As expected from the alloy design procedure, combined twinning-induced plasticity and transformation-induced plasticity effects are activated in a metastable β Ti–12 wt.% Mo alloy. In situ ...synchrotron X-ray diffraction, electron backscatter diffraction and transmission electron microscopy observations were carried out to investigate the deformation mechanisms and microstructure evolution sequence. In the early deformation stage, primary strain/stress-induced phase transformations (β→ω and β→α″) and primary mechanical twinning ({332}〈113〉 and {112}〈111〉) are activated simultaneously. Secondary martensitic phase transformation and secondary mechanical twinning are then triggered in the twinned β zones. The {332}〈113〉 twinning and the subsequent secondary mechanisms dominate the early-stage deformation process. The evolution of the deformation microstructure results in a high strain-hardening rate (∼2GPa), bringing about high tensile strength (∼1GPa) and large uniform elongation (>0.38).
•XRD, FT-IR, UV–Vis and Raman spectroscopy.•Photoluminescence.•DFT calculations.
A new intercalation crystalline polymer compound of bis m-nitroanilinium tetrachlorocadmate (II) {(m-C6H7N2O2)2CdCl4}n ...was synthesized and analyzed using single crystal SXRD, differential scanning calorimetry (DSC), DFT analysis, thermal gravimetric analysis (TGA) and FT-IR, Raman, UV–Vis, fluorescence spectroscopy techniques. X-ray diffraction analyses (SXRD, PXRD) show a layered structure consisting of alternating organic bilayers and two-dimensional inorganic sheets in which each CdCl6 octahedron shares four corners with adjacent octahedra. The crystal packing is consolidated by means of classic and non-classic hydrogen bonds and π-π interactions. At room temperature photoluminescence spectra of {(m-C6H7N2O2)2CdCl4}n yield broad peaks in the 469–770 nm range with full width at half maximum (FWHM) values up to 153 nm. Besides, this compound exhibits a semiconducting behavior with bright red-light under 360 nm ultraviolet photoexcitation and possesses a large Stokes shift and direct band gap of 2.69 eV which overlaps well with solar spectrum. The CIE chromaticity coordinates of {(m-C6H7N2O2)2CdCl4}n are (x = 0.4704 and y = 0.4523). The color rendering index CRI and the low correlated color temperature CCT are 84 and 2861 K, respectively. Electronic structure (BS, DOS and PDOS), and optical properties (dielectric constant ε(ω), refractive index n(ω), reflectivity R(ω), absorption coefficient α(ω), optical conductivity σ(ω) and energy loss function L(ω) with the incident photon energy) were determined using (DFT) calculations by CASTEP code.
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Rare earth Yttrium doped Co0·85Zn0.15YxFe2-xO4 ferrites were synthesized by the standard double sintering method. The basic structure and phase formation of the samples were studied by the technique ...of XRD, reporting the formation of spinel cubic structure. Structural X-ray density was always greater than the bulk density. The microstructural grain size was obtained by SEM and confirmed that the microstructural grain size decreased at initial doping of Y3+ ion. The VSM shows the saturation magnetization decreases with increasing Y content but we get comparatively large retentivity and coercivity of the doped samples. Frequency dependent permeability measurements show that the initial permeability was stable in a long frequency range up to 108 Hz and the magnetic loss tangent was decreased with increasing Y content. All the structural and magnetic properties make these Co–Zn–Y ferrites more suitable for magnetic recording materials.
•Co0·85Zn0.15YxFe2-xO4 ferrites were synthesized by the standard double sintering method.•XRD shows the phase formation of the samples and confirms that the samples are spinel cubic.•SEM images clearly show the surface morphology of the ferrites.•VSM provides the M−H loop properties of the samples, and confirms that the doped samples have more coercivity than the pure Co–Zn samples.
The effect of two concentrations of H2S (0.5 and 2.5 ppm), in controlled laboratory conditions (20 °C, 75%RH), on the atmospheric corrosion of pure Ag, Cu and Ni was investigated in this study. The ...corrosion product morphology and composition were analysed through a multi-technique approach including SEM/EDX, Raman spectroscopy, XPS and XRD. Different corrosion products were identified depending on the type of characterisations providing a better overview of the effect of H2S on the atmospheric corrosion of pure Ag, Cu and Ni. Possible mechanisms involved in the formation of these corrosion products are also discussed in this work.
•Investigations on the effect of H2S on the atmospheric corrosion of Ag, Cu and Ni.•Characterisation of corrosion products using a multi-analytical investigation approach.•Identification of possible mechanisms involved in the atmospheric corrosion of Ag, Cu and Ni.
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•Series naturally graphitized coals were classified into four categories in this study.•Anthracite and meta-anthracite have amorphous carbon structure.•Multi nano carbon structural ...phases were detected in the series graphitized coals.•Different kerogen types shows different graphitization abilities in natural process.
Low-weight components of coal macromolecule were subjected to pyrolysis and condensation when magmatic rock intruded into coal measure, eventually, the residual condensed aromatic components can transform into microcrystalline graphite (coaly graphite). To study the structural transformation from anthracite to natural coaly graphite, ten samples with different graphitization degrees from Xinhua and Lutang of Hunan Province, China were characterized by organic geochemical analysis, X-ray diffraction (XRD), Raman spectroscopy, and high-resolution transmission electron microscopy (HRTEM).
