Alkali polysulfides dissolve in EPD-solvents (e.q. dlmethylformarnide, dimethylsulfoxide, and hexamethylphosphoramide) to give dee~ qreen, blue and carmine red solutions. Vis. and u.v. scectronhotornetric as well as e.s.r. s~ectrometric investigations showed that normal polysulfides Sx -with different chain lenqth are the carriers of the yellow and red color, whereas the radical ion s 3 -is the blue species, which gives clear blue solutions or, if it is mixed with polysulfide anions with x<6 or x>6, qreen or carrnine red. u.v. and e.s.r. spectra point to the existence of two further radical ions s2-(yellow) and s4-(red) in EPD-solvents. The behaviour of polysulfides in these solvents can be understood by assuminq that anions are only poorly solvated due to dipole shieldin~ of the solvent rnolecules.

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Durch VIS/UV‐, IR‐, 15N‐NMR‐ und ESR‐spektrometrische Messungen, sowie chromatographische und Gas‐Analysen ist der Mechanismus der Titelreaktion aufgeklärt worden. Der Verlauf der komplexen Umsetzung und die groβe Anzahl von Produkten — Distickstoffoxid, Stickstoffmonoxid, Natriumthiosulfat, Sulfat, Polysulfide, Polythionate, Nitrat — können mit der Annahme erklärt werden, daß zunächst Natriumperthionitrate NaSxNO2 entstehen, die sich in Distickstoffoxid und Thiosulfat zersetzen, oder auch mit Nitrit zu Nitrat und Perthionitrit, NaSSNO, reagieren, das reversibel in Stickoxid und Natriumtrisulfid(1—) dissoziiert. (Bezüglich der Einzelheiten der konkurrierenden und aufeinander folgenden Reaktionsschritte vgl. Tab. 2.) Der charakteristische Farbwechsel während der Titelreaktion von blau‐grün über braun nach orangerot ist auf die Entstehung zweier Farbträger zurückzuführen: S3− (blau, λmax = 620 nm, g = 2,029) und ONSS− (rot, λmax = 448 nm, δ(15N) = 334 ppm, bez. auf K15NO3).

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PurposeThis paper seeks to describe the evolution of SAP implementation methodologies and tools, in particular, Value SAP, with a focus on the Accelerated SAP (ASAP) implementation methodology and its evolution as a part of SAP's new Solution Manager tool.Design/methodology/approachThe general approach is more focused on monitoring and managing an ongoing SAP implementation project using an enterprise solution architecture. Three options are explored.FindingsFinds that one option supports end‐to‐end business process management – other options can be managed, but with cost and risk.Originality/valueThis paper has reviewed the latest developments in SAP implementation methodologies from a management orientation. The issues in this paper are often taken for granted by researchers, so it is hoped that the focus on these issues will elevate interests in pursuing some of the unanswered questions.