In vivo efficiency of Bacillus sp. isolated from biofloc system on growth, haematological, immunological and antioxidant status of genetically improved farmed tilapia (GIFT)

714-721In aquaculture, Biofloc technology is emerging as one of the successful sustainable technologies to increase production. It is known to possess several immunostimulatory compounds exhibiting possible probiotic effect in culture. Here, we explored the in vivo efficiency of Bacillus infantis (T1), B. subtilis (T2), Exiguobacterium profundum (T3) and B. megaterium (T4) isolated from biofloc systems for improving the growth and immune performance of genetically improved farmed tilapia (GIFT). Animals (10+0.08 g) were stocked at a density of 100 per m-3 in 500 L FRP tanks for 42 days in triplicate. All the four probiotics (OD =1) were mixed with basal diet in treatments and feed without probiotic maintained as control. A significant difference (P 0.05) in weight gain, specific growth rate and FCR were observed between treatments and control with 100% survival. Serum albumin, globulin, protein, total blood count, glucose, myeloperoxidase activity and SOD were significantly different (P B. megaterium and B. subtilis can be the promising probiotic bacteria isolated from biofloc systems exhibiting multiple benefits with improved growth and health of the culture animals

In vivo efficiency of Bacillus sp. isolated from biofloc system on growth, haematological, immunological and antioxidant status of genetically improved farmed tilapia (GIFT)

In aquaculture, Biofloc technology is emerging as one of the successful sustainable technologies to increase production. It is known to possess several immunostimulatory compounds exhibiting possible probiotic effect in culture. Here, we explored the in vivo efficiency of Bacillus infantis (T1), B. subtilis (T2), Exiguobacterium profundum (T3) and B. megaterium (T4) isolated from biofloc systems for improving the growth and immune performance of genetically improved farmed tilapia (GIFT). Animals (10+0.08 g) were stocked at a density of 100 per m-3 in 500 L FRP tanks for 42 days in triplicate. All the four probiotics (OD =1) were mixed with basal diet in treatments and feed without probiotic maintained as control. A significant difference (P <0.05) in weight gain, specific growth rate and FCR were observed between treatments and control with 100% survival. Serum albumin, globulin, protein, total blood count, glucose, myeloperoxidase activity and SOD were significantly different (P <0.05) between treatments and control. T4 and T2 showed better immunological and anti-oxidant ability when compared to other strains. Results from principal component analysis demonstrated that B. megaterium and B. subtilis can be the promising probiotic bacteria isolated from biofloc systems exhibiting multiple benefits with improved growth and health of the culture animals

Effect of nanoclay and nanoscale TiO2 on carbon/glass fibrereinforced polymer composites

Nanofillers dispersion in polymeric matrix has been identified as a novel method to enhance the mechanical properties of Fibre Reinforced Polymer Nanocomposites (FRPNCs). In general, addition of nanofillers in polymeric resin improves the fracture toughness, tensile and other properties of polymer composites. On the other hand, this inclusion significantly reduces the stiffness, strain at rupture and thermal properties. To overcome these limitations, hybrid nanofillers have been introduced in polymer composites. This work aims to investigate the effect of addition of hybrid nanofillers (Nanoclay-TiO _2 ) on mode I interlaminar fracture toughness (G _IC ), tensile as well as flexural characteristics of carbon/glass/epoxy based composites. The pristine epoxy resin was modified with nanoclay and nanoscale TiO _2 nanofillers together with different weight percentages (0.5, 1, 1.5 & 2 wt%) using mechanical stirrer followed by sonication process. The modified epoxy based carbon/glass polymer laminates were fabricated using hand lay-up process. The lay-up sequence considered in this study was (90 °C/90 °G/0 °G) _S , (90 °G/0 °G/90 °C) _S and (90 °G/0 °C/90 °G) _S . The mechanical properties of modified laminates were characterized by DCB test, tensile and three point bending test. The experimental results show that the addition of hybrid nanofillers in epoxy resin increased the mode I interlaminar fracture toughness (G _IC ) by 77% at 1.5 wt%, tensile strength by 31% at 1.5 wt%, and flexural strength by 33% at 2 wt%. Further addition of nanofillers (<2 wt%) decrease the mechanical properties of FRPNCs as a result of matrix embrittlement. The toughening mechanisms such as fibre pull-out, fibre breaking, particles debonding, and crack deflection were identified at the fractured surfaces

Experimental Investigation and Performance Characteristics Study of Electrolyte in Micro Electrochemical Machining

Many advanced machining processes have higher initial investment, maintenance and tooling costs. In these circumstances micro electrochemical machining [µECM] processes meet the requirements with better efficiency and economy. The micro electrochemical machining process parameter such as electrolyte concentration, machine voltage, and pulse on time and duty factor are optimized with considerations of the multiple performance characteristics such as material removal rate (MRR) and overcut. Increase in electrolyte concentration considerably improves MRR but yields a poorer over cut. Increased machine voltage serves to increase both MRR and over cut significantly. Increased pulse on time and duty factor did not have notable impact on MRR and overcut. Less concentration of sodium chloride [NaCl] is sufficient for machining compared with sodium nitrate [NaNO3]. Higher MRR and better over cut are achieved with sodium chloride and moreover it is more economical than sodium nitrate.</jats:p

