Thermophysical analysis of acrylic pyramid solar still with and without Zn2+ substituted Cr2O3 nanoparticles had been analysed. Synthesised pure and Zn2+ doped Cr2O3 nanoparticle with different dopant concentrations is used along with the black absorber paint as an additional source in enhancing the heat transfer in the solar still. Heat transfer modes, efficiency (instantaneous and overall) and thermophysical properties are predicted for solar still with and without Zn2+ substituted Cr2O3 nanoparticles. XRD confirms the rhombohedral phase with average particle size of pure and Zn doped Cr2O3 around +/- 14 nm and +/- 12 nm respectively. Surface morphology showed nearly spherical shape with loosely agglomerated and the presence of Cr and Zn was confirmed by EDAX analysis. Dielectric measurements showed enhanced dielectric constant and electrical conductivity as the function of temperature at different frequency range. Performance ratio observed during the study is in the range of 2.11 to 10.125 for solar still alone, 2.38 to 11.9 % for solar still with pure Cr2O3 nanomaterial, 2.38 % to 12.87 % for solar still with 2.5 mol.% Zn2+ doped Cr2O3 nanomaterial, 2.46 % to 13.22 % for solar still with 5 mol.% Zn2+ doped Cr2O3 nanomaterial and 2.54 % to 13.67 % for solar still combined with 7.5 mol.% Zn2+ doped Cr2O3 nanomaterial. Average daily output of solar still was found to be 2.366 L/day, 3.147 L/day, 3.299 L/day, 3.3761 L/day and 3.628 L/day for pyramid solar still under five modes of study. Efficiency of the still was calculated as 18.29%, 21.15%, 21.88%, 22.32% and 23.48% for pyramid solar still under five modes of study. It is found that the productivity yield of solar still with 7.5 mol.% Zn2+ doped Cr2O3 nanomaterial is increased to higher level due to the increased absorption of solar radiation when compared to other modes of study. (c) 2021 Elsevier Ltd. All rights reserved. Selection and Peer-review under responsibility of the scientific committee of the Global Conference on Recent Advances in Sustainable Materials 2021.

Performance study of ZnO/Al2O3 nanocomposites in escalating the productive yield of pyramid solar still coupled with shallow solar pond using escalated heat transfer coefficient had been analyzed. Shallow Solar Pond (SSP) of area 0.8 m2 used as additional source of transferring heat to Pyramid Solar Still (PSS) of area 0.25 m2. Heat transfer values, instantaneous and overall efficiencies are predicted for the PSS with and without ZnO/Al2O3 nanocomposites. Saturation vapor pressure (SVP) predicted is in the range of 48521.62–11889.52 Pa and 5121.7 to 13281.98 Pa for studies without and with ZnO/Al2O3 nanocomposites. In ZnO/Al2O3 coated pyramid still coupled with shallow solar pond, SVP is upheld at off sunshine hours as a result of heat absorbing by ZnO/Al2O3 nanocomposites in addition to thermal storage of SSP. Observed latent heat is around 2,416,722.46–2,375,960.52 kg−1 and 2,414,341.48 to 2,370,510.43 kg−1 for solar still with SSP under two modes. Performance ratio for solar still with SSP under two modes of study is observed in the range of 2.11–10.60

Pure V 2 O 5 and MnO 2 /V 2 O 5 hybrid nanocomposites were synthesized by microwave-assisted method for electrochemical supercapacitor application. X-ray diffraction analysis showed the orthorhombic structure for pure V 2 O 5 and MnO 2 /V 2 O 5 nanocomposites that showed the mixed state of the orthorhombic and orthogonal phase structure of V 2 O 5 and MnO 2 . The average crystalline sizes were calculated as 14 nm and 17 nm for pure V 2 O 5 and MnO 2 /V 2 O 5 nanocomposites. Scanning electron microscopy and Field emission scanning electron microscopy image analysis demonstrated the mixed state of nanoplate and small rod-like shape for V 2 O 5 and it was transformed to nanobeads shape by the addition of MnO 2 . The Energy Dispersive X-Ray Analysis confirmed the presence of V and Mn compounds in the as-prepared nanocomposites. The porous nature of nanostructures was studied by Brunauer–Emmett–Teller analysis. Finally , the electrochemical analysis was recorded in 3.5 M KOH and 1 M H 2 SO 4 electrolytes to compare its performance and suitability. The pure V 2 O 5 nanostructure showed the maximum capacitance of 150 F/g and 95 F/g in KOH and H 2 SO 4 electrolytes. The specific capacitance of V 2 O 5 was enhanced to 570 F/g for the addition of 6 wt% of MnO 2 in 3.5 M KOH electrolyte, whereas, in 1 M H 2 SO 4 electrolyte, the specific capacitance was 269 F/g for the addition of 6 wt% of MnO 2.

