Cesium history

The history of atomic emission spectrometry (AES) goes back to Bunsen and Kirchhoff, who reported in 1860 on spectroscopic investigations of the alkali and alkali earth elements with the aid of their spectroscope [1], The elements cesium and rubidium and later on thorium and indium were also discovered on the basis of their atomic emission spectra. From these early beginnings qualitative and quantitative aspects of atomic spectrometry were considered. The occurrence of atomic spectral lines was understood as uniequivocal proof of the presence of these elements in a mixture. Bunsen and Kirchhoff in addition, however, also estimated the amounts of sodium that had to be brought into the flame to give a detectable line emission and therewith gave the basis for quantitative analyses and trace determinations with atomic spectrometry. 

The plan of this chapter is as follows. In the next section an overview of the history of the weak interactions in general, and atomic PNC in particular, is given. In section 3, Furry representation is introduced and applied to a calculation of a transition energy of a highly charged ion, Bi ". Section 4 describes the theory of cesium PNC, starting with low-order many-body perturbation theory (MBPT) methods, and then generalizing to all-orders methods based on coupled cluster theory. Section 5 closes the chapter with a brief description of the closely related field of atomic electric dipole moments. 

This lull in the history of discoveries of new elements was ended by the spectral method developed in 1859-1860 by the German scientists R. Bunsen and G. Kirchhoff. And at once reports appeared about the discovery of new elements, which announced themselves via new spectral lines. Four chemical elements (cesium, rubidium, thallium, and indium) came to light owing to the spectroscopic method. 

Eka-cesium looked totally inaccessible for artificial synthesis. No suitable targets and bombarding particles existed in the thirties. But such is the irony of history that it was precisely element 87 that became the second after technetium reliably discovered element out of the four missing elements within the old boundaries of the periodic system. 

At this point in history the line of eka-iodine and eka-cesium, which had travelled parallel for such a long time, started to diverge and therefore we shall consider their discoveries separately. 

Measure The Journal of Measurement Science 2, no. 4 (December, 2007) 74-89. Explains the history and principles behind the NIST frequency standards. Includes references, figures, tables, and color photographs of NIST cesium clocks. 

We now start a systematic chapter-by-chapter study of the eight groups of representative elements. In each of these chapters our aim is to discuss the history of the discovery of the elements, how our developing network can be applied to predict and rationalize the chemistry of the group, and what special characteristics and practical applications these elements have. We will also explore at least one special topic in depth for each group. In this chapter we discuss the alkali metals (lithium, sodium, potassium, rubidium, cesium, and francium) and add a seventh component (a knowledge of reduction potentials) to the network. The special topic in depth is liquid ammonia solutions of the Group lA and 2A metals. 

The 1986 Chernobyl explosion in Ukraine is considered to be the worst nuclear power plant disaster in history. Among other radioactive nuclides, cesium-135... 

Figure 5 shows the elemental fission product density histories at the exit of the circuit into the containment predicted by VICTORIA. Silver, indium, and cadmium releases have several peaks, which correspond to bursts of control rod segments predicted by CORSOR. Most of the fission product densities tail off at about 7000 s, which corresponds to shutdown of the reactor. However, cesium and iodine densities remain relatively high due to revaporization within the circuit. 

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