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Friction stir welding (FSW) is a solid-state joining process producing high-quality welds with lower residual stresses and improved mechanical properties. Underwater FSW is a variant of FSW process which controls heat conduction and dissipation along the weld line improving the joint properties. The feasibility of underwater friction stir welding of AA 5052 H32 aluminum alloy to improve the joint performance than normal friction stir welding is addressed in this paper. The effects of tool rotational speed and welding speed on ultimate tensile strength by underwater and normal friction stir welding were analyzed and compared. It was observed that the tensile strength of underwater welded joints was higher than normal FSW joints except at 500 rpm. Maximum tensile strength of 208.9 MPa was obtained by underwater friction stir welding at 700 rpm tool rotational speed and welding speed of 65 mm/min. The optimum process parameters for achieving maximum tensile strength by normal FSW were compared with underwater FSW. The result showed that the ultimate tensile strength obtained by underwater FSW was about 2% greater than that of the normal FSW process. The joints with maximum tensile strength during underwater and normal welding fractured at the retreating side of the welded joint. Microstructural examination revealed that heat-affected region was not found in underwater welding. Microhardness was decreased slightly towards the stir zone. Fractography observation revealed that the welded joints exhibiting higher joint efficiency failed under ductile mode. [ABSTRACT FROM AUTHOR]

A facile approach for the synthesis of La2CuO4, CeO2, La2CuO4/CeO2 and novel La2CuO4/CeO2/rGO hybrid nanocomposites were demonstrated via solvothermal assisted homogeneous precipitation method. The surface morphology, phase and crystal structure of the synthesized materials were characterized by field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX), High resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD). The photocatalytic performance to oxidize a target pollutant RB160 dye and inactivation of bacteria in aqueous solution was investigated under the illumination of visible light. Absorption range and band gap energy were investigated by UV-vis diffuse reflectance spectroscopy (UV-vis DRS). The combination of rGO with La2CuO4/CeO2 nanocomposites leads to a better photocatalytic activity than other bare synthesized materials. Typically, 10 mg/l of RB160 could be almost completely oxidized in 150 min and 0.01 g/l of La2CuO4/CeO2/rGO, exhibiting a promising application of the photocatalyst in the degradation of aqueous organic pollutants. The efficiency of RB160 decomposition increased with increasing pH (5-11) and catalyst dosage (0.01-0.03 g/l), but it gets decreased with increasing initial RB160 concentration (10-30 mg/l) and from that the optimum condition for the better photocatalytic performance was identified. Furthermore, the antibacterial activity of La2CuO4/CeO2/rGO hybrid nanocomposite was also investigated by using two different bacteria in typical aqueous medium and the results were showed highly efficient visible light driven photocatalytic antibacterial activity. The enhanced photocatalytic and antibacterial activity of La2CuO4/CeO2/rGO is promising for the further application of visible light driven photocatalyst in polluted water treatment. [ABSTRACT FROM AUTHOR]

Geometry of tool pin profiles plays a significant role in deciding the quality of weld in friction stir welding process. In the present study, the effect of tool pin profile on the mechanical and metallographic characteristics of the friction stir welding on AA 5052- H32 aluminium plates was investigated. Various geometry of tool pin profile such as cylindrical tapered, hexagon tapered, pentagon tapered, square tapered, and, triangular tapered, having a constant circumscribed circle diameter were used for the study and the results are compared. Other weld parameters such as tool tilt angle, rotational speed, welding speed were kept constant based on the response from several trial runs conducted. Mechanical test results reveal that highest tensile strength and hardness value were obtained with tapered square tool pin profile and the joint failed under ductile mode. Fine equiaxed grain structure was observed at the stir zone with tapered square tool pin profile. EDS result on plate welded by tapered square tool pin profile shows that there is no β-phase (Mg2Al3) precipitate at the stir zone and therefore no sensitization of segregation as the result of FSW, thereby resists localized intergranular corrosion at the weld site. [ABSTRACT FROM AUTHOR]

