Influence of Magnetic Field in the Kinetics of Crystallization of Diamagnetic and Paramagnetic Inorganic Salts

Abstract

The influence of the magnetic field on some kinetic crystallization parameters of the systems zinc sulfate -water and copper sulfate -water were investigated in a series of controlled batch cooling experiments. The solutions were exposed to magnetic fields with different intensities, up to a maximum of 0.7T. A clear influence of magnetic field on the zinc sulfate crystallization parameters was found: an increase in the saturation temperature, a decrease in the metastable zone width, and increased growth rate and average crystal size. These effects were observed for the diamagnetic zinc sulfate, but not in similar experiments with paramagnetic copper sulfate.

Influence of magnetic field on dealloying of Al-25Ag alloy and formation of nanoporous Ag

“…It is proposed that a magnetic field up to 0.5 T would promote the formation of diamagnetic products in eqn (4). According to some related researches, 42,43 the precipitation, nucleation and growth of some inorganic salts can be influenced by an external magnetic field. Freitas et al 42 have found the growth rate of diamagnetic zinc sulfate can be increased by a 0.7 T magnetic field while no effect was observed in the paramagnetic copper sulfate.…”

“…According to some related researches, 42,43 the precipitation, nucleation and growth of some inorganic salts can be influenced by an external magnetic field. Freitas et al 42 have found the growth rate of diamagnetic zinc sulfate can be increased by a 0.7 T magnetic field while no effect was observed in the paramagnetic copper sulfate. In addition, the similar phenomena have also been discovered by Madsen and his co-workers.…”

“…As a result, Ag atoms in the lattice of the Ag 2 Al phase dynamically rearrange to form a three-dimensional crystalline random porous structure during the dealloying of the Al-25Ag alloy. According to the research about the precipitation of inorganic salts, 42,43 it is found that an external magnetic field could promote the nucleation of diamagnetic salts. Metallic silver is diamagnetic 69 and the magnetic field may promote the nucleation of silver during the etching of Al from Ag 2 Al and accelerate the dealloying process.…”

“…In addition, it is clarified by a series of investigations that an external magnetic field could influence the nucleation or growth of weakly magnetic inorganic salts. [42][43][44] It has been found by Freitas et al 42 and Madsen et al 43 that the formation of diamagnetic inorganic salts was promoted by the external magnetic field. Generally, the dealloying involves the dissolution of the less noble component, and diffusion and migration of the noble component, 13 and the crystal nucleation is necessary during the dealloying process.…”

Observation of cholesterol nucleation in a magnetic field

“…The growth rate of lysozyme crystals was reduced to 60% at 11 T (Yanagiya et al, 2000). But, the increased growth rate and decrease in the metastable zone width under 0.3 T of diamagnetic material was reported by Freitas et al (1999). The experiments were performed under presence of 0.1 T intensity magnetic field, known to have perceptible effect on diamagnetic materials.…”