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At least 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on CePa3 by Materials Project

Pa3Ce is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Pa is bonded to eight equivalent Pa and four equivalent Ce atoms to form PaCe4Pa8 cuboctahedra that share corners with twelve equivalent PaCe4Pa8 cuboctahedra, edges with eight equivalent CePa12 cuboctahedra, edges with sixteen equivalent PaCe4Pa8 cuboctahedra, faces with four equivalent CePa12 cuboctahedra, and faces with fourteen equivalent PaCe4Pa8 cuboctahedra. All Pa–Pa bond lengths are 3.29 Å. All Pa–Ce bond lengths are 3.29 Å. Ce is bonded to twelve equivalent Pa atoms to form CePa12 cuboctahedra that share corners with twelve equivalent CePa12 cuboctahedra, edges with twenty-four equivalent PaCe4Pa8 cuboctahedra, faces with six equivalent CePa12 cuboctahedra, and faces with twelve equivalent PaCe4Pa8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pa3Hg by Materials Project

Pa3Hg is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Pa is bonded to eight equivalent Pa and four equivalent Hg atoms to form distorted PaPa8Hg4 cuboctahedra that share corners with twelve equivalent PaPa8Hg4 cuboctahedra, edges with eight equivalent HgPa12 cuboctahedra, edges with sixteen equivalent PaPa8Hg4 cuboctahedra, faces with four equivalent HgPa12 cuboctahedra, and faces with fourteen equivalent PaPa8Hg4 cuboctahedra. All Pa–Pa bond lengths are 3.27 Å. All Pa–Hg bond lengths are 3.27 Å. Hg is bonded to twelve equivalent Pa atoms to form HgPa12 cuboctahedra that share corners with twelve equivalent HgPa12 cuboctahedra, edges with twenty-four equivalent PaPa8Hg4 cuboctahedra, faces with six equivalent HgPa12 cuboctahedra, and faces with twelve equivalent PaPa8Hg4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on DyPa by Materials Project

PaDy crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Pa is bonded to six equivalent Pa and six equivalent Dy atoms to form PaDy6Pa6 cuboctahedra that share corners with eighteen equivalent PaDy6Pa6 cuboctahedra, edges with six equivalent PaDy6Pa6 cuboctahedra, edges with twelve equivalent DyDy6Pa6 cuboctahedra, faces with eight equivalent PaDy6Pa6 cuboctahedra, and faces with twelve equivalent DyDy6Pa6 cuboctahedra. All Pa–Pa bond lengths are 3.30 Å. All Pa–Dy bond lengths are 3.46 Å. Dy is bonded to six equivalent Pa and six equivalent Dy atoms to form DyDy6Pa6 cuboctahedra that share corners with eighteen equivalent DyDy6Pa6 cuboctahedra, edges with six equivalent DyDy6Pa6 cuboctahedra, edges with twelve equivalent PaDy6Pa6 cuboctahedra, faces with eight equivalent DyDy6Pa6 cuboctahedra, and faces with twelve equivalent PaDy6Pa6 cuboctahedra. All Dy–Dy bond lengths are 3.30 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PaTa by Materials Project

PaTa is Magnesium-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Pa is bonded to six equivalent Pa and six equivalent Ta atoms to form PaPa6Ta6 cuboctahedra that share corners with eighteen equivalent PaPa6Ta6 cuboctahedra, edges with six equivalent PaPa6Ta6 cuboctahedra, edges with twelve equivalent TaPa6Ta6 cuboctahedra, faces with eight equivalent PaPa6Ta6 cuboctahedra, and faces with twelve equivalent TaPa6Ta6 cuboctahedra. All Pa–Pa bond lengths are 3.07 Å. All Pa–Ta bond lengths are 3.22 Å. Ta is bonded to six equivalent Pa and six equivalent Ta atoms to form TaPa6Ta6 cuboctahedra that share corners with eighteen equivalent TaPa6Ta6 cuboctahedra, edges with six equivalent TaPa6Ta6 cuboctahedra, edges with twelve equivalent PaPa6Ta6 cuboctahedra, faces with eight equivalent TaPa6Ta6 cuboctahedra, and faces with twelve equivalent PaPa6Ta6 cuboctahedra. All Ta–Ta bond lengths are 3.07 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SmPa by Materials Project

