Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “H3S”

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.

11 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1990

The identification of H3S(+) with the ion of mass per charge (m/q) 35 observed in the coma of Comet Halley

A sharp peak in the mass spectrum at 35 amu is observed by the heavy ion analyzer on board the Giotto spacecraft just inside the ionopause. This peak is identified with H3S(+) and it is argued that the dominant source of its likely parent molecule (H2S) is the observed distributed source of circumnuclear dust, rather than the central nucleus. In this case, the total production rate of H2S is more than about 0.5 percent that of the dominant cometary molecule H2O.

Marconi, M. L.↗
DOE OSTI2020

Materials Data on H3S by Materials Project

SH3 is High-temperature superconductor structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two SH3 clusters. there are two inequivalent H+0.33+ sites. In the first H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one S1- atom. The H–S bond length is 1.48 Å. In the second H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one S1- atom. The H–S bond length is 1.41 Å. S1- is bonded in a distorted T-shaped geometry to three H+0.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H3S by Materials Project

SH3 is High-temperature superconductor structured and crystallizes in the cubic Im-3m space group. The structure is three-dimensional and consists of two SH3 frameworks. H+0.33+ is bonded in a linear geometry to two equivalent S1- atoms. Both H–S bond lengths are 1.82 Å. S1- is bonded to six equivalent H+0.33+ atoms to form corner-sharing SH6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H3S by Materials Project

SH3 is High-temperature superconductor structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two SH3 clusters. H+0.33+ is bonded in a single-bond geometry to one S1- atom. The H–S bond length is 1.45 Å. S1- is bonded in a distorted T-shaped geometry to three equivalent H+0.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H3S by Materials Project

SH3 crystallizes in the orthorhombic Cccm space group. The structure is one-dimensional and consists of eight hydrogen molecules and eight H2S ribbons oriented in the (0, 0, 1) direction. In each H2S ribbon, there are three inequivalent H+0.33+ sites. In the first H+0.33+ site, H+0.33+ is bonded in a linear geometry to two S1- atoms. There is one shorter (1.66 Å) and one longer (1.68 Å) H–S bond length. In the second H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one S1- atom. The H–S bond length is 1.36 Å. In the third H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one S1- atom. The H–S bond length is 1.35 Å. There are two inequivalent S1- sites. In the first S1- site, S1- is bonded in a distorted trigonal non-coplanar geometry to three H+0.33+ atoms. In the second S1- site, S1- is bonded in a distorted trigonal non-coplanar geometry to three H+0.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H3S by Materials Project

SH3 is Khatyrkite-derived structured and crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of four hydrogen molecules and eight hydrogen sulfide molecules.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Dilute carbon in H3S under pressure

Abstract Recently, room temperature superconductivity was measured in a carbonaceous sulfur hydride material whose identity remains unknown. Herein, first-principles calculations are performed to provide a chemical basis for structural candidates derived by doping H 3 S with low levels of carbon. Pressure stabilizes unusual bonding configurations about the carbon atoms, which can be six-fold coordinated as CH 6 entities within the cubic H 3 S framework, or four-fold coordinated as methane intercalated into the H-S lattice, with or without an additional hydrogen in the framework. The doping breaks degenerate bands, lowering the density of states at the Fermi level ( N F ), and localizing electrons in C-H bonds. Low levels of CH 4 doping do not increase N F to values as high as those calculated for $$Im\bar{3}m$$ I m 3 ¯ m -H 3 S, but they can yield a larger logarithmic average phonon frequency, and an electron–phonon coupling parameter comparable to that of R 3 m -H 3 S. The implications of carbon doping on the superconducting properties are discussed.

36 MATERIALS SCIENCE↗
NASA NTRS1994

Methanol and hydrogen sulfide in comet P/Halley

The Neutral Mass Spectrometer on the Giotto spacecraft measured the gas and ion composition in the coma of comet P/Halley. A detailed model of the ion chemistry inside the contact surface located at 4660 km is used to interpret the measured ion desnity profiles in the 32 to 35 amu/e mass range. The masses 33 and 35 amu/e are dominated by the protonated methanol and hydrogen sulfide ions CH3OH2(+) and H3S(+). Both profiles are essentially compatible with CH3OH and H2S originating from the nucleus only. The production rates relative to water are Y(CH3OH) = Q(CH3OH)/Q(H2O) = 1.7% and Y(H2S) = 0.41%. Our Y(CH3OH) agrees well with a determination from IR spectra obtained about 6 weeks after the Giotto encounter with P/Halley. In 7 other comets IR and microwave observations give Y(CH3OH) values between about 0.7 and 6%, indicating that the methanol abundance shows a strong variability from comet to comet. In three other comets Y(H2S) values between 0.2 and 0.5% have been reported. In addition to H2S(+), only ions containing minor isotopes of H, C, O and S contribute to mass 34 amu/e (e.g. (34)S(+), (13)CH3OH2(+), CH4DO(+)). These contributions can be calculated from the measured densities of the ions containing the major isotopes and the H2S(+) contribution from the measured H3S(+) density. From mass 34 amu/e we can also derive an upper limit of 1% for the abundance of deuterated methanol. This limit is at most marginally compatible with a direct interstellar origin of the CH3OH in P/Halley as the measured interstellar abundance of deuterated methanol is 1 to 6%.

