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1 Crookes, Sir William
SUBJECT AREA: Electricity[br]b. 17 June 1832 London, Englandd. 4 April 1919 London, England[br]English chemist and physicist who carried out studies of electrical discharges and cathode rays in rarefied gases, leading to the development of the cathode ray tube; discoverer of the element thallium and the principle of the Crookes radiometer.[br]Crookes entered the Royal College of Chemistry at the age of 15, and from 1850 to 1854 held the appointment of Assistant at the college. In 1854 he became Superintendent of the Meteorological Department at the Radcliffe Observatory in Oxford. He moved to a post at the College of Science in Chester the following year. Soon after this he inherited a large fortune and set up his own private laboratory in London. There he studied the nature of electrical discharges in gases at low pressure and discovered the dark space (later named after him) that surrounds the negative electrode, or cathode. He also established that the rays produced in the process (subsequently shown by J.J.Thompson to be a stream of electrons) not only travelled in straight lines, but were also capable of producing heat and/or light upon impact with suitable anode materials. Using a variety of new methods to investigate these "cathode" rays, he applied them to the spectral analysis of compounds of selenium and, as a result, in 1861 he discovered the element thallium, finally establishing its atomic weight in 1873. Following his discovery of thallium, he became involved in two main lines of research: the properties of rarified gases, and the investigation of the elements of the "rare earths". It was also during these experiments that he discovered the principle of the Crookes radiometer, a device in which light is converted into rotational motion and which used to be found frequently in the shop windows of English opticians. Also among the fruits of this work were the Crookes tubes and the development of spectacle lenses with differential ranges of radiational absorption. In the 1870s he became interested in spiritualism and acquired a reputation for his studies of psychic phenomena, but at the turn of the century he returned to traditional scientific investigations. In 1892 he wrote about the possibility of wireless telegraphy. His work in the field of radioactivity led to the invention of the spinthariscope, an early type of detector of alpha particles. In 1900 he undertook investigations into uranium which led to the study of scintillation, an important tool in the study of radioactivity.While the theoretical basis of his work has not stood the test of time, his material discoveries, observations and investigations of new facts formed a basis on which others such as J.J. Thomson were to develop subatomic theory. His later involvement in the investigation of spiritualism led to much criticism, but could be justified on the basis of a belief in the duty to investigate all phenomena.[br]Principal Honours and DistinctionsKnighted 1897. Order of Merit 1910. FRS 1863. President, Royal Society 1913–15. Honorary LLD Birmingham. Honorary DSc Oxon, Cambridge, Sheffield, Durham, Ireland and Cape of Good Hope.Bibliography1874, On Attraction and Repulsion Resulting from Radiation.1874, "Researches in the phenomenon of spiritualism", Society of Metaphysics; reprinted in facsimile, 1986.For many years he was also Proprietor and Editor of Chemical News.Further ReadingE.E.Fournier D'Albe, 1923, Life of Sir William Crookes. Who Was Who II, 1916–28, London: A. \& C. Black. T.I.Williams, 1969, A Biographical Dictionary of Scientists. See also Braun, Karl Ferdinand.KF / MG -
2 William Crookes
m.William Crookes, Sir William Crookes. -
3 Crookes
m.Crookes, Sir William Crookes. -
4 Electricity
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5 Haber, Fritz
SUBJECT AREA: Chemical technology[br]b. 9 December 1868 Breslau, Germany (now Wroclaw, Poland)d. 29 January 1934 Basel, Switzerland[br]German chemist, inventor of the process for the synthesis of ammonia.[br]Haber's father was a manufacturer of dyestuffs, so he studied organic chemistry at Berlin and Heidelberg universities to equip him to enter his father's firm. But his interest turned to physical chemistry and remained there throughout his life. He became Assistant at the Technische Hochschule in Karlsruhe in 1894; his first work there was on pyrolysis and electrochemistry, and he published his Grundrisse der technischen Electrochemie in 1898. Haber became famous for thorough and illuminating theoretical studies in areas of growing practical importance. He rose through the academic ranks and was appointed a full professor in 1906. In 1912 he was also appointed Director of the Institute of Physical Chemistry and Electrochemistry at Dahlem, outside Berlin.Early in the twentieth century Haber invented a process for the synthesis of ammonia. The English chemist and physicist Sir William Crookes (1832–1919) had warned of the danger of mass hunger because the deposits of Chilean nitrate were becoming exhausted and nitrogenous fertilizers would not suffice for the world's growing population. A solution lay in the use of the nitrogen in the air, and the efforts of chemists centred on ways of converting it to usable