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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]

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]

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]

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]

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]

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]

• 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 • 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]

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]

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]

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]

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]

Abstract: Single crystal gallium antimonide substrate was implanted with 200 keV iron ions with different ion fluences varying from 1×1014 to 1×1016 cm−2. Optical and structural properties have been investigated using the micro-Raman, Fourier transform infrared and grazing-angle X-ray diffraction measurements. Raman studies have shown the amorphization of gallium antimonide at higher fluences. Fourier transform infrared transmission studies over photon energy range 0.3 to 0.7 eV showed the change in the value of optical density over the entire photon energy range for the implanted samples as compared with the non-implanted sample. Damage profile probed by etching the sample was found to be non-uniformly distributed in the implanted sample. Grazing-angle X-ray diffraction spectra recorded at 1, 5 and 10° suggests the presence of defects and disorder in gallium antimonide after implantation. [Copyright &y& Elsevier]

Abstract: Indium phosphide samples were irradiated with swift (100 MeV) 56Fe7+ ions with different fluences varying from 5×1012 to 2×1014 ions cm−2 at room temperature. Atomic force microscopy (AFM) and X-ray diffraction (XRD) techniques have been used to investigate the irradiation effects. Atomic force microscopy observations revealed the presence of hillocks surrounded with valleys in all irradiated samples. The shape, size and height of the hillocks were found to vary with respect to ion fluences. Root mean square surface roughness was found to change from 0.33 nm to 7.49 nm. X-ray diffraction studies revealed increase in the amount of disorder in the irradiated samples as ion fluence increases. [Copyright &y& Elsevier]

Gadolinium-doped Y2O3 nanophosphor was synthesized by a solid-state reaction method, which could be used for large-scale production of phosphors. The structure of the phosphor sample was characterized by powder X-ray diffraction, field emission gun scanning electron microscopy and high-resolution transmission electron microscopy. The particle size was calculated from Scherer's formula. X-ray diffraction showed a grain size of 35-55 nm, in good agreement with the scanning electron microscopy image. The synthesized sample showed good morphology and connectivity, with grains and formation of a nano-sized prepared sample. The diffraction pattern was measured by transmission electron microscopy with a selected area diffraction pattern. The prepared phosphor was also examined by thermoluminescence; to record the glow curve, 1 mg phosphor was irradiated with ultraviolet at 254 nm at a fixed heating rate of 7 °C s−1. The sample showed a well-resolved peak at 99 °C for 1 mol% of Gd3+. A lower temperature peak showed less stability and more fading of the prepared sample. A thermoluminescence glow curve gives information about trapping parameters such as activation energy and trap depth, order of kinetics and frequency. All the kinetics were calculated by the peak shape method. [ABSTRACT FROM AUTHOR]

This paper presents the ferroelectric and dielectric properties of five-layer Aurivillius oxides (BaBiTiO, PbBiTiO and SrBiTiO) prepared by a solution combustion route with glycine as a fuel at low calcination temperature. The phase formation of these materials with pseudo-tetragonal structure was achieved after calcination at 750°C for 3 h; as confirmed by X-ray diffraction studies. Scanning electron microscopy of the sintered ceramics shows that the grains exhibit a plate-like morphology. The ferroelectric to paraelectric transition temperature ( T ) for Ba-, Pb- and Sr-based bismuth titanate ceramics was found to be 350, 280 and 260°C, respectively. All three materials show multiple relaxation phenomena and their electrical conductivity was found to be temperature dependent. The PbBiTiO ceramic possessed the highest value of activation energy (0.68 eV) and hence shows better ferroelectric properties, as compared to barium and strontium bismuth titanates. [ABSTRACT FROM AUTHOR]

