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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]

Transparent conductive oxide (TCO) thin films are highly sought-after for their unique characteristics of conducting electricity and transmitting visible light, making them ideal conductive coating materials for electronic devices. We carried out a comprehensive analysis of the deposition, optical, electrical, and structural properties of ITO and Ag/ITO thin films on glass substrates in this study. The weight ratio of the deposited metals was 1:10, 2:10, and 4:10 wt.% (Sn:In) for ITO films and 1:1:10 wt.% (Ag:Sn:In) for Ag–ITO film. The films were annealed at 300°C using a program controller furnace. We employed infrared cameras to analyze the surface temperature profiles of these thin films under external voltage supply. We also investigated the resistivity behavior of both ITO and Ag–ITO films, analyzing them with regard to Mott's variable range hopping (VRH) model and the fluctuation-induced tunneling model. Scanning electron microscope images revealed that adding Ag increased the grain size of ITO thin films. The average grain size for ITO thin film was determined as 186 nm, while it was found to be 270 nm for Ag–ITO thin film. Furthermore, incorporating Ag into the ITO thin film resulted in a reduction of 21.5% in transmittance over the complete visible range of the electromagnetic spectrum when compared to the ITO thin film without Ag as measured by ultra-visible spectrophotometer. The figure of merit was obtained as 0. 3 4 4 × 1 0 − 3 Ω − 1 for ITO and 0. 0 5 2 4 × 1 0 − 3 Ω − 1 for Ag–ITO thin films. However, the resistance of the ITO thin film was calculated to be 9.58 k Ω , while that of the Ag–ITO film was found to be 6.99 k Ω. The ITO thin film that included Ag exhibited a lower electrical resistivity due to the larger grain size caused by doped Ag atoms in the structure, leading to less electron scattering at the grain boundaries and a resulting decrease in resistivity as determined by four-point probe system. Thermal imaging camera measurements revealed that the surface temperature of the ITO thin film decreased with the addition of Ag under high voltage application, but not under low voltage. When a voltage of 350 V and 250 V was applied to the thin films, the ITO film exhibited a surface temperature of 73.9°C and 50.4°C, whereas under identical conditions, the Ag–ITO film showed a surface temperature of 62°C and 44.1°C, respectively. Furthermore, both films exhibited exponentially increasing surface temperature behavior under a certain voltage, suggesting that they have potential for transparent heaters and high-voltage/low-current applications. [ABSTRACT FROM AUTHOR]

Shape memory alloys (SMAs) are potential materials in various areas such as engineering and medicine, and their applications are being studied for practical use. SMAs show competence in their main material properties in response to their working environment or external stimuli. Machining of NiTiCu10 SMAs is difficult using traditional machining because of their wide-ranging mechanical properties like high toughness, strength, and sensitivity to phase transformation temperature. Nonconventional machining methods such as electro-discharge machining (EDM) are suitable for effective machining SMAs. The work material NiTiCu10 SMA has been used in this study, and processed using the vacuum induction melting (VIM) technique. The addition of copper leads to increase in the martensitic transformation temperatures. This paper focuses on the electro-discharge drilling (EDD) of NiTiCu10 SMA using copper tool electrode. Experimental analysis of performance criteria has been evaluated by conducting experiments following one factor at a time (OFAT) approach. Machining features such as material removal rate (MRR), tool electrode wear rate (TEWR), and surface roughness (SR) have been studied by considering pulse current ( I p ), gap voltage ( V g ), pulse on time ( T on ), pulse off time ( T off ), and rotational speed of tool electrode (N). Experimental results have shown that machining at the highest I p of 12 A yields the highest MRR with the value of 4.077 mm3/min, whereas mcahining at T on of 15 μ s yields the lowest TEWR with the value of 0.031 mm3/min. The lowest SR is 2.8 μ m achieved at the lowest T on of 15 μ s. Surface morphology is significant in quality evaluation in the manufacturing, and building industries because it directly determines the mechanical performance of parts, and the service life of products. Morphological investigation via scanning electron microscope (SEM) has confirmed the formation of craters, debris, microcracks, and resolidified layers. The benefit of this study has been that we have been able to select the range of significant control factors, and predict their levels, for decisive experimentation. [ABSTRACT FROM AUTHOR]

This paper presents a detailed synthesis method by solid-state reaction route and typical characterization (structural, microstructural, dielectric, impedance, modulus, and optical properties) of a double perovskite material Bi2FeMn 0. 9 Ce 0. 1 O6. An orthorhombic crystal structure having an average crystallite size of 32.2 nm is suggested by X-ray diffraction data (XRD). Scanning electron microscope (SEM) micrograph detects the presence of cylindrical nanorod-shaped distinct grains and well-defined grain boundaries in this material and the average grain size is 5.82 μ m. Furthermore, the purity and the presence of all constituent elements in the material were confirmed from energy dispersive X-ray (EDX) analysis and color mapping. Dielectric, impedance, modulus, and AC conductivity properties are studied within the temperature range of 25–500∘C and frequency range of 1 kHz to 1 MHz. The high dielectric constant at a low-frequency zone and low dielectric loss found in this material make it a promising candidate for better energy-storing devices. The negative temperature coefficient of resistance (NTCR) behavior is observed from the impedance study. The non-Debye relaxation is detected in the modulus study. The semiconducting nature of this material is verified by semicircular arcs observed in both Nyquist and Cole–Cole plots. The thermally activated conduction mechanism is confirmed by an AC conductivity study. The existence of Bi–O, Fe–O, Mn–O and Ce–O stretching vibrations are observed from the FTIR study and explain the presence of all constituent elements in the sample. The bandgap energy of 1.7 eV is calculated from UV-DRS analysis and hence this material can be used for advanced optoelectronic and photovoltaic applications. [ABSTRACT FROM AUTHOR]

The machinability of aluminum alloy (Al-6082) has the scope of enhancement by integrating Friction Stir Processing (FSP) with tool geometry, tool shape and different tool materials. In this research, the role of tool pin shape has been studied by experimenting on various tool shapes (square, hexagonal and octagonal) with the aim of machinability improvement. In FSP, the tool rotation speed is 930rpm and tool travel speed is 26mm/min. The specimens have undergone tensile, microhardness and microstructure testing using optical microscope and scanning electron microscopy. The percentage elongation has been increased from 15% to 29% in the case of the octagonal-shaped tool pin; similarly, the (Vickers’) microhardness value is 14.6% higher than the square- and hexagonal-shaped tool pins. Among these tool pin shapes, the octagonal-shaped tool pin succeeded in providing the best-in-class machinability performance on Al-6082 T6 alloy with FSP. It may unveil the newer scopes of FSP on Al-6082 for automotive components assembly and other similar applications. [ABSTRACT FROM AUTHOR]