Abstract: Although cassava (Manihot esculenta Crantz) is a potential bioethanol crop, high operational costs resulted in a negative energy balance in the earlier processes. The present study aimed at optimizing the bioethanol production from cassava starch using new enzymes like Spezyme® Xtra and Stargen™ 001. The liquefying enzyme Spezyme was optimally active at 90 °C and pH 5.5 on a 10% (w/v) starch slurry at levels of 20.0 mg (280 Amylase Activity Units) for 30 min. Stargen levels of 100 mg (45.6 Granular Starch Hydrolyzing Units) were sufficient to almost completely hydrolyze 10% (w/v) starch at room temperature (30 ± 1 °C). Ethanol yield and fermentation efficiency were very high (533 g/kg and 94.0% respectively) in the Stargen + yeast process with 10% (w/v) starch for 48 h. Raising Spezyme and Stargen levels to 560 AAU and 91.2 GSHU respectively for a two step loading [initial 20% (w/v) followed by 20% starch after Spezyme thinning]/initial higher loading of starch (40% w/v) resulted in poor fermentation efficiency. Upscaling experiments using 1.0 kg starch showed that Stargen to starch ratio of 1:100 (w/w) could yield around 558 g ethanol/kg starch, with a high fermentation efficiency of 98.4%. The study showed that Spezyme level beyond 20.0 mg for a 10% (w/v) starch slurry was not critical for optimizing bioethanol yield from cassava starch, although an initial thinning of starch for 30 min by Spezyme facilitated rapid saccharification–fermentation by Stargen + yeast system. The specific advantage of the new process was that the reaction could be completed within 48.5 h at 30 ± 1 °C. [ABSTRACT FROM AUTHOR]

In the present study, we synthesized g-C 3 N 4 /BiOBr/CdS photocatalyst by hydrothermal assisted precipitation method. The structure and morphology of the prepared photocatalyst were characterized and also the optical properties of the photocatalyst were investigated as well. The visible-light-driven g-C 3 N 4 /BiOBr/CdS photocatalyst exhibited enhanced photocatalytic performance towards TC degradation. In particular, the g-C 3 N 4 /BiOBr/CdS photocatalyst showed the highest photocatalytic degradation rate performance, which was superior to that observed 8.95 times for g-C 3 N 4 , 3.11 times for BiOBr and 3.18 times for BiOBr/CdS composite, and it also displayed good stability during recycling experiments. The enhanced photocatalytic efficiency was mainly attributed to rapid charge transfer at the g-C 3 N 4 /BiOBr/CdS interfaces, which promotes the separation efficiency of photogenerated charge carriers and improves optical absorption. Furthermore, a possible photocatalytic mechanism of the g-C 3 N 4 /BiOBr/CdS photocatalyst is proposed based on the experimental studies. The present research work would provide new insight into the design and fabrication of visible-light-driven photocatalyst for energy storage and environmental protection applications. Unlabelled Image • g-C 3 N 4 /BiOBr/CdS photocatalysts were successfully synthesized. • The visible-light driven g-C 3 N 4 /BiOBr/CdS photocatalysts exhibit enhanced TC degradation. • Rapid charge transfer at the dual interface contributed to high photocatalytic activity. • g-C 3 N 4 /BiOBr/CdS photocatalyst displayed high photostability during recycling experiment. • A possible photocatalytic mechanism was investigated. [ABSTRACT FROM AUTHOR]

This research demonstrates the synthesis of phase pure Fe 2 O 3 nanoclusters using Caralluma Fimbriata and Achyranthes Aspera as reducing and stabilizing agents. The structure and physicochemical property of the nanoparticles are characterized by X-Ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Ultraviolet Diffuse Reflectance Spectroscopy (UV-DRS), Field Emission Scanning Electron Microscopy (FESEM) and High-Resolution Transmission Electron Microscopy (HRTEM) analysis. The HRTEM results reveals that the particle size of C. Fimbriata and A. Aspera treated Fe 2 O 3 nanoparticles were found to be ∼25 nm and ∼22 nm, respectively. The photocatalytic degradation and reusable of the green treated Fe 2 O 3 Nanoparticles were performed by the photodegradation of Methylene Blue (MB) dye solution under solar light irradiation. In addition, green synthesized Fe 2 O 3 nanoparticles assayed against gram-negative bacteria Escherichia coli (E.coli). [ABSTRACT FROM AUTHOR]

