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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 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1993

An intercomparison of aircraft instrumentation for tropospheric measurements of carbonyl sulfide, hydrogen sulfide, and carbon disulfide

This paper reports results of NASA's Chemical Instrumentation and Test Evaluation (CITE 3) during which airborne measurements for carbonyl sulfide (COS), hydrogen sulfide (H2S), and carbon disulfide (CS2) were intercompared. Instrumentation included a gas chromatograph using flame photometric detection (COS, H2S, and CS2), a gas chromatograph using mass spectrometric detection (COS) and CS2), a gas chromatograph using fluorination and subsequent SF6 detection via electron capture (COS and CS2), and the Natusch technique (H2S). The measurements were made over the Atlantic Ocean east of North and South America during flights from NASA's Wallops Flight Center, Virginia, and Natal, Brazil, in August/September 1989. Most of the intercomparisons for H2S and CS2 were at mixing ratios less than 25 pptv and less than 10 pptv, respectively, with a maximum mixing ratio of about 100 pptv and 50 pptv, respectively. Carbonyl sulfide intercomparisons were at mixing ratios between 400 and 600 pptv. Measurements were intercompared from data bases constructed from time periods of simultaneous or overlapping measurements. Agreement among the COS techniques averaged about 5%, and individual measurements were generally within 10%. For H2S and at mixing ratio greater than 25 pptv, the instruments agreed on average to about 15%. At mixing ratios less than 25 pptv the agreement was about 5 pptv. For CS2 (mixing ratios less than 50 pptv), two techniques agreed on average to about 4 pptv, and the third exhibited a bias (relative to the other two) that varied in the range of 3-7 pptv. CS2 mixing ratios over the ocean east of Natal as measured by the gas chromatograph-mass spectrometer technique were only a few pptv and were below the detection limits of the other two techniques. The CITE 3 data are used to estimate the current uncertainty associated with aircraft measurements of COS, H2S, and CS2 in the remote troposphere.

Gregory, Gerald L.↗
DOE OSTI2017

A nanoscale Zr-based fluorescent metal-organic framework for selective and sensitive detection of hydrogen sulfide

Hydrogen sulfide (H{sub 2}S) has been commonly viewed as a gas signaling molecule in various physiological and pathological processes. However, the highly efficient H{sub 2}S detection still remains challenging. Herein, we designed a new robust nano metal-organic framework (MOF) UiO-66-CH=CH{sub 2} as a fluorescent probe for rapid, sensitive and selective detection of biological H{sub 2}S. UiO-66-CH=CH{sub 2} was prepared by heating ZrCl{sub 4} and 2-vinylterephthalic acid via a simple method. UiO-66-CH=CH{sub 2} displayed fluorescence quenching to H{sub 2}S and kept excellent selectivity in the presence of biological relevant analytes especially the cysteine and glutathione. This MOF-based probe also exhibited fast response (10 s) and high sensitivity with a detection limit of 6.46 μM which was within the concentration range of biological H{sub 2}S in living system. Moreover, this constructed MOF featured water-stability, nanoscale (20–30 nm) and low toxicity, which made it a promising candidate for biological H{sub 2}S sensing. - Graphical abstract: A nanoscale Zr-based fluorescent metal-organic framework was synthesized for selective and sensitive biological detection of hydrogen sulfide. Display Omitted - Highlights: • We designed a new metal-organic framework UiO-66-CH=CH{sub 2} for biological H{sub 2}S sensing. • The responsive time was 10 s and the detection limit was 6.46 μM. • This probe has anti-interference especially from cysteine and glutathione. • This biological H{sub 2}S probe features low cytotoxicity, water-stability and nanoscale.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1972

Interstellar hydrogen sulfide.

Hydrogen sulfide has been detected in seven Galactic sources by observation of a single line corresponding to the rotational transition from the 1(sub 10) to the 1(sub 01) levels at 168.7 GHz. The observations show that hydrogen sulfide is only a moderately common interstellar molecule comparable in abundance to H2CO and CS, but somewhat less abundant than HCN and much less abundant than CO.

Thaddeus, P.↗
DOE OSTI2019

S -3-Carboxypropyl-l-cysteine specifically inhibits cystathionine γ-lyase–dependent hydrogen sulfide synthesis

Hydrogen sulfide (H 2 S) is a gaseous signaling molecule, which modulates a wide range of mammalian physiological processes. Cystathionine γ-lyase (CSE) catalyzes H 2 S synthesis and is a potential target for modulating H 2 S levels under pathophysiological conditions. CSE is inhibited by propargylglycine (PPG), a widely used mechanism-based inhibitor. In this study, we report that inhibition of H 2 S synthesis from cysteine, but not the canonical cystathionine cleavage reaction catalyzed by CSE in vitro, is sensitive to preincubation of the enzyme with PPG. In contrast, the efficacy of S-3-carboxpropyl-L-cysteine (CPC) a new inhibitor described herein, was not dependent on the order of substrate/inhibitor addition. We observed that CPC inhibited the γ-elimination reaction of cystathionine and H2S synthesis from cysteine by human CSE with Ki values of 50 ± 3 and 180 ± 15 μM, respectively. We noted that CPC spared the other enzymes involved either directly (cystathionine β-synthase and mercaptopyruvate sulfurtransferase) or indirectly (cysteine aminotransferase) in H2S biogenesis. CPC also targeted CSE in cultured cells, inhibiting transsulfuration flux by 80–90%, as monitored by the transfer of radiolabel from [35S]methionine to GSH. The 2.5 Å resolution crystal structure of human CSE in complex with the CPC-derived aminoacrylate intermediate provided a structural framework for the molecular basis of its inhibitory effect. In summary, our study reveals a previously unknown confounding effect of PPG, widely used to inhibit CSE-dependent H 2 S synthesis, and reports on an alternative inhibitor, CPC, which could be used as a scaffold to develop more potent H 2 S biogenesis inhibitors.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Hydrogen sulfide as a source of hydrogen production

Potentialities and perspectives of using the known processes of hydrogen sulfide decomposition (thermal, plasmochemical, electrochemical, and photochemical) to produce hydrogen are examined. The results of theoretical and experimental studies of hydrogen sulfide dissociation on the surface of single crystals are presented. The data on the low-temperature decomposition of H{sub 2}S on the sulfide and metal catalysts are discussed. The electronic structure of diatomic sulfur and thermodynamics of its formation in the processes of H{sub 2}S decomposition are considered. The decomposition of hydrogen sulfide on the heterogeneous catalysts placed under the solvent layer is shown to be promising. The mechanism of assimilation of hydrogen sulfide by colorless sulfur bacteria is proposed.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS2024

Exposure Limits for Hydrogen Sulfide in Spaceflight

Hydrogen sulfide (H 2 S) has not historically been detected in spacecraft, but the possible evolution of volatile components from polar ice on the lunar surface is a potential concern for NASA’s planned Artemis missions. Numerous case reports and occupational epidemiological studies document that exposure to H 2 S at high concentrations has effects on the respiratory system, potentially leading to unconsciousness followed by debilitating neurological effects. Studies in rodents demonstrate sensitivity of the respiratory system to lower concentrations of H 2 S. Adverse respiratory effects have also been indicated in workers chronically exposed to H 2 S. The objective of the present publication is to develop Spacecraft Maximum Allowable Concentrations (SMACs) for H 2 S for all current standard durations of exposure for spaceflight (1-hour, 24-hours, 7-days, 30-days, 180-days, and 1000-days). Summary sources and literature review were used to identify relevant studies to inform SMAC development. Space flight mission specific activities and most probable exposure scenarios were used to determine the relevant toxicity endpoints and supporting studies. SMACs were established for hydrogen sulfide of 5 ppm for 1-hour, 1.3 ppm for 24-hours, 1.3 ppm for 7-days, 1.3 ppm for 30-days, and 0.3 ppm for 180-days. Data are not sufficient currently to establish a 1000-day SMAC value. SMACs for H 2 S will support development of handling protocols and proper containment for lunar sample collection.