In this study, a cladding-modified fiber-optic sensor is reported for NO2 gas detection. Monitoring the purity of air is the need of the hour, with the growing technologies. Hence, in this work, Ag-doped CdS is coated over the cladding-removed region of 3cm length by Chemical Bath Deposition (CBD) which acts as the gas-sensing medium. Ag–CdS is coated over four fibers each with a different coating duration of 10min, 20min, 30min and 40min. Characterization of Ag–CdS is done by Scanning Electron Microscope (SEM), UV-visible absorption spectroscopy and UV-visible reflectance spectroscopy. The spectral response for different concentrations of NO2 is studied on the four fibers separately, and it is analyzed and compared. The minimum detection limit is 100ppm and the response time is 10min. Out of the four fibers, Ag–CdS-30 exhibited the best response with a sensitivity of 15.5%. The results are compared with cladding-modified fiber coated with CdS, which was reported previously. The effect of Ag-doping is analyzed. [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]

The outcome of this research paper is to investigate the room and hot corrosion behavior of Al-10Ni-4Co-x multi-walled carbon nanotube (MWCNT) composites processed through Powder Metallurgy (P/M). The secondary particle MWCNT content was varied as 0.5, 1.0 and 1.5wt.%, respectively. The fabricated composites were characterized using a Scanning Electron Microscope (SEM). The corrosion behavior of the composites was analyzed using Tafel polarization. After polarization, the corroded surfaces were analyzed using SEM. The high temperature corrosion behavior was also investigated and found that the corrosion rate of 3.9025 mpy for 90Al-10Ni-4Co composite and 4.9025 mpy for 85Al-10Ni-4Co-1.0MWCNT composite. The results indicated that 84.5Al-10Ni-4Co-1.5MWCNT composite possessed better corrosion resistance than other composites. Various elements including Na, Cl, Al, Ni, Co, Mg, Si and O were observed. It reveals that Na+ and Cl− ions react well with Ti. Hot corrosion studies clearly demonstrated that after the 50 h test, the samples with MWCNT inclusion exhibited improved corrosion resistance. The 85Al-10Ni-4Co-1.0MWCNT composite showed a mass change of 0.01870mg which was 5% lower than 90Al-10Ni-4Co composite. [ABSTRACT FROM AUTHOR]

This paper outlines the TIG welding process without using active flux for 4 mm-thick plates of duplex stainless steel (DSS 2205) and austenitic stainless steel (SS 304L). It also provides the properties and behavior analysis of weldments. Complete penetration is achieved with multi-pass welding. The microstructure is examined using an optical microscope (OM) and a scanning electron microscope (SEM). It was used to report on the differences between the unpolished zone and the heat-affected zone (HAZ) in weldments. A Vickers hardness tester (HV scale 10) was used to assess the weldment's hardness. Tensile and bend failure were among the mechanical properties exhibited by the parent metals of DSS2205, SS304L, and dissimilar junctions. The findings demonstrated shallow gaps in the surface area and a greater ultimate tensile strength of 600 MPa for DSS similar welding. However, compared to other similar weldments, dissimilar weldments exhibit superior performance in bending conditions. [ABSTRACT FROM AUTHOR]

An atmospheric plasma spray deposition process was adopted for coating regular-shaped, Stellite 6 powder directly on a rolled 3mm size AISI 304 austenitic grade stainless steel substrate without any intermediate bond layers. Coating thickness as measured in a scanning electron microscope was obtained as 74 μm, 128 μm, and 215 μm. An experimental investigation of the functional behavior such as corrosion, microhardness, and erosion of the coated steel at different operating temperatures was undertaken to determine the suitability of its application in the industry. Erosion tests were conducted in an air jet tribo-tester utilizing alumina as an erodent with normal impingement angle at room temperature, 300∘C, and 600∘C. It was difficult to identify a single coating thickness that can be satisfactorily used for superior erosive wear properties with corrosion resistance. So modern management tools such as tri-vector and technology sieve analysis procedures as identification techniques were adopted for the selection of the best coating thickness by complying with the mechanical, erosion, and corrosion resistance properties. Steel coated with 128-μm coating thickness provides the best result for a combination of functional characteristics. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the synthesis of polyaniline (PANI) through electrochemical cyclic voltammetry at varying pH levels and its subsequent adsorption behavior towards Congo red. The products were analyzed using Fourier Transform-infrared spectroscopy (FTIR) and Scanning Electron Microscope (SEM). Results showed that acidic conditions led to faster synthesis rates and complete planes with intercalated flakes, while neutral and alkaline conditions resulted in mostly granular aggregates. PANI synthesized with the maximum adsorption capacity is 58.07mg/g. The interaction between PANI and Congo red occurred through protonation-induced positive charges and electrostatic attraction, as indicated by UV–Vis spectroscopy results. The adsorption process followed the Langmuir model and pseudo-second-order kinetic process, indicating a chemical adsorption process. This study emphasizes the significance of pH conditions in polyaniline synthesis and its potential application in dye removal processes. [ABSTRACT FROM AUTHOR]

The wrought nickel–chromium–cobalt Nimonic 90 alloy is widely used in turbine blades, piston rings and forged tools due to their high stress-rupture strength and creep resistance up to 920∘C. The application components showed unavoidable wear behaviors at high loads due to the reduced resistance of the components. Hence, in order to increase the wear resistance of this alloy, Inconel 625 and Nimonic 90 particle depositions have been carried out on Nimonic 90 substrate through the laser-cladding techniques to study the microstructure, mechanical and tribological behaviors of alloys. The phases, microstructure and microhardness of the claddings were investigated by X-ray diffractometry (XRD), Transmission electron microscopy (TEM), Scanning electron microscope (SEM), Energy-dispersive X-ray spectroscopy (EDS) and hardness test, respectively. Results showed that the mean thickness of the interfacial layer of Inconel 625 and Nimonic 90 was 18.51 ± 4 μ m and 90.68 ± 7 μ m, respectively. The microstructure of the cladding surfaces resulted in dendritic and interdendritic structures. An overall analysis found that the gamma-Ni and hard laves phases were presented in Inconel 625 and Nimonic 90 clad surfaces, respectively. Nimonic 90 clad surface had a high hardness and wear resistance compared with Inconel 625 clad surface and substrate due to the present hard laves phase. Besides, the roughness of the Nimonic 90 clad surface was lower compared with the Inconel 625 clad surface and substrate. [ABSTRACT FROM AUTHOR]

