 26 relevant for the determination of the astrophysical Al 25 ( p , γ ) Si 26 reaction rate
Not Available
Computational generation of voids in a -Si and a -Si:H by cavitation at low density
Not Available
Loss Analysis and Performance Optimization Pathways of 729-mV Voc Si Solar Cells with Poly-Si on Locally-Etched Dielectric Passivating Contacts
In this article, the loss analysis of silicon solar cells with polysilicon on locally-etched dielectric passivating contacts with Voc=729.0 mV and efficiency=22.6% has been presented. Experimentally, nano-pinholes were introduced in SiO x (2.2 nm) and SiO x /SiN y (2.2 nm/8nm) stack using metal-assisted chemical etching (MACE). SunSolve and Quokka3 were used to simulate the experimental solar cell and investigate the optical and electrical power losses. Simulations suggest maximum power loss occurs due to recombination and resistive losses in the bulk (~0.76 mW/cm2) followed by power loss due to rear contact recombination (~0.35 mW/cm2). Recombination at the front surface also contributes to 0.24 mW/cm2. The effect of improving the bulk lifetime and lowering the recombination current density at the rear side on Voc, FF and hence, efficiency has been investigated. Further, advanced structures have been proposed to minimize recombination and parasitic absorption to achieve higher Voc and Jsc of the solar cells with locally-etched dielectric passivating contacts.
Quantum Transport Simulations for Si:P δ-layer Tunnel Junctions
Abstract not provided.
Laser beam directed energy deposition of high-Si content Fe-Si soft magnetic alloys
Explore the source record for details and available documents.
Materials Data on Si by Materials Project
Si is Clathrate-like structured and crystallizes in the tetragonal P4_2/nmc space group. The structure is three-dimensional. there are ten inequivalent Si sites. In the first Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are three shorter (2.36 Å) and one longer (2.38 Å) Si–Si bond lengths. In the second Si site, Si is bonded to four Si atoms to form a mixture of edge and corner-sharing SiSi4 tetrahedra. There are a spread of Si–Si bond distances ranging from 2.36–2.44 Å. In the third Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are one shorter (2.33 Å) and one longer (2.36 Å) Si–Si bond lengths. In the fourth Si site, Si is bonded to four Si atoms to form a mixture of edge and corner-sharing SiSi4 trigonal pyramids. There are a spread of Si–Si bond distances ranging from 2.31–2.36 Å. In the fifth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. The Si–Si bond length is 2.65 Å. In the sixth Si site, Si is bonded to four equivalent Si atoms to form corner-sharing SiSi4 tetrahedra. In the seventh Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are one shorter (2.40 Å) and one longer (2.48 Å) Si–Si bond lengths. In the eighth Si site, Si is bonded to four Si atoms to form a mixture of distorted edge and corner-sharing SiSi4 trigonal pyramids. The Si–Si bond length is 2.39 Å. In the ninth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are one shorter (2.41 Å) and one longer (2.43 Å) Si–Si bond lengths. In the tenth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra.
Materials Data on Si by Materials Project
Si is Clathrate-like structured and crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are nine inequivalent Si sites. In the first Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are a spread of Si–Si bond distances ranging from 2.35–2.40 Å. In the second Si site, Si is bonded to four Si atoms to form a mixture of edge and corner-sharing SiSi4 tetrahedra. There are a spread of Si–Si bond distances ranging from 2.33–2.39 Å. In the third Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are one shorter (2.33 Å) and three longer (2.35 Å) Si–Si bond lengths. In the fourth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are a spread of Si–Si bond distances ranging from 2.38–2.48 Å. In the fifth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. The Si–Si bond length is 2.38 Å. In the sixth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. Both Si–Si bond lengths are 2.32 Å. In the seventh Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. The Si–Si bond length is 2.41 Å. In the eighth Si site, Si is bonded to four Si atoms to form a mixture of edge and corner-sharing SiSi4 tetrahedra. In the ninth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra.
