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Submerged Friction Stir Welding is a modification of the friction stir welding process in which the water as the coolant is employed to standardize the temperature. It is considered as a green and environmentally friendly welding technology because of low energy consumption, no gas emission, and no need for consumable material. It is applied to structural purposes like oil platforms and pipelines, or in industrial and laboratories for enhancing the weld strength. This review paper is classified into three categories, the first one studies the preceding experimental investigations, the second one is modelling/optimization, and the third one is current status and development of submerged friction stir welding. The experimental results of the previous research findings in submerged friction stir welded sample with performance characteristics, tensile properties, microhardness, fracture analysis and corrosion resistance, macro/microstructure analysis on the various materials are discussed. This review articles concludes with recommendations for future research exertion.

An interturn short-circuit in the stator windings can lead to the breakdown of electrical machines. In the case of induction machines, several fault detection methods and faulted models have been developed in the recent decades. These models differ mainly in how the leakage inductances of the faulted winding are modeled. This work provides a generalized model for interturn short-circuit faults, using different assumptions for the leakage inductances. The model is validated with experimental results for an exhaustive set of fault parameters, and the influence of leakage inductances is analyzed. Moreover, the model is used to analyze the drawbacks of the negative-sequence fundamental current as a traditional fault signature. A high-frequency injection method for converter-fed machines is presented to overcome these limits. The proposed fault signature is the negative-sequence current at the injection frequency and it is evaluated experimentally at different operating conditions. The fault severity and its location are proved to be related to the proposed fault signature.

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ABSTRACTFriction stir welding (FSW) is an upgraded version of the friction welding process. It was invented in 1991 at The Welding Institute (TWI). It is considered the latest in development and also the most important one in the metal joining process during the past two decades. The present investigation has the objective of comparing the mechanical and metallurgical properties of welding processes such as GTAW, GMAW, and FSW lap joints on the welded AA6061-T6 alloy. Rolled AA6061-T6 plates of 3 mm thickness were used as the base material for preparing lap welded joints. All the welding processes were carried out using optimum parameter conditions. The failure load, tensile shear strength, and the micro-hardness of the welded joints were analysed using a universal tensile test machine and the Vickers’s hardness testing machine. The microstructures of the welded joints were analysed using an Optical Microscope (OM) and a Scanning Electron Microscopy (SEM). Finally, a comparative analysis was done between the results of the general aspects like power and heat input, mechanical and metallurgical properties of TIG, MIG, and FSW lap joint specimens.

ABSTRACTNeurodegenerative diseases (ND) are characterised by loss of neurons in the brain and spinal cord. For the normal functioning of the brain, divers group of fatty acids in the form of glycerophospholipids, glycerol ether lipids, cerebrosides, sulfatides, and gangliosides are essential. They are present abundantly in the nervous system and are actively involved in both the development and maintenance of the nervous system. A dietary deficiency of essential fatty acid during development results in hypomyelination state which affects various neuronal functions. Several studies suggested that age remains the primary risk factor for almost all neurodegenerative disorders. The potential contribution of these fatty acids in the progression of neurodegenerative disorders is indispensable. Erucic acid an omega 9 fatty acid, which is obtained from edible oils has proven to cause myocardial lipidosis, heart lesions and hepatic steatosis in animals therefore, its content in edible oils is restricted to certain levels by regulatory agencies. However, erucic acid in the form of a mixture with oleic acid is often used as a dietary treatment for the management of adrenoleukodystrophy without any cardiotoxicity. Our literature search revealed that, erucic acid reported to enhance cognitive function, interact with peroxisome proliferator activated receptors (PPARs), inhibit elastase and thrombin. In this review first we have attempted to describe the relationship between fatty acids and neurodegeneration followed by a description on the pharmacology of erucic acid. The overall purpose of this review is to analyse toxic and beneficial neuropharmacological effects of erucic acid.

Applying dual heteroatom doping strategies to synthesize carbon materials has attracted tremendous interest in improving supercapacitor performance, due to their exemplary high specific surface area (SSA), ordered porous structure, highly accessible special pores, and uniform distribution of heteroatoms in the carbon structure. In this work, we prepared highly ordered N, P and N, S dual-doped carbon (NPC/NSC) with the utilization of 2D hexagonally ordered Santa barbara amorphous (SBA-15) silica supporting material to analyze the P/S doping effect on N-doped carbon towards supercapacitor activity. The addition of minimum amounts of secondary heteroatom precursor in the N-doped SBA-15 template can significantly influence the physiochemical properties and supercapacitor performance of the resulting NPC/NSC materials. The NSC material significantly improves the surface area (951 m2 g−1), good replicated porous morphology, higher doping content of N (1.61 at.%) and S (0.62 at.%), enriched pyrrolic (17.3 %) and pyridinic N (19.0 %) concentrations and higher defect sites (ID/IG = 1.06) which leads to greatly enhances capacitance performance than that of NPC. In addition, NSC effectively improves higher specific capacitance of 480 F g−1at a current density of 2 A g−1. Further with redox additive the specific capacitance has increased to 910 at 2 A g−1with a power density of 22.2 kW kg−1and higher energy of 80.9 Wh kg−1in 0.01 M hydroquinone redox additive in 1 M H2SO4electrolyte solution.

