Kinetics of catalytic oxidation of methane: Application of initial rate technique for mechanism determination

A kinetic investigation on the oxidation of methane using a palladium catalyst was conducted. Conversions of methane were small and limited to about 10% to facilitate the use of initial rate approach. Plots of initial rate against total pressure and varying feed composition were used to interpret the data qualitatively. Regression coefficients from linearized rate equations and criteria of best fit were used to arrive at a plausible mechanism. The experimental results indicated that the reaction rate is controlled by surface reaction in which the adsorbed oxygen and adsorbed methane react to produce adsorbed carbon dioxide and adsorbed water.     

Pressure drop and gas bypassing in recirculating fluidized beds

The effect of different operating and design parameters on the pressure drop profile for a recirculating fluidized bed has been studied. A mathematical model was developed for the pressure drop in the recirculating fluidized bed. The different parameters considered were flow rate, inventory of solids and spacing between the draft-tube bottom and the distribution plate. Geldart D and B particles were used for the study. The gas bypassing from the jet towards the downcomer was calculated on the basis of the mathematical model and the effect of various parameters on gas bypassing were analyzed.     

Intrusion detection techniques in network environment: a systematic review

Wireless Networks - The entire world relates to some network capabilities in some way or the other. The data transmission on the network is getting more straightforward and quicker. An intrusion...     

A comparative study to evaluate the corrosion performance of Zr incorporated Cr3C2-(NiCr) coating at 900 °C

In this study zirconium incorporated Cr₃C₂-(NiCr) coating has been sprayed on three superalloys viz. Superni 718, Superni 600 and Superco 605 using D-gun technique. A comparative study has been carried out to check the cyclic oxidation in air and hot corrosion in simulated incinerator environment (40%Na₂SO₄-40%K₂SO₄-10%NaCl-10%KCl) for the coated specimens at 900 °C for 100 cycles. Oxidation kinetics has been established for all the specimens using weight change measurements. Corrosion products have been characterized using X-ray diffractometer (XRD) and scanning electron microscopy/energy-dispersive analysis (SEM/EDAX). Cr₃C₂-(NiCr) + 0.2%wtZr coating provides very good corrosion resistance in air oxidation for all the three coated superalloys. As all the three coated superalloys shows parabolic behaviour with parabolic rate constant as 0.07 × 10^?10 (g² cm^?4 s^?1) for Superni 718, 0.43 × 10^?10 (g² cm^?4 s^?1) for Superni 600 and 0.3 × 10^?10 (g² cm^?4 s^?1) for Superco 605 This coating is also effective in the molten salt environment but coating on Co-based superalloy Superco 605 did not perform satisfactorily. The parabolic rate constants for coated Superni 718 is 0.61 × 10^?10 (g² cm^?4 s^?1), for coated Superni 600 is 6.72 × 10^?10 (g² cm^?4 s^?1) and for coated Superco 605 is 17.5 × 10^?10 (g² cm^?4 s^?1).     

Experimental and theoretical investigations on the compressibility of nanocrystalline nickel

We investigated nanocrystalline nickel experimentally (x-ray diffraction) and theoretically (cluster ab initio calculations). No phase transition was observed in nano-nickel. The volume, isothermal bulk modulus and its pressure derivative derived experimentally and theoretically are 43.56 (0.13) ų, 228(15) GPa, 4.02(0.51) and 44.00 ų, 217 GPa and 3.20, respectively. We found no appreciable change in the value of bulk modulus for nano-nickel as compared to the bulk-nickel.An erratum to this article can be found at     

Improved Recognition Results of Medieval Handwritten Gurmukhi Manuscripts Using Boosting and Bagging Methodologies

Neural Processing Letters - The uniform sampling strategy is widely used in time series segmentation, but unable to handle time warping problem or preserve the latent patterns in time series. To...     

Exploring Temporal Analytics in Fog-Cloud Architecture for Smart Office HealthCare

Mobile Networks and Applications - Ever since the boost realized in Information and Communication Technology (ICT), market is flooded with high-end multi-tasking devices, presenting a real-time...     

Second-order numerator-dynamics systems: Effects of initial discontinuities

Linear second-order systems with numerator-dynamics are considered and their transient responses are investigated for discontinuous inputs. Characteristic parameters for second-order systems with numerator dynamics are identified. The solution profiles of these systems depend upon the value of one such parameter relative to that of the others on the number line. Effects of initial jump discontinuities of the inputs on the correctness of the solutions are also treated. A methodology for analysis of discontinuities is presented. Initial discontinuities of the calculated response either get accounted for in the input function or the initial condition of the input function for all but the following case. For the impulse response alone, that too among inherent numerator-dynamics systems only, an initial di scontinuity cannot be accounted for in the input. The value of that discontinuity is thus required for correct solutions of these cases. The results are general and extendable to different inputs and higher order systems.