Manganese substitution

The physical description of strongly pressure dependent magnetic properties is the object of considerable study. Edwards and Bartel [74E01] have performed the more recent physical evaluation of strong pressure and composition dependence of magnetization in their work on cobalt and manganese substituted invars. Their work contrasts models based on a localized-electron model with a modified Zener model in which both localized- and itinerant-electron effects are incorporated in a unified model. Their work favors the latter model. 

C.E. Lundin, F.E. Lynch, Modification of hydriding properties of AB5 alloy type hexagonal alloys through manganese substitution, Proceedings of the Miami International Conference Alternate Energy Sources, United States, 5-7 December 1977. University of Miami, (1978)... 

Stiers.W. Schwertmann, U. (1985) Evidence for manganese substitution in synthetic goethite. Geochim. Cosmochim. Acta 49 1909-1911... 

Cobalt- or manganese-substituted PW12O40 and SiWiiOj9Ru(OH2)5 catalyze the oxidation of paraffins such as cyclohexane and adamantane (320, 321) as well as the epoxidation of cyclohexene with ter/-butyl hydroperoxide, iodosylbenzene potassium persulfate, and sodium periodate (321, 322). The reactivity depends on the transition metals. In the case of epoxidation of cyclohexene with iodosylbenzene, the order of catalytic activity of PW] i(M)03 is M = Co > Mn > Cu > Fe, Cr. 

Manganese-substituted Fe (III) oxyhydroxide (Mno.13Feo.87 OOH) Laboratory solutions 30-60 7.0 As(lll)... 

Ben-Daniel, R Weiner, L. and Neumann, R. (2002) Activation of nitrous oxide and selective epoxidation of alkenes catalyzed by the manganese-substituted polyoxometalate, [Mnnl2ZnW... 

As heterogeneous oxidation catalyst, 5% Pt, 1% Bi/C has been identified as an efficient catalyst for the conversion of 2-octanol to 2-octanone and 1-octanol to octanoic acid (see Fig. 4.72) [210]. Also manganese-substituted octahedral mo-... 

In contrast to its behaviour towards 02, manganese-substituted haemoglobin binds NO reversibly at room temperature. Moreover, the Mn" + NO system is isoelectronic with Fe11 + CO and has been argued to be a close model for the binding of CO to haemoglobin.503 Examples of nitrosyl adduct formation by simple Mn porphyrins have also been reported.504... 

There have in addition been numerous studies of Mn-substituted proteins. In these, Mn is substituted for a metal found naturally in the protein (most often Mg, but also Zn Ca , or Fe ). This substitution is generally used to permit spectroscopic characterization of the native metal site, using Mn as the reporter. Often (although not always) the Mn-substituted protein is active. Manganese-substituted proteins are discussed briefly where they illustrate important properties of Mn protein interactions. 

Recent EPR and ENDOR studies on the binding of manganese substituted adenosine nucleotides have been interpreted to suggest that these nucleotides may bind near the P-cluster pair (69). 

The alkaline earth hexaaluminate supports mentioned in Section 3.5.2 have been made catalytically active by the addition of transition metal ions [25]. Manganese substitution produced the highest catalytic activity. The manganese-substituted aluminates maintain high surface areas at 1000 °C (see Table 1), but their activity per unit area is so low that the activity on a per gram basis remains much lower than that of the noble metals. The same applies to the Cu/La-substituted alumina included in Table 1. Note that surface areas at 1300°C will be significantly lower... 

FISHETAL. Hydroxylation of CyCv and Cydo-Cs Hydrocarbons MANGANESE SUBSTITUTED KEGGIN IONS, MnPWn0395 ... 

Preliminary results with a manganese-substituted Keggin ion catalyst that has an extremely stable PWi 1039 - backbone (Figure 1), shows some promise with small hydrocarbons(l). This catalyst can be heated to 65 °C for long periods without decomposition. An initial experiment with ethane and t-butyl hydroperoxide in benzene gave 2 turnovers of ethane to ethanol in three hr at 65 °C, while with propane the turnover number was 24 and provided isopropanol and n-propanol in a 5 1 ratio (Table m). 

Table m. Carbon-Hydrogen Activation of C1-C3 Hydrocarbons with a Manganese-Substituted Keggin Ion Catalyst Using t-Butyl Hydroperoxide as the Monooxygen Transfer Reagent in Benzene a... 

Very recently, we have reported that <7i-manganese-substituted silicotungstate, Y-SiWio Mn (OH2))203g ... 

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