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  • 1
    ISSN: 1432-072X
    Keywords: Thiobacillus intermedius ; Thiobacillus versutus ; Thiosulfate ; Polythionates ; Ion-pair chromatography ; Microcalorimetry ; Biofilm
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The growth of Thiobacillus (T.) intermedius strain K12 and Thiobacillus versutus strain DSM 582 on thiosulfate and tetrathionate was studied combining on-line measurements of metabolic activity and sulfur compound analysis. Most results indicate that T. intermedius oxidized thiosulfate via tetrathionate to sulfate. Concomittantly, sulfur compound intermediates like triand pentathionate were detectable. The formation is probably the result of highly reactive sulfane monosulfonic acids. The formation of tetrathionate allows the cells to buffer temporarily the proton excretion from sulfuric acid production. With T. versutus intermediate sulfur compounds were not detectable, however, sulfur was detectable. The possibility of a thiosulfate oxidation via dithionate, S2O inf6 sup2- , is discussed. The on-line measurement of metabolic activity by microcalorimetry enabled us to detect that cells of T. intermedius adhere to surfaces and produce a biofilm by a metabolic process whereas those of T. versutus fail to do so. The importance of the finding is discussed.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 153 (1990), S. 432-437 
    ISSN: 1432-072X
    Keywords: Chromatium vinosum ; Phototrophic bacteria ; Polysulfides ; Polythionates ; Elemental sulfur ; Sulfur globules ; Ion chromatography ; HPLC
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cultures of Chromatium vinosum, devoid of sulfur globules, were supplemented with sulfide and incubated under anoxic conditions in the light. The concentrations of sulfide, polysulfides, thiosulfate, polythionates and elemental sulfur (sulfur rings) were monitored for 3 days by ion-chromatography and reversed-phase HPLC. While sulfide disappeared rapidly, thiosulfate and elemental sulfur (S6, S7 S8 rings) were formed. After sulfide depletion, the concentration of thiosulfate decreased fairly rapidly, but elemental sulfur was oxidized very slowly to sulfate. Neither polysulfides (S x 2− ), polythionates (SnO 6 2− , n=4–6), nor other polysulfur compounds could be detected, which is in accordance with the fact that sulfide-grown cells were able to oxidize polysulfide without lag. The nature of the intracellular sulfur globules is discussed.
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  • 3
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Heteroatom Chemistry 2 (1991), S. 633-641 
    ISSN: 1042-7163
    Keywords: Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The vapor phase structure of (CH3O)2S [1] has been investigated by electron diffraction and ab initio MO calculations, which both result in a C2 symmetry for the most stable geometry, the Cs conformer being less stable by about 12 kJ/mol. The torsional barrier for rotation about one SO bond was calculated as 37 kJ/mol (trans barrier). The geometrical parameters (electron diffraction) of the C2 conformer are: dSO = 162.5(2), dCO = 142.6(3), dCH = 110.5(7) pm angles OSO = 103(1)°, SOC = 115.9(4)°, HCH = 109(1)°, torsional angle COSO = 84(3)°. Geometrical data calculated with 6-31G* basis set agree well with the diffraction data; calculated dipole moments 1.1 D (C2) and 3.3 D (Cs).The infrared spectrum of gaseous (CH3O)2S and the Raman spectra of liquid and solid (CH3O)2S are reported and have been almost fully assigned to the 27 fundamental vibrations.
    Additional Material: 4 Ill.
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 1999 (1999), S. 2057-2061 
    ISSN: 1434-1948
    Keywords: Sulfur ; Sulfanes ; Acidity ; Ab initio MO calculations ; Hyperconjugation ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The gas-phase acidities ΔGacid(298 K) of the sulfanes H2Sn (n = 1-4) have been calculated by ab initio molecular orbital theory using the G2 and G2(MP2) methods, which were applied to the geometries of lowest energy. The results show that the higher sulfanes are surprisingly strong proton donors. The acidities (in kJ mol-1) are as follows: H2S (1444), H2S2 (1406), H2S3 (1370), H2S4 (1347). The latter three values may be compared to those of other strong Brønsted acids like gaseous HNO2 (1396), HCl (1371), and HBr (1332). The monoanions HSn- exhibit an interesting bond length distribution as a consequence of the charge delocalization by hyperconjugation, which in turn may be responsible for the high acidities of the sulfanes.
    Additional Material: 3 Ill.
