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The residual stresses generated during the solution treatment of large cylindrical aluminum alloy components can impact the dimensional accuracy of structural components and even lead to premature failure of the parts. To reduce the residual stresses generated during the solid solution treatment of aluminum alloys, a new method combining cryogenic control system treatment and oil bath aging was designed. The residual stresses of the specimens were measured using x-ray diffraction and blind hole methods. Changes in the microstructure were observed through scanning electron microscopy and transmission electron microscopy, which revealed the relationship between the dislocation density and the residual stresses of aluminum alloys. The results indicate that this novel treatment method reduced residual stresses by 86%. The reduction in dislocation density and the dispersion of delicate secondary phases through precipitation are the primary intrinsic factors attributed to the reduction of residual stresses in the aluminum alloy through this new treatment method. The finely dispersed second phase helps improve the hardness of the aluminum alloy. [ABSTRACT FROM AUTHOR]

It is greatly significant to achieve a highly selective hydrogen sulfide gas sensor at low temperatures. To improve the gas sensing performance of magnesium ferrite, a nanocomposite of MgFe2O4/MoO3 was prepared through co-precipitation, hydrothermal, and solid-state mixing methods. Crystalline structure, morphology, and elemental composition were analyzed by XRD, FESEM, and XPS. The gas sensing analysis revealed that the n-n heterostructure nanocomposite of MgFO/MoO3 exhibits a 2.10 times greater response than pristine MgFe2O4 towards H2S at 135 °C. The nanocomposite MgFO/MoO3 exhibited a response of 51.36% for 7.2 ppm of H2S at 135 °C. The significant improvement in sensing behavior is attributed to the synergistic effect of n-n nanocomposite. [ABSTRACT FROM AUTHOR]

Abstract The creation of new alloys with improved qualities has become essential in modern industries for high-performance materials. This work’s main objective is to use vacuum arc melting (VAM) to synthesize two different high-entropy alloys (HEAs): AlCrFeNiCu and AlCrFeNiCo. The mechanical properties, phase composition, grain boundaries, and alloy composition of the HEAs were studied. The predominant crystal structure, the Body-Centred Cubic (BCC) phase was obtained for both alloys. Significantly, the Co-containing HEA showed a smaller particle size than the Cu-containing HEA, which led to a 14.21% increase in microhardness. It indicates that the Co-based HEA will likely perform better than the Cu-based HEA in applications prone to abrasion, and indentation, and requiring high hardness levels based on the observed microstructure and hardness parameters. According to wear surface morphology studies, main effects analysis and ANOVA show that increasing loads and sliding distances increase wear rate, whereas sliding velocity has less effect. The best wear rate-reducing parameters are 10 N, 0.5 m/s, and 500 m for Cu-containing HEAs, and the same can be predicted using regression analysis. The study categorizes the intricate worn surface structure by describing different surface properties and wear mechanisms, such as grooves, delamination, adhesive wear, and pitting.

The creation of new alloys with improved qualities has become essential in modern industries for high-performance materials. This work's main objective is to use vacuum arc melting (VAM) to synthesize two different high-entropy alloys (HEAs): AlCrFeNiCu and AlCrFeNiCo. The mechanical properties, phase composition, grain boundaries, and alloy composition of the HEAs were studied. The predominant crystal structure, the Body-Centred Cubic (BCC) phase was obtained for both alloys. Significantly, the Co-containing HEA showed a smaller particle size than the Cu-containing HEA, which led to a 14.21% increase in microhardness. It indicates that the Co-based HEA will likely perform better than the Cu-based HEA in applications prone to abrasion, and indentation, and requiring high hardness levels based on the observed microstructure and hardness parameters. According to wear surface morphology studies, main effects analysis and ANOVA show that increasing loads and sliding distances increase wear rate, whereas sliding velocity has less effect. The best wear rate-reducing parameters are 10 N, 0.5 m/s, and 500 m for Cu-containing HEAs, and the same can be predicted using regression analysis. The study categorizes the intricate worn surface structure by describing different surface properties and wear mechanisms, such as grooves, delamination, adhesive wear, and pitting. [ABSTRACT FROM AUTHOR]

Developing low‐cost and safe batteries with high energy density is promising for large‐scale energy storage applications. Currently, aqueous zinc ion batteries (AZIBs) using Zn metal as the anode have attracted tremendous research attention as the next generation of energy storage devices due to their advantages of high energy density, environmental friendliness, and natural Zn abundance. The utilization of synchrotron X‐ray analytical techniques for in situ/ex situ characterizations offers a comprehensive understanding of the atomic local structure, crystalline structure, chemical states, coordination environment, interface properties, morphologies, and other physicochemical properties of materials on a variety of temporal and length scales, providing valuable insights into the fundamental mechanisms of AZIBs. This review highlights the recent advances and accomplishments of various synchrotron X‐ray techniques, which have been employed to investigate different components of AZIBs and show great promise for battery research and development. [ABSTRACT FROM AUTHOR]

The microstructure at the interface between the cocatalyst and semiconductor plays a vital role in concentrating photo‐induced carriers and reactants. However, observing the atomic arrangement of this interface directly using an electron microscope is challenging due to the coverings of the semiconductor and cocatalyst. To address this, multiple metal‐semiconductor interfaces on three TiO2 crystal facets (M/TiO2─N, where M represents Ag, Au, and Pt, and N represents the 001, 010, and 101 single crystal facets). The identical surface atomic configuration of the TiO2 facets allowed us to investigate the evolution of the microstructure within these constructs using spectroscopies and DFT calculations. For the first time, they observed the transformation of saturated Ti6c─O bonds into unsaturated Ti5c─O and Ti6c─O─Pt bonds on the TiO2─010 facet after loading Pt. This transformation have a direct impact on the selectivity of the resulting products, leading to the generation of CO and CH4 at the Ti6c─O─Pt and Pt sites, respectively. These findings pinpoint the pivotal roles played by the atomic arrangement at the M/TiO2─N interfaces and provide valuable insights for the development of new methodologies using conventional lab‐grade equipment. [ABSTRACT FROM AUTHOR]

