Von Welsbach, Auer

Carl Auer von Welsbach (1858-1929) separated praseodymium and neodymium. 

Georges Urbain (1872-1938) and Carl Auer von Welsbach confirmed the existence of the element in 1907. 

Neodymium (Nd, [Xe]4/46.s 2), name and symbol after the Greek words veo< + L upoq (neos + didymos, new twin). Discovered (1885) by Carl F. Auer von Welsbach. 

Lutetium (Lu, [Xe]4/ 145 / 6.v2), name and symbol after the Latin word Lutetia (Paris). Discovered (1907) by Georges Urbain and Carl Auer von Welsbach. Silvery white metal. 

Neodymium - the atomic number is 60 and the chemical symbol is Nd. The name was originally neodidymium and was later shortened to neodymium, which is derived from the Greek neos for new and didymos for twin . It was discovered by the Swedish surgeon and chemist Carl Gustav Mosander in 1841, who called it didymium (or twin) because of its similarity to lanthanium which he had previously discovered two years earlier. In 1885, the Austrian chemist Carl Auer von Welsbach separated didymium into two elements. One of which he called neodymium (or new twin). 

It is obvious that the narrow band thermoluminescence 8, 9) influenced Carl Auer von Welsbach in developing his mantle between 1884 and 1892, but as discussed in the next chapter, the optimized conditions for white gas-light rather involve another t cpe of excited states of cerium(IV). On the other hand, the cathodo-luminescence in narrow bands discovered by William Crookes and carefully studied by Urbain [12) corresponds to internal transitions in the partly filled shell. Thus, the excited state of 4/ europium(III) produces the red emission (important for colour television) in the orthovanadate [13) Yi Eux VO 4 and in the oxysulphide (74) by transitions to " Fz, and Fq. Certain... 

Austrian mineralogist Carl Auer von Welsbach Found in the ores bastnasite and in monazite, which contain all of the natural rare earth elements alloy used in the auto and aircraft industries. 

Austrian mineralogist Carl Auer von Welsbach Highly magnetic and used in many commercial applications can be used to detect counterfeit paper money by showing whether the printing ink is magnetic. 

Austrian mineralogist Carl Auer von Welsbach and French scientist Georges Urbain Expensive and rare with few commercial applications name derives from the ancient Roman name for Paris. 

Mosander extracted from the mineral lanthana a rare earth fraction, named didymia in 1841. In 1879, Boisbaudran separated a rare earth oxide called samaria (samarium oxide) from the didymia fraction obtained from the mineral samarskite. Soon after that in 1885, Baron Auer von Welsbach isolated two other rare earths from didymia. He named them as praseodymia (green twin) and neodymia (new twin) after their source didymia (twin). The name praseodymium finally was assigned to this new element, derived from the two Greek words, prasios meaning green and didymos meaning twin. 

The carbon filament lamp vAiich was developed in parallel at the beginning of this century was always several times as expensive in use as an Auer incandescent mantle. As a result, this first use of the rare eaurth elements achieved great economic success and thanks to his capabilities Auer von Welsbach played a major role in this worldwide achievement. He was in the position to survive the extraordinarily corplicated and obstinately pursued patent battles. 

Again, we take a short look into the origin of this discovery, Auer von Welsbach had accumulated so much thorium in the processing of rare earths for production of lanthanumr-zirconium incandescent mantles - the predecessor of Auer incandescent mantles - that he had to look for a use for them. 

Auer von Welsbach was bom in Vienna in 1858. His father was a creative inventor and expert in the field of printing. 

Early in his life he left his children such a large inheritance that his son Karl was able to pursue his studies of chemistry in 1878 in Vienna with Professor lAjeSaen and in 1880 with Bunsen in Heidelberg without material worries. In the laboratory of Bunsen he was first introduced into the chemistry of the rare earth elements. Uhtil his death in 1929 he remained true to this field of work. The intensive involvement in spectroscopy with Bunsen also made him familiar with the problems of radiant li t v ch without doiibt was important for his later invention of Auer-Li t and with that the use of the rare earth elements. Further, he had an insight into the work of winning the rare earth metals from their salts through Bunsen, Hill rand and Norton A)o succeeded for the first time in 1875 to produce rare ecu h metals by electrolysis vhich later was further developed in Munich by Muthmann. Ihe concepts "pyrophor" and "pyrophoricity" originate from Auer von Welsbach. 

Sedlack, Franz "Auer von Welsbach", Blotter fiir Ge-sohichte der Technik, zweites Heft Julius Springer Wien, 1934... 

Origins. Since the 1890 S, monazite, the first commercial rare earth ore, was mined from black beach sands in Brazil and shipped to Austria for its 5 to 10% thorium oxide content. Carl Freiherr Auer von Welsbach spent 20 years of research work developing a bright incandescent gas mantle he discovered in 1866 with... 

Berzelius then mentioned a number of accepted organic names which sound much worse than Didym (10). Didymia was regarded as a pure earth until 1885, when Auer von Welsbach decomposed it. 

Marignac, Lecoq de Boisbaudran, Cleve, and Bohuslav Brauner all believed didymium to be a mixture of elements, but none of them were able to make the difficult separation (49). In 1882 Professor Brauner of the University of Prague examined some of his didymia fractions with the spectroscope and found a group of absorption bands in the blue region (A=449-443) and another in the yellow (A.=590-568) (53, 66)." These two groups of bands are now known to belong to two earths, praseodymia and neodymia, respectively, which Baron Auer von Welsbach obtained in 1885 by splitting didymia (3, 30, 32, 58). 

Baron Auer von Welsbach, 1858-1929. Austrian chemist and chemical technologist. Discoverer of praseodymium and neodymium. Inventor of the Welsbach gas mantle, the osmium filament electric lamp, and the automatic gas lighter. 

Auer von Welsbach also invented tire automatic gas lighter based on a pyrophoric alloy of iron and cerium, and the osmium-filament electric... 

The following literal translation of a postcard from Professor Bohuslav Brauner to Dr. Max Speter is published by kind permission of Dr. Speter. It was written in reply to a question as to whether or not Brauner and Auer von Welsbach were students under Mendeleev. Dr. Brauner was about seventy-eight years old when he wrote this card. 

Marignac, in the future, the credit of his fundamental discovery (52). The other oxide he called lutecia from an old name for his native city, Paris (3, 38, 39, 51). The spelling has been changed to lutetia. The element he named neoytterbium is now known simply as ytterbium. Although these elements were found to be identical with the alde-baranium and cassiopeium discovered independently by Auer von Welsbach at about die same time, Urbains names for them have been widely accepted. ... 

Auer von Welsbach, Carl, "History of the invention of incandescent gas-... 

Aug. 29, 1931). Reprints and reviews of papers by Vauquelin, Mosander, Boisbaudran, Auer von Welsbach, Demarcay, and Harris, Yntema, and Hopkins. 

Sedlacek, F., Auer von Welsbach, Julius Springer, Vienna, 1934, 85 pp. 

Auer von Welsbach announces his separation of didymia into praseodymia and neodymia. 

Death of Auer von Welsbach at Welsbach Castle in Carinthia. 

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