In this paper, grey relational analysis combined with Taguchi method has been used to evaluate the weld ability of AZ31B magnesium alloy by FSW process. The L9 Taguchi design considering an orthogonal array consists of 3 factors and 3 levels was used for experimentation. The rotational speed of tool, transverse speed and angle of tilt of the tool are selected as welding parameters. The welding parameters influence on responses namely Ultimate Tensile Strength (UTS) and hardness has been analyzed using ANOVA. The analysis results showed transverse speed as the predominant welding parameter affecting tensile strength, hardness, and weld quality. Confirmation test results showed that grey relational analysis along with Taguchi method yielded better results in the optimization of welding parameters in FSW of AZ31B magnesium alloy. [ABSTRACT FROM AUTHOR]

The synthesis of bioactive CuO/C nano composite using sucrose as a capping agent is achieved through simple green approach via Response Surface Methodology. The synthesis process was done in a green environment which prevents aggregation of sucrose and promotes nanoparticles formation. The innovative approach produces sucrose as a carbon source mediated copper oxide nanocomposites (CuO/C nanocomposite) with the particle size of 50 nm. Additionally, the produced CuO/C nanocomposite were characterized using microscopic techniques like SEM, TEM and spectroscopic techniques like UV–vis and X-ray diffraction. The antifungal activities of CuO/C nanocomposite were tested against Aspergillus niger and Aspergillus flavus species. At 1000 ppm of CuO/C nanocomposite, it showed 70% restraint on A. flavus and 90% hindrance on A. niger. The fungal inhibition mechanism of bioactive CuO/C nanocomposite was discussed in this research article. The particular high antifungal performance of CuO/C nanocomposite was found against Aspergillus niger while compare to Aspergillus flavus fungal strain. • The CuO/C nanocomposite was synthesized by using sucrose as a carbon source. • The formation of CuO/C nanocomposite was monitored by UV–Vis spectral analysis. • The antifungal activity of CuO/C were tested against A. niger and A. flavus species. • CuO/C nanocomposite showed higher antifungal activity against A. niger while compare to A. flavus fungal strain. [ABSTRACT FROM AUTHOR]

Dye‐sensitized solar cells (DSSCs) have considerable attention to the academic and industrial community. Because, it makes solar energy efficient and cost effective to harness. DSSCs is one of the important roles in the design of sensitizers with sustainable and environmentally‐friendly materials. In the present work, a series of D‐π‐A architecture with tetrahydroquinoline based organic dye sensitizer were designed and modifying π‐linker (SP1‐SP9) for the potential use in DSSCs application by DFT and TD‐DFT calculations. There are different functional groups were analyzed through a proper methodology for calculations and comparison with C1‐1 dye. From these functionals, the TD‐ωB97XD method was reasonably capable of predicting the absorption spectra of the molecules. Moreover, SP1‐SP9 dye molecules were systematically analyzed by using various parameters such as the energy gap (Eg), absorption spectra, light harvesting efficiency (LHE), open circuit photovoltage (eVOC), dipole moment (μnormal), free energy change for electron injection (ΔGinject), regeneration (ΔGreg) and chemical hardness (η). As a whole, all the designed dyes, especially SP6, SP7, SP8 dyes are showed smallerEg , red‐shift absorption spectra, largest μnormal , negative ΔGinject and fastest ΔGreg values, compared to C1‐1. Based on our result shows that SP6, SP7 and SP8 dye molecules are the best candidates to provide superior performances in the DSSCs application. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The effect of rGO based WO 3 and Fe 2 O 3 ternary nanocomposite was extensively investigated. • rGO in ternary nanocomposite could reduce the recombination of electron hole pairs. • The as-prepared ternary nanocomposites showed enhanced photocatalytic activity, metal ion removal and antibacterial activity. • Mechanism of enhanced photocatalytic activity was proposed and discussed. Abstract The combination of two or more metal oxides onto graphene sheets with even distribution is projected to enhanced charge transfer properties in photocatalytic applications. We report, tungsten oxide (WO 3) with iron oxide (Fe 2 O 3) nanoparticles grown on graphene sheets via a facile economical one pot hydrothermal method and consequently characterized by standard analytical techniques. Synthesized Fe 2 O 3 with WO 3 nanoparticles were well ornamented on surface of the graphene sheets which have a significant charge transfer properties. The resulting hybrid WO 3 -Fe 2 O 3 -rGO (WFG) nanocomposites showed enhanced photocatalytic, heavy metal removal and antibacterial activities. The superior photocatalytic removal efficiencies were observed for the removal of rhodamine B (∼94%) and methylene blue dyes (∼98%) under solar light irradiation. The antibacterial activity of WFG nanocomposites were performed against Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus) as models for Gram-negative and Gram-positive bacteria. The outcome of the results have an intellectual effect on the use of WFG nanocomposites to address the upcoming energy and environment issues. [ABSTRACT FROM AUTHOR]