Ancient potteries offer valuable information regarding technological advancements, life dynamics, cultural diversity, and trade routes in the past. Earthenware, stoneware, and porcelain from Southeast Asia have been characterized using several analytical techniques, as reviewed in this article. Fluorescent and diffracted X-rays give rise to elemental and phase compositions, respectively. Examination of molecular bonds requires vibrational spectroscopy, which is useful for the identification of organic materials in ancient potteries. With the advent of portable X-ray fluorescence and Raman spectrometry, on-site analysis of archeological ceramics is now possible. For in-depth analysis, synchrotron light sources can provide new insights into artifacts through X-ray and vibrational spectroscopies using elaborate setups. Synchrotron X-ray absorption specifically reveals local atomic structures within artifacts. Charged particles and neutrons are increasingly used as a source of atomic excitation, which improves the depth analysis of artifacts. The obtained elemental composition and mineral phases reveal the origin and production of potteries. Insights into production techniques and firing conditions can be obtained. In addition, the trade routes and networks in ancient Southeast Asia can be established on the basis of archeological ceramic analyses. [ABSTRACT FROM AUTHOR]

Abstract Developing low‐cost and safe batteries with high energy density is promising for large‐scale energy storage applications. Currently, aqueous zinc ion batteries (AZIBs) using Zn metal as the anode have attracted tremendous research attention as the next generation of energy storage devices due to their advantages of high energy density, environmental friendliness, and natural Zn abundance. The utilization of synchrotron X‐ray analytical techniques for in situ/ex situ characterizations offers a comprehensive understanding of the atomic local structure, crystalline structure, chemical states, coordination environment, interface properties, morphologies, and other physicochemical properties of materials on a variety of temporal and length scales, providing valuable insights into the fundamental mechanisms of AZIBs. This review highlights the recent advances and accomplishments of various synchrotron X‐ray techniques, which have been employed to investigate different components of AZIBs and show great promise for battery research and development.

Abstract Hierarchical clustering algorithm has been applied to identify the X‐ray diffraction (XRD) patterns from a high‐throughput characterization of the combinatorial materials chips. As data quality is usually correlated with acquisition time, it is important to study the hierarchical clustering performance as a function of data quality in order to optimize the efficiency of high‐throughput experiments. This work investigated the effects of signal‐to‐noise ratio on the performance of hierarchical clustering using 29 distance metrics for the XRD patterns from Fe−Co−Ni ternary combinatorial materials chip. It is found that the clustering accuracies evaluated by the F1 score only fluctuate slightly with signal‐to‐noise ratio varying from 15.5 to 22.3 (dB) under the experimental condition. This suggests that although it may take 40–50 s to collect a visually high‐quality diffraction pattern, the measurement time could be significantly reduced to as low as 4 s without substantial loss in phase identification accuracy by hierarchical clustering. Among the 29 distance metrics, Pearson χ2 shows the highest mean F1 score of 0.77 and lowest standard deviation of 0.008. It shows that the distance matrixes calculated by Pearson χ2 are mainly controlled by the XRD peak shifting characteristics and visualized by the metric multidimensional data scaling.

Sb-modified alkali bismuth titanate Li0.5Bi0.5−xSbxTiO3 (x = 0 and 0.1) compounds are prepared using the method of solid-state-reaction route. The XRD exploration in environmental conditions confirms the development of new compounds having single-phase orthorhombic crystal structures. Non-uniformly distributed grains are noticed in SEM micrographs for both compounds. The electric & dielectric behavior is analyzed by use of an impedance analyzer. The exploration of the dielectric behaviors of both compounds in a wide frequency range (100 Hz–1 MHz) & temperature range (30–500 °C) suggests that these characteristics are strongly dependent on frequency & temperature. Activation energy assessed from temperature variation of ac-conductivity in various zones recommends that the electric transport phenomenon obeys the Arrhenius equation and shows a mixed type of conductivity. [ABSTRACT FROM AUTHOR]

Sb-modified lithium bismuth titanate Li0.5Bi0.3Sb0.2TiO3 is prepared following the mixed oxide method. The development of a new compound with a single-phase orthorhombic crystal structure is approved from the XRD analysis at environmental temperature. The electrical behavior like dielectric and electrical conductivity are analyzed in a wide temperature as well as frequency range by the impedance analyzer, which exhibits that these properties effectively depend on frequency and temperature. The ac conductivity versus temperatures plots obeys the Arrhenius relation and confirm the presence of the mixed type of conductivity process like space charge conductivity created from oxygen ion vacancies, ionic-polaronic conductivity, and so on, in the sample. Ac conductivity versus frequency spectra is as per Jonscher's Universal Power law. [ABSTRACT FROM AUTHOR]

Structural studies of multilayer magnetic nanostructures formed by alternating layers of transition (Fe) and rare-earth (Gd) metals, which are placed into a hydrogen atmosphere at 100°C, are performed. The hydrogen absorption of rare-earth metals results in the formation of GdHx crystalline phases, the microstructural peculiarities of which are studied by X-ray diagnostics techniques and electron microscopy. [ABSTRACT FROM AUTHOR]

