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Results for “formic acid”

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.

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At least 271 records · Page 15
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Optimization and active stabilization of a far-infrared laser for NSTX-U high poloidal wavenumber scattering diagnostics

The far-infrared (FIR) laser output beam power and profile are important parameters in the laser-aided diagnostics, directly influencing the spatial resolution and signal-to-noise ratio of measurements. Here, this work focuses on developing a systematic control method to enhance FIR laser beam quality through optimized mirror alignment and real-time feedback-based precision cavity length tuning. A 150 W CO 2 laser, aligned with the waveguide axis using a HeNe reference laser, serves as the pump source. The sensitivity of FIR beam intensity to pump gas pressure and thermal expansion is investigated, revealing that even a 1 µm cavity expansion can significantly degrade output power stability to about two-thirds of its original value. To address this, a feedback control module has been designed and implemented for active cavity length adjustment, stabilizing the output power at ∼30 mW. In addition, maintaining a high formic acid gas pressure ($>$190 mTorr) within the cavity ensures reliable operation. The optimized FIR laser will be deployed on the National Spherical Torus eXperiment-U high poloidal wavenumber scattering system for studying electron-scale turbulence in tokamak plasmas.

Xu, Xinhang [Univ. of California, Davis, CA (Unite↗
DOE OSTI2020

A requirement for an active proton delivery network supports a compound I-mediated C–C bond cleavage in CYP51 catalysis

CYP51 enzymes (sterol 14α-demethylases) are cytochromes P450 that catalyze multistep reactions. The CYP51 reaction occurs in all biological kingdoms and is essential in sterol biosynthesis. It removes the 14α-methyl group from cyclized sterol precursors by first forming an alcohol, then an aldehyde, and finally eliminating formic acid with the introduction of a Δ14–15 double bond in the sterol core. The first two steps are typical hydroxylations, mediated by an electrophilic compound I mechanism. The third step, C–C bond cleavage, has been proposed to involve either compound I (i.e. FeO 3+ ) or, alternatively, a proton transfer-independent nucleophilic ferric peroxo anion (compound 0, i.e. Fe 3+ O 2 – ). In this work, using comparative crystallographic and biochemical analyses of WT human CYP51 (CYP51A1) and its D231A/H314A mutant, whose proton delivery network is destroyed (as evidenced in a 1.98-Å X-ray structure in complex with lanosterol), we demonstrate that deformylation of the 14α-carboxaldehyde intermediate requires an active proton relay network to drive the catalysis. These results indicate a unified, compound I-based mechanism for all three steps of the CYP51 reaction, as previously established for CYP11A1 and CYP19A1. We anticipate that our approach can be applied to mechanistic studies of other P450s that catalyze multistep reactions, such as C–C bond cleavage.

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

Catalytic reduction of carbon dioxide to methanol over defect-laden hexagonal boron nitride: insights into reaction mechanisms

Abstract We present a density functional theory-based mechanistic understanding of CO 2 hydrogenation to value-added products on a nitrogen-vacancy (V N ) defect in hexagonal boron nitride ( dh -BN). Activation occurs through back-donation to the π * orbitals of CO 2 from the frontier orbitals (defect state) of the h- BN sheet that are localized near a nitrogen-vacancy. Subsequent hydrogenation to methanol (CH 3 OH) and formic acid (HCOOH) proceed through vacancy-facilitated co-adsorption of hydrogen and CO 2 . More importantly, our reaction pathway analyses complimented by microkinetic modeling indicate that dh -BN is potentially a low-temperature, selective catalyst for CO 2 reduction to methanol. Our findings are in agreement with experiments conducted in a mechanical reactor that show high selectivity towards methanol formation for CO 2 hydrogenation on defect induced h- BN.

Jiang, Tao (ORCID:0000000304197288)↗
DOE OSTI2021

A highly efficient atomically thin curved PdIr bimetallene electrocatalyst

Abstract The multi-metallene with an ultrahigh surface area has great potential in precise tuning of surface heterogeneous d-electronic correlation by surface strain effect for the distinctive surface electronic structure, which is a brand new class of promising 2D electrocatalyst for sustainable energy device application. However, achieving such an atomically thin multi-metallene still presents a great challenge. Herein, we present a new synthetic method for an atomic-level palladium-iridium (PdIr) bimetallene with an average thickness of only ∼1.0 nm for achieving superior catalysis in the hydrogen evolution reaction (HER) and the formic acid oxidation reaction (FAOR). The curved PdIr bimetallene presents a top-ranked high electrochemical active area of 127.5 ± 10.8 m2 gPd+Ir−1 in the reported noble alloy materials, and exhibits a very low overpotential, ultrahigh activity and improved stability for HER and FAOR. DFT calculation reveals that the PdIr bimetallene herein has a unique lattice tangential strain, which can induce surface distortion while concurrently creating a variety of concave-convex featured micro-active regions formed by variously coordinated Pd sites agglomeration. Such a strong strain effect correlates the abnormal on-site active 4d10-t2g-orbital Coulomb correlation potential and directly elevates orbital-electronegativity exposure within these active regions, resulting in a preeminent barrier-free energetic path for significant enhancement of FAOR and HER catalytic performance.

