Comparison of Industrial Scale Ethanol Production from a Palmyrah‐Based Carbon Source by Commercial Yeast and a Mixed Culture from Palmyrah Toddy

Palmyrah (Borassus flabellifer) based products were used as an alternative carbon source for industrial scale ethanol production. The fermentation medium was enriched with spent wash obtained from a distillation column. The performance of a commercially available baker's yeast in the media was compared with a ‘palmyrah toddy mixed culture’ where the organisms were obtained from the sedimentation of palmyrah toddy. In a laboratory scale study, the ethanol produced from a palmyrah fruit pulp extract, diluted with distilled water, was 16.5 gL^?1 (36 h) and 13.0 gL^?1 (48 h) with ‘palmyrah toddy mixed culture’ and baker's yeast respectively. The ‘palmyrah toddy mixed culture’ performed better than the baker's yeast with palmyrah fruit pulp extract, diluted either with distilled water or spent wash. Among the different palmyrah based carbon sources, both cultures preferred molasses diluted with spent wash and both performed best in the medium containing the spent wash supplemented with sucrose. In a 5,000 L industrial scale fermentation of 20° Brix molasses supplemented with 10 gL^?1 ammonium sulphate, 72 gL^?1 and 65 gL^?1 ethanol was produced by the ‘palmyrah toddy mixed culture’ (72 h) and the baker's yeast (90 h) respectively. As the performance of the ‘palmyrah toddy mixed culture’ was better than that of the baker's yeast, the former was selected for the industrial scale studies of molasses fermentation media diluted with spent wash. In these studies the temperature reached 42°C by 36 h and resultant cell death was observed. However ethanol production was higher and more rapid in the molasses diluted with spent wash, rather than in the molasses diluted with tap water and supplemented with (NH₄)₂SO₄. Cell recycle operation obviated the interruption in fermentation caused by temperature induced cell death and increased rates and efficiency of ethanol production were observed.     

Effect of microwave treatment on the cooking and macronutrient qualities of pulses

The effect of microwave treatment to reduce the cooking times of five pulses, namely red lentil, chickpea, pigeon pea, mung bean, and pinto bean, were determined in this study. Pulses from 10 to 18% moisture contents were treated using 400 to 600 W microwaves for 14 to 56 s. The cooking times of microwave-treated pulses were significantly lower than that of the control samples. The lowest cooking time was observed for 18% moisture content chickpea and pigeon pea treated with 600 W for 56 s. The Fourier transform mid-infrared spectra in both lipids and fingerprint regions showed the macronutrients differences among the five pulses. Major changes were observed in the amide I region of microwave treated pulses. This effect of microwave treatment was higher in red lentil, chickpea, and mung bean than in pigeon pea and pinto bean at 10% moisture content. At 18% moisture content, the change of β-sheets to aggregates was observed in all pulses due to microwave treatment.     

Hydrothermally synthesized ZnO and Z-rGO nanorods: Effect of post-annealing temperature and rGO incorporation on hydrogen sensing

Journal of Materials Science: Materials in Electronics - In this work, hydrogen-sensing characteristics of zinc oxide nanorods and reduced graphene oxide-incorporated zinc oxide nanorods are...     

Manganese–Schiff base complex immobilized silica materials for electrocatalytic oxygen reduction

Curtailment of platinum catalysts loading in fuel cell is a recent central issue. As substitutes, these days several organic metal chelate compounds having featured moieties of M–N₄ or M–N₂O₂ (M = transition metal ion) are being used as cathode catalysts in fuel cells. Here, in this study, we report in detail the electrocatalytic activity of manganese–Schiff base complexes for oxygen reduction reaction in 0·05 M HClO₄ at room temperature. Actually, [Mn(salen)]⁺: [N,N′-bis(salicylaldehyde) ethylenediimino manganese(III)]⁺ and [Mn(salophen)]⁺: [N,N′-bis(salicylaldehyde)-1,2-phenylenediimino manganese(III)]⁺ were introduced into/onto the MCM-41 type silica spheres and used for the electrocatalytic reduction of oxygen. Synthesized materials were characterized by UV–Vis, FT–IR and electrochemical techniques. Significant low overpotential for oxygen reduction in 0·05 M HClO₄ on [Mn(salen)]⁺- and [Mn(salophen)]⁺-incorporated silica-modified glassy carbon electrodes was observed.     

