Commutativity of some Archimedean ordered algebras

In this paper, using derivation theory, we present some results concerning the automatic order boundedness of band preserving operators on Archimedean semiprime \(f\) -algebras. Finally, inspired by the proof of Bernau and Huijsmans (Math Proc Camb Philos Soc 107:287–308, 1990), we give necessary and sufficient conditions for Archimedean lattice-ordered algebras to be commutative.     

Hindered Rotation in Some Organic Dithiocarbamates

Abstract

Hindered rotation in alkyldithiocarbamates of the type RR′NC(= S)SR″ [R, R′, R″ = Me, Me, Et (1); PhCH₂, Me, Et (2); PhCH₂, H, Et (3); PhCH₂, H, Me (4) and O(CH₂CH₂)₂, Et (5)′ has been investigated using variable-temperature ¹H NMR spectroscopy in CDCl₃, C₆D₆, and DMSO-d₆ solutions. Rotational parameters were calculated by the coalescence temperature method. Nitrogen substituent effects on the free energy of activation and on the equilibrium constant of unsymmetrical conformers at room temperature are discussed.     

Electrical conductivity investigation of diluted potassium chloride solutions in binary mixture triethylamine-water near its consolute point

The binary liquid mixture of triethylamine + water (TEA-W) has a lower consolute point at a critical composition of 32.27 mass % triethylamine. Starting at a temperature within the one-phase region, the electrical conductivity of a sample of this mixture with addition of (K⁺, Cl⁻) ions was measured and found to be accurately described by the Vogel-Fulcher-Tammann (VFT) law. Before that, for the pure system, in a temperature range ΔT = T_c − T < 2 °C where T_c is the critical temperature, the electrical conductivity (σ) exhibits a monotonous deviation from the VFT behaviour. This anomaly is finite at T_c. The asymptotic behaviour of the electrical conductivity anomaly is described by a power law t^1−α, where t is the reduced temperature |(T−Tc)/Tc| and α is the critical exponent of the specific heat anomaly at constant pressure. For the electrolyte mixtures, by combining the viscosity and the electrical conductivity data, the value of the computed Walden product has been determined and the salt dissociation degrees as well as the Debye screening length have been estimated.     

ChemInform Abstract: Crystal Structure and Spectroscopic Studies of LiNH4(H2PO4)2 — A New Solid Acid in the LiH2PO4—NH4H2PO4 System.

LiNH₄(H₂PO₄)₂ is prepared from an equimolar aqueous mixture of NH₄H₂PO₄ and LiH₂PO₄ by slow evaporation at 25 °C.