Materials Data on Si by Materials Project
Si is alpha Samarium structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are eight inequivalent Si sites. In the first Si site, Si is bonded to twelve Si atoms to form a mixture of corner, edge, and face-sharing SiSi12 cuboctahedra. There are six shorter (2.69 Å) and six longer (2.76 Å) Si–Si bond lengths. In the second Si site, Si is bonded to twelve Si atoms to form a mixture of corner, edge, and face-sharing SiSi12 cuboctahedra. There are a spread of Si–Si bond distances ranging from 2.69–2.77 Å. In the third Si site, Si is bonded to twelve Si atoms to form a mixture of corner, edge, and face-sharing SiSi12 cuboctahedra. All Si–Si bond lengths are 2.69 Å. In the fourth Si site, Si is bonded to twelve Si atoms to form SiSi12 cuboctahedra that share corners with fifteen SiSi16 cuboctahedra, edges with twenty-one SiSi16 cuboctahedra, and faces with nineteen SiSi12 cuboctahedra. There are a spread of Si–Si bond distances ranging from 2.69–2.77 Å. In the fifth Si site, Si is bonded to twelve Si atoms to form a mixture of corner, edge, and face-sharing SiSi12 cuboctahedra. There are six shorter (2.69 Å) and three longer (2.76 Å) Si–Si bond lengths. In the sixth Si site, Si is bonded to twelve Si atoms to form SiSi12 cuboctahedra that share corners with twenty-three SiSi16 cuboctahedra, edges with sixteen SiSi16 cuboctahedra, and faces with twenty-three SiSi12 cuboctahedra. There are six shorter (2.69 Å) and three longer (2.76 Å) Si–Si bond lengths. In the seventh Si site, Si is bonded to twelve Si atoms to form SiSi12 cuboctahedra that share corners with twenty SiSi16 cuboctahedra, edges with nineteen SiSi12 cuboctahedra, and faces with twenty-two SiSi12 cuboctahedra. There are six shorter (2.69 Å) and three longer (2.77 Å) Si–Si bond lengths. In the eighth Si site, Si is bonded to sixteen Si atoms to form SiSi16 cuboctahedra that share corners with twenty-five SiSi12 cuboctahedra, edges with twenty-one SiSi16 cuboctahedra, and faces with thirty-five SiSi16 cuboctahedra. There are a spread of Si–Si bond distances ranging from 2.69–5.37 Å.
Materials Data on Si by Materials Project
Si crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Si sites. In the first Si site, Si is bonded in a distorted pentagonal planar geometry to five Si atoms. There are a spread of Si–Si bond distances ranging from 2.34–2.67 Å. In the second Si site, Si is bonded in a 4-coordinate geometry to four Si atoms. There are a spread of Si–Si bond distances ranging from 2.41–2.58 Å. In the third Si site, Si is bonded in a tetrahedral geometry to four Si atoms. There are a spread of Si–Si bond distances ranging from 2.36–2.39 Å. In the fourth Si site, Si is bonded in a 4-coordinate geometry to four Si atoms. There are one shorter (2.39 Å) and one longer (2.41 Å) Si–Si bond lengths. In the fifth Si site, Si is bonded in a 4-coordinate geometry to four Si atoms. The Si–Si bond length is 2.44 Å. In the sixth Si site, Si is bonded in a 5-coordinate geometry to five Si atoms. There are one shorter (2.37 Å) and one longer (2.78 Å) Si–Si bond lengths. In the seventh Si site, Si is bonded in a 3-coordinate geometry to five Si atoms. The Si–Si bond length is 2.76 Å. In the eighth Si site, Si is bonded in a 4-coordinate geometry to five Si atoms.
Materials Data on Si by Materials Project
Si is Clathrate-like structured and crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. there are eight inequivalent Si sites. In the first Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are a spread of Si–Si bond distances ranging from 2.34–2.41 Å. In the second Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are a spread of Si–Si bond distances ranging from 2.32–2.37 Å. In the third Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. The Si–Si bond length is 2.31 Å. In the fourth Si site, Si is bonded to four Si atoms to form a mixture of corner and edge-sharing SiSi4 tetrahedra. There are a spread of Si–Si bond distances ranging from 2.41–2.46 Å. In the fifth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. The Si–Si bond length is 2.31 Å. In the sixth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. The Si–Si bond length is 2.33 Å. In the seventh Si site, Si is bonded to four Si atoms to form a mixture of distorted corner and edge-sharing SiSi4 tetrahedra. There are one shorter (2.41 Å) and two longer (2.46 Å) Si–Si bond lengths. In the eighth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra.
Materials Data on Si by Materials Project
Si is Clathrate-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are seven inequivalent Si sites. In the first Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are a spread of Si–Si bond distances ranging from 2.37–2.40 Å. In the second Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. There are one shorter (2.34 Å) and one longer (2.37 Å) Si–Si bond lengths. In the third Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. All Si–Si bond lengths are 2.37 Å. In the fourth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. The Si–Si bond length is 2.33 Å. In the fifth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. The Si–Si bond length is 2.40 Å. In the sixth Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra. Both Si–Si bond lengths are 2.37 Å. In the seventh Si site, Si is bonded to four Si atoms to form corner-sharing SiSi4 tetrahedra.