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At least 631 records · Page 35
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on TmSnIr by Materials Project

TmIrSn crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Tm is bonded in a 11-coordinate geometry to five Ir and six equivalent Sn atoms. There are four shorter (2.99 Å) and one longer (3.03 Å) Tm–Ir bond lengths. There are two shorter (3.16 Å) and four longer (3.28 Å) Tm–Sn bond lengths. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 9-coordinate geometry to three equivalent Tm and six equivalent Sn atoms. All Ir–Sn bond lengths are 2.76 Å. In the second Ir site, Ir is bonded in a 9-coordinate geometry to six equivalent Tm and three equivalent Sn atoms. All Ir–Sn bond lengths are 2.81 Å. Sn is bonded in a 10-coordinate geometry to six equivalent Tm and four Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NdSi2Ir3 by Materials Project

NdIr3Si2 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Nd is bonded in a 12-coordinate geometry to two equivalent Nd, twelve Ir, and six equivalent Si atoms. Both Nd–Nd bond lengths are 3.65 Å. There are a spread of Nd–Ir bond distances ranging from 3.18–3.55 Å. There are a spread of Nd–Si bond distances ranging from 3.18–3.37 Å. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 12-coordinate geometry to four equivalent Nd and four equivalent Si atoms. All Ir–Si bond lengths are 2.48 Å. In the second Ir site, Ir is bonded in a 4-coordinate geometry to four equivalent Nd and four equivalent Si atoms. There are two shorter (2.44 Å) and two longer (2.46 Å) Ir–Si bond lengths. Si is bonded in a 10-coordinate geometry to three equivalent Nd and six Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on B5Ir3W2 by Materials Project

W2Ir3B5 crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. W2+ is bonded in a 7-coordinate geometry to six B3- atoms. There are a spread of W–B bond distances ranging from 2.22–2.31 Å. There are two inequivalent Ir+3.67+ sites. In the first Ir+3.67+ site, Ir+3.67+ is bonded in an L-shaped geometry to two equivalent B3- atoms. Both Ir–B bond lengths are 2.18 Å. In the second Ir+3.67+ site, Ir+3.67+ is bonded in a 4-coordinate geometry to four B3- atoms. There are one shorter (2.20 Å) and three longer (2.21 Å) Ir–B bond lengths. There are three inequivalent B3- sites. In the first B3- site, B3- is bonded in a 7-coordinate geometry to three equivalent W2+, one Ir+3.67+, and three equivalent B3- atoms. There is two shorter (1.77 Å) and one longer (1.89 Å) B–B bond length. In the second B3- site, B3- is bonded in a 7-coordinate geometry to three equivalent W2+, one Ir+3.67+, and three equivalent B3- atoms. In the third B3- site, B3- is bonded in a 6-coordinate geometry to six Ir+3.67+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Reversible CO 2 Hydrogenation, Neutron Crystallography, and Hydride Reactivity of a Triiridium Heptahydride Complex

Abstract The authors report the structure, reactivity, and catalytic utility of a triiridium complex, [Ir 3 H 6 ( μ 3 ‐H)(PN) 3 ] 2+ ( 2‐H , PN = (2‐pyridyl)CH 2 PBu t 2 ). Despite its unusual stability to unsaturated organics, electrophiles, and even CF 3 SO 3 D, they find that complex 2‐H catalyzes hydrogenation of CO 2 to formate (TON Ir = 9600) and reverse formic acid dehydrogenation (TON Ir = 54 400). The hydrogenation operates via a reactive intermediate [Ir 3 H 4 ( μ ‐H) 4 (PN) 3 ] + ( 5 ). Neutron crystallography and DFT‐supported neutron vibrational spectroscopy of 2‐H reveal Ir─H bond lengths and elucidate the vibration modes within the Ir 3 H 7 core. Stoichiometric oxidation of 2‐H produces four classes of iridium complexes of varied nuclearity and hydride structure: tetra‐ and pentanuclear clusters [Ir 3 H 6 ( μ 3 ‐AuPPh 3 )(PN) 3 ] 2+ ( 2‐Au ) and [Ag{Ir 2 H 4 ( μ ‐OAc)(PN) 2 } 2 ] 3+ ( 6 ) are generated using AuPPh 3 + and AgOAc, respectively. Further oxidation to class [Ir 2 H 3 ( μ ‐X) 2 (PN) 2 ] + is possible with AgOAc, Hg(OAc) 2 , or I 2 . Finally, a TEMPO/HCl system completely oxidizes the hydrides and gives [Ir 2 Cl 4 ( μ ‐Cl) 2 (PN) 2 ] ( 11 ).

