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Complex oxides La 0. 9 7 Ba 0. 0 3 MnO3, La 0. 7 3 Ba 0. 2 7 MnO3 and La 0. 5 Ba 0. 5 MnO3 were synthesized and their structural properties were studied. The structural investigation of the samples is done by incorporating X-ray diffraction (XRD) and scanning electron microscope (SEM) technique at room temperature. The Rietveld method was successfully used for the analysis of the obtained diffraction spectra. It was determined that these compounds have a perovskite structure. Partial substitutions La→Ba do not disturb the ideal perovskite structure and the cubic crystal structure with the space group Pm-3m is preserved. Crystallographic parameters, lattice parameters and interatomic distances were determined for each compound. As a result of SEM studies, it was determined that the size of crystallites in LaxBa 1 − x MnO3 solid solutions ranged from 2 to 10 μ m. [ABSTRACT FROM AUTHOR]

CuO:ZnO nanocomposite photocatalyst with tunable ratios of CuO was synthesized using a low-temperature-assisted co-precipitation method, which is suitable for industrial-scale production. Analytical techniques, including XRD, FE-SEM, HR-TEM, FTIR, XPS and UV–Vis, were utilized to investigate the structure, morphological characteristics, chemical composition and optical properties of the CuO:ZnO nanocomposite. The XRD analysis reveals that the samples exhibit a single phase, characterized by a wurtzite hexagonal structure of ZnO and a monoclinic structure of CuO. The average crystal size changed from 37.3±8.8nm to 24.6±6.9nm when CuO varied from 0% to 5% in the CuO:ZnO nanocomposite. The scanning electron microscope (SEM) images reveal that the nanocomposite particles exhibit a high degree of uniformity, with an average size of approximately 50nm. HR-TEM shows the width of lattice plane families consistent with X-ray diffraction for CuO and ZnO materials. The ZnO exhibits a unique hexagonal shape. Furthermore, there is a slight correlation between the CuO fraction and an increase in grain size. FTIR analysis revealed the specific vibrational modes of ZnO and CuO at wavenumbers of 564, 619, 651, 673 and 488, 607cm−1, respectively. XPS shows secondary valences of Cu and Zn indicating the formation of CuO and ZnO while the high Ov peak indicates the presence of Oxygen defects in the crystal lattice. The absorption results clearly demonstrate the presence of two absorption edges corresponding to ZnO and CuO, as well as the broadening of the absorption spectrum of the nanocomposite sample up to a wavelength of 840nm. The photocatalytic degradation of RhB yielded remarkable outcomes, as the concentration of RhB declined by 98.6% after 20min of illumination using a CuO:ZnO (3:97) nanocomposite. The photocatalytic efficiency is significantly influenced by changing the CuO ratio in CuO:ZnO nanocomposites. This can be attributed to the tradeoff between the effectiveness of the heterogeneous contact layer and the limited ability of CuO to catalyze photochemical reactions. Based on the scavenger test, hydroxyl and superoxide radicals are primarily responsible for the decolorization of RhB dye. Results of evaluating the reusability and stability of the material show that, after fifth recycling, the decomposition efficiency still reaches over 90% after 30min of illumination. [ABSTRACT FROM AUTHOR]

BiFeO3–BaTiO3 is a promising lead-free piezoelectric ceramic, exhibiting high Curie temperature and superior electrochemical characteristics. In this work, (1 − x) BiFeO3–xBaTiO3 (BF–xBT, x = 0. 2 6 , 0.28, 0.30, 0.32, 0.34, 0.36) ceramics were fabricated using the conventional solid-state reaction method through precise composition control. Multiple characterization techniques, including X-ray powder diffraction (XRD), scanning electron microscope (SEM), and electrical property testing systems, were applied to systematically examine the crystallographic structure, microstructure, as well as the dielectric, ferroelectric and piezoelectric properties of the BF–xBT ceramics. The XRD results confirm that all compositions exhibit a typical perovskite structure, transitioning from a single rhombohedral phase to a rhombohedral–cubic phase mixture as the BT content increases. SEM shows apparent core–shell microstructures in the ceramics. Notably, the results demonstrated that the BF–0.30BT ceramic exhibits the maximum piezoelectric constant ( d 3 3 ) ∼ 2 1 7 pC/N, while the BF–0.34BT ceramic displays the maximum converse piezoelectric constant (d 3 3 ∗) ∼ 3 2 3 pm/V, which highlights the suitability of BF–BT ceramics for high-performance piezoelectric applications. [ABSTRACT FROM AUTHOR]