The heterogeneity of polymer electrolyte fuel cell catalyst degradation is studied under varied relative humidity and types of feed gas. Accelerated stress tests (ASTs) are performed on four membrane electrode assemblies (MEAs) under wet and dry conditions in an air or nitrogen environment for 30 000 square voltage cycles. The largest electrochemically active area loss is observed for MEA under wet conditions in a nitrogen gas environment AST due to constant upper potential limit of 0.95 V and significant water content. The mean Pt particle size is larger for the ASTs under wet conditions compared to dry conditions, and the Pt particle size under land is generally larger than under the channel. Observations from ASTs in both conditions and gas environments indicate that water content promotes Pt particle size growth. ASTs under wet conditions and an air environment show the largest difference in Pt particle size growth for inlet versus outlet and channel versus land, which can be attributed to larger water content at outlet and under land compared to inlet and under channel. From X-ray fluorescence experiments Pt particle size increase is a local phenomenon as Pt loading remains relatively uniform across the MEA.

X-ray-based analytics are routinely applied in many fields, including physics, chemistry, materials science, and engineering. The full potential of such techniques in the life sciences and medicine, however, has not yet been fully exploited. We highlight current and upcoming advances in this direction. We describe different X-ray-based methodologies (including those performed at synchrotron light sources and X-ray free-electron lasers) and their potentials for application to investigate the nano-bio interface. The discussion is predominantly guided by asking how such methods could better help to understand and to improve nanoparticle-based drug delivery, though the concepts also apply to nano-bio interactions in general. We discuss current limitations and how they might be overcome, particularly for future use in vivo.

MXene, as a new type of two-dimensional material, has attracted much interest since it was discovered in 2011. However, only few articles discussed the effect of MXene flake size on its electrochemical performance. Here, a sand milling way is explored to produce nano-size MXene and the MILD method is used to prepare micron-size MXene (1 μm) as a comparison. Meanwhile, a mask-assisted interdigital micro-supercapacitors is prepared to explore the dependence of the electrochemical properties of MXene on their flake size. We show that nano-size MXene (200 nm) has a higher ionic conductivity as compared to normal micron-size MXene (1 μm). On the contrary, the larger flake size has higher electrical conductivities. As a result, the capacitance of micron-size MXene is better than nano-size MXene (200 nm) because the electrical conductivities are dominant. This research is helpful for further understanding of the influence of MXene flake size on its electrochemical performance. [ABSTRACT FROM AUTHOR]

Active sites in Mo-based hydrotreating catalysts are produced by sulfidation. To achieve insights that may enable optimization of the catalysts, this process should be studied in situ. Herein we present a comparative XAFS study where the in situ sulfidation of Mo/δ-Al2O3 and Ni/δ-Al2O3 is compared to that of δ-Al2O3 supported NiMo catalysts with different NiMo ratios. The study also covers the comparison of sulfidation of Ni and Mo using different oxide supports as well as the sulfidation conditions applied in the reactor. The XAFS spectra confirms the oxide phase for all catalysts at the beginning of the sulfidation reaction and their conversion to a sulfidized phase is followed with in situ measurements. Furthermore, it is found that the monometallic catalysts are less readily sulfidized than bimetallic ones, indicating the importance of Ni-Mo interactions for catalyst activation. Mo K-edge XAFS spectra did not show any difference related to the support of the catalyst or the pressure applied during the reaction. Ni K-edge XAFS spectra, however, show a more complete sulfidation of the Ni species in the catalyst when SiO2 is used as a support as compared to the Al2O3. Nevertheless, it is believed that stronger interactions with Al2O3 support prevent sintering of the catalyst which leads to its stabilization. The results contribute to a better understanding of how different parameters affect the formation of the active phase of the NiMo catalysts used in the production of biofuel. [ABSTRACT FROM AUTHOR]

Bactericidal effect of copper oxide is still a growing area of research even though a lot of experiments have been carried out by the researchers. The present work was designed to explore structural and optical properties of micro-size copper oxide particles (µCuO) synthesized using microwave irradiation. Synthesized samples were characterized with ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, x-ray diffraction and scanning electron microscopy. Scanning electron micrographs revealed the formation of rod-shaped copper oxide in micron size. X-ray diffraction pattern showed the synthesized microparticles are in monoclinic phase. Solutions of µCuO with various concentrations from 1% to 15% were prepared using dimethyl sulfoxide for the antibacterial study. Starting from 2% concentration, µCuO started to produce a good inhibition zone around the Bacillus subtilis bacteria. The prepared µCuO displayed splendid results in bactericidal activity against Bacillus subtilis bacteria. Higher concentrations of the µCuO showed strong action against bacterial growth. Micro-size copper oxide can also be used as an antibacterial agent like nanosize copper oxide. [ABSTRACT FROM AUTHOR]

Severe plastic deformation through the machining process is an alternative method to achieve better surface features and morphology. In this study, the impact of cutter terminology (Radial Rake Angle) and machining constraints under Minimum Quantity Lubrication condition (constant flow rate) on the XRD spectra and surface features such as hardness, compressive residual stress and wear rate of the slot milled samples has been examined and found that the cutter terminology has offered a greater impact on the surface modification process followed by the machining constraints, owing to the generation of greater strain toughening and thermal soothing effect during the slot milling process. Further, the worn surface morphological analysis has confirmed the enhancement in surface features. [ABSTRACT FROM AUTHOR]