Cherepakhin, Valeriy [Loker Hydrocarbon Research I↗
DOE OSTI2025

Reversible CO 2 Hydrogenation, Neutron Crystallography, and Hydride Reactivity of a Triiridium Heptahydride Complex

Here, the authors report the structure, reactivity, and catalytic utility of a triiridium complex, [Ir 3 H 6 (μ 3 -H)(PN) 3 ] 2+ (2-H, PN = (2-pyridyl)CH 2 PBu t 2 ). Despite its unusual stability to unsaturated organics, electrophiles, and even CF 3 SO 3 D, they find that complex 2-H catalyzes hydrogenation of CO 2 to formate (TON Ir = 9600) and reverse formic acid dehydrogenation (TON Ir = 54 400). The hydrogenation operates via a reactive intermediate [Ir 3 H 4 (μ-H) 4 (PN) 3 ] + (5). Neutron crystallography and DFT-supported neutron vibrational spectroscopy of 2-H reveal Ir─H bond lengths and elucidate the vibration modes within the Ir 3 H 7 core. Stoichiometric oxidation of 2-H produces four classes of iridium complexes of varied nuclearity and hydride structure: tetra- and pentanuclear clusters [Ir 3 H 6 (μ 3 -AuPPh 3 )(PN) 3 ] 2+ (2-Au) and [Ag{Ir 2 H 4 (μ-OAc)(PN) 2 } 2 ] 3+ (6) are generated using AuPPh 3 + and AgOAc, respectively. Further oxidation to class [Ir 2 H 3 (μ-X) 2 (PN) 2 ] + is possible with AgOAc, Hg(OAc) 2 , or I 2 . Finally, a TEMPO/HCl system completely oxidizes the hydrides and gives [Ir 2 Cl 4 (μ-Cl) 2 (PN) 2 ] (11).

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Iridium-cobalt oxide synthesized via surfactant-assisted Adams fusion for efficient oxygen evolution in acidic and alkaline media

A series of iridium-cobalt (Ir-Co) oxide catalysts were synthesized using a modified surfactant-assisted Adams fusion method and evaluated for the oxygen evolution reaction (OER) in both acidic and alkaline media. The effect of varying the Ir/Co ratio was systematically studied and compared with commercial Ir black and pure IrO 2 samples. The actual elemental ratios were quantified using X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), and inductively coupled plasma-mass spectrometry (ICP-MS). Among the synthesized samples, the Ir 6 Co 4 catalyst exhibited the best performance in acidic media, achieving an iR-corrected overpotential of 292 mV. In alkaline conditions, it demonstrated comparable activity to Ir black, with an iR-corrected overpotential of 263 mV. XPS and electron energy loss spectroscopy analyses revealed that increasing Co content led to a higher fraction of metallic Ir (Ir 0 ) in the catalyst. In addition, the role of Ir 3+ in enhancing OER activity was explored. A strong correlation was observed between higher Ir 3+ content and improved OER performance in acidic conditions.

Adams fusion↗
DOE OSTI2021

Ubiquitin-specific protease 14 promotes radio-resistance and suppresses autophagy in oral squamous cell carcinoma

