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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]

NiO:ZnO nanocomposite is examined using a cost-effective gel method. X-ray pattern synthesis demonstrates that the prepared NiO:ZnO nanocomposites have a high crystallization with an average size of a 50 nm crystalline bead. SEM images reveal the morphology and particle size distribution of the NiO:ZnO Nano compound, and the average nanoparticle size was about 70 nm. The results showed that antibacterial studies against positive germs (G + Ve) for S. aureus and negative Gram (G-Ve) bacteria from E-Coli for concentration (50, 75 and 100 g / ml). The results showed that the antibacterial activity of NiO:ZnO nanocomposite against S. aureus bacteria was higher than that of E. coli. [ABSTRACT FROM AUTHOR]

Abstract Different formulations of geopolymers were synthesized in acidic media (phosphoric acid) starting from three different raw metakaolin materials to identify compositions of interest. Four different property groups were highlighted based on the most favorable thermal and water resistance properties (while maintaining acceptable mechanical properties). The groups were related to the chemical composition, setting time and setting temperature of the synthesized geopolymers. Indeed, mechanical strength was determined by chemical composition, such as the aluminum content and the amount of water in each sample. The results showed that the sample with Si/Al ≥ 1 and Al/ P = 1 exhibited compressive stress to rupture values ranging between 66 and 120 MPa and was thermal resistant. Water resistance with a mechanical strength of 50 MPa was obtained for the samples with Al/ P = 1 or 4 and Si/Al ≤ 1. This work highlights the possibility of selecting a specific property associated with the mechanical performance for an acidic geopolymer. Highlights • Acid geopolymer with various properties were determined. • The Al/P and Si/Al ratios control the mechanical properties. • Thermal and water resistant materials depend on the quantity of aluminum. • Water content in materials control the mechanical properties. [ABSTRACT FROM AUTHOR]

Micro analysis of pigments, plaster layers and binding media using SEMEDX, XRD and FTIR within Elshinawy palace proved that blue pigment is cobalt blue, green pigment is malachite yellow pigment is goethite, and binding medium is animal glue. These paintings were carried out on a ground layer of gypsum with animal glue as binding medium, in addition to a portion of calcite added deliberately to increase brightness of gypsum. The protein materials of animal glue gave in alkaline medium and in presence of copper a blue violet or purple color called Birut Molecules. [ABSTRACT FROM AUTHOR]

We proposed a novel ex-situ sol-gel synthesis of Nd3+ (0.7 mol%) and Yb3+ (X; X = 0.0, 0.7, 1.5, 3.0 mol%) ion co-doped Zinc-Silicate (SZNYX) dense glass-ceramic(DGC) samples. The structural analyses of the SZNY07-DGC sample were performed at different annealing temperatures using X-ray diffraction (XRD) analysis and Fourier transforms infrared (FTIR) spectroscopy. The tetragonal willemite Zn 2 SiO 4 structure with an R-3(148) space group was confirmed from XRD results. The formation of the pure oxide phases (bridging oxygen) was noticed at FTIR spectra with the complete removal of hydroxyl impurity at higher annealing temperatures. The presence of ZnO crystallites with the inter-planer spacing of ⁓ 0.28 nm and Nd3+/Yb3+ ion pair in an amorphous silica host was confirmed via transmission electron microscopy (TEM) and TEM-energy dispersive spectroscopy (EDS) respectively. The white up-conversion luminescence (UCL) under a 980 nm excitation was attributed to the simultaneous emission of wavelength in the visible spectrum. The intensity of UCL was initially rising with an increase in Yb3+ ion concentration whereas the optimized luminescence was obtained for samples with 1.5 mol% Yb3+ ion concentration. The CIE chromaticity coordinates (0.34, 0.35) of corresponding UCL spectra were invariant with the change in Yb3+ ion concentration. The photoluminescence (PL) confocal mapping of the SZNY15-DGC sample was performed at different locations under a 980 nm laser excitation source which turned out non-uniform in nature throughout the surface. Thus as-synthesized SZNYX-DGC samples have spectacular upconversion luminescence for near-infrared excitation which may be utilized in thermal sensing, photovoltaic, displays, and photonic devices. [ABSTRACT FROM AUTHOR]

In this study, cupric oxide (CuO) nanoparticles were prepared using sonochemical method. The prepared nanoparticles were studied using X‐ray diffraction (XRD) pattern, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) methods. The colloidal chitosan (CS) solution was prepared using ultrasound irradiation method and simultaneously mixed with CuO nanoparticles. The coatings of colloidal solution with and without CuO nanoparticles were studied through TEM images. The cotton fabrics were separately soaked in the prepared nanoparticle‐containing (hybrid) solutions by sonication method followed by pad‐dry‐cure method. The structural, functional, and morphological analyses of the coated and uncoated fabrics were performed using XRD, FTIR‐attenuated total reflectance, and SEM analyses, respectively. The hybrid‐coated cotton fabrics showed better antibacterial activity against Staphylococcus aureus and Escherichia coli. The bioactivity performance of the coated fabrics was in the order of CuO‐coated fabric > CS‐coated fabric. [ABSTRACT FROM AUTHOR]