Nonlinear optical crystalline material is the fascinating tool for the optoelectronic devices and for phase-matched equipments, frequency matching circuits and etc. Present study portrays the synthesize and utility of macro and nano scaled crystals of 2-[4-(trifluoromethyl) phenyl]-1H-benzimidazole (TFMPHB) by slow evaporation solution growth method and by milling conversion. As-prepared crystals were studied by XRD, CHNSO analysis, dielectric and tribology-mechanical, NLO, and photoconductivity. The orthorhombic phase structure with the average crystalline size of 21 nm was observed. The elemental composition of crystals was analyzed for the presence of elements. Tribological studies of macro and nano TFMPHB crystals were favorable for mechanical applications. Further, the high dielectric constant (363 K) at low frequency was suitable for microelectronic devices; NLO is analyzed with phase matching effect over particle size, and photoconductivity study also reported for the entitled crystalline specimen. The structural parameters by AFM and SEM, absorbance nature by UV spectra, and modeling data by computational methods are also reported.

The purpose of a survey is to use questionnaires or interviews to collect data from participants in a sample about their characteristics, experiences and opinions in order to generalize the findings to a population that the sample is intended to represent. A survey or questionnaire provides structure and standardization in the research design. It also provides the opportunity to gather large amounts of data from many respondents. A questionnaire was designed for B school alumni to study the effect of soft skills training on employability of B-School graduates in Bangalore. Measurement Model (Structural Equation Modelling - SEM) was used to establish convergent validity, discriminant validity and reliability of the above questionnaire before conducting the survey. Validity represents the capacity of an instrument/ questionnaire to ascertain what it claims to measure. Convergent validity is proven when constructs that are similar respond to one another, while Discriminant validity is said to exist if we can sufficiently differentiate two of the dissimilar constructs. Any research instrument must be totally concerned with accuracy leading to dependability, otherwise called as reliability. A reliable instrument supposes to consistently measure whatever is measured over time. The main objective of this study was to test the validity and reliability of the research instrument used to study the effect of soft skills training on employability of B-School graduates.

The twenty-first century has been witnessing much development in the technological aspect, particularly in optoelectronic device. In this continuation, we have prepared V2O5@WO3 nanocomposites for dielectric application. The proposed titled composites were prepared by a simple and cost-effective microwave-assisted wet chemical method. Subsequently, as-prepared composites were investigated by various characterization techniques. The structural and morphological analysis showed aggregated grain and rapid grain growth. The presence of functional group and elemental analysis were studied. The thermal analysis showed the thermal stability of as-prepared material. The dielectric studies demonstrated excellent dielectric behaviour with respect to temperature and frequency which would meet the required quality for optoelectronics application.

2-{2-(4-Diethylamino-phenyl)-vinyl}-1-methyl-pyridinium-tetrafluoroborate(DAPVMPTFB) organic non linear optical (NLO) crystals are grown by slow evaporation method and analyzed for XRD, carbon hydrogen nitrogen sulphur and oxygen (CHNSO) analyzer, computational, influx and dielectric studies. X-ray diffraction (XRD) analysis demonstrated the lattice parameters (a-7.8969 angstrom, b-20.4867 angstrom, c-11.1989 angstrom, alpha = gamma as 90 degrees and beta as 92.407 degrees). The chemical formula of the as-synthesized crystal is C18H23BF4N2. The presences of elements are identified theoretically and experimentally. The surface roughness of as-prepared crystal was studied by atomic force microscopy (AFM) image analysis. The NLO is 1.15 times higher than the referenced KDP specimen due to strong H atoms of 23 in the specimen. The macro influx for filters is 4.7371 mu m; the structural parameters, as well as energy, interactions and Halosian with dotted effect, molecular potential, interactions, internal in addition to the external fields, shape indexing; curvedness; fragmented patching; finger print region by computational based Hirshfeld analysis (HFA), are well portrayed using the software. The dielectric utility is mainly for industries in manufacturing semiconductors. The Oak Ridge Thermal Ellipsoid Plot (ORTEP) diagram portrays the grown crystalline structural portrayal as well as the supercell effect for special volume unit cells by software.

We have reported the preparation and characterization of both pure and Cu2+ doped Cr2O3 nanoparticles with different dopant concentrations by the simple, cost-effective microwave-assisted method. As-prepared samples have undergone various characterizations to get an insight into the Cr2O3 nanoparticles. The XRD pattern showed the rhombohedral phase structure of Cr2O3 with an average particle size of ±14 nm. The surface and morphology analysis (FESEM and TEM) revealed a nearly spherical shape with an average particle size of 30–50 nm and the presence of the elemental composition of Cr and Cu was confirmed by the EDAX spectrum. The optical properties (UV–Vis and PL spectra) of Cr2O3 nanostructures were also studied, and results were found to support our further studies. Finally, electrical and dielectric characterization showed enhanced electrical conductivity concerning temperature and frequency.

