Influence Of Hydrogen Sulfide Research Articles

Influence of hydrogen-sulfide on meiotic maturation and cumulus-expansion of porcine cumulus-oocyte complexes cultivated in vitro

Influence of hydrogen-sulfide on meiotic maturation and cumulus-expansion of porcine cumulus-oocyte complexes cultivated in vitro

Influence of Hydrogen Sulfide on the Corrosion-Mechanical Properties of Welded Joints of Pipe Steel

We determine the mechanical properties of the base metal and the metal of the heat-affected zone for welded joints of 17G1SU pipe steel in air and establish the influence of corrosion defects in these zones after preliminary holding in a NACE solution of hydrogen sulfide for 200 h. It is shown that the hydrogen-sulfide medium insignificantly changes the strength (σu, σ0.2) but noticeably affects the plasticity (ψ, δ) both of the base metal and of the weld metal. We also investigate their corrosion resistance, susceptibility to hydrogen-induced cracking, and the influence of preliminary hydrogen-sulfide corrosion on the corrosion-cracking resistance of welded joints.

INFLUENCE OF HYDROGEN SULFIDE ON THE PHOTOSYNTHETIC APPARATUS OF CHLOROBIUM LIMICOLA IMV K-8

Influence of hydrogen sulfide on Chlorobium limicola IМВ К-8 photosynthetic pigments composition and cells ultrastructure is studied. H2 S at concentrations 5–7 mM causes the decrease of pigments extracts optical density and absorption maximum at 421 nm transition to lower wavelength (406–408 nm). The results of pigments quantitative analysis after their separation by thin-layer chromatography have shown that at concentration 5 mM hydrogen sulfide causes 2.3 times decrease of bacteriochlorophylls content in bacterial cells, compared to control. The decrease of carotenoids content at this compound concentrations 5–6 mM is observed. At concentration 7 mM H2 S causes the disconnection of chlorosomes from cytoplasm membrane and the decrease of their quantity. Probably, chlorosomes degrade after the disconnection from membrane.

Вплив гідроген сульфіду на білковий склад клітинної стінки дріжджів Saccharomyces cerevisiae

Influence of hydrogen sulfide on the cell wall proteins composition of Saccharomyces cerevisiae yeasts is investigated. H 2 S considerably destroys the outer mannoprotein layer of the cell wall. The content of most of the covalently bound cell wall proteins, particularly, proteins with molecular weights 17, 24, 32, 37 and 53 kDa, is considerably decreased during yeasts’ cultivation with 10 mM of hydrogen sulfide for one day. The content of reducing sugars in the medium increased at the presence of hydrogen sulfide. At H 2 S concentration 20 and 30 mM none of the covalently bound cell wall proteins were observed. Among the non-covalently bound cell wall proteins of S. cerevisiae, the increase of proteins with molecular weights 110, 64, 51, 49, 26, 25, 23 and 16 kDa content and the decrease of proteins with molecular weights 42, 40, 29 and 27 kDa content is observed under the influence of 10 mM of hydrogen sulfide during one day. Under the short-term (1 hour) influence of H 2 S at different concentrations the increase of proteins with molecular weights 98, 94, 84, 78, 71, 68, 61, 42, 40 and 32 kDa content and the decrease of protein with molecular weight 49 kDa content was observed Keywords : Saccharomyces cerevisiae , hydrogen sulfide, cell wall.

Effect of contaminants on the thermodynamic properties of CO2 -rich fluids and ramifications in the design of surface and injection facilities for geologic CO2 sequestration