A method of studying the phase composition of compact ceramics based on titanium nitride is described and the results of the X-ray diffraction analysis of the material obtained are presented. It is shown that, in the process of nitridation, the phase composition of the surface of the specimen changes and every step of the process is characterized by an individual and definite set of phase states. [ABSTRACT FROM AUTHOR]

• Simulation via molecular dynamics of mechanical properties in (U,Pu)O2 as a function of irradiation dose. • Calculation of simulated XRD patterns as a function of irradiation dose. • Correlation between XRD patterns and microstructural evolution as a function of irradiation dose including swelling. [Display omitted] Molecular dynamics simulations of microstructural evolution under irradiation of (U,Pu)O 2 solid solutions have been carried out with the Frenkel pair accumulation method with two empirical potentials. Simulated X-Ray diffraction patterns have been systematically generated along the irradiation pathway from the computed atomistic configurations. Description of the X-Ray diffraction patterns for each of these well characterized damage microstructure snapshots is discussed. Attempt to correlate the features of the X-Ray diffraction peaks with the microstructural evolution with irradiation dose is also provided. Special attention is dedicated to the swelling effect. [ABSTRACT FROM AUTHOR]

The present paper reports the thermoluminescence (TL) glow curve of Eu-activated SrAlO phosphor with different UV exposure times. Evaluation of kinetic parameters was done by the peak shape method. The recorded glow curve shifts towards lower temperatures with respect to increasing UV exposure time. The peaks were found at 146.76, 141.34 and 140.37 °C, respectively, for 5, 10 and 15 min of UV exposure using the heating rate of 3°C s. The glow peak shows the second-order kinetics. Different kinetic parameters, i.e. trap depth, order of kinetics, activation energy, and frequency factor are also calculated. The XRD pattern of the sample is compared with reported XRD using the software match. [ABSTRACT FROM AUTHOR]

In this study, facile and ecofriendly methods have been developed for the biosynthesis of silver nanoparticles from silver nitrate using the seed extract of Strychnos potatorum, a natural phytocoagulant. The effect of room temperature stirring, water bath heating and autoclaving on nanoparticle synthesis was studied. The water soluble compounds in the extract serve as reducing and stabilising agents. Analytical techniques such as UV–visible spectroscopy, transmission electron microscopy (TEM) and X‐ray diffraction were used to characterise the synthesised nanoparticles. By tuning the reaction conditions, size controlled spherical nanoparticles of around 14.1 ± 4.8 nm were generated. The face centred cubic crystalline structure of the nanoparticles is confirmed from the observed peaks corresponding to (111), (200), (220) and (311) planes in the XRD pattern, concentric rings with intermittent bright dots in selected‐area electron diffraction patterns and clear lattice fringes in high‐resolution TEM images. With Fourier transform infrared spectroscopy and Raman spectroscopy, a probable mechanism involved in the reduction and stabilisation of nanoparticles has been investigated. As the silver nanoparticles are encapsulated with functional groups, they can be easily integrated for various biomedical applications. [ABSTRACT FROM AUTHOR]

Two aluminate spinel materials (ZnAlO and NiAlO) were synthesized by the citrate precursor method. The citrate precursors consisting of coprecipitated citrates of Zn or Ni and aluminum were first subjected to thermal analysis (TG-DSC) for determining the optimum temperature for annealing. Two step decomposition was observed incorporating dehydration and formation of the aluminate. The second step gives an endo peak (−2937 J/g) at 356 °C in the DSC curve of the coprecipitated nickel(II) citrate-aluminum citrate gel in O atmosphere. Kinetic/mechanistic analysis of the TG data has also been carried out and values of E, Δ S, Δ G, and A were approximated. On the basis of the findings, 450 °C has been chosen for annealing of the gels. Annealing has also been done at 650 °C for 1 h in muffle furnace in an attempt to obtain nanometric particles of aluminates (MAlO) {M = Ni, Zn} and to find out their magnetic properties which could render them useful for chemical sensing applications, etc. The TG-DSC curves of various powders which were obtained on annealing at the two temperatures did exhibit thermal instability when carried out in N atmosphere. NiAlO and ZnAlO spinels (particle size 17 and 34 nm, respectively) are obtained in pure crystalline phase at 650 °C. ZnAlO prepared this way shows coercivity values of 470 and 58.37 G and NiAlO, 107 and 23.24 G when annealed at 450 and 650 °C, respectively. ZnAlO prepared by a polymer precursor method and annealed at 1000 °C, has earlier been reported to have coercivity value of 469 G. Thus, the citrate precursor method is good for the synthesis of ZnAlO, producing single phase nanocrystalline powder of high quality and crystallinity. The value of magnetization was found to be small in the present case for the NiAlO spinel obtained at 450 °C. [ABSTRACT FROM AUTHOR]