Reinforcement of Ethylene Vinyl Acetate with Carbon Black/Silica Hybrid Filler Composites

Carbon black and silica have been used as the main reinforcing fillers that increase the usefulness of rubbers. In this work the effect of carbon black (high abrasion furnace)/silica hybrid fillers on the mechanical properties, crosslink density and morphological behaviour of ethylene vinyl acetate (EVA) was investigated. EVA reinforced with 0/50, 10/40, 20/30, 30/20, 40/10 and 50/0 phr of carbon black (CB)/silica hybrid filler. The total hybrid filler is kept constant at 50 phr (parts per hundred rubbers) and six different compounds were prepared. EVA, CB and silica followed by compounding on a two roll mill and molding at 180°C and 20 megapascal (MPa) pressure. The mechanical properties such as tensile &amp; tear strength, elongation at break and 100% modulus have been measured at 23°C on universal testing machine. Abrasion resistance, hardness and rebound resilience are studied using DIN abrader, Shore A durometer and vertical rebound resilience respectively. The tensile strength, modulus, tear strength, abrasion resistance, hardness and crosslink density increased with the CB filler content in hybrid filler, reached the maximum value at 50 phr of high abrasion furnace carbon black. Morphological properties of composites were evaluated by scanning electron microscopy analysis.</jats:p

Surface Reinforcement on Aluminium Matrix by Hybrid Nanocomposites via FSP: A Review

Aluminium hybrid composites are identified as new generation of metal matrix composites for its good strength to weight ratio and good corrosion resistance properties. However their mechanical properties and tribological properties are still lower than that of commonly applied materials. Hence it is necessary to improve the surface qualities of aluminium matrix and makes it suitable for engineering applications. Friction stir processing (FSP) is an emerging technique which can be used to make surface composites. While FSP of different alloys has been considerably reviewed, surface reinforcement by hybrid nanocomposites on aluminium matrix have not been wholesomely reviewed. The present review offers a comprehensive understanding of friction stir processed aluminium matrix hybrid nanocomposites. The available literature provide the details about the effect of process parameters, reinforcement particles, microstructural evolution during the fabrication of aluminium matrix hybrid nanosurface composites. Few research gaps in fabrication of aluminium matrix surface composites has been revealed in this review such as micro alloying with low melting point metals, defect free composites and interrelationship between process parameters.</jats:p

Effect of nanoclay and nanoscale TiO₂ on carbon/glass fibrereinforced polymer composites

Abstract Nanofillers dispersion in polymeric matrix has been identified as a novel method to enhance the mechanical properties of Fibre Reinforced Polymer Nanocomposites (FRPNCs). In general, addition of nanofillers in polymeric resin improves the fracture toughness, tensile and other properties of polymer composites. On the other hand, this inclusion significantly reduces the stiffness, strain at rupture and thermal properties. To overcome these limitations, hybrid nanofillers have been introduced in polymer composites. This work aims to investigate the effect of addition of hybrid nanofillers (Nanoclay-TiO2) on mode I interlaminar fracture toughness (GIC), tensile as well as flexural characteristics of carbon/glass/epoxy based composites. The pristine epoxy resin was modified with nanoclay and nanoscale TiO2 nanofillers together with different weight percentages (0.5, 1, 1.5 &amp; 2 wt%) using mechanical stirrer followed by sonication process. The modified epoxy based carbon/glass polymer laminates were fabricated using hand lay-up process. The lay-up sequence considered in this study was (90 °C/90 °G/0 °G)S, (90 °G/0 °G/90 °C)S and (90 °G/0 °C/90 °G)S. The mechanical properties of modified laminates were characterized by DCB test, tensile and three point bending test. The experimental results show that the addition of hybrid nanofillers in epoxy resin increased the mode I interlaminar fracture toughness (GIC) by 77% at 1.5 wt%, tensile strength by 31% at 1.5 wt%, and flexural strength by 33% at 2 wt%. Further addition of nanofillers (&lt;2 wt%) decrease the mechanical properties of FRPNCs as a result of matrix embrittlement. The toughening mechanisms such as fibre pull-out, fibre breaking, particles debonding, and crack deflection were identified at the fractured surfaces.</jats:p

Optimization of Plate Heat Exchanger by Using Response Surface Method

This study deals the purpose of optimal values of the design constraints in a Plate Heat Exchanger by using Response Surface Method (RSM). The special effects of design constraints such as Reynolds number, flow velocity and pressure drop are examined. In the Reference Surface Method experimental design method, Nusselt number and friction factor are considered as performance parameters. The analysis of Reference Surface Method conducted with an optimization process to reach minimum pressure drop (friction factor) and maximum heat transfer (Nusselt number) for the designed Plate heat exchanger. Experimental results authorized the correctness of the planned method. Design expert 7.0 has been used for optimization process. Optimal values are selected from highest desirability value which is 0.80161 and design constrains has been optimized as 1600(Reynolds number), 0.04 m2 (Core area), 1.24 m (Core length).</jats:p