Abstract Geologic storage may involve injection of impure carbon dioxide (CO 2 ) streams in order to lower capture costs. The contaminants in the purified CO 2 stream depend on the type of power plant and the capture scheme. For on oxy-fuel based combustion cycle, we have previously evaluated the effect of presence of oxygen, nitrogen and argon on the CO 2 phase diagram and the critical properties of mixtures in these systems. For a 320 km pipeline, we established a base case for pure CO 2 , and evaluated the difference in compressor power requirements as each contaminant was added in fixed proportions. The key finding was that if the mixture encountered a two-phase region along the pipeline, the pressure drop becomes punitive. We proposed a minimal adjustment of operating conditions (or the temperature and pressure profile along the pipeline) to avoid the two-phase region and concomitant prohibitive pressure losses. In this paper, we consider the influence of hydrogen sulfide and water on the phase behavior of the CO 2 -rich captured stream. Specifically, we examine the phase equilibria and the PVT properties, and compare the GERG–2008 equation of state (EoS) computations with experimental data. In general, CO 2 -rich effluent mixtures from oxy-fuel plants may undergo phase separation at higher pressures than that for pure CO 2 for the temperature range likely to be encountered in surface and injection facilities designed for CO 2 sequestration. In addition, density, compressibility, and reactive properties of these mixtures may be significantly different from pure CO 2 . Consequently, operation of large geologic CO 2 storage sites must anticipate how these differences in the thermodynamic properties of the injected fluids may affect compressor power requirements, pipeline transport, well design, and wellbore and reservoir integrity.

Transformation of the mineral composition of ferromanganese crusts under the influence of hydrogen sulfide

Experiments devoted to interaction between the material of ferromanganese crusts (FMC) of Pacific seamounts and hydrogen sulfide at temperatures ranging from 100 to 600°C unraveled the formation of pyrite microcrystals at 100°C. Upon heating, the pyrite acquires more perfect crystalline form at 200°C and breaks down at 600°C. The formation and breakdown of magnetite take place according to the same similar scenario. At 200°C, one can see the formation of lumpy aggregates of the slightly crystallized alabandine transformed at 600°C into lamellar crystals, which accumulate the whole Mn and part of Fe hosted in rock. At maximal temperature, platinum and gold are crystallized selectively as lamellar particles and native sulfur is accumulated. The composition of these newly formed minerals is incomparable with the mineralogy of natural FMCs. This is inconsistent with the assumption about the possible influence of hypothetic hydrosulfuric emanations on the formation of minerals mentioned above. However, experimental results demonstrate an extremely high sorption capacity of FMCs relative to hydrogen sulfide, suggesting great prospects of the practical application of FMCs for the industrial and ecological purposes.

Influence of uniaxial tension on magnetic characteristics of the 12ΓБ pipe steel exposed to hydrogen sulfide

The results of measurements of the magnetic characteristics of specimens of the 12ΓБ pipe steel subjected to treatment with hydrogen sulfide for 96–384 h and also in the initial state, which were performed directly under the conditions of applied uniaxial tensile stresses to the point of specimen failure, are presented. The influence of hydrogen sulfide for 96 h has almost no effect on the mechanical and magnetic properties of the 12ΓБ steel, whereas a longer exposure leads to an appreciable decrease in the metal plasticity and an increase in its strength characteristics and the coercive force. The dependences of the magnetic characteristics on the degree of deformation are qualitatively similar to the stress-strain diagram except for the initial region of loading, where the effect of induced magnetoelastic anisotropy is displayed. At the stage of elastic strains, an unambiguous correlation between the coercive force measured on a minor hysteresis loop in weak fields and tensile stresses was discovered, thereby allowing the use of this parameter for evaluating the elastic stresses in articles from the 12ΓБ pipe steel, including in conditions of the influence of a hydrogen sulfide medium on this steel.

Influence of Hydrogen Sulfide in Fuel on Electric Power of Solid Oxide Fuel Cell

Terminal voltage, electric power density and overpotential were measured for the solid oxide fuel cell with gadolinium-doped ceria electrolyte (Ce0.8Gd0.2O1.9, GDC), 30 vol% Ni-GDC anode and Pt cathode using a H2 fuel or biogas (CH4 47, CO2 31, H2 19 vol %) at 1073 K. Addition of 1 ppm H2S in the 3vol % H2O-containing H2 fuel gave no change in the open circuit voltage (0.79 - 0.80 V) and the maximum power density (65 - 72 mW/cm2). Furthermore, no reaction between H2S and Ni in the anode was suggested by the thermodynamic calculation. On the other hand, the terminal voltage and electric power density decreased when 1 ppm H2S gas was mixed with the biogas. After the biogas with 1 ppm H2S flowed into the anode for 8 h, the electric power density decreased from 125 to 90 mW/cm2. The reduced electric power density was also recovered by passing 3 vol % H2O-containing H2 fuel for 2 h.

