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Ultrafine NiAl2O4 nanoparticles were prepared by simple one-pot chemical precipitation route. The precursor materials used were nickel nitrate hexahydrate and aluminum nitrate nonahydrate (as the basic materials) and sodium hydroxide (as a precipitator material). In a typical experiment, aqueous nitrate solutions were added drop wise to the alkaline solution in a magnetic stirrer under stirring. The resultant dark green colored precipitate was washed with water/ethyl alcohol (1:1 v/v) and dried. Finally, the sample was heat treated at 800 °C for 3 h in order to get the phase pure product. The prepared NiAl2O4 nanoparticles were characterized by XRD, FTIR, particle size analysis, SEM and UV. The band gap energy (Eg) of NiAl2O4 was found to be 3.05 eV. The photocatalytic degradation of malachite green and methylene blue over NiAl2O4 under visible light was carried out and the obtained results were discussed in this article. [ABSTRACT FROM AUTHOR]

The residual stresses are responsible for most of the failure of weldments in nuclear industry and the temperature distribution is the key measure to predict these residual stresses. The residual stresses are produced due to the non-uniform heating and cooling of the material and thus generating inhomogeneous plastic deformation in the components during the welding process. The Plasma arc welded 2 mm thick Ti-6Al-4V plate is taken for the study to predict the weld bead geometry, temperature distribution and residual stresses. The temperature distribution is predicted through the transient thermal analysis in ANSYS Parametric Design Language (APDL) using Three-Dimensional Conical Heat Source Model & Dhinakaran's model and the simulated results are validated against the experimental outcomes. The temperature-dependent material properties with the temperature range varying from the room temperature to the melt pool temperature are considered for transient thermal analysis. The radiation heat transfer becomes predominant at high-temperature regimes; hence the radiation effects are imposed into the convective heat transfer coefficient. The weld bead geometry, temperature distribution and the residual stresses are predicted at various regimes of the plate. It is observed that the theoretical values obtained from the FEM Simulation are good in agreement with the experimental values. [ABSTRACT FROM AUTHOR]

In situ one pot synthesis of coumarin based dithiocarbamates have been studied under conventional and microwave methods. Syntheses of coumarin based dithiocarbamates have been optimized using NaOH, K3PO4 as a base in conventional method whereas K3PO4 has given good yields in less time. The syntheses of dithiocarbamates have been carried out under microwave conditions using K3PO4 as base. The generality of microwave method has been demonstrated by synthesizing a variety of substituents in excellent yields, having short reaction time with good purity compared to those under classical conditions. All the products have been characterized by their IR, GC-MS, 1H and 13C NMR spectral data. Except 2h, 2k, 2l, all these compounds have complete DNA cleavage activity. [ABSTRACT FROM AUTHOR]

Widely distributed in nature, coumarins are one of the more common and well-known representatives of a flavonoid class. Nevertheless, they exhibit a strong and broad variety of biological activities. In the present research study, we describe a series of naphthalene and quinoline, furan and thiophene derivatives fused with a coumarin scaffold. The compounds have been interpreted by IR, GCMS, and NMR spectral studies and evaluated in vitro for their antimicrobial activities against four different pathogenic bacterial strains such as E. coli, P. aeruginosa, K. pneumonia, S. aureus and S. faecalis and fungal strains such as A. flavus, A. fumigatus and B. albicans. The coumarins fused with thiophene ring exhibit promising anti-microbial properties. [ABSTRACT FROM AUTHOR]

Design of energy efficient routing protocols for Wireless Sensor Network (WSN) is a great challenge for researchers. Recently, WSNs have gained lot of popularity and many energy efficient routing solutions are proposed. Most of the existing routing protocols focus on cluster head election and ignoring other important aspects of routing such cluster formation, data aggregation, etc. This research article presents a hybrid cluster head election for WSN based on firefly and harmony search algorithms. The contributions of the proposed protocols are (1) two level cluster head election strategy. In the first stage harmony search algorithm is used to determine initial set of energy efficient cluster head nodes that are sufficiently separated from on another by certain optimal distance. Then tentatively elected cluster head nodes are refined by firefly algorithm by considering the parameters such as node density, cluster compactness and energy to be consumed. Sometimes nature inspired optimization techniques may end up in early convergence and to avoid such problems, cluster head election scheme is divided at two levels. (2) a refined cluster formation strategy is designed where a normal node has privilege of joining to cluster head node either based on distance based metric or based on residual energy of cluster heads. This process of cluster formation helps in reduced energy consumption. The presented protocol is compared with some of the well-known clustering protocols such as LEACH, LEACH-C, EOICHD, and simple firefly based routing protocol based on the evaluation metrics such as number of alive nodes, energy consumption of network, number of packets received by Base Station, First Node Dead, Half Node Dead and Last Node Dead. Implementation is carried out using Network Simulator (NS 2.34) and results show that proposed hybrid cluster head election scheme outperforms the mentioned routing protocols. [ABSTRACT FROM AUTHOR]

