Influence of water on exhaust emissions on unmodified diesel engine propelled with biodiesel

The present work aims to investigate the effect of water addition to orange peel oil biodiesel (BD100) in a diesel engine to reduce the exhaust emissions. Fuel samples are prepared with different concentrations of water into biodiesel, 95% biodiesel + 5% water (BD95W5) and 90% orange peel oil biodiesel + 10% water (BD90W10). The water is added to biodiesel in presence of surfactant (Span-80). The experimental investigation on diesel engine reveals that the oxides of nitrogen emission and smoke emission are reduced for BD95W5 and BD90W10 compared to BD100 and diesel. In addition, the introduction of water to biodiesel in diesel engine reduces the carbon monoxide and hydrocarbon emissions noticeably.     

Comparison of a new immobilized Fe3+ catalyst with homogeneous Fe3+–H2O2 system for degradation of 2,4‐dinitrophenol

BACKGROUND: Heterogeneous Fenton catalysts have been used to treat various organic pollutants in an aqueous environment. The present study has investigated the degradation of 2,4‐dinitrophenol (2,4‐DNP), a priority pollutant generated by such industries as pharmaceuticals, pesticides, pigments and dyes. Degradation of 2,4‐DNP (100 mg L^?1) was studied using Fe³⁺ loaded on Al₂O₃ as a heterogeneous catalyst in the presence of H₂O₂, and the efficiency compared with the homogeneous Fe³⁺/H₂O₂ based Fenton‐like process. The effect of different parameters for both processes, such as catalyst loading, H₂O₂ concentration, initial solution pH, initial substrate concentration and temperature were investigated and the optimum operating conditions determined. RESULTS: Under optimal operating conditions of the homogeneous system ([Fe³⁺] 125 mg L^?1; [H₂O₂] 250 mg L^?1; pH 3; room temperature), 92.5% degradation was achieved in 35 min for an initial 2,4‐DNP concentration of 100 mg L^?1. In the case of immobilized Fe (Fe³⁺–Al₂O₃ catalyst), degradation improved to 98.7% under the condition 10 wt% [Fe³⁺–Al₂O₃] 1 g L^?1 catalyst loading; [H₂O₂] 250 mg L^?1; pH 3; at room temperature for the same duration. CONCLUSIONS: This study demonstrated the stability and reusability of the prepared heterogeneous catalyst. This process is a viable technique for treatment of aqueous solutions containing contaminants. Copyright © 2012 Society of Chemical Industry     

The physical properties of sulfonated graphene/poly(vinyl alcohol) composites

Composites of poly(vinyl alcohol) (PVA) with sulfonated graphene (SG) show fibrillar, dendritic and rod like structures for SG1, SG3 and SG5 samples, respectively, where the number indicates weight percent of SG. Differential scanning calorimetry shows a new peak in addition to that of PVA arising from the supramolecular organization of the components in SG1 and SG3. Seventeen percent and 36% increases of PVA crystalline thickness and 77% and 79% increases in amorphous overlayer thickness for SG1 and SG3 over PVA are evident from small angle X-ray scattering results but SG5 does not show any change. Atomic force microscopy results of SG suggest aggregation at higher concentration and the composites exhibit composition dependent mechanical properties with the highest increase of stress (177%), strain at break (45%) and toughness (657%) in SG3 over PVA. Young’s modulus increases with increasing SG concentration with a maximum 180% increase in the SG5 sample. The storage modulus of SG3 shows the highest increase (1005%) over PVA. A 10 orders of magnitude increase of dc conductivity over PVA and a 10-fold increase in the dendritic SG3 to that of other composites are observed. SG1 is semiconducting, SG3 shows an electronic memory and SG5 exhibits a rectification property.     

