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In the current study, iron oxide nanoparticles (IONPs) were synthesized using Ocimum tenuiflorum (OT). The OT leaf extract reduces the ferrous ions to IONPs under microwave irradiation. The biologically synthesized nanoparticles were characterized by Ultraviolet visible (UV–vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and Energy Dispersive X-ray (EDX) analysis. High resolution transmission electron microscopy (HRTEM) analysis shows that the IONPs were 9–21 nm in diameter. The zeta potential value of IONPs (+ 15.8 mV) indicate the moderate stability in aqueous medium. IONPs demonstrated excellent photocatalytic reduction and 72% methylene blue degradation was observed in 90 min. IONPs exhibited significant antimicrobial efficacy towards bacterial pathogens at dose dependent manner. The cytocompatibility of IONPs was studied against normal and tumor cells. Comparing toxicity of the IONPs to the A549 lung cancer cells and RAW 264.7 macrophages, higher toxicity was recorded for cancer cells indicating potent anticancer and higher biocompatibility towards normal cells. [Display omitted] • Biosynthesis of iron oxide nanoparticles (IONPs) using Ocimum tenuiflorum extract. • IONPs demonstrated excellent photocatalytic activity towards methylene blue degradation. • IONPs exhibited dose dependent anticancer activity and high biocompatibility towards normal cells. • IONPs demonstrated dose dependent antibacterial activity towards normal cells. [ABSTRACT FROM AUTHOR]

Background: The emergence of antibiotic resistance and the continuing evolution of resistance even to newer drugs have always been a global challenge. In the pursuit of innovative solutions, there is growing interest in using nanomaterials with antibacterial potentials to combat this menace. Objectives: In this study, plant extract cocktail-mediated silver nanoparticles (PAgNPs) was used to stimulate the antibacterial effect of ampicillin (AMP) against multidrug-resistant (MDR) bacterial pathogens. Methods: The agar well diffusion technique was used to investigate the potentials of PAgNPs in activating the antibacterial activity of AMP in MDR bacteria, including Escherichia coli, Klebsiella pnuemoniae, Micrococcus luteus, and Clostridium difficile. Plant extract cocktail-mediated silver nanoparticles were synthesized by reacting 9 mL of 1 mM of silver nitrate with 0.5 mL each of Citrus limon juice and aqueous Newbouldia laevis extract under bright sunlight for 10 minutes. Plant extract cocktail-mediated silver nanoparticles were characterized using UV-visible spectroscopy (UV-Vis) and higher resolution transmission electron microscopy (HRTEM) with energy dispersive x-ray spectroscopy (EDS). Results: Plant extract cocktail-mediated silver nanoparticles colloidal solution was reddish-brown with a 441-nm surface plasmon resonance (SPR) absorption peak. The HRTEM micrograph showed the varied shaped silver nanoparticles (AgNPs) with the average size of 23.49±10.49 nm. Similarly, EDS showed a strong typicalmetallic silver nanocrystallites absorption peak at 3.0 keV. The PAgNPs activate the AMP activity in MDR E. coli, M. luteus, K. pnuemoniae, and C. difficile. Conclusions: The present findings suggest that PAgNPs can be considered a suitable candidate for developing novel antibacterial drugs to combat the growing threat of antibiotic resistance. [ABSTRACT FROM AUTHOR]

Low activation isotopic boron (11B) based magnesium diboride (Mg11B 2) superconductors doped with biomass-derived activated carbon were synthesized using 11B and magnesium powder via solid-state reaction. The effect of carbon doping on the lattice structure and superconducting properties of Mg11B 2 bulks were evaluated using X-ray powder diffraction, high resolution transmission electron microscopy, scanning electron microscopy and magnetization measurements. Precise refinement of structural parameters indicates successful substitution of carbon in Mg11B 2 bulks. The critical current density (J c) of carbon doped Mg11B 2 synthesized at 650 °C was enhanced more than two times compared with the pure Mg11B 2 bulk. Similar improvement was observed for the Mg11B 2 bulks heat-treated at 800 °C. This enhancement is due to successful substitution of biomass-derived carbon with high surface area into Mg11B 2 lattice. The flux pinning mechanism of pure and doped Mg11B 2 bulks were investigated using the Dew-Hughes model. This study provides information regarding enhancement of the J c of low activation Mg11B 2 superconductors suitable for next-generation fusion magnets. [ABSTRACT FROM AUTHOR]

The use of croconic acid disodium salt (CADS) as an organic gelator with Cd(II) salt to obtain an efficient soft-scaffold supramolecular self-healable metallogel (Cd-CADS) in N,N-dimethyl formamide (DMF) media was investigated following an ultrasonication technique. The experimentally scrutinized rheological values of the fabricated metallogel not only revealed the visco-elastic property and mechanical stiffness, but also exposed the self-healable behaviour of the gel material. Two-dimensional (2D) nanosheets of hexagonal boron nitride (h-BN) were incorporated within the gel network to obtain a 2D nanosheet dispersed metallogel of Cd(II) croconate (h-BN@Cd-CADS). The microstructural investigations of the original gel network and hexagonal boron nitride (h-BN) 2D nanosheet dispersed gel-network were performed through field emission scanning electron microscopy (FESEM) and established the interconnecting rod-like fibrous type morphological patterns and inter-connected hexagonal type rod-shaped architecture pattern, respectively. High resolution transmission electron microscopy (HRTEM) was used to visualize the morphological distinction of the Cd-CADS metallogel with the h-BN 2D nanosheets. The infrared spectral (FT-IR) outputs helped to identify the formation pathway to construct the semi-solid self-healing flexible metallogel and h-BN 2D nanosheet dispersed metallogel nanocomposite, respectively. Fascinating electronic-charge transportation was revealed in the as-fabricated Cd-CADS and h-BN@Cd-CADS metallogel-based devices. Furthermore, h-BN 2D-nanosheet-directed modulation of the non-linear rectifying feature of the supramolecular Cd-CADS-metallogel was observed, with the h-BN@Cd-CADS metallogel showing a greater rectifying property, implying that it has a higher conductivity compared to the Cd-CADS metallogel. [ABSTRACT FROM AUTHOR]

