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Binary transition metal ferrite (BTMF) nanocrystals of formula MFe 2 O 4 (M ¼ Cu, Co, Ni) were prepared by the coprecipitation method and characterized by X-ray diffraction (XRD). XRD patterns gave average particle size by using Scherrers equation for CuFe 2 O 4 (CuF), CoFe 2 O 4 (CoF), and NiFe 2 O 4 (NiF) as 39.9, 27.3, and 43.8 nm, respectively. The catalytic activity measurements on the thermal decomposition of ammonium perchlorate (AP) were carried out by using thermogravimetry (TG), differential thermal analysis (DTA), and ignition delay studies. Isothermal TG data up to a mass loss of 45% have been used to evaluate kinetic parameters by using model fitting as well as isoconversional method. The order of catalytic activity was found to be:

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Viscosities at 303.15 K have been measured for binary liquid mixtures of trichloroethylene (C2HC13) with benzene, toluene, p-xylene, carbon tetrachloride, and chloroform. The viscosity data have been analyzed in the light of absolute reaction rate and free volume theories of liquid viscosity, and it has been found that for the present mixtures the experimental viscosities are best reproduced by entropic and free volume corrections to ideal mixture viscosity. The enthalpic or free energy corrections to ideal mixture viscosity and the combination of free volume and reaction rate theories reproduce the experimental viscosities with the same degree of accuracy as that in the case of entropic or free-volume corrections for the systems C2HC13-CC14 and C2HC13-CHC13 only, whereas larger deviations are found for systems of CpHC13 with C6H6, C6H5CH3, and P-C~H,(CH~)~. The values of the quantity qE, which refer to the deviations from the rectilinear dependence of viscosity q of the mixture on mole fraction, have been calculated. Also the values of the parameter d have been calculated from the expression In q = x1 In q1 + x 2 In q2 + x1x2d, where q1 and q2 are the viscosities of pure components 1 and 2, whose mole fractions in the mixture are represented by x1 and xp, respectively. The values of both qE and d show that the interaction of C2HC13 becomes stronger with the aromatic hydrocarbon having an increased number of CH3 substituents attached to the aromatic ring. The slightly positive values of both qE and d for the system C2HC13-CHC13 have been attributed to the formation of a weak hydrogen bond between CHC13 and C2HClB. The values of d for the systems C2HC13-C& and CpHCl3-CCl4 indicate that C2HC13 interacts with C6H6 as strongly as it interacts with CCl,.