The influence of hydrogen sulfide on proton exchange membrane fuel cell anodes

The effect of hydrogen sulfide on proton exchange membrane fuel cell (PEMFC) anodes was studied by cyclic voltammetry (CV), potential steps and electrochemical impedance spectroscopy (EIS). The severity of the effect of H 2S varies depending on the H 2S concentration, current density and the cell temperature. The anode humidification does not impact the poisoning rate much when the anode is exposed to H 2S. The adsorption of H 2S on the anode is dissociative and this dissociation can produce adsorbed sulfur. The dissociation potential of H 2S was studied by potential steps, and the values of the dissociation potential are about 0.4 V at 90 °C, 0.5 V at 60 °C and 0.6 V at 30 °C, respectively. The adsorbed sulfur can be oxidized at a higher potential. During CV scans, two oxidation peaks for the adsorbed sulfur at 1.07 and 1.2 V were observed at 90 °C, however a single oxidation peak could be observed at 1.2 V at 60 °C and at 1.27 V at 30 °C. Application of EIS to a H 2S|H 2 half-cell shows that the charge transfer resistance increases when the anode is exposed to H 2S because of H 2S adsorption.

2-29.メタンの脱水素芳香族化反応(57)バイオガス由来のメタンガス直接改質における不純物の影響((7)天然ガス転換利用III,Session 2 天然ガス・メタンハイドレート等)

2-29.メタンの脱水素芳香族化反応(57)バイオガス由来のメタンガス直接改質における不純物の影響((7)天然ガス転換利用III,Session 2 天然ガス・メタンハイドレート等)

Effect of hydrogen sulfide on the iron dissolution rate in a sodium sulfate solution under natural aeration conditions

The influence of hydrogen sulfide (10–100 mg/1) on the Armco iron anodic dissolution in an aerated 0.17 M Na2SO4 solution is investigated. During a potentiostatic anodic polarization, the hydrogen sulfide introduction makes the current increase stepwise. The magnitude of the increase depends on the duration of preliminary anodic polarization, electrode potential, and hydrogen sulfide concentration. The anodic metal dissolution activation by hydrogen sulfide is explained by chemical conversion of the oxide-hydroxide passivating film into iron sulfide that is generated at the metal surface in the form of a porous film and does not hinder the electrode dissolution.

The influence of hydrogen sulfide on corrosion of iron under different conditions

Hydrogen sulfide (H 2S) can either accelerate or inhibit corrosion of iron under different experimental conditions. What H 2S has done to both the anodic iron dissolution and cathodic hydrogen evolution, in most cases, is to have a strong acceleration effect, causing iron to be seriously corroded in acidic medium, but H 2S can also have a strong inhibition on the iron corrosion under certain special conditions where H 2S concentration is below 0.04 mmol dm −3, pH value of electrolyte solution is within 3–5 and the immersion time of the clectrode is over 2 h. The inhibition effect of H 2S on the iron corrosion is attributed to formation of ferrous sulfide (FeS) protective film on the electrode surface. Moreover, the structure and composition of the protective film is closely related to H 2S concentration, pH of solutions and the immersion time of iron. Accordingly, the influence of the three factors on the inhibition effect is investigated in this paper by means of AC impedance technology together with the potentiostatic steady-state polarization. A probable reaction mechanism is proposed to interpret theoretically how H 2S inhibits the corrosion of iron.

Kinetic approach in the comparison of supported and unsupported ternary nickel-ruthenium-sulphur compounds in hydrotreating reactions

Unsupported and alumina-supported ruthenium sulphide and nickel-ruthenium sulphide catalysts were compared in hydrotreating reactions. A kinetic study for thiophene hydrodesulphurization indicated similarities in selectivities for unsupported and alumina-supported ruthenium sulphide samples, on the one hand, and for nickel-ruthenium sulphide samples, on the other hand. Such results led us to believe that the corresponding active phase was transferred over alumina. Moreover, the influence of hydrogen sulphide was stronger on the hydrodesulphurization reaction than on the hydrogenation reaction. Under the high hydrogen sulphide partial pressure used for the latter reaction, the alumina supported nickel-ruthenium-sulphur catalyst exhibited a very high hydrogenation activity compared with a commercial alumina-supported nickel-molybdenum catalyst.