Graphene nanosheets (GNSs)/Al 2 O 3 composites were synthesized by wet milling. In this study, the effects of wet milling speed on the layer distribution, quality and conversion efficiency of graphene in GNSs/Al 2 O 3 composites were studied using scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), raman spectroscopy, fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The results show that the intensity of graphite peak decreases and the conversion efficiency of graphene increases with the increase of rotational speed in the range of 200–300 rpm, and a small amount of graphene coated Al 2 O 3 nanoparticles were found in GNSs/Al 2 O 3 composites. The number of layers (≤10 layers) of GNSs gradually increases with the increase of ball milling speed. When the rotational speed is 300 rpm, the graphene conversion efficiency is the highest. At different rotational speeds, graphene defects were the least influential marginal defects. There was no characteristic peak of graphene oxide (GO) appeared in the composite, indicating a small oxidation degree of graphene. [ABSTRACT FROM AUTHOR]

Summary: Heteroatom doping could markedly enhance the properties of carbon materials. For the precursor with nitrogen (N) heteroatom, it is difficult to fix its own N heteroatom in target products to the maximum extent by traditional methods. In this work, we take corn cob core as instance to fabricate N‐doped hard carbon with high N content by a newly developed pyrolysis‐deposition‐self‐doping (PDSD) in confined graphite canister. Compared with the traditional method of pyrolysis by placing the sample in an open corundum crucible, the N doping amount of hard carbon obtained by PDSD method in a sealed graphite canister significantly increases from 0.93 to 5.63 at%. It demonstrates the crucial function of confined graphite canister in tuning the doped heteroatom's weight of carbon matrix. The influence of two kinds of pyrolysis methods on the microstructure of the materials was systematically analyzed by X‐ray diffractometer, Raman, X‐ray photoelectron spectrometer, and high resolution transmission electron microscopy (HRTEM). Furthermore, corresponding electrochemical tests are measured as anode materials for sodium‐ion batteries and the results suggest that the product prepared by PDSD method exhibits better cycling and rate performance. This fully proves the advantages of PDSD method for improving the amount of heteroatom doping, and lays the experimental and theoretical foundation for the future research and development of heteroatom doped carbon materials. [ABSTRACT FROM AUTHOR]

Summary: The present work aims to produce decanal from the dehydrogenation (DH) of 1‐decanol with CO2 as soft oxidant over copper catalysts. The main advantage of Cu catalysts is that they can promote DH and reverse water gas shift reactions, which are part of oxidative DH of 1‐decanol in presence of CO2. For this purpose, various supported Cu catalysts (Cu/MgO, Cu/CeO2, Cu/ZnO, and Cu/ZrO2) have been prepared using K2CO3 as precipitating agent. The catalysts were characterized by X‐ray Diffraction (XRD), brunauer‐emmett‐teller (BET) surface area, high resolution transmission electron microscopy, X‐ray photoelectron spectroscopy, H2‐temperature programmed reduction, UV–vis diffuse reflection spectroscopy (DRS), and CO2‐temperature programmed desorption analysis. Catalytic activity of these catalysts has been evaluated at atmospheric pressure with CO2 as soft oxidant in a fixed bed flow reactor. The high catalytic activity by Cu/MgO catalyst was mainly attributed to the presence of basic sites and dispersion of Cu metal particles. Catalytic activity was correlated with catalysts characteristics. Highlights: CO2 as a soft oxidant prevents over oxidationCO2 reacts with H2 produced via reverse water gas shift reaction (RWGSR)Copper catalysts are known to be active for both dehydrogenation and RWGSRsThe basic sites and interactions between Cu and MgO in Cu/MgO catalyst are responsible for high activity10Cu/MgO catalyst can be regenerated with, little activity loss [ABSTRACT FROM AUTHOR]

Flexural behavior of red deer's (Cervus Elaphus) antler is managed by not only orientation of osteons but also age, number density of fully fledged Cross-Linking Fibers (CLFs) and mineralization. Although crack propagation is affected by all these factors, a possible role of CLFs during the deformation remains rather disguised. The aim of this study was to enlighten the effect of dimensions, micro skeleton and mineral content of CLFs on plastic deformation. Therefore, mechanical properties, microarchitecture and mineralization of fracture sites of deer antlers were investigated using three-point bending tests in 32 specimens followed by high resolution scanning electron microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). The bending tests show that maximum bending strength is in the range of 150–177 MPa, and elastic modulus approximates to 5–6 GPa. Furthermore, fracture toughness of the test specimens examined for all branching groups of antlers was 8–9 MPa · m 1 / 2 . Age and the number of branