Hulm, John

Hulme M. Barrow E.M. Arnell N.W. Harrison P.A. Johns T.C. and Downing T.E. (1999). Relative impacts of human-induced climate change and climate variability. Nature, 397, 689-691. 

Niobium, discovered in 1801 and formerly called colum-bium, was a special favorite. A soft, ductile, gray-blue metal, it is present in several minerals, forms a number of compounds and complexes, and is used to strengthen welded joints and certain steels. In 1941, scientists reported superconductivity in niobium nitride with a Tc around 16° K, fairly high compared to earlier superconductors. Progress slowed after that until 1953, when John Hulm, of the University of Chicago, put together a material... 

The magnets do require expensive helium refrigeration systems to cool the niobium-titanium coils to superconducting temperatures. Thus, a liquid nitrogen system should be less expensive, simpler to operate, and more reliable. But some scientists are dubious. Said John Hulm ... 

Hulme M, Barrow EB, Amell NW, Harrison PA, Johns TC, Downing TE (1999) Nature... 

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