Indium phosphide sample was irradiated with 200 MeV Ag9+ions for the fluence of 2 × 1013 ions cm−2. The sample was chemically etched down up to 240 nm depth to investigate the distribution of defects at different regions. Raman scattering and glancing incidence X-ray diffraction spectra were recorded at different depths. The stress estimated from Raman shift was found to increase with depth up to 160 nm and thereafter it decreased and at a depth of 224 nm sample did not show any stress. Phonon coherence length estimated from the Phonon Confinement Model was found to vary between 43 and 18 nm with respect to depth. Glancing incidence X-ray diffraction results revealed the decrease in crystallite size from 16.12 to 1.00 nm in different depth regions. [ABSTRACT FROM PUBLISHER]

The present paper reports the synthesis, photoluminescence (PL), and thermoluminescence (TL) studies of Eu-doped yttrium oxide (YO) phosphor using inorganic materials like YO, flux calcium fluoride, and europium oxide. The sample was prepared by the modified solid state reaction method, which is the most suitable for large-scale production. The prepared phosphor sample was characterized using powder X-ray diffraction, field emission gun scanning electron microscopy, high resolution transmission electron microscopy, Fourier transform infrared spectroscopy , PL, TL, and Commission Internationale de I'Eclairage techniques. The PL emission was observed in the range 417-632 nm ranges all visible regions for the YO phosphor doped with Eu. Excitation spectrum found at 254 nm. Sharp intense peaks found around 467, 534, 594, 612, and 632 nm with high intensity. From the XRD data, using the Scherer's formula, the calculated average crystallite size of Eu-doped YO phosphor is around 45 nm. TL study was carried out for the phosphor with UV irradiation. The present phosphor can act as single host for white light emission in display devices. [ABSTRACT FROM AUTHOR]

In this paper we review the luminescence properties of Pr-doped CaTiO phosphors, the different methods of sample preparation, and characterization of the materials by use of different techniques, for example X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermo-gravimetric analysis, and atomic force microscopy. Solid-state, sol-gel (SG), and combustion methods are most often used for preparation. The high calcining temperature of the solid-state method can be reduced by addition of rare earth oxides (lanthanide series) LnO and LuO. By use of tetra- n-butyl titanates and calcium nitrates as raw material in the modified solid-state method the luminous properties of samples can be optimized at lower sintering temperatures (600 °C) in less time. SG procedures lead to substantial reinforcement of red photoluminescence intensity so can be regarded as the best technique for phosphor preparation. [ABSTRACT FROM AUTHOR]

Thermal stability and mechanical properties of zirconium tungsten nitride (Zr–W–N) thin films have been studied. Nano-structured Zr–W–N thin films have been deposited on Si (100) substrates by reactive magnetron sputtering at varying substrate temperatures Ts (100°–600°C). For 100°C≤Ts ≤600°C, X-ray diffraction patterns of the films show a crystalline fcc phase with (111) and (200) preferred crystallographic orientations of grains. Maximum wear resistance (H/Er ~0.22) and maximum resistance to fatigue fracture (H3/Er 2 ~1.0GPa) have been obtained for the film deposited at Ts =400°C. Post annealing of the films deposited at 400°C has been carried out in air from 100°–600°C. Oxygen starts to be incorporated at 300°C and films begin to peel off above 400°C due to increase in oxygen incorporation. Hardness and elastic modulus of annealed films increase with increasing strain. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this work is to develop hydrophobic coatings for outdoor insulators using sputtering technique. Hafnium oxide is characterized by high dielectric constant, large band gap (5.6eV), high refractive index (2.1) and good mechanical, thermal and chemical properties. Hence HfO2 is suitable as a protective coating for outdoor insulators used in the transmission line and transformers. Hafnium oxide coatings were deposited on glass substrates by DC magnetron sputtering technique at a sputtering pressure of 5mTorr, 10mTorr, 15mTorr, 20mTorr and 25mTorr. The deposited films were characterized by techniques like X-ray diffraction (XRD), atomic force microscopy (AFM), water contact angle goniometry and UV–vis-NIR spectrophotometer. The average crystallite size calculated from XRD peaks shows that it increases with increase in sputtering pressure up to 15mTorr and then it starts decreasing. The roughness calculated from AFM images shows the similar trend. The deposited films were found to be hydrophobic and transparent. The hydrophobicity of the films was correlated with the roughness calculated from AFM. The effect of sputtering pressure was also investigated on optical band gap and refractive index calculated from transmission and absorption data. The electrical resistivity was found to be high, thus ensuring insulating property of the deposited films. [Copyright &y& Elsevier]