The geochemical parameters (proximate and ultimate analyses) and structural features (XRD, Raman, and HRTEM) of the series naturally graphitized coals exhibit a progressive change as the samples' locations closing to the intrusion. The series naturally graphitized coal samples were classified into four categories, including anthracite, meta-anthracite, semi-graphite, and coaly graphite. But, single parameter cannot classify the series metamorphosed coals well, multi parameters including ash free-basis volatile matter, petrographic features, and carbon structural parameters (based on XRD and Raman spectroscopy) should be considered, additionally, the lattice fringe change observed under HRTEM from anthracite to coaly graphite can verify for the classification. The relatively lower metamorphic grade samples (anthracite and meta-anthracite) have small crystalline sizes, prominent disorders, and amorphous carbon structure, whereas the crystallite structure of highest grade samples (coaly graphite) is three-dimensional crystalline order (testified by XRD and HRTEM), indicating a totally structural transformation from amorphous carbon of anthracite to highly ordered crystalline carbon of coaly graphite in the course of natural graphitization. The carbon structural evolution of coal under natural graphitization process will probably be helpful for synthetic graphite using coal to replace the expensive petroleum coke in the future.
The microstructure and morphology of 70% TiO2–30% Al, 70% TiO2–30% Al2O3, 55% TiO2–045% Al and 55% TiO2–45% Al2O3 composite powders were prepared by Smart Mini Ball Miller. They are characterized by ...XRD, SEM, EDAX, FTIR and TG/DSC. The XRD results showed that composite powders were mainly in the amorphous anatase phase with high crystallinity. The SEM study of composite powders reveals the average particle size is 100±20 nm. In FTIR, peaks observed at around 460 cm−1–560 cm−1 represent bending vibrations of Ti–O–Ti groups in the composite powders. In TG/DSC analysis, there is weight gain in TiO2–Al composite powders where as weight loss in TiO2–Al2O3 composite powders. Finally, microstructure and characterizations of the composite powders during ball milling were investigated to propose an optimal route for obtaining composite powders suitable for thermal spray process.
•Ball milling technique was used for synthesis of TiO2–Al composite powders for thermal plasma coating applications.•The endothermic phase transformation at around 936 °C is developed from orthorhombic to rhombohedral space group.•The particle morphology and size were analysed by SEM and it reveals the average particle size of 100±20 nm.
Recently, there has been a greater emphasis on researching the potential use of ferrite nanoparticles as humidity-sensing materials. We report on the humidity-sensing properties of Mg1-yLiyFe2O4 ...(y = 0, 0.01, 0.03 and 0.05), which were synthesized using the solution combustion synthesis route. According to the XRD analysis, it was observed that both the unit cell volume and the crystallite size increased as the concentration of lithium-ion increased. The crystallite size was measured to be 17–22 nm, indicating the presence of nanomaterials. Moreover, the material exhibited a single phase with the Fd-3m space group, suggesting its structural integrity and uniformity. The FE-SEM images revealed that the porous nature of the material became more pronounced with higher concentrations of Li, indicating potential benefits for sensing applications. The synthesized powder demonstrated promising characteristics for use in humidity sensors. Specifically, it was noted that increasing the Li composition led to a notable increase in resistance, particularly significant for the Li = 0.05 concentration, which exhibited the highest average sensitivity. This suggests that Li doping at this concentration effectively enhances resistance, a crucial aspect for sensor functionality. The response and recovery times of thin film humidity sensors fabricated from these materials were determined to be 9 and 12 s, respectively. These times indicate rapid and efficient sensing capabilities, essential for real-time monitoring applications. Moreover, the newly discovered sensing material exhibited exceptional stability and reproducibility, further highlighting its potential for practical sensor applications. In summary, the synthesized materials show great promise for humidity sensor applications due to their enhanced sensitivity, rapid response and recovery times, as well as their stability and reproducibility. These findings open up avenues for the development of advanced sensing technologies with improved performance and reliability.
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•The low temperature synthesized MnO2 nanostructured electrode material for supercapacitor application has been demonstrated.•As-fabricated electrode showed high specific capacitance ...of ~ 348.2 Fg−1 at a current density of 0.1 mAcm−2.•The fabricated MnO2 supercapacitor electrode demonstrated cyclic stability of 89% after 2000 cycles.
Herein, we are reporting a facile and novel TEA-ethoxylate assisted low temperature hydrothermal route for synthesis of stable nanostructured MnO2 and their application as an electrode material in supercapacitor. The synthesis was accomplished at two different reaction temperatures viz. 60 °C and 80 °C. The synthesized samples were characterized by various physicochemical characterization techniques viz. XRD, FESEM, FTIR and BET-BJH surface area analysis etc. The morphological study of the as-synthesized MnO2 samples revealed the mixed morphology consisting of nanorod and nanocrystals. The electrochemical studies revealed that the sample prepared at 80 °C exhibits superior electrochemical behavior in 1 mol L−1 Na2SO4 liquid electrolyte solution and demonstrated high specific capacitance of ~348.2 Fg−1 at a current density of 0.1 mAcm−2 and energy density of 43.3 WhKg−1. Further, this electrode showed high rate capability of 89% after 2000 cycles. The electrochemical impedance spectroscopic investigations revealed the low equivalent series resistance for MnO2 electrode. This work represents the promising performance of the nanostructured MnO2 electrode for high energy density supercapacitor application.
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