Microstructural Evolution of A356 Al Alloy During Flow Along a Cooling Slope

Cooling slope (CS) has been used in this study to prepare semi-solid slurry of A356 Al alloy, keeping in view of slurry generation on demand for Rheo-pressure die casting process. Understanding the physics of microstructure evolution during cooling slope slurry formation is important to satisfy the need of semi-sold slurry with desired shape, size and morphology of primary Al phase. Mixture of spherical and rosette shaped primary Al phase has been observed in the samples collected during melt flow through the slope as well as in the cast (mould) samples compared to that of dendritic shape, observed in case of conventionally cast A356 alloy. The liquid melt has been poured into the slope at 650?°C temperature and during flow it falls below the liquidus temperature of the said alloy, which facilitates crystallization of ??-Al crystals on the cooling slope wall. Crystal separation due to melt flow is found responsible for nearly spherical morphology of the primary Al phase.     

Semiconductor to Metallic Phase Transition in Nickel Doped Co0.5Ni X Fe(0.5−X) Fe2O4

Co_0.5Ni _X Fe_(0.5?X) Fe₂O₄ of composition (X=0.1 to 0.5) has been prepared by sol gel auto combustion citrate nitrate method. The molar ratio of metal nitrates to citric acid was maintained as 1:3 to obtain the small crystallite size. A systematic study of XRD, impedance, ac conductivity and dielectric studies of the samples were carried out in the present work. A semiconducting to metallic changeover accompanied by the grain boundary effect gradually replaced by grain contribution has been found from the impedance analysis. Confirmation of phase transition is also obtained from ac conductivity and dielectric analysis of activation energy graph where the slope changes from negative to positive. Nickel doped cobalt ferrite exhibits a semiconducting nature up to 513 K for all the compositions and underwent to metallic phase above 513 K. It is attributed to cation distribution between A and B sites as a function of temperature.     

Promising interaction between nanoencapsulated lutein with low molecular weight chitosan: Characterization and bioavailability of lutein in vitro and in vivo

This study aims to develop water-soluble low molecular weight chitosan (LMWC) nanoencapsules with lutein to improve its bioavailability. Lutein-LMWC nanoencapsules were prepared, characterized and bioavailability was studied in vitro and in vivo with lutein in mixed micelles (control). The particle size ranged between 80–600 nm, which was confirmed by Atomic Force Microscope. The interaction between LMWC and lutein in nanocencapsules by ¹H and ¹³C NMR showed the essentiality of water molecules to hold the lutein between LMWC chains of nanoparticle with a reversible weak bond. Bioavailability of lutein (200 μM) in vitro showed that lutein-LMWC nanoencapsules was significantly higher (27.7%) than control. Postprandial lutein level in the plasma (54.5%), liver (53.9%) and eyes (62.8%) of mice fed on nanoencapsulated lutein were higher than the control. LMWC may serve as novel carrier for enhancing the lutein bioavailability and can be suggested as the better dietary compound in food and pharmaceutical applications.     

Analysis,design, and minimum phase selection of high power interleaved DC–DC converter

The primary use of interleaved bidirectional DC–DC converters (IBC) is for high current applications due to the inherent property of ripple cancellation, high redundancy, and improved efficiency. Proper analysis and design are required to improve the power density and reduce the cost of the $N$-phase IBC. Ripple current analysis plays a vital role in choosing the inductor and filter capacitors to minimize the size of an IBC. This paper presents the simple and generalized formulas for the current ripple minimization of $N$-phase IBC. Also, the inductor is designed with two different core materials, namely, Ferrite and Sendust. It is observed that the area product and weight of the magnetics have been reduced by 22% and 23%, respectively, for Sendust core in comparison with the Ferrite core. Furthermore, a discussion regarding the thermal analysis of IGBT modules to select an appropriate heat sink is stated. Moreover, the minimum phase selection has been proposed by considering several constraints such as area product of the core, discrete components size based on ripple analysis, cost of all components, and converter efficiency. The prototype of the selected minimum phase IBC has been developed and tested for a 7.5 kW power level using TMS320F28335.