Fe/Si molar ratio

Independent of Fe Si molar ratio. Charging curves from fast titration experiments in 0.001—0.1 M NaNO, are also reported (also at 3O-5O°C), and their results are unusual ((Jq decreases with ionic strength). 

A magneto-optical method to measure the particle size using the Faraday effect has been developed in samples with the same Fe/Si molar ratio but different diameters of the magnetic nanoparticles. The increase of Faraday rotation with the mean diameter of the y-Fe203particles was associated with surface effects [43]. 

The surface silylated zeolites were prepared by suspending the H-ZSM-5 or FeH-ZSM-5 zeolite in n-hexane into which a calculated amount of tetraethyl orthosilicate was added to obtain addition of 1.5 wt. % of Si in the final product (abbrev. SiH-ZSM-5 or SiFeH-ZSM-5). n-Hexane was evaporated and the zeolites were dried and calcined in an oxygen stream at 770 K for 5 hours. To add some Fe cations to the surface of silylated zeolites, the SiH-ZSM-5 was introduced into a FeCl solution, filtered and dried (abbrev. FeSiH-ZSM-5). The characteristics of the parent and modified zeolites are given in the Table. The alkylation of toluene with ethylene was carried out in a vapour phase continuous flow microreactor at atmospheric pressure. Nitrogen as a carrier gas was saturated with toluene to 18.5 vol. %, the toluene to ethylene molar ratio was 3.8. The reaction products were analyzed by an "on-line" gas chromatograph (Hewlett-Packard 5890) with MS and FID detection. 

MFI zeolite upon alkaline treatment (see also Fig. 1) [6]. Following those results, an optimal framework Si/Al ratio of 25-50 for mesopore formation has been established. The fitting of the data in the range Si/Al ratio 50-200 was somehow arbitrary, due to lack of zeolites with a suitable Si/Al ratio. The increased mesopore surface area of 120 m g obtained upon desilication of FeS, coupled to a framework Si/Fe molar ratio of 77, however perfectly correlates with the previously proposed fitting, despite the different nature of the trivalent framework cation (solid circle in Fig. la). Additionally, the newly created mesoporosity centered around 20 nm also agrees well with the mesopore size vs. Si/Al ratio dependency, as shown in Fig. lb. These results provide supplementary convincing evidence of the crucial role of the trivalent metal cation in framework positions on the mesopore formation process, which appears to be independent on the nature of the trivalent metal cation. In addition, this confirms the universality of the pore formation mechanism as previously proposed for the alkaline treatment of MFI zeolites [18]. 

Most TUD-1 variants are either Si-TUD-1 or an M-Si version where M is another element (e.g., Ti, Al, Cr, Fe, Zr, Ga, Sn, Co, Mo, V, etc.). Non-siliceous versions of Al- and Ti-TUD-1 have also been made. The typical Si02/ MxOy molar ratio is normally 20-oo. 

The functionalization studies of sp carbon centers in cycloalkanes and alkylbenzenes (Fig. 5.3) with hydrogen peroxide were carried out in acetonitrile, under homogeneous conditions, using various POMs, namely the tetrabutylammonium (TBA) salts of the heteropolyanions [XWiiM(H20)039] (XWnM), where X = P, Si, or B and M = Fe or Mn and [M4(H20)2(PW9034)2] , Where M = Co , Mn , and Fe (M4(PW9)2). The influence of the substrate/catalyst (S/C) molar ratio, the amount of oxidant added, or the reaction time was investigated. 

Specific Surface Area Average Particle size Density Si/Fe molar ratio... 

Fe-TON (Fe-ZSM-22) zeolites of different Si/Fe ratios (27, 36, 50, and 150) were synthesized hydrothermally using 1-ethylpirydinium bromide (EtPBr) as template. The syntheses were carried out following the procedure reported in Ref [7]. The molar composition of gels used for the syntheses was ... 

The data set of rcxzket motor features consisted of 14 elemental rcxzket propellant compositions and 4 rocket motor design parameters. The elemental compositions were molar values calculated from a 100 kg basis and included the elements C, H, O, N, Al, K, F, Cu, Pb, S, Cl, Si, Ti and Fe. The design parameters consisted of the nozzle throat temperature (Tc), pressure (Pc), nozzle diameter (Dr) and the expansion ratio of the outlet nozzle diameter to the nozzle throat diameter (Ec). 

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