Highlights: • USP14 promotes radioresistance of OSCC cells. • USP14 elevates radioresistance of OSCC cells by suppressing apoptosis. • USP14 modulates radioresistance in OSCC by regulating autophagy. Oral squamous cell carcinoma (OSCC) is a common malignant tumor in the world. Radiotherapy is one of the standard therapies for patients with OSCC, but its clinical efficiency is limited due to radioresistance. In this study, we identified a mechanism of such resistance regulated by Ubiquitin-specific protease 14 (USP14). USP14 expression was significantly increased in clinical OSCC tissue samples and cell lines, and OSCC patients with high USP14 expression predicted poor overall survival rate. Additionally, a negative correlation between USP14 and LC3B was observed in patients with OSCC. We then found that irradiation (IR)-reduced cell survival of OSCC cells lines was further decreased when USP14 was knocked down. However, USP14 over-expression significantly promoted the cell viability of OSCC cells after IR treatment. Colony formation analysis confirmed thatafter IR treatment,USP14 knockdown markedly decreased the proliferation of OSCC cells, but over-expressing USP14 significantly up-regulated the proliferative activity of OSCC cells. Furthermore, DNA damage caused by IR was enhanced by USP14 knockdown, while been suppressed in OSCC cells with USP14 over-expression. Additionally, IR-inducedapoptosis was further promoted by USP14 knockdown in OSCC cells, which was, however, significantly abolished by USP14 over-expression.Moreover, our in vivo studies showed that IR-reduced tumor growth and tumor weight were further enhanced by USP14 knockdown in OSCC tumor-bearing nude mice. Finally, we found that USP14 knockdown could promote IR-induced autophagy by increasing LC3BII and γH2AX expression levels in IR-treated OSCC cells. However, this event was markedly abolished by ATG5 knockdown, subsequently restoring the cell proliferation in IR-incubated OSCC cells.Finally, we found that USP14-mediated apoptosis was autophagy-dependent in IR-treated OSCC cells. Taken together, these findings suggested that suppressing USP14 could alleviateradioresistancein OSCC both in vitro and in vivo by inducing apoptosis and autophagy, and thus could be served as a promising therapeutic strategy for OSCC treatment.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2025

Strong Coupling of Iridium and Boron–Carbon-Nitride Support for Enhanced Acidic Water Oxidation

Supporting iridium (Ir)-based materials on stable and suitable substrates is an efficient strategy to improve their catalytic performance for the oxygen evolution reaction (OER) in harsh acidic environments. Herein, we report a series of Ir catalysts supported on boron–carbon-nitride (BCN), denoted as Ir/BCN. Detailed experiments combined with density functional theory calculations demonstrate strong interactions between Ir nanoparticles (NPs) and the BCN support, significantly contributing to the improved OER performance. Among the synthesized catalysts, the Ir/BCN-75 catalyst outperforms commercial Ir black and IrO 2 in both half-cell and proton exchange membrane water electrolysis (PEMWE) tests. Specially, the Ir/BCN-75 catalyst achieves a high current density of 2.94 A cm –2 at 1.9 V with a low Ir loading of 0.26 mg cm –2 in PEMWE measurements, exceeding most Ir-based catalysts reported to date. The BCN support interacts strongly with Ir, wherein Ir–N bonding directs the Ir NP growth and enhances electrocatalytic activity, while Ir–B bonding contributes to the stability of the Ir/BCN catalyst.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Subaru/HSC deep optical imaging of infrared sources in the AKARI North Ecliptic Pole-Wide field

In this work, we present a five-broad-band (grizy) photometric catalogue of Subaru/Hyper Suprime-Cam (HSC) optical imaging observations at around the North Ecliptic Pole (NEP) where the AKARI infrared (IR) satellite conducted a large survey (NEP-Wide survey). The observations cover almost all the NEP-Wide survey field down to the depth of 28.1, 26.8, 26.3, 25.5, and 25.0 mag (5σ) at grizy, respectively. The five-band HSC catalogue contains about 2.6 million objects, and 70 959 AKARI NEP-Wide counterpart sources are identified in the catalogue. We added existing supplementary catalogues from the u band to the far-IR band, and estimated photo-z for the AKARI-HSC sources. We achieved σΔz/(1 + zs) = 0.06 and an outlier rate of 13.4 per cent at z = 0.2–1.5. Using the spectral energy distribution (SED) template fitting, we classified the AKARI-HSC galaxies into four categories, namely quiescent, star-forming, Type1 active galactic nucleus (AGN), and Type2 AGN, in each redshift bin. Then, at z > 1, the mean SED of star-forming galaxies in mid-IR (3–10 μm) range is significantly different from that of spiral galaxies in the nearby Universe, indicating that many of star-forming galaxies at z > 1 contain a heat source capable of heating dust to temperatures that radiate thermal emission in the mid-IR range. Furthermore, we estimated the number fraction of AGNs (fAGN) in each bin of redshift and IR luminosity (L IR ), and examined the dependence of redshift and L IR . In log(L IR /L ⊙ ) = 11.0–14.0, the fAGN shows a significant increase with increasing redshift, regardless of the LIR bins. In contrast, the fAGN shows a slight increase against L IR at z < 1 and no increase with increasing L IR at z > 1.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2020

