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Abstract\nHighlightsThe calcium ferrite nanoparticles were made by the sol–gel process. X-ray diffraction, a scanning electron microscope, and UV–vis spectroscopy were used to analyze the material. There is an orthorhombic phase in the space group Pnma. There were four techniques used to calculate the average crystallite size. Using ImageJ software, the particles were aggregated and their size was ascertained. Using energy-dispersive X-ray (EDX) analysis, the composition of the material was ascertained. 2.29 eV was determined to be the band gap. Vibrating test magnetometer (VSM) provided an explanation for the materials’ magnetic property. A decreased band gap energy is responsible for the 90% degradation of malachite green dye at a concentration of 15 mg/L in 150 min, with a four-cycle reusability.Calcium ferrite nanoparticles were successfully synthesized by sol–gel assisted combustion method using leaf extract of Brassica oleracea as fuel.To the best of the author’s knowledge, no such case study that reports the synthesis of calcium ferrite nanoparticles by using leaf extract of Brassica oleracea is previously reported in academic literature.The method is cost-effective and convenient without the use of any chemical fuel agents.The synthesized prepared material efficiently removes malachite green dye, commonly used in industries for dyeing silk and nylon, from the solution.More than 90 % removal efficiency for MB.The material displayed excellent stability and reusability for dyes adsorption.Results were validated with pseudo-first-order kinetic model.Calcium ferrite nanoparticles were successfully synthesized by sol–gel assisted combustion method using leaf extract of Brassica oleracea as fuel.To the best of the author’s knowledge, no such case study that reports the synthesis of calcium ferrite nanoparticles by using leaf extract of Brassica oleracea is previously reported in academic literature.The method is cost-effective and convenient without the use of any chemical fuel agents.The synthesized prepared material efficiently removes malachite green dye, commonly used in industries for dyeing silk and nylon, from the solution.More than 90 % removal efficiency for MB.The material displayed excellent stability and reusability for dyes adsorption.Results were validated with pseudo-first-order kinetic model. [ABSTRACT FROM AUTHOR]

The current study demonstrates the effect of Ni-substitution on the structural, dielectric and ferroelectric properties of Ba0.90Sr0.10Ti1-xNixO3 (where x = 0.000, 0.005, 0.015 and 0.025) ceramics, synthesized by solid-state reaction approach. A pure perovskite phase with tetragonal structure has been confirmed by X-ray diffraction (XRD) analysis. Scanning electron microscope (SEM) images revealed change in microstructure. The dielectric behavior of the prepared ceramics was investigated as a function of temperature (30–150°C) at different frequencies. The results indicate that there is an increase in dielectric constant (ϵRT) and low dielectric loss (tanδRT) were obtained at room temperature by substitution of Ni2+ ions in BST ceramics, offering a promising material for capacitor applications at room temperature. Room temperature P-E loops were recorded at different applied electric fields and typical hysteresis loops were obtained. Improvement in the values of Pr and Pmax was observed by substitution of Ni2+ ions. [ABSTRACT FROM AUTHOR]

A novel Bi-Mg-O composite nano-catalyst was prepared by using Bi(NO3)3 and nano-MgO. Prepared catalyst was characterized using x-ray diffraction (XRD) analysis, scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) technique which confirms its nano-crystalline nature and composition. The synthesized novel catalyst Bi-Mg-O was found to be competent catalyst for the synthesis of spirooxindole derivatives by multicomponent reaction of isatin, dimedone, malononitrile and 4H-pyran derivatives by reaction of dimedone, aryl aldehydes and malononitrile using ethanol as solvent at room temperature. The nanocatalyst proved to be recyclable as it is recycled and recovered for three runs without notable loss in catalytic activity. All synthesized derivatives were obtained in exemplary yields. Novel recyclable nanocatalyst, good yields of products, and benign reaction conditions are the noteworthy aspects of the present protocol. [ABSTRACT FROM AUTHOR]

Zingiber officinale (known as ginger), a natural flowering plant of Zingiberaceae family, was taken to investigate its possible utilization in a textile material. Zingiber officinale fibers (ZOFs) were obtained from the plant root. The cellulose, hemicellulose, and lignin contents of ZOFs were determined. Elemental analysis of ZOFs was carried out with energy dispersive X-ray analysis (EDX) instrument. Surface morphology of fibers was investigated with a scanning electron microscope (SEM) instrument. The chemical functional groups of ZOFs were confirmed with Fourier transform-infrared spectroscopy (FT-IR). The crystalline structure of ZOFs was analyzed with X-ray diffraction (XRD), and then the crystallinity index was calculated as 78.81%. In addition to this, mechanical properties of ZOFs were investigated with Shimadzu Ag-X machine. The EDX and FT-IR results show that ZOFs have cellulosic structure. Furthermore, it was obtained that ZOFs have rough surface structure and the thickness is approximately 155 µm. The physical properties of ZOFs are substantial enough for its usage as a textile fiber. [ABSTRACT FROM AUTHOR]