• Analytical results shed light on materials and history of Duszek's Sacred Heart of Jesus. • Superimposed paintings on zinc plate were successfully characterized and interpreted. • IRR, IRFC, MAXRF, and radiography provided thorough stratigraphic information. • Unknown features and vicissitudes of the present artwork were discovered. The research involved the application of multiple non-invasive techniques to investigate an altar painting entitled The Sacred Heart of Jesus by Adolf Herman Duszek using a non-destructive procedure. The painting is an intriguing example of an artwork prepared on a thick zinc support, which is extraordinary and unconventional even in the 20th century. The image is also interesting because it has been damaged and shot through several times during the First and the Second World War. After WWII, the author, A. H. Duszek, performed the restoration of the painting and described this part of its history on the back. So far there has not been a single case in the literature describing the study of the zinc support multilayer painting with the following non-invasive techniques. Here, we discuss the relevance of the applied methods such as infrared reflectography (IRR), false colour infrared reflectography (IRFC), ultraviolet-induced visible fluorescence (UVF), X-ray radiography and macro XRF analysis and their application for an object with this unusual kind of metal support. Finally, an interpretation of the results achieved was compared with the available historical information about the object. [ABSTRACT FROM AUTHOR]

The newfangled Schiff base ligand 2-{[4- (4'- amino- phenoxy)- phenylimino]-methyl}-phenol [HL1], 2-{[4- (4'- amino- phenoxy)- phenylimino]-methyl}- naphthalene-2-ol [HL2], 2-{[4- (4'- amino- phenoxy)- phenylimino]- methyl}- 4 - bromophenol [HL3] and 2-{[4- (4'- amino- phenoxy)- phenylimino]-methyl}-6- methoxyphenol [HL4] and it's In(III) metal complexes had been synthesized. The ligand and metal complexes have been characterized with elemental analysis, UV-visible, IR, 1H NMR spectroscopy, thermal studies, and magnetic susceptibility measurement. The crystallographic investigation reveals the tetragonal geometry of In (III) complexes of Schiff bases HL1 to HL4. Also, the magnetic moment and electronic spectral studies supported the tetrahedral structure In (III) complexes of Schiff bases. The antibacterial and antifungal activity of the Schiff base was accentuated while being coordinated with metal ions. Ligand [HL1-] is immune to both human cancer cell lines, comprehensive of breast (MCF7) and colon (HT29) with GI50 of 62.2 μM, 65.2 μM, 72.2 μM, and 84 μM respectively. In (III) metal complexes confirm adequate activity in the breast (MCF7) cellular cell line with IC50 values of 31.1 μM. [ABSTRACT FROM AUTHOR]

Current work describes eco-friendly synthesis of cobalt ferrite (CoFe2O4) nanoparticles utilizing the flower and leaves extract of Hibiscus rosa-sinensis by chemical co-precipitation method and explored the behavior of CoFe2O4 nanoparticles on humidity sensing for humidity range 15% to 98% at room temperature. The cubic spinel structure of synthesized CoFe2O4 nanoparticles suggests a porous complex shape with an average crystalline size of 23.85 nm. Elemental analysis reveals no signs of impurity. Thermogravimetric analysis and differential thermal analysis showed that the material experienced a transformation toward thermal stability. CoFe2O4 nanoparticles as sensing medium were found to have a practical sensitivity of 40% relative humidity in the atmosphere and a response/recovery time of 5.31/7.75 seconds, respectively. CoFe2O4 nanoparticles are stable over time, according to the findings. CoFe2O4 nanoparticles humidity sensing performance demonstrates their suitability for room temperature-based humidity sensors. A general representation of the synthesis of CoFe2O4 nanoparticles [ABSTRACT FROM AUTHOR]

[Display omitted] • L-glutamic acid effectively inhibits the hydrogen release from aluminum waste. • Addressing the mechanism behind the inhibition effect. • Impact of absence of inhibitor to generate hydrogen was investigated. Aluminum on reaction with water generates hydrogen, aluminum waste (AW) under moist condition causes hydrogen blast. To inhibit the evolution of hydrogen during the reaction of aluminum with water, environmentally friendly L-glutamic acid (GA)was utilized. The results of hydrogen generation experiment show that 0.3 g GA with 0.5 g AW and 0.5 g sodium borohydride (NH) has the ability to suppress the hydrogen generation reaction. The XRD, FTIR and SEM analysis indicate the presence of protective covering film of GA is formed on the surface of AW, blocking the reaction to occur between aluminum with water. This study addresses the lack of research on inhibitors for hydrogen fire blasts when removing wet aluminum dust. [ABSTRACT FROM AUTHOR]

• The porous properties (size distribution) of claystone and cement mortar were analysed by NMR T 2 spectroscopy. • Three-dimensional pore matrix models of claystone and cement mortar were reconstructed based on CT identification techniques. • The pore matrix models reconstructed in 3D based on CT were accurately located and identified in the IIZ. The interfacial influence zone (IIZ) is a weak link between cast-in-situ cement materials and bulk geological materials. Identifying IIZ is essential for studying binary structure's mechanical properties. This paper aims to locate the IIZ of a clay rock-cement mortar (C-C) binary by macro-pore distribution in space using CT and NMR tests. First, the porous properties of clay rock and cement mortar were analyzed by the T 2 spectrum of the NMR test. Mortar's macro-pore volume is larger than clay rock's. Second, the 3D pore-matrix models of these two materials were reconstructed., with larger porosity in mortar than clay rock, consistent with NMR tests. Therefore, the method of pore location using 3D reconstructed models based on CT images may be reliable. Finally, a pore-matrix model of the C-C binary was reconstructed, and the IIZ was identified by pore distribution. The IIZ shape is an approximately ellipsoidal area with thin ends and thick middle, with a max thickness of 8 mm. [ABSTRACT FROM AUTHOR]