In this paper, we propose a new radical third root functional equation and determine its solution in the domain of positive real numbers. Also, we validate the stability of this equation in modular and β-homogenous spaces pertinent to Ulam stability theory. We provide few counter-examples to invalidate the stability results for singular cases. A simple occurrence of this equation in real-life application is also presented.

Coupling electrochemical CO2reduction with renewable energy sources is one of the best ways to minimize the carbon footprint in the atmosphere. Viable technology can be designed with the aid of an electrocatalyst which can be easily scalable and selectively reduces CO2at lower overpotentials, i.e.ought to be energy efficient. In this context, we utilised the microwave polyol method to synthesis and systematically tune the oxygen vacancies of an SnO2–CNT composite by varying the particle size. The extent of the oxygen vacancy formed was confirmed with the help of Raman, XPS and EPR studies. The oxygen vacancy has the ability to lower the activation barrier for CO2−formation. Oxygen vacancy variation has altered the onset potential and the selectivity towards formate production of SnO2–CNT composites. A distinction in the electrocatalytic activity may arise from the difference in CO2adsorption and intermediate binding strength and desorption. Among all the catalysts, SnO2–CNT pH-11 stands out with the highest faraday and energy efficiency of 76 and 54% towards formate production at −0.77 V vs.RHE, respectively. This catalyst exhibits an excellent stability and produces 16 mM of formate with ∼60% Faraday efficiency after a long term run of 10 hours.

Localization is one of the key issues in wireless sensor networks. Several algorithms and techniques have been introduced for localization. Localization is a procedural technique of estimating the sensor node location. In this paper, a novel three hybrid algorithms based on firefly is proposed for localization problem. Hybrid Genetic Algorithm-Firefly Localization Algorithm (GA-FFLA), Hybrid Differential Evolution-Firefly Localization Algorithm (DE-FFLA) and Hybrid Particle Swarm Optimization -Firefly Localization Algorithm (PSO-FFLA) are analyzed, designed and implemented to optimize the localization error. The localization algorithms are compared based on accuracy of estimation of location, time complexity and iterations required to achieve the accuracy. All the algorithms have hundred percent estimation accuracy but with variations in the number of fireflies’ requirements, variation in time complexity and number of iteration requirements.

Developing an efficient electrocatalyst for improving oxygen reduction reaction (ORR) kinetics is essential for various renewable energy appliances and energy-intensive technologies. The design of a low cost and robust ORR catalyst with desired durability still remains a challenging task. Here we demonstrated a facile and environmentally friendly supercritical fluid-assisted decoration of Co3O4on multi-walled carbon nanotubes (MWCNTs) to generate a hybrid nanostructure electrocatalyst for ORR. The mildly oxidized MWCNTs provided functional groups on the outer walls to seed and anchor nanocrystals, while keeping the inner walls intact for a highly conducting network. In particular, the 11 wt% Co3O4-MWCNTs hybrid exhibited improved half wave potential by 240 mV compared to Co3O4and 125 mV with respect to MWCNTs based on the rotating ring disc voltammetry results. Similarly, the observed ORR current density was superior to those of both bulk Co3O4and bare MWCNTs at medium overpotential, proceeding dominantly through a 4-electron reduction pathway. Such enhancement may be attributed to the synergetic effect of the specific heterogeneous architecture, which results in improved conductivity, accessible active centres and enhanced reaction rate at Co3O4decorated on the MWCNT surface.

We studied the cardioprotective effect of squalene on isoprenaline-induced myocardial infarction in male albino rats with respect to changes in the levels of lipid components in plasma and heart tissue. Prior administration of 2% squalene in feed for 45 days significantly reduced the isoprenaline-induced elevation in the levels of cholesterol, triglycerides, and free fatty acids in plasma and heart tissue of rats following myocardial infarction. It exerted an antilipidemic effect by reducing the level of low-density lipoprotein cholesterol with a parallel rise in the level of high-density lipoprotein cholesterol in plasma of experimental rats. A tendency to prevent the isoprenaline-induced depletion of phospholipids in the myocardium of experimental rats was also observed. In the present study, the pretreatment with squalene significantly counteracted the isoprenaline-induced lipid peroxidation and maintained the rats at near normal status. The results of the present study indicate that the overall cardioprotective effect of squalene is probably related to an inhibition of lipid accumulation by its hypolipidemic properties and/or its antioxidant properties.