In the present scenario, the searching for novel plant fibers able to be used as reinforcement of polymer composites is highly appreciable. This study deals with extraction and characterization of Eleusine indica grass fibers extracted from its stem by manual retting process. From this study, it was found that the Eleusine indica has higher cellulose of 61.3 wt% content, density of 1143 kg/m3, average tensile strength and Young's modulus equal to 22 MPa and 10.75 GPa, respectively. From the XRD studies, it was noted that the Crystallinity Index (CI) of Eleusine indica was 45%. The surface morphology of Eleusine indica grass was examined using a Scanning Electron Microscope (SEM) and Chemical functional group were confirmed by Fourier transform infrared spectroscopy (FT-IR). The thermal stability of EIF was evaluated using TG and DTG curves from Thermogravimetric (TG) analysis. The characterization results confirmed that Eleusine indica grass could be used for the production of sustainable fiber-reinforced polymer composites. [ABSTRACT FROM AUTHOR]

The present work includes the synthesis of zinc selenium telluride ZnSe1-xTex (0 ≤ x ≤ 1) ternary compound and its deposition in the form of thin films having thickness 200nm using thermal evaporation technique under high vacuum. The synthesized material ZnSe1-xTex thin films are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), UV-VIS-NIR, and Raman spectroscopic measurements. The structural measurements reveal that the deposited thin films of ZnSe1-xTex material are polycrystalline, whose crystallinity decreases with concentration of tellurium material in thin films. The morphology measurement of films shows that the surface of films is smooth and particles are approximately spherical. The optical band gap estimated from the optical transmission spectra of the films is found to decrease with tellurium concentration. Peak shift is found towards red region with tellurium concentration in the films in Raman spectroscopic measurements. The obtained results are analyzed for application of ZnSe1-xTex thin films. [ABSTRACT FROM AUTHOR]

In the present work, characterization studies are carried out on liquid crystalline (LC) p-n-propoxy benzoic acid (3oba), p-n-propyl benzoic acid (3ba) and the mixture of these two benzoic of acids dispersed with low weight concentrations of ZnO nanoparticles (nps). The existence of ZnO nps in above LC compounds are studied by scanning electron microscope and X-ray diffraction techniques. The LC phase transition temperatures of the compounds with the dispersion of ZnO nps are measured using polarizing microscope (POM) and differential scanning calorimeter (DSC). The nematic phase transition temperatures of 3ba, 3oba and mixture of 3ba and 3oba obtained from POM and DSC found to decrease with increase in the dispersion of various weight concentrations of ZnO nps. The birefringence studies are carried out for these compounds at different wavelengths (400, 500, 570, and 635 nm) with the dispersion of ZnO nps with increasing in weight concentrations (1, 1.5, 2 and 2.5 wt%) using modified spectrometer and the orientational order parameter 'S' of corresponding LC nanocomposites is measured from different optical methods viz., Kuczynski internal field model, Vuks isotropic model and effective geometry model. Among the three models the order parameter found to increase due to the strong alignment of LC molecules with the ZnO nps. The refractive indices measured at different wavelengths are fitted with two and three coefficient Cauchy's model. For high birefringence LCs three coefficient Cauchy's model is favorable than two coefficient model and vice versa. The results obtained are compared and discussed. [ABSTRACT FROM AUTHOR]

The updated Nanostructure materials and nano-technological tools are predicted to enable the synthesis polymer-inorganic composites to manufacture higher qualified membranes possess attractive physical and chemical properties with high performed sensitivity and selectivity. In this study carboxylated poly (vinyl chloride) (CPVC), CPVC/silver and CPVC/palladium nanocomposites membranes were prepared. Samples from the CPVC/Ag and CPVC/Pd nanocomposites films were irradiated with gamma doses in the range 25-150 kGy. The structural modifications in the gamma-irradiated nanocomposite samples have been studied as a function of dose using different characterization techniques such as X-ray diffraction XRD, UV spectroscopy, color difference studies, Thermogravimetric analysis TGA and scanning electron microscope SEM. The results indicate that the gamma irradiation in the dose range 50-150 kGy led to a more compact structure of both CPVC/Ag and CPVC/Pd nanocomposite films, which resulted in an improvement in its thermal stability with an increase in the activation energy of thermal decomposition and amorphous phase. It is worth mentioned that the nano-palladium is more effective than nano-silver composite membranes in stabilizing the CPVC. In addition, the results of color difference measurements indicated that both the CPVC/Ag and CPVC/Pd nanocomposite films acquire color under gamma irradiation up to 150 kGy, but the response of CPVC/Ag to color changes is higher. For this reason, the CPVC/Ag nanocomposite film was chosen to be a subject for the further study to investigate the effect of gamma irradiation on its optical and microscopic properties. it is found that the gamma irradiation reduces the optical energy gap that could be attributed to the increase in structural disorder of the irradiated CPVC/Ag nanocomposite due to crosslinking. [ABSTRACT FROM AUTHOR]