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

Evolutionary and functional relationships between plant and microbial C 1 metabolism in terrestrial ecosystems

One-carbon (C 1 ) metabolism, centered on the universal methyl donor S-adenosyl methionine (SAM), plays critical roles in biosynthesis, redox regulation, and stress responses across plants and microbes. A recently proposed photosynthetic C 1 pathway links SAM methyl groups directly to RuBisCO-mediated CO 2 assimilation and integrates with nitrogen and sulfur metabolism. Light-dependent SAM synthesis may regulate the methylation of biopolymers and specialized metabolites and help mitigate photorespiratory stress under elevated temperature and drought. Phylogenetic analysis of two core enzymes suggests evolutionary continuity from methylotrophic microbes to land plants, supporting microbial origins via endosymbiotic gene transfer. Beyond intracellular roles, C 1 metabolism drives biosphere–atmosphere exchange via gases such as methane, methanol, formic acid, and formaldehyde, and numerous specialized volatiles synthesized through SAM methylation. S-methylmethionine, a mobile C 1 metabolite, may mediate phloem transport of reduced sulfur, nitrogen, and methyl groups, linking above- and belowground C 1 cycling in plants. Advances in real-time gas sensing now allow the high-frequency quantification of C 1 fluxes from leaves, stems, and soils, highlighting C 1 metabolism as a critical and underrecognized component of terrestrial carbon and nutrient cycling. Given its microbial ancestry and the production of diverse volatile biosignatures, C 1 metabolism may also offer unique insights into life's origins and biosignature detection on exoplanets.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Materials Data on H22RhC3(N3O4)2 by Materials Project

RhN6H18(CO2)3(H2O)2 crystallizes in the orthorhombic Pnnm space group. The structure is zero-dimensional and consists of twelve formic acid molecules, eight water molecules, and four RhN6H18 clusters. In each RhN6H18 cluster, Rh4+ is bonded in an octahedral geometry to six N3- atoms. There are two shorter (2.10 Å) and four longer (2.11 Å) Rh–N bond lengths. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a trigonal non-coplanar geometry to one Rh4+ and three H1+ atoms. There is two shorter (1.03 Å) and one longer (1.04 Å) N–H bond length. In the second N3- site, N3- is bonded in a trigonal non-coplanar geometry to one Rh4+ and three H1+ atoms. All N–H bond lengths are 1.03 Å. There are five inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H9C3N3O2 by Materials Project

C2N3H8CHO2 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of four formic acid molecules and four methylguanidinium molecules.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H11C4NO10 by Materials Project

NH4(CH3O3)2HC2O4 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two ammonium molecules, four formic acid water molecules, and two HC2O4 clusters. In each HC2O4 cluster, there are two inequivalent C3+ sites. In the first C3+ site, C3+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.26 Å) and one longer (1.27 Å) C–O bond length. In the second C3+ site, C3+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.24 Å) and one longer (1.30 Å) C–O bond length. H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.11 Å) and one longer (1.35 Å) H–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one C3+ and one H1+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C3+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one C3+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one C3+ and one H1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CuH2(CO2)2 by Materials Project

Cu(HCOO)2 crystallizes in the orthorhombic Pbca space group. The structure is one-dimensional and consists of eight formic acid molecules and four CuCHO2 ribbons oriented in the (0, 1, 0) direction. In each CuCHO2 ribbon, Cu2+ is bonded in a distorted bent 150 degrees geometry to two O2- atoms. There is one shorter (1.87 Å) and one longer (1.90 Å) Cu–O bond length. C2+ is bonded in a trigonal planar geometry to one H1+ and two O2- atoms. The C–H bond length is 1.10 Å. There is one shorter (1.25 Å) and one longer (1.28 Å) C–O bond length. H1+ is bonded in a single-bond geometry to one C2+ atom. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to one Cu2+ and one C2+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Cu2+ and one C2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H10C2N2O5 by Materials Project

(NH4)2(CO2)2H2O crystallizes in the orthorhombic P2_12_12 space group. The structure is zero-dimensional and consists of four ammonium molecules, four formic acid molecules, and two water molecules.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H22IrC3(N3O4)2 by Materials Project

