Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Be(HO)2”

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 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Ho(PPd)2 by Materials Project

Ho(PdP)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ho is bonded in a 8-coordinate geometry to eight equivalent Pd and eight equivalent P atoms. All Ho–Pd bond lengths are 3.21 Å. All Ho–P bond lengths are 3.09 Å. Pd is bonded to four equivalent Ho, four equivalent Pd, and four equivalent P atoms to form a mixture of distorted edge, corner, and face-sharing PdHo4P4Pd4 cuboctahedra. All Pd–Pd bond lengths are 2.89 Å. All Pd–P bond lengths are 2.47 Å. P is bonded in a 9-coordinate geometry to four equivalent Ho, four equivalent Pd, and one P atom. The P–P bond length is 2.19 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(SiIr)2 by Materials Project

Ho(IrSi)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ho is bonded in a 8-coordinate geometry to eight Ir and eight Si atoms. There are four shorter (3.13 Å) and four longer (3.25 Å) Ho–Ir bond lengths. There are four shorter (3.16 Å) and four longer (3.18 Å) Ho–Si bond lengths. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded to four equivalent Ho and four equivalent Si atoms to form distorted IrHo4Si4 tetrahedra that share corners with twelve equivalent SiHo4Ir4 tetrahedra, edges with two equivalent SiHo4Ir4 tetrahedra, edges with four equivalent IrHo4Si4 tetrahedra, and faces with four equivalent IrHo4Si4 tetrahedra. All Ir–Si bond lengths are 2.43 Å. In the second Ir site, Ir is bonded in a 9-coordinate geometry to four equivalent Ho and five Si atoms. There are one shorter (2.37 Å) and four longer (2.42 Å) Ir–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded to four equivalent Ho and four equivalent Ir atoms to form distorted SiHo4Ir4 tetrahedra that share corners with twelve equivalent IrHo4Si4 tetrahedra, edges with two equivalent IrHo4Si4 tetrahedra, edges with four equivalent SiHo4Ir4 tetrahedra, and faces with four equivalent SiHo4Ir4 tetrahedra. In the second Si site, Si is bonded in a 9-coordinate geometry to four equivalent Ho and five Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(Ni2P)2 by Materials Project

Ho(Ni2P)2 crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Ho is bonded in a 6-coordinate geometry to six equivalent P atoms. There are two shorter (2.79 Å) and four longer (2.83 Å) Ho–P bond lengths. Ni is bonded in a 3-coordinate geometry to three equivalent P atoms. There are two shorter (2.30 Å) and one longer (2.31 Å) Ni–P bond lengths. P is bonded in a 9-coordinate geometry to three equivalent Ho and six equivalent Ni atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(Al5Ru)2 by Materials Project

Ho(RuAl5)2 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Ho is bonded in a 10-coordinate geometry to four equivalent Ru and fourteen Al atoms. All Ho–Ru bond lengths are 3.47 Å. There are a spread of Ho–Al bond distances ranging from 3.15–3.35 Å. Ru is bonded in a 10-coordinate geometry to two equivalent Ho and ten Al atoms. There are a spread of Ru–Al bond distances ranging from 2.57–2.76 Å. There are five inequivalent Al sites. In the first Al site, Al is bonded in a 2-coordinate geometry to one Ho and two equivalent Ru atoms. In the second Al site, Al is bonded in a distorted linear geometry to two equivalent Ho and two equivalent Ru atoms. In the third Al site, Al is bonded in a 2-coordinate geometry to two equivalent Ho and two equivalent Ru atoms. In the fourth Al site, Al is bonded in a distorted bent 120 degrees geometry to one Ho and two equivalent Ru atoms. In the fifth Al site, Al is bonded in a 12-coordinate geometry to one Ho and two equivalent Ru atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(SiNi)2 by Materials Project

Ho(NiSi)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ho3+ is bonded in a distorted body-centered cubic geometry to eight equivalent Si4- atoms. All Ho–Si bond lengths are 3.04 Å. Ni+2.50+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing NiSi4 tetrahedra. All Ni–Si bond lengths are 2.30 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Ho3+, four equivalent Ni+2.50+, and one Si4- atom. The Si–Si bond length is 2.40 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(GeRu)2 by Materials Project

Ho(RuGe)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ho is bonded in a 8-coordinate geometry to eight equivalent Ru and eight equivalent Ge atoms. All Ho–Ru bond lengths are 3.26 Å. All Ho–Ge bond lengths are 3.28 Å. Ru is bonded in a 4-coordinate geometry to four equivalent Ho and four equivalent Ge atoms. All Ru–Ge bond lengths are 2.44 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Ho, four equivalent Ru, and one Ge atom. The Ge–Ge bond length is 2.56 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(GeRh)2 by Materials Project

Ho(RhGe)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ho is bonded in a 8-coordinate geometry to eight equivalent Rh and eight equivalent Ge atoms. All Ho–Rh bond lengths are 3.31 Å. All Ho–Ge bond lengths are 3.19 Å. Rh is bonded to four equivalent Ho and four equivalent Ge atoms to form a mixture of distorted corner, edge, and face-sharing RhHo4Ge4 tetrahedra. All Rh–Ge bond lengths are 2.46 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Ho, four equivalent Rh, and one Ge atom. The Ge–Ge bond length is 2.51 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(FeB)2 by Materials Project

