Electro-magnetic separation

Electro-magnetic separation is the only method by which the isotopes of an element can be completely separated from one another. The separation is carried out by the mass spectrograph which works on the principle elaborated earlier for the mass spectrometer (Chapter 13). Working of the Dempster s mass spectrograph diagramatically represented by Figure 19.4, illustrates the basics of electromagnetic separation of isotopes. 

Several processes are used to enhance the filtration process itself. They may also be related processes in their own right. They include washing of solids, cake dewatering, pretreatment of suspensions (addition of inert filler aids), mechanical squeezing of cakes, electro-kinetic effects (Table 1). and magnetic separation. 

The great English scientist saw in these positive rays a possible vindication of Soddy s isotopes with which he had just ruffled the chemical world He argued that if these ions came from atoms of the same element having different atomic weights, then some means could be found to separate the element into its various isotopes. A powerful electro-magnetic field could sort them out very neatly since the lighter ions would be deflected most. 

Fig. 11.4 Schemes demonstrating two SERS mechanisms, (a) Local field concentration near the gap between two particles [19]. The white spheres and polygons are silver, and the color scale bar indicates the electro-magnetic field enhancement. The separation distance is 1 and 5.5 nm for the first and second columns, respectively. The wavelength of the incident field is 514.5 nm with vertical polarization, and (b) Possible charge transfer excitations between molecule and metal [22]. The occupied and unoccupied molecular orbitals are broadened by the molecule-metal interactions. Metal-to-molecule and molecule-to-metal charge transfers are indicated by arrows...

The common instruments use electron-impact ionisation, an ion separation by a (permanent or an electro-) magnet, high voltage ion acceleration and a double or triple Faraday cup set for ion current measurement. The ion current for the compound with the lower abundance isotopologue is amplified 100 to 1000 times in correspondence to that for the main isotopologue. For more details about the technical side of mass spectrometers and the measuring procedures, see e.g. references [134, 135],... 

In the future, the practise of separation of municipal waste before incineration will be more popular. Then, Ni-Cd batteries could be easily removed from municipal waste streams by using an electro-magnet overband in order to remove all Ni-Cd batteries together with other ferro-magnetic materials. This technology is currently used in the Netherlands (CollectNiCad 2001). 

Metal detection by diverse electro-magnetic methods, viz. Eddy current for A1 separation, magnetic field for removal of Fe, etc. 

Column heads of semi-technical plants are made up of separate condenser and reflux units. The valves are operated mechanically and, more commonly, electro-magnetically. Their operation is similar to that in laboratory column heads (Figs. 306, 247). The valves are controlled automatically by means of electromagnets, electromotors or pneumatic drives (Fig. 248). For the automatic division of liquid, however, the swinging funnel is chiefly used (Fig. 142) which is actuated by an electromagnet placed outside the column wall. With the magnet switched on the distillate is taken off laterally. 

Magnetic and electro- Separation of ferrous and nonferrous Magnetic separation for ferrous materials eddy-current separation... 

During initial periods, there were large number of spurious scram due to electro magnetic noise pickup by start up and delayed neutron detector channels and due to cross talk of fine impure test (FIT) pulse. Remedial measures viz., separation of signal cables from power cables, improvements in grounding system and reshaping FIT pulse were carried out and system performance improved. 

The Ramsey principle for the interaction of an atom moving in time through different electro-magnetic fields can be also realized in a completely different way. Atoms in a collimated beam are irradiated with an equidistant pulse train from a laser beam travelling collinearly with the atomic beam (Fig. 9.64). The distance Af between successive pulses corresponds to the flight time of molecules between the separated fields in the classical Ramsey method. 

On the other hand it is helieved, that a CCF potential of sohd-state components is extremely low from the hardware point of view in the case that all common recpiirements for environment (Electro Magnetic Compatihdity, humidity, air condition, separation etc.) are fidfilled. The software as a main potential source of CCF is then focused on. 

PWay -Traction Power Supply CH06. Electro-Magnetic Interference (EMI) caused to by railway operations CH13. Inappropriate separation between uninsulated live conductors people. 

Separate raceway systems (e.g., conduits, cable trays, ducts, and wire-ways) are not required because electro-magnetic compatibility (EMC) issues are addressed consistent with good engineering practices for ... 

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