A molten salt-assisted method for the synthesis of Eu 3 + -doped bismuth molybdate (BMO: Eu 3 + ) phosphor was proposed. (BMO: Eu 3 + ) phosphors with different phase structures were obtained by changing the calcination temperature. The applications in LED devices and latent fingerprint recognition of the obtained product were explored. The results of structural characterizations and scanning electron microscope (SEM) photographs analysis prove that the products exhibit different crystal structures and morphologies with the change of calcination temperature. Based on the above findings, the as-prepared products have potential applications in the field of WLED and potential fingerprint recognition. [ABSTRACT FROM AUTHOR]

This paper has presented a novel method for the synthesis of regular and reproductive ZnO nanostructures by microwave heating. Unlike the previous studies, it has focused on ZnO nanostructures grown on the Si wafer used as a cover rather than on the precursor top and the results show that ZnO nanostructures with different shapes depending on the amount of mixture and the position in the Si wafer grow on the regular and reproductive basis. In the center of the Si wafer, short and coarse ZnO nanorods have grown, and on the outer edges, the structure of bundles consisting of ZnO nanorods with much longer lengths and smaller diameters has been synthesized. Morphology of ZnO nanorods was characterized by using scanning electron microscope and the nanorods grown on the outer edges had a mean diameter of 200 nm and were up to 1 0 0 μ m long. In order to elucidate the growth mechanism of nanorods, we have carried out SEM, energy dispersive spectrometer (EDS) and XRD characterization, which shows that ZnO nanorods have grown according to VLS mechanism. A controllable growth method of ZnO nanoneedle is suggested. Zinc Oxide powder and graphite mixed in suitable proportions were placed in an alumina crucible, covered with silicon wafer and subjected to microwave heating. ZnO nanostructures such as nanorod bundles were synthesized on the different positions of the silicon wafer and on the sample surface. [ABSTRACT FROM AUTHOR]

In this study, La2Zr2O7, Yb2O3 and Gd2O3-doped La 1. 4 (Gd, Yb) 0. 6 Zr2O7 thermal barrier coatings have been manufactured from the crystalline and amorphous feedstock by plasma spraying. The thickness of the bond coat is 100±25 μ m and the thickness of the top coat is 250±25 μ m. Thermal shock tests were carried out in furnace temperature of 1200∘C. The thermal shock tests indicate that lifetime of the La 1. 4 Gd 0. 6 Zr2O7 coating has 55 cycles which is the highest thermal shock lifetime compared to other coatings in this study. The type of feedstock, amorphous or crystalline, strongly affects the thermal shock lifetime of La2Zr2O7 coatings. Coating damage after thermal shock tests was investigated using scanning electron microscope to observe the microstructure and X-ray diffraction techniques to analyze the phase composition. The failure of coatings is mainly in consequence of the accumulation of stress between bond coat–ceramic coat interface due to thermal expansion coefficient differences and thermally grown oxide layer formation during thermal shock cycling tests. [ABSTRACT FROM AUTHOR]

In this work, the Metal Inert Gas (MIG) welding process is used for depositing the Inconel 718 over the base substrate of Stainless steel 321. The optimal welding conditions like 50% overlap, Direct Current (DC) plus mode with a pulse on time (1–5 s), frequency (0.25–1 Hz), peak current (120 A), base currents (60% of peak current), and speed (150–350 mm/min) are used for the successful hard-facing. The quality of the hard-facing is analyzed by conducting microstructural studies, tensile tests, microhardness, wear behavior, and electrochemical studies. Post-processing for wear and electrochemical studies is done by Scanning Electron Microscope SEM–EDX analysis. Microstructural studies revealed the presence of columnar dendrites and equiaxed at the top of the hard-faced layer. Hard-faced layer depicts the highest ultimate tensile strength of 772 N/mm2 with an elongation of 31.50% due to the support of Nickel components. The presence of the voids and dimples is identified from the SEM fractography. The maximum hardness value of 212 HV 0. 5 is measured at the top of the hard face layer. The microhardness of the hard-faced layer increased by 17.77% higher than its base substrate. Because of the hard precipitates and higher microhardness made by the weld thermal cycle, the hard-face layer showed maximum Co-efficient of Friction (CoF) of 0.540. Debris and grooves are found with the SEM examination of the wear specimens. Higher impedance offers better corrosion resistance to the hard-faced layer Inconel 718. The EDX analysis confirms the presence of Chromium, Molybdenum, and Niobium contents at the hard-faced layer. These elements silently support better corrosion resistance compared to the base substrate of Stainless steel 321. [ABSTRACT FROM AUTHOR]

Nanoparticles of zinc selenide (ZnSe) were produced by an innovative, uncomplicated, and extremely rapid process that took no longer than a few seconds. For the production of zinc ions, zinc chloride was utilized, and selenium was used for the production of selenium ions. The effect of Zn to Se ions ratio on optical properties has been examined. The prepared nanoparticles were tested and characterized by using transmission electron microscope TEM, scanning electron microscope SEM and UV–Visible spectroscopy. The morphological results revealed that the ZnSe has a spherical shape with mean diameter around 15 nm and the band gap of the ZnSe increases with increasing the Zn content in the sample. The prepared materials were tested as antibacterial agent. [ABSTRACT FROM AUTHOR]

The catalyst surface was processed in the high-voltage electrical discharge device in oxygen environment. Continuous active oxide centers formed on the surface and complete filling of the surface with oxygen occur, and its thermo-physical properties, thermo-luminescence curves, scanning electron microscope and ESR spectrometers were studied. It was determined that the activity of the catalyst at values of the absorbed dose D ≤ 2 1 kGy is many times higher than that of conventional catalysts. Thus, due to the sorption volume of the surface, the volume of the product formed in the liquid phase increases by 1.6 times. [ABSTRACT FROM AUTHOR]

In recent years, the use of natural fibers has increased in manya applications, particularly in automotive industry, owing to their lightweight, high specific strength, recyclability, and ecological properties. This study aims to investigate the influence of copper filler on fiber-coated hybrid composite through mechanical and machining (CNC milling) characterization. Initially, the copper filler was characterized using the energy dispersive X-ray (EDX), particle size analysis (scanning electron microscope), and component analysis (X-ray diffraction (XRD)). Four coated natural fiber/wire mesh hybrid composite designs were developed and identified as hemp/mesh/ramie composite [HMR (1-4)]. In this work, 16 experiments were designed by central composite design (CCD) using Design Expert 13, considering the spindle speed, feed rate, and composite type as input parameters. The results indicate that copper filler particle proportion influenced the tensile strength and impact resistance of the HMR hybrid composite (16% & 15.42%). A fiber coating with a higher infill percentage reduces water absorption. The responses were estimated based on the resultant force and surface roughness, which were influenced by the weight percentage of the filler. In all the spindle speeds, the resultant forces are increased with raise in feed rates (120–600 mm/min). [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]