Ho(FeB)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ho is bonded in a 8-coordinate geometry to eight equivalent Fe and eight equivalent B atoms. All Ho–Fe bond lengths are 2.94 Å. All Ho–B bond lengths are 2.94 Å. Fe is bonded in a 4-coordinate geometry to four equivalent Ho and four equivalent B atoms. All Fe–B bond lengths are 2.00 Å. B is bonded in a 4-coordinate geometry to four equivalent Ho and four equivalent Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(CuS)2 by Materials Project

Ho(CuS)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ho is bonded to six equivalent S atoms to form distorted HoS6 octahedra that share corners with twelve equivalent CuS4 tetrahedra, edges with six equivalent HoS6 octahedra, and edges with six equivalent CuS4 tetrahedra. All Ho–S bond lengths are 2.82 Å. Cu is bonded to four equivalent S atoms to form distorted CuS4 tetrahedra that share corners with six equivalent HoS6 octahedra, corners with six equivalent CuS4 tetrahedra, edges with three equivalent HoS6 octahedra, and edges with three equivalent CuS4 tetrahedra. The corner-sharing octahedra tilt angles range from 24–54°. There are three shorter (2.33 Å) and one longer (2.49 Å) Cu–S bond lengths. S is bonded in a 7-coordinate geometry to three equivalent Ho and four equivalent Cu atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(TiGa2)2 by Materials Project

Ho(TiGa2)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ho is bonded in a distorted square co-planar geometry to twelve Ga atoms. There are four shorter (2.89 Å) and eight longer (3.32 Å) Ho–Ga bond lengths. Ti is bonded in a 10-coordinate geometry to two equivalent Ti and eight Ga atoms. Both Ti–Ti bond lengths are 2.73 Å. All Ti–Ga bond lengths are 2.80 Å. There are eight inequivalent Ga sites. In the first Ga site, Ga is bonded in a 11-coordinate geometry to three equivalent Ho, four equivalent Ti, and four Ga atoms. There are two shorter (2.67 Å) and two longer (2.91 Å) Ga–Ga bond lengths. In the second Ga site, Ga is bonded in a 11-coordinate geometry to three equivalent Ho, four equivalent Ti, and four Ga atoms. There are two shorter (2.67 Å) and two longer (2.91 Å) Ga–Ga bond lengths. In the third Ga site, Ga is bonded in a 11-coordinate geometry to three equivalent Ho, four equivalent Ti, and four Ga atoms. Both Ga–Ga bond lengths are 2.91 Å. In the fourth Ga site, Ga is bonded in a 11-coordinate geometry to three equivalent Ho, four equivalent Ti, and four Ga atoms. Both Ga–Ga bond lengths are 2.91 Å. In the fifth Ga site, Ga is bonded in a 11-coordinate geometry to three equivalent Ho, four equivalent Ti, and four Ga atoms. Both Ga–Ga bond lengths are 2.67 Å. In the sixth Ga site, Ga is bonded in a 11-coordinate geometry to three equivalent Ho, four equivalent Ti, and four Ga atoms. Both Ga–Ga bond lengths are 2.67 Å. In the seventh Ga site, Ga is bonded in a 11-coordinate geometry to three equivalent Ho, four equivalent Ti, and four Ga atoms. In the eighth Ga site, Ga is bonded in a 11-coordinate geometry to three equivalent Ho, four equivalent Ti, and four Ga atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(Ni2As)2 by Materials Project

Ho(Ni2As)2 crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Ho is bonded to six equivalent As atoms to form a mixture of distorted corner and edge-sharing HoAs6 octahedra. The corner-sharing octahedral tilt angles are 40°. There are two shorter (2.89 Å) and four longer (2.91 Å) Ho–As bond lengths. Ni is bonded in a 3-coordinate geometry to three equivalent As atoms. All Ni–As bond lengths are 2.40 Å. As is bonded in a 9-coordinate geometry to three equivalent Ho and six equivalent Ni atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(Ge2Rh3)2 by Materials Project

Ho(Rh3Ge2)2 crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Ho is bonded to six equivalent Rh and six equivalent Ge atoms to form face-sharing HoGe6Rh6 cuboctahedra. All Ho–Rh bond lengths are 3.14 Å. All Ho–Ge bond lengths are 3.12 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 5-coordinate geometry to five Ge atoms. There are one shorter (2.51 Å) and four longer (2.56 Å) Rh–Ge bond lengths. In the second Rh site, Rh is bonded in a 6-coordinate geometry to two equivalent Ho and four Ge atoms. There are two shorter (2.47 Å) and two longer (2.56 Å) Rh–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 8-coordinate geometry to two equivalent Ho and six Rh atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to nine Rh atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(NiB)2 by Materials Project