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  • 5
    ISSN: 1434-1948
    Keywords: Sulfur ; Titanium ; Zinc ; Polysulfido complexes ; Sulfur heterocycles ; Polysulfides ; Polysulfanes ; Sulfenyl chlorides ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The preparation of seven novel organic polysulfanes is reported. Bis(n-octyl)heptasulfane R2S7 1 is formed upon reaction of RSCl with [Cp2TiS5], while the corresponding nonasulfane R2S9 2 is obtained by reaction of RSSCl with [Cp2TiS5]. The bis(n-octyl)pentasulfane R2S5 3 is obtained from RSCl and [(Cp′2TiCl)2S3] by transfer of the S3 ligand at 20 °C. The new alkyl polysulfanes 1-3 have been obtained in quantitative yields. They are liquids at 20 °C, having freezing points below -50 °C, but do not form mesogenic phases. Reactions of [Cp2TiS5] with 2-naphthyl- and 4-chlorophenyl sulfenyl chloride furnish the corresponding heptasulfanes 4 and 5, respectively, which are solids at 20 °C. 1,2-Benzodisulfenyl chloride C6H4(SCl)2 reacts with [(Cp′2TiCl)2S3] to give the known 1,2,3,4,5-benzopentathiepin C6H4S5 6, with [Cp2TiS5] to give the novel 1,2,3,4,5,6,7-benzoheptathionin C6H4S7 7, and with [(TMEDA)ZnS6] to give the novel 1,2,3,4,5,6,7,8-benzooctathiecin C6H4S8 8. The cyclic polysulfanes 6-8 are solids at 20 °C and have been recovered in yields of 60-83%. The orthorhombic structure of 1,2-C6H4S7 has been investigated by single-crystal X-ray diffraction analysis. The molecules are found to be located at sites of Cs symmetry and the motif of the C2S7 heterocycle is +-+-+-+-, with the torsion angle of zero at the carbon-carbon bond. The three internuclear SS distances measure 205.0(1), 203.7(1), and 205.7(1) pm.
    Additional Material: 4 Ill.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 2000 (2000), S. 617-624 
    ISSN: 1434-1948
    Keywords: Sulfur oxo acids ; Acidity ; Ab initio calculations ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The gas-phase acidities of the most stable conformations of nine sulfur oxo acids were determined by ab initio MO calculations at the CBS-Q, G2(MP2), and G2 levels of theory. The most accurate G2 results are as follows (ΔG°298 of the deprotonation reaction in kJ mol-1): H-S-O-H 1468, H-S-O-H 1449, (HO)2S 1426, H-S(=O)OH 1406, H2S/O 1394, H-S(=O)OH 1361, (HO)2S/O 1324, H2S(=O)2 1321, H2O→S 1294, H-S(=O)2OH 1287, H-S(=O)2OH 1279, (HO)2S(=O)2 1268. These values are in excellent agreement with the few experimental data that can be considered reliable. For molecules of analogous structure, the acidity increases with increasing oxidation number of the sulfur atom. While sulfenic acid, HSOH, is as weak an acid as HOCl, sulfurous acid, (HO)2SO, is as strong a proton donor as nitric acid, HNO3, and sulfonic acid, HS(O)2OH, is even stronger than hydrogen iodide, HI, surpassed only by sulfuric acid, H2SO4. These results are of relevance to phenomena such as acid rain and aerosol formation in the earth′s atmosphere.
    Additional Material: 2 Ill.
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 360 (1968), S. 143-150 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: By a new technique the CCl3 radical is isolated from the gaseous state at -190°C. Its preparation may be represented by the reactions mentioned above. As CCl3Br when treated with bromine, and also as the dimer C2Cl6. Its IR spectrum shows a strong band v3 (CCl3) at 895 cm-1 (along with a satellite at 869 cm-1), indicating that very probably the molecule belongs to the symmetry group D3h.
    Notes: Es wird eine Untersuchungstechnik beschrieben, mit deren Hilfe das Radikal CCl3 in der Gasphase (0,05 Torr) dargestellt und bei -190°C isoliert und spektroskopisch nachgewiesen werden kann. Zur Darstellung dienen die Reaktionen \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm CCl}_{\rm 4} + {\rm Ag}\,\,\,\,\,\, \to {\rm CCl}_{\rm 3} + {\rm AgCl}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\rm bei}\,{\rm 600}\,\,^ \circ {\rm C} $$\end{document}\documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm CCl}_{\rm 4} + {\rm AgBr} \to {\rm CCl}_{\rm 3} + {\rm Br} + {\rm AgCl}\,\,\,\,\,\,\,\,{\rm bei 600 }^ \circ {\rm C} $$\end{document}\documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm CCl}_{\rm 4} + {\rm AgJ}\,\,\,\,\, \to {\rm CCl}_{\rm 3} + {\rm J} + {\rm AgCl}\,\,\,\,\,\,\,\,\,\,\,{\rm bei 600}\,^ \circ {\rm C} $$\end{document} CCl3 wird identifiziert durch die IR-Absorptionen v3 (CCl3) = 895 cm-1 und v3 (13CCl3) = 869 cm-1, durch die Rekombination zu C2Cl6 und die Reaktion mit Brom zu CCl3Br. Die wahrscheinliche Symmetrie des CCl3 ist die der Punktgruppe D3h.
    Additional Material: 3 Ill.
