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Spinel type nano ferrite compound MgFe2O4 was synthesized through sol gel technique using metal nitrates as precursors. The phase composition, morphology and elemental analysis of magnesium ferrite (MgFe2O4) were performed by X-ray diffraction, fourier transform infrared, atomic force microscopy, energy dispersive x-ray and scanning electron microscopy, analyses. The sample's X-ray diffraction pattern verifies the existence of single phase material, with the size of its crystallites estimated to be 39.9 nm. Fourier transform infrared examination supported metal-oxygen vibrations corresponding to tetrahedral and octahedral sites, respectively. From scanning electron microscopy image, grain size obtained about 97.7 nm. Raman spectra of the sample shows five Raman active modes (A1g + Eg + 3F2g), which is compatible with the spinel structure. Magnetic measurement study at room temperature shows a hysteresis loop behaviour with a low saturation magnetization value, 27.192 emu g-1 and a small coercivity value. The optical band gap determined using UV-visible transmittance spectra. Additionally, X-ray photoelectron spectroscopy are used to confirm oxidation states and explore the chemical composition of the sample.

The synthesis and luminescence analysis of Tb3+-activated phosphors were reported. Y2SiO5 phosphors were synthesized by a modified solid-state reaction method with a variable doping concentration of Tb3+ ion (0.5–2.5 mol.%). As synthesized, the phosphors were characterized by X-ray diffraction (XRD) analysis. The XRD pattern confirmed the monoclinic structure of the prepared phosphor. Scanning electron microscopy and High-Resolution Transmission Electron Microscopy (HRTEM) studies revealed nearly uniform particle size distribution in the prepared phosphors. The photoluminescence excitation spectra of the Y2SiO5:Tb3+ (0.5–2.5 mol.%) phosphor displayed one broad, intense peak at 258–277 nm. When excited at the 258 nm wavelength, the phosphors showed emission peaks at 553 nm (5D4 → 7F5), 544 nm (5D4 → 7F5) and 489 nm (5D4 → 7F6). The 1931 CIE (x,y) chromaticity coordinates showed the distribution of the spectral region calculated from the photoluminescence emission spectra. The values of x = 0.25 and y = 0.46 were very close to light green emission. Therefore, the prepared phosphor is very useful for light-emitting diode (green component) applications. [ABSTRACT FROM AUTHOR]

The objective of the present work is to demonstrate the ability of the laser-induced breakdown spectroscopy (LIBS) technique for quick detection and quantification of rare earth elements (REEs) and radioactive elements in the black sands at selected locations of the Konkan coast (Goa) and Malabar coast (Kerala) in India. Several REEs such as Ce, Nd, Sm, Dy, Ho, Tm, Gd, and Th have been detected in the LIBS spectra. Calibration-free LIBS method has been used to calculate the concentration of REEs and radioactive elements. The experimental result shows that the concentration of REEs such as Sm, Dy, Ho, and radioactive element Th is maximum in the sands collected from Thiruvananthapuram (Kerala) beach and minimum in the Baga (Goa) beach. The reliability of the results (qualitative and quantitative) obtained by the LIBS method has been examined by other spectroscopic techniques like XRF and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and found to be in close agreement. The multivariate approach (principal component analysis) has been applied to discern the samples based on their spectral data. Photoacoustic spectroscopy and XRD technique are used to detect compounds/minerals of REEs. The relative hardness, degree of crystallinity (DOC), and crystallite size have been calculated. [ABSTRACT FROM AUTHOR]

Y2Sr3B4O12 phosphors doped with europium ions were synthesized by a modified conventional solid-state reaction method. Characterizations of the prepared samples, viz., X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), and Commission Internationale de I'Eclairage were studied. The XRD analysis confirmed the formation of mixed phase due to polyborate and has a hexagonal crystalline yttrium orthoborate phosphor. SEM images showed the irregular morphology of the sample. The grain size distribution was broad and the average size was found to range from 2 μm to 100 nm. PL measurements showed excitation and emission characteristics of the prepared phosphor with different concentrations of the doping ion. From the emission spectra, it was clearly observed that the emission intensity of the magnetic dipole was higher than that of electric dipole transition owing to the Eu3+ ions occupying a higher symmetry site in the Y2Sr3B4O12 host. The intensity of PL increased with increasing concentration of the doping ion up to 2.0 mol.%; after that, the PL intensity decreased owing to the concentration-quenching phenomenon. The results indicated that Y2Sr3B4O12:Eu3+ phosphors can be selected as a potential candidate for solar cell/photovoltaic application. [ABSTRACT FROM AUTHOR]

We report on the structure and diffusion behaviour of the various constituent molecules in ionic liquid (IL) mixtures under confinement in nanoporous glasses. X-Ray diffraction measurements indicate that the ions adopt a lamellar arrangement under confinement. Furthermore, using selective deuteration in combination with high resolution neutron spectroscopy reveals how the dynamics and the activation energy of the IL is affected by different confinement conditions (pore sizes 50 Å and 135 Å) and different temperatures (265 and 318 K). With different deuteration schemes we could separate the different motions of acetate and water. The confinement leads to distortions of the domains, which gives more room for diffusion. In the smaller pores, the stronger distortion gives even more room such that the hydrogen bonds between acetate and water seem to be even stronger than in bulk and weaker confinement. The results are discussed in the context of previous measurements on dry samples.

We present the electrospinning preparation and investigation of metal oxides TiO2 (T), ZnO (Z) and TiO2/ZnO (TZ) composite nanofibers. For the fabrication of TZ composite nanofibers, different proportions of TiO2/ZnO solutions (1:1, 1:2, 2:1 and 1:3) are preferred. X-ray diffraction (XRD) pattern of sample ‘T’ exhibited the mixed anatase and rutile phases while the wurtzite phase is examined in the sample ‘Z’. The field-emission scanning electron microscopy (FESEM) study evidenced the preparation of continuous and randomly oriented nanofibers whereas the transmission electron microscopy (TEM) investigation endorsed the cylindrical morphology of the TZ13-sample with mean diameter of 230 nm. The lattice d-spacing is estimated to be 0.289 nm corresponding to the plane (100) of the hexagonal wurtzite ZnO while selected-area electron diffraction (SAED) analysis endorsed the polycrystalline nature of the TZ13 composite nanofibers. Finally, photodegradation of the Eriochrome black T dye was performed and the catalyst TZ13 showed about 85% photodegradation in 90 min as compared to TZ11, TZ12 and TZ21. This boosted photocatalytic activity is ascribed to the synergetic effect of the TiO2/ZnO composite nanofibers with their distinct morphology.