Abstract: ZnAl layered double hydroxides (LDHs) with nitrate as the charge balancing anion in the interlayer space were synthesized by precipitation from homogeneous solution using urea hydrolysis. The composition of the synthesis mixture and the synthesis time were varied in order to identify the parameters, which control if nitrate or carbonate will be the interlayer anion. Especially, the addition of ammonium nitrate turned out to be an effective tool for the synthesis of nitrate containing ZnAl LDHs independent from the synthesis time. Results are mainly based on powder X-ray diffraction measurements of the obtained samples. [Copyright &y& Elsevier]

Starch from Moth bean (Phaseolus acontifolius Jacq) was isolated and some of the important characteristic determined. The yield of starch was 38.8% w/w of a whole raw seed basis. The shape of the starch granule was oval to round shaped, with granules 9-59 μm in diameter. Scanning electron micrograph revealed the presence of smooth surfaces. TGA thermogram value revealed that moth bean starch possesses The gelatinization temperature range was 72-78-82°C .The X-ray diffraction pattern was of the 'C' type and the intensity of X-ray was much stronger than in tuber starches. The Relative viscoamylograph examination of the starch paste showed high paste viscosity as compared to Potato starch. [ABSTRACT FROM AUTHOR]

ZnO thin films are used for a number of MEMS-based sensors because of the piezoelectric and semiconducting properties. In certain class of devices, especially those using surface acoustic wave (SAW) technology on a layered substrate (such as ZnO on Si), it is a requirement to grow several micron thick ZnO layer which must be highly c axis oriented. In this attempt, we have deposited ZnO films by sol-gel spin process and using three different concentrations of 10%, 12.5%, and 25% of sol using zinc acetate as the precursor material and characterized for their thickness and other associated characteristics. The XRD pattern showed diffraction peaks of the hexagonal ZnO phase. The intensity of the 002 peak was much low for low-strength sols indicating substantial preferred orientation of the crystallites perpendicular to the sample surface. The crystallite size was estimated to be about 45 nm from the 100 diffraction peak. For the sample with 25% strength of the sol, the XRD pattern showed diffraction peaks of the hexagonal ZnO phase. The crystallite size was estimated as about 60 nm from the 100 peak and about 145 nm from the 002 peak. The TEM results showed fine nanoparticles with hexagonal ZnO crystal structure and morphology dependence upon the sol strength. Faceted morphology of hexagonal ZnO nanostructures has been obtained. The results would find application in nanoelectronic piezoelectric sensors. [ABSTRACT FROM PUBLISHER]

Abstract: Cobalt containing hexagonal mesoporous molecular sieves (MCM-41) were prepared by different methods viz., direct hydrothermal synthesis, grafting and immobilization. The calcined material was characterized by various spectroscopic tools such as powder X-ray diffraction (XRD), N2 adsorption–desorption isotherms, Fourier transformed infra-red (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance UV–vis and X-ray photoelectron spectroscopy (XPS). The XRD patterns show the highly intense (100) reflection peak in the range 2–3° (2θ angle), characteristic of mesoporous material. Higher order reflection peaks suggest highly ordered mesoporous structure. N2 adsorption–desorption isotherms are of type IV according to IUPAC classification and the steep rise in the isotherms in the narrow range 3.5–4.5 of relative pressure (P/P 0) is due to the condensation of N2 gas molecules in the pores (characteristic of mesoporous structure). In FT-IR increase in the intensity of band at 960cm−1 with the increase of the cobalt content in Co-MCM-41 samples indicate the incorporation of cobalt ions in the framework of MCM-41. SEM and TEM reveal spherical morphology for the cobalt substituted MCM-41. UV–vis spectra demonstrate the characteristic features of framework and extraframework cobalt in MCM-41. Cobalt is in +2 oxidation state as evidenced from UV–vis and XPS. The catalysts were tested for the side chain oxidation of ethylbenzene using 70wt.% tert-butyl hydrogen peroxide as an oxidant with and without the use of solvent. Solvents have effect in the catalytic activity and selectivity. In the absence of solvent, substituted cobalt [Co-MCM-41 (50)] in the framework of MCM-41 gives maximum ethylbenzene conversion while higher selectivity to acetophenone was achieved over immobilized cobalt on the MCM-41. Leaching data shows, immobilized cobalt catalyst is well hetrogenized. [Copyright &y& Elsevier]

Powder X-ray diffraction (XRD) is employed to identify the phase structure of Al-substituted nickel hydroxide, and its structural change after ageing treatment or charge/discharge cycles. The cell constants and the crystalline size of nickel hydroxides have been obtained by analysing the XRD pattern with Si as an internal standard. Results show that Al-substituted α-phase nickel hydroxide is very stable in strong alkaline medium even after 100 charge/discharge cycles. [Copyright &y& Elsevier]