Fabrication of Thick Germanium-on-Insulator (GeOI) Substrates

Fabrication of germanium-on-insulator (GeOI) substrates with a 160-nm-thick Ge layer is reported. Such thick GeOI substrates were fabricated by thermal intermixing and subsequent condensation of epitaxially grown high-Ge- content SiGe on Si-on-insulator (SOI) substrates. Transmission electron microscopy revealed that the GeOI layer was single crystalline. The high-resolution rocking curve and reciprocal lattice map obtained from X-ray diffraction measurements showed a relaxed GeOI. This was further confirmed by micro-Raman measurements, where the Ge-Ge optical phonon peak shift represented a nearly strain-free Ge layer. Using this methodology, GeOI substrates with Ge layers 120–160 nm thick have been fabricated with thickness variations of less than 4 nm across 200 mm wafers.     

Large- and very-large-scale motions in channel and boundary-layer flows

Large-scale motions (LSMs; having wavelengths up to 2-3 pipe radii) and very-LSMs (having wavelengths more than 3 pipe radii) have been shown to carry more than half of the kinetic energy and Reynolds shear stress in a fully developed pipe flow. Studies using essentially the same methods of measurement and analysis have been extended to channel and zero-pressure-gradient boundary-layer flows to determine whether large structures appear in these canonical wall flows and how their properties compare with that of the pipe flow. The very large scales, especially those of the boundary layer, are shorter than the corresponding scales in the pipe flow, but otherwise share a common behaviour, suggesting that they arise from similar mechanism(s) aside from the modifying influences of the outer geometries. Spectra of the net force due to the Reynolds shear stress in the channel and boundary layer flows are similar to those in the pipe flow. They show that the very-large-scale and main turbulent motions act to decelerate the flow in the region above the maximum of the Reynolds shear stress.     

Synthesis,characterization, and ion exchange voltammetry study on 2‐acrylamido‐2‐methylpropane sulphonic acid and N‐(hydroxymethyl) acrylamide‐based copolymer

A random copolymer of 2‐acrylamido‐2‐methylpropane sulfonic acid (AMPS) and N‐hydroxymethyl acrylamide (NHMA) was prepared by solution polymerization using ceric ammonium nitrate as an initiator. A grade of poly(AMPS)‐co‐poly(NHMA) (PAMPS‐co‐PNHMA) random copolymer was synthesized with AMPS and NHMA. The homopolymerization of AMPS and NHMA was also carried out by the same way as that of random copolymer. PAMPS‐co‐PNHMA and homopolymers of AMPS and NHMA were characterized by FTIR, rheology, FT‐NMR, scanning electron microscope, thermal analysis, and X‐ray diffaractometry. Cyclic voltammetry is used to explain the ion exchange properties of PAMPS‐co‐PNHMA and its possible application in the trace analysis. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Mechanical properties characterisation of dissimilar joint of high-temperature materials using Thermo-Calc Classic (TCC) diagram analysis

Weldments were fabricated between Incoloy 800HT and P91 steel using ERNiCr-3, and ER505 filler materials by GTAW process. The ERNiCr-3 weld has to interface columnar and equiaxed dendrites whereas the ER505 weld has cellular dendrites. The ER505 weld / P91 steel base interface shows δ ferrite. Unmixed zone (UMZ) on Incoloy 800HT side and Type I and Type II zones were observed on P91 steel side of weldments. It was observed that with an increase in heat input, there was an increase in tensile strength of ERNiCr-3 weldments whereas there was a decrease in tensile strength of ER505 weldments. The impact energy of ERNiCr-3 welds was 96 Joules whereas ER505 welds had the impact energy of 178 Joules. Based on microstructure and mechanical properties, ER505 was found to be the ideal filler for joining of Incoloy 800HT to P91 steel than ERNiCr-3 filler.     

Integrated high-/spl kappa/ (/spl kappa/ /spl sim/19) MIM capacitor with Cu/low-/spl kappa/ interconnects for RF application

We demonstrate a high-performance metal-high /spl kappa/ insulator-metal (MIM) capacitor integrated with a Cu/low-/spl kappa/ backend interconnection. The high-/spl kappa/ used was laminated HfO/sub 2/-Al/sub 2/O/sub 3/ with effective /spl kappa/ /spl sim/19 and the low-/spl kappa/ dielectric used was Black Diamond with /spl kappa/ /spl sim/2.9. The MIM capacitor (/spl sim/13.4 fF//spl mu/m/sup 2/) achieved a Q-factor /spl sim/53 at 2.5 GHz and 11.7 pF. The resonant frequency f/sub r/ was 21% higher in comparison to an equivalently integrated Si/sub 3/N/sub 4/-MIM capacitor (/spl sim/0.93 fF//spl mu/m/sup 2/) having similar capacitance 11.2 pF. The impacts of high-/spl kappa/ insulator and low-/spl kappa/ interconnect dielectric on the mechanism for resonant frequency improvement are distinguished using equivalent circuit analysis. This letter suggests that integrated high-/spl kappa/ MIM could be a promising alternative capacitor structure for future high-performance RF applications.