PaSm is Magnesium-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Pa is bonded to six equivalent Pa and six equivalent Sm atoms to form PaSm6Pa6 cuboctahedra that share corners with eighteen equivalent PaSm6Pa6 cuboctahedra, edges with six equivalent PaSm6Pa6 cuboctahedra, edges with twelve equivalent SmSm6Pa6 cuboctahedra, faces with eight equivalent PaSm6Pa6 cuboctahedra, and faces with twelve equivalent SmSm6Pa6 cuboctahedra. All Pa–Pa bond lengths are 3.31 Å. All Pa–Sm bond lengths are 3.53 Å. Sm is bonded to six equivalent Pa and six equivalent Sm atoms to form SmSm6Pa6 cuboctahedra that share corners with eighteen equivalent SmSm6Pa6 cuboctahedra, edges with six equivalent SmSm6Pa6 cuboctahedra, edges with twelve equivalent PaSm6Pa6 cuboctahedra, faces with eight equivalent SmSm6Pa6 cuboctahedra, and faces with twelve equivalent PaSm6Pa6 cuboctahedra. All Sm–Sm bond lengths are 3.31 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PaCd by Materials Project

PaCd is Magnesium-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Pa is bonded to six equivalent Pa and six equivalent Cd atoms to form PaPa6Cd6 cuboctahedra that share corners with eighteen equivalent PaPa6Cd6 cuboctahedra, edges with six equivalent PaPa6Cd6 cuboctahedra, edges with twelve equivalent CdPa6Cd6 cuboctahedra, faces with eight equivalent PaPa6Cd6 cuboctahedra, and faces with twelve equivalent CdPa6Cd6 cuboctahedra. All Pa–Pa bond lengths are 3.12 Å. All Pa–Cd bond lengths are 3.40 Å. Cd is bonded to six equivalent Pa and six equivalent Cd atoms to form CdPa6Cd6 cuboctahedra that share corners with eighteen equivalent CdPa6Cd6 cuboctahedra, edges with six equivalent CdPa6Cd6 cuboctahedra, edges with twelve equivalent PaPa6Cd6 cuboctahedra, faces with eight equivalent CdPa6Cd6 cuboctahedra, and faces with twelve equivalent PaPa6Cd6 cuboctahedra. All Cd–Cd bond lengths are 3.12 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pa3H by Materials Project

Pa3H is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Pa is bonded to eight equivalent Pa and four equivalent H atoms to form distorted PaPa8H4 cuboctahedra that share corners with twelve equivalent PaPa8H4 cuboctahedra, edges with eight equivalent HPa12 cuboctahedra, edges with sixteen equivalent PaPa8H4 cuboctahedra, faces with four equivalent HPa12 cuboctahedra, and faces with fourteen equivalent PaPa8H4 cuboctahedra. All Pa–Pa bond lengths are 3.03 Å. All Pa–H bond lengths are 3.03 Å. H is bonded to twelve equivalent Pa atoms to form HPa12 cuboctahedra that share corners with twelve equivalent HPa12 cuboctahedra, edges with twenty-four equivalent PaPa8H4 cuboctahedra, faces with six equivalent HPa12 cuboctahedra, and faces with twelve equivalent PaPa8H4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on DyPa3 by Materials Project