The present study aims to assess the genetic and multivariate component analysis of processing traits, yield traits, weevil resistance and other tuber traits in sweet potatoes based on the evaluation of 12 genotypes, including checks for yield and processing. Significant variability for tuber physical, processing and vine traits was observed. Nearly 75% of the genotypes had dry matter content (>30%), 50% had starch content (>20%), and none was resistant to sweet potato weevils. High genotypic and phenotypic variation, heritability and genetic advance were observed for tuber yield, tuber girth, total sugar and weight. Among the 13 phenotypic traits used in the present study, multivariate analysis identified only eight, contributing to 83.67% of the variation. UPGMA clustering yielded two major clusters and five sub-clusters. S27, Palakkad local, Trivandrum local, Sree Arun, S346, S27, Indira Madhur, EC 321693 and S444 were found suitable for processing. These genotypes can serve as breeding material for developing high-yielding varieties, thereby promoting the industrial utilization of sweet potatoes. [ABSTRACT FROM AUTHOR]

Owing to increase in cost and low availability of Li source causes the high rate of the energy storage devices. By focusing on these issues, the cost effective and high performed electrode is needed for energy storage application. Na based electrodes can replace the Li ion batteries because of the availability of Na is higher than the Li. The cost of the energy storage devices can be reduced by using Na instead of Li. Many other electrodes are reported based on Na ion batteries. Since in this present work we prepared O3–NaFeO 2 (NIO) high performance electrode prepared by two step hydrothermal assisted solid-state method. But the battery performance of NaFeO2 is suffers from capacity decay during long term cycling. For these issues naturally derived sucrose from the sugarcane is prepared which increase the electrochemical performance of Ac carbon coated NaFeO 2 (AC Coated NIO). The AC Coated NIO electrode delivers the capacity of about 131 mAh g−1 at 80 mA g−1. The retention capacity of material is about 92% after 100 cycles. Such electrochemical action of the current electrode can show the way to cost effective and highly performed Na ion electrode development for Energy storage devices. [ABSTRACT FROM AUTHOR]

The SnO 2 and SnO 2 /rGO nanostructures were successfully synthesized using the facile hydrothermal synthesis technique. The prepared nanostructures were well studied using different techniques such as XRD, XPS, UV-DRS, FT-IR, EDX, SEM and HR-TEM analysis. The crystalline nature of SnO 2 and SnO 2 /rGO was confirmed by the XRD technique. The formation of highly pure SnO 2 and SnO 2 /rGO nanostructures was confirmed by EDX analysis. The morphological results show the good agglomeration of several spherical nanoparticles. The optical properties were studied through the UV-DRS technique and the bandgap energies of SnO 2 and SnO 2 /rGO are estimated to be 3.12 eV and 2.71 eV, respectively. The photocatalytic degradation percentage in presence of SnO 2 and SnO 2 /rGO against RhB was found to be 96% and 98%, respectively. The degradation of TTC molecules was estimated as 90% and 88% with SnO 2 /rGO and SnO 2 , respectively. The degradation of both RhB and TTC molecules was well suited with the pseudo-first-order kinetics. The results of successive experiments clearly show the enhancement in the photocatalytic properties in the SnO 2 /rGO nanostructures. [Display omitted] • SnO 2 and SnO 2 /rGO were successfully synthesized using hydrothermal technique. • Visible light absorption ability of SnO 2 and SGO is confirmed by UV-DRS analysis. • Photocatalytic activity of SnO 2 and SnO 2 /rGO was studied against Rhodamine B and Tetracycline. • Photocatalytic degradation mechanism is proposed based on optical properties and band edge positions. [ABSTRACT FROM AUTHOR]

