Zeolites A, X and HS were synthesized from natural Iranian Kaolinite by alkaline fusion,,followed by refluxing the mixture. The transformation of zeolites X to HS and Y to P were studied at different time intervals by X-ray diffraction and Scanning Electron Microscopy (SEM). It was revealed that in solution, zeolites HS and P are more stable than zeolites X and Y respectively

Horizontal gene transfer allows rapid spread of antibiotic resistance genes1, which in bacteria inhabiting natural aquatic systems occurs by conjugation, transduction, and transformation2. Natural genetic transformation is characterized by the uptake of free DNA by a recipient bacterium, its chromosomal integration or extrachromosomal stabilization, and its expression, which leads to a new phen...