Pa3Dy is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Pa is bonded to eight equivalent Pa and four equivalent Dy atoms to form PaDy4Pa8 cuboctahedra that share corners with twelve equivalent PaDy4Pa8 cuboctahedra, edges with eight equivalent DyPa12 cuboctahedra, edges with sixteen equivalent PaDy4Pa8 cuboctahedra, faces with four equivalent DyPa12 cuboctahedra, and faces with fourteen equivalent PaDy4Pa8 cuboctahedra. All Pa–Pa bond lengths are 3.33 Å. All Pa–Dy bond lengths are 3.33 Å. Dy is bonded to twelve equivalent Pa atoms to form DyPa12 cuboctahedra that share corners with twelve equivalent DyPa12 cuboctahedra, edges with twenty-four equivalent PaDy4Pa8 cuboctahedra, faces with six equivalent DyPa12 cuboctahedra, and faces with twelve equivalent PaDy4Pa8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pa3Al by Materials Project

Pa3Al is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Pa is bonded to eight equivalent Pa and four equivalent Al atoms to form PaPa8Al4 cuboctahedra that share corners with twelve equivalent PaPa8Al4 cuboctahedra, edges with eight equivalent AlPa12 cuboctahedra, edges with sixteen equivalent PaPa8Al4 cuboctahedra, faces with four equivalent AlPa12 cuboctahedra, and faces with fourteen equivalent PaPa8Al4 cuboctahedra. All Pa–Pa bond lengths are 3.20 Å. All Pa–Al bond lengths are 3.20 Å. Al is bonded to twelve equivalent Pa atoms to form AlPa12 cuboctahedra that share corners with twelve equivalent AlPa12 cuboctahedra, edges with twenty-four equivalent PaPa8Al4 cuboctahedra, faces with six equivalent AlPa12 cuboctahedra, and faces with twelve equivalent PaPa8Al4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ErPa3 by Materials Project

Pa3Er is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Pa is bonded to eight equivalent Pa and four equivalent Er atoms to form PaEr4Pa8 cuboctahedra that share corners with twelve equivalent PaEr4Pa8 cuboctahedra, edges with eight equivalent ErPa12 cuboctahedra, edges with sixteen equivalent PaEr4Pa8 cuboctahedra, faces with four equivalent ErPa12 cuboctahedra, and faces with fourteen equivalent PaEr4Pa8 cuboctahedra. All Pa–Pa bond lengths are 3.33 Å. All Pa–Er bond lengths are 3.33 Å. Er is bonded to twelve equivalent Pa atoms to form ErPa12 cuboctahedra that share corners with twelve equivalent ErPa12 cuboctahedra, edges with twenty-four equivalent PaEr4Pa8 cuboctahedra, faces with six equivalent ErPa12 cuboctahedra, and faces with twelve equivalent PaEr4Pa8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ThPa3 by Materials Project

Pa3Th is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Pa is bonded to eight equivalent Pa and four equivalent Th atoms to form PaTh4Pa8 cuboctahedra that share corners with twelve equivalent PaTh4Pa8 cuboctahedra, edges with eight equivalent ThPa12 cuboctahedra, edges with sixteen equivalent PaTh4Pa8 cuboctahedra, faces with four equivalent ThPa12 cuboctahedra, and faces with fourteen equivalent PaTh4Pa8 cuboctahedra. All Pa–Pa bond lengths are 3.35 Å. All Pa–Th bond lengths are 3.35 Å. Th is bonded to twelve equivalent Pa atoms to form ThPa12 cuboctahedra that share corners with twelve equivalent ThPa12 cuboctahedra, edges with twenty-four equivalent PaTh4Pa8 cuboctahedra, faces with six equivalent ThPa12 cuboctahedra, and faces with twelve equivalent PaTh4Pa8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YbPa3 by Materials Project

