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Lockyer

Gr. helios, the sun). Janssen obtained the first evidence of helium during the solar eclipse of 1868 when he detected a new line in the solar spectrum. Lockyer and Frankland suggested the name helium for the new element. In 1895 Ramsay discovered helium in the uranium mineral clevite while it was independently discovered in cleveite by the Swedish chemists Cleve and Langlet at about the same time. Rutherford and Royds in 1907 demonstrated that alpha particles are helium nuclei. [Pg.6]

The focus of this section is the emission of ultraviolet and visible radiation following thermal or electrical excitation of atoms. Atomic emission spectroscopy has a long history. Qualitative applications based on the color of flames were used in the smelting of ores as early as 1550 and were more fully developed around 1830 with the observation of atomic spectra generated by flame emission and spark emission.Quantitative applications based on the atomic emission from electrical sparks were developed by Norman Lockyer (1836-1920) in the early 1870s, and quantitative applications based on flame emission were pioneered by IT. G. Lunde-gardh in 1930. Atomic emission based on emission from a plasma was introduced in 1964. [Pg.434]

The eventual resolution of the issue was that argon was fitted into a new group within the table, between the halogens and the alkali metals. In the meantime, the properties were being investigated of a gas first detected in 1868 by Frankland and Lockyer by spectroscopic analysis of solar radiation. Shortly after the argon episode, it was discovered that this gas, appropriately named helium , could be... [Pg.82]

Dithiolium salts and dithio- 3-diketone complexes of the transition metals. T. N. Lockyer and R. L. Martin, Prog. Inorg. Chem., 1980, 27, 223-324 (198). [Pg.31]

Astronomers use spectroscopy to identify the composition of the sun and other stars. A striking example is the discovery of the element helium. In 1868, astrono-mers viewing a solar eclipse observed emission lines that did not match any known element. The English astronomer Joseph Lockyer attributed these lines to a new element that he named helium, from hellos, the Greek word for the sun. For 25 years the only evidence for the existence of helium was these solar spectral lines. [Pg.461]

Observed in the spectrum of sunlight by Pierre Jules Cesar Jansen (1824-1908) as well as by Norman Lockyer (1836-1920) and Edward Frankland (1825-1899). They believed the element to be a metal. [Pg.31]

The development of chemistry itself has progressed significantly by analytical findings over several centuries. Fundamental knowledge of general chemistry is based on analytical studies, the laws of simple and multiple proportions as well as the law of mass action. Most of the chemical elements have been discovered by the application of analytical chemistry, at first by means of chemical methods, but in the last 150 years mainly by physical methods. Especially spectacular were the spectroscopic discoveries of rubidium and caesium by Bunsen and Kirchhoff, indium by Reich and Richter, helium by Janssen, Lockyer, and Frankland, and rhenium by Noddack and Tacke. Also, nuclear fission became evident as Hahn and Strassmann carefully analyzed the products of neutron-bombarded uranium. [Pg.29]

In 1908, Kamerling-Onnes got the liquefaction of helium (discovered by Janssen e Lockyer during the solar eclipse of 18 August 1868). Kamerlingh-Onnes obtained in Leiden 60 cc of liquid helium extracted from several tons of monazite sable imported from India. Kamerlingh-Onnes himself discovered the X-transition and the superfluidity in 4He and in 1911 the superconductivity of Hg, a particularly pure substance at that time. In the race towards lower and lower temperatures, Kamerling-Onnes, pumping on liquid 4He, obtained 0.7K in 1926. [Pg.54]

Unfortunately, the Schrodinger equation for multi-electron atoms and, for that matter, all molecules cannot be solved exactly and does not lead to an analogous expression to Equation 4.5 for the quantised energy levels. Even for simple atoms such as sodium the number of interactions between the particles increases rapidly. Sodium contains 11 electrons and so the correct quantum mechanical description of the atom has to include 11 nucleus-electron interactions, 55 electron-electron repulsion interactions and the correct description of the kinetic energy of the nucleus and the electrons - a further 12 terms in the Hamiltonian. The analysis of many-electron atomic spectra is complicated and beyond the scope of this book, but it was one such analysis performed by Sir Norman Lockyer that led to the discovery of helium on the Sun before it was discovered on the Earth. [Pg.100]

Schafer, E.W., Jr., R.B. Brunton, N.F. Lockyer, and J.W. DeGrazio. 1973. Comparative toxicity of seventeen pesticides to the quelea, house sparrow, and red-winged blackbird. Toxicol. Appl. Pharmacol. 26 154-157. [Pg.826]

J. Janssen and N. Lockyer independently discover helium from yellow emission line ( D3 ) in spectrum of prominence seen at eclipse. [Pg.399]

LOCKYER, D.R. (1984). A system for the measurement of field losses of ammonia through volatilisation. Journal of the Science of Food and Agriculture 35, 837-848. [Pg.44]

RYDEN, J.C., LOCKYER, D.R. andERISTOW, A.W. (1984). Circulation of mineral elements within the environment of forage plants. Nitrogen. Annual Report... [Pg.44]

RYDEN, J.C. and LOCKYER, D.R. (1985). Fate of nitrogen following land application of slurry. Annual Report 1984-85, Hurley, The Grassland Research Institute (in press). [Pg.45]

Helium - the atomic number is 2 and the chemical symbol is He. The name derives from the Greek helios for sun . The element was discovered by spectroscopy during a solar eclipse in the sun s chromosphere by the French astronomer Pierre-Jules-Cesar Janssen in 1868. It was independently discovered and named helium by the English astronomer Joseph Norman Lockyer. It was thought to be only a solar constituent until it was later found to be identical to the helium in the uranium ore cleveite by the Scottish chemist William Ramsay in 1895. Ramsay originally called his gas krypton, until it was identified as helium. The Swedish chemists Per Theodore Cleve and Nils Abraham Langet independently found helium in cleveite at about the same time. [Pg.11]

A similar California case (Kasler v. Lockyer, Cal. 4th [2000]) also included a claim that the state s assault weapons law violated the Second Amendment. However, the Ninth Circuit Court of Appeals in upholding the law also ruled that because the Second Amendment does not confer an individual right to own or possess arms, we affirm the dismissal of all claims brought pursuant to that constitutional provision. ... [Pg.91]


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See also in sourсe #XX -- [ Pg.399 ]

See also in sourсe #XX -- [ Pg.518 ]




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Lockyer, Joseph

Lockyer, Joseph Norman

Lockyer. Norman

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