Electrochemical supercapacitors are prominent energy storage devices owing to their superior capacitive behaviour and matchless power and energy density with excellent cyclic stability. In this report, we have prepared the rod shape WO3/V2O5 nanocomposite by the microwave-assisted method. XRD analysis confirmed the rhombohedral and orthorhombic phase structure of V2O5 and WO3. Various functional groups associated with V2O5 and WO3 compounds were studied by FTIR spectrum. Surface and morphological image analysis demonstrated rod shape morphology. Surface area (22.798 m2/g), pore volume (0.137 cc/g) and particle size (18 nm) were analyzed by BET analysis. The pure V2O5 nanostructure exhibited maximum specific capacitance of 150F/g in 1 M H2SO4 electrolyte which was enhanced to 260, 265 and 386F/g respectively for various wt.% of WO3 added V2O5 nanocomposites. The long cyclic test showed 104 % of capacitance retention over 5,000 cycles with 99 % columbic efficiency.

Perovskite structured Nd0.7Co0.3FeO3 nanoparticles were synthesized through a facile hydrothermal method. The structural orientation was followed by varying the calcination temperature between 500 and 1100 degrees C. Detailed structure and morphology of the samples were investigated using various characterization techniques such as TG-DTA, XRD, FE-SEM, HR-TEM, EDX, XPS, AFM and BET study. The average particle size of Nd0.7Co0.3FeO3 nanoparticles was in 50-80 nm for the sintering temperature of 500-1100 degrees C. Well crystalline orthorhombic structure was confirmed from the XRD measurements. In addition, interesting morphological changes from non-uniform flakes to an array of spherical nanoparticles with respect to the applied temperatures was observed. The electrochemical performance of Nd0.7Co0.3FeO3 anode material has demonstrated moderate lithium ion insertion/extraction ability with average discharge capacity of about 291 mAh g(-1) after 100 cycles at 0.5 mV s(-1). The obtained charging and discharging profiles of the perovskite compound shows that it could be adopted as future electrode material for storage application.

In this work, we have prepared WO3-CdS nanocomposites for supercapacitor electrode by Microwave-Assisted Method. The orthorhombic and monoclinic mixed structure of WO3 and hexagonal structure of CdS was observed by XRD pattern. The FESEM micrograph showed the irregular particle shape and HRTEM images demonstrated the small rod shape morphology with irregularity. The EDAX analysis confirmed the presence of W and Cd elements. From the electrochemical analysis, we have calculated the maximum capacitance as 650 F/g for WO3-CdS (6 wt%) electrode. The long cycle test showed 133% of capacitance retention with 100% Coulombic efficiency.

The great challenge in front of the twenty-first century is steady and smooth green energy supply for automobiles, optoelectronics, and recently invented IoT devices. To overcome these challenges, different kinds of energy storage mechanisms were propounded. The fuel cells, electrochemical supercapacitors, and Li-ion batteries were investigated extensively for high energy and power density. Various nanostructures have been reported with several merits. But still, no metal oxide has attained the required characteristics. Among them, Tungsten trioxide (WO3) has fascinated the research people due to its excellent novel properties such as tunable optical band gap and interesting structures and morphology. Indeed, the electrochemical performance of hybrid nanocomposites of WO3 reveals the practical application of supercapacitor. In this chapter, we briefly introduced the general synthesizing methods and recent developments in WO3 based supercapacitor electrode materials have been discussed.

Design and development of an efficient and earth abundant electrocatalyst for improving the kinetics of oxygen reduction reaction (ORR) is considered as important task especially in renewable energy sector and energy-intensive appliances. In particular, developing a low cost, environmental benign, robust and stable ORR catalyst still remains a challenging task due to its sluggish kinetics. Here in this work we developed a simple and environmentally green electro-spinning technique for decoration of cobalt oxides (Co3O4) on polyacrylonitrile (PAN) fibers to generate a hybrid nanostructure of carbon nanofiber- Co3O4 (CNF- Co3O4) during calcinations and employed resultant electrocatalyst towards ORR. The CNF provided active surface to seed as well an anchoring spot for nanocrystals and act as a conducting network. The resulting CNF-Co3O4 hybrid displayed a supeior ORR current density that surpassed bare CNF and occurred via a 4 electron direct reduction pathway. It may due to the as formed heterogeneous interface during the decoration of Co3O4 on CNF leads to enhanced conductivity and thereby decreases ORR overpotential as well as enhanced reaction rate at CNF-Co3O4 surface.

Herein for the first time, we have reported the performance and characteristics of new high-voltage zinc-vanadium (Zn-V) metal hybrid redox flow battery using a zinc bromide (ZnBr2)-based electrolyte. The Zn-V system showed an open-circuit voltage of 1.85 V, which is very close to that of zinc-bromine flow cell. The obtained results exhibited a voltaic, Coulombic, and energy efficiencies of 88, 82, and 72% at 20 mA.cm(-2), respectively, in which low-cost microporous membrane was used as a separator. However, the cell tested using Nafion-117 membrane showed voltaic, Coulombic, and energy efficiencies of 84, 83, and 71%, respectively at a current density of 20 mA.cm(-2). Furthermore, the Zn-V cell performance is also compared with the Zn-Br-2 flow system to highlight the advancement of the new Zn-V system. The cell also showed stable performance up to 50 cycles at a current density of 20 mA.cm(-2).