Pa3Yb is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Pa is bonded to eight equivalent Pa and four equivalent Yb atoms to form distorted PaYb4Pa8 cuboctahedra that share corners with twelve equivalent PaYb4Pa8 cuboctahedra, edges with eight equivalent YbPa12 cuboctahedra, edges with sixteen equivalent PaYb4Pa8 cuboctahedra, faces with four equivalent YbPa12 cuboctahedra, and faces with fourteen equivalent PaYb4Pa8 cuboctahedra. All Pa–Pa bond lengths are 3.30 Å. All Pa–Yb bond lengths are 3.30 Å. Yb is bonded to twelve equivalent Pa atoms to form YbPa12 cuboctahedra that share corners with twelve equivalent YbPa12 cuboctahedra, edges with twenty-four equivalent PaYb4Pa8 cuboctahedra, faces with six equivalent YbPa12 cuboctahedra, and faces with twelve equivalent PaYb4Pa8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TbPa by Materials Project

PaTb crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Pa is bonded to six equivalent Pa and six equivalent Tb atoms to form PaTb6Pa6 cuboctahedra that share corners with eighteen equivalent PaTb6Pa6 cuboctahedra, edges with six equivalent PaTb6Pa6 cuboctahedra, edges with twelve equivalent TbTb6Pa6 cuboctahedra, faces with eight equivalent PaTb6Pa6 cuboctahedra, and faces with twelve equivalent TbTb6Pa6 cuboctahedra. All Pa–Pa bond lengths are 3.30 Å. All Pa–Tb bond lengths are 3.48 Å. Tb is bonded to six equivalent Pa and six equivalent Tb atoms to form TbTb6Pa6 cuboctahedra that share corners with eighteen equivalent TbTb6Pa6 cuboctahedra, edges with six equivalent TbTb6Pa6 cuboctahedra, edges with twelve equivalent PaTb6Pa6 cuboctahedra, faces with eight equivalent TbTb6Pa6 cuboctahedra, and faces with twelve equivalent PaTb6Pa6 cuboctahedra. All Tb–Tb bond lengths are 3.30 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PmPa by Materials Project

PaPm crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Pa is bonded to six equivalent Pa and six equivalent Pm atoms to form PaPm6Pa6 cuboctahedra that share corners with eighteen equivalent PaPm6Pa6 cuboctahedra, edges with six equivalent PaPm6Pa6 cuboctahedra, edges with twelve equivalent PmPm6Pa6 cuboctahedra, faces with eight equivalent PaPm6Pa6 cuboctahedra, and faces with twelve equivalent PmPm6Pa6 cuboctahedra. All Pa–Pa bond lengths are 3.32 Å. All Pa–Pm bond lengths are 3.54 Å. Pm is bonded to six equivalent Pa and six equivalent Pm atoms to form PmPm6Pa6 cuboctahedra that share corners with eighteen equivalent PmPm6Pa6 cuboctahedra, edges with six equivalent PmPm6Pa6 cuboctahedra, edges with twelve equivalent PaPm6Pa6 cuboctahedra, faces with eight equivalent PmPm6Pa6 cuboctahedra, and faces with twelve equivalent PaPm6Pa6 cuboctahedra. All Pm–Pm bond lengths are 3.32 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pa3Cd by Materials Project

Pa3Cd is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Pa is bonded to eight equivalent Pa and four equivalent Cd atoms to form PaPa8Cd4 cuboctahedra that share corners with twelve equivalent PaPa8Cd4 cuboctahedra, edges with eight equivalent CdPa12 cuboctahedra, edges with sixteen equivalent PaPa8Cd4 cuboctahedra, faces with four equivalent CdPa12 cuboctahedra, and faces with fourteen equivalent PaPa8Cd4 cuboctahedra. All Pa–Pa bond lengths are 3.27 Å. All Pa–Cd bond lengths are 3.27 Å. Cd is bonded to twelve equivalent Pa atoms to form CdPa12 cuboctahedra that share corners with twelve equivalent CdPa12 cuboctahedra, edges with twenty-four equivalent PaPa8Cd4 cuboctahedra, faces with six equivalent CdPa12 cuboctahedra, and faces with twelve equivalent PaPa8Cd4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Grazing Incidence Wide-Angle X-ray Scattering of Water Adsorption in Polyamide Barrier Layers of Reverse Osmosis Membranes