Low-energy nuclear reactions are known to be extremely dependent on the local crystal structure and crystal defects of the deuterated samples. This has a strong influence on both hydrogen diffusion and the effective electron mass. The latter determines the strength of the local electron-screening effect and can change the deuteron–deuteron reaction rates at very low energies by many orders of magnitude. In the present study, zirconium samples were exposed to various conditions and energies of deuteron beams using the unique accelerator system with ultra-high vacuum, installed in the eLBRUS laboratory at the University of Szczecin. Irradiated and virgin samples were investigated by means of the X-ray diffraction (XRD) and positron annihilation spectroscopy (PAS). While the first method delivers information about changes of crystal lattice parameters and possible production of hydrides accompanying the formation of dislocations that are produced during irradiation of the samples, the second one can determine the depth distribution of crystal defects, being especially sensitive to vacancies. The studied Zr samples were also implanted by carbon and oxygen ions in order to simulate the real situation taking place in nuclear reaction experiments and to investigate their influence on the kinetic of produced vacancies. The observed enhancement of the electron-screening effect in the deuteron fusion reaction at very low energies could be explained by formation of a high number of vacancies during the deuteron irradiation of samples. Possible carbon and oxygen impurities can affect this process in various ways by changing the depth distribution of vacancies and their diffusion, but they play only a minor role in the strength of the electron-screening effect. [ABSTRACT FROM AUTHOR]

O,O'-Diethyl-S-(N-phthalimidomethyl) dithiophosphate was synthesized and characterized by different spectroscopic methods (UV, IR, 1H, 13C, 31P, and 15N NMR) as well as DTA, TGA, DSC, and ESI techniques and single crystal X-ray diffraction. The compound exhibits fluorescence behavior and can serve as an antimicrobial agent. The crystal structure of O,O′-diethyl-S-(N-phthalimidomethyl) dithiophosphate displays the monodentate nature of the alkyl dithiophosphate moiety. [ABSTRACT FROM AUTHOR]

This article describes the synthesis of 1-(((4-nitrophenyl)imino)methyl)naphthalen-2-ol Schiff base (H4NA) and its organyltellurium(IV) complexes and characterization via numerous physical and spectral techniques like MS, FT-IR, UV–Vis, 1H-NMR, 13C-NMR, EDX, Powder XRD, TG-DTG and molar conductance measurements. The characterization results indicate that the Schiff base is bidentate in nature and the complexes adopt distorted square pyramidal geometry. In vitro antioxidant and antimicrobial evaluations indicate that the biological efficacy of the Schiff base was enhanced on chelation. Complexes 4b, 4d and 4f exhibited the highest scavenging efficacy with the lowest IC50 value. While, the antimicrobial examination indicated the more inhibitory property of 4b, 4c and 4e complexes against all the screened microbial organisms. The molecular docking analysis of compounds on the catalytic site of Pseudomonas aeruginosa (2UV0) reveals favorable interactions and supports the good biological response against 2UV0. Further, to support the experimental findings, the molecules were theoretically examined using quantum chemical calculations. The FMO studies was performed on B3LYP/6-31G*, to validate the increased bioactivity of the complexes as compared to the Schiff base. MESP of the compounds identified their highly reactive regions. The hyper-conjugative interactions and second-order perturbation interaction energy of the compounds have been calculated with the help of NBO analysis. The anticipated ADMET characteristics of the compounds were consistent with Lipinski's and other restrictive rules indicating that they can function as effective inhibitors. [ABSTRACT FROM AUTHOR]

In this paper, we have synthesized CoFe2O4 nanoparticles by ultrasonication-assisted sol–gel technique at a lower temperature (600 °C), mainly to comprehend the impact of cation redistribution at tetrahedral and octahedral sites on structural, optical, and magnetic properties. The analysis of the synthesized compounds by Rietveld's refined X-ray diffraction pattern reveals that the synthesized compound crystallizes in a cubic structure with Fd-3m space group. The obtained crystallite size is found to be 12.37 nm estimated from Hall–Williamson plot. The FE-SEM results depicted the formation of particle in spherical shape and flake-like grain structure. Moreover, the ultra-violet–visible (UV–Vis) spectroscopic study revealed the semiconductor nature of synthesized CoFe2O4 compound with direct bandgaps of around 1.76 eV. In the magnetization study, the saturation magnetization and remanence field are shown in decreasing nature whereas the coercivity value increases from room temperature to 5 K. The acquired variation between 5 and 300 K is because of the interaction between the distribution of cations at different tetrahedral and octahedral sites. The cationic redistribution and calcination temperature is responsible forthe significant change in optical energy bandgap and magnetic properties of CoFe2O4 nanoparticles. The improved magnetic properties and significant change in optical energy bandgap due to cationic redistribution and calcination temperature are advancements for the scientific community. [ABSTRACT FROM AUTHOR]

This work presents the influence of substrate temperature (${T}_{\text{sub}}$) and post-sulfurization on compositional, structural, electrical, and optical properties of dual-ion beam sputtering (DIBS)-grown Cu2(Sn,Ge)(S,Se)3 (CTGSSe) thin films grown on a soda-lime glass (SLG) substrate using a single target. Post-sulfurization of CTGSSe thin films is carried out in a quartz tube chemical vapor deposition (CVD) system. X-ray diffraction (XRD) analysis reveals that the crystal structure of CTGSSe thin films is preferentially tetragonal with (112) and (204) lattice planes at $2\theta $ values of 27.3° and 47.3°, respectively. Field-emission scanning electron microscopy (SEM) has emphasized that the high ${T}_{\text{sub}}$ growth resulted in a larger grain size of 87 nm and better thin-film morphology. Spectroscopic ellipsometry (SE) analysis shows the bandgap values of 1.46–1.62 eV by varying ${T}_{\text{sub}}$ from room temperature (RT) to 300 °C. Furthermore, the bandgap widens from 1.56 to 1.64 eV in the CTGSSe thin films due to post-sulfurization. [ABSTRACT FROM AUTHOR]

In the present work, Ni0.6Cd0.4DyxFe2-xO4 (x = 0.0, 0.05, 0.10, 0.15, 0.20) nanoparticles (NPs) were synthesized by using sol–gel method. X-ray diffraction (XRD) patterns confirmed that the pure and dysprosium substituted Ni–Cd ferrites are in single-phase spinel structures, while a trace of DyFeO3 appears as a minor phase for higher concentrations (x = 0.10, 0.15 and 0.20). The Debye–Scherrer's method and Williamson–Hall (W-H) method were used to evaluate the crystallite sizes and lattice strain. Scanning electron microscope (SEM) images show that reduction of grain size with Dy3+ content. Elemental composition features of samples were examined by Energy-dispersive X-ray spectroscopy (EDS). The average particles size estimated from transmission electron microscopy (TEM) analysis is in good agreement with results obtained from XRD. The results showed that saturation magnetization (Ms) decreases and coercivity (Hc) increases with an increase in Dy3+ concentrations. The dielectric constant was found to decrease with increasing Dy content in Ni–Cd ferrites. [ABSTRACT FROM AUTHOR]

