Use of an ion-selective membrane electrode for the determination of the active components in intestopan

The conditions for the determination of broxyquinoline and brobenzoxaldine, the active components of "Intestopan", by use of ion-selective membrane electrodes are described. Broxyquinoline is determined directly through precipitation with CuSO(4), and brobenzoxaldine is first hydrolysed in alkaline solution and the product precipitated with CuSO(4). In both cases the CuSO(4) in excess is determined by potentiometric titration at pH 5.6 with EDTA, a Cu(2+)-selective electrode being used for end-point detection.     

Coordination polymers and a dinuclear complex constructed from zinc(II) ions and fluorescein: iodine adsorption and optical properties

Abstract

1-D coordination polymers, ¹_∞[Zn(fl)₂]·2EtOH and ¹_∞[Zn(fl)₂]·2MeOH, and a dinuclear complex, [{Zn(fl)₂}₂(dienpip)]·4H₂O·4EtOH (dienpip?= N,N′-bis(2-aminoethyl)piperazine), were obtained using Zn(II) ions and fluorescein anions (fl). Thermal analysis shows stability of the polymers after solvent removal up to more than 400?°C. Crystallization solvent molecules were removed under reduced pressure with the preservation of the polymeric structure, ¹_∞[Zn(fl)₂]. Desolvated crystals were exposed to I₂ vapors and the crystal structure determination by X-ray diffraction confirmed the presence of I₂ molecules in the channels generated in crystals by the metal-organic framework. The iodine content, evaluated by X-ray diffraction, corresponds to the overall formula ¹_∞[Zn(fl)₂]·0.3I₂. The optical properties of the coordination polymers and the dinuclear complex have been investigated.     

On the Stability of Certain Spin Models in 2+1 Dimensions

In this paper we prove large-data local stability theorems for several spin-field models in two dimensions, both in the focusing case (spherical target) and the defocusing case (hyperbolic target).     

Categorification and Group Extensions

We review several known categorification procedures, and introduce a functorial categorification of group extensions (Section 4.1) with applications to non-Abelian group cohomology (Section 4.2). The obstruction to the existence of group extensions (Section 4.2.4, Equation (9)) is interpreted as a coboundary condition (Proposition 4.5).     

Redheffer's theorem revisited

Based on the Ben Artzi-Gohberg result concerning the equivalence between the invertibility of theL ²-operator and the exponential dichotomic evolution defined byA(t), the time-varying counterpart of the Redheffer theorem is considered under relaxed conditions.     

Interaction of propylene with a promoted Bi?Mo catalyst as determined from conductivity data

A new cell is described which allows simultaneous measurement of the electrical and catalytic properties of a promoted Bi–Mo catalyst. The electrical resistance data show that the interaction of propylene with the catalyst starts at 310 °C.

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, Bi–Mo. , 310°C.

     

Hochschild homology of a topological algebra and formal smoothness

In this note we will prove that the Hochschild homology algebra of a topological algebra and its universally complete differential algebra are isomorphic in the case of a formally smooth morphism