HISTORY · PEOPLE · APPLICATIONS
The questions, collaborations and contributions behind our understanding of the elements.
Born 1948
Yoshino joined Asahi Kasei in 1972 after studying at Kyoto University. His development program explored rechargeable cells using lithium cobalt oxide and carbon-based negative electrodes. In 1985 a petroleum-coke host helped establish a commercially viable lithium-ion architecture. The work involved materials selection, prototypes, patents, and practical evaluation, as well as the electrochemical principle of storing lithium ions in host materials.
1915–2010
Ghiorso came to the Berkeley laboratory as an electronics builder rather than as a physicist or chemist, and the detectors and data systems he designed are what made single-atom identification workable. He co-discovered more elements than anyone else, largely because the identification of a few atoms depends on distinguishing a genuine decay chain from background — a problem of instrumentation and analysis as much as of nuclear reactions. He also designed the HILAC and its successor, the accelerators that produced most of the Berkeley elements.
1767–1813
Ekeberg taught at Uppsala and was among the Swedish chemists who introduced Lavoisier’s nomenclature into Swedish practice. He worked on the minerals of Ytterby and the surrounding region, which were then yielding more new substances than any other locality in Europe. Deafness from a childhood illness and the loss of an eye in a laboratory accident did not interrupt a career spent almost entirely at the analytical bench.
1743–1794
Lavoisier helped reorganize chemistry around the composition of substances and measurements of mass. He interpreted combustion as combination with oxygen, and his account explained the increased mass of many metals after burning. His laboratory and publications depended on collaborators, including Marie-Anne Paulze Lavoisier. His 1789 textbook consolidated a new chemical language, although parts of the system, including his account of acidity, were later corrected.
1777–1838
Courtois inherited a saltpetre works and spent his career in the practical chemistry of nitrate production, which in Napoleonic France meant processing large quantities of seaweed ash for the potassium salts it contained. That industrial context is what put him in contact with concentrated marine residues; the discovery attributed to him is a manufacturing accident noticed by someone who knew what ought to have happened. He gained little financially from it and died in poverty.
1858–1929
Auer von Welsbach trained under Bunsen in Heidelberg, where spectroscopic evidence was part of the ordinary equipment of chemistry, and returned to Austria to combine rare-earth separation with manufacture. He is one of the few figures in this history who both did the fractional crystallization himself and built industries on the products. His laboratory notebooks record separations carried through thousands of cycles; his commercial work turned two of the resulting oxides into a lighting product and a mixed rare-earth alloy into a spark-producing flint.
1797–1858
Mosander worked in Stockholm in Berzelius’s circle, first in pharmacy and medicine and then in mineral analysis, and he inherited the problem that the Swedish minerals cerite and gadolinite had handed to the previous generation. His method was fractional treatment carried out with unusual persistence: dissolve, precipitate part of the material under carefully chosen conditions, set the fractions aside, and repeat until the properties of successive fractions stopped drifting. That drift was the evidence. A single earth that behaved slightly differently after each cycle was, to him, a mixture that had not yet been taken apart.
1742–1786
Scheele was a German-Swedish pharmaceutical chemist whose investigations included oxygen, chlorine, and manganese compounds. He prepared oxygen independently before Priestley, but his book on air and fire was published in 1777. His experiments were often expressed in the language of phlogiston. Reading that language carefully preserves the distinction between an observed reaction and a later explanation of it.
1900–1979
Payne-Gaposchkin brought physics and astronomy together to interpret stellar spectra. At Harvard, her 1925 dissertation inferred the dominance of hydrogen and helium by accounting for how physical conditions affect atomic absorption. Her analysis used Saha’s ionization equations and drew on an established observational archive. She later studied variable stars and their relationship to galactic structure. Her research extended well beyond the famous thesis.
1838–1904
Winkler grew up around smelting works and taught at the Freiberg Mining Academy, and his instincts were those of an industrial analyst: when an analysis does not add up, the missing fraction is a fact about the sample, not a nuisance. He also worked on the contact process for sulfuric acid and on gas analysis, and wrote extensively on analytical technique.
born 1926
Hoffman worked at Los Alamos and then at Berkeley on the chemistry and spontaneous fission of the heaviest elements, and her group did much of the work showing that one-atom chemistry is possible at all: an atom’s behavior can be read from where it deposits in a temperature-gradient column or how it partitions between phases, provided the experiment is repeated enough times to be statistically meaningful. She also showed that plutonium-244 occurs in nature, in a Precambrian mineral.
1834–1907
Mendeleev developed the periodic law while writing a chemistry textbook. His 1869 system organized the known elements and turned irregularities into questions about missing elements or uncertain atomic weights. He later worked on standards of weights and measures and advised on industrial matters. His career connected teaching, experimental chemistry, classification, and public institutions; the table was one part of that broader activity.