The lead-free ceramics (1 − x)(0.94 Bi 0. 4 7 Na 0. 4 7 Ba 0. 0 6 TiO3-0.06BiAlO3)- x AgNbO3 (denoted as BNBTA- x AN) were synthesized via a solid-state sintering method. The effect of AgNbO3 doping amount on dielectric properties of the ceramics was studied systematically. X-ray diffraction (XRD), scanning electron microscope (SEM) and Raman spectroscope were used to detect the structure of the ceramics. Temperature-dependent dielectric spectra, frequency-dependent dielectric constant and alternating current (ac) electric conductance at various temperatures were measured. The doping of AgNbO3 greatly reduces dielectric constant around Curie temperature and thus enhances the temperature stability of the dielectric constant. The ceramic BNBTA-0.03AN exhibits excellent temperature-stable dielectric properties with temperature coefficient of capacitance (TCC) ≤ ± 15% between 55∘C and 418∘C with temperature window 363∘C and small changes of dielectric constant and dielectric loss from 100 Hz to 1 MHz at different temperatures. The obtained ceramics are expected to be used in high-temperature capacitors due to its excellent temperature stability. [ABSTRACT FROM AUTHOR]

In this study, proanthocyanidins-functionalized Fe3O4 magnetic nanocomposites were synthesized by the hydrothermal method. The prepared Fe3O4 nanocomposites were characterized by Fourier transform infrared spectrometer (FTIR), X-ray powder diffractometer (XRD), physical property measurement system (PPMS), particle size analyzer, scanning electron microscope (SEM), and transmission electron microscope (TEM). FTIR results indicated that the obtained products were coated with proanthocyanidins. The SEM and TEM results, as well as particle size distribution analysis, revealed that the obtained products were spherical particles with average diameter of 3 2 8. 6 2 ± 2 6. 7 5 nm. XRD and PPMS characterization confirmed that the Fe3O4 nanoparticles have a cubic spinel structure with magnetic properties. The performance of the Fe3O4 nanocomposites for removing organic dyes in an aqueous solution was investigated. The synthesized products were found to be effective on removing various organic dyes, such as Methylene blue (MB), neutral red (NR) and Rhodamine B (RhB), indicating their considerable potential as efficient dyes adsorbents for wastewater treatment. Proanthocyanidins-functionalized Fe3O4 magnetic nanocomposites were synthesized by the hydrothermal method. The obtained Fe3O4 nanocomposites can efficiently remove the organic dyes in an aqueous solution. Proanthocyanidins-functionalized Fe3O4 magnetic nanocomposites had the potential to be developed as efficient dyes adsorbents for wastewater treatment. [ABSTRACT FROM AUTHOR]

Using the mixed solution of n -butanol and ethanol as solvent, the sodalite nanocrystal aggregate was prepared by the solvothermal method. The influences of crystallization temperature, molar ratio Na/Al, crystallization time and silane concentration on the morphology, crystallite size, degree of crystallization and pore structure of the as-prepared samples were investigated by X-ray diffraction (XRD), BET, FTIR, Transmission Electron Microscopy (TEM) and scanning electron microscope (SEM). The results reveal that the sodalite nanocrystals are aggregated by self-assembly into the micropore–mesopore–macropore structure. Higher crystallization temperature and longer crystallization time are conducive to the growth of sodalite nanocrystals. It is a necessary condition for the formation of sodalite nanocrystals to keep high molar ratio Na/Al. The higher the molar ratio Na/Al, the more favorable the crystallization of sodalite nanocrystals. The appropriate concentration of silane agent is conducive to the preparation of smaller crystal-sized sodalite nanocrystals. After removing the silane agent by pickling, the sodalite nanocrystal aggregate is a multistage porous structure with the pore volume of 1.0133 mL/g and the specific surface area of 449.73 m2/g. The preparation of nanocrystal sodalite by solvothermal method, the introduction of Hexadecyltrimethoxysilane as a surfactant, followed by acid pickling to remove the surfactant, produced multistage porous sodalite nanocrystal aggregate, greatly improving the mass transfer rate of sodalite, making it applicable to a wider range of fields. [ABSTRACT FROM AUTHOR]

In this paper, the effects of different quenching holding times on the microstructure and properties of high-silicon hypereutectic high-chromium cast iron (Fe–4.0C–35.0Cr–1.9Si) were investigated. The effect of quenching holding time on the microstructure of high silicon hypereutectic high chromium cast iron was analyzed by optical microscope, scanning electron microscope and X-ray diffractometer. The hardness and wear resistance of high-silicon hypereutectic high-chromium cast iron quenched at 1150∘C for different time were tested by Rockwell hardness tester, microhardness tester and wear tester. The results show that the microstructure of as-cast high-silicon hypereutectic high-chromium cast iron is mainly composed of pearlite matrix and M7C3 carbide. Quenching heat treatment makes part of the matrix transform from pearlite to martensite, and precipitate a small amount of M 2 3 C6 type secondary carbide. With the increase of quenching holding time from 1 h to 6 h, the amount of martensite transformation gradually increases, the primary carbide has no obvious change, the eutectic carbide tip dissolves, and the morphology gradually becomes smooth. The hardness and wear resistance both increase first and then decrease. After 4 hours of insulation, the hardness reaches the highest 60.5HRC, which is increased by 3 HRC compared to 1 hour of insulation. The wear resistance increases by 22.1% compared to 1 hour of insulation. At this time, the wear resistance is the best. [ABSTRACT FROM AUTHOR]

In this communication, the synthesis (solid-state sintering) and characterization of a double perovskite BiFeMoO6 are reported. Analysis of X-ray diffraction (XRD) data provides monoclinic crystal symmetry with an average crystallite size of 85.6 nm and lattice strain of 0.00078, respectively. The microstructural analysis of the sample was done using a scanning electron microscope (SEM) and the results show that grains are well-grown and distributed uniformly throughout the sample surface. The grains are visible clearly due to well-defined grain boundaries, and the effect on the mechanism of electrical ac conductivity was studied. The compositional purity of the sample was checked by energy dispersive X-ray (EDX) analysis spectrum which supports the presence of all constituent elements (Bi, Fe, Mo and O) in both weight and atomic percentages. The study of the Ultraviolet–Visible spectrum provides a bandgap energy of 1.8 eV, suitable for photovoltaic applications. The measurements of the dielectric were used to confirm the existence of the Maxwell–Wagner type of dispersion. The study of impedance spectroscopy helps to understand the negative temperature coefficient of resistance (NTCR) character while the electrical modulus measurements claimed a non-Debye relaxation mechanism in the sample. The study of ac conductivity reveals the fact of thermally activated conduction mechanism in the sample. The presence of the semiconducting nature of the sample was checked from both Nyquist plots and Cole–Cole plots. The study of the resistance versus temperature reveals the fact of negative temperature coefficient (NTC) thermistor character and is suitable for some temperature sensor devices. [ABSTRACT FROM AUTHOR]

