ChemInform Abstract: INORGANIC SULFUR COMPOUNDS OF MOLYBDENUM AND TUNGSTEN. THEIR PREPARATION, STRUCTURE, AND PROPERTIES

1979 ◽  
Vol 10 (6) ◽  
Author(s):  
G. A. TSIGDINOS
Keyword(s):  
Sulfur Compounds ◽  
Structure And Properties ◽  
Inorganic Sulfur ◽  
And Tungsten

scholarly journals Anaerobic Respiration of Elemental Sulfur and Thiosulfate by Shewanella oneidensis MR-1 Requires psrA, a Homolog of the phsA Gene of Salmonella enterica Serovar Typhimurium LT2

2009 ◽  
Vol 75 (16) ◽  
pp. 5209-5217 ◽  
Author(s):  
Justin L. Burns ◽  
Thomas J. DiChristina
Keyword(s):  
Gene Cluster ◽  
Salmonella Enterica ◽  
Elemental Sulfur ◽  
Shewanella Oneidensis ◽  
Anaerobic Respiration ◽  
Sulfur Cycle ◽  
Sulfur Compounds ◽  
Electron Acceptors ◽  
Inorganic Sulfur ◽  
Serovar Typhimurium

ABSTRACT Shewanella oneidensis MR-1, a facultatively anaerobic gammaproteobacterium, respires a variety of anaerobic terminal electron acceptors, including the inorganic sulfur compounds sulfite (SO3 2−), thiosulfate (S2O3 2−), tetrathionate (S4O6 2−), and elemental sulfur (S0). The molecular mechanism of anaerobic respiration of inorganic sulfur compounds by S. oneidensis, however, is poorly understood. In the present study, we identified a three-gene cluster in the S. oneidensis genome whose translated products displayed 59 to 73% amino acid similarity to the products of phsABC, a gene cluster required for S0 and S2O3 2− respiration by Salmonella enterica serovar Typhimurium LT2. Homologs of phsA (annotated as psrA) were identified in the genomes of Shewanella strains that reduce S0 and S2O3 2− yet were missing from the genomes of Shewanella strains unable to reduce these electron acceptors. A new suicide vector was constructed and used to generate a markerless, in-frame deletion of psrA, the gene encoding the putative thiosulfate reductase. The psrA deletion mutant (PSRA1) retained expression of downstream genes psrB and psrC but was unable to respire S0 or S2O3 2− as the terminal electron acceptor. Based on these results, we postulate that PsrA functions as the main subunit of the S. oneidensis S2O3 2− terminal reductase whose end products (sulfide [HS−] or SO3 2−) participate in an intraspecies sulfur cycle that drives S0 respiration.

Engineering Structure and Properties of Materials Used as a Matrix in Diamond Impregnated Tools / Kształtowanie Struktury I Własnosci Materiałów Stosowanych Jako Osnowa W Narzedziach Metaliczno-Diamentowych

2013 ◽  
Vol 58 (1) ◽  
pp. 5-8 ◽  
Author(s):  
J. Borowiecka-Jamrozek
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Structure And Properties ◽  
Hot Press ◽  
Properties Of Materials ◽  
The Mean ◽  
Materials Used ◽  
Hot Press Process ◽  
Scanning Electron ◽  
And Tungsten

The paper presents mechanical properties of materials used as matrices in diamond impregnated tools. Several powder metallurgy materials were manufactured by the hot press process from various combinations of cobalt (Co SMS, Co Extrafine, Co 400mesh), carbonyl iron (Fe CN) and tungsten (WP30) powders. After consolidation the specimens were tested for density, hardness and tensile properties. The fracture surfaces and materials’ microstructure were observed using the Jeol JSM- 5400 scanning electron microscope and the Leica DM4000 light microscope. The main objective of the work was to determine the effects of the mean particle size of cobalt as well as additions of iron and tungsten on properties of the as-consolidated material.

COS and C3S2: The discovery and chemistry of two important inorganic sulfur compounds

Polyhedron ◽  
1985 ◽  
Vol 4 (5) ◽  
pp. 775-781 ◽  
Author(s):  
Mihály T. Beck ◽  
George B. Kauffman
Keyword(s):  
Sulfur Compounds ◽  
Inorganic Sulfur
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