In this study, analyses were carried out to investigate the structural, mechanical and electrochemical behaviors of untreated and bioglass (BG)-coated Ti45Nb materials. The samples were coated with a mixture of 63s BG powder and phosphate ester (PE) at concentrations of 0.2, 0.4, 0.8, and 1 g using the electrophoretic deposition (EPD) method. Then, the structural, mechanical, and electrochemical properties of the untreated and coated samples were determined and characterized by using X-ray diffraction (XRD) and scanning electron microscope (SEM) devices. It was concluded that the 0.2 g coating provided resistance to corrosion for the Ti45Nb material more effectively than the others did. [ABSTRACT FROM AUTHOR]

This study reports the synthesis of quaternary copper nickel tin sulfide (Cu2NiSnS4) thin films using two different strategies and their physico-chemical properties. The first strategy includes co-evaporation of copper–nickel-tin–sulfur (CNTS) followed by sulfurization and the secondstrategy includes co-evaporation of copper–nickel–tin (CNT) followed by sulfurization. The X-ray diffraction (XRD) study reveals that the film prepared by both strategies has a polycrystalline Kesterite structure. The scanning electron microscope (SEM) analysis shows densely covered CNTS all over the substrate. The optical analysis of both CNTS films exhibits absorption of visible wavelength in an optimal range. The CNTS thin film synthesized using thermal evaporation technique followed by sulfurization has the potential to exhibit better photovoltaic properties for solar cell applications. [ABSTRACT FROM AUTHOR]

Potassium chloride (KCl) nanoparticles were synthesized by ball milling technique with different milling time. The effect of milling time on structural and optical properties was investigated. The structural properties of the purchased samples are characterized by Raman spectroscopy, scanning electron microscope and X-ray diffraction techniques. The Raman spectroscopy of the KCl hints at an excellent alloying behavior of those compounds and a preferred crystal structure for certain composition. The optical band is calculated by analyzing the spectral behavior of the absorption coefficient in the absorption region which revealed direct transitions. The value optical band increases (4.02–5.11 eV) with increasing milling time (0–15 h) due to quantum confinement after the ball milling process. The refractive and absorption indices were calculated for all samples. The model of Wemple–DiDomenico was used to calculate the dispersion parameters. The nonlinear susceptibility of the third order and the nonlinear refractive index were calculated by linear optical parameters using the generalized Miller rule. Mechanical milling for different milling times (0, 5, 10 and 15 h) by a planetary ball mill with zirconium oxide balls has been carried out for milling KCl. The images of as-purchased KCl have regular uniformly grains distributed like cubic particles with size of around 10 μm. By increasing the milling time to 15 h, these individual regular shapes form a smaller reasonably dense having a size less than 500 nm. [ABSTRACT FROM AUTHOR]

Fe3O4 nanoparticles coating with poly dimethyl diallyl ammonium chloride (Fe3O4/PDDA) as novel magnetic adsorbents were synthesized with chemical co-precipitation method to study the removal capacity of organic phosphonates from aqueous solution. The as-prepared magnetic absorbents were characterized for the morphology, material structure and surface properties by SEM, TEM, FT-IR, XRD, TGA and BET. HEDP was employed as a common organic phosphonate to investigate the adsorption performance. Substantial quaternary ammonium groups existing on the surface of Fe3O4/PDDA could enhance the absorption of HEDP with electrostatic attraction. In the optimum condition (4 mg adsorbent dosage, 11.0 pH, 36 mg/L HEDP solution and 120 min adsorption time), the maximum adsorption capacity ( q m ) for HEDP could reach 254.86 mg/g. The kinetic study revealed that the adsorption process followed the pseudo-second-order model. The adsorption isotherm fitted closely to the Freundlich model. The as-prepared magnetic adsorbents exhibited notable reusability in some cycles and were easily separated from the solution with the external magnetic field. These as-prepared Fe3O4/PDDA nanoparticles have the potential as an environmental-friendly adsorbent for organic phosphonates removal from waste-water. Fe3O4 nanoparticles modified with PDDA have been successfully fabricated by the chemical co-precipitation method. The PDDA on the surface of particles provided substantial quaternary ammonium groups which enhanced the absorption of HEDP from aqueous solutions with electrostatic attraction. These magnetic nanoparticles exhibited good reusability in several cycles. [ABSTRACT FROM AUTHOR]