In the current scenario, many researchers aspire to develop biodegradable material for biomedical implant applications. Magnesium (Mg)-based alloys are most promising materials since they have mechanical properties similar to human bone. In this study, Mg alloy AZ31 matrix was reinforced with a seashell powder (2 wt.%) and zirconium dioxide (10 wt.%) using bottom pouring stir casting furnace. Scanning electron microscope (SEM) with energy dispersive spectroscopy (EDS) images confirms the proper distribution of reinforcement throughout the matrix. This study analyzed the influence of WEDM process parameters for the material removal rate (MRR) and surface roughness (SR) of the proposed composite. According to Taguchi's L9 (3 3) orthogonal array the machining was performed to investigate the ideal machining parameters with a range of pulse current (I p) 6–8 amps, pulse-on time ( T on ) 5–15 μ s and pulse-off time ( T off ) 10–30 μ s, respectively. Analysis of variance (ANOVA) result confirms that I p (45.86%) has the most influencing parameter affecting the MRR and SR, followed by T on (25.10%) and T off (17.19%), respectively. Furthermore, Technique for Order Preference by Similar Ideal Solution (TOPSIS) and desirability approach was employed to find the optimal parameter combinations to attain the best combined output responses. [ABSTRACT FROM AUTHOR]

In the present scenario, electrochemical arc machining (ECAM) (hybrid of electric discharge erosion and electrochemical dissolution) is an evolving procedure for difficulty in machining the materials due to constraints of existing processes. This research aims to investigate the machinability of Ni 5 5. 7 Ti alloy through electrochemical arc drilling using molybdenum electrode. Electrolyte concentration (ethanol with ethylene glycol and sodium chloride), supply voltage, and tool rotation are considered as the variable factors to evaluate the ECAM performance characteristics in drilling blind hole operation concerning overcut (OC), tool wear rate (TWR) and materials removal rate (MRR). Consequently, response surface methodology is implemented for predictive modeling of various performance characteristics. Finally, multi-objective optimization through desirability function approach (DFA) has produced a set of optimal parameters to improve the productivity along with the accuracy, which is the prime requirement for the industrial applicability of the ECAM process. Results demonstrated that supply voltage is the influential key factor for improvement of machining rate. Scanning electron microscope (SEM) photographs revealed the development of heat affected zone (HAZ), white layer, melted droplet, craters, re-solidified material, ridge-rich surface and voids as well as cavities around the end-boundary surfaces of a blind hole. Composition analysis through energy dispersive spectroscopy (EDS) indicated the oxygen content on the machined surface because electrolyte breakdown causes oxidation to take place at elevated temperatures across the machining zone. Moreover, carbide precipitation like TiC was found in the melting zone of the drilled hole, as revealed by X-ray diffraction (XRD) analyses, which has the affinity to reduce the SMA properties in HAZ. [ABSTRACT FROM AUTHOR]

There arises the formation of thin films of cobalt monosilicide (CoSi) deposited into the base surface of SiO2/Si (111) using magnetron ion-plasma sputtering and subsequent thermal annealing. It was found that, in addition to the formation of CoSi silicide, also there are Co and Si atoms that do not form bonds on the surface. Therefore, in this work, we studied the surface morphology and composition of a CoSi silicon target using a scanning electron microscope. The study, silicide CoSi, was chosen as the target and standard SiO2/Si (111) was used as the substrate. The surface morphology and composition of the CoSi silicon film obtained by scanning electron microscopy had been studied. The paper reports on a method, morphology of the surface of a CoSi silicon film obtained using Raman microscopy. The results obtained are based on the fact that they were obtained using a modern magnetron sputterer, a high-vacuum thermal heater and modern devices. [ABSTRACT FROM AUTHOR]

AlMg0.5Si (AA6063) as a base matrix composite with different weight percentages of Titanium (Ti) has been synthesized by the stir casting method. Objective of this research is to investigate the effect of Ti addition on AA6063 to produce aluminium matrix composites (AMCs). AA6063, AA6063/4%-Ti, AA6063/8%-Ti, and AA6063/12%-Ti are different volume fractions. The Scanning electron microscope (SEM) analysis is used to examine the modified grain refinement and worn surface on fabricated AMCs. The evenly distributed structure was attained on the processed AA6063/Ti combinations. The mechanical properties of processed composites were investigated with the following experimental tests such as tensile strength, impact strength, micro hardness, compressive, and flexural strength. The entire mechanical properties of fabricated AMCs were enhanced with increasing Ti reinforcement particles. The CNC drilling of AA6063/Ti composites was machined by spindle speed, feed and depth of cut. The gray relational analysis (GRA) was used to carry out the optimal machining parameters with their responses such as material removal rate and surface roughness. From the analysis of ANOVA, spindle speed parameter achieved most influencing parameters. [ABSTRACT FROM AUTHOR]

In this study, we aimed to modify polymeric membranes by incorporating magnetic nanoparticles (NPs) to enhance their properties. The structural and chemical properties of magnetic NPs of iron oxide were prepared via a wet chemical method. Iron oxide nanoparticles (IONPs) were used as the core and were coated with polymers polyvinyle alcohol (PVA) and polyvinylpyrrolidone (PVP). The prepared samples were cast on a glass substrate using a casting knife. The aim of this study is the use of a specific type of magnetic NPs, coated with a polymer, and their application in membrane modification. We employed a facile synthesis method to coat the IONPs with the polymer and characterized the resulting material using various techniques, including X-ray Diffraction (XRD), scanning electron microscope (SEM), Fourier Transform Infrared (FTIR) Spectroscopy, and UV/Visible (UV–Vis) Spectroscopy for structural, morphological, chemical bonding, and optical properties studies. Our results show that the modified polymeric membranes exhibited improved properties, such as increased permeability and selectivity. We also observed that the magnetic NPs helped in the easy recovery of the modified membranes using an external magnetic field. Some agglomeration of IONPs was also observed, and the polymer membrane caused a decrease in crystallinity of IONPs. Overall, this study presents a promising approach for enhancing the properties of polymeric membranes using magnetic NPs and can potentially have practical applications in various fields, such as water treatment, food processing, and biotechnology. [ABSTRACT FROM AUTHOR]

