Heavy metals as markers for assessing environmental pollution from chemical warehouse and plastics fires

Case histories of large, accidental fires are presented to illustrate that heavy metals may be used as markers to assess the extent of localized environmental contamination resulting from fires. Due to the complexity of fire chemistry with respect to organic pollutants, determination of organic pollutants in the environment following a fire would be time consuming and expensive. Using heavy metals as markers on the other hand is much cheaper and can be done very rapidly. © 1995.

A review of high magnetic moment thin films for microscale and nanotechnology applications

The creation of large magnetic fields is a necessary component in many technologies, ranging from magnetic resonance imaging, electric motors and generators, and magnetic hard disk drives in information storage. This is typically done by inserting a ferromagnetic pole piece with a large magnetisation density MS in a solenoid. In addition to large MS, it is usually required or desired that the ferromagnet is magnetically soft and has a Curie temperature well above the operating temperature of the device. A variety of ferromagnetic materials are currently in use, ranging from FeCo alloys in, for example, hard disk drives, to rare earth metals operating at cryogenic temperatures in superconducting solenoids. These latter can exceed the limit on MS for transition metal alloys given by the Slater-Pauling curve. This article reviews different materials and concepts in use or proposed for technological applications that require a large MS, with an emphasis on nanoscale material systems, such as thin and ultra-thin films. Attention is also paid to other requirements or properties, such as the Curie temperature and magnetic softness. In a final summary, we evaluate the actual applicability of the discussed materials for use as pole tips in electromagnets, in particular, in nanoscale magnetic hard disk drive read-write heads; the technological advancement of the latter has been a very strong driving force in the development of the field of nanomagnetism.