The misfolding and aggregation of the intrinsically disordered, microtubule-associated tau protein into neurofibrillary tangles is implicated in the pathogenesis of Alzheimer's disease. However, the mechanisms of tau aggregation and toxicity remain unknown. Recent work has shown that anionic lipid membranes can induce tau aggregation and that membrane permeabilization may serve as a pathway by which protein aggregates exert toxicity, suggesting that the plasma membrane may play dual roles in tau pathology. This prompted our investigation to assess tau's propensity to interact with membranes and to elucidate the mutually disruptive structural perturbations the interactions induce in both tau and the membrane. We show that although highly charged and soluble, the full-length tau (hTau40) is also highly surface active, selectively inserts into anionic DMPG lipid monolayers and induces membrane morphological changes. To resolve molecular-scale structural details of hTau40 associated with lipid membranes, X-ray and neutron scattering techniques are utilized. X-ray reflectivity indicates hTau40s presence underneath a DMPG monolayer and penetration into the lipid headgroups and tailgroups, whereas grazing incidence X-ray diffraction shows that hTau40 insertion disrupts lipid packing. Moreover, both air/water and DMPG lipid membrane interfaces induce the disordered hTau40 to partially adopt a more compact conformation with density similar to that of a folded protein. Neutron reflectivity shows that tau completely disrupts supported DMPG bilayers while leaving the neutral DPPC bilayer intact. Our results show that hTau40s strong interaction with anionic lipids induces tau structural compaction and membrane disruption, suggesting possible membrane-based mechanisms of tau aggregation and toxicity in neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

LDPE/EVA/PCR blends having fixed percentage of PCR were prepared by melt mixing and irradiated to different radiation doses using electron beam. Gel fraction and crosslinking density of the blends were found to increase with increase in EVA content in the formulation, suggesting higher radiation sensitivity of EVA. The heat of mixing and polymer-polymer interaction parameter indicated better miscibility between EVA/PCR than between LDPE/PCR and LDPE/EVA. Dynamic mechanical properties of the blends were found to significantly vary with the variation in the EVA fraction in the blends. In the composition range studied the storage modulus decreased from 3.8 × 10 to ∼1 × 10 Pa at strain amplitude of 5 × 10 m. The experimentally obtained data deviated significantly from both the series as well as parallel model. The bulk density showed a positive deviation from additive rule. The X-ray diffraction pattern of the blends revealed reduction in the crystallinity of LDPE on blend formation. DSC thermograms of blends did not indicate any significant shift in the melting peaks, indicating immiscibility of LDPE and EVA domains in the presence of PCR. [ABSTRACT FROM AUTHOR]