Abstract The petroleum fuels need a constraining research for another energy source as the diminish of diesel fuels and causes of health problems. This paper studies the castor biodiesel as another source of fuel for already having CI engines with the application of new biodiesel which having new fuel properties. The study explains the utilization of castor biodiesel as another fuel for the diesel, and it may considerably weaken the exhalation of greenhouse gases as well as strengthen the castor seed production which gives employment to farmers on the city or town sides. The study reveals that the usability of castor biodiesel as another source of fuel reduces carbon monoxide to 9% correlated to diesel HC reduced by 8.8% also a considerable reduction in oxides of nitrogen. Here there was increased in SFC by 4% and the thermal efficiency reduced by 2.2%. But the environmental issues and the employment for farmers and increase their production of castor plant prefers the castor biodiesel is another source of fuel for the automobiles, cultivation and power production sectors. Highlights • Environmental defects caused by Fossil fuel. • Biodiesel Production method. • Produces the employment and protects the cultivating. • Performance and emission studies of diesel and biodiesel. • Characterization and test fuel blends. [ABSTRACT FROM AUTHOR]

Friction and wear studies enable the investigation of material interaction between two sliding surfaces in contact. In the present investigation, the coefficient of friction and the wear resistance of AISI 316 L parts were studied under self-mating, dry sliding conditions using a pin-on-disc type configuration. The experiments were conducted at vacuum based high temperature pin-on-disc tribometer. The 4mm diameter pin and 180mm diameter disc were subjected to varying sliding velocities (0.5, 0.75 and 1.5m/s) and were operated in 200, 400, 500 and 580 °C temperature at 600 Torr vacuum. The variation of specific wear rates with sliding velocities and different environmental conditions was studied. The morphology of sliding/rubbed surfaces was observed using Scanning Electron Microscope. In summary, it was found that a severe to mild wear transition occurred in sliding under operating conditions. Increased wear rates have been observed for 500 and 580 °C with increasing sliding velocity. Adhesive wear has been found to be predominant at 500 and 580 °C where as de-lamination has been observed at ambient temperature, 200 and 400 °C in vacuum. The present paper also carried out the numerical analysis of the vibration behavior of AISI 316 L under thermal environment. Results revealed that at high temperature vibrational amplitude and natural frequency is significantly reduced. This can be attributed to the reduction in stiffness of the material at elevated temperatures. This high amplitude vibration during service can lead to high wear rate. [ABSTRACT FROM AUTHOR]