In this study, a series of LaMnO3–diamond composites with varied LaMnO3 mass contents supported on micro-diamond have been synthesized using a sol–gel method. The as-prepared composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy and the Fourier transform infrared spectra (FTIR). Meanwhile, the photocatalytic performances were also tested by photoluminescence (PL) spectroscopy, ultraviolet–visible diffuse reflection spectra (UV-Vis DRS) and the degradation of weak acid red C-3GN (RC-3GN). Results show that the peak position of LaMnO3 is shifted to low angle after the introduction of diamond, and perovskite particles uniformly distributed on the surface of diamond, forming a network structure, which can increase the active sites and the absorption of dye molecules. When the mass ratio of LaMnO3 and diamond is 1:2 (LMO–Dia-2), the composite shows the most excellent photocatalytic activity. This result offers a sample route to enlarge the range of the application of micro-diamond and provide a new carrier for perovskite photocatalysts. LaMnO3–diamond composites supported on micro-diamond were synthesized using a sol–gel method. LaMnO3 nanoparticles are well-distributed on the surface of diamond and forming a network structure, which can increase the active sites and the absorption of dye molecules. This result offers a sample route to enlarge the range of application of micro-diamond, and provides a new carrier for perovskite photocatalysts. [ABSTRACT FROM AUTHOR]

In this study, in order to obtain the optimal fabricating condition, the influences of heating temperature and time on the fabrication of zinc oxide (ZnO) nanowires are clarified. During this process, the synthesis and scanning electron microscope (SEM) images of ZnO nanostructures, produced by direct heating of metallic zinc, are presented. Besides, the SEM images and X-ray diffraction (XRD) patterns of products under different conditions are compared to analyze the surface morphology and composition of products. In the final observation, the best diameters of ZnO nanowires are achieved as 60–70 nm, which can be successfully applied as a substrate in Raman measurement. The optimal temperature is 450∘C, as well as the optimal time is 40–50 min. [ABSTRACT FROM AUTHOR]

The process of conversion from -Ga2O3 single crystal to gallium nitride (GaN) in an atmosphere of NH3 by chemical vapor deposition is investigated. The surface morphology and microstructure of the GaN nanoparticles are observed by scanning electron microscope, which indicates that the growth of GaN is via the Volmer-Weber mechanism. The -Ga2O3 is firstly evaporated at high temperature to form the porous layer, followed by the surface-defect induced GaN nucleation formation. The crystalline structure and epitaxial relationship of the GaN nanoparticles are investigated by X-ray diffraction (XRD) via -, showing GaN (0002) and (0004) diffraction peaks in the XRD spectra. It is concluded that the polycrystalline GaN film with hexagonal structure has a strong c-axis preferential orientation. [ABSTRACT FROM AUTHOR]

The effect of rare earth element neodymium (Nd) addition on the microstructure and martensitic transformation behavior of NiTiNd ( = 0, 0.1, 0.3, 0.5 and 0.7 at.%) shape memory alloy was investigated by scanning electronic microscope, X-ray diffraction and differential scanning calorimetry. The results show that the microstructure of Ni-Ti-Nd ternary alloy consists of NiNd phase, NiTi2 and the NiTi matrix. A one-step martensitic transformation is observed in the alloys. The martensitic transformation temperature Ms increases sharply increasing 0.1-0.7 at.% Nd content is added. [ABSTRACT FROM AUTHOR]

In the present study, the effects of carburization treatment on the microstructure and corrosion property of medium-carbon steels (40Cr) were investigated by means of X-ray diffraction (XRD), electron microprobe analyzer (EMPA), optical microscope (OM), scanning electron microscope (SEM), transmission electron microscope (TEM) and electrochemical corrosion, respectively. It was found that the microstructures beneath the surface were refined and a smooth transition microstructure from the surface to the core was observed in carburized samples. The fine plate-like but not granular carbide precipitation (Cr7C3) was observed in carburized sample by heat-treatment. The carburized specimens exhibited some effectiveness in the improvement of hardness and a smooth transition hardness profile. Corrosion resistance of 40Cr was improved by carburization treatment, resulting in the higher self-corrosion potential and the lower self-corrosion current density. [ABSTRACT FROM AUTHOR]

Aluminum oxide (Al2O3) thin films with Al2O3 buffer layer were deposited on Si (100) and Si (111) substrates using RF magnetron sputtering of Al2O3 target in Ar atmosphere. The synthesized films were then annealed at the temperature of 400C, 600C and 800C in nitrogen (N2) environment for 6h. Structural properties and surface morphology are examined by using X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) and Atomic Force Microscope (AFM). XRD analysis indicated that different orientation of Al2O3 were formed with different intensities due to increase in the annealing temperature. From FESEM cross-section analysis results, it is observed that the thickness of films were increased as the annealing temperature increased. EDX analysis shows that the concentration of aluminum and oxygen on both the Si substrates increased with the increase in annealing temperature. The surface roughness of the films were found to be decreased first when the annealing temperature is increased to 400C, yet the roughness increased when the annealing temperature is further increased to 800C. [ABSTRACT FROM AUTHOR]