Summary: A high concentration of Arsenic (As) contamination in ground water has been reported in the village of Kaudikasa in Rajnandgaon district, wherein around 10% of the population is suffering from As-borne diseases. The region does not share any demographic or geological similarity with the sedimentary aquifers of the Bengal Delta Plain in Eastern India, but represents an igneous terrain with elevated As concentrations in groundwater. There is limited information about the source of As in groundwater and its mobility constraints. In this area, almost all the wells are located in the granitic terrain with pegmatitic intrusions. Most of these wells are characterized by As concentration above the World Health Organization () and the BIS (Bureau of Indian Standards) standards, with the highest being found in a well with more than 250μg/L of As. Here we report petrographic studies of the granitic host rock and X-ray diffraction results that indicate that altered realgar (α-As4S4), para realgar (AsS), and/or tennantite (Cu12As4S13), are the main mineral that contain As. This element is leached during the weathering and water–rock interactions. Microprobe analysis of the altered realgar grains of in pegmatitic intrusions of the host granite indicate 23–27wt.% As. Remote sensing is useful to delineate the source of this contaminant, which appears to lie at the intersection of a mineralized NW-SE and N–S lineaments associated with the Kotri rift zone. These lineaments are structurally controlled as rifting followed by thrusting and other types of faulting caused left-lateral displacement of N–S Kotri lineament along a NW-SE fault plane showing sinistral shearing. This process caused water drainage in the areas to flow along these highly mineralized weak zones. Thus, the water becomes highly contaminated due to leaching of minerals at the intersection of these lineaments, clearly visible at two areas of high contamination that lie very near to this intersection over granitic rock. The source of As affecting the Rajnandgaon district is located in granites that have pegmatitic intrusions likely generated by hydrothermal activity. [Copyright &y& Elsevier]

Abstract: Metal nanostructures have unusual physicochemical properties and biological activities compared to their bulk parent materials. Thus in recent years a number of physical, chemical and biological techniques were applied for the development of metal nanoparticles (NP). Here we have synthesized silver and gold nanoparticles (AgNPs and AuNPs) by using leaves extracts of Rosa rugosa. Surface plasmon resonance spectra for silver and gold are obtained at 451 and 578nm with brown yellow and pink-red color, respectively. AgNPs and AuNPs vary in size according to different leaves extract and metal concentration used for the synthesis. Different instrumental techniques were applied to characterize the synthesized AgNPs and AuNPs viz. UV–vis, TEM, XRD, FTIR, Zetasizer and EDX. The synthesized NPs were mostly spherical (in case of AgNPs) with some triangular and hexagonal (especially in case of AuNPs) in shapes with an average size of 12 and 11nm for AgNPs and AuNPs, respectively. [Copyright &y& Elsevier]

Abstract: In this paper we have reported the green synthesis of silver (AgNPs) and gold (AuNPs) nanoparticles by reduction of silver nitrate and chloroauric acid solutions, respectively, using fruit extract of Tanacetum vulgare; commonly found plant in Finland. The process for the synthesis of AgNPs and AuNPs is rapid, novel and ecofriendly. Formation of the AgNPs and AuNPs were confirmed by surface plasmon spectra using UV–Vis spectrophotometer and absorbance peaks at 452 and 546nm. Different tansy fruit extract concentration (TFE), silver and gold ion concentration, temperature and contact times were experimented in the synthesis of AgNPs and AuNPs. The properties of prepared nanoparticles were characterized by TEM, XRD, EDX and FTIR. Finally zeta potential values at various pH were analyzed along with corresponding SPR spectra. [Copyright &y& Elsevier]

Thin film of high purity (99.999 %) Cd1-xZnxTe (where x =0.02, 0.04, 0.06, 0.08) was prepared by high vacuum technique (HVTx10-6 Torr), on glass substrates at different substrate temperatures. The film deposited at lower temperature was annealed for one hour in vacuum of 5x10-3 torr at as-deposited to 300K. Structural investigation has been carried out using the X-ray diffraction technique. Scanning electron microscopy have been used to study the morphological behaviour of the thin films. At the lower deposition temperature the film represents amorphous nature but with increasing value of x the film exhibits polycrystalline nature. The SEM indicate that in amorphous state the surfaces are non uniform but at higher annealing temperature the film surfaces are uniform. Effect of annealing on carrier concentration and Hall mobility has been studied. From the Hall effect study various electrical parameters have been estimated. [ABSTRACT FROM AUTHOR]

