Parent metal

The photoaggregation technique has been extended to the Ag/Cr system (116), where the naked, bimetallic species AgCr and Ag Cr can be selectively photogenerated, and identified, in the presence of the uni-metallic, parent clusters, with photoselectivity reminiscent of that of the Cr/Mo system 115). A typical trace is shown in Fig. 24. 

M M MCPBA Me MNDO MS metal parent molecule m-chloroperbenzoic acid methyl modified neglect of diatomic overlap mass spectrum... 

In summary, the preparation of bimetallic catalysts by surface redox reaction using a reductant preadsorbed on the parent monometallic catalyst has been studied in detail. Unfortunately, the method is intricate and time consuming, especially if several successive operations are required. Furthermore, when the modifier has a standard electrochemical potential higher than that of the parent metal (AUCI4 deposited on Pt°), the overall reaction is a complex one involving a reduction by adsorbed reductant but also direct oxidation of the metallic parent catalyst. The relative rate of the two parallel reactions determines the catalytic properties of the resulting bimetallic catalyst. 

For multiply metalated parent hydrides in particular another naming method borrowed from inorganic nomenclature can also be applied hereby metal substituents are expressed in the form of metalio prefixes, e.g. ... 

M.p. 296 C. Accepts an electron from suitable donors forming a radical anion. Used for colorimetric determination of free radical precursors, replacement of Mn02 in aluminium solid electrolytic capacitors, construction of heat-sensitive resistors and ion-specific electrodes and for inducing radical polymerizations. The charge transfer complexes it forms with certain donors behave electrically like metals with anisotropic conductivity. Like tetracyanoethylene it belongs to a class of compounds called rr-acids. tetracyclines An important group of antibiotics isolated from Streptomyces spp., having structures based on a naphthacene skeleton. Tetracycline, the parent compound, has the structure ... 

Parent D C and Anderson S L 1992 Chemistry of metal and semimetal cluster ions Chem. Rev. 92 1541... 

Generally the solubility of a given metal halate decreases from chlorate(V) to iodatef and many heavy metal iodates(V) are quantitatively insoluble. Like their parent acids, the halates(V) are strong oxidising agents, especially in acid solution their standard electrode potentials are given below (in volts) ... 

I he results of their calculations were summarised in two rules. The first rule states that at least one isomer C with a properly closed p shell (i.e. bonding HOMO, antibonding I. U.MO) exists for all n = 60 - - 6k (k = 0,2,3,..., but not 1). Thus Qg, C72, Cyg, etc., are in lhi-< group. The second rule is for carbon cylinders and states that a closed-shell structure is lound for n = 2p(7 - - 3fc) (for all k). C70 is the parent of this family. The calculations Were extended to cover different types of structure and fullerenes doped with metals. 

Alloys with other useful properties can be obtained by using yttrium as an additive. The metal can be used as a deoxidizer for vanadium and other nonferrous metals. The metal has a low cross section for nuclear capture. 90Y, one of the isotopes of yttrium, exists in equilibrium with its parent 90Sr, a product of nuclear explosions. Yttrium has been considered for use as a nodulizer for producing nodular cast iron, in which the graphite forms compact nodules instead of the usual flakes. Such iron has increased ductility. 

The base peak in the mass spectrum of the LM free metal-ligand ion and the fragmentation patterns of this parent ion are of particuliar significance since they illustrate the effect of coordination upon the properties of the thiazole ligand. The free thiazole fragments upon electron impact by two major routes (Scheme 86 also cf. Section II. 6). 

Organometallic compounds are named as substituted derivatives of metals The metal is the parent and the attached alkyl groups are identified by the appropriate prefix... 

Fig. 2. The plot of total reduced iron, Fe, and oxidized iron, Fe, normalized to Si abundance shows how the chondrite classes fall into groups distinguished by oxidation state and total Fe Si ratio. The soHd diagonal lines delineate compositions having constant total Fe Si ratios of 0.6 and 0.8. The fractionation of total Fe Si is likely the result of the relative efficiencies of accumulation of metal and siUcate materials into the meteorite parent bodies. The variation in oxidation state is the result of conditions in the solar nebula when the soHds last reacted with gas. Terms are defined in Table 1 (3).

Stony Irons. The stony iron meteorites are composed of substantial iron and siUcate components. The paHasites contain cm-sized ohvine crystals embedded ia a soHd FeNi metal matrix and have properties consistent with formation at the core mantle boundary of differentiated asteroids. The mesosiderites are composed of metal and siUcates that were fractured and remixed, presumably ia the near-surface regions of their parent bodies. 

Trunsition-MetnlHydrides, Tiansition-metal hydiides, ie, inteistitial metal hydrides, have metalhc properties, conduct electricity, and ate less dense than the parent metal. Metal valence electrons are involved in both the hydrogen and metal bonds. Compositions can vary within limits and stoichiometry may not always be a simple numerical proportion. These hydrides are much harder and more brittie than the parent metal, and most have catalytic activity. 

The parent acid of the hexakiscyanoferrate(3—) salts is ferricyanic acid [17126464] (trihydrogen hexakiscyanoferrate). Red-brown needles are obtained by evaporation of solutions prepared by adding sulfuric acid to tribarium bis(hexakiscyanoferrate). The acid is used to prevent metal surface corrosion. 

Destructive Testing. Destmctive testing is used to determine the strength of the weld and the effect of the explosion-welding process on the parent metals. Standard testing techniques can be utilized on many composites however, nonstandard or specially designed tests often are required to provide meaningful data for specific appHcations. 

Hydroxyapatite, Ca2Q(PO (OH)2, may be regarded as the parent member of a whole series of stmcturaHy related calcium phosphates that can be represented by the formula M2q(ZO X2, where M is a metal or H O" Z is P, As, Si, Ga, S, or Cr and X is OH, F, Cl, Br, 1/2 CO, etc. The apatite compounds all exhibit the same type of hexagonal crystal stmcture. Included are a series of naturally occurring minerals, synthetic salts, and precipitated hydroxyapatites. Highly substituted apatites such as FrancoHte, Ca2Q(PO (C02) (F,0H)2, are the principal component of phosphate rock used for the production of both wet-process and furnace-process phosphoric acid. 

Historically, potassium metal was used by the Mine Safety AppHances Company (parent company of Gallery Chemical Company) to develop potassium superoxide [12030-88-5] oxygen source in self-contained breathing equipment (see Oxygen-GENERATION systems). Greater understanding... 

Chrome dyes are acid dyes (mol wt 300—600) that contain groups capable of forming complexes by reaction with a metal salt, usually sodium or potassium dichromate (94,97). The chrome/dye complex has lower solubiUty, and hence better wetfastness, than the parent dyestuff. Reaction between the... 

Alkali Metal Hydroxides. Addition of base to aqueous chloroformates cataly2es hydrolysis to yield the parent hydroxy compound (11). However, the use of a stoichiometric amount of alkaU metal hydroxides can lead to the symmetrical carbonate, especially from aryl chloroformates (12,13). 

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