The formation of phase pure magnetically separable α-Fe 2 O 3 and α-Fe 2 O 3 /rGO nanostructures were achieved through a simple hydrothermal technique. The properties of synthesized materials were investigated through different analytical techniques. The formation of phase pure FO and FO/rGO nanostructures were confirmed by XRD analysis with crystallite size of about ∼42 nm and ∼65 nm, respectively. The morphological analysis reveals the formation of sphere-like nanoparticles with high agglomeration. The UV-DRS analysis clearly shows the enhanced visible-light activity of FO/rGO nanoparticles. The BET analysis revealed the mesoporous property of FO/rGO nanocomposite. The enhancement in the photoinduced charge transfer process is observed after including rGO nanoparticles with FO. The photocatalytic efficiency of nanomaterials was analyzed using tetracycline and ibuprofen as model organic pollutants under white LED irradiation. The enhanced photocatalytic degradation ability of FO/rGO nanocomposite is studied against both tetracycline and ibuprofen molecules. [Display omitted] • Synthesis of α-Fe 2 O 3 /rGO nanocomposite is achieved through hydrothermal technique. • UV-DRS analysis show the visible light absorption ability of prepared α-Fe 2 O 3 /rGO nanocomposite. • Photocatalytic degradation ability of α-Fe 2 O 3 /rGO is studied against ibuprofen and tetracycline. • BET analysis show the formation of mesoporous nanostructures. [ABSTRACT FROM AUTHOR]

The uses of sweet potato tubers rely on the physicochemical and functional properties of its starch. The different properties studied from 14 lines include cooking quality, extractable starch, dry matter, starch, sugar, carotenoids, and anthocyanin. The properties of extracted starch like swelling volume, solubility, amylose content, clarity of paste, rheological properties were examined. The organic matter content of different lines almost remained the same. Starch content of the tubers was greater than 20% and the sugar content ranged from 1-3%. The extractable starch was in the range of 16-21%. The anthocyanin content was high for ST- 13, while ST- 14 was rich in carotene. The swelling volume was comparatively low and the solubility ranged from 8.81-13.65%. Most of the starches examined in this present study displayed excellent viscosity properties with peak viscosity greater than 3000 cP. This study revealed that many lines have excellent potential for use as nutritive and calorific food and as industrial raw material. [ABSTRACT FROM AUTHOR]

In this study, Fe 2 O 3 nanoparticles were produced by using Leucas aspera and Jatropha podagrica leaf extract by simple green-synthesis technique. The synthesized nanostructures were analyzed by using various characterization techniques such as XRD, FT-IR, UV-DRS, SEM-EDX and TEM analysis. The XRD results show shows the formation of highly crystalline nanoparticles with the crystallite size of about 59.11 and 44.72 nm for FOLA and FOJP nanoparticles, respectively. The formation of highly agglomerated spherical nanoparticles was identified using SEM and TEM analysis. The highly pure nature of as-prepared green treated Fe 2 O 3 nanoparticles was confirmed by EDX analysis. The UV-DRS results show the visible light absorption ability of green treated Fe 2 O 3 nanoparticles with bandgap energies of about 2.42 eV and 2.50 eV for FOLA and FOJP nanoparticles, respectively. The photocatalytic degradation ability of as-prepared FOLA and FOJP nanoparticles were examined against Methylene blue and Rhodamine B dye molecules. The photocatalytic degradation efficiency of FOLA nanoparticles against MB and RhB was found to be 97% and 91%, respectively. The antibacterial properties of as prepared Fe 2 O 3 nanoparticles were studied against Escherichia coli bacterial strain and we observed great zone of inhibition. [Display omitted] [ABSTRACT FROM AUTHOR]

An eco-friendly ternary CeO 2 /SnO 2 /rGO (CSG) nanostructured photocatalyst was successfully synthesized via hydrothermal process. The nanocomposites material was characterized various analytical techniques such as X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and thermogravimetric analysis (TGA). The synthesized CSG nanocomposites were used to remove methylene blue (MB) as a model organic pollution under solar light irradiation. The MB removal efficiency of CSG was found 95% for 90 min, which is showing synergy between binary composites CeO 2 /rGO and SnO 2 /rGO. The enhanced photocatalytic system is described in terms of increased light absorption intensity, reduced bandgap which enable the electron transfer, scavengers of the reactive species and prolonged photogenerated charge carriers. Also, this material was used to remove heavy metal ions (Pb 2+ and Cd 2+ ) in wastewater via batch equilibrium method have been studied. Unexpectedly, CSG nanocomposites was used photocatalyst against bacterial growth (gram-negative E. coli and gram-positive S. aureus ) in aqueous solution. The synthesized catalyst having capability for enhance photoactive nanocomposites open up a new opportunities in various areas in photocatalysis. [ABSTRACT FROM AUTHOR]