In this work, plasma electrolytic oxidation (PEO) ceramic coatings were prepared on magnesium AZ31B alloy. Various electrolyte solutions including phosphate, aluminate and silicate as additives and NaOH Na2SiF6 as constant agent were used to prepare the coatings. Influence of the additives on chemical composition and structure of the PEO coatings were examined by means of scanning electron microscope (SEM) and XRD. From structural analysis it was found that coatings prepared in the aluminate-based electrolyte have the best structural features. Microhardness and tribological characteristics of the PEO coatings were investigated using Vickers hardness test and pin-on-disc test. Microhardness for aluminate-based coating was found to be 1169.63HV while those for silicate-and phosphate-based coatings were 1093.42HV and 285.91HV, respectively. Wear rate of the aluminate-based coating was found to be lowest than all other coatings having a value of mg/Nm. [ABSTRACT FROM AUTHOR]

In this paper, we have investigated the effect of Mn doping on the electrical properties of ZnO thin films. ZnO thin films with different amounts of Mn concentrations (0, 5, 10 and 15 mol.%) were prepared by spray pyrolysis technique. The crystal structure was examined by X-ray diffraction (XRD) analysis. XRD patterns showed that all the samples were crystallized in wurtzite structure while a decrease in crystallinity and switch in preferential orientations were observed in Mn-doped thin films comparing to undoped ZnO. The element composition of all thin films was detected by energy dispersive X-ray (EDX). The surface morphology of the films was investigated using field emission scanning electron microscope (FESEM) and optical properties were studied using UV-vis spectroscopy. UV-vis study revealed that the band gap blueshifts with the increase in Mn content and increases with the increase in Mn concentration. The resistivity and activation energy were measured at room temperature and ranging from 373 K to 573 K. Comparing to undoped ZnO thin film, the resistivity of Mn-doped ZnO films increased because of different parameters such as increasing barrier height energy and reducing the oxygen deficiency. [ABSTRACT FROM AUTHOR]

The composite coatings were fabricated by laser cladding Al/TiN pre-placed powders on Ti–6Al–4V substrate for enhancing wear resistance and hardness of the substrate. The composite coatings were analyzed by means of X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). The sliding wear tests were performed by MM200 wear test machine. The hardness of the coatings was tested by HV-1000 hardness tester. After laser cladding, it was found that there was a good metallurgical bond between the coating and the substrate. The composite coatings were mainly composed of the matrix of β-Ti (Al) and the reinforcements of titanium nitride (TiN), Ti3Al, TiAl and Al3Ti. The hardness and wear resistance of the coatings on four samples were greatly improved, among which sample 4 exhibited the highest hardness and best wear resistance. The hardness of the coating on sample 4 was approximately 2.5 times of the Ti–6Al–4V substrate. And the wear resistance of sample 4 was four times of the substrate. [ABSTRACT FROM AUTHOR]

Ba4LaTi0.3Sn0.7O15 ceramic was prepared through conventional solid state mix oxide route followed by characterization using X-ray diffraction (XRD) and scanning electron microscope (SEM) for phase and microstructural investigation. The dielectric properties at low and microwave frequencies were measured using LCR meter and vector network analyzer. XRD results revealed single phase ceramics and the microstructure was comprised of compact grains with size ranging from 4–12 μm. The lattice parameters refined by the least squares method were a = b = 5.7680(2) Å, c = 11.7491(6) Å, V = 337.81 Å3 and Z = 1. Optimum properties i.e., εr~44.6, Qufo~15, 500 GHz and τf~2.05 ppm/°C were achieved for Ba4LaTi0.3Sn0.7 Nb3O15 ceramic sintered at 1475°C for 4 h. [ABSTRACT FROM AUTHOR]

The decomposition of goethite and goethite/siderite concentrates into hematite with thermal modification was studied through the measurements of X-ray diffraction (XRD), scanning electronic microscope (SEM) and thermal gravimetric analysis (TGA). The experimental results showed that goethite decomposed into hematite directly at around 300°C without any intermediate phase and the decomposition of siderite completed at 500°C. Nanoscale granular structures were observed in the thermally treated products. It deserves highlighting that the decomposition processes proceeded from surfaces into bulks. [ABSTRACT FROM AUTHOR]

