Mercury, initial discovery

After the initial discovery by Onnes of superconductivity in mercury, tin, and lead, research focused on the discovery of new superconducting phases with even higher values. It was found that 25 % of the elements of the periodic table are superconductors and that a plethora of alloys exhibit superconductivity [16]. A theory to describe the phenomenon of superconductivity was introduced by Bardeen, Cooper, and Schrieffer (BCS) which, as originally formulated, placed an upper limit on Tc of about 35 to 40 K [19]. For a synopsis of the historical development of superconductor theory, see [20]. We shall use the term low temperature superconductor (LTS) as a reference to those materials which possess values less than the theoretical limit of 35 to 40 K imposed by the original BCS theory. 

The discovery of mercury fulminate [Hg(CNO)2] by Alfred Nobel in 1864 improved the initiation process. This chemical complex replaced the black powder in the initiation of nitroglycerine in boreholes. 

More recently, there has been the discovery that maity natural and synthetic compounds mimic the actions of hormones and can disrupt reproductive patterns. The most widely noted phenomenon is the feminization of male fish, but certainly the problem extends throughout the food chain. Initially, most endocrine disrapters were believed to be compounds with some stractural similarity to natural hormones. More recent work has indicated that a wide range of materials, including heavy metals such as arsenic and mercury, may be involved. 

Since the discovery of PTFE a considerable research efforts focused on the photo-initiated polymerization of TFE. Polymer has been produced in the mercury-sensitized photolysis of gaseous TFE. However, analysis showed perfluorocyclopropane to be the main product. At pressures less than 8 kPa it is reported to be the only product [695,696]. Photopolymerization of gaseous TFE has also been reported in the presence of mercury bromide, phosgene, and nitrous oxide [697 99]. Atkinson [697] has observed that mercury bromide activated by light of 365 nm initiates the photochemical polymerization of TFE. 

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