Permanent magnet applications

Gadolinium (Gd) can also be magnetized permanently at temperatures < 16 °C, but the number of industrial applications is slight. 

Hard magnetic materials have rather rectangular, broad, hysteresis curves (Figure 12.16). These materials are used in permanent magnets, with applications from door catches to electric motors. The hexagonal ferrites are hard magnetic materials, as are alloys such as SmCos and Nd2Fei4B. 

The most spectacular applications of ECLs are the possibiUty of direct overwrite (DOW) with laser modulation (79,80) and of magnetically iaduced superresolution (81,82). The stacks comprise at least a storage layer s and a bias layer b. For both appHcations, the storage layer s has the lower and the higher at room temperature when compared to the bias layer b. At room temperature, b is homogeneously magnetized (initialized) by an external permanent magnet is about 400 kA/m (5 kOe)). 

Cathodic protection apparatuses are well proven, widely used devices and are not to be confused with magnetic devices gadgets ) or other similar but generally less than satisfactory items of capital equipment. Cathodic protection devices reverse the tendency of a metal to go into solution at the anode (corrosion) by the application of a counter-potential. This counter-potential or electromotive force (EMF) is provided either from a permanent external source such as a battery or rectifier or from the installation of a sacrificial anode. 

The intention of this work was not to consider whether the specific experimental system used here would be applicable to an actual industrial setting. Rather, the work has set the stage to move beyond the question of whether the technique can be applied, but when. The barriers to its implementation are two-fold. Firstly, the specific technology must be developed for a particular process line. Secondly, the cost of the MRI is prohibitive, although with the use of electromagnets and permanent magnets for MRI, this is becoming less of a factor. Furthermore, when compared with other on-line instruments that promise far less in terms of... 

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