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For arbitrary subsets X and Y of the real line with at least two points, let BV(X) (resp. BV(Y)) be the Banach space of all functions of bounded variation on X (resp. Y) endowed with the natural norm ‖ ⋅ ‖ ∞ + V (⋅) , where ‖ ⋅ ‖ ∞ and V (⋅) denote the supremum norm and the total variation of a function, respectively. We show that the set of all surjective linear isometries from BV(X) onto BV(Y) is topologically reflexive. Among the consequences, it is also proved that the set of all isometric reflections, and the set of all generalized bi-circular projections on BV(X) are topologically reflexive. [ABSTRACT FROM AUTHOR]

In the present study, a novel magnetic carbon nanotube functionalized by chlorosulfonicacid (Fe3O4‐CNT‐SO3H) with nanotube morphology decorated by the spherical nanoparticles was prepared, characterized and introduced as a retrievable magnetic heterogeneous nanocatalyst for green synthesis a variety of 2‐(1H‐tetrazole‐5‐yl) acrylonitrile via multicomponent domino Knoevenagel condensation/ 1,3‐dipolar cycloaddition reaction between aromatic aldehydes, malononitrile, and sodium azide under solvent free conditions. The catalyst was magnetically separated from the reaction system by an outer magnetic force and recycled up to five runs without a remarkable loss in its efficiency. The as‐preparedacidic magnetic nanocomposite was characterized by different techniques inclusive Fourier transform infrared, thermogravimetric analysis, energy dispersive X‐ray, field emission scanning electron microscopy, X‐ray diffraction, vibrating sample magnetometry, CHNS elemental analysis, and acid‐base titration. Easy workup, affordability, elimination of volatile and toxic solvents, and high yield of products are some merits of this protocol. [ABSTRACT FROM AUTHOR]

In this paper we study nonlinear diameter preserving mappings defined between function spaces and obtain generalizations of, basically, all known results concerning diameter preservers. In particular, we give a complete description for algebras of continuously differentiable functions, (little) Lipschitz algebras and dense function spaces. [ABSTRACT FROM AUTHOR]