To write the obituary of a personality of exceptional quality is always difficult, and even more so in the case of a man who was a teacher admired by us all and also an irreplaceable friend. Yet nothing else remains than to express the sincerest respect and deep sorrow of the professional community in announcing the death, on 25 December 2014 at the age of not quite 84 years, of one of the most significant nuclear chemists and radioanalysts of recent decades, Prof Dr h.c. Juraj Tölgyessy, Dr Sc., who was a member of the European Academy of Sciences and Arts. A sufficiently concise obituary cannot be written about a man with Professor Tölgyessy’s stature, so I apologise for it being incomplete and not perfect.

Juraj Tölgyessy was born in Dunajská Streda on 27 January 1931, the son of a music teacher. He studied as an undergraduate with the Faculty of Chemistry at Slovak Technical University in Bratislava, graduating in 1953 with honours, and in 1959 defended his dissertation on “Radiometric Titration” before the Faculty of Inorganic Technology at the Institute of Chemical Technology in Prague. In 1968, as a 37-year old scientist, he defended his doctoral dissertation on “Volumetric analysis using radiometric indication of the equivalence point” at the Faculty of Chemistry in Lomonosov Moscow State University. In the same year he co-founded and was editor of the Journal of Radioanalytical and Nuclear Chemistry, which at the time was published in two parts: Radiochemical and Radioanalytical Letters and Journal of Radioanalytical Chemistry. Starting in 1968, he was an expert at the International Atomic Energy Agency, spending several years lecturing and conducting research in many countries around the world such as Mongolia, Cuba, Albania, Mexico, Cyprus and Myanmar. In 1969 he became an associate professor at the Department of Radiochemistry and Radiation Chemistry with the Faculty of Chemical Technology at Slovak Technical University in Bratislava before being appointed full professor of nuclear chemistry in 1973. At the same faculty in 1978, he established the Department of Environmental Chemistry and Technology, which he headed for more than 15 years. In 2000 he was invited to Matej Bel University, where he would spend over 11 years and, in the course of his research, lecturing and organizational activities, founded the Department of Environment Ecology. Until the end of his life he served on scientific committees and as a discussant for doctoral and professorial dissertations, while staying in intensive professional and friendly contact with his former students, colleagues and young scientists both locally and internationally.

It would not be possible in a brief obituary of such an extremely prolific man as Professor Tölgyessy to summarise the important work he did, whose output and significance, especially in radioanalytical chemistry, exceeds values anyone would normally expect. He wrote 98 books and monographs as well as 60 university textbooks, held 22 patents and published hundreds of original scientific papers. Of the dozens of awards and honours he received, the one he most treasured was the George Hevesy Medal, which is well-known as the premier international award of excellence in radioanalytical and nuclear chemistry. Professor Tölgyessy received this medal together with Professor Tibor Braun in 1975.

Such an honourable professor, dear teacher and friend will be incredibly missed, especially his exceptional scientific inventiveness, constructive criticism and unselfish friendship as well as his witty humour, endless optimism and inimitable industriousness, and above all his warm and kind heart.

In Memory of Our Departed Colleague,

Dr. habil. Juraj Lesný, PhD.