A novel cupric oxide nanoparticles (CuO NPs) infused graphite electrode (CuO@GP) was synthesized for simultaneous detection of epicatechin (EC) and theophylline (TH) in black tea. The CuO NPs were synthesized via the sol–gel method and characterized using X-ray diffraction and a scanning electron microscope. The electrochemical sensor performance was studied using cyclic voltammetry and differential pulse voltammetry revealing the presence of TH and EC simultaneously in black tea. The electrode demonstrated a linear range of 50.0–100.0 μ M for both analytes, with a room temperature limit of detection (4.0 μ M for EC, 27.0 μ M for TH). Under the optimal conditions, it showed repeatability (with a relative standard deviation (RSD): 1.61% EC, 0.96% TH), reproducibility (RSD: 1.07% EC, 1.14% TH) and stability (RSD: 2.16% EC, 2.15% TH). CuO@GP exhibited notable selectivity and promising results in tea samples, achieving recovery rates of 102–107% for EC and 101.7–106% for TH. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) occupy a major part in biomedicine due to their unique physicochemical and biological properties including anti-microbial and anti-cancer activity. Evolvulus alsinoides (EA), commonly known as "Dwarf morning glory", is a flowering plant with unique medicinal properties. This plant is reported for its therapeutic significance in chronic bronchitis, asthma and even possesses higher pharmacological properties. In this study, we have reported the synthesis and biological properties of quercetin functionalized biogenic silver nanoparticles (Qur-EA-AgNPs). AgNPs were synthesized using EA Leaf extract and functionalized with Quercetin. Qur-EA-AgNPs were characterized using various techniques and their biocompatibility was investigated. The UV-Visible spectrum of EA-AgNPs revealed a maximum absorbance at 428 nm and quercetin functionalization results in a shift towards 390 nm. The intense peak in the Fourier-transform infrared spectroscopy (FTIR) spectra revealed the quercetin functionalization on EA-AgNPs. Scanning electron microscope (SEM) results confirmed the spherical morphology of quercetin-functionalized AgNPs with a size range around 20 nm which was further confirmed by High resolution transmission electron microscope (HRTEM). Energy Dispersive X-ray (EDX) spectrum evidenced the presence of Ag, C and O. Hemocompatibility of Qur-EA-AgNPs was confirmed from hemolytic assay showing < 5% hemolysis. Moreover, Annexin V PI assay on Qur-EA-AgNPs treated peripheral blood mononuclear cells (PBMCs) showed 78.58 % viability significantly which is comparable with the control cells and its biocompatible nature was proved. In the current study, quercetin-functionalized biogenic silver nanoparticles using E. alsinoides leaf extract have been fabricated and characterized using various techniques. TEM micrograph of functionalized nanoparticles revealed spherical-shaped particles. EDX analysis showed a major elemental composition of silver, carbon and oxygen. The particles are biocompatible towards PBMCs and the erythrocytes. [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]

This research aims to prepare a nanocolloidal solution of gold and gold capped with PVA by chemical reduction method by sodium tri-citrate as a reducing agent and using gold chloride as a source of gold ions in aqueous solution at room temperature (RT). The prepared materials were diagnosed by scanning electron microscope (SEM) with the elemental composition analysis by energy dispersive X-ray (EDX), as well as the X-ray diffraction (XRD). The obtained results showed that the shape of the prepared particles is spherical with enhanced diameters close to 10 nanometers and with good scattering. [ABSTRACT FROM AUTHOR]

In this research, the minimum amount of bio-degradable coconut oil mixed with pressurized air (oil-mist) was first used as dielectric fluid in near-dry WEDM to promote eco-friendly cutting processes. The kerf width (KW), cutting speed (CS), and wire wear ratio (WWR) of coconut oil-mist and demineralized water-mist near-dry WEDM of Monel-K500 alloy have been compared by Taguchi L27 orthogonal array. Experiments were conducted using operating parameters such as air pressure, the flow rate of mixing coconut oil, spark current, pulse duration, and pulse interval. The surface topography of the KW and wire tool surfaces of both near-dry processes are also compared using the scanning electron microscope (SEM) tests. The KW and WWR of the coconut oil-mist process are 6.82% and 15.49% lower, and CS is 21.71% higher than the water-mist process. The contribution of each parameter to responses was also comparatively analyzed. The overall cutting characteristics of coconut oil-mist near-dry WEDM are better than the water-mist process. [ABSTRACT FROM AUTHOR]

In this study, the co-precipitation approach was used to make nanostructured nickel oxide (NiO) commencing with sodium hydroxide (NaOH) and nickel (II) chloride hexahydrate (NiCl2 ⋅ 6H2O). Through the use of X-ray diffraction (XRD), scanning electron microscopes (SEM), UV-visible (UV–Vis) absorption, and Fourier transform infrared (FTIR) imaging, structural and optical studies were investigated. FTIR, photoluminescence (PL), cyclic voltammetry (CV) studies are taken. The synthesized nanoparticles were annealed at 3 0 0 ∘ C and 4 0 0 ∘ C. The face-centered cubic (FCC) structure of the NiO and highly crystallized nanoparticles were revealed by XRD investigations. Observation of FTIR spectra validated the composition of functional groups. Scanning electron microscopy image shows the average size is 24 nm. NiO optical band gap at 3 0 0 ∘ C (3.37 eV) and 4 0 0 ∘ C (2.7 eV) is revealed from UV studies. From CV graph, the sample annealing at 3 0 0 ∘ C and 4 0 0 ∘ C the specific capacitance was 543.6 and 519.8 F/g, respectively. This study signifies the supercapacitor application of nanosized metal oxide. [ABSTRACT FROM AUTHOR]

New chalcogenide semiconductors Cu2NiSSe, Cu2NiSeTe and Cu2NiTe2 with functional properties with partial substitutions Cu → Ni, S → Se → Te are synthesized. An analysis of the morphology and microcomposition of these compositions was carried out. The studies were carried out on a scanning electron microscope (SEM). During the analysis, it was found that the compositions were obtained in the form of polycrystals of sufficiently high purity determined by the percentage of elements in the samples. The formation of crystallites was determined depending on the metal and chalcogen atoms in the compositions. It has been established that the crystallites of the samples synthesized under vacuum conditions in these compositions have a size of d ≈ 3 0 0 μ m. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) and Ag-doped ZnO nanoparticles were synthesized using a soft chemical route, and their properties were characterized using various techniques, including X-ray diffraction (XRD), high-resolution scanning electron microscope (HRSEM), energy dispersive X-ray diffraction spectroscopy (EDS), and high-resolution transmission electron microscope (HRTEM). The ZnO ( Ag x Zn 1 − x O (where x = 0. 0 1 , 0.02 and 0.03) exhibited a hexagonal Wurtzite structure, and Ag doping resulted in the formation of nanorods with decreased grain size. The synthesized materials were found to have antimicrobial properties against human pathogenic bacteria and fungi. MTT assays showed that Ag-doped ZnO had higher cytotoxicity against human embryonic kidney cancer cell lines (HEK 293) compared to pure ZnO. The samples also demonstrated active activity towards the catalyst for the selective oxidation of alcohols. Finally, a statistical model was developed for antibacterial studies using ANOVA, which was consistent with the experimental findings. These results demonstrate the potential of Ag-doped ZnO nanoparticles for use in biomedical and catalytic applications. ZnO nanorods with silver incorporated were successfully synthesized using soft chemical methods using different molar concentrations of silver. The biological and catalytic properties of the synthesized materials can be effectively improved by doping Ag into ZnO. An attempt was made to develop a statistical model and the proposed model is well in agreement with the experimental results. [ABSTRACT FROM AUTHOR]