IrN6H18(CO2)3(H2O)2 crystallizes in the orthorhombic Pnnm space group. The structure is zero-dimensional and consists of four azane;iridium molecules, twelve formic acid molecules, and eight water molecules.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SbH3C2(O2F3)2 by Materials Project

CHO2CSbH2(OF3)2 crystallizes in the monoclinic Cc space group. The structure is zero-dimensional and consists of four formic acid molecules and four CSbH2(OF3)2 clusters. In each CSbH2(OF3)2 cluster, C4+ is bonded in a bent 120 degrees geometry to two O2- atoms. Both C–O bond lengths are 1.28 Å. Sb3+ is bonded in an octahedral geometry to six F1- atoms. There are a spread of Sb–F bond distances ranging from 1.90–1.95 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to one O2- and one F1- atom. The H–O bond length is 1.02 Å. The H–F bond length is 1.59 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one C4+ and one H1+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one C4+ and one H1+ atom. There are six inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one Sb3+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one Sb3+ atom. In the third F1- site, F1- is bonded in a distorted single-bond geometry to one Sb3+ atom. In the fourth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Sb3+ and one H1+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one Sb3+ atom. In the sixth F1- site, F1- is bonded in a single-bond geometry to one Sb3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on UH16C4(NO3)4 by Materials Project

UO2(NH4)3(CO2)4NH2OH2O crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of twelve ammonium molecules; sixteen formic acid molecules; four hydroxylamine molecules; four pitchblend, uranium(iv) oxide, uranium(iv) dioxide, uranium dioxide molecules; and four water molecules.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CoH22C3(N3O4)2 by Materials Project

Co(NH3)6(CO2)3(H2O)2 crystallizes in the orthorhombic Pnnm space group. The structure is zero-dimensional and consists of four azane;cobalt molecules, twelve formic acid molecules, and eight water molecules.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H6C6NO by Materials Project

C6H4NHOH crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one formic acid molecule, one trimethylamine molecule, and one C8NH5 cluster. In the C8NH5 cluster, there are eight inequivalent C+0.17- sites. In the first C+0.17- site, C+0.17- is bonded in a trigonal planar geometry to three C+0.17- atoms. There is two shorter (1.42 Å) and one longer (1.44 Å) C–C bond length. In the second C+0.17- site, C+0.17- is bonded in a distorted trigonal planar geometry to two C+0.17- and one H1+ atom. The C–C bond length is 1.38 Å. The C–H bond length is 1.09 Å. In the third C+0.17- site, C+0.17- is bonded in a distorted single-bond geometry to one C+0.17- and one H1+ atom. The C–H bond length is 1.09 Å. In the fourth C+0.17- site, C+0.17- is bonded in a distorted single-bond geometry to one C+0.17- and one H1+ atom. The C–C bond length is 1.38 Å. The C–H bond length is 1.09 Å. In the fifth C+0.17- site, C+0.17- is bonded in a distorted trigonal planar geometry to two C+0.17- and one H1+ atom. The C–H bond length is 1.09 Å. In the sixth C+0.17- site, C+0.17- is bonded in a distorted trigonal planar geometry to two C+0.17- and one H1+ atom. The C–C bond length is 1.38 Å. The C–H bond length is 1.09 Å. In the seventh C+0.17- site, C+0.17- is bonded in a bent 120 degrees geometry to two C+0.17- atoms. The C–C bond length is 1.43 Å. In the eighth C+0.17- site, C+0.17- is bonded in a linear geometry to one C+0.17- and one N3- atom. The C–N bond length is 1.17 Å. N3- is bonded in a single-bond geometry to one C+0.17- atom. There are five inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one C+0.17- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one C+0.17- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one C+0.17- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one C+0.17- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one C+0.17- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZnC4(N2O)4 by Materials Project

Zn(CN4)2(CO2)2 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional and consists of eight formic acid molecules and one Zn(CN4)2 framework. In the Zn(CN4)2 framework, Zn2+ is bonded in a tetrahedral geometry to four equivalent N+1.25- atoms. All Zn–N bond lengths are 2.03 Å. C4+ is bonded in a water-like geometry to two equivalent N+1.25- atoms. Both C–N bond lengths are 1.34 Å. There are two inequivalent N+1.25- sites. In the first N+1.25- site, N+1.25- is bonded in a 3-coordinate geometry to one Zn2+, one C4+, and one N+1.25- atom. The N–N bond length is 1.36 Å. In the second N+1.25- site, N+1.25- is bonded in a distorted water-like geometry to two N+1.25- atoms. The N–N bond length is 1.30 Å.

36 MATERIALS SCIENCE↗