SEARCH · Engineering Papers
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.
VMn is Tetraauricupride structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. V is bonded in a body-centered cubic geometry to eight equivalent Mn atoms. All V–Mn bond lengths are 2.49 Å. Mn is bonded in a body-centered cubic geometry to eight equivalent V atoms.
VMn(P2O7)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. V5+ is bonded to six O2- atoms to form VO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of V–O bond distances ranging from 1.86–1.92 Å. Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Mn–O bond distances ranging from 1.96–2.18 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one VO6 octahedra, corners with two equivalent MnO6 octahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 40–48°. There are a spread of P–O bond distances ranging from 1.51–1.61 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one VO6 octahedra, corners with two equivalent MnO6 octahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 24–49°. There are a spread of P–O bond distances ranging from 1.52–1.62 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one MnO6 octahedra, corners with two equivalent VO6 octahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 31–44°. There are a spread of P–O bond distances ranging from 1.48–1.61 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one MnO6 octahedra, corners with two equivalent VO6 octahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–52°. There are a spread of P–O bond distances ranging from 1.49–1.62 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one V5+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one V5+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mn3+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one V5+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one V5+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V5+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the eighth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Mn3+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Mn3+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Mn3+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V5+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mn3+ and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mn3+ and one P5+ atom.
VMn(Co2Si)2 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. V2+ is bonded in a 8-coordinate geometry to eight Co1+ and six equivalent Si4- atoms. There are two shorter (2.44 Å) and six longer (2.45 Å) V–Co bond lengths. All V–Si bond lengths are 2.83 Å. Mn2+ is bonded in a 8-coordinate geometry to eight Co1+ and six equivalent Si4- atoms. There are two shorter (2.44 Å) and six longer (2.45 Å) Mn–Co bond lengths. All Mn–Si bond lengths are 2.82 Å. There are three inequivalent Co1+ sites. In the first Co1+ site, Co1+ is bonded in a distorted body-centered cubic geometry to one V2+, three equivalent Mn2+, and four equivalent Si4- atoms. All Co–Si bond lengths are 2.45 Å. In the second Co1+ site, Co1+ is bonded in a distorted body-centered cubic geometry to three equivalent V2+, one Mn2+, and four equivalent Si4- atoms. All Co–Si bond lengths are 2.45 Å. In the third Co1+ site, Co1+ is bonded in a distorted body-centered cubic geometry to one V2+, three equivalent Mn2+, and four equivalent Si4- atoms. All Co–Mn bond lengths are 2.45 Å. All Co–Si bond lengths are 2.45 Å. Si4- is bonded in a 8-coordinate geometry to three equivalent V2+, three equivalent Mn2+, and eight Co1+ atoms.
VMn(PO4)2 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. V4+ is bonded to six O2- atoms to form VO6 pentagonal pyramids that share corners with four equivalent MnO6 octahedra, corners with four PO4 tetrahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 46–52°. There are a spread of V–O bond distances ranging from 1.95–2.07 Å. Mn2+ is bonded to six O2- atoms to form distorted MnO6 octahedra that share corners with four equivalent VO6 pentagonal pyramids, corners with four PO4 tetrahedra, and an edgeedge with one PO4 tetrahedra. There are a spread of Mn–O bond distances ranging from 2.05–2.38 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one MnO6 octahedra, corners with three equivalent VO6 pentagonal pyramids, and an edgeedge with one MnO6 octahedra. The corner-sharing octahedral tilt angles are 56°. There are a spread of P–O bond distances ranging from 1.51–1.60 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent MnO6 octahedra, a cornercorner with one VO6 pentagonal pyramid, and an edgeedge with one VO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 35–62°. There are a spread of P–O bond distances ranging from 1.50–1.58 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one V4+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Mn2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one V4+, one Mn2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one V4+, one Mn2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one V4+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to one Mn2+ and one P5+ atom.
VMn(Ni2Sn)2 is Tungsten-derived structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. V is bonded in a distorted body-centered cubic geometry to eight Ni and six equivalent Sn atoms. There are two shorter (2.62 Å) and six longer (2.63 Å) V–Ni bond lengths. All V–Sn bond lengths are 3.03 Å. Mn is bonded in a distorted body-centered cubic geometry to eight Ni and six equivalent Sn atoms. All Mn–Ni bond lengths are 2.63 Å. All Mn–Sn bond lengths are 3.04 Å. There are four inequivalent Ni sites. In the first Ni site, Ni is bonded in a distorted body-centered cubic geometry to one V, three equivalent Mn, and four equivalent Sn atoms. All Ni–Sn bond lengths are 2.63 Å. In the second Ni site, Ni is bonded in a distorted body-centered cubic geometry to three equivalent V, one Mn, and four equivalent Sn atoms. There are one shorter (2.62 Å) and three longer (2.63 Å) Ni–Sn bond lengths. In the third Ni site, Ni is bonded in a distorted body-centered cubic geometry to three equivalent V, one Mn, and four equivalent Sn atoms. All Ni–V bond lengths are 2.63 Å. The Ni–Mn bond length is 2.63 Å. There are one shorter (2.62 Å) and three longer (2.63 Å) Ni–Sn bond lengths. In the fourth Ni site, Ni is bonded in a distorted body-centered cubic geometry to three equivalent V, one Mn, and four equivalent Sn atoms. All Ni–V bond lengths are 2.63 Å. There are one shorter (2.62 Å) and three longer (2.63 Å) Ni–Sn bond lengths. Sn is bonded in a 8-coordinate geometry to three equivalent V, three equivalent Mn, and eight Ni atoms.