nitrate. Haber was aware of contemporary work on the fixation of nitrogen by the cyanamide and arc processes, but in 1904 he turned to the study of ammonia formation from its elements, nitrogen and hydrogen. During 1907–9 Haber found that the yield of ammonia reached an industrially viable level if the reaction took place under a pressure of 150–200 atmospheres and a temperature of 600°C (1,112° F) in the presence of a suitable catalyst—first osmium, later uranium. He devised an apparatus in which a mixture of the gases was pumped through a converter, in which the ammonia formed was withdrawn while the unchanged gases were recirculated. By 1913, Haber's collaborator, Carl Bosch had succeeded in raising this laboratory process to the industrial scale. It was the first successful high-pressure industrial chemical process, and solved the nitrogen problem. The outbreak of the First World War directed the work of the institute in Dahlem to military purposes, and Haber was placed in charge of chemical warfare. In this capacity, he developed poisonous gases as well as the means of defence against them, such as gas masks. The synthetic-ammonia process was diverted to produce nitric acid for explosives. The great benefits and achievement of the Haber-Bosch process were recognized by the award in 1919 of the Nobel Prize in Chemistry, but on account of Haber's association with chemical warfare, British, French and American scientists denounced the award; this only added to the sense of bitterness he already felt at his country's defeat in the war. He concentrated on the theoretical studies for which he was renowned, in particular on pyrolysis and autoxidation, and both the Karlsruhe and the Dahlem laboratories became international centres for discussion and research in physical chemistry.With the Nazi takeover in 1933, Haber found that, as a Jew, he was relegated to second-class status. He did not see why he should appoint staff on account of their grandmothers instead of their ability, so he resigned his posts and went into exile. For some months he accepted hospitality in Cambridge, but he was on his way to a new post in what is now Israel when he died suddenly in Basel, Switzerland.[br]Bibliography1898, Grundrisse der technischen Electrochemie.1927, Aus Leben und Beruf.Further ReadingJ.E.Coates, 1939, "The Haber Memorial Lecture", Journal of the Chemical Society: 1,642–72.M.Goran, 1967, The Story of Fritz Haber, Norman, OK: University of Oklahoma Press (includes a complete list of Haber's works).LRD
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Crookes,Sir William — Crookes (kro͝oks), Sir William. 1832 1919. British chemist and physicist who discovered thallium (1861), invented the radiometer (1875), and studied cathode rays. * * * … Universalium
Crookes , Sir William — (1832–1919) British chemist and physicist Crookes studied at the Royal College of Chemistry in his native city of London, under August von Hofmann (1848). After working at the Radcliffe Observatory, Oxford, and the Chester College of Science, he… … Scientists
Crookes, Sir William — ▪ British chemist born June 17, 1832, London, Eng. died April 4, 1919, London British chemist and physicist noted for his discovery of the element thallium and for his cathode ray studies, fundamental in the development of atomic physics.… … Universalium
Sir William Crookes — William Crookes William Crookes Sir William Crookes (17 juin 1832 4 avril 1919) est un chimiste et un physicien britannique qui a donné son nom à la technique des tubes dits de Crooks grâce auxquels ont été découverts par exemple les rayons X. Il … Wikipédia en Français
Ramsay , Sir William — (1852–1916) British chemist Ramsay came from a scientific background in Glasgow, his father being an engineer and one of his uncles a professor of geology. He studied at Glasgow University (1866–69) and returned there as an assistant in 1872… … Scientists
Sir William Crookes — noun English chemist and physicist; discovered thallium; invented the radiometer and studied cathode rays (1832 1919) • Syn: ↑Crookes, ↑William Crookes • Instance Hypernyms: ↑chemist, ↑physicist … Useful english dictionary
William Crookes — Sir William Crookes Nacimiento 17 de junio de 1832 Londres, Reino Unido Fallecimiento 4 de … Wikipedia Español
William Crookes — Sir William Crookes (* 17. Juni 1832 in London; † 4. April 1919 ebenda) war ein britischer Physiker, Chemiker, Wissenschaftsjournalist und Parapsychologe. Crookes hat die Kathodenstrahlen sichtbar gemacht, die Grundla … Deutsch Wikipedia
Crookes — William Crookes Sir William Crookes (* 17. Juni 1832 in London; † 4. April 1919 ebenda) war ein englischer Physiker, Chemiker, Wissenschaftsjournalist und Parapsychologe … Deutsch Wikipedia
Crookes — William Crookes William Crookes Sir William Crookes (17 juin 1832 4 avril 1919) est un chimiste et un physicien britannique qui a donné son nom à la technique des tubes dits de Crooks grâce auxquels ont été découverts par exemple les rayons X. Il … Wikipédia en Français
William Crookes — Sir William Crookes (17 juin 1832 4 avril 1919) est un chimiste et un physicien britannique qui a donné son nom à la technique des tubes de Crookes, grâce auxquels ont été découverts par exemple les rayons X. Il est également connu pour ses … Wikipédia en Français