In the present report, thermally stimulated luminescence (TSL) of quartz and limestone samples irradiated with β and γ-rays has been investigated. Herein the formation of trap depths and calculation of kinetic parameters of β and γ - irradiated quartz and limestone samples were studied through thermoluminescence (TL) glow curve analyses. The quartz and limestone samples were collected from various sites of Chhattisgarh (Patharia and Dalli-Rajhara mines). The collected raw samples were annealed at 400 °C. The phase formation of collected samples is confirmed by X-ray diffraction studies. The grain sizes of the samples are determined by using Debye-Scherrer formula. TL glow curves of the collected samples were recorded for various doses of β and γ-rays. Kinetic parameters such as order of kinetics frequency factor and trap depth were calculated by employing CGCD methods. A comparative study on the TL properties of the geological materials under β and γ-irradiation was done. The trap model analysis was executed to determine the nature of traps responsible for dominant TL peaks of β and γ-irradiated limestone and quartz samples. [ABSTRACT FROM AUTHOR]

In the present study, fermentative production of bacterial nanocellulose (BNC) by using Komagataeibacter xylinus strain SGP8 and characterization of nanocellulose is presented. The bacterium was able to produce 1.82 g L−1 of cellulose in the form of pellicle in standard Hestrin-Schramn (HS) medium. The morpho-structural characterization of the BNC using scanning electron microscopy (SEM) and X-ray diffraction (XRD) studies, respectively revealed nanofibrillar structure and high crystallinity index (~86%). The thermogravimetric analysis (TGA) showed the stability of BNC up to 280 °C, further rise in temperature to 350 °C results in depolymerization of the sample. In order to show the applicability of produced BNC, it was modified first using calcite (CaCO3) and thereafter characterized using SEM, XRD, FTIR, and TGA studies. The BNC-CaCO3 composites as a sorbent resulted in >99% removal of initial 10 mg L−1 of Cd (II) at pH 5, 7 and 9 after 12 h of treatment. Moreover, the composite was also found to be competent in removing high concentrations of Cd (25 and 50 mg L−1) from the solution (69–70%). Overall, the above results suggest that cellulose produced by K. xylinus strain SGP8 showed excellent material properties, and modified BNC (BNC-CaCO3 composite) could effectively be used for remediation of toxic levels of Cd from the contaminated system. [ABSTRACT FROM AUTHOR]

Cadmium-substituted manganese ferrite nanoparticles with the general formula Mn1‒xCdxFe2O4(x = 0.0, 0.2, 0.4, 0.6, 0.8) were synthesised by the citrate‒gel auto combustion method. X-ray diffraction patterns revealed formation of a cubic phase spinel structure with F d 3 ˉ m space group. FT-IR confirms stretching vibration of tetrahedral and octahedral interstitial sites in the spinel lattice. Microstructural features observed by scanning electron microscopy (SEM) demonstrate that agglomerated particles were formed with an increase in average grain size according to Cd2+ content. Elemental composition features and particle size of samples were examined by energy dispersive spectroscopy (EDX) and Transmission electron microscopy (TEM). The magnetic properties characterised by the highly sensitive magnetometer system (SQUID VSM) at room temperature revealed ferromagnetism in all the samples. The values of dielectric permittivity ε ′ and tangent loss ( tan δ ) decreased exponentially at low frequencies and were in accordance with the Maxwell–Wagner model and Koop's theory. [ABSTRACT FROM AUTHOR]

Mesoporous nanoparticles have a larger surface area and therefore, suitable for dye‐sensitised solar cells and photocatalytic applications. This Letter presents the analysis of solvothermal derived as‐prepared TiO2 and doped TiO2 nanocrystals by utilising acetone as the solvent. The as‐prepared and doped TiO2 nanoparticles endorsed the presence of anatase phase along with the slightly deviated diffraction peaks with the reduced crystallite size as a result of doping. Surface morphology analyses evidenced the mesoporous microspheres of nanoparticles, whereas the stoichiometry study exhibited the elementary peaks in the as‐prepared and doped samples. The estimated optical bandgaps are found to be 2.68, 2.92, 2.48 and 2.88 eV in accordance with the doped TiO2 with copper, tin, barium and zinc–magnesium as compared to 3.16 eV of TiO2. Doped samples evidenced the enhanced scattering capability, whereas tin and zinc–magnesium co‐doped samples demonstrated the highest diffuse reflectance in a broad wavelength range from 550 to 800 nm. [ABSTRACT FROM AUTHOR]

This Letter reports the synthesis of nanoceramic composite ZnAl2O4TiO2 by using a cost‐effective and straight forward sol–gel route. X‐ray diffraction (XRD) showed the ZnAl2O4 cubic structure along with the mixed anatase‐ and rutile‐phases of TiO2. Rietveld refinement is performed using XRD pattern to study the structural parameters. Raman investigation endorsed the corresponding vibration peaks of TiO2 and ZnO. Field‐emission scanning electron microscopy evidenced the agglomerated spherical nanoparticles. Energy‐dispersive spectroscopy analysis demonstrated the elementary peaks of Zn, Al, and Ti at 4.5, 1.5, and 1 eV, respectively. LCR measurement revealed the decreased dielectric permittivity with the rise in frequency and temperature. This dielectric characteristic is attributed to the dipole movement of the charge carriers. Furthermore, the authors present the investigation of the conductivity and impedance of the prepared dielectric ceramic material. [ABSTRACT FROM AUTHOR]

This Letter presents the electrodeposition of zinc oxide (ZnO) nanostructures by varying the negative potential and investigation of structural, optical, and morphological characteristics. UV–vis spectroscopy investigation showed the redshift of the absorption peak with the increased negative potential. Using Tauc relation, the optical bandgap values estimated to be 3.09, 2.97, 2.93, 2.91, 2.90, and 2.84 eV corresponding to the samples prepared at potential −0.5, −0.7, −0.9, −1.1, −1.3 and −1.5 V. Fluorescence spectra exhibited the UV emission band at wavelength 392 nm along with a peak at 650 nm corresponds to the second‐order nature of ZnO. Fourier‐transform infrared spectroscopy analysis confirmed the various vibration modes at 403, 493, and 702 cm−1 originated by the ZnO nanostructures. X‐ray diffraction pattern revealed the hexagonal wurtzite phase of ZnO. Scanning electron microscopy investigation evidenced the distinct morphology of ZnO with the increased negative potential; however, the dense and perpendicularly oriented ZnO nanorods are prepared at highest negative potential as compared to rice grain‐like ZnO structure prepared at least negative potential. Furthermore, the prepared nanostructures are used as dye‐sensitised solar cells (DSSCs) photoanodes, while the DSSC‐Z6 showed the increased cell efficiency up to 1.2%, due to the aligned growth of the ZnO nanorods. [ABSTRACT FROM AUTHOR]