Aluminum-based metal matrix composites (AMCs) play a vital role for potential applications in aerospace and automotive industries. This paper explores the experimental analysis of a composite with aluminum LM4 alloy as the matrix and tungsten carbide (WC) as the reinforcement material. The composite specimens were fabricated by the stir casting process. The reinforced ratios of 5, 10 and 15 wt.% of WC particulates were stirred in molten aluminum LM4 alloy (AALM4). Once the composite is solidified, the specimens are prepared to the required ASTM dimensions and tested for various mechanical properties such as tensile strength, impact strength and hardness. Moreover, the tribological behavior of the composite was studied using the pin-on-disc wear test apparatus. X-ray diffraction (XRD) analysis was conducted to analyze the various elements present in the composites. Finally, the scanning electron microscope (SEM) analysis reveals the uniform distribution of WC particles in Aluminum LM4 alloy matrix. The improvement in mechanical properties - hardness, impact strength and tensile strength - was achieved for the increase in the addition of wt.% of WC particles in the LM4 matrix. The decrease in mass loss was observed for the composite containing 15 wt.% of WC during the wear test among the various composites tested. [ABSTRACT FROM AUTHOR]

Composite films of TiN/Ni3N/a-Si3N4were synthesized using the Mather-type plasma focus device with varying numbers of focus deposition shots (5, 15, and 25) at 0° and 10° angular positions. The composition and structural analysis of these films were analyzed by using Rutherford backscattering (RBS) and X-ray diffraction (XRD). Scanning electron microscope and atomic force microscope were used to study the surface morphology of films. XRD patterns confirm the formation of composite TiN/Ni3N/a-Si3N4films. The crystallite size of TiN (200) plane is 11 and 22 nm, respectively, at 0° and 10° angular positions for same 25 focus deposition shots. Impurity levels and thickness were measured using RBS. Scanning electron microscopy results show the formation of net-like structures for multiple focus shots (5, 15, and 25) at angular positions of 0° and 10°. The average surface roughness of the deposited films increases with increasing focus shots. The roughness of the film decreases at higher angle 10° and the films obtained are smoother as compared with the films deposited at 0° angular positions. [ABSTRACT FROM AUTHOR]

In this paper, we present the result of TiN nanocrystalline deposition on SS316L, using a 4 kJ plasma focus (PF) device for 10, 20, and 30 focus shots. The effect of different number of focus shots on micro-structural changes of thin film is characterized by field emission scanning electron microscope. Existence of grains in different size confirms the formation of TiN nanocrystals on the surface of SS316L substrate. X-ray diffraction (XRD) reveals the formation of a nanocrystalline titanium nitride coating on the surface of SS316L samples. The crystalline size of TiN obtained from XRD data is strongly dependent on the number of focus shots. Thickness of the elements found on the surface of the treated sample that obtain by Rutherford backscattering spectroscopy (RBS) analysis is in the range of 150×1015−200×1015 atoms/cm2. All the existence elements in the coated samples are identified by Particle Induced X-ray Emission (PIXE) spectra. Investigation on the corrosion resistance of TiN coatings was performed using an electrochemical potentiodynamic polarization. Our results suggest that TiN nanocrystalline implantation with proper ion fluences using PF can significantly improve the corrosion resistance of SS316L. [ABSTRACT FROM AUTHOR]

Ba-M- and Sr-M-type hexagonal ferrites have been prepared via a sol–gel route, and the effects of adding different amounts of polyvinyl pyrrolidone (PVP) into the sol solutions. The average crystallite, size, D and σ, was obtained as for Z13 = 22 ± 2 nm and Z13-2 = 16 ± 3 nm and for Z16 = 18 ± 7 nm and Z16-2 = 17 ± 5 nm by XRD. FT-IR and TG analysis were used to prove the presence of PVP on BaFe12O19 and SrFe12O19. Based on the TGA curves the mass losses of the samples are assessed as follows: Z13 ∼15%, Z13-2 ∼25%, Z16 ∼5%, and Z16-2 ∼10%. [ABSTRACT FROM PUBLISHER]