ZnTe nanoparticles have been synthesized by chemical synthesis method, which is based on the chemical replacement reaction between the chemical compounds. Structural analysis of ZnTe nanoparticles has been performed by using x-ray diffraction techniques. It has been found that the average particle size is 2.6 nm using uv-vis spectroscopy. DC and AC electrical conductivities of ZnTe nanoparticles have been studied. Conduction mechanism is described in brief. The activation energies have also been determined. The results indicate that ZnTe behaves as a semiconducting material. [ABSTRACT FROM AUTHOR]

Abstract: The effects of 70MeV irradiation of iron ions in p-type silicon at fluences between 1×1012 and 5×1014 ionscm−2 were investigated by high resolution X-ray diffraction (HRXRD), electron spin resonance (ESR) and current–voltage measurements. The irradiated samples were isochronally annealed in nitrogen ambient up to 973K for 2min using the rapid thermal annealing (RTA) system. The screw dislocation density of the annealed sample (5×1014 ionscm−2) estimated at each stage of annealing from the broadening of the HRXRD peak was observed to change from 8.70×107 to 1.58×107 cm−2 with increasing temperatures. The strain and stress parameters estimated at each stage of annealing using the FWHM of ω-scan clearly indicate relative trend towards the un-irradiated silicon sample. The electron spin resonance studies indicate the presence of the dangling bond state of silicon (Siomplex defects. The annealing at 873K was found to be sufficient for complete removal of the defect centers induced due to irradiation. The I–V studies performed on the irradiated samples before and after annealing indicate that the defects created as a consequence of irradiation trap the charge carriers. [Copyright &y& Elsevier]

Liquid phase catalytic hydroxylation of phenol was carried out over ternary hydrotalcites containing copper, nickel and aluminum using hydrogen peroxide as oxidant. The influence of various reaction parameters, namely, substrate:catalyst ratio, substrate:oxidant ratio, nature of oxidant, solvent, pH, time-on-stream, reaction temperature and calcination temperature on the activity and selectivity for the “sought for” reaction, were studied. The catalysts were synthesized by the coprecipitation technique using metal nitrates and a NaOH/Na2CO3 mixture. Hydroxylation of phenol over these catalysts resulted mainly in the formation of catechol and hydroquinone. Among the catalysts studied, CuNiAl3-5 ((Cu+Ni)/Al=3.0; Cu/Ni=5.0) and CuNiAl2-1 ((Cu+Ni)/Al=2.0; Cu/Ni=1.0) showed maximum activity with a catechol:hydroquinone ratio close to 1.6. An increase in the substrate:catalyst ratio enhanced the conversion of phenol over these catalysts. With respect to the influence of reaction temperature, the conversion increased up to 65 °C and decreased when the temperature was further increased. Oxidants other than H2O2 and solvents other than water have not showed measurable conversion of phenol. Time-on-stream studies indicated that around 90% of conversion of phenol was achieved in 10 min and longer reaction time did not significantly enhance the conversion. Among the calcined samples studied, that calcined at 800 °C showed a maximum activity for phenol hydroxylation; however, the activities of calcined catalysts were lower than those of fresh hydrotalcites. The observed variation in the activity may be attributed to the copper concentration, especially those present on the surface. A reaction pathway involving hydroxy radical is proposed for the formation of dihydroxybenzenes. [Copyright &y& Elsevier]

