Composites from compounding wood fibers with recycled high density polyethylene

The development of composites consisting of wood fibers and recycled plastics offers not only an opportunity to utilize an abundant natural resource but also a means to alleviate the serious plastics disposal problem. In this work, aspen fibers are incorporated into recycled high density polyethylene with a co-rotating inter-meshing twin-screw extruder to study processing-property relationships. Tensile, impact, and flexural strengths are measured as functions of fiber concentration. The effects of fiber pretreatment, screw configuration, and compounding temperature on the properties of composites are discussed.     

Characterization of Zn doped MgTiO<Subscript>3</Subscript> ceramics: an approach for RF capacitor applications

In the present study the effect of Zn substitution on densification, microstructure, microwave and broad band dielectric properties of MgTiO₃ ceramics were investigated. The (Mg_1?x Zn _x )TiO₃ (x?=?0.01–0.07) ceramics have been prepared by the conventional solid-state reaction method. The sintering conditions were optimized to obtain the best dielectric properties with maximum relative densities. The microwave dielectric properties are heavily influenced by the amount of x concentration. The optimum dielectric properties of ε _r ~ 17.34, Q?×?f _o ~ 274 THz, τ _f ~ -40.3 ppm/^oC is obtained for (Mg_0.95Zn_0.05)TiO₃ ceramics sintered at 1275?°C. The broad band dielectric properties of (Mg_0.95Zn_0.05)TiO₃ ceramics were measured in the frequency range of 1–100 MHz, and temperature range of 133–483 K. Interestingly, the broad band dielectric properties show relaxation behaviour with frequency. The higher temperature dielectric spectrum of (Mg_0.95Zn_0.05)TiO₃ (MZT) ceramics displayed a distinct dispersion, which is shifting towards a lower frequency side. The observed dielectric relaxation behavior is analyzed using Cole–Cole plot. Furthermore, voltage dependent capacitance behavior at different frequencies is studied for the MZT sample, and it’s interesting to note that the capacitance is stable with the variation in voltage. The electrical conductivity study is carried out as a function of frequency and temperature for MZT sample and the activation energy is calculated by using Arrhenius equation, which is found to be 0.07 eV at 10 MHz. The obtained dielectric response of MZT ceramics are suitable for dielectric resonator and type-1 RF capacitor applications.     

The use of Koroch seed oil methyl ester blends as fuel in a diesel engine

An experimental investigation was carried out on a small direct injection (DI) diesel engine, fuelling the engine with 10% (B10), 20% (B20), 30% (B30) and 40% (B40) blending of Koroch seed oil methyl ester (KSOME) with diesel. The performance and combustion characteristics of the engine at various loads are compared and analyzed. The results showed higher brake specific fuel consumption (BSFC) and lower brake thermal efficiency (BTE) for the KSOME blends. The engine indicated power (IP) was more for the blends up to B30, but found to be reduced for the blend B40 when compared to that of diesel. The engine combustion parameters such as pressure crank angle diagram, peak pressure, time of occurrence of peak pressure, net heat-release rate, cumulative heat release, ignition delay and combustion duration were computed. The KSOME blends exhibited similar combustion trend with diesel. However, the blends showed an early start of combustion with shorter ignition delay period. The study reveals the suitability of KSOME blends up to B30 as fuel for a diesel engine mainly used in generating sets and the agricultural applications in India without any significant drop in engine performance.     

Thermocapillary thin film flow upon a porous heated stretchable cylinder

Earlier research work related to the unsteady flow of thin liquid film on a heated stretching cylinder has considered the boundary-layer approximation under the assumption that the film thickness is thick. In this article, we have considered the full set of Navier–Stokes equations to study the unsteady film development over a porous heated stretching cylinder with the assumption that film height either coincides or lies within the boundary-layer thickness. The effects of magnetic field, suction/injection, and cooling or heating of the cylinder have been considered for investigation. The governing set of coupled nonlinear partial differential equations is solved numerically by the implicit finite difference scheme (Crank–Nicolson). It was found that the film thinning rate diminishes with rising values of the porosity parameter and Hartmann number. It is also noted that the film thickness is enhanced for injection whereas opposite results are observed for suction through the porous cylinder. The thermocapillary effect showed that the thinning rate of the liquid film decreases or increases according to the surface of the cylinder being heated or cooled. It is observed that continuously increasing the stretching speed of the cylinder produces faster thinning of the liquid film. The temperature of the liquid film is the maximum at the surface of the cylinder and it decreases toward the free surface when the cylinder is heated. But the opposite phenomenon occurs when the cylinder is cooled.     

3,5‐Dimethylpyrazolium Fluorochromate(VI)‐Catalysed Oxidation of Organic Substrates by Hydrogen Peroxide under Solvent‐Free Conditions

3,5‐Dimethylpyrazolium fluorochromate (VI), C₅H₈N₂H[CrO₃F], DmpzHFC , serves as an efficient catalyst for oxidation of primary, secondary and allylic alcohols to the corresponding carbonyl compounds using H₂O₂ at room temperature under solvent‐free conditions. Oxidation of methyl phenyl sulfides and triphenylphosphine were also carried out successfully.     

A cycle simulation model for predicting the performance of a diesel engine fuelled by diesel and biodiesel blends

Among the alternative fuels, biodiesel and its blends are considered suitable and the most promising fuel for diesel engine. The properties of biodiesel are found similar to that of diesel. Many researchers have experimentally evaluated the performance characteristics of conventional diesel engines fuelled by biodiesel and its blends. However, experiments require enormous effort, money and time. Hence, a cycle simulation model incorporating a thermodynamic based single zone combustion model is developed to predict the performance of diesel engine. The effect of engine speed and compression ratio on brake power and brake thermal efficiency is analysed through the model. The fuel considered for the analysis are diesel, 20%, 40%, 60% blending of diesel and biodiesel derived from Karanja oil (Pongamia Glabra). The model predicts similar performance with diesel, 20% and 40% blending. However, with 60% blending, it reveals better performance in terms of brake power and brake thermal efficiency.     

Lignin‐polystyrene composite foams through high internal phase emulsion polymerization

The composites made‐up from renewable fillers and polymer matrix have drawn great attention due to the renewable nature, improved thermal and mechanical properties, environmental issues and most importantly to reduce dependency on fossil fuel resources. In this work, kraft lignin in its modified form (butylated lignin) was used to make composites with polystyrene successfully through bulk polymerization and high internal phase emulsion (HIPE) polymerization. The kraft lignin was first modified to butyrated lignin by esterification using 1‐Methylimidazole as a catalyst in order to increase the compatibility as fillers with both monomer and polymer, which was further studied and verified through Hansen solubility parameter model. The thermal, mechanical, and structural properties of the lignin/polymer composites were systematically investigated. The incorporation of lignin in the composites could increase the modulus significantly and almost double (1,391 MPa) at 15 wt% of lignin loading as compared with bare composites. Excellent porous structure and mechanical properties are maintained with the lignin content as high as 10 wt% of the total foam mass. POLYM. ENG. SCI., 59:964–972, 2019. © 2018 Society of Plastics Engineers     

Correction to: A new analytical model for switching time of a perforated MEMS switch

Microsystem Technologies - Unfortunately, a co-author’s name was not listed in the original publication. The missing author name and affiliation is given below:     

Utilizing the Oxygen Carrier Property of Cerium Iron Oxide for the Low-Temperature Synthesis of 1,3-butadiene from 1-butene

Catalysis Letters - Low-temperature oxidative dehydrogenation (ODH) of 1-butene to 1,3-butadiene is one of the challenging reactions in the polymer industry. Towards this a highly dispersed cerium...