Lead (Pb) ions are a major concern to the environment and human health as they are contemplated cumulative poisons. In this study, facile synthesis of magnetic iron oxide–tea waste nanocomposite is reported for adsorptive removal of lead ions from aqueous solutions and easy magnetic separation of the adsorbent afterwards. The samples were characterised by scanning electron microscopy, Fourier transform‐infrared spectroscopy, X‐ray diffraction, and Braunner–Emmet–Teller nitrogen adsorption study. Adsorptive removal of Pb(II) ions from aqueous solution was followed by ultraviolet–visible (UV–Vis) spectrophotometry. About 95% Pb(II) ion removal is achieved with the magnetic tea waste within 10 min. A coefficient of regression R2 ≃ 0.99 and adsorption density of 18.83 mg g−1 was found when Pb(II) ions were removed from aqueous solution using magnetic tea waste. The removal of Pb(II) ions follows the pseudo‐second‐order rate kinetics. External mass transfer principally regulates the rate‐limiting phenomena of adsorption of Pb(II) ions on iron oxide–tea waste surface. The results strongly imply that magnetic tea waste has promising potential as an economic and excellent adsorbent for the removal of Pb(II) from water. [ABSTRACT FROM AUTHOR]

This review includes research papers on different method of preparation of rare earth activated Sr2SiO4 phosphors and its luminescence studies. Here in Sr2SiO4 has attracted great interest due to its special structure features, excellent physical and chemical stability. Besides, it absorbs ultraviolet radiation and emits white light when activated by different rare earth ions. Different synthesis techniques were compared and it is found that sol–gel synthesis technique is best for preparation of rare earth activated Sr2SiO4 phosphors. Literature related to characterization techniques such as X-ray diffraction techniques, scanning electron microscopy, transmission electron microscopy and other studies are also compared. Photoluminescence studies for white light emitting diode of various rare earth phosphors are compared with Sr2SiO4 phosphor reported in this review. Also some luminescence techniques such as thermoluminescence glow curve analysis and some spectroscopic parameters are also compared. The review end with some important conclusion related to rare earth activated Sr2SiO4 phosphors with proper justifications. [ABSTRACT FROM AUTHOR]

Herein the manuscript reports kinetics and Thermoluminescence (TL) glow curve analysis of UV-, β- and γ-irradiated natural limestone samples collected from Chunkatta mines of Chhattisgarh basin. The collected samples were annealed at 100°C for 1 h for preheat treatment before irradiation after that the samples were irradiated by UV, β and γ, respectively. After irradiation the 1 mg weigh samples perform for TL glow curve analysis. Collected limestone was characterized by X-ray diffraction analysis technique and crystallite size was calculated using Scherer’s formula. UV-irradiated sample shows the high-temperature peak centered at 250°C, for β-irradiated sample showed well resolved broad TL glow curve at 404 K which is fitted using computerized glow curve deconvolution (CGCD) technique. Similarly, for γ-irradiation the well resolved three distinct peaks at 209, 288 and 388°C showed the formation of deep trapping for γ-irradiation. Dose rate effect for UV- and γ-irradiation reported in details as well as the trap formation were described by trap depth model. Kinetic parameters for UV-, β- and γ-irradiation were calculated using peak shape method by CGCD technique. The study was determined the trap level formation and application related to TL dose response in collected limestone sample. [ABSTRACT FROM PUBLISHER]

This paper reports on the thermoluminescence (TL) properties of Eu doped in two different host matrix phosphors (YO and YBO). The phosphors were prepared by a high temperature solid state reaction method. The method is suitable for a large scale production. The samples were characterized by X-ray diffraction and Rietveld refinement. The different concentration of Eu samples were also examined by TL glow curve analysis for UV, β and γ irradiation. The YO samples showed well resolved broad peaks that covered the temperature range from 50 to 350 °C and the peak temperature was found at 157 °C for the γ irradiation. For the UV irradiated samples a well resolved peak at 121 °C was found for the YO:Eu doped phosphors. The β irradiated samples showed a resolved peak at 182 °C. A different behaviour was observed for the YBO:Eu doped phosphors which showed both higher temperature peaks and lower temperature peaks for UV, β and γ irradiation. Here UV irradiated sample showed the formation of shallow trap (surface trapping) and the γ irradiated sample showed the formation of deep trapping. The estimation of the trap formation was evaluated by the calculation of the trapping parameters. The trapping parameters such as activation energy, order of kinetics and frequency factor were calculated by the peak shape method using the computerized glow curve deconvolution technique. Here most of the peak showed second order of kinetics. The effect of γ, β and UV dose exposure on the TL studies was also examined and it showed a linear response with dose which indicated that the samples might be useful for TL dosimetry. The possible mechanics and information about traps formation are presented in detail. [ABSTRACT FROM AUTHOR]

We present a Raman study of Fe3O4 (100) thin films across the Verwey transition in the temperature range of 85–300 K. These films are epitaxially grown on MgO (100) substrate by pulsed laser deposition technique. X-ray diffraction and low temperature resistivity measurements reveal that these films exhibit high structural order and perfect stoichiometry with Verwey transition at 121 K. The frequency of different Raman modes [A1g and T2g(2)] changes abruptly around the Verwey transition temperature (TV). Below TV we observe a splitting in T2g(3) mode. Using Allen’s formula [Solid State Commun. 14, 937 (1974)] the strength of the electron-phonon coupling (λ) is estimated from the observed line shape parameters, and our estimates show that in epitaxially grown Fe3O4 thin films strong electron-phonon coupling is present. This coupling parameter is larger for T2g(3) mode as compared with that of A1g and T2g(2) modes. It is also observed that the coupling parameter corresponding to A1g mode remains invariant going from bulk single crystal to thin film while that of T2g(2) and T2g(3) modes are almost doubled. An attempt has been made to correlate the observed behavior with the presence of antiphase boundary in epitaxial thin films. [ABSTRACT FROM AUTHOR]