To understand the relationship between the intermolecular structure of aromatic polyamide (PA) scaffold and the water molecules in the barrier layers of reverse osmosis (RO) membranes, a grazing incidence wide-angle X-ray scattering (GIWAXS) study was carried out on freestanding PA thin films at varying relative humidity (RH) conditions. The scattering results were analyzed by an interference scattering model, containing a phase factor between a PA chain and an adsorbed water molecule. This model yielded good fits to the GIWAXS profiles where the water adsorption was found to vary linearly with RH. Atomistic molecular dynamics (MD) simulations were also performed to complement the experimental study. Furthermore, the simulations revealed that a rapid condensation layer initially formed on the PA film surface, followed by the slow water molecule diffusion inside the PA membrane. Sparse adsorbed water, isolated in subnanopores of the PA film adjacent to the polar atoms, even in very low quantities, modifies the X-ray scattering. Atomistic simulations at the microscopic scale provide partial support for several X-ray scattering findings.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Convergent use of phosphatidic acid for hepatitis C virus and SARS-CoV-2 replication organelle formation

Double membrane vesicles (DMVs) serve as replication organelles of plus-strand RNA viruses such as hepatitis C virus (HCV) and SARS-CoV-2. Viral DMVs are morphologically analogous to DMVs formed during autophagy, but lipids driving their biogenesis are largely unknown. Here we show that production of the lipid phosphatidic acid (PA) by acylglycerolphosphate acyltransferase (AGPAT) 1 and 2 in the ER is important for DMV biogenesis in viral replication and autophagy. Using DMVs in HCV-replicating cells as model, we found that AGPATs are recruited to and critically contribute to HCV and SARS-CoV-2 replication and proper DMV formation. An intracellular PA sensor accumulated at viral DMV formation sites, consistent with elevated levels of PA in fractions of purified DMVs analyzed by lipidomics. Apart from AGPATs, PA is generated by alternative pathways and their pharmacological inhibition also impaired HCV and SARS-CoV-2 replication as well as formation of autophagosome-like DMVs. These data identify PA as host cell lipid involved in proper replication organelle formation by HCV and SARS-CoV-2, two phylogenetically disparate viruses causing very different diseases, i.e. chronic liver disease and COVID-19, respectively. Host-targeting therapy aiming at PA synthesis pathways might be suitable to attenuate replication of these viruses.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

Self-sorting in supramolecular assemblies

Supramolecular self-assembly enables living organisms to form highly functional hierarchical structures with individual components self-organized across multiple length scales. This has inspired work on multicomponent supramolecular materials to understand factors behind co-assembly versus self-sorting of molecules. We report here on a supramolecular system comprised of negatively charged peptide amphiphile (PA) molecules, in which only a tiny fraction of the molecules (0.7 mol%) were covalently conjugated to one of two different fluorophores, half to fluorescein isothiocyanate (FTIC) and the other half to tetramethylrhodamine (TAMRA). Confocal microscopy of the system revealed self-sorting of the two different fluorescent PA molecules, where TAMRA PA is concentrated in micron-scale domains while FITC PA remains dispersed throughout the sample. From Förster resonance energy transfer and fluorescence recovery experiments, we conclude that conjugation of the negatively charged FITC to PA significantly disrupts its co-assembly with the 99.3 mol% of unlabeled molecules, which are responsible for formation of micron-scale domains. Conversely, conjugation of the zwitterionic TAMRA causes no such disruption. Interestingly, this dissimilar behavior between FITC and TAMRA PA causes them to self-sort at large length scales in the supramolecular system, mediated not by specific interactions among the individual fluorophores but instead by their different propensities to co-assemble with the majority component. We also found that greater ionic strength in the aqueous environment of the system promotes mixing by lowering the electrostatic barriers involved in self-sorting. Furthermore, our results demonstrate great thermodynamic subtlety in the driving forces that mediate self-sorting versus co-assembly in supramolecular peptide assemblies.

36 MATERIALS SCIENCE↗