Nickel multi-component

In the case of multi-component alloys and compounds, the surface composition may also change in addition to surface relaxation and reconstruction. For instance, the first layer of (100) plane on the surface of a nickel-aluminiim alloy enriches itself with aliuninum whose atomic size is larger than nickel. Such an enrichment of some constituents on the soUd surface is called surface segregation [Van Hove, 1993]. It is abo known that surface active minor impurities of oxygen, phosphorus and sulfur in metallic iron segregate to the clean siirface of iron [Nii-Yoshihara,... 

Chapter 10 provides an exhaustive description of how these techniques can be applied to a large number of industrial alloys and other materials. This includes a discussion of solution and substance databases and step-by-step examples of multi-component calculations. Validation of calculated equilibria in multi-component alloys is given by a detailed comparison with experimental results for a variety of steels, titanium- and nickel-base alloys. Further selected examples include the formation of deleterious phases, complex precipitation sequences, sensitivity factor analysis, intermetallic alloys, alloy design, slag, slag-metal and other complex chemical equilibria and nuclear applications. 

The formation of macrocyclic ligands by template reactions frequently involves the reaction of two difunctionalised precursors, and we have tacitly assumed that they react in a 1 1 stoichiometry to form cyclic products, or other stoichiometries to yield polymeric open-chain products. This is certainly the case in the reactions that we have presented in Figs 6-8, 6-9, 6-10, 6-12 and 6-13. However, it is also possible for the difunctionalised species to react in other stoichiometries to yield discrete cyclic products, and it is not necessary to limit the cyclisation to the formal reaction of just one or two components. This is represented schematically in Fig. 6-19 and we have already observed chemical examples in Figs 6-4, 6-11 and 6-18. We have already noted the condensation of two molecules of 1,2-diaminoethane with four molecules of acetone in the presence of nickel(n) to give a tetraaza-macrocycle. Why does this particular combination of reagents work Again, why are cyclic products obtained in relatively good yield from these multi-component reactions, rather than the (perhaps) expected acyclic complexes We will try to answer these questions shortly. 

It was also found that the multi-component catalyst system performed essentially identically to naked nickel in terms of molecular weight control upon addition of the chain transfer agent 1-decene (see Fig. 4.23 and compare to Fig. 4.12). 

Moreover, the microstructure of the norbornene homopolymer that is formed using this multi-component catalyst is identical to that produced by naked nickel as evidenced by and NMR spectroscopy. Based on these observations, it is clear that the active catalyst formed in situ from the multi-component system is very similar to the naked nickel single component catalyst [50]. 

The (co-)polymerization of functional monomers was also explored with the Ni and Pd catalyst systems. The multi-component Ni catalyst (Ni(O2CR)2 -i-HSbFg-i-OBFs LlyO-i-lOAlLlj) works very well for the copolymerization of norbornene and 5-triefhoxysilylnorbornene. The copolymerization of norbornene and with 5-10 mol% 5-triethoxysilylnorbomene monomers yields a high molecular weight copolymer of fhe same molar composition in excellent yield (85%) at a 4000 1 monomer to nickel molar ratio. 

Redox non-innocent ligands have also been employed in other kinds of processes. For example, a nickel-based system has been used in the purification of ethene gas streams [41]. The two forms (reduced and oxidized) of the dithiolene complex have different affinities for olefin, leading to separation of ethene from gas mixtures (Scheme 14). Intermediate 47 is obtained after electrochemical oxidation of the anionic nickel complex 46. The oxidized complex 47 reacts selectively with ethylene to form the adduct 48, thus the non-olefinic contamination of the multi-component stream... 

Much of the literature on heavy-metal-bearing soils and sediments has been devoted to the speciation of anthropogenic metal(oid)s in contaminated matrices, but few papers focus on their crystal chemistry when they are present in trace amounts. This section reviews this topic and supplements and enhances the existing literature by describing the forms of arsenic, selenium, nickel, and zinc in two natural soils. It also attempts to illustrate with one example (Zn) how the novel synergistic use of pSXRF, pSXRD, and pEXAFS provides a quantitative analytical tool to speciate dilute multi-component metals in heterogeneous environmental materials. 

Nickel-catalyzed highly regioselective multi-component coupling of ynamides, aldehydes and silane a new access to functionalized enamides. Propargyl alcohols (b) H. A. Malik, M. R. Chaulagain, J. Montgomery, Org. Lett. 2009,... 

The nickel base alloys are typically singlephase, multi-component and contain iron and chromium. Carbon is present in the range of 0.03-0.08 wt%. From several investigations, it is clear that chromium increases the corrosion resistance of nickel base alloys by virtue of formation of a passive film containing chromium. Inconel... 

Following the publication of a first set of four volumes of SGTE compiled thermodynamic properties of inorganic substances, which dealt with pure substances (Subvolume A), this second set of four volumes presents selected thermodynamic data for binary alloy systems (Subvolume B). The possibility to continue to ternary and multi-component systems is also foreseen. The data in the latter would be so presented as to correspond to potential application themes (steels, light alloys, nickel-base alloys, etc.). The fundamental equations used in evaluating the data are given in the introduction to the volumes and the models used in representing the data are also described. 

Bio-oil reforming requires a multi-functional catalyst which can (1) steam reform the oil organic components into carbon dioxide (CO2), carbon monoxide (CO) and H2 (2) shift the produced CO with steam to make more CO2 and H2 (3) gasify carbonaceous residues formed on the catalyst surface mostly from non-volatile bio-oil components and (4) resist attrition. CoorsTek Ceramics produces spherical aluminas, with a range of physical properties, which could meet these requirements. Nickel-based catalysts, the most widely used shift... 

Two points stand out with regard to the two multi-city studies. First, PM2 5 components such as BC (black carbon) or EC (elemental carbon, virtually the same as BC), OC (organic carbon), and metals (such as iron [Fe], nickel (Ni], and vanadium [V]) are not monitored. Secondly, these studies find health associations with sulfate, the only PM2.5 species monitored by both studies. 

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