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Three Dimensional models of proton exchange membrane fuel cell (PEMFC) comprising of flow field channels (FFP), Gas Diffusion Layers (GDL), Catalyst layers (CL) and membrane with an active area of 16 cm2 are modelled and simulated in this work. The four FFP's used in the models are Parallel, Serpentine, Fractal and Pin. In this work, a Multiphysics simulation was conducted to determine the velocity distribution, pressure distribution, molar fraction and polarization curves of a high-temperature PEMFC (ht-PEMFC) based on phosphoric acid doped polymer membranes. Polarization plot of the four models was obtained for performance prediction against flooding. Pin and Fractal showed better performance, uniform pressure and velocity distribution compared to Serpentine and Parallel patterns. [ABSTRACT FROM AUTHOR]

The advanced progression of mobile technology leads to a dramatic expansion in cellular data traffic (DT). Especially, the development of precise time series model in a 5G cellular network, becomes indispensable to increase the quality of services (QoS) and forecast cellular DT. The cellular DT predictive models allow the operator in adapting to the traffic demand of the networks with user experience and better resource usage. Furthermore, owing to the characteristics of the higher heterogeneities amongst a number of base stations with traffic load, the cellular DT predictive model becomes challenging. Thus, the study develops a detailed analysis of artificial intelligence (AI) based techniques to predict mobile DT. An extensive analysis of existing ML model has been presented for the cellular DT prediction in 5G network. Additionally, a wide-ranging description of the advancement of mobile networks is provided. Likewise, the present approaches are studied in different ways including underlying methodologies, merits, major objectives, performance measures, and inferences. Also, wide-ranging experimental analyses of the surveyed methods have been taking place for recognizing the exclusive features of all approaches. Lastly, an overview of future directions and challenging issues are extensively discussed. [ABSTRACT FROM AUTHOR]

Tungsten bronze type cerium doped strontium barium niobate (Ce:SBN - Sr0.6B0.4Nb2O6) ceramics were synthesized by solid state process. Cerium was used as dopant to improve its electrical properties. Influence of Ce+ ions on the photoluminescence properties was investigated in detail. The grain size topographical behavior of SBN powders and their associated abnormal grain growth (AGG) were completely analyzed through SEM studies. Finally dielectric, measurement discusses about the broad phase transition observed due to cerium dopant The results were discussed in detail. [ABSTRACT FROM AUTHOR]

In this paper, ZnO and ZnO:Al nanopowders have been synthesized by low cost hydrothermal method. Zinc nitrate, hexamethylenetetramine (HMT) and aluminium nitrate are used as precursors for ZnO and AZO with different molar ratios. The structural and optical characterization of doped and un-doped ZnO powders have been investigated by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDAX), photoluminescence (PL) and ultra violet visible (UV-Vis) absorption studies. The SEM results show that the hydrothermal synthesis can be used to obtain nanoparticles with different morphology. It is observed that the grain size of the AZO nanoparticles increased with increasing of Al concentration. The PL measurement of AZO shows that broad range of green emission around 550nm with high intensity. The green emission resulted mainly because of intrinsic defects. [ABSTRACT FROM AUTHOR]

Lithium 5 wt% doped V2O5 thin film was deposited onto ITO substrate by spray pyrolysis technique. The substrate temperature was kept at 450 °C. 200 MeV Ag15+ ion beams at a fluence of 5×1012 ions/cm² was irradiated on 5 wt% 'Li' doped V2O5 film of thickness 1367 nm. The XRD pattern confirms that the pristine film is non stoichiometry with orthorhombic structure and upon irradiation the crystallinity decreased and an obvious textured growth along (020) plane is induced. Raman peak observed at 917 cm-1 is due to oxygen deficiency. Upon irradiation, the optical transparency and band gap of the film decreased. Electrical transport property study shows that the resistivity increased by one order for the irradiated film. [ABSTRACT FROM AUTHOR]

An inexpensive preparation method is being reported for obtaining erbium doped gadolinium oxide (Er5%:Gd2O3) nanoscale rods. The elongated nanoscale systems, as-formed through a co-precipitation process, are characterized by using X-ray powder diffraction (XRD) patterns, scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) mapping, Ultra Violet-visible (UV-vis.) absorption spectroscopy and photoluminescence (PL) spectroscopy. In addition, the Williamson-Hall (W-H) plot is also performed to distinguish the effect of crystalline size-induced broadening and strain-induced broadening at full-width at half-maximum (FWHM) of the XRD profile. The XRD patterns of as-formed and calcined products show that the phase confirmation. As revealed from the SEM micrographs, the morphology of the products show that the rod-like nanoparticles. The EDX micrographs show that the presence of elements in our samples. The band gap values in calcined samples are found to be in the range of 3.569 eV. Upon 230 nm excitation on calcined samples, three broad emission peaks are observed from PL studies. The possible mechanism for the formation of Er5%:Gd2O3 nanorods is briefly discussed. [ABSTRACT FROM AUTHOR]

