Sodium sulfide

About: Sodium sulfide is a research topic. Over the lifetime, 2851 publications have been published within this topic receiving 27733 citations. The topic is also known as: disodium sulfide.

Superior one-pot synthesis of a doped graphene oxide electrode for a high power density supercapacitor

Abstract: In this work, we report the synthesis of sulfur-doped reduced graphene oxide (S-rGO) using sodium borohydride (NaBH4) and sodium sulfide (Na2S) by a facile one-pot approach via refluxing in deionised water. The undoped rGO chemical structure is partially reduced by NaBH4, whereas the addition of a small amount of Na2S with NaBH4 resulted in a better reduction of rGO. XPS analysis confirmed the successful doping of sulfur and Raman spectroscopy verified the increased defect density. The S-rGO electrode exhibits good power density (3202 W kg−1) with increased specific capacitance (392 F g−1) and cyclic stability (91%, 2000 cycles) in 1 M Na2SO4 aqueous electrolyte. The obtained results suggest that the simple tuning of the graphene oxide structure using Na2S with NaBH4 enhances the above properties. Moreover, this method is facile and allows the easy reproduction of bulk quantities of materials for use in commercial applications.

Reactions of benzene oxide with thiols including glutathione

Abstract: S-Phenylmercapturic acid is a minor metabolite of benzene used as a biomarker for human benzene exposures The reaction of intracellular glutathione with benzene oxide-oxepin, the initial metabolite of benzene, is presumed to give 1-(S-glutathionyl)-cyclohexa-3,5-dien-2-ol, which undergoes dehydration to S-phenylglutathione, the precursor of S-phenylmercapturic acid To validate the proposed route to S-phenylglutathione, reactions of benzene oxide-oxepin with glutathione and other sulfur nucleophiles have been studied The reaction of benzene oxide with an excess of aqueous sodium sulfide, followed by acetylation, gave bis-(6-trans-5-acetoxycyclohexa-1,3-dienyl)sulfide, the structure of which was proved by X-ray crystallography Reactions of benzene oxide-oxepin in a 95:5 (v/v) mixture of phosphate buffer in D2O with (CD3)2SO were monitored by 1H NMR spectroscopy In the absence of glutathione, the half-life of benzene oxide-oxepin was ca 34 min at 25 degrees C and pD 70 The half-life was not affected in the range of 2-15 mM glutathione in the presence and absence of a commercial sample of human glutathione S-transferase (at pH 70, 80, 85, or 100) The adduct 1-(S-glutathionyl)-cyclohexa-3,5-diene-2-ol was identified in these reaction mixtures, especially at higher pH, by mass spectrometry and by its acid-catalyzed decomposition to S-phenylglutathione Incubation of benzene oxide with N-acetyl-L-cysteine at 37 degrees C and pH 100 and subsequent mass spectrometric analysis of the mixture showed formation of pre-S-phenylmercapturic acid and the dehydration product, S-phenylmercapturic acid The data validate the premise that benzene oxide-oxepin can be captured by glutathione to give (1R,2R)- and/or (1S,2S)-1-(S-glutathionyl)-cyclohexa-3,5-dien-2-ol, which dehydrate to S-phenylglutathione The capture is a relatively inefficient process at pH 7 that is accelerated at higher pH These studies account for the observation that the metabolism of benzene is dominated by the formation of phenol The pathway leading to S-phenylmercapturic acid is necessarily minor on account of the low efficiency of benzene oxide capture by glutathione at pH 7 vs spontaneous rearrangement to phenol

Effects of Organic-Rich Sediment and Below-Ground Sulfide Exposure on Submerged Macrophyte, Hydrilla verticillata

Abstract: The effects of organic-rich sediment and sulfide exposure on Hydrilla verticillata were investigated. The organic richness of sediment was simulated by adding sucrose into sediments, and sulfide exposure was conducted by adding sodium sulfide to plant roots. The length, biomass and density of shoot reduced in the sucrose-amended sediments, and the largest reduction occurred in the highest 1.0% addition treatment by 84.2%, 56.7% and 92.4%, respectively. However, the 0.1% addition treatment stimulated the growth of root. The effects of below-ground sulfide exposure on the physiological activities of H. verticillata were determined by adding sulfide to the below-ground tissue. Significantly inhibitory effects of sulfide were observed on plant photosynthesis, root carbohydrate and nitrogen synthetic reserves. The net photosynthetic rates, soluble carbohydrate and soluble protein contents in root were reduced by 104%, 71.8% and 49.8%, respectively, in the 0.6 mM sulfide treatment.

Process for the removal of metals, in particular heavy metals, from waste water

Abstract: Process for the removal of metals, in particular heavy metals, from waste water in the form of their sulfide by mixing the waste water with a water soluble sulfide. According to the invention the metal containing waste water is thoroughly mixed with the water soluble sulfide at a suitable pH in a reactor of the fluidized bed type, which is provided with an appropriate bed material, on which the metal sulfide crystallizes out, whereby the thus obtained bed material provided with crystalline metal sulfide is removed from and new bed material is added to the reactor from time to time. Usually as water soluble sulfide an alkali metal sulfide or alkali metal hydrogen sulfide or ammonium sulfide or FeS is used, whereas the use of sodium sulfide, sodium hydrogen sulfide, potassium sulfide or potassium hydrogen sulfide is preferred. According to the present process a.o. the following metals: Ni, Sr, Zn, Cu, Fe, Ag, Pb, Cd, Hg, Co, Mn, Te, Sn, n, Bi or Sb may be removed.