The effect of interactions of various Ia and IIa cations with two positions of the adenine-thymine (A−T) and guanine-cytosine (G−C) base pairs on the geometries and individual hydrogen bond (HB) energies have been investigated by using the atoms in molecules (AIM) method at the B3LYP/6-311++G(d,p) level of theory. The cations that possess higher charge/radius (q/rad) ratio make higher changes o...

The aim of this study was to develop an extended-release tablet formulation using a new in situ cross-linking method. The effects of polyvalent cations on theophylline release from tablets made with the polyanionic polymers sodium alginate and sodium carboxymethylcellulose, were investigated. Different miliequivalents of the di and tri-valent cation, Ca2+ and Al3+, were added to tablet form...

The aim of this study was to develop an extended-release tablet formulation using a new in situ cross-linking method. The effects of polyvalent cations on theophylline release from tablets made with the polyanionic polymers sodium alginate and sodium carboxymethylcellulose, were investigated. Different miliequivalents of the di and tri-valent cation, Ca2+ and Al3+, were added to tablet form...

The expressiveness of the declarative language G odel can be improved by adding to it bounded quanti cations, i.e., quanti cations over nite domains, and arrays. Many problems can be expressed more concisely using bounded quanti cations than using recursion. Arrays are natural for many applications, e.g., in scienti c computing, and are conveniently used in bounded quanti cations. Treating bou...

Calix[8]arenes of conformational rigid were isolated. The NMR parameters of the structure of calix[8]arenes have been compared. The study of organic structures to form nanoporous materials is well-known in chemistry phenomena to find the crystal form of calix[8]arene as supramolecule. Investigated and compared hydrogen bonding, oxygen and nitrogen atoms effect on calix[8]arene and its complexes...