Common Fixed Points of Commuting Mappings in 2-Metric Spaces and an Application

We prove some interior regularity properties of the displacements and stresses for a quasistatic elasto-visco-plastic modell in continuum mechanics.     

Electrical deviations from Matthiessen's rule in A Ag:Au alloy

Electrical resistivity of Ag:0.29 at % Au alloy has been measured and explained theoretically with the aim of understanding the deviations from Matthiessen's rule. The anisotropy in the electron-phonon interaction, the recoil of the impurity, mass-changes, nearest neighbour radial and angular force-constant-changes and Debye-Waller factors have been taken into consideration.     

Microdetermination of indoles with N-bromoacetamide in acetic acid medium

Summary A titrimetric method for the microdetermination of indole and its derivatives withN-bromoacetamide is described. It has been observed thatN-bromoacetamide brominates the compound containing indole nucleus in the presence of acetic acid. The usual reaction time is 15 minutes and the reaction is carried out at room temperature. The relative errors are less than ±1.5% at the mg level.

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Zusammenfassung Die maßanalytische Bestimmung von Indol und seinen Derivaten mitN-Bromacetamid wurde beschrieben. Dieses Reagens bromiert in Gegenwart von Essigsäure indolhältige Verbindungen innerhalb 15 min bei Zimmertemperatur. Der rel. Fehler ist geringer als ±1,5%.

     

Effect of metal cationization on the tandem mass spectra of glycosyl dithioacetals

The effect of metal cationization on the tandem mass spectra of glycosyl dithioacetals of glucose, mannose, galactose, rhamnose, arabinose and xylose was studied by electrospray ionization mass spectrometry under ammonium and metal (Li, Na, Ag and Cu) ion cationization conditions. The ammonium-cationized glycosyl dithioacetals fragment by loss of ammonia followed by either two molecules of EtSH or one molecule of EtSH and one molecule of H2O. Lithium cationization leads to additional eliminations such as EtSEt and EtSSEt and C-C cleavages. Elimination of EtSH is not observed under sodium cationization. Silver cationization, on the other hand, leads to additional fragmentations involving the elimination of silver as AgOH and AgSEt. Copper cationization results in adducts where copper has undergone a change of oxidation state from II to I. Li+, Ag+ and Cu+ cationization seem to favour cyclization resulting in elimination of EtSH. However, the mechanisms seem to be differently affected by different metal ions. Li+ and Ag+ cationization appear to be non-specific and favour cyclization involving C2-, C4- and C5-hydroxyl hydrogens, whereas Cu+ cationization seems to favour cyclization involving C4-hydroxyl hydrogen.     

Chiral SU(4) × SU(4) breaking: masses and decay constants of charmed hadrons

The (4, 4*) ⊕ (4*, 4) model of broken chiral SU (4) × SU (4) symmetry has been used to calculate the third-order coupling constants involving charmed and ordinary pseudoscalar mesons. These coupling constants are exploited to derive some interesting new relations among the masses and decay constants of these charmed particles. Using the known masses and decay constants as inputs, we exploit these relations to predict:F _D = −1·41F _π ,F _F = −1·13F _π ,F _D/F_F = 1·25,m(D _s) = 1·43 GeV,m(F _s) = 1·39 GeV andm(K _s) = 1·02 GeV.