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 476 (1981), S. 171-178 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: X-Ray Structural Analyses of Cyclododecasulfur (S12) and Cyclododecasulfur-1-Carbon-disulfide (S12 · CS2)S12 · CS2 crystallizes in space group R&3macr;m-D3d5 with hexagonal lattice constants a = 1066.8(3), c = 1155.1(4) pm, Z = 3, dcalc. = 2.04 g · cm-3. The S12 molecules occupy sites of D3d symmetry with bond distance (dss) of 205.4(1) pm, bond angles (α) of 105.80(5) and 106.65(6)º and torsional angle (τ) of 87.20(7)º. The CS2 molecule interacts only very weakly with the S12 units.S12 crystallizes in space group Pnnm-D2h12 with lattice constants a = 472.5(2), b = 910.4(3), c = 1453.2(3) pm, Z = 2, dcalc = 2.045 g · cm-3. The molecules with mean parameters d = 205.2 pm, α 106.6º, τ 88.0º occupy sites of C2h symmetry.
    Notes: S12 · CS2 kristallisiert in der trigonalen Raumgruppe R&3macr;m-D3d5 mit den hexagonalen Gitterkonstanten a = 1066,8(3), c = 1155,1(4) pm, Z = 3, dber. = 2,04 g · cm-3. Die S12-Moleküle besetzen Lagen der Symmetrie D3d mit dem Kernabstand (d) 205,4(1) pm, den Valenzwinkeln (α) 105,80(5) und 106,65(6)º und dem Torsionswinkel (τ) 87,20(7)º. Das CS2-Molekül ist nur sehr locker gebunden.S12 kristallisiert in der orthorhombischen Raumgruppe Pnnm - D2h12 mit den Gitterkonstanten a = 472,5(2), b = 910,4(3), c = 1453,2(3) pm, Z = 2, dber. = 2,045 g · cm-3. Die Moleküle besetzen Lagen der Symmetrie C2h, die mittleren Molekülparameter sind: dss = 205,2 pm, α = 106,6º, τ = 88,0º.
    Additional Material: 2 Ill.
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 478 (1981), S. 139-155 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Molecular Composition of Liquid Sulfur. Part 1: Critical Review of the LiteratureThe literature concerning the molecular composition of liquid sulfur is critically reviewed. Experimental data of different authors are compared and in some cases corrected and reinterpreted. At the melting point after equilibration the liquid contains besides S8 5% (at 150°C: 8%) π sulfur, while polymeric μ sulfur rises from 1% at 135°C to a maximum of 56% at 250-300°C. The heat of formation of Sπ amounts to 22 kJ/mol, the formation of Sμ is also endothermic. It is however concluded that the exact molecular nature of both π and μ sulfur is unknown and both substances are likely to be mixtures. It is shown that all published theories concerning the polymerization of S8 are in disagreement with well established experimental facts and therefore must be considered unsatisfactory if not wrong.
    Notes: Die Literatur über die molekulare Zusammensetzung wird zusammenfassend und kritisch dargelegt; experimentelle Angaben verschiedener Autoren werden verglichen, in einigen Fällen korrigiert und neu interpretiert. Danach besteht Schwefel beim Schmelzpunkt nach Gleichgewichtseinstellung neben S8 zu 5% (bei 150°C zu 8%) aus π-Schwefel, während der Gehalt an polymerem μ-Schwefel von 1% bei 135°C auf maximal 56% bei 250-300°C ansteigt. Die Bildungsenthalpie von Sπ beträgt 22 kJ/mol, die von Sμ ist ebenfalls positiv. Die genaue molekulare Zusammensetzung von π- und μ-Schwefel ist jedoch unbekannt, wahrscheinlich handelt es sich um Mischungen. Die bisher publizierten Theorien über die Polymerisation von S8 zu Sμ stehen im Widerspruch zu gesicherten experimentellen Tatsachen und sind daher unbefriedigend oder gar falsch.
    Additional Material: 2 Ill.
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 478 (1981), S. 156-176 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Molecular Composition of Liquid Sulfur. Part 2: Qualitative Analysis and Preparation of S7, S12, α-S18, and S20 from S8Raman spectra of sulfur melts (115-300°C), of quenched melts and of CS2 extracts of quenched melts show besides S8 the presence of S6 and S7. Formation of S7 from S8 at 120°C takes more than 8 h; the S7 equilibrium concentration increases with temperature. Pure crystalline S7, S12, α-S18 and S20 are prepared on a preparative scale by fractional extraction, crystallization, flotation and precipitation of quenched sulfur melts. Also a mixture of larger rings (Sx; x̄ = 25) has been isolated. Infrared and Raman spectra of α-S18, S20 and Sx are reported.
    Notes: Ramanspektren von heißen Schwefelschmelzen (115-300°C), von abgeschreckten Schmelzen und von CS2-Extrakten der abgeschreckten Schmelzen zeigen die Anwesenheit von S6 und S7 neben S8. Die Bildung von S7 aus S8 dauert bei 120°C mehr als 8 h; die S7-Gleichgewichtskonzentration steigt mit der Temperatur. Durch fraktionierte Extraktion, Kristallisation, Flotation und Fällung konnten aus abgeschreckten Schwefelschmelzen S7, S12, α-S18 und S20 in reiner Form und in präparativem Umfang gewonnen werden. Außerdem wurde ein Gemisch großer Ringe Sx mit x̄ = 25 als harzartige Substanz isoliert. IR- und Ramanspektren von α-S18, S20 und Sx werden mitgeteilt.
    Additional Material: 10 Ill.
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