This work is based on the dry sliding wear of the MgAl2C2-TiB2-FeSi composite coating deposited on a pure using a laser cladding technique. Scanning electron microscope images indicate that the nanocrystals and amorphous phases are produced in such coating. X-ray diffraction result indicated that such coating mainly consists of MgAl2C2, Ti-B, Ti-Si, Fe-Al, Ti3SiC2, TiC and amorphous phases. The high resolution transmission electron microscope image indicated that the Ti-B nanorods were produced in the coating, which were surrounded by other fine precipitates, favoring the formation of a fine microstructure. With increase of the laser power from 0.85 kW to 1.00 kW, the micro-hardness decreased from 1350 ~ 1450 HV0.2 to 1200 ~ 1300 HV0.2. The wear volume loss of the laser clad coating was 1/7 of pure Ti. [ABSTRACT FROM AUTHOR]

Nanoparticle Lead sulfide was synthesized via simple chemical method and deposited on glass substrates at different substrate temperatures by thermal evaporation technique. The synthesized nanoparticle was analyzed and confirmed by X-ray diffraction (XRD), Scanning electron microscopy SEM with EDX and thermogravimetry. The structural, optical, morphological and electrical properties of the deposited films were studied using XRD, UV-Vis, Raman, SEM with EDX, atomicforce microscopy AFM and Hall Effect measurements. The thickness of the deposited samples was measured using thickness profilometer. The Raman shift in the peak occurs toward lower energy with increasing substrate temperature deposited lead sulfide. The Z-scan study with open aperture was carried out at 532 nm using 5 ns laser pulse on the deposited films which shows that nonlinear absorption arises from saturable absorption process. The deposited film exhibits p-type conductivity in Hall measurement. [ABSTRACT FROM AUTHOR]

Styrene-doped ZrLaOy nanostructures were obtained by sol-gel method low-temperature synthesis. The nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM) and transmission electron microscopy (TEM) techniques. The observation using SEM and TEM revealed that the ring-shaped nanostructures were very uniform. Further characterization using XRD disclosed that the cohesion of the samples was controllable with annealing temperatures in the range of 800-1500° C. Cohesion property was investigated for the samples. The cohesion increased when increasing the annealing temperature. This was linked to the reinforcement of the oxygen bound on the ZrLaOy nanostructures The shape of nano-structures showed a transformation from a ring-shaped growth mode to a hole-surfaced growth mode with increasing annealing temperature. The styrene-doped ZrLaOy nano-structures with controllable crystallinity will have great potential for various applications in fuel, cells, batteries, electronics devices and chemical sensors. [ABSTRACT FROM AUTHOR]

The Fe304@C core/shell microspheres were fabricated via a two-step process. Fe304 micro-spheres were firstly prepared, and Fe304@C core/shell microspheres were subsequently fabricated using glucose as a carbon source by a hydrothermal route, in which the thickness of the carbon coating was about 20 nm. The resulting products were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectra (FTIR). The Nitrogen adsorption--desorption isotherms reveal their mesoporous structure and larger BET surface area (62.3 m²g-1). The Fe304@C core/ shell microspheres possess ferromagnetism and high saturation magnetization (39.2 emu g-1). Bovine hemoglobin (BHb) was used as a model protein to test the adsorption and desorption properties of the Fe304@C core/shell microspheres. The capacity for BHb adsorption was more than 71.3 mg/g. According to the values obtained in the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay the Fe304@C core/shell microspheres show a low toxicity. Therefore, the prepared Fe304@C core/shell microspheres are of great significance for guided site-specific drug delivery. [ABSTRACT FROM AUTHOR]

Nano nalidixic acid was prepared by ultrasonic method in carbon tetrachloride. Nano nalidixic acid (quinolone antibiotic) was characterized by X-ray diffraction (XRD), infrared spectroscopy (IR) and scanning electron microscope (SEM). The antibacte-rial activities of nano nalidixic acid were tested against microorganisms and compared with the microscale drug. The results show that nano nalidixic acid has good inhibitory properties against two Gram-positive species, Staphylococcus aureus and Bacillus sub-tilis. Nano nalidixic acid also showed good antifungal activity against Candida albicans. Nano nalidixic acid can be injected into the human body as a decontaminating agent to prevent the growth of harmful microorganisms more effectively than the micro-sized drug. [ABSTRACT FROM AUTHOR]

