Ruthenium Ru

The characteristic mass at the main absorption line, using a transversely heated graphite tube atomizer, is mo = l-6pg. The sensitivity obtained with HR-CS AAS, both in a flame and in the graphite furnace, is significantly better than that with LS AAS. A few less sensitive analytical lines that might be used for the determination of higher rubidium concentrations are compiled in Table 6.22 together with information about their spectral environment. 

The most sensitive analytical line for ruthenium is at 349.895 nm with a characteristic concentration of cq = 0.8mg/L in an air/acetylene flame. The characteristic mass at this line, using a transversely heated graphite tube atomizer, is mo = 40 pg. No further information is available about this element. 

The 90-keV resonance in Ru was first reported in 1963, by Kistner, Monaro, and Segnan [20]. The first excited level is populated by a complicated EC decay of 16-day Rh (see Fig. 16.7). The latter is prepared by a Ru(p, ) Rh cyclotron irradiation [20, 21], or by the alternative Ru( /, 2 ) Rh reaction [22], both of which are expensive in relation to the usable lifetime of the source. Matrices of natural or enriched ruthenium metal can be irradiated and used directly, although a process for chemical separation of the Rh activity followed by re-incorporation into ruthenium metal has been described [23]. 

Ruthenium metal has a hexagonal symmetry, but the source/absorber combination gives a linewidth of about 0-24 mm s , which is not substantially greater than the natural width of 0-15 mm s [21]. 

The use of polarised magnetic spectra from Ru in iron metal for studies on time-reversal invariance, although extremely interesting, is beyond our present scope [21, 24, 25]. 

The early work by Kistner showed partially resolved quadrupole splittings and large chemical isomer shifts in RUO2 and Ru( i-C5H5)2 [21]. More 

The quadrupole moment of the excited state is at least a factor of 3 greater than that for the ground state. This results in an apparent doublet spectrum 

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Hydrogenation of olefinic unsaturation using ruthenium (Ru) catalyst is well known. It has been widely used for NBR hydrogenation. Various complexes of Ru has been developed as a practical alternative of Rh complexes since the cost of Ru is one-thirtieth of Rh. However, they are slightly inferior in activity and selectivity when compared with Rh catalyst. 

The goal of Haber s research was to find a catalyst to synthesize ammonia at a reasonable rate without going to very high temperatures. These days two different catalysts are used. One consists of a mixture of iron, potassium oxide. K20, and aluminum oxide. Al203. The other, which uses finely divided ruthenium, Ru. metal on a graphite surface, is less susceptible to poisoning by impurities. Reaction takes place at 450°C and a pressure of 200 to 600 atm. The ammonia... 

Black-brown RuBr3 has roughly octahedral coordination of ruthenium (Ru-Br 2.46-2.54 A) with short Ru-Ru contacts (2.73 A) [17]. Black Rul3 has a similar structure. Neither is particularly soluble in water. 

A particularly interesting case is that of the platinum metal group which, in addition to platinum (Pt), comprises ruthenium (Ru), osmium (Os), rhodium (Rh), iridium (Ir), and palladium (Pd). These carbonyl halides are usually the most practical precursors for metal deposition because of their high volatility at low temperature. Indeed two of them, palladium and platinum, do not form carbonyls but only carbonyl halides. So does gold. 

The platinum-group metals comprise ruthenium (Ru), rhodium (Rh) and palladium (Pd) from the second transition series and osmium (Os), iridium(Ir), and platinum (Pt) from thethird transition series. Little or no C VD investigation of palladium and osmium have been reported and these metalsarenotincludedhere. The properties of the other platinum-group metals are summarized in Table 6.9. 

Recently, Newkome et al. [165] described the synthesis of dendritic lock and key complexes, such as 78, which is based on the well-researched bzsterpyridine-ruthenium (—(Ru)—) coordination chemistry (Fig. 33). Dendritic terpyridines of the first and second generation were reacted with RuC13 and this formed the... 

The feasibility of carbon-supported nickel-based catalysts as the alternative to the platinum catalyst is studied in this chapter. Carbon-supported nickel (Ni/C, 10 wt-metal% [12]), ruthenium (Ru/C, 10 wt-metal% [12]), and nickel-ruthenium composite (Ni-Ru/C, 10 wt-metal%, mixed molar ratio of Ni/Ru 0.25,1,4, 8, and 16 [12]) catalysts were prepared similarly by the impregnation method. Granular powders of the activated carbon without the base pretreatment were stirred with the NiCl2, RuC13, and NiCl2-RuCl3 aqueous solutions at room temperature for 24 h, respectively. Reduction and washing were carried out in the same way as done for the Pt/C catalyst. Finally, these nickel-based catalysts were evacuated at 70°C for 10 h. 

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