Mn-activated ZrO2 nanocrystal was successfully synthesized using the chemical co-precipitation technique. Nanocrystals have been widely studied in terms of their structural and optical aspects. X-ray diffraction (XRD) analysis confirmed the formation of monoclinic and tetragonal phases in pure and Mn-doped ZrO2 nanocrystals. The unit cell structure of m-ZrO2 and t-ZrO2 has been modelled using the Rietveld refinement crystallographic data. A photoluminescence (PL) study revealed emission intensity peaks at 378 nm for pure ZrO2 and 380 nm for Mn-doped ZrO2 nanocrystal under 280 nm excitation. A significant red shift was observed in Mn-doped ZrO2 nanocrystal due to the oxygen vacancy. The incorporation of Mn to ZrO2 nanocrystals reduced the optical band gap from 5.07 to 2.02 eV. The morphological analysis revealed that the typical particle sizes were in the nanoscale range, with 38 nm for pure ZrO2 and 70 nm for Mn-doped ZrO2 nanocrystals. [ABSTRACT FROM AUTHOR]

Cobalt-copper-zinc ferrite (CoCuZnF) nanoparticles were synthesized using the precipitation method. The characterization of CoCuZnF was carried out using powder XRD, Raman, IR, UV–vis, and FEG-SEM. The TG-DSC data of NTO, and nNTO containing the catalyst was used to study the thermal decomposition behavior. Three non-isothermal methods were used to evaluate the kinetic parameters. The kinetics data suggests that incorporation of CoCuZnF additive can effectively decrease the high activation energy of NTO by ∼83–88 kJ mol−1 and nNTO (∼205–216 kJ mol−1). The decomposition of both NTO and nNTO was faster in the presence of CoCuZnF, suggesting its plausible use in the high explosive munitions containing NTO.

[Display omitted] • FeNiCoCrMn HEAs electrocatalysts were electrodeposited on copper foam. • Voltage and additives influence the morphology and HER performance of HEAs catalyst. • Catalyst achieves 10 mA cm−2 at overpotential 191 mV with Tafel slope 84.7 mV dec−1. High-entropy alloys (HEAs) have been paid attention for their exceptional material properties. FeNiCoCrMn HEAs electrocatalysts were synthesized on copper foam by electrodeposition. The effects of deposition potential and additives on the surface morphology and crystal structure of the catalysts were investigated, and their hydrogen evolution reaction (HER) performance in 1.0 M KOH solution was studied. The high deposition potential enhanced nucleation, leading to intricate structural formations, while CTAB and citrate additives notably altered the surface texture of the catalysts, affecting HER activity. Notably, Fe 0.19 Ni 0.24 Co 0.29 Cr 0.18 Mn 0.1 electrocatalyst with a low Tafel slope of 84.7 mV dec−1 showed good HER activity, only required the overpotential of 191 mV to achieve a current density of 10 mA cm−2. [ABSTRACT FROM AUTHOR]

• Composition: MoS 2 /SiC-5/10 wt%, MoS 2 /SiC-7.5/7.5 wt%, and MoS 2 /SiC-10/5 wt%. • Highest fretting wear resistance and hardness were obtained for MoS 2 /SiC-10/5 wt%. • The average coefficient of friction (COF) for MoS 2 /SiC-10/5 wt% was 0.471. • The IMC Al 12 Mo played a crucial role in hardening the composite. In this study, three different types of hybrid composites were developed using AA7075, MoS₂, and SiC through a stir-casting process. The first composite was reinforced with MoS₂/SiC at 5/10 wt%. The second was reinforced with MoS₂/SiC at 7.5/7.5 wt% and the third with MoS₂/SiC at 10/5 wt%. Both reinforcements exhibited hexagonal structures at the casting temperature. The refined grains led to improved mechanical and fretting wear properties. For the composite with MoS₂/SiC at 10/5 wt%, fretting wear resistance was enhanced compared to the other samples. An average coefficient of friction of 0.471 was obtained for the MoS₂/SiC 10/5 wt% sample. XRD results revealed the presence of various phases, including Al 12 Mo. [ABSTRACT FROM AUTHOR]

• Li 7-x Al x La 3 Zr 2 O 12 (x = 0, 0.15, and 0.30) were synthesized. • 15 mol.% Al into LLZO is the optimum for stabilizing cubic LLZO phase. • Tetragonal and cubic LLZO phases can be distinguished by neutron diffraction. • 27Al NMR can be used for the determination of Al3+ incorporation sites in the LLZO. The incorporation of Al in the Li 7 La 3 Zr 2 O 12 (LLZO) structure was systematically investigated using X-ray/neutron powder diffraction and solid-state 27Al nuclear magnetic resonance. Pristine LLZO as well as 15 and 30 mol.% Al-incorporated LLZO materials were prepared by solid-state reaction. The X-ray diffraction patterns confirmed that the incorporation of 15 mol.% Al resulted in the formation of tetragonal LLZO upon calcination at 1000 °C; then, cubic LLZO was obtained after calcination at 1050 °C. In contrast, pristine and 30 mol.% Al-incorporated LLZO only exhibited a tetragonal structure. The detailed structure of 15 mol.% Al-incorporated LLZO was further analyzed by neutron powder diffraction and 27Al nuclear magnetic resonance. These analyses enabled to distinguish the crystal structures of tetragonal and cubic LLZO with similar lattice parameters, and to determine the lattice sites for Al incorporation in LLZO. [ABSTRACT FROM AUTHOR]