Materials Data on Mg13Ir3 by Materials Project

Mg13Ir3 crystallizes in the trigonal R-3c space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a linear geometry to two equivalent Ir atoms. Both Mg–Ir bond lengths are 2.73 Å. In the second Mg site, Mg is bonded in a bent 150 degrees geometry to two equivalent Ir atoms. Both Mg–Ir bond lengths are 2.75 Å. In the third Mg site, Mg is bonded in a trigonal planar geometry to three equivalent Ir atoms. All Mg–Ir bond lengths are 2.77 Å. In the fourth Mg site, Mg is bonded in a 2-coordinate geometry to two equivalent Ir atoms. There are one shorter (2.71 Å) and one longer (2.83 Å) Mg–Ir bond lengths. Ir is bonded in a 9-coordinate geometry to nine Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaTm(Ge2Ir)2 by Materials Project

TmLa(IrGe2)2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Tm is bonded in a 8-coordinate geometry to six equivalent Ir and nine Ge atoms. There are two shorter (3.23 Å) and four longer (3.27 Å) Tm–Ir bond lengths. There are a spread of Tm–Ge bond distances ranging from 2.97–3.49 Å. La is bonded in a 8-coordinate geometry to four equivalent Ir and ten Ge atoms. All La–Ir bond lengths are 3.26 Å. There are a spread of La–Ge bond distances ranging from 3.32–3.44 Å. Ir is bonded in a 10-coordinate geometry to three equivalent Tm, two equivalent La, and five Ge atoms. There are a spread of Ir–Ge bond distances ranging from 2.49–2.60 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 8-coordinate geometry to three equivalent Tm, one La, three equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.70 Å. In the second Ge site, Ge is bonded in a 2-coordinate geometry to one Tm, four equivalent La, and two equivalent Ir atoms. In the third Ge site, Ge is bonded in a 9-coordinate geometry to two equivalent Tm, four equivalent La, two equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.60 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HoGe2Ir by Materials Project

HoIrGe2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Ho sites. In the first Ho site, Ho is bonded in a 8-coordinate geometry to six equivalent Ir and nine Ge atoms. There are four shorter (3.23 Å) and two longer (3.29 Å) Ho–Ir bond lengths. There are a spread of Ho–Ge bond distances ranging from 2.95–3.51 Å. In the second Ho site, Ho is bonded in a 8-coordinate geometry to four equivalent Ir and ten Ge atoms. All Ho–Ir bond lengths are 3.17 Å. There are a spread of Ho–Ge bond distances ranging from 3.25–3.41 Å. Ir is bonded in a 10-coordinate geometry to five Ho and five Ge atoms. There are a spread of Ir–Ge bond distances ranging from 2.47–2.63 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 8-coordinate geometry to four Ho, three equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.72 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to six Ho, two equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.48 Å. In the third Ge site, Ge is bonded in a 2-coordinate geometry to five Ho and two equivalent Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ErGe2Ir by Materials Project

ErIrGe2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Er sites. In the first Er site, Er is bonded in a 12-coordinate geometry to six equivalent Ir and nine Ge atoms. There are four shorter (3.23 Å) and two longer (3.29 Å) Er–Ir bond lengths. There are a spread of Er–Ge bond distances ranging from 2.94–3.51 Å. In the second Er site, Er is bonded in a 8-coordinate geometry to four equivalent Ir and ten Ge atoms. All Er–Ir bond lengths are 3.16 Å. There are a spread of Er–Ge bond distances ranging from 3.23–3.41 Å. Ir is bonded in a 10-coordinate geometry to five Er and five Ge atoms. There are a spread of Ir–Ge bond distances ranging from 2.47–2.62 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 8-coordinate geometry to four Er, three equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.71 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to six Er, two equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.48 Å. In the third Ge site, Ge is bonded in a 2-coordinate geometry to five Er and two equivalent Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TbGe2Ir by Materials Project