• Five new cocrystals of TMZ with aromatic acids, aromatic amide, and TMZ monohydrate were synthesized. • The cocrystal formations are stabilized by N–H···O, O–H···O, O–H···N hydrogen bonds and π⋅⋅⋅π interactions. • The cocrystals demonstrated better stability and dissolution properties compared to pure TMZ. • TMZ-4NO 2 BA⋅H 2 O cocrystal hydrate showed improved cytotoxicity than the pure drug on LN229 Glioblastoma cells. Temozolomide (TMZ), the first-line anti-glioblastoma prodrug, hydrolyses at physiological pH (pH>7) in the aqueous medium. With a short elimination half-life (T1/2) of ∼1.8 h, TMZ hydrolytically metabolizes to its metabolites 5-(3-monomethyl-1-triazeno)imidazole-4-carboxamide (MTIC) and then further into 5-aminoimidazole-4-carboxamide (AIC). The objective of current work is to develop novel stable cocrystals of TMZ with safe coformers such as isonicotinic acid (INA), 4-nitrobenzoic acid (4NO 2 BA), 3-aminobenzoic acid (3ABA), salicylic acid (2-hydroxybenzoic acid, 2HBA) and aromatic amide 4-hydroxybenzamide (4HBz) to stabilize the drug in a cocrystal form. All the cocrystals were characterized by single crystal X-ray diffraction (SCXRD), powder XRD (PXRD), and thermogravimetry-differential scanning calorimetry (TG-DSC) analyses. Dissolution profiling in phosphate buffer saline pH 6.8 revealed that the drug release rate from TMZ–2HBA Form II cocrystals and TMZ–4NO 2 BA⋅H 2 O cocrystal hydrate were significantly higher than pure TMZ. The hydrolytic stability of all the cocrystals and hydrates in pH 6.8 buffer was longer than that of TMZ while showing three-fold hydrolytic stability in case of TMZ–4NO 2 BA⋅H 2 O and TMZ-2HBA cocrystals. Their lattice arrangements in SCXRD explain the improved hydrolytic stability in these two cases. In vitro studies on human glioblastoma cell lines showed a significant improvement in the cytotoxicity and possibly improved bioavailability of TMZ–4NO 2 BA⋅H 2 O cocrystal hydrate. [Display omitted] [ABSTRACT FROM AUTHOR]

Nanocrystalline α-iron nitride films have been prepared using reactive ion-beam sputtering. Films develop significant perpendicualr magnetic anisotropy (PMA) with increasing thickness. A comparison of x-ray diffraction patterns taken with scattering vectors in the film plane and out of the film plane provides a clear evidence for development of compressive strain in the film plane with thickness. Thermal annealing results in relaxation of the strain, which correlates very well with the relaxation of PMA. This suggests that the observed PMA is a consequence of the breaking of the symmetry of the crystal structure due to the compressive strain. [ABSTRACT FROM AUTHOR]

This paper reports the preparation of Eu 3+ doped Gadolinium oxyorthosilicate (Gd 2 SiO 5 :Eu 3+ ) phosphor with different concentration of Eu 3+ (0.1–2.5 mol%) using the modified solid state reaction method. The synthesis procedure of the Gd 2 SiO 5 :Eu 3+ phosphor using inorganic materials such as Gd 2 O 3 , silicon dioxide (SiO 2 ), europium oxide (Eu 2 O 3 ) and boric acid (H 3 BO 3 ) as flux is discussed in detail. The prepared phosphor samples were characterized by using X-Ray Diffraction (XRD), Field Emission Gun Scanning Electron Microscopy (FEGSEM), Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR), Photoluminescence (PL) and Thermoluminescence (TL). The Commission Internationale de l′Eclairage(CIE) coordinates were also calculated. The PL emission was observed in the 350–630 nm range for the Gd 2 SiO 5 :Eu 3+ phosphor. PL excitation peaks were observed at 266, 275, 312 and 395 nm while the emission peaks were observed at 380, 416, 437, 545, 579, 589, 607, 615 and 628 nm. The emission peak at 615 nm was the most intense peak for all the different Eu 3+ concentration samples. From the XRD data, using the Scherrer's formula, the average crystallite size of the Gd 2 SiO 5 :Eu 3+ phosphor was calculated to be 33 nm. TL was carried out for the phosphor after both UV and gamma irradiation. The TL response of the Gd 2 SiO 5 :Eu 3+ phosphor for the two different radiations was compared and studied in detail. It was found that the present phosphor can acts as a single host for red emission (1.5 mol%) for display devices and light emitting diode (LED) and white light emission for Eu 3+ (0.1 mol%) and it might be used as a TL dosimetric material for gamma dose detection. [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]