• EPMA equipped with WDS and EDS present Sb distribution in the same region. • WDS mapping provides more accurate Sb distribution than EDS. • WDS mapping is recommended for the Sb detection in solders. • WDS with enhanced spectral resolution is dominant to seperate the overlap. This work provides a contrastive analysis of Sb distribution in Sn-57Bi-1Sb solder by WDS mapping, EDS count map and EDS net map. The mapping analysis on the same region shows that the WDS mapping provides the more accurate data on the distribution of Sb compared with EDS analysis, including the concentration gradient of dissolved Sb and the fine SnSb particles with size less than 1 μm. WDS equipped with the enhanced spectral resolution is a critical technique to separate the complex overlap spectrum, which was recommended for the Sb detection in Sb-doped solders. [ABSTRACT FROM AUTHOR]

• Addition of hydrogen made the matrix microstructure finer. • Addition of hydrogen increased the content of β phase. • Distribution of reinforcing phase changed, after melt hydrogenation. • Room temperature fracture toughness (KIC) of TMCs get enhanced. Titanium matrix composites (TMCs) are widely used for their excellent properties. This paper explores fabricating (2.5vol.%TiB + 2.5vol.%TiC)/Ti6Al4V composites under varying hydrogen concentrations in a hydrogen-argon mixed atmosphere, analyzing the microstructure through optical microscopy and scanning electron microscopy with electron backscattered diffraction patterns. The results show that hydrogen leads to microstructure refinement in the matrix, increases β phase content, and modifies reinforcing phase distribution. Three-point bend tests reveal improved room temperature fracture toughness when hydrogen gets incorporated. [ABSTRACT FROM AUTHOR]

• Deformation disparities between grains hinder pseudoelastic recovery. • Multiple martensite variants and slip resolve strain incompatibility in the bicrystal. • High anisotropy of martensite variants difficult the polycrystalline pseudoelasticity. The Fe–Mn–Al–Ni pseudoelastic system has garnered interest for diverse engineering applications owing to its promising characteristics. The poor pseudoelasticity in polycrystals is generally attributed to activation of new martensite variants and the high density of dislocations close to austenite/martensite interface. High-energy synchrotron X-ray diffraction and microscopy studies on a Fe–Mn–Al–Ni bicrystal reveal the sequence of transformation, deformation mechanisms, and grain boundary effects on martensite nucleation, shedding light on its limited pseudoelasticity in polycrystalline configurations. The results highlight challenges in achieving pseudoelasticity in polycrystalline configurations due to disparities in deformation between grains and at grain boundaries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Quantification of CO 2 captured back by lime during carbonation. • Development of carbon capture and utilization unit in construction. • Influence of relative humidity on CCU capacity of lime by carbonation. • Rate of carbonation, crystal morphology and microstructure of carbonation products. • Using lime as building material to achieve sustainable development goals. This study investigated the carbon sequestration potential of air lime by carbonation in two different relative humidity conditions. The carbonation rate and amount of carbon dioxide captured were quantified using weight gain and various analytical techniques. Samples cured in high relative humidity showed almost complete carbon capture by sequestering 94.8 % of carbon dioxide from atmospheric air within 56 days, with calcite crystal formation and a high crystallinity index. Similarly, samples cured in low relative humidity conditions showed slightly less carbonation around 83.8 % with different calcium carbonate polymorphs like aragonite and vaterite, along with amorphous calcium carbonate. Results demonstrated that carbonation of lime is a promising technology for carbon capture and utilization in buildings as non-load bearing mortars or plasters and could be used to reduce carbon dioxide levels in the atmosphere. [ABSTRACT FROM AUTHOR]

Oxygen selective membrane on the base of cermet δ-Bi 2 O 3 /Ag with an interpenetrating structure has the maximum potential efficiency of air separation. However, the degradation processes, including the phase degradation of fluorite δ-Bi 2 O 3 , do not make it possible to create a membrane with the required perfection and durability. In this work, the ordering of oxygen vacancies with the transformation of fluorite into the rhombohedral phase (S.G. R -3) was studied by powder HT XRD in situ at 600 °C on dense Bi 0.78 Er 0.2 Hf 0.02 O 1.51 ceramics. Fast regeneration of disordered fluorite occurs at T = 640–700 °C. The phase degradation of fluorite due to the segregation of dopants at the second stage leads into stable phases - sillenite, tetragonal or rhombohedral phase (S.G. R -3 m), depending on the composition of δ-Bi 2 O 3. Fast regeneration of fluorite occurs when heated to 820 °C, which is unacceptable for membranes. Analysis of all available data allows us to propose approaches to optimize the composition of δ-Bi 2 O 3 and technical solutions for creating durable oxygen selective membranes with promising use in distributed multigeneration. As a result of the analysis, a new solid electrolyte with better parameters was obtained. • Cubic disordered fluorite δ-Bi 2 O 3 with aging at 600 °C degrades in two stages. • Fast heating up to 700°С regenerates fluorite after 1st stage of aging. • Degradation of fluorites on the 2nd stage leads to three stable phases. • Composition of durable fluorite is determined by the choice of operation mode. • The stated limitations were validated and resulted in a better solid electrolyte. [ABSTRACT FROM AUTHOR]

Organic-inorganic hybrid formamidinium lead iodide (FAPbI3) perovskite has shown tremendous attention in recently developed photovoltaics and optelectronic devices. However, it suffers from structural instability complications, particularly the spontaneous phase transition from a dark color photoactive perovskite phase (α-FAPbI3) to a yellow color photo-inactive phase (δ-FAPbI3) at room temperature. To stabilize the photoactive α-FAPbI3, several methods were employed, including compositional engineering, 2D layer deposition on the surface, and solvent engineering method. In this communication, we have proposed a facile sequential rapid annealing method to produce the photoactive α-FAPbI3 perovskite on an industrial scale, which is highly stable at room temperature. The structural, morphological, compositional, and optical properties of the perovskite were studied using X-ray diffraction (XRD), UV–visible absorption, Laser Raman, thermogravimetric analysis (TGA), and field emission electron microscopy with elemental analysis (FE-SEM & EDAX). The strong characteristic diffraction peaks of cubic structure in XRD showed the proposed additives free preparation method is more adaptable for the preparation of high quality α-FAPbI3 perovskite for optoelectronic applications.