One dimensional uniform Sm3+ doped gadolinium hydroxide nanorods have been prepared via simple co- precipitation technique at 60 → temperature for 1 hour. The samples were calcinated at 750 → to obtain Sm3+ doped gadolinium oxide nanorods. The 1D nanorods were then subjected to different characterization techniques to ascertain its structural stability and its morphology were investigated using high-resolution transmission electron microscopy. Photoluminescence (PL) spectrophotometry was investigated and the obtained results were discussed in detail. [ABSTRACT FROM AUTHOR]

Nb2O5:Li (3 wt%) thin film of thickness 353 nm spray deposited onto ITO coated glass substrate at 350 °C is irradiated with 100 MeV O7+ ion at a fluence of 5×1012 ions/cm². X-ray diffraction shows that the pristine and irradiated films are polycrystalline with a tetragonal phase. Raman peaks suppressed upon irradiation imply large surface degradation which is also seen as a decrement in transparency in visible region to one half of the pristine film. Large red shift is observed in direct and indirect band gaps upon irradiation. Hall effect reveals slight increase in carrier concentration due to irradiation induced defects. [ABSTRACT FROM AUTHOR]

Neodymium doped gadolinium hydroxide [Nd:Gd(OH)3] nanorods were successfully synthesized at 60 °C through co-precipitation method. The dopant percentage was maintained at 5% and calcination was done at 750 °C temperature for 1 hour to form the respective neodymium doped gadolinium oxide [Nd:Gd2O3] nanorods. The as-formed and annealed products were investigated in detail by using powder X-ray diffraction (XRD) pattern, scanning electron microscopy (SEM) with an energy dispersive X-ray spectrum (EDX), high-resolution transmission electron microscopy (HRTEM) and photoluminescence (PL) spectrophotometry. [ABSTRACT FROM AUTHOR]

Nanocrystalline form of pure and Nd doped gadolinium hydroxide [Nd:Gd(OH(3] nanorods were successfully synthesized at 60 °C through simple co-precipitation method of Gd(NO3)3.6H2O and Nd(NO3)3.6H2O solutions with a specified pH, adjusted using NH3 as buffer solution. The dopant percentage was maintained at 5%. The as-synthesized Gd(OH)3 and Nd:Gd(OH(3 nanorods were annealed at 500 °C for 1 h to form the respective Gd2O3 and Nd:Gd2O3 nanorods. Powder X-ray diffraction (XRD) pattern, scanning electron microscopy with energy dispersive X-ray (SEM/EDX) and high-resolution transmission electron microscopy (HRTEM) analyses were used to characterize these as-synthesized [Gd(OH)3 and Nd:Gd(OH(3] and annealed [Gd2O3 and Nd:Gd2O3] nanorods. [ABSTRACT FROM AUTHOR]

The lithium (3 wt%) doped MoO3 thin film was prepared by spray deposition onto ITO substrate at 325 °C. The film of thickness 577 nm was irradiated with 200 MeV Ag15+ ion beams at a fluence of 5×1012 ions/cm2. The XRD pattern confirmed that the pristine film is polycrystalline with orthorhombic symmetry. Upon irradiation, the film turned amorphous. The sharp Raman peak in pristine film at 993 cm-1 is due to the terminal oxygen of α-MoO3 phase. Optical transparency of the film increased upon irradiation. Large red shift was observed in both direct and indirect band gaps. Electrical transport property study shows that the carrier concentration increased by one order for the irradiated film. [ABSTRACT FROM AUTHOR]

Nonlinear optical crystals of potassium acid phthalate (COOK C6H4 COOH)-KAP were grown from aqueous solution. Transparent crystals of size (21×17×4) mm3 with well defined morphology were grown from slow cooling techniques. The grown crystals were characterized by single crystal X-ray diffraction. The crystal structure of Potassium Acid Phthalate C8H5K+O4 was orthorhombic with the following unit-cell dimensions at 298(2) K; a = 9.5970(3) Å; b = 13.2869(5) Å; c = 6.4643(3) Å; α = 90°; β = 90°; γ = 90°; with a space group PCa21. Spectral analysis were carried out to investigate confirm its presence of various functional groups and to study the optical absorption properties. Third order nonliner studies have also been studied by Z-scan techniques. Nonlinear absorption and nonlinear refractive index were found out and the third order bulk susceptibility of compound was also estimated. The results have been discussed in detail. [ABSTRACT FROM AUTHOR]

Thin films of V2O5 were spray deposited at 450 °C on ITO coated glass substrates. The film with a thickness of 217 nm was irradiated with 100 MeV oxygen ion beam at a fluence of 5 × 1012 ions/cm2. Upon irradiation, the optical transparency of the film decreased from 90% to 40% and the band gaps estimated using Tauc relation showed red shift. Transport parameters were also measured. The induced modifications are mainly due to electronic energy loss and the results are discussed. [ABSTRACT FROM AUTHOR]

MoO3 thin films were deposited at 325 °C on ITO coated glass substrates by spray pyrolysis. The film was more textured along (102) plane. The bandgaps were estimated (Tauc relation) from absorption coefficient and film thickness (405 nm). The film had a reticulated fibrous surface morphology with 25 to 35% transparency. Photoluminescence (PL) emission is also observed. Cyclic voltametric measurement was also performed. The efficiency of the dye sensitized solar cell (DSSC) fabricated using the MoO3 film as a counter electrode is measured from the I-V curve. The results are discussed. [ABSTRACT FROM AUTHOR]