For the first time, pyromilling synthesis for production of nanocrystalline titanium carbide was presented in this research. Raw materials containing stoichiometric ratio of titanium and carbon were milled and heated simultaneously. Samplings were done at different times. Then, phase transformation, crystallite size and strain of samples were estimated by XRD technique. Microstructures of milled samples were studied by SEM and TEM. Results showed that by increasing temperature, milling time for synthesizing of titanium carbide was reduced. Crystallite size of milled samples were in nanometer scale which were reduced by increasing of milling time and decreasing of temperature while strain was intensified. Existence of created strain changed lattice parameter of synthesized titanium carbide from standard value. This study aims at presenting pyromilling synthesis as a new method for production of titanium carbide in nanometer scales. This method is based on simultaneous application of milling and heating processes. Titanium and carbon powder were milled in different times and temperatures. The results obtained from X-ray patterns showed that an increase in temperature entails a reduction in milling time for synthesizing titanium carbides. Moreover, it is proved that the size of synthesized carbide titanium crystals were in nanometer scale which were decreased by an increase in the milling time and a decrease in the temperature. [ABSTRACT FROM AUTHOR]

The controlled synthesis of one-dimensional Ag/Au nanocomposite chains with a length of several micrometers (up to 3 μm) was described in this paper. In this synthesis method, the artificial active membrane of celloidin is used and N2H4 ⋅ H2O acts as the reductive agent. The morphologies, structures and optical properties of the product were researched by TEM, SEM, EDS, XRD, and UV-Vis, etc. The synthesis mechanism of product was also postulated. Experiments proved that the synergic sterilization performances of Ag/Au nanocomposite chains were stronger than Ag/Au nanocomposite particles. [ABSTRACT FROM AUTHOR]

Tin oxide thin films were prepared via spray pyrolysis method. The structural and morphological properties of SnO2 thin films have been investigated using X-ray diffraction (XRD) and scanned electron microscope (SEM) analysis. The XRD pattern confirms the tetragonal rutile structure of SnO2 with preferential orientation along (200) plane. SEM image reveals the nanocrystalline nature of the SnO2 films. SnO2 thin films were subjected to electrochemical tests to study the supercapacitor behavior. Maximum specific capacitance of 168 F/g at a scan rate of 25 mV/s was obtained using 0.5 M KOH as the electrolyte. This is the highest value ever reported for spray deposited tin oxide thin films. [ABSTRACT FROM AUTHOR]

Laser cladding of the Fe3Al + B4C/TiN + Al2O3 pre-placed powders on the Ti-6Al-4V alloy can form the Ti3Al/Fe3Al + TiN/TiB2 composite coating, which improved the wear resistance of the Ti-6Al-4V alloy surface. In this study, the Ti3Al/Fe3Al + TiN/TiB2 composite coating has been researched by means of X-ray diffraction and scanning electron microscope. It was found that during the laser cladding process, Al2O3 can react with TiB2, leading to the formations of Ti3Al and B. This principle can be used to improve the Fe3Al + B4C/TiN laser-cladded coating on the Ti-6Al-4V alloy. Furthermore, during the cladding process, C consumed the oxygen in Fe3Al + B4C /TiN + Al2O3 molten pool, which retarded the productions of the redundant metal oxides. [ABSTRACT FROM AUTHOR]

The microstructures and mechanical properties of Ni50-xTi43+xAl6Mo1 (x= 0.5, 1, 1.5, 3.5, 5.5 and 7 at. %) alloys have been investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and compressive tests. We found that the variation of Ni/Ti ratio is the predominant reason for affecting the yield stress. The yield stress at room temperature of Ni-rich and Ti-rich alloys was higher than that of the equi-atomic alloy due to the strong solid solution hardening caused by the variation of Ni/Ti ratio. The size and volume fraction of Ti2Ni phase decreased with increasing Ni/Ti ratio. The yield stress at 600°C and 700°C increased with the increasing volume fraction of Ti2Ni phase due to the precipitation hardening effect. The precipitation hardening effect was weakened with increasing temperature. For the Ti-rich alloy deformed at 800°C, the yield stress deceased with the increasing of Ni/Ti ratio due to the reduced strength and unfavorable distribution of Ti2Ni. [ABSTRACT FROM AUTHOR]