hydrogen sulfide↗
DOE OSTI2015

Atomic layer deposition of aluminum sulfide thin films using trimethylaluminum and hydrogen sulfide

Sequential exposures of trimethylaluminum and hydrogen sulfide are used to deposit aluminum sulfide thin films by atomic layer deposition (ALD) in the temperature ranging from 100 to 200 °C. Growth rate of 1.3 Å per ALD cycle is achieved by in-situ quartz crystal microbalance measurements. It is found that the growth rate per ALD cycle is highly dependent on the purging time between the two precursors. Increased purge time results in higher growth rate. Surface limited chemistry during each ALD half cycle is studied by in-situ Fourier transformed infrared vibration spectroscopy. Time of flight secondary ion-mass spectroscopy measurement is used to confirm elemental composition of the deposited films.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1994

Structure of 4-methylpyridinium Hydrogen Sulfide

4-Methylpyridinium hydrogen sulfide, (C6H7NH)HS, M(sub r) = 127.21, consists of C6H7NH(+) cations and HS(-) anions. Z = 2 for the crystal with monoclinic space group Cm (#8), dimensions of a = 8.679(2) A, b = 7.964(1) A, and c = 4.860(2) A, an angle beta of 101.10(2) degrees, and a volume of V = 329.6(3) A(exp 3). R = 0.039 and R(sub w) = 0.048 for 385 reflections with F(sub o)(exp 2) greater than 3 sigma(F(sub o)(exp 2)) and 59 variables. Both the C6H7NH(+) cation and the HS(-) anion lie on crystallographic mirror planes with the N,S, two carbon atoms, and two hydrogen atoms positioned in the planes. The hydrogen atom of the HS(-) anion was not located.

Andras, Maria T.↗
DOE OSTI2019

Synthesis of oleanolic acid/ursolic acid/glycyrrhetinic acid-hydrogen sulfide donor hybrids and their antitumor activity

A total of 25 targeted hydrogen sulfide donor–pentacyclic triterpene hybrids were designed, synthesized and evaluated on the basis of inspiring reports about hydrogen sulfide donor molecules and oleanolic acid derivatives on anti-tumor activity. The results revealed that only some hybrids (10a, 10b, 12a, 12b, 13a, and 15b) showed moderate anti-proliferation activity against K562 cell line. It indicated that oleanane-type, (R)-lipoic acid and TBZ groups were much more favorable to the anti-proliferation activity. Furthermore, C-3 OH was more beneficial than C-28/29 COOH in the oleanane-type to the antitumor activity of the batch of (R)-lipoic acid derivatives. And among them, only compound 13a exhibited moderate anti-proliferation activity against both K562 and K562/ADR cell lines, while it exhibited no anti-proliferation activity against BEL-7402 and L-O2 cell lines. Therefore, it suggested that it was not suitable for hybridization of hydrogen sulfide donors attached to oleanolic acid, ursolic acid and glycyrrhetinic acid in the field of anti-tumor.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Elastic properties of single crystal hydrogen sulfide: A Brillouin scattering study under high pressure-temperature

We have performed high pressure-temperature Brillouin scattering measurements on single crystal hydrogen sulfide using externally heated diamond anvil cell techniques. The pressure dependences of the acoustic velocities, isothermal elastic constants, and moduli of single crystal hydrogen sulfide have been determined along four isotherms. Both elastic constants and moduli increase monotonously with pressure along each isotherm, while they show a decreased tendency with temperature elevated under the same pressure points. The experimental equation of state of single crystal hydrogen sulfide is obtained by fitting with a third-order Birch-Murnaghan and Tait equation. It is proposed that the effect of hydrogen bonds contributes to the unique tendency of elastic anisotropy in single crystal hydrogen sulfide. Through our work, we have extended the melting curve and phase diagram of hydrogen sulfide up to 12 GPa and 580 K.

36 MATERIALS SCIENCE↗