• XRD, CPMAS, NMR, FTIR,TGA Characterization of different waste PE and PP. • Pyrolytic conversion of waste plastics and degradation pathway. • Composition and performance analysis of pyrolytic liquid from waste plastics. • Correlation between composition of plastics and pyrolysis liquid. • Recommendation for optimal use of different types of plastics for management. Thermal pyrolysis of polyolefins has been proposed as one of the possible ways to obtain petroleum-derived products (fuels and chemicals) from waste plastics however, there is a lack of deep understanding of the correlation between the structure and composition of polyolefin feedstock with pyrolysis oil. Pyrolysis oil has been obtained from polyethylene (PE) and polypropylene (PP) in a tubular reactor at 500 °C. TGA-DTG, 13C CP-MAS NMR, FTIR, and XRD were used to analyze the polyolefin (PE and PP) feedstock, while pyrolysis oil was characterized by GC–MS, FTIR, and 1H NMR techniques. The pyrolysis oil from virgin and waste PP yielded branched alphaolefins and cycloparaffins, while virgin and waste PE produce linear alpha olefins and linear paraffins. Mixed waste plastic (MWP) produces major amount of linear paraffins and linear alpha olefins, indicating the overall trend of branching in polyolefins (PE and PP) from feedstock to product oil is retained after pyrolysis. The alpha olefins can be used as chemical intermediates, while 2,4 dimethyl 1-heptene from PP can be used as a fine chemical precursor better feedstock for gasoline. Segregation of waste plastics is challenging task in real life but source segregation and selective collection of waste plastics from various sources can produce useful products like high octane gasoline range hydrocarbons and high-value chemicals. [ABSTRACT FROM AUTHOR]

• Six organyltellurium(IV) complexes were prepared and characterized. • The newly prepared complexes displayed improved antimicrobial and antioxidant activities than the Schiff base. • Molecular docking studies of the compounds were executed to analyze their binding affinity with P. aeruginosa (2UV0). • DFT, MESP and NBO study of the Schiff base and complexes using B3LYP/6-31G* level of theory were executed. • ADMET properties were studied. In this article, the synthesis of 1-(((2-nitrophenyl)imino)methyl)naphthalen-2-ol (H2NA) Schiff base and its organyltellurium(IV) complexes were carried out and investigated via numerous spectral and physical methods like FT-IR, MS, 1HNMR , 13CNMR , UV–Vis, EDX, Powder XRD, TG-DTG and molar conductance measurements. The spectroscopic characterization results elucidate the bidentate nature of the Schiff base and distorted square pyramidal geometry of the complexes. Further, the compounds were theoretically investigated via quantum chemical computations to justify the experimental results. The thermal analysis results indicate the dehydrated nature of the complexes. In vitro biological evaluations (antioxidant and antimicrobial) indicates that the biological efficiency of the Schiff base was enhanced on complex formation. The antioxidant activity revealed the highest scavenging ability of the 3a, 3b and 3d complexes among the synthesized compounds with lowest IC 50 value. While, the antimicrobial examination indicates the more inhibition property of 3c, 3e and 3f complexes against all the tested microbes. The in silico , molecular docking simulation of the compounds on the active site of Pseudomonas aeruginosa (2UV0) indicates promising interactions and advocates the good biological response against 2UV0. The FMO studies also supports the more bioactivity of complexes as compared to Schiff base which carried out on B3LYP/6–31G*. MESP of the compounds displayed their most reactive regions. The hyper-conjugative interactions and stabilization energy of the compounds have been estimated via NBO analysis. The predicted ADMET profiles of the compounds align with Lipinski's and other restrictive rules indicating their potential to act as effective inhibitors. [Display omitted] [ABSTRACT FROM AUTHOR]

• Transition metal doped CeO 2 Nps synthesized by co-precipitation method. • Rietveld refinements of high-quality powder XRD show good convergences. • Band gap tunability was seen with transition metal doping in CeO 2 Nps. • Transition metal doping influenced the photoluminescence and optical properties. In this study, pure and transition metal doped (TM = Fe, Co, and Ni), cerium oxide nanoparticles have been synthesized by the co-precipitation techniques. Rietveld refined X-ray diffraction (XRD) patterns affirm the monophase nature with cubic symmetry having an Fm3m space group and crystalline size varies in the range of 9–14 nm calculated by Debye Sherer's formulation. The morphological study has been done by scanning electron microscope (SEM) technique anticipated that agglomerated grains symmetry with the typical grain size distribution varies from 45 to 52 nm. The effect of transition metal doping on bending/stretching vibrational modes has been effectively investigated by FTIR analysis. The strong absorbance edge was seen in the UV region and shifted in the red region with the doping of transition metal ions. The tauc's plot of UV–vis absorption uncovers the bandgap decreased from 2.87 eV to 2.42 eV on transition metal doping. The photoluminescence spectroscopy (PL) technique was used to investigate the presence of oxygen vacancies and intrinsic defects in the host CeO 2 lattice when doped with transition metal ions. These imperfections induce the lattice disorder and shift in the energy bandgap from the UV to the visible region of the spectrum by affecting its electronic transitions. The CIE chromaticity coordinates of pure and transition metal doped compounds observed in the blue region might be applicable in display devices. In this manner, these materials can be fascinating for tuneable electrical and optical devices. [ABSTRACT FROM AUTHOR]

A cost effective and environmental friendly sol-gel autocombustion technique has been used to synthesize spinel ferrite nanoparticles of NixZn1-xFe2O4 (x = 0.0, 0.5 and 1.0). They were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and Energy dispersive X-ray spectroscopy (EDX). While their magnetic properties have been measured at room temperature using a Magnetic Properties Measurement System (MPMS) quantum design magnetometer, the LCR meter (PSM 1735, NumetriQ 4th Ltd U.K.) has been used to study their dielectric properties with variable frequency in the range, 1 Hz-5 MHz. The XRD analysis suggests the presence of cubic spinel structure of ferrites with an average crystallite size of 45-79 nm. The dielectric constant and loss tangent of the samples show a normal dielectric behavior. The variation of dielectric behavior with the frequency is due to the Maxwell-Wagner type interfacial polarization and hopping of electrons between the Fe2+ and Fe3+ ions. The magnetic studies reveal that addition of Zn2+ drastically affects the magnetic properties. [ABSTRACT FROM AUTHOR]

Abstract Al x Cu 0.5 FeNiTi high entropy alloy coating is synthesized by premixed high purity Cu, Fe, Ni and Ti powders on AA1050 aluminium substrate by laser surface alloying, with the aim to improve microhardness and erosion rate. Phase constituents, microstructure and microhardness were investigated using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Vickers Microhardness tester, respectively. The erosion behavior of Al x Cu 0.5 FeNiTi coating is checked using an air jet erosion setup. SEM images show presence of three regions. Percentage compositions of these regions are evaluated using Energy Dispersive Spectroscopy. XRD analysis of Al x Cu 0.5 FeNiTi coating confirmed that these regions are a mixture of disordered BCC and two FCC solid solution phases. The microhardness of the Al x Cu 0.5 FeNiTi HEA is 18 times that of the AA1050 aluminium substrate. Results show that Al x Cu 0.5 FeNiTi HEA coating has improved erosion resistance. Highlights • High entropy alloys possess desirable properties for applications in advanced industries. • Al x Cu 0.5 FeNiTi is alloyed on aluminium AA1050 substrate using fiber laser. • Alloyed bead metallurgical and mechanical characteristics have been analyzed. • Formation of three phase system is confirmed by XRD analysis. • An improvement in microhardness and erosion resistance is achieved. [ABSTRACT FROM AUTHOR]

In the present study attempt was made to synthesize iron nanoparticles in the presence of alumina (Al-nZVI) by sodium borohydride reduction process. The composite adsorbent has been characterized using various analytical techniques such as scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction and transmission electron microscopy which showed that iron nanoparticles were partially dispersed on alumina surface, with their diameter being in the range 40-100 nm. The batch adsorption experiments were carried out to study the effect of different parameters. The maximum removal of fluoride was obtained at optimal condition of pH 5.0 and dose = 1.8 g/L and was observed to be 94% with contact time of 60 min at 40 °C and initial concentration of 2 mg/L. The adsorption data fitted that pseudo second order kinetics and followed Langmuir isotherm model with maximum adsorption capacity of 10.06 mg/g. Thermodynamic study revealed exothermic nature of adsorption. [ABSTRACT FROM AUTHOR]

Elliptic-type integral plays a major role in the study of different problems of physics and technology including fracture mechanics. Many papers have been written for various families of elliptic-type integrals. Due to their applications here, we are presenting an organized study of certain generalized family of incomplete elliptic integral. The obtained results are basic in nature have various generalizations. While using the fractional integral operator of Riemann-Liouville type, we found several obvious hyper geometric representations. Which are further used to originate many definite integrals relating to their modules and amplitude of elliptic type generalized incomplete integrals. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Electrospinning fabrication of TiO 2 nanofibers via process parameters are presented. • XRD study showed the presence of mixed anatase and rutile phases. • TG/DTA investigation performed to study the characteristic peaks of TiO 2 /PVP mat. • FTIR investigation endorsed the characteristic peak of Ti O Ti bond. • The optimal process parameters led to preparation of thin TiO 2 nanofibers. Abstract This paper reports the electrospinning fabrication and characterization of TiO 2 nanofibers. Various electrospinning process parameters such as applied voltage, distance tip-collector, solution flow rate and polymer (PVP) concentration are studied. The prepared nanofibers were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), thermogravimetric-differential thermal analysis (TG-DTA) and Fourier transform infrared spectroscopy (FTIR). XRD pattern of TiO 2 nanofibers evidenced the presence of mixed phases of anatase and rutile. TG/DTA investigation showed the characteristic peaks corresponding to the heating behavior of TiO 2 -PVP mat. FTIR investigation endorsed a vibration peak at 660 cm−1 associated with the characteristic Ti O Ti bond. With the optimized process parameters, TiO 2 nanofibers diameter was found to be reduced to 74 nm as compared to the first sample prepared with the diameter of 343 nm. Furthermore, these nanofibers were employed as the photoanode material for the preparation of dye-sensitized solar cell (DSSC) and photovoltaic study is evaluated. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Calotropis procera assisted green route followed for nanoparticle formation. • JCPDS No. 65-3103 confirms Co 3 O 4 nanostructure. • TEM analysis show spherical nanoparticles of average particle size 9.97 nm. • Non-toxic behaviour towards environment. Abstract A novel green synthesis of cobalt oxide (Co 3 O 4) nanoparticles using latex of Calotropis procera via simple precipitation method at room temperature was investigated. An extensive characterization of the product was carried out using X-ray diffractometry (XRD), Differential scanning calorimetry (DSC), Transmission electron microscopy (TEM), Energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR) and UV–Visible spectroscopy. The results of the characterization confirmed that the synthesized nanomaterial is highly dispersed. TEM analysis revealed that the nano particles are having an average size around 10 nm. The eco-toxic investigation suggested that the particles are non-toxic and safe towards the environment. This green strategy proves to be an effective, fast, simple and cost-effective approach for the synthesis of Co 3 O 4 nanoparticles for various applications. [ABSTRACT FROM AUTHOR]

A novel Mn(III) complex with γ-diketone having general formula [Mn(hdo)3], where hdo = hexane-2,5-dione ligand, has been synthesized and characterized using UV-vis, FT-IR, ESI-mass and EPR spectra, elemental analysis, powder X-ray diffraction, SEM, and magnetic susceptibility measurements. The X-ray diffraction studies reveal that it has monoclinic lattice system with C2/C space group and the unit cell dimensions are a = 9.92245 Å, b = 10.50696 Å, and c = 9.80835 Å. The particle size of this complex has been found to be 32.1 nm. The complex was evaluated for its antifungal activity against Aspergillus flavus, Aspergillus niger, and Aspergillus terreus fungal species. The results indicate that the minimum inhibitory concentration of the synthesized complex was 8 ppm for A. niger while for A. flavus and A. terreus it was 6 ppm. β-Diketone Mn(III) complexes inhibit the fungal growth only partially. This communication is the first report of transformation of a keto-group to an ester group catalyzed by a metal complex. [ABSTRACT FROM AUTHOR]

Magnetite powder was synthesized via chemical co-precipitation method using FeCl3 · 6H2O and FeCl2 · 4H2O as salts and ammonium hydroxide (25% NH4OH) solution as precipitating agent. The phases, composition and morphology of the magnetite was characterized by X-ray diffraction (XRD), micro laser Raman spectroscopy and scanning electron microscopy–energy dispersive X-ray spectroscopy. The XRD and Raman studies confirmed the formation of magnetite phase only. The results showed that the particles were properly crystallized with no other impurity. Very fine and non-uniform powder sizes were observed even after sieving operation. The magnetite particles were also characterized after sintering the powder at 1100°C, grinding and sieving. The resultant powder size in the range of 105–125 µm was obtained. After sintering, magnetite peaks got sharpened due to increase in the crystallite size. Raman peaks even at a higher laser power were observed for magnetite that were absent before sintering. Hematite peaks observed for the un-sintered powder at higher laser power was attributed to oxidation by laser radiation/heat. Efficiency of the co-precipitation process (before sintering) was established to be ∼85%. [ABSTRACT FROM AUTHOR]

Nanocrystalline TiO 2 particles were prepared to study the calcination temperature dependent phase transformation. X-ray diffraction (XRD) patterns showed the strong Bragg peaks correspond to anatase (1 0 1) and rutile (1 1 0) phases with their crystallite size 12 and 49 nm for the samples T1 and T2 calcined at 450 and 700 °C respectively. Raman spectroscopy investigation showed the phase transformation with the dominating rutile peaks from the pure-anatase phase. By UV–vis absorption spectroscopy, the strong ultraviolet-light absorption below 400 nm was observed. Using Kubelka-Munk function, the estimated band gap values were found to be 3.38 and 3.03 eV. The transmission scanning microscopy (TEM) images exhibited the slightly agglomerated nanoparticles while the selected area diffraction (SAED) patterns endorsed the polycrystalline nature. [ABSTRACT FROM AUTHOR]

SrAl2O4Eu2+ green-light emitting powder phosphor was prepared within a few minutes at furnace temperature as low as 550 °C by using combustion method. The prepared powder was characterized by X-ray diffraction, scanning electron microscopy and Fourier-transform infrared spectrometry. Several ESR lines are exhibited by the phosphor, and some are seen in the low field region apart from lines in the g ~ 2.0 region. Crystal fields that were relatively strong arose from distortions close to the Eu2+ ion lead to lines in the low field region. The photoluminescence of Eu2+-activated SrAl2O4 shows a green-emission dominant peak around 514 nm, which can be attributed to the 4f65d1 → 4f7 transition of Eu2+ ions from the synthesized phosphor particles at an excitation wavelength of 345 nm. [ABSTRACT FROM AUTHOR]

The present paper reports the effect of sintering temperature on the properties of Fe–SiC metal matrix nanocomposites (5 wt% SiC; 95 wt% Fe) prepared by powder metallurgy technique. Samples were synthesized by ball milling followed by compaction and then sintering in the temperature interval of 900 – 1100℃ for 3 h, respectively. X-ray diffraction, microstructure, density, hardness, wear and corrosion of prepared samples have been investigated. X-ray diffraction studies show the presence of iron (Fe) and silicon carbide (SiC) along with the presence of iron silicate (Fe3Si) phase. Iron silicate is formed as a result of reactive sintering between iron and silicon carbide particles. Scanning electron microscopy of the samples shows the dispersion of SiC in the whole Fe matrix. Density, hardness, wear and corrosion characteristics of the samples were investigated which varies for different sintering temperature interval. It is expected that the results of this paper will be helpful in developing metal matrix nanocomposites for various industrial applications. [ABSTRACT FROM AUTHOR]

Silver complex of sulfapyridine has been synthesized and characterized by IR, NMR and PL. The crystal structure has been determined by X-ray diffraction technique. Silver complex of sulfapyridine with secondary ligand pyridine crystallizes in monoclinic space group P21/n with lattice parameter: a = 17.8075(4)Å, b = 10.7885(3)Å, c = 17.8075(4)Å, β = 94.12(1)Å and Z = 4. To study the nature of intermolecular interactions and their quantitative contributions towards the crystal packing, Hirshfeld surfaces and accordingly the fingerprint plot analysis have been performed. Molecular properties such as NBO analysis, Homo-Lumo energy calculation have been carried out by DFT method. Furthermore, the antimicrobial activity of silver complex of sulfapyridine and free ligand is studied by the dilution method. [ABSTRACT FROM PUBLISHER]

CeO:M (Eu, Er and Dy) phosphors were synthesized by modified solid-state reaction technique at variable concentrations of Eu, Er and Dy. This technique is suitable for large-scale production and it is less time-consuming. The prepared samples were characterized by X-ray diffraction (XRD) technique, scanning electron microscopy (SEM), and Photoluminescence (PL) decay curve analysis. XRD patterns of the prepared samples confirm the cubic fluorite crystal structure of all phosphors. Crystallite size was calculated by using well known Scherer's formula. SEM images express good surface morphology with nanoflower like shape. Comparative studies of photoluminescence decay curves of CeO:M (Eu, Er and Dy) with different concentrations of dopant have been done. Decay constants for all prepared phosphors were calculated by curve fitting technique. Samples were excited under UV radiation for few nanoseconds at room temperature. The PL decay curves were measured for D→F transition of CeO:Eu,S→I transition of CeO:Er and F→H transition of CeO:Dy phosphors. Decay curve for CeO:Eu (1.5 mol%) phosphor shows optimum concentration with higher intensity of photoluminescence signals and comparatively higher decay constants. [ABSTRACT FROM AUTHOR]

Luminescence behaviour was displayed by dysprosium (Dy) doped BaTiO phosphor which was synthesized via solid state reaction method. The method is suitable for large scale production and useful for production of micron size phosphor. The sample was characterized by X-ray diffraction technique and crystallite size was calculated using Scherer's formula. Effects of optimized concentration of Dy on its thermoluminescence glow curve analysis were carried out for γ irradiation. For fixed concentration of dysprosium ions the TL glow curve was recorded using 6.7 °C s heating rate. Also for variable γ dose 1-2.5 kGy and optimized concentration of dysprosium ion i.e. 4 mol% were carried out. It is found that TL glow curve shows linear response with γ dose. Kinetic parameters were calculated using computerized glow curve deconvolution technique. Photoluminescence study of Dy doped BaTiO phosphor was carried out and it is found that the PL emission spectra in visible region had blue, green and red emission wavelength. CIE coordinate shows color rendering index and correlated color temperature for white light emission of Dy doped BaTiO phosphor. It may be used for visible light emission in display device applications and TL dosimetric applications. [ABSTRACT FROM AUTHOR]

Polycrystalline ceramics with chemical formula BaBiTiO, Pb BiTiO and SrBiTiO have been synthesized using co-precipitation route. In the present study optimization of calcination and sintering temperature is carried out and the relationship between sintering temperature and morphology, dielectric, and ferroelectric properties of the as-prepared samples is extensively investigated. Pellets of these samples were sintered at a range of temperatures 850, 950 and 1050 °C for 2 h. The phase formation of compounds calcined at different temperatures was studied using X-ray diffraction and scanning electron microscopy was used to examine the surface morphology. Crystallite and grain size was seen to increases with an increase in the calcination and sintering temperature respectively. The dielectric and ferroelectric properties of the ceramics were found to improve at a higher sintering temperature. [ABSTRACT FROM AUTHOR]