Chemical bath deposition (CBD) and ultrasonic chemical bath deposition (US-CBD) of ZnS thin films from NH4OH/SC(NH2)2/ZnSO4 solutions have been studied. The influence of the ultrasonic vibration on properties of ZnS thin films has been investigated. The growth rate, structure, and properties of ZnS thin film deposited by different CBD techniques were studied using X-ray diffractometer (XRD), scanning electron microscopy (SEM), and atomic force microscope (AFM). The results show that the growth rate of US-CBD is slower than that of CBD. The XRD analysis of as-deposited ZnS films shows that the films are both cubic ZnS structure and the crystallinity of US-CBD ZnS film is higher than that of CBD ZnS film. SEM studies indicate that adhesion particles on the US-CBD ZnS surface are fewer than that on the CBD ZnS surface. Moreover, the film prepared by US-CBD is homogeneous and with high compactness. The rms roughness (Rrms) value of CBD ZnS film is higher than that of US-CBD. Transmission measurement shows that the optical transmittance of US-CBD ZnS is higher than that of CBD ZnS, and the optical transmittance is above 90% when the wavelength is over 470 nm. The band gap (Eg) values of the films deposited by CBD and US-CBD are 3.50 and 3.67 eV, respectively. [ABSTRACT FROM AUTHOR]

α-Fe2O3 nanoparticles were obtained by a mechanical alloying of micrometer-sized powder at different milling times. Samples were characterized by X-ray powder diffraction, scanning electron microscope (SEM), Mössbauer spectrometry, and vibrating sample magnetometer (VSM). A qualitative and quantitative phase analyses using the Rietveld method have been performed based on the XRD data. The results did not reveal any phase change during the milling. The average particle size decreases with a prolongation of milling times, while the lattice parameters, unit cell volume, and microstrain increase. Mössbauer measurement shows that there are two components, one nanometric and other micrometric. The magnetic hysteresis loops shows that the samples are typical of ferromagnet with superparamagnetic fraction in the material. [ABSTRACT FROM AUTHOR]

In this study, the effect of bismuth content on the crystal structure and morphology of bismuth silicate (BSO:Bi4Si3 O12) polycrystals were investigated with X-ray diffraction (XRD) analysis and scanning electron microscope (SEM). BSO materials have been successfully prepared by the solid-state reaction. The BSO phase was crystallized at 950°C for 12 h. In summary, 10% of excess bismuth was found to be the optimum composition with respect to crystallization, morphology, and grain size. [ABSTRACT FROM AUTHOR]

Aiming at the influence of substitution on ferroelectric behaviors, Nd and Mg/Mn cosubstituted bismuth titanate films, Bi3.15Nd0.85Ti2.97Mg0.03O12 (BNTMg) and Bi3.15Nd0.85Ti2.95Mn0.05O12 (BNTMn), have been prepared on Pt/Ti/SiO2/Si(100) substrates at 700°C by a chemical solution deposition technique, respectively. A series of comparisons including structures, surface morphologies, and ferroelectric properties of the as-prepared films were carried out by X-ray diffraction, scanning electron microscope, and a Radiant Technologies Precision Workstation for ferroelectric test system. It was found that the films possess preferred the (117) and (00l)-oriented polycrystalline structures, and the remnant polarization of BNTMg film is larger than that of BNTMn film and the coercive field of BNTMn film is lower than that of BNTMg film. The values of 2Pr and 2Ec of BNTMg and BNTMn are 28 μC/cm2 and 212 kV/cm, and 15 μC/cm2 and 175 kV/cm, respectively. The relevant physical mechanisms were pursued. [ABSTRACT FROM AUTHOR]

TiC-based wear resistant coating was prepared by plasma spraying using reconstituted composite powders doped with ultra-fine carbide. Phase composition and microstructure of as-sprayed coating were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) utilizing backscattered imaging mode (BSE), and electron probe micro-analysis. Wear test was performed by using a ring-on-block tester under dry sliding condition. Results show that the coating adheres well to the substrate and no delamination appears. TiC content underwent pronounced reduction because of oxidation, reaction, and physical loss. Reactions between TiC and Mo and probably between dissociated C and Mo lead to the formation of Mo2C. Wear resistance of NiCrMo–TiC coating is about 4–8 times higher than that of substrate under different applied force. This work shed light on the reconstitution of spraying powder doped with ultra-fine reinforce phase particles, and the present results are important for the preparation of nano-doped TiC-based coatings. [ABSTRACT FROM AUTHOR]