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
VMn is beta Np-derived structured and crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. V is bonded in a 8-coordinate geometry to four equivalent V and four equivalent Mn atoms. All V–V bond lengths are 2.53 Å. All V–Mn bond lengths are 2.45 Å. Mn is bonded in a 8-coordinate geometry to four equivalent V and four equivalent Mn atoms. All Mn–Mn bond lengths are 2.53 Å.
Geophysical research on historical nuclear tests is an important aspect of future monitoring capabilities in seismic research. This research is challenging due to the limited number of digital seismic recordings during the peak of nuclear testing (1945-1992). These limited records are unique and non-reproducible data with potential high research impact. Releasing available nuclear explosion seismic records to the explosion monitoring community is thus of high value and is the motivation for this dataset release. The target of this effort was on compilation and quality control of regional seismic records of nuclear explosions recorded on Lawrence Livermore National Laboratory stations ELK, KNB, LAC, and MNV, known collectively as the Livermore National Network (LNN) (Figure 1). LNN was established in the early 1960s for the primary purpose of monitoring underground nuclear testing at the former Nevada Test Site (NTS), now known as the Nevada Nuclear Security Site (NNSS) following the signing of the Limited Test Ban Treaty (LTBT). LNN consisted initially of short-period vertical component Benioff’s recorded on film located at Mina, NV (MNV) and Kanab, Utah (KNB). LNN added two additional stations at Landers, CA (LAC) and Elko, NV (ELK) in 1967 and upgraded equipment to broadband seismometers recorded on frequency modulation (FM) tapes from 1967-1979, followed by digital recordings after 1979 (Jarpe, 1989). The digital recordings were on a variety of now obsolete media, including 9-track, Exabyte, and DAT tapes. Jarpe (1989) describes the seismic station instrumentation details over the period of deployment. LNN recorded valuable non-repeatable unique data of several hundreds of nuclear explosions at NNSS, as well as earthquakes and chemical and mining explosions (Walter, 2020). The details of these nuclear tests are provided in the Department of Energy Report NV-209 Rev 16 (DOE, 2015).
A general polymer-assisted spinodal decomposition strategy is used to prepare hierarchically porous sodium super ionic conductor (NASICON)-structured polyanion-type materials (e.g., Na 3 V 2 (PO 4 ) 3 , Li 3 V 2 (PO 4 ) 3 , K 3 V 2 (PO 4 ) 3 , Na 4 MnV(PO 4 ) 3 , and Na 2 TiV(PO 4 ) 3 ) in a tetrahydrofuran/ethanol/H 2 O synthesis system. Depending on the boiling point of solvents, the selective evaporation of the solvents induces both macrophase separation via spinodal decomposition and mesophase separation via self-assembly of inorganic precursors and amphiphilic block copolymers, leading to the formation of hierarchically porous structures. We find that the resulting hierarchically porous Na 3 V 2 (PO 4 ) 3 possessing large specific surface area (≈77 m 2 g -1 ) and pore volume (≈0.272 cm 3 g -1 ) shows a high specific capacity of 117.6 mAh g -1 at 0.1 C achieving the theoretical value and a long cycling life with 77% capacity retention over 1000 cycles at 5 C. This method presented here can open a facile avenue to synthesize other hierarchically porous polyanion-type materials.
Abstract The manipulation of mesoscale domain wall phenomena has emerged as a powerful strategy for designing ferroelectric responses in functional devices, but its full potential is not yet realized in the field of magnetism. This work shows a direct connection between magnetic response functions in mechanically strained samples of Mn 3 O 4 and MnV 2 O 4 and stripe‐like patternings of the bulk magnetization which appear below known magnetostructural transitions. Building off previous magnetic force microscopy data, a small‐angle neutron scattering is used to show that these patterns represent distinctive magnetic phenomena which extend throughout the bulk of two separate materials, and further are controllable via applied magnetic field and mechanical stress. These results are unambiguously connected to the anomalously large magnetoelastic and magnetodielectric response functions reported for these materials, by performing susceptibility measurements on the same crystals and directly correlating local and macroscopic data.