Magnetic particles dispersion

Another class of solvents that appears to have significant appeal for green processing of metal waste solutions relies on solvent-coated magnetic particles dispersed within the feed phase to be treated (Nunez et al., 1996). Once the desired solutes have been removed by extraction, these particles can be recovered conveniently using magnetic filtration. 

Inoue, H., Fukke, H., and Katsumoto, H., Effect of polymer adsorbed layer on magnetic particle dispersion, IEEE Trans. Magn., 26, 75, 1990. 

The new generation of magnetic elastomers and gels represent a new type of composites, consisting of small (mainly nano- and micron-sized) magnetic particles dispersed in a high elastic polymeric matrix [11-51]. These materi-... 

If the magnetoelast contains magnetic particles dispersed randomly, there are two basic experimental situations The compressive force (Fx) and the direction of magnetic field (characterized by the magnetic induction, B) can be either parallel or perpendicular, as shown on Fig. 20. In one of our previous papers, we found a 20% increase of the modulus for a magnetoelast containing randomly distributed magnetic particles [37]. 

The method is affected by different parameters like the type and concentration of salts, temperature, pH and the addition rate of ammonia. After coprecipitation by the addition of a basic medium, the system is subjected to different purification steps like magnetic separation, filtration and washing. It should be mentioned here that a rapid pH increase (from 8.5 to 10), and not using strong bases like LiOH or NaOH, are important to avoid the precipitation of nonmagnetic hydroxides of iron [71]. Nanosized iron oxide magnetic particles dispersed in aqueous or organic medium can be directly produced by this wet chemical method. 

Magnetic particle dispersant for recording tape Canada 1,043,638 1978 Fuji Photo Film... 

The energies can be attractive or repulsive generally, the electrostatic repulsion energy [12] and Van der Waals attraction energy (F ) [13] act between non magnetic particles dispersed in aqueous carriers. 

An MR hydrogel of a crosslinked PVA network and Fe304 particles dispersed at random was also synthesized [59]. The viscosity of the gel in a magnetic field increased with time. It has been suggested that the dispersed Fe304 particles aggregate and form a cluster. The effect of the volume fraction of the particles on the viscosity has also been discussed. The authors have pointed out that when the volume fraction is about 15%, the ratio of the viscosities with and... 

In this connection, attention should be paid to an unusual NMR technique called nuclear magnetic relaxation dispersion (NMRD). In contrast with NMR spectroscopy, the NMRD signal arises from the nuclei of the abundant solvent molecules and not from the dissolved substances. The relaxation properties of the solvent molecules are profoundly modified if the solvent contains paramagnetic particles (see a review by Desreux 2005). A solvent molecule sails in the vicinity of an ion-radical and finds itself in the local magnetic field of this paramagnetic particle. Then, induced magnetism of the solvent molecule dissipates in the solvent bulk. This kind of relaxation seems to be registered by NMR. NMRD is applicable to studies on ion-radical solvation/desolvation, ion-pair dynamics, kinetics of ion-radical accumulation/consumption, and so on. 

The stability of iron oxide suspensions is relevant to fields as varied as the paint industry, extraction of iron from its ores, the structure of soils, hydrometallurgy and waste water treatment. The ease of homogensisation of paint, for example, is controlled by proper adjustment of the stability of the pigment suspensions. In ground waters, the settling behaviour of small iron oxide particles influences transportation of trace elements and radio-nuclides. The stability of a dispersion of magnetic particles can determine the quality of ferrofluids and magnetic tapes. 

Coercive Force and Dispersibility of Magnetic Particles for Recording Media... 

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