Nowadays automotive industries altered their core on the custom-made result. They are making medium and small batch production by covering an increasing offer, that the sheet metal forming dies are cost-effective manufacturability. Replete polymers undertake capabilities to fulfil such vital parts in the boundary of prototype tools manufacturing or in the small set production of sheet metal components. For sheet metal forming this paper declares investigations distribute tool designing and tribological form of using some materials like polymeric materials. Two polymer composites i.e. friction and wear on sheet metal simulated materials have been investigated, strip, drawing test testability is discussed and presented using the linear wear distance relation W1/s measured with the new testing method to anticipate lifetime of polymeric stamping dies using sheet materials with structured surfaces. A meaningful improvement in wear and friction performance of polymer or polymer composite has been observed and abstract model for rough wear and friction of polymer blend is given. Sheet metal counter material combination has been developed, based on the after effect accomplished by measurement of wear and friction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Demonstration of scalable synthesis of synergistic N-(Nb 2 CT x /rGO). • The inherent low performance of Nb 2 C is mitigated by Nitrogen doping. • The best material delivered a maximum specific capacity of 816 F/g at 2 A/g. • The fabricated supercapacitor exceeding stability of 100 K with ∼100% retention. To enhance high-rate cycle stability and energy density of supercapacitors, highly effective electrode materials are essential. Two-dimensional (2D) materials are anticipated to rank among the most remarkable compounds for use in the energy sector. The expected ability to store energy in two 2D materials, reduced graphene oxide (rGO) and Nb 2 C MXene through making a hetero-assembly, is demonstrated in this research for the first time by dual N doping on both lattices using the supercritical fluid processing method. To the best of our knowledge, the supercritical fluid synthesis of the 2D/2D MXene-based hetero-assembly is unique and distinctive. The high charge storage ability of N-(Nb 2 C/rGO) sites and the typical reaction kinetics all add to the outstanding electrochemical performance of the engineered hetero-assembly through this unique synthetic procedure. The N-(Nb 2 C/rGO) consequently displays exceptional electrochemical performance with a high specific capacitance of 816 F/g at a current density of 1 A/g and an admirable energy density of 29 Wh/kg in aqueous H 2 SO 4 electrolyte, and 33 Wh/kg in non-aqueous TEABF 4 /ACN electrolyte. Furthermore, after 100,000 rounds of charging and discharging, the capacitance retention is still keeping 100% of the initial capacitance in quasi-solid-state PVA/H 2 SO 4 based electrolyte. Herewith this current study offers insights into the modulation of energy storage ability and the logical design of high-performance N-dual doped MXene/rGO based hetero-assembly for electrode material from aqueous to non-aqueous to quasi-solid-state supercapacitors. [ABSTRACT FROM AUTHOR]

This paper presents the studies carried out on bending and free vibration behavior of truss core sandwich panel filled with foam typically used in aerospace applications. Equivalent stiffness properties for foam-filled truss core sandwich panel are derived by idealizing 3D foam-filled sandwich panel to an equivalent 2D orthotropic thick plate continuum. The accuracy of the derived elastic property is ensured by the numerical comparison of free vibration response of 3D and its equivalent 2D finite element model. The derived stiffness constants were used in closed form solution to evaluate the maximum deflection of the continuum. The results show that the free vibration and static behavior of the sandwich panel can be enhanced in due consideration to the space constraint by filling foam in the empty space of core. The results also reveal that triangular core foam-filled sandwich panel deflects less compared to other cores. From the free vibration analysis, effect of filling foam is effective in cellular and trapezoidal core. [ABSTRACT FROM AUTHOR]

In this paper, the author established the general solution and generalized Ulam--Hyers--Rassias stability of n-dimensional additive functional equation ... in generalized 2-normed space. [ABSTRACT FROM AUTHOR]

The existing LTrP method shows the relationship between the reference pixel and its neighbor’s, based on the four directional code that are computed using the first-order derivatives in both vertical and horizontal directions. It is apparent that the performance of LTrP can be improved by differentiating the edges in more than four directions. This observation has motivated us to propose a nine direction code referred to as Local Multi Code Pattern (LMCP). LMCP extracts supplementary directional information as compared with LTrP. The performance analysis of the aforementioned techniques were done with the help of ORL, Yale, Jaffee databases and also the recital analysis on the same significantly improves the recognition rate of the proposed method. [ABSTRACT FROM AUTHOR]

Sandwich panel which has a design involving acoustic comfort is always denser and larger in size than the design involving mechanical strength. The respective short come can be solved by exploring the impact of core geometry on sound transmission characteristics of sandwich panels. In this aspect, the present work focuses on the study of influence of core geometry on sound transmission characteristics of sandwich panels which are commonly used as aircraft structures. Numerical investigation has been carried out based on a 2D model with equivalent elastic properties. The present study has found that, for a honeycomb core sandwich panel in due consideration to space constraint, better sound transmission characteristics can be achieved with lower core height. It is observed that, for a honeycomb core sandwich panel, one can select cell size as the parameter to reduce the weight with out affecting the sound transmission loss. Triangular core sandwich panel can be used for low frequency application due to its increased transmission loss. In foam core sandwich panel, it is noticed that the effect of face sheet material on sound transmission loss is significant and this can be controlled by varying the density of foam. [ABSTRACT FROM AUTHOR]