The utilization of substrate bias voltage to accelerate the sputtered ions in sputtering plasmas is an effective way to alter the properties of coating. In this work, hard nanocrystalline ZrWN coatings were sputter-deposited at relatively low deposition temperature (200 °C) by varying the substrate bias voltage from − 20 V to − 120 V. The effect of negative substrate bias on the microstructure and mechanical properties of nanocrystalline ZrWN coatings has been studied in detail employing X-ray diffraction, field emission scanning electron microscopy, energy dispersive x-ray spectroscopy, atomic force microscopy, transmission electron microscopy, nano-indentation and micro-indentation. The results indicate that the microstructure and morphology were significantly altered as a function of the increasing bias voltage. The bias voltage of − 20 V to − 60 V lead to enhanced ion current density and deposition rate while the resputtering effect was induced as the bias voltage increased beyond – 60 V. A dense glassy structure along with a maximum compressive stress (8 GPa) and hence optimum mechanical properties (hardness ~ 34 GPa, reduced elastic modulus E r ~ 145 GPa, wear resistance ~ 0.23 and fracture toughness ~ 2.25 MPa √ m ) were obtained in the ZrWN nanocrystalline coatings at a bias voltage of − 100 V. The results demonstrate that the enhancement of mechanical properties in ZrWN coatings can be achieved by carefully controlling the processing conditions, which in turn facilitate controlling the microstructure evolution, stress and mechanical properties. [ABSTRACT FROM AUTHOR]

The NaYF 4 phosphors codoped with Er 3+ -Yb 3+ have been synthesized by hydrothermal method using oleic acid as a chelating agent. The crystal structure and surface morphology has been identified with the help of powder X-ray diffraction (PXRD) and field emission scanning microscopy (FE-SEM) technique, respectively. The presence of different functional groups in the developed phosphors have been analyzed by using the Fourier transform infrared spectroscopy (FTIR) technique. The optical non-linear behavior of the prepared phosphors has been performed by using the excitation at 980 nm from a CW diode laser. The effect of Li + ions tri-doping on the structural and luminescence behavior of the Er 3+ -Yb 3+ codoped NaYF 4 phosphors has been discussed suitably. The effect of variation of pump power density on the UC emission intensity of different bands has been investigated. The optical temperature sensing behavior based on the green UC emissions of the Er 3+ -Yb 3+ -Li + tri-doped NaYF 4 phosphors under the excitation at very low pump power density (∼0.32 W/cm 2 ) has been studied. The results obtained from the present study indicate that the Er 3+ -Yb 3+ -Li + tri-doped NaYF 4 phosphors may be of particular interest in developing the NIR to visible upconverters, green display devices and temperature sensors. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis of pure and Cr-doped TiO 2 nanoparticles with different doping concentrations by using a cost-effective solvothermal method. The as-synthesized nanoparticles were characterized by using X-ray diffraction, transmission electron microscopy and UV–Vis spectroscopy to study their structural and optical properties. The XRD pattern showed the prepared material is pure anatase of the crystalline phase. Using TEM measurement, the average particles size is found to be about 11–13 nm while selective area electron diffraction (SAED) patterns have confirmed the polycrystalline nature of the nanoparticles. The size of the crystallite is observed to be decreased with an increase in dopant (Cr) concentration. UV–Vis absorption spectra showed enhanced absorption in the visible range in accordance with the doping concentration of Cr with a red shift in the absorption edge. The band gap energy of doped nanoparticles decreases in accordance with an increase in dopant concentration due to the reduced particles size. This presented work would be useful to tune the optical properties of doped and undoped metal oxide TiO 2 for its optoelectronic applications. [ABSTRACT FROM AUTHOR]

The scale-up synthesis of nZVI (zero-valent iron nanoparticles) was optimized by response surface modeling (RSM). The synthesized nZVI was employed for synergistic degradation of metronidazole (MNZ) or methyl orange (MO) in the presence of sodium borohydride (NaBH 4 ). Key parameters such as initial MNZ or MO concentration, nZVI concentration, and NaBH 4 concentration for MNZ or MO removal process was optimized using central composite design (CCD). Under the optimized conditions (nZVI concentration: 150 mg/L; NaBH 4 :0.1 M; interaction time: 25 min for MNZ and 30 min for MO; and MNZ or MO initial concentration: 40 mg/L), the removal was synergistically increased to 100% (MNZ) and 98.07 ± 1.1% (MO). When nZVI was applied without NaBH 4 , the removal of MNZ and MO were 50.62 ± 0.28 and 43.72 ± 0.29%, respectively. In the presence of NaBH 4 alone, the removal of MNZ or MO was 6.5 ± 1.1% and 4.2 ± 0.7%, respectively. Addition of NaBH 4 was found to enhance the remediation ability of nZVI. The MNZ or MO degradation followed pseudo–first–order kinetics. The degradation mechanism was studied by UV–visible spectroscopy, XRD, SEM-EDX, FT-IR, and BET analyses. The applicability of the process was tested with MNZ-spiked or MO-spiked lake water and ground water samples. [ABSTRACT FROM AUTHOR]

Behavior is displayed by samarium-doped LaAlO3 phosphor which was synthesized by solid state reaction method. For the synthesis of LaAlO3 with variable concentration of Sm (0.2–2.5 mol%) phosphor was calcinated at 1000 °C and sintered at 1250 °C following intermediate grinding. Synthesized sample was characterized by X-ray diffraction analysis and crystallite size was calculated by Scherer's formula. From photoluminescence (PL) spectra of prepared phosphors show broad excitation peak at 250 nm and emission at 566, 600, and 608 nm is obtained. The phosphor is prepared by high temperature synthesis method. Two peaks are obtained in the thermoluminescence (TL) glow curve for lower concentration of Samarium. Single prominent peak is obtained with further increase in the concentration of dopant. It is characteristic yellow-orange emission for samarium ion. The excitation spectra of LaAlO3:Sm3+ phosphor mainly consists of the charge transfer band (CTB) of Sm3+ located in 220–340 nm centered at 250 nm. The present phosphors can act as single host for yellow-orange-red light emission in display devices. The CIE coordinates were calculated by spectrophotometric method using the spectral energy distribution of the LaAlO3 :Sm3+ sample. TL glow curve was recorded for variable concentration of dopant with fixed UV exposer time (20 min) and fixed heating rate (5 °C·s−1). TL glow curve shows broad peak and kinetic parameters are calculated by computerized glow curve deconvolution technique. It is suggested that from TL glow curve analysis prepared phosphor may be useful for TL dosimetric application for UV exposure. [ABSTRACT FROM PUBLISHER]