In this work, A356 alloy samples having a dimension of 4 × 2 0 × 2 0 mm were coated by hard anodic oxidation method at eight different thicknesses up to ∼ 80 μ m. The sample surfaces and longitudinal section of these surfaces in both coated and uncoated conditions were investigated with a scanning electron microscope (SEM). Microhardness of the coating layers and core regions (base metal) were determined with the microvickers hardness testing method. Corrosion properties of the coated and uncoated samples were investigated by an electrochemical corrosion test set up according to ASTM G5 standard. The test results obtained from the coated and uncoated surfaces were compared to each other. Coated surfaces exhibited fluctuant surface profile. Microcracks were formed on these surfaces. Microhardness of the coating layers increased with increasing coating layer thickness. Energy dispersed X-ray spectroscopy (EDS) analysis of the surfaces showed that oxygen rate on the surfaces increased after the corrosion tests. Corrosion rate of the A356 alloy coated by hard anodic oxidation decreased with increasing coating thickness up to 40–50 μ m, but after this coating thickness, the corrosion rate increased. The results obtained from the investigations were discussed based on the characteristics of the coated surfaces. [ABSTRACT FROM AUTHOR]

Hypereutectic Al-Si alloys are widely utilized in the automotive industry due to their high strength-to-weight ratio, minimal thermal expansion, and superior castability. The downside of hypereutectic Al-Si alloys is the formation of coarse primary silicon particles. The primary Si phases were controlled by the growth-hindering agents, phosphorus (refiner), and strontium (modifier) by using a conventional stir casting technique at room temperature. The microstructural changes were observed through an optical microscope and SEM analysis. The additions of 0.08% P have ensured the formation of the uniformly distributed fine-grained particles in the alloy. The primary silicon particle size was reduced from 220 μ m to 150 μ m as compared to the untreated alloy. The tensile and yield properties of the treated alloy were increased by 12.7% when compared to the untreated alloy with a hardness of 131 BHN. The treated alloy imparted better impact toughness, ensuring a ductile mode of failure through the fractography studies. The influence of the microstructure on the machinability of the alloy was investigated in a dry environment with uncoated and coated inserts (code: CCGT 09T304 FL K10) by varying the process parameters, i.e. speed, feed rate, and depth of cut (DoC). Modification of the primary and eutectic Si phases of an Al-20Si hypereutectic alloy increases machinability with coated inserts as well as its mechanical properties. [ABSTRACT FROM AUTHOR]

In this paper, three kinds of Ni–20Cr coatings were deposited on SA516 substrate steel by cold-sprayed coating technique. Physical properties (such as hardness, surface roughness, and residual stress) and slurry erosion behavior (with impingement angles of 30∘ and 90∘) of cold-sprayed substrates have been evaluated. Moreover, a scanning electron microscope (SEM) examination has been performed to evaluate the morphological characterization of various coatings. It has been found that the residual stresses induced in the coated specimens exhibited compressive nature. Further, micro-hardness and surface roughness was observed to proliferate with the incorporation of titanium carbide (TiC) and rhenium (Re) in Ni–Cr coatings. Micro-hardness for Ni–20Cr+TiC and Ni–20Cr+TiC+Re was observed at 233.67 and 278.9 Hv, respectively, where Surface roughness for Ni–20Cr+TiC and Ni–20Cr+TiC+Re was observed at 9.86 and 11.68 μ m, respectively. All types of Ni–20Cr coatings were quite efficient in reducing the erosion rate of the SA516 steel as compared to uncoated SA516 and most prominent of all was Ni–20Cr+Tic+Re coating. It was observed that at 30∘, weight loss for Ni–20Cr, Ni–20Cr+TiC and Ni–20Cr+TiC+Re was up to 0.00027, 0.00015 and 0.00012 g/mm2, whereas at 90∘, weight loss was for Ni–20Cr, Ni–20Cr+TiC and Ni–20Cr+TiC+Re was up to 0.00024, 0.00014 and 0.00012 g/mm2. [ABSTRACT FROM AUTHOR]

The Ni 1 − x CoxTiO3 (0 ≤ x ≤ 1) solid solution powders were prepared by an aqueous sol–gel method. The structural, optical, magnetic and ferroelectric properties of NiTiO3 were investigated by X-ray diffraction, scanning electron microscope, UV–Vis absorption, vibration samples magnetometer and ferroelectric test system. The X-ray diffraction analysis revealed that prepared materials were in a single phase with rhombohedral structure with x up to 1. The increasing Co content resulted in decreasing of tolerance factor and increasing of the lattice constant. The crystalline size increased with an increase of Co content. The optical bandgap value of solid solution increased from 2.23 eV for NiTiO3 to 2.36 eV for CoTiO3. The magnetic hysteresis loop results indicate that all samples showed paramagnetic state at room temperature. A correlation between magnetization values and composition of the materials was observed with magnetization values which increased with increasing of CoTiO3 content in solid solution. Ferroelectric polarization analysis showed that the polarization of the Ni 1 − x CoxTiO3 solid solution depended on x value and reached the maximum with x = 0. 4. [ABSTRACT FROM AUTHOR]

To create a (POT–CSA/ZnO) nanocomposite, a chemical oxidative polymerization of O-toluidine was carried out in the presence of nano ZnO. This step took place throughout the synthesis. In the attendance of hydro chloric acid (HCl) and ammonium persulfate (APS) as an oxidant and camphor solfunic acid (CSA) as a dopant, polymerization can be accomplished by using a monomer mixture with an equal molar ratio. Scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR), and UV–Vis spectroscopy were utilized in the procedure of characterizing the material. The results displayed that the polymer film revealed both excitonic transition π – π and to π − π * transition. The semiconducting character of the composite can be confirmed by its electrical conductivity. [ABSTRACT FROM AUTHOR]