Ho(NiB)2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Ho3+ is bonded in a 6-coordinate geometry to six equivalent B3- atoms. There are a spread of Ho–B bond distances ranging from 2.69–2.88 Å. Ni+1.50+ is bonded in a 4-coordinate geometry to four equivalent B3- atoms. There are a spread of Ni–B bond distances ranging from 2.02–2.07 Å. B3- is bonded in a 8-coordinate geometry to three equivalent Ho3+, four equivalent Ni+1.50+, and one B3- atom. The B–B bond length is 1.74 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(CuO2)2 by Materials Project

Ho(CuO2)2 crystallizes in the tetragonal I4_1/a space group. The structure is three-dimensional. Ho3+ is bonded in a 8-coordinate geometry to eight equivalent O2- atoms. There are four shorter (2.37 Å) and four longer (2.38 Å) Ho–O bond lengths. Cu+2.50+ is bonded in a square co-planar geometry to four equivalent O2- atoms. There is two shorter (1.90 Å) and two longer (1.92 Å) Cu–O bond length. O2- is bonded to two equivalent Ho3+ and two equivalent Cu+2.50+ atoms to form a mixture of distorted corner and edge-sharing OHo2Cu2 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(SiAu)2 by Materials Project

Ho(AuSi)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ho3+ is bonded to eight equivalent Si4- atoms to form HoSi8 hexagonal bipyramids that share corners with sixteen equivalent AuSi4 tetrahedra, edges with four equivalent HoSi8 hexagonal bipyramids, edges with eight equivalent AuSi4 tetrahedra, and faces with four equivalent HoSi8 hexagonal bipyramids. All Ho–Si bond lengths are 3.22 Å. Au+2.50+ is bonded to four equivalent Si4- atoms to form AuSi4 tetrahedra that share corners with eight equivalent HoSi8 hexagonal bipyramids, corners with four equivalent AuSi4 tetrahedra, edges with four equivalent HoSi8 hexagonal bipyramids, and edges with four equivalent AuSi4 tetrahedra. All Au–Si bond lengths are 2.56 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Ho3+, four equivalent Au+2.50+, and one Si4- atom. The Si–Si bond length is 2.29 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Aldehyde cool-flame chemistry explains a missing source of organic acids

Combustion emission is a significant source of organic acids, impacting atmospheric chemistry and climate. Their formation mechanisms, however, remain poorly understood, leading to underestimation in kinetic models. We investigate the cool-flame oxidation of key combustion intermediates—C 1 –C 4 aldehydes and benzaldehyde. Using in-situ synchrotron vacuum ultraviolet photoionization mass spectrometry, we observe the direct conversion of aldehydes to organic acids, a process enhanced by HO 2 radicals. Quantum chemistry calculations reveal that the reaction of RC(O)O 2 with HO 2 on the singlet potential energy surface contributes to organic acids. Incorporating this pathway into a kinetic model significantly improves organic acid prediction. Despite the high-temperature nature of engine combustion, significant spatial and temporal inhomogeneities (e.g., near-wall regions and crevice volumes) lead to localized cool-flame conditions, facilitating organic acid formation and emission. Elucidating the acid formation under cool-flame conditions provides a critical mechanism for accurately modelling anthropogenic organic acid emissions and developing mitigation strategies.

SVUV-PIMS↗
NASA NTRS1997

Kinetics Studies of the HO (sub 2) + CIO Reaction

The HO (sub 2) + CIO reaction is the key rate-limiting step in the chlorine-catalyzed destruction of ozone in the lower and middle stratosphere. Product channels leading to HOC1 and HC1 are both exothermic and a small HC1 channel will significantly alter the partitioning of inorganic chlorine in the lower stratosphere.

Kinetics ozone inorganic chlorine temperature↗
DOE OSTI2021

Assessment of sulfur trioxide formation due to enhanced interaction of nitrogen oxides and sulfur oxides in pressurized oxy-combustion

Pressurized oxy-combustion is emerging to be one of the best technologies for significantly decreasing the energy penalty for CO 2 capture in coal-fired power plants. However, the higher pressure boosts the formation of acid gases, including SO 3 and NO 2 , which could increase the risk of corrosion. The synergistic promotion of SO 3 and NO 2 formation in pressurized oxy-combustion is kinetically evaluated under representative conditions (1 ~ 30 atm, 600 ~ 1200 °C, NO/SO 2 = 0.1 ~ 5). We begin with a comprehensive mechanism (72 species and 428 reactions), covering nitrogen and sulfur chemistry, relying on GRI-Mech 3.0. This analysis shows that the interaction of SO X and NO X enhances the conversion rates of SO 2 → SO 3 , and this effect is more apparent at elevated pressures and lower temperatures. Mechanism analyses indicate that at elevated pressures, the formation pathways of SO 3 through HOSO 2 + O 2 = SO 3 + HO 2 , and NO 2 through HO 2 + NO = NO 2 + OH, are promoted due to the strong interaction between SO X and NO X . The intermediate between these two reactions is SO 2 + OH + M = HOSO 2 + M, resulting in a strong cycle, that can be expressed by the global reaction NO + SO 2 + O 2 = NO 2 + SO 3 . Finally, a nine-step reduced chemistry is developed and validated to accurately predict the formation of SO 3 in the post-flame region at elevated pressures.

42 ENGINEERING↗