Alexander Friedrich Just (12 April 1874, in

Bremen Bremen (Low German also: ''Breem'' or ''Bräm''), officially the City Municipality of Bremen (german: Stadtgemeinde Bremen, ), is the capital of the German state Free Hanseatic City of Bremen (''Freie Hansestadt Bremen''), a two-city-state consis ...

– 30 May 1937, in

Budapest Budapest (, ; ) is the capital and most populous city of Hungary. It is the ninth-largest city in the European Union by population within city limits and the second-largest city on the Danube river; the city has an estimated population ...

) was an

Austro-Hungarian Austria-Hungary, often referred to as the Austro-Hungarian Empire,, the Dual Monarchy, or Austria, was a constitutional monarchy and great power in Central Europe between 1867 and 1918. It was formed with the Austro-Hungarian Compromise of ...

chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe th ...

and inventor. Later, in Hungary he used the name Just Sándor Frigyes. In 1904 with Austro-Hungarian

Franjo Hanaman Franjo Hanaman (June 30, 1878 – January 23, 1941) was a Croatian inventor, engineer, and chemist, who gained world recognition for inventing the world's first applied electric light-bulb with a metal filament (tungsten) with his assistant Alex ...

he was the first to develop and patent an

incandescent light bulb An incandescent light bulb, incandescent lamp or incandescent light globe is an electric light with a wire filament heated until it glows. The filament is enclosed in a glass bulb with a vacuum or inert gas to protect the filament from oxida ...

with a

tungsten Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolat ...

filament, made by extruding a paste of tungsten powder and a carbonaceous binder to produce a fine thread, then removing the carbon by heating in an atmosphere of hydrogen and water vapors. Just and Hanaman received a Hungarian patent in 1904, and later US Patent 1,018,502. In 1905, Just and Hanaman patented a process for producing tungsten filaments by plating carbon filaments with tungsten, then removing the carbon by heating. These early tungsten lamps were more efficient than a carbon filament lamp, because they could operate at a high temperature, due to the high melting point of tungsten. The tungsten was, however, so brittle that these lamps were of limited practical use.Day, Lance and McNeil, Ian "Biographical dictionary of the history of technology," Routledge, 1996. Cited edition is Taylor & Francis eBook, 2005, page 290. . Retrieved December 14, 2011. It was supplanted by the drawn tungsten filament lamp, developed in 1910 by

William David Coolidge William David Coolidge (; October 23, 1873 – February 3, 1975) was an American physicist and engineer, who made major contributions to X-ray machines. He was the director of the General Electric Research Laboratory and a vice-president of t ...

References

External links

NY-Times 16 April 1916 about Just
(pdf) * {{DEFAULTSORT:Just, Alexander 1874 births 1937 deaths Austro-Hungarian inventors 20th-century German chemists Hungarian chemists Scientists from Budapest Scientists from Bremen