Nano-structure formation and function control of colloidal materials due to strong magnetic fields

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Colloid-dimensional assemblies comprising weak magnetic systems, such as hydrogels, lipid vesicles, coacervates, triblockpolymer/silicate hybrids, mesoporous silicas, and organometal complex, were organized and functionalized by magnetic fields. Potential ability of magnetic fields were investigated from the viewpoint of magnetically responsive structures in porous solids and biological materials.Self-organization of various structures due to magnetic fields and magnetic-field sensitization of functions due to additives with magnetic anisotropy were examined. This preliminary success led to a new, simple method to control anisotropic nono-textures and nano-structures based on their magnetism. For examples, two kinds of new cupper-pyrazine complexes were prepared from the same reactants solution and conditions, besides using magnetic fields. This results in magnetic anisotropy originated from crystal structure. Moreover, concentration fluctuation in liquid-liquid mixtures was controlled … More under magnetic force fields produced by magnetic field gradient, and detected by dynamic and static light scattering. Metal structure formation associated with non-linear chemical reaction was examined under magnetic fields. Volume phase transition gels and vesicles were deformed by external magnetic fields and the magnetic deformation was enhanced by the addition of magneitically anisotropic molecules.The magnetoadsorptivity of H_2 onto various carbons including a single wall carbon nanotube depended markedly on temperature. H_2 vapor was adsorbed much larger than the supercritical gas by magnetic field. In the vapor region, the pressure change Ap depends on T^<-1.4>. On the other hands, in the supercritical region, Δp depends on ( T-Tc)^<-0.09> below 40K and (T-Tc)^<-0.34> in the range 40-303K, suggesting two magnetic states of supercritical states in the micropores. Based on the results, new tunneling reaction systems were constructed using adsorption systems comprising hydrogen and carbons, and the tunneling reactions were controlled by magnetic fields.Whether or not there is so-called magnetized water was examind. Very elaborate investigation showed that pure water was not "magnetized", but the water exposed to oxygen was "magnetized" by magnetic treatment. The degree of "magnetization" of water can be quantitatively and easily evaluated by the contact angle. Less