Augmenting the performance of acrylonitrile–butadiene–styrene plastics for low‐noise dynamic applications

The main objective of this study was to enhance the performance of acrylonitrile–butadiene–styrene (ABS) plastics for dynamic structural applications, including those of automobile relevance. First, ABS was modified by blending with maleic anhydride grafted styrene–ethylene–butadiene–styrene block copolymer (MA‐g‐SEBS) in various proportions. Squeaking noise characteristics were evaluated by measurement of the frictional behavior in an in‐house fabricated friction testing apparatus, and the results are explained on the basis of the change in surface energy upon modification. Detailed dynamic mechanical analyses (strain, frequency, and temperature sweep) revealed significant improvements in the damping characteristics of the modified ABS, especially that modified with 10 wt % MA‐g‐SEBS, without much sacrifice in its mechanical strength. The modulus values predicted with Kerner's model of the blends were well correlated with the morphological changes upon modification. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Electrospun Hybrid Soy Protein/PVA Fibers

Rheological behavior and spinnability of biodegradable materials based on SPI and PVA were studied for the production of electrospun fibers. pH level, processing temperature, and heating time were adjusted to investigate the effects of denaturing of soy protein on the rheology of SPI/PVA solutions. The results show that zero shear viscosity and degree of shear thinning of the SPI solution can be controlled by adjusting pH level and thermal treatment. The continuous production of uniform SPI/PVA fibers was achieved by electrospinning. The presence and amount of soy protein in the electrospun fibers was determined by EMPA and elemental analysis, confirming that the SPI was well incorporated into the PVA and remained in the electrospun fibers.

     

Experimental investigation of Co and Fe-Doped CuO nanostructured electrode material for remarkable electrochemical performance

The current research work presents a facile and cost–effective co-precipitation method to prepare doped (Co & Fe) CuO and undoped CuO nanostructures without usage of any type of surfactant or capping agents. The structural analysis reveals monoclinic crystal structure of synthesized pure CuO and doped-CuO nanostructures. The effect of different morphologies on the performance of supercapacitors has been found in CV (cyclic voltammetry) and GCD (galvanic charge discharge) investigations. The specific capacitances have been obtained 156 (±5) Fg^?1, 168(±5) Fg^?1 and 186 (±5) Fg^?1 for CuO, Co-doped CuO and Fe-doped CuO electrodes, respectively at scan rate of 5 mVs^?1, while it is found to be 114 (±5) Fg^?1, 136 (±5) Fg^?1 and 170 (±5) Fg^?1 for CuO, Co–CuO and Fe–CuO, respectively at 0.5 Ag^-1 as calculated from the GCD. The super capacitive performance of the Fe–CuO nanorods is mainly attributed to the synergism that evolves between CuO and Fe metal ion. The Fe-doped CuO with its nanorods like morphology provides superior specific capacitance value and excellent cyclic stability among all studied nanostructured electrodes. Consequently, it motivates to the use of Fe-doped CuO nanostructures as electrode material in the next generation energy storage devices.     

Annual and Seasonal Variations of Hydrological Processes Under Climate Change Scenarios in Two Sub-Catchments of a Complex Watershed

The Elbow River watershed, located in the rain shadow of the Rocky Mountains in western Canada, is characterized by a complex hydrological regime due to significant differences in climate and geomorphological settings between the west and east sub-catchments. This watershed has experienced several extreme droughts and floods in the recent decades, which might be accentuated with climate change. This study was undertaken to investigate the average annual and seasonal variations of surface and sub-surface hydrological processes in the west and east sub-catchments along with and the entire watershed under five plausible GCM-scenarios up to 2070 using the physically-based, distributed MIKE SHE/MIKE 11 model. Most of the scenarios indicate a reduction in the average annual overland flow, groundwater recharge and baseflow in the east sub-catchment. The pattern of seasonal change generally exhibits a rise in overland flow, baseflow, evapotranspiration, groundwater recharge, and streamflow in winter-spring and a decline in summer-fall. The induced changes in hydrological processes are proportionally more perceptible in the east sub-catchment compared to the west sub-catchment. However, the west sub-catchment governs the watershed behaviour and determines the future changes, over-riding the stronger climate change signal in the east. This investigation indicates that a greater understanding of climate change impacts on the water balance of a watershed with significant differences in sub-regional settings is achieved when capturing the surface and subsurface hydrological process responses of each sub-catchment individually along with the entire watershed. Such information can guide water resources management by providing a more rigorous assessment of the processes involved in the watershed.     

