The Effect of Sulphur on the Activity of Pd/Al2O3, Pd/CeO2 and Pd/ZrO2 Diesel Exhaust Gas Catalysts

Pd/Al₂O₃, Pd/CeO₂ and Pd/ZrO₂ diesel oxidation catalysts and their washcoat materials were studied after sulphur treatment. The catalytic activities were analysed in simplified diesel exhaust gas composition by FT-IR technique. ICP-OES or XRF, physisorption and CO chemisorption was used to catalyst characterisation. The result shows that the sulphur treatment clearly deactivates the studied catalysts.     

Photocatalytic water oxidation at bismuth vanadate thin film electrodes grown by direct liquid injection chemical vapor deposition method

Photoelectrochemical cells (PECs) are devices that can harvest and convert solar energy to produce consumable fuel, e.g. by splitting water into oxygen and hydrogen. Photocatalytic semiconductor materials play a major role in PECs, and their overall efficiency is usually limited by short carrier diffusion length because of structural defects, poor light absorptivity, and sluggish kinetics of photoelectrochemical reactions at the semiconductor electrode. Synthesis of high quality defect-free semiconductor materials using high temperature deposition techniques generally yield films with good adhesion to substrates while improving charge carrier transport and hence the overall efficiency of a PEC. A direct liquid injection chemical vapor deposition (DLI-CVD) technique has been utilized to synthesize monoclinic clinobisvanite phase bismuth vanadate (BiVO₄) films for photocatalytic water oxidation. The technique yields dense high quality epitaxial and polycrystalline BiVO₄ films on Yttria stabilized zirconia (YSZ) and Fluorine doped tin oxide (FTO) substrates, respectively, at growth temperature in the range of 500–550 °C. The photoelectrochemical characteristics of the films grown on FTO have been studied and a photocurrent value of 2.1 mA/cm² at 1.23 V vs Normal hydrogen electrode (NHE) (0.5 V vs. Ag/AgCl), with onset potential values as low as 0.23 V vs. NHE (?0.5 V vs. Ag/AgCl), are obtained despite the low porosity of the films. The PEC performance is further improved by synthesizing BiVO₄ directly on top of a tungsten oxide interlayer and modifying its surface with FeOOH co-catalyst.     

Utilization of Tender Coconut Pulp for Jam Making and Its Quality Evaluation During Storage

An attempt was made to utilize the residual coconut pulp left in the tender coconuts after removal of coconut water. The coconut pulp was mixed with pineapple pulp in different proportions to increase the acceptability of the jam. An increase in the level of coconut pulp was found to significantly (p?<?0.05) increase the fat content as well as Na, K, and Ca contents in the jam. Texture profile analysis revealed a significant (p?<?0.05) decrease in hardness whereas adhesiveness, springiness, cohesiveness, gumminess, and chewiness increased significantly (p?<?0.05) with an increase in the level of coconut pulp in the jam affecting its setting quality. The L* and a* values were found to increase significantly (p?<?0.05), whereas b* values decreased significantly (p?<?0.05) with an increase in the tender coconut pulp level. The jam containing 75 % tender coconut pulp and 25 % pineapple pulp showed a maximum sensory acceptability for the mixed jam. The jam prepared at optimum conditions of coconut and pineapple pulp showed a good sensory acceptability after 6 months of storage at 28?±?2 and 37 °C storage conditions on the basis of physicochemical and sensory attributes.     

Fuel cell power conditioning unit for standalone application with real time validation

In recent era, fuel cells are emerging as better alternative to wind and solar based energy sources due to its reliability and high efficiency. Polymer Electrolyte Membrane Fuel Cell (PEMFC) is widely used in various applications due to low operating temperature and high energy density. On the other side low and unregulated stack voltage demands PEMFC integration with suitable power conditioning unit. However, the use of actual fuel cell power conditioning unit in design and testing for research is expensive. Any failure may lead to damage of source or power circuit. In this regard, the present work aims at developing a soft-computing model of PEMFC. Also, a DC-DC converter is designed to step-up the stack voltage. A classical PI controller is implemented to regulate the PEMFC fed power conditioning units for resistive loads. The proposed system is implemented is Hardware-In-the-Loop (HIL) using OPAL-RT's OP5600 Real Time Digital Simulator (RTDS).     

Unsteady squeezed Casson nanofluid flow by considering the slip condition and time-dependent magnetic field

The present flow problem investigates the incompressible and squeezed flow between two parallel plates. The mathematical formulation includes the constitutive equations of Casson nanofluid, which is treated as a lubricant. Brownian movement, slip condition, and thermophoretic mechanisms are also considered. The formulated model is tackled by Runge-Kutta-Fehlberg fourth- and fifth-order numerical scheme joint with shooting criteria. Momentum, thermal, and mass species behavior is executed by plots of distinct physical constraints values. It is found that the velocity component is boosted for the larger squeezed parameter whereas the temperature component shows the same behavior for Brownian motion and thermophoresis parameter. Near the lower half of the plate, velocity increases for the slip parameter whereas it decreases for magnetic and Casson parameters.