Iron oxide catalysts supported on nanostructured silica SBA-15 were synthesized with various iron loadings using two different precursors. Structural characterization of the as-prepared Fe x O y /SBA-15 samples was performed by nitrogen physisorption, X-ray diffraction, DR-UV-Vis spectroscopy, and Mössbauer spectroscopy. An increasing size of the resulting iron species correlated with an increa...

The data for the nonisothermal and isothermal thermal decompositions of lanthanum oxalate have been analysed using model-free model-fitting kinetic techniques. When applied to Coat-Redfern(CR) equation, widely used approach that results excellent fitting both but produces very ambiguous values Arrhenius parameters. These cannot be compared those obtained from experiments. On other hand, strateg...

The kinetics of nanocrystallization of a Mn-doped FINEMET alloy from its amorphous precursor is reported. The alloy studied was of a composition (Fe1 Mn )73 5Nb3CuSi13 5B9 where = 0 05. X-ray diffraction (XRD) confirmed that -FeSi is the product of primary nanocrystallization. Crystallization kinetics were studied using time-dependent magnetization, ( ), as a measure of the volume fraction crys...

In the present work, the in¯uence of the nucleation time-lag on the non-isothermal glass crystallization is discussed. Di€erential thermal analysis (DTA) results of an iron-rich glass nucleated by Cr 2 O 3 were obtained at di€erent heating rates. The activation energy of crystallization, E c , and the Avrami parameter, m, estimated by Kissinger's and Ozawa's equations were shown to be dependent...

Three formaldehyde-based resins were prepared: urea-formaldehyde (UF) resin without melamine modifier (named UF0 resin) and melamineurea-formaldehyde (MUF) resins with melamine modifier added at two different synthesis stages (named MUF1 resin and MUF2 resin). The effects of the melamine addition stage on the performance and curing behavior of MUF resin were studied. Three-ply plywood bonded by...

High density grain boundaries provide high strength, but may introduce undesirable features, such as high Fermi levels and instability. We investigated the kinetics of recovery and recrystallization of Cu that was manufactured to include both nanotwins (NT) and high-angle columnar boundaries. We used the isothermal Johnson-Mehl-Avrami-Kolmogorov (JMAK) model to estimate activation energy values...

Seaweed has attracted considerable attention as a potential biofuel feedstock. The pyrolytic and kinetic characteristics of maize straw and the seaweed Ulva pertusa were studied and compared using heating rates of 10, 30 and 50°C min(-1) under an inert atmosphere. The activation energy, and pre-exponential factors were calculated by the Flynn-Wall-Ozawa (FWO), Kissinger-Akahira-Sunose (KAS) and...

The pyrolysis of coal (C), torrefied sawdust (SPT), paraffin (P), and their blends was evaluated. Iso-conversional methods (i.e. Friedman, Flynn-Wall-Ozawa, Kissinger-Akahira-Sunose) were used to determine the activation energy (Ea); Kissinger method allowed frequency factor (A) calculation Criado Coats-Redfern elucidate reaction mechanism. Thermodynamic parameters transition state (ΔH‡, ΔG‡ ΔS...