Eberhardt, P.↗
DOE OSTI2023

The molecular basis of the neutralization breadth of the RBD-specific antibody CoV11

SARS-CoV-2, the virus behind the COVID-19 pandemic, has changed over time to the extent that the current virus is substantially different from what originally led to the pandemic in 2019–2020. Viral variants have modified the severity and transmissibility of the disease and continue do so. How much of this change is due to viral fitness versus a response to immune pressure is hard to define. One class of antibodies that continues to afford some level of protection from emerging variants are those that closely overlap the binding site for angiotensin-converting enzyme 2 (ACE2) on the receptor binding domain (RBD). Some members of this class that were identified early in the course of the pandemic arose from the VH 3-53 germline gene (IGHV3-53*01) and had short heavy chain complementarity-determining region 3s (CDR H3s). Here, we describe the molecular basis of the SARS-CoV-2 RBD recognition by the anti-RBD monoclonal antibody CoV11 isolated early in the COVID-19 pandemic and show how its unique mode of binding the RBD determines its neutralization breadth. CoV11 utilizes a heavy chain VH 3-53 and a light chain VK 3-20 germline sequence to bind to the RBD. Two of CoV11’s four heavy chain changes from the VH 3-53 germline sequence, $Thr^{28}_{FWRH1}$ to Ile and $Ser^{31}_{CDRH1}$ to Arg, and some unique features in its CDR H3 increase its affinity to the RBD, while the four light chain changes from the VK 3-20 germline sequence sit outside of the RBD binding site. Antibodies of this type can retain significant affinity and neutralization potency against variants of concern (VOCs) that have diverged significantly from original virus lineage such as the prevalent omicron variant. We also discuss the mechanism by which VH 3-53 encoded antibodies recognize spike antigen and show how minimal changes to their sequence, their choice of light chain, and their mode of binding influence their affinity and impact their neutralization breadth.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

Structures of HIV-1 Neutralizing Antibody 10E8 Delineate the Mechanistic Basis of Its Multi-Peak Behavior on Size-Exclusion Chromatography

Antibody 10E8 is capable of effectively neutralizing HIV through its recognition of the membrane-proximal external region (MPER), and a suitably optimized version of 10E8 might have utility in HIV therapy and prophylaxis. However, 10E8 displays a three-peak profile on size-exclusion chromatography (SEC), complicating its manufacture. Here we show cis-trans conformational isomerization of the Tyr-Pro-Pro (YPP) motif in the heavy chain 3rd complementarity-determining region (CDR H3) of antibody 10E8 to be the mechanistic basis of its multipeak behavior. We observed 10E8 to undergo slow conformational isomerization and delineate a mechanistic explanation for effective comodifiers that were able to resolve its SEC heterogeneity and to allow an evaluation of the critical quality attribute of aggregation. We determined crystal structures of single and double alanine mutants of a key di-proline motif and of a light chain variant, revealing alternative conformations of the CDR H3. We also replicated both multi-peak and delayed SEC behavior with MPER-antibodies 4E10 and VRC42, by introducing a Tyr-Pro (YP) motif into their CDR H3s. Our results show how a conformationally dynamic CDR H3 can provide the requisite structural plasticity needed for a highly hydrophobic paratope to recognize its membrane-proximal epitope.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2024

On creep of trapped flux near T c in MgB 2 and CaKFe 4 As 4

Here, we present flux creep data taken at different temperatures on single crystals of known, ambient pressure, superconductors, CaKFe 4 As 4 and MgB 2 , taken using the protocol that is common for trapped flux measurements. Using our results, we show that the time dependence of the magnetic moment in H 3 S is remarkably similar to the magnetization relaxation rates observed in established superconductors at ambient pressure, where in the latter cases this can be unambiguously assigned to flux creep.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