Purification and kinetic characterization of polyphenol oxidase from Barbados cherry (Malpighia glabra L.)

Polyphenol oxidase (PPO) of Barbados cherry was extracted and purified through ammonium sulfate precipitation, gel filtration, and affinity chromatography. The purification factor for PPO was 60% with 8.3% yield. The enzyme was characterized for thermal stability, pH and kinetic parameters. The molecular mass of PPO was approximately the sum of 52 and 38 kDa estimated by SDS–PAGE. The purity was checked by native PAGE, showing a single prominent band. The optimum pH was 7.2. The enzyme had a temperature optimum at 40 °C and was relatively stable at 60 °C, with 55% loss of activity. Sodium diethyl dithiocarbamate (SDDC), l-cysteine and ascorbate significantly inhibited PPO activity. 4-Methyl catechol and catechol were found to be efficient diphenolic substrates for cherry PPO, considering the _Vmax/_Km$V_{\text{max}}/K_{\mathrm{m}}$ ratio. The data obtained in this study may help to understand cherry fruit browning.     

False aneurysms in carotid arteries of cattle and water buffalo during shechita and halal slaughter

It has previously been shown that the cattle brain is supplied with blood via a basi-occipital plexus, in addition to branches from the carotid and basilar arteries. In addition it has been shown during conventional stunning and slaughter that the carotid arteries in cattle can develop false aneurysms at their severed ends and this can curtail exsanguination. This investigation examined whether false aneurysms can occur during religious slaughter, and during bleeding following electrical stunning that simultaneously induced a cardiac arrest. The prevalence of large (>3 cm outer diameter) false aneurysms in cattle carotid arteries was 10% for both shechita and halal slaughter. The prevalence of animals with bilateral false aneurysms (at least 2 cm in one artery and at least 3 cm diameter in the opposite artery) was 7% and 8% for shechita and halal slaughter, respectively. No false aneurysms occurred during bleeding in cattle that were electrically stunned and simultaneously developed a cardiac arrest. The combination of false aneurysms and collateral routes to the brain present a risk of sustained consciousness during religious slaughter in cattle.     

Fuzzy Multiobjective and Linear Programming Based Management Models for Optimal Land-Water-Crop System Planning

In this article, linear programming and fuzzy optimization models are developed for planning and management of available land-water-crop system of Mahanadi-Kathajodi delta in eastern India. The models are used to optimize the economic return, production and labour utilization, and to search the related cropping patterns and intensities with specified land, water, fertilizer and labour availability, and water use pattern constraints. Due to extreme backwardness of the study area, it has been decided to keep all the three objectives of the linear programming models at the same priority level to obtain the compromised solution in a fuzzy environment that incorporates the imprecision in fuzzy goals and fuzzy constraints. These non-structural models facilitate the conjunctive use of available surface water and groundwater resources. A comparative evaluation along with the benefit-cost ratios of the existing and proposed farming systems is also presented.     

Efficient composite bipolar plate reinforced with carbon fiber and graphene for proton exchange membrane fuel cell

The composite bipolar plates are developed using natural graphite, carbon black, and carbon fiber, along with 1% graphene with phenol formaldehyde (resole) resin. The graphene is developed by thermo-chemical exfoliation of natural graphite and characterized by XRD, Raman, FESEM, and AFM analyses. The synthesized graphene is monolayer graphene with a minimum thickness of 1 Å. The bipolar plates are developed using compression molding technique and thoroughly characterized considering stringent benchmarks (US-DOE and Plug Power Inc.) for PEMFC viz., electrical conductivity, flexural strength, deflection at mid-point, and corrosion current density. The composite bipolar plate showed excellent corrosion resistance to the rigorous fuel cell environment. All the required properties are achieved by the developed composite bipolar plate for PEMFC application. The fuel cell is fabricated with the developed bipolar plate and the performance of the fuel cell is studied. The incorporation of graphene has improved the fuel cell performance significantly.