The Influence of Hydrogen Sulfide on the Combustion of Methanol in a Stoichiometric Premixed Flame. Experimental and Numerical Studies

Abstract The kinetic mechanism for converting H2S to SO and S02 has been studied in a low-pressure (80 Torr) stoichiometric CH3OH-Air flame doped with H2S in the range up to 2.4%. The experimental measurements are compared with the predictions of a reduced and updated comprehensive chemical kinetic model including 23 species and 47 pairs of elementary reactions. The agreement between model and experiment is generally good except for H atom. Analysis of the sulfur reaction mechanism clearly shows the importance of reactions H2S + H = SH + H2, H2S + OH = SH + H20, SO + OH = SO2 + H, SO + O2 = SO2 + O and S + O2 = SO + O to describe the evolution of H2S, and SO and SO2 species.

Transformations of n-pentane in the presence of hydrogen sulfide on pentasils

1. The influence of hydrogen sulfide on the activity of H-TsVM in the aromatization of n-pentane was established. Under conditions of complete conversion (550°C, vmass=0.8 h−1 and H2S ∶ n-C5=3, molar), the yield of the C6-C14-aromatic hydrocarbons increases from 40 to 48%. 2. Increase in the molar ratio H2S ∶ n-C5 from 1.9 to 6 influences the selectivity of H-TsVM and leads to increase in the yield of C6-C7- and decrease in the yield of C9-C14-aromatic hydrocarbons.

Influence of IFKhANGAZ-1 inhibitor on crack growth in corrosion fatigue of steel in a hydrogen sulfide-containing medium

The authors present results of their investigation of the influence of hydrogen sulfide on crack growth in the corrosion fatigue of 32Kh3NMFA steel in a 3 percent NaCl solution and of the protective properties of the title inhibitor as well as its influence on the role of hydrogen embrittlement in corrosion fatigue crack propagation.

Improved method for separate determination of sulfur compounds in hydrocarbon gases

In order to eliminate the influence of hydrogen sulfide on the determination of mercaptan sulfur content, the authors propose that the single absorber solution (40% NaOH) should be replaced by two different solutions used in series: a 3% aqueous Na/sub 2/CO/sub 3/ solution for selective removal of the hydrogen sulfide, and a 40% aqueous NaOH solution for absorption of the mercaptans and residual hydrosulfide. The use of these two solutions can give a significant improvement in the accuracy of determination of the mercaptan sulfur concentration in gases.

On the detectability of H2S in Jupiter

The influence of hydrogen sulfide, a still-undetected key molecule for the Jovian atmospheric chemistry in the infrared spectrum, was investigated. Synthetic spectra including various vertical distribution profiles of H2S have been computed and compared with observational data for Jupiter in the 2- to 15-cm−1 and 1160- to 1200-cm−1 spectral ranges. No firm conclusion about the presence of H2S can be drawn from the latter spectral region because of large uncertainties in gaseous opacities. In the microwave range, H2S is found to be a possible candidate to explain the measurements. Constraints to its vertical distribution which would imply a significant supersaturation in the troposphere are derived. Physical and chemical processes involving H2S in the atmosphere are discussed in the light of this hypothesis.

Gravimetric microdetermination of alkoxy groups in sulphur containing compounds

A simple procedure for microgravimetric determination of alkoxy groups in sulphur-containing compounds has been developed. The influence of hydrogen sulphide formed in the reaction with hydriodic acid is removed by the use of a new solid scrubber filled with manganese dioxide.

Investigation of the corrosive influence of hydrogen sulfide on the metal of pumping-gear bars

The article describes the results of the experimental determination of the corrosion properties of 40C, 15NiMo, 20CrNi, and 36Mo17 steels in mineralized hydrogen sulfide solutions. It was concluded that steels 36Mo17 and 15NiMo are most suitable for service in H2S-bearing corrosive media.