We have examined the protective effect of taurine on the myocardial antioxidant defense system in isoprenaline (isoproterenol)‐induced myocardial infarction in rats, an animal model of myocardial infarction in man. Levels of diagnostic marker enzymes in plasma, lipid peroxides and reduced glutathione, and the activity of glutathione‐dependent antioxidant enzymes and antiperoxidative enzymes in the heart tissue were determined. Intraperitoneal administration of taurine significantly prevented the isoprenaline‐induced increases in the levels of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, and creatine phosphokinase in the plasma of rats. Taurine exerted an antioxidant effect against isoprenaline‐induced myocardial infarction by preventing the accumulation of lipid peroxides and by maintaining the level of reduced glutathione and the activity of glutathione peroxidase, glutathione‐S‐transferase, catalase and superoxide dismutase at near normality. The results indicated that the cardioprotective potential of taurine was probably due to the increase of the activity of the free radical enzymes, or to a counteraction of free radicals by its antioxidant nature, or to a strengthening of myocardial membrane by its membrane stabilizing property.

We have examined the protective effect of taurine on the myocardial antioxidant defense system in isoprenaline (isoproterenol)-induced myocardial infarction in rats, an animal model of myocardial infarction in man. Levels of diagnostic marker enzymes in plasma, lipid peroxides and reduced glutathione, and the activity of glutathione-dependent antioxidant enzymes and antiperoxidative enzymes in the heart tissue were determined. Intraperitoneal administration of taurine significantly prevented the isoprenaline-induced increases in the levels of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, and creatine phosphokinase in the plasma of rats. Taurine exerted an antioxidant effect against isoprenaline-induced myocardial infarction by preventing the accumulation of lipid peroxides and by maintaining the level of reduced glutathione and the activity of glutathione peroxidase, glutathione-S-transferase, catalase and superoxide dismutase at near normality. The results indicated that the cardioprotective potential of taurine was probably due to the increase of the activity of the free radical enzymes, or to a counteraction of free radicals by its antioxidant nature, or to a strengthening of myocardial membrane by its membrane stabilizing property.

This article discusses the development and application of nanofibers, nanocomposites, nanotechnology in the textile industry, and nanotechnology in smart textiles. Electro spinning is the best way of producing polymer nanofibers. The process is versatile in that there is a wide range of polymer melts or solutions that can be spun. The process involves the application of a strong electric field applied to a syringe-shaped die connected to a reservoir containing a polymer solution or polymer melt and a ground plate, the counter electrode. To obtain nanotubes and nanocables there are two novel approaches. One route employs ultra-thin polymer fibers with diameters well down in the 10 nm range as templates. The fibers, which are obtained by the electrospinning process, are coated with polymer precursors by chemical vapor deposition. In a subsequent step, the template fibers are removed by extraction or pyrolysis. The second route involves wetting of an array of cylindrical sub micrometer nanoporess by polymers in the molten state. For templates possessing pore walls consisting of aluminum oxide or silicon oxide, which are high-energy surfaces, a complete wetting of the pore walls by polymers will take place.

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Crystallization of carboxylic acids with molecules containing complementary hydrogen bonding groups, e.g., 4,4‘-bipyridine, phenazine, and 2-pyridone, is an active pursuit in crystal engineering. We describe in this paper an addition to this family of spacer ligands, trans-1,4-dithiane-1,4-dioxide 4, a molecule that forms complexes with carboxylic acids via O−H···O and C−H···O hydrogen bonds. Analysis of hydrogen bonding in the molecular complexes of 5-nitrosalicylic acid 6, 3,5-dinitrosalicylic acid 7, succinic acid 8, and oxalic acid 9 with disulfoxide 4 shows that these crystal structures are stabilized by acid-sulfoxide and sulfoxide-sulfoxide supramolecular synthons XII and XIII. The preference for acid−sulfoxide recognition in crystals is explained through database analysis and energy computation.

Conformational differences between two independent molecules in the same crystal of the title triaroylbenzene derivative give rise to an interpenetrated structure involving two dimensionally distinct networks—a 2D hexagonal and a 3D α-polonium-type.

Conformational differences between two independent molecules in the same crystal of the title triaroylbenzene derivative give rise to an interpenetrated structure involving two dimensionally distinct networks—a 2D hexagonal and a 3D α-polonium-type.

The T-geometry of O–H⋯O and C–H⋯O hydrogen bonding groups in the title molecule (5-NSA) form a brick wall network that is modularly expanded and transformed to chair cyclohexane and honeycomb architectures in molecular complexes with trans-1,4-dithiane-1,4-dioxide and dioxane. The variation in hydrogen bond synthons results in different examples of topologically related (6,3) nets.