Composite materialis based on propylene and modified Na +-montmorillonite N, N-diallylacrilamide

ON COMPOSITE n FOR WHICH φ ( n ) \ n - 1 , II

The problem of whether there exists a composite n for which φ(n) \ n — 1 (φ is Euler's function) was first posed by D. H. Lehmer in 1932 and still remains unsolved. In this paper we prove that the number of such n not exceeding x is O(x(logx)). We also prove that any such n with precisely K distinct prime factors is necessarily less than K. There are appropriate generalizations of these results...

Characterization and optimization of a chromatographic process based on ethylenediamine-N,N,N',N'-tetra(methylphosphonic) acid-modified zirconia particles.

The primary objective of work was to characterize, optimize and model a chromatographic process based on ethylenediamine-N,N,N',N'-tetra(methylphosphonic) acid (EDTPA)-modified zirconia particles. Zirconia particles were produced by spray-drying colloidal zirconia. Zirconia spheres produced were further classified, calcined and modified with EDTPA to yield a solid-phase support for use in bio-c...

On $n$-ary Hypergroups and Fuzzy $n$-ary Homomorphism

Adsorption of Anionic Dyes on Poly(N-vinylpyrrolidone) Modified Bentonite

A composite based on poly(N-vinylpyrrolidone) (PVP) and sodium bentonite was prepared by a simple method. Structural characterizations of the bentonite and the composite were performed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The TGA analysis showed a low loading of the polymer in the bentonite. XRD analysis confirmed a mod...

Structure of the rotor ring modified with N,N'-dicyclohexylcarbodiimide of the Na+-transporting vacuolar ATPase.

The prokaryotic V-ATPase of Enterococcus hirae, closely related to the eukaryotic enzymes, provides a unique opportunity to study the ion-translocation mechanism because it transports Na(+), which can be detected by radioisotope (22Na(+)) experiments and X-ray crystallography. In this study, we demonstrated that the binding affinity of the rotor ring (K ring) for 22Na(+) decreased approximately...