TbIrGe2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 8-coordinate geometry to six equivalent Ir and nine Ge atoms. There are four shorter (3.25 Å) and two longer (3.28 Å) Tb–Ir bond lengths. There are a spread of Tb–Ge bond distances ranging from 2.96–3.51 Å. In the second Tb site, Tb is bonded in a 8-coordinate geometry to four equivalent Ir and ten Ge atoms. All Tb–Ir bond lengths are 3.19 Å. There are a spread of Tb–Ge bond distances ranging from 3.27–3.42 Å. Ir is bonded in a 10-coordinate geometry to five Tb and five Ge atoms. There are a spread of Ir–Ge bond distances ranging from 2.48–2.64 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 8-coordinate geometry to four Tb, three equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.74 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to six Tb, two equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.49 Å. In the third Ge site, Ge is bonded in a 2-coordinate geometry to five Tb and two equivalent Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nd5Ir3 by Materials Project

Nd5Ir3 crystallizes in the tetragonal P4/ncc space group. The structure is three-dimensional. there are two inequivalent Nd sites. In the first Nd site, Nd is bonded to five Ir atoms to form distorted NdIr5 trigonal bipyramids that share corners with four equivalent NdIr4 tetrahedra, corners with eleven equivalent NdIr5 trigonal bipyramids, an edgeedge with one NdIr4 tetrahedra, edges with six equivalent NdIr5 trigonal bipyramids, and faces with two equivalent NdIr5 trigonal bipyramids. There are a spread of Nd–Ir bond distances ranging from 2.98–3.28 Å. In the second Nd site, Nd is bonded to four equivalent Ir atoms to form NdIr4 tetrahedra that share corners with sixteen equivalent NdIr5 trigonal bipyramids, edges with two equivalent NdIr4 tetrahedra, and edges with four equivalent NdIr5 trigonal bipyramids. All Nd–Ir bond lengths are 2.95 Å. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 8-coordinate geometry to eight Nd atoms. In the second Ir site, Ir is bonded in a 8-coordinate geometry to eight equivalent Nd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NdGe2Ir by Materials Project

NdIrGe2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Nd sites. In the first Nd site, Nd is bonded in a 8-coordinate geometry to six equivalent Ir and nine Ge atoms. There are two shorter (3.28 Å) and four longer (3.31 Å) Nd–Ir bond lengths. There are a spread of Nd–Ge bond distances ranging from 3.03–3.50 Å. In the second Nd site, Nd is bonded in a 8-coordinate geometry to four equivalent Ir and ten Ge atoms. All Nd–Ir bond lengths are 3.25 Å. There are a spread of Nd–Ge bond distances ranging from 3.33–3.46 Å. Ir is bonded in a 10-coordinate geometry to five Nd and five Ge atoms. There are a spread of Ir–Ge bond distances ranging from 2.49–2.68 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to six Nd, two equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.53 Å. In the second Ge site, Ge is bonded in a 2-coordinate geometry to five Nd and two equivalent Ir atoms. In the third Ge site, Ge is bonded in a 8-coordinate geometry to four Nd, three equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.78 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg3Ir by Materials Project

Mg3Ir crystallizes in the hexagonal P6_3cm space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 2-coordinate geometry to two equivalent Ir atoms. There are one shorter (2.74 Å) and one longer (2.77 Å) Mg–Ir bond lengths. In the second Mg site, Mg is bonded in a trigonal planar geometry to three equivalent Ir atoms. All Mg–Ir bond lengths are 2.69 Å. In the third Mg site, Mg is bonded in a distorted trigonal planar geometry to three equivalent Ir atoms. All Mg–Ir bond lengths are 2.66 Å. In the fourth Mg site, Mg is bonded in a distorted trigonal planar geometry to three equivalent Ir atoms. There are one shorter (2.74 Å) and two longer (2.83 Å) Mg–Ir bond lengths. Ir is bonded in a 8-coordinate geometry to eight Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZrIr by Materials Project

ZrIr crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Zr sites. In the first Zr site, Zr is bonded in a 5-coordinate geometry to seven Ir atoms. There are a spread of Zr–Ir bond distances ranging from 2.71–3.24 Å. In the second Zr site, Zr is bonded in a body-centered cubic geometry to eight Ir atoms. There are a spread of Zr–Ir bond distances ranging from 2.73–2.90 Å. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 8-coordinate geometry to eight Zr atoms. In the second Ir site, Ir is bonded in a 7-coordinate geometry to seven Zr atoms.

36 MATERIALS SCIENCE↗