Bayerite sol is spun onto single crystal Si substrate, after synthesis and optimization, to obtain films of thickness ~ 0.2 μm. The deposited films are room temperature dried and then heated up to a temperature of 350°C in order to obtain Al2O3. Surface and structural changes, during heating, are observed with optical microscopy. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) are used for post-treatment analyses/characterization. The as-deposited and heated samples' surfaces are smooth as seen with optical and scanning electron microscope in case of optimized conditions. XRD patterns show the change from amorphous to crystalline behavior of these films when heated under various conditions. The most stable form of aluminum oxide, i.e. α-Al2O3, is obtained when samples are heated up to a temperature of as low as 350°C. The thin films are also deposited onto sodalime glass substrates in order to confirm Al2O3 formation through band gap probing. Photoconduction is used to find the energy band gap, which comes out to be 4.7 eV; lower value is correlated to the defect induced states in the band gap. [ABSTRACT FROM AUTHOR]

In this study, hematite (Fe2O3) and aluminum (Al) powder mixtures were mechanically alloyed in a high-energy shaker ball mill to synthesize the iron-alumina (Fe-Al2O3) nanocomposite powder. The structural changes and phase developments occurring during mechanochemical process were studied by X-ray diffractometery (XRD) and scanning electron microscopy (SEM). The results showed that mechanochemical reaction of Fe2O3 and Al completed after 3 hours of milling time in a nanocrystalline Fe and Al2O3 embedded form and further milling produced a Fe-Al2O3 nanocomposite powder. Kinetics consideration according to the calculated adiabatic temperature demonstrated the sudden displacement reaction during mechanical alloying that accord well with XRD results. Also, particle size decrease as well as crystallite size with increasing the milling time. [ABSTRACT FROM AUTHOR]

The effect of nano size Ag addition on the YBa2Cu3O7-δ (Y-123) system has been investigated. 2–15% weight of nano size Ag was added to the Y-123 system prepared by using the sol-gel-solid-state method. The phase purity was investigated by the powder X-ray diffraction method. Energy Dispersive X-ray Analysis (EDAX) was used to determine the distribution of nano Ag in the samples, and the microstructure was observed using a Scanning Electron Microscope (SEM). The transport critical current density was found to increase with increase in nano Ag content. [ABSTRACT FROM AUTHOR]

Synthesis of the precursors, using research grade materials and locally available facilities, is optimized in order to obtain a suitable sol for BaTiO3. The optimally synthesized BaTiO3 sol is then spun onto Cu substrates to obtain films of thickness ~0.5 μm. The deposited BaTiO3 films are heated up to a temperature of 300°C. Surface and structural changes, with heating, are observed by optical microscope, scanning electron microscope, atomic force microscope, and X-ray diffraction. The surface cracked in some cases but is generally uniform, as seen with SEM and AFM, in case of optimized conditions. The SEM images reveal large crystallites, which are correlated to the XRD observation of tetragonal perovskite structure of these sol–gel films. The AFM scan, however, shows an rms roughness of 35.6 nm for an area of 3 μm × 3 μm. Tetragonal perovskite BaTiO3 is obtained at a temperature of as low as 300°C. The dielectric constant and loss angle, in the 30 Hz–3 MHz range, are calculated at room temperature and up to 200°C. At high frequencies the dielectric constant (~290) and loss angle (~2 × 10-6) values indicate the usefulness of such films in electronic applications. The leakage current is also measured at room temperature and a conductivity of 2.0 × 10-15S/cm is obtained. [ABSTRACT FROM AUTHOR]

Synthesis of uniform nanocrystalline anatase TiO2 by sol–gel method was investigated using different thermal analysis (DTA), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and scanning electron microscope (SEM) techniques. Thermal treatment of the precursor at 350°C for 2 h in air results in the formation of nanocrystalline anatase TiO2 with the average crystal size of 21.5 nm. Quantitative analysis through energy dispersive X-ray spectroscopy (EDS) indicated that the atomic ratio of Ti:O ≈ 1:1 is close to the stoichiometric ratio of TiO2, leading to the evident fact that the prepared nanoparticles are indeed the TiO2 material. [ABSTRACT FROM AUTHOR]

Pb0.76-3x/2LaxCa0.24Mn0.02Ti0.98O3 (PLCT), x=0–0.08 (in steps of 0.02), ceramics were prepared by conventional mixed oxide technique. The samples were sintered at an optimized temperature of 1150°C. Phase and microstructural analysis were carried out using X-ray Diffraction (XRD) and scanning electron microscope (SEM) to study the effect of lanthanum on PCT ceramics. Both experimental and theoretical densities for all the samples were also determined. Phase analysis shows the single-phase material with tetragonal structure and the decrease in tetragonality is observed with the increase in the amount of lanthanum in the base composition. Detailed dilatometric investigations were performed in order to study the shrinkage behaviour and dominating shrinkage mechanism in the present system. [ABSTRACT FROM AUTHOR]