ABSTRACT
Magnetic magnetite (Fe3O4) nanoparticles with average sizes of 5.11, 10.53, and 14.76 nm were synthesized by the chemical co-precipitation method. The surface area of Fe3O4 nanoparticles (average size of 5.11 nm) had the largest value of 167 m²/g. The adsorption capacity for removing arsenic (As(V)) from water at 3 ppm concentration was investigated by atomic absorption spectroscopy. Results showed that the As(V) adsorption capacity of Fe3O4 was dependent on particle size. The maximum absorption efficiency (Hmax) reached 99.02%, the equilibrium time was 30 min; the maximum Langmuir isotherm adsorption capacity was 14.46 mg/g with Fe3O4 nanoparticle an average size of 5 nm. The results indicate that reducing the size of Fe3O4 nanoparticles is a promised way for As(V) ion removal from water and wastewater treatment.
ABSTRACT
A phylogenetic analysis of VP1 and VP4 nucleotide sequences of 52 recent CVA16 strains demonstrated two distinct CVA16 genogroups, A and B, with the prototype strain being the only member of genogroup A. CVA16 G-10, the prototype strain, showed a nucleotide difference of 27.7-30.2% and 19.9-25.2% in VP1 and VP4, respectively, in relation to other CVA16 strains, which formed two separate lineages in genogroup B with nucleotide variation of less than 13.4% and less than 16.3% in VP1 and VP4, respectively. Lineage 1 strains circulating before 2000 were later displaced by lineage 2 strains.