Pr3+ and Tm3+ (0.2 mol %) ions doped magnesium calcium bismuth titanate [(MgCa)2 Bi4Ti5O20] ceramics were synthesized by conventional solid state reaction method. The structural and morphological properties of prepared ceramic powders were studied by using XRD and SEM profiles. The elemental analysis and FTIR spectra of the prepared ceramics have been analyzed. Emission spectrum of Pr3+: (MgCa)2Bi4Ti5O20 ceramic powder has shown strong red emission at 614 nm (3P0 → 3H6) with an excitation wavelength λexci = 452 nm (3H4 → 3P2) and Tm3+: (MgCa)2Bi4Ti5O20 ceramic powder has shown blue emission at 477 nm (1G4 → 3H6) with an excitation wavelength λexci = 367 nm (3H6 → 1D2). [ABSTRACT FROM AUTHOR]

Zinc thin films were deposited onto porous silicon (PSi) substrates by dc sputtering using a Zn target. These films were then annealed under flowing (6 l/min) oxygen gas environment in the furnace at 600°C for 2 h. Porous silicon is used as an intermediate layer between silicon and ZnO films and it provides a large area composed of an array of voids. The PSi samples were prepared using photoelectrochemical method on n-type silicon wafer with (111) and (100) orientation. To prepare porous structures, the samples were dipped into a mixture of HF:ethanol (1:1) for 5 min with current densities of 50 mA/cm2, and subjected to external illumination with a 500 W UV lamp. The surface morphology and the nanorod structure of the ZnO films were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). We synthesized the ZnO nanorods with diameter of 80-100 nm without any catalysts or templates. The XRD pattern confirmed that the ZnO nanorods were of polycrystalline structure. The surface-related optical properties have been investigated by photoluminescence (PL) and Raman measurements at room temperature. Micro-Raman results showed that A1(LO) of hexagonal ZnO/Si(111) and ZnO/Si(100) have been observed at 522 cm-1 and 530 cm-1, respectively. PL spectra peaks are clearly visible at 366 cm-1 and 368 cm-1 for ZnO film grown on porous Si(111) and Si(100) substrates, respectively. The PL spectral peak position in ZnO nanorods on porous silicon is blue-shifted with respect to that in unstrained ZnO (381 nm). [ABSTRACT FROM AUTHOR]

Powder phosphors of CaLa1-xEuxAl3O7, CaLa1-xCexAl3O7 and CaLa0.99-xEuxCe0.01Al3O7, where x = 0.01, 0.03, 0.05 and 0.07, were prepared by a combustion method. The powders were well characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and photoluminescence techniques. Emission spectra of Eu3+-doped powder phosphors showed strong red emission at 613 nm (5D0 → 7F2); no concentration quenching was observed. Generally, Ce3+ acts as an efficient sensitizer when doped with other trivalent lanthanide ions. However, interestingly, in the CaLaAl3O7 powder phosphors, the addition of Ce3+ with Eu3+ exhibited an adverse effect-decreased photoluminescence intensity. The reasons for this behavior are discussed. [ABSTRACT FROM AUTHOR]

Conducting polypyrrole (PPY) polymer thin films, prepared by the electrochemical process, were irradiated with 50 MeV Li3+ and 90 MeV C6+ ions at different fluences, ranging from 1011 to 1014 ions cm-2. The structural and electrical properties of the swift heavy ions (SHI) irradiated films were analyzed using X-ray diffraction (XRD), Scanning electron microscope (SEM), and conductivity measurement methods. XRD analysis of SHI irradiated PPY films shows that the crystallinity of the PPY films increases with increasing fluences of lithium ions, but tends to become amorphous at higher fluence. Carbon ions irradiations lead to polymer destruction and simultaneous amorphization even at low fluence. The SEM studies of irradiated PPY films show systematic change in their surface morphologies. The surface was smoother at lower fluence but craters were observed at higher fluence. The surface conductivity of films increases with increasing fluence of lithium ions, which also turn to the virgin film conductivity at higher fluence. It was found that carbon ions do not much affect the surface conductivity of PPY. [ABSTRACT FROM AUTHOR]

HoAl-Al2O3/TiAl composites were fabricated by in-situ reaction synthesis using Al, Ti, TiO2 and Ho2O3 powders as raw materials. The effects of Ho2O3 content on the microstructure and mechanical properties of the composites were investigated. The phase constitution and microstructure of the composites were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results indicate that the ultimate phases of the composite are composed of TiAl and Ti3Al (matrix phases), and Al2O3 and HoAl (reinforced phases). Doping Ho2O3 alters the ratio of TiAl and T3Al and the microstructure of the composites, and the properties of the materials were changed accordingly. The mechanical property tests show that the addition of Ho2O3 can improve the properties of composites significantly the bending strength reaches 594 MPa and Vickers hardness reaches 4.76 GPa with 6 wt% Ho2O3. [ABSTRACT FROM AUTHOR]