The strain profile in the subsurface of He-ion-irradiated W was figured out by unfolding the synchrotron-grazing incidence X-ray diffraction (S-GIXRD) patterns at different incidence angles. The results show that for 2 × 1021 ions/m2 He2+-irradiated W, in addition to a compressive strain exists in the depths of 0–100 nm due to mechanical polishing, an expansion strain appears in the depth beyond 100 nm owing to irradiation-induced lattice swelling. This work provides a reference for the study of irradiation damage in the subsurface by S-GIXRD. [ABSTRACT FROM AUTHOR]

The low‐temperature electronic structure of the van der Waals ferromagnet CrSiTe3 is investigated. This ferromagnetic semiconductor has a magnetic bulk transition temperature of 33 K, which can reach up to 80 K in single‐ and few‐layer flakes. X‐ray absorption spectroscopy (XAS) and X‐ray magnetic circular dichroism (XMCD) measurements, carried out at the Cr L2,3 and Te M5 edges in vacuo‐cleaved single crystals, give strong evidence for hybridization‐mediated superexchange between the Cr atoms. The observed chemical shift in the XAS, as well as the comparison of XMCD with the calculated Cr L2,3 multiplet spectra, confirms a strong covalent bond between the Cr 3d(eg) and Te 5p states. Application of the XMCD sum rules gives a nonvanishing orbital moment, supporting a partial occupation of the eg states, apart from t2g. Also, the presence of a nonzero XMCD signal at the Te M5 edge confirms a Te 5p spin polarization due to mixing with the Cr eg bonding states. The results strongly suggest that superexchange, instead of the previously suggested single‐ion anisotropy, is responsible for the low‐temperature ferromagnetic ordering of 2D materials such as CrSiTe3 and CrGeTe3. This demonstrates the interplay between electron correlation and ferromagnetism in insulating 2D materials. [ABSTRACT FROM AUTHOR]

Raman and photoluminescence spectroscopic studies on oxygen vacancy‐induced structural disorder in Gd2Ti2O7‐δ single crystals grown by optical floating zone technique under argon atmosphere are reported. The oxygen vacancies in Gd2Ti2O7‐δ wafers decrease with thermal annealing in air atmosphere. The full width at half maximum of X‐ray diffraction rocking curve decreases from 245 to 157 arcsec and the optical transmittance increases from 23% to 87% (at 1000 nm) upon post growth thermal annealing. Raman spectroscopic studies reveal a monotonic increase in intensity of O–Gd–O (Eg) and Ti–O (A1g) stretching modes with thermal annealing. Since these modes are associated with modulation of oxygen x parameter which is sensitive to Ti–O octahedron distortion, the increase in Raman intensity indicates an improvement in structural ordering of oxygen sub‐lattice in Gd2Ti2O7‐δ. Moreover, the photoluminescence studies also corroborate the Raman analysis in terms of reduction of structural defects associated with oxygen vacancies as a function of thermal annealing. This study demonstrates the effectiveness of using Raman spectroscopy to probe the structural disorder in Gd2Ti2O7‐δ crystals. [ABSTRACT FROM AUTHOR]

In the present work, ZnO:Dy3+ nanophosphors were synthesized by a simple, cost effective and eco-friendly route using the aqueous extract of Azadirachta Indica leaves. The prepared ZnO:Dy3+ nanophosphors were characterized using X-ray diffraction (XRD), Fourier Transformed Infra-Red (FTIR), Raman, UV-VIS diffuse reflectance (UVDR) spectroscopy and Photoluminescence (PL), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray spectroscopy (EDX). TEM and X-ray diffraction analyses reveal the hexagonal wurtzite structure of the ZnO nanoparticles in the prepared samples. UV-VIS-NIR spectrum of the ZnO:Dy3+ nanophosphor was analysed on the basis of Judd–Ofelt (J-O) theory and the J–O intensity parameters (Ωλ) were calculated. The radiative properties, such as radiative transition probability, branching ratio, stimulated emission cross-section and optical gain were investigated using the J–O intensity parameters. The photo luminescence emission spectra (PLE) of the Dy3+ doped samples exhibits three emission bands relative to 4F9/2→ 6H15/2 (478 nm), 4F9/2→ 6H13/2 (572 nm) and 4F9/2→ 6H11/2 (663 nm) transitions of Dy3+ ions respectively. The CIE chromaticity color coordinate shows that the ZnO:Dy3+ nanophosphors can be useful for white luminescence applications. The result indicates that the prepared phosphors produce white light emission and can be used for near ultraviolet excited white light emitting diode (NUV WLED) applications.

Tricobalt tetraoxide (Co3O4) samples having different thiourea/Co molar ratio of 0, 5 and 10 were prepared by wet chemical synthesis. The effects of thiourea content on the crystal structure-related parameters of Co3O4 were determined. The increase in the amount of thiourea caused a gradual decrease in the lattice parameters and specific surface area and an increase in the crystallinity and crystallite size. The experimental analysis results showed that thiourea content can be used to control the crystal structure-related parameters of Co3O4.

