Caesium alloy

Range of application and spectral sensitivity The photomultiphers most frequently employed in scanners possess antimony-caesium cathodes. These alloy cathodes are primarily sensitive to the short-wavelength part of visible light (Tab. 4). 

Use of potassium graphite or caesium graphite to generate methylborylene is uneventful, while use of sodium-potassium alloy (1 5 mol) caused an explosion in 2 out of 5 attempts. 

Pelton, A.D. (1987) The Au-Cs (Gold Caesium) system. In Phase Diagrams of Binary Gold Alloys, eds. Okamoto, H. and Massalski,T. (ASM International, Metals Park, USA), p. 72. 

The collected papers of a symposium at Dallas, April 1956, cover all aspects of the handling, use and hazards of lithium, sodium, potassium, their alloys, oxides and hydrides, in 19 chapters [1], Interaction of all 5 alkali metals with water under various circumstances has been discussed comparatively [2], In a monograph covering properties, preparation, handling and applications of the enhanced reactivity of metals dispersed finely in hydrocarbon diluents, the hazardous nature of potassium dispersions, and especially of rubidium and caesium dispersions is stressed [3], Alkaline-earth metal dispersions are of relatively low hazard. Safety practices for small-scale storage, handling, heating and reactions of lithium potassium and sodium with water are reviewed [4],... 

Moissan 7 found that the hydrides of lithium, sodium, potassium, rubidium, and caesium are non-conductors of electricity, and therefore cannot be regarded as alloys. He considered that in these compounds hydrogen has a metalloidic character, and that it is not comparable with the metals, an argument against its inclusion in Group I.8... 

The metals are employed in a variety of alloys. Lithium generally hardens and strengthens, but also causes embrittlement from 0.05 to 0.1% is used in Al, Zn and Mg alloys. Sodium is an important additive to lead such an alloy is the basis of the manufacture of lead tetraethyl, and another, containing 0.6% Na, 0.6% Ca and 0.05% Li, is a bearing metal. Ternary alloys of caesium with aluminium and either barium or strontium are used in photoelectric cells. Liquid sodium or sodium-potassium alloy is employed to transfer heat from the core of certain atomic reactors, e.g. Dounreay fast breeder. 

The structure of caesium chloride is included here because, although it is not close packed, it is often confused with, and written as, body centred when it is not. The structure of caesium chloride is shown in Figure 1.17. The chloride ions are on the cube comers and the ion at the centre is a caesium. In Section 1.4 we saw that a body-centred cubic lattice refers to an identical set of points with identical atoms at the comers and at the centre of the cube. This means that the stmcture of caesium chloride is not body-centred cubic. Many alloys, such as brass (copper and zinc) possess the caesium chloride structure. 

The simpler of these two structures is the caesium chloride arrangement, found in the phases LiHg, LiTl, MgTl, CaTl and SrTl. This is, of course, also the structure of the / phase in the silver-cadmium system and in other electron compounds (fig. 13.11), and for this reason the systems just mentioned are sometimes quoted as exceptions to Hume-Rothery s rule. Apart from this geometrical resemblance, however, these systems have little in common with the electron compounds, and it seems preferable to regard the Hume-Rothery rule as applicable only to alloys of the T2-B1 type. 

Rubidium alloys used in research to mimic the properties of caesium, a rarer metal. 

Sodium, Potassium, Rubidium, and Caesium.— The synthesis of l,4,l, 4 -tetra-hydrobiphenyl by low-temperature reduction of benzene with Cs-K-Na alloy and subsequent hydrolysis is possibly the best method to date for the preparation of this compound. Two new formyl carbanion equivalents, with Na counter-ions rather than the more common Li", have been acclaimed. One is based on a-tosylmethyl isocyanide, and the other, which gives lower product yields, is based on N-nitromethylphthalimide. 

Biofilm formation at the air-water interface. The bathtub ring often formed at the air-water interface around the sides of the basin is likely to be a biofilm due to microbial activity. This film acts like a trap and is known to concentrate caesium and other radioactive isotopes contained in the basin water. This biofilm should be removed mechanically by wet brushing, using water to hold down any airborne activity. A 35% solution of hydrogen peroxide has proven effective in suppressing microbial activity and could be used to assist in biofilm removal without corrosive attack on aluminium alloys. 

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