In this work, the experimental investigation of the surface integrity and biomechanical properties of the superficial layer obtained by wire electrical discharge machining (W-EDM) of Ti-6Al-4V alloy for biomedical application has been carried out. The surface morphology and elemental composition of the superficial layer have been investigated by field-emission scanning electron microscope (FE-SEM) and energy dispersive X-ray spectroscopy (EDS) techniques. The micro-mechanical behavior in terms of compressive strength and surface hardness was studied using the micro-pillar and nano-indentation technique. The corrosion resistance and in vitro bioactivity have been investigated using electrochemical and immersion test. Morphological analysis showed that surface morphology and superficial layer thickness were affected by peak current, pulse-duration and pulse-interval. The niobium (Nb)-rich layer was developed in superficial layer zone. The low peak current (3–6 A), low pulse-duration (5–10 μ s) and high pulse-interval (> 4 5 μ s) have been recommended for better surface morphology and thin superficial layer (ranging from 4–6 μ m) free from surface defects. The micro-pillar and nano-indentation results showed that the superficial layer comprised of a brittle structure that improved the mechanical properties of the layer and the compressive strength was measured to be 1198 MPa. The corrosion resistance analysis revealed that the Nb-rich layer in the superficial layer improved the corrosion resistance and bioactivity. Excellent apatite growth has been found in the W-EDM-processed zone. The W-EDM can be used for the biomedical industry as a potential surface engineering technique. [ABSTRACT FROM AUTHOR]

This paper proposes a generative model and transfer learning powered system for classification of Scanning Electron Microscope (SEM) images of defective nanofibers (D-NF) and nondefective nanofibers (ND-NF) produced by electrospinning (ES) process. Specifically, a conditional-Generative Adversarial Network (c-GAN) is developed to generate synthetic D-NF/ND-NF SEM images. A transfer learning-oriented strategy is also proposed. First, a Convolutional Neural Network (CNN) is pre-trained on real images. The transfer-learned CNN is trained on synthetic SEM images and validated on real ones, reporting accuracy rate up to 95.31%. The achieved encouraging results endorse the use of the proposed generative model in industrial applications as it could reduce the number of needed laboratory ES experiments that are costly and time consuming. [ABSTRACT FROM AUTHOR]

Aluminum-based composite materials are frequently preferred in many new-generation engineering applications due to their high strength, wear and corrosion resistance, improvement of mechanical properties, machinability, and low density. Mechanical alloying has an important place in the production of composites with high properties in powder metallurgy, which is one of the composite material production methods. In this paper, the deformation of Al 2024 alloy powder, which is frequently used in the industry, is investigated by the three-dimensional ball mill. Three different rotation speeds (150, 200 and 250 rev/min), three different ball-to-powder ratio (5:1, 10:1 and 20:1) and three different milling times (30, 60 and 90 min) were used in the milling processes. Deformations in the powders were evaluated by particle size analysis and powder structure examination. The obtained results were analyzed with analysis of variance and regression method, three-dimensional graphics, and scanning electron microscope images. When the results are examined, the maximum percent areas covered by the deformed particles and maximum particle size among the selected experimental parameters were obtained at 250 rev/min, 20:1 ball-to-powder ratio and 60 min as 6.849% and 54 μ m. [ABSTRACT FROM AUTHOR]

We synthesized lead-free (1 − x) CaZrO3– x SrTiO3 solid-solution ceramics and studied their structure, dielectric and energy storage properties. X-ray diffraction and scanning electron microscope reveal the microstructure of the samples. A high temperature dielectric relaxation behavior at the temperature ranges of 200 ∘ C–550 ∘ C is found for x = 0. 3 , 0.5 and 0.7 samples. We explore that the origin of high temperature dielectric relaxation behavior is related to the migration of oxygen vacancies by Arrhenius law and oxygen treatment experiment. Moreover, with the increase of SrTiO3 content, the 0.3CaZrO3–0.7SrTiO3 exhibits high dielectric constant ( = 3 6 4 5 at 1 kHz), low dielectric loss (tan δ = 0. 0 0 0 8 1 at 1 kHz), good energy density ( W rec = 1. 2 9 J/cm 3) and high efficiency (η = 8 7. 7 %) simultaneously, and the possible causes of energy storage behavior dependence are analyzed in detail. [ABSTRACT FROM AUTHOR]

Nanostructure-based resistive switching memory devices are being developed for low power, multilevel storage capability, extended retention capacity, and scalable devices. The zinc tungstate (ZnWO 4) nanoparticle was prepared via the facile hydrothermal method. The X-ray diffraction technique confirmed ZnWO4 monoclinic phase and crystallite nature. The scanning electron microscope was used to identify the rod-like ZnWO4 nanostructure, and further, the lattice orientation was investigated by high-resolution transmission electron microscopy. X-ray photoelectron spectroscopy confirmed the binding states with composition of ZnWO4. Resistive switching memory based on ZnWO4 was produced and resulted in low-operating voltage. Finding new candidates for the emerging resistive memory technology is vital for the development of next-gen non-volatile memory devices and this study explored the feasibility of one of the multi-functional metal tungstate materials, ZnWO4 in the ReRAM memory application. The synthesized nanostructures are characterized to acquire the composition and bonding features which are crucial for the device performance. A non-volatile memory device based on ZnWO4 nanostructures synthesized through hydrothermal method is fabricated and the device performance is studied deliberately. [ABSTRACT FROM AUTHOR]

For rare earth conversion coatings (RECCs) on the surface of magnesium alloy (MA), their electrochemical impedance spectroscopy (EIS) evolution and characteristics during the process of coating degradation in environmental media were involved relatively few. In this work, a cerium-based RECC (Ce-RECC) was prepared on the surface of MA AZ91D with chemical conversion technique; for Ce-RECC, its morphology was characterized with optical microscope (OM) and scanning electron microscope (SEM) observations, its composition was characterized with energy dispersion spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) detections, and its protection was characterized with potentiodynamic polarization and EIS tests. Ce-RECC exhibited a mud-crack morphology and was composed of Ce and O mainly, and the corrosion current density ( i c ) and the coating resistance ( R c ) for Ce-RECC-coated MA AZ91D were smaller and larger than those for bare MA AZ91D, respectively. During the process of Ce-RECC degradation in 3.5% NaCl solution, the EIS of Ce-RECC-coated MA AZ91D always comprised a capacitive loop at high frequency region and an inductive loop at low frequency region, which was independent of time extension; however, the value of R c for Ce-RECC decreased gradually with the extension of time, and the total degradation of Ce-RECC consumed 77 h. [ABSTRACT FROM AUTHOR]