Nanostructured ZnO/CdS composites were synthesized using hydrothermal method by varying the sulphur source; thiourea (TU) and thioglycolic acid (TGA). Pure ZnO and two samples of CdS were prepared by varying the sulphur source in order to compare the results of the nanocomposite with the pure nanomaterials. X-ray diffraction analysis shows the average particle size of the ZnO/CdS (TU) and ZnO/CdS (TGA) nanocomposite to be 12.81 nm and 25 nm, respectively. High resolution TEM analysis shows the particle size of ZnO/CdS (TU) and ZnO/CdS (TGA) to be 12 and 17 nm respectively. UV- visible- reflectance spectra were recorded and the band gaps were estimated to be 2.4 eV and 2.84 eV for ZnO/CdS (TU) and ZnO IR/CdS (TGA). The porosity of ZnO/CdS (TU) was 14 nm and ZnO/CdS (TGA) was 2.5 nm. The photocatalytic activity for the degradation of Mordant black 11 dye under sunlight was studied. [ABSTRACT FROM AUTHOR]

Cr-doped zinc-lanthanum nanoferrites Zn 1- x Cr x La 0.1 Fe 1.9 O 4 (x = 0.09, 0.18, 0.27, and 0.36) were successfully synthesized using sonochemical reactors. Effect of powder production parameters were extensively studied and powder characterization was performed. Existence of cubic spinel structures in the prepared nanoferrites with the average crystallite size ranging from 35 to 51 nm was confirmed by X-ray diffraction studies. An electrochemical impedance analyzer was used to measure the dielectric constant (ε ′), loss tangent (tan δ), and complex dielectric constant (ε ") with respect to frequency and composition ratio. Maxwell–Wagner polarization and hopping mechanism were calculated to distinguish the variations in ε ′, tan δ, and ε ". The Nyquist impedance plots for nanoferrites revealed the pseudocapacitance as well as resistive behavior. Vibrating sample magnetometer studies reveled the ferromagnetic behavior of nanoferrites. Substantially increased saturation magnetization and decreased coercivity were noted with respect to increased Cr2+ ions in the prepared nanoferrites. It was found that the addition of chromium in Zn 1- x Cr x La 0.1 Fe 1.9 O 4 nanoferrites enhances the optical, electrical, and magnetic properties of the nanoferrites. [ABSTRACT FROM AUTHOR]

In this study, the critical effects of variants in machining behavior on the microcrystalline characteristics and its dependence on the corrosion as well as Impedance behavior of the machined Nimonic 263 alloy have been investigated. Because the resulting effect, which arises from the machining process (slot milling) with varying cutter nomenclature or terminology (Radial Rake Angle (RRA)) and machining conditions (cutting feed) under constant Minimum Quantity Lubrication (MQL) flow rate plays a vital role in severe deformation process (SDP) on the machined work surface. Additionally, the Electrochemical Impedance Spectroscopy (EIS) analysis has been conducted over the SDP processed surface to analyze the influence of variants in machining behavior over the corrosion performance through the impedance of machined samples and from the above experimentation, it is stated that the SDP through slot milling has a superior influence on the corrosion and EIS behavior leads to reduction in the resistance against the corrosion tendency of the machined samples related to the nascent Nimonic 263 sample. [ABSTRACT FROM AUTHOR]

This study delves deeply into the effect of different borates (lithium tetraborate, sodium tetraborate, calcium metaborate, ammonium pentaborate) on the production and fundamental characteristic features of nanoscale hexagonal boron nitride (hBN) structure with the assistant of standard characteristic measurement methods, namely, Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), scanning and transmission electron microscopy (SEM and TEM). The hBN samples are synthesized by reaction of powder urea, boron oxide, and different kinds of borates via the modified O'Connor method (performed at a relatively lower main heat treatment temperature of 1,100°C). All the results obtained show that the usage of borates affects positively the formation of nanoscale hBN structure. In more detail, the FTIR experiment results reveal that the presence of two strong c peaks appeared at ~1,380 and ~780 cm−1 in the spectra points out the conventional BN in‐plane and out‐of‐plane vibrations, respectively. The XRD patterns also confirm the production of high‐ordered hBN as the existence of the main peaks of the corresponding hexagonal system. As for the SEM examination, it is found that all the hBN materials exhibit totally different crystallinity quality and microstructural characteristics. The hBN compound prepared by the sodium tetraborate content shows the most uniform surface appearance with the smoothest/densest crystal structure, best grain orientations, and finest grain interactions. Hence, the material with strong stretching of interatomic bonds shows the highest material (fracture) strength. Moreover, the TEM images illustrate that all the products are composed of uniform multi‐walled nanotubes and nanorods with an average length of ~250 nm. [ABSTRACT FROM AUTHOR]

Well-crystalline CeO2-Mg(OH)2 and inverted Mg(OH)2-CeO2 nanocomposites were successfully synthesized by a facile 'one-pot' chemical precipitation method at low temperature. The crystal structure, morphology and optical properties of the CeO2- Mg(OH)2 and inverted Mg(OH)2-CeO2 nanocomposites were investigated using X-ray diffraction, TEM, FTIR, UV-vis absorption and PL spectrometer. The photoluminescence study revealed visible light emission for the nanocomposite. Interestingly, significant red shift observed for Mg(OH)2-CeO2 nanocomposites. The optical tuning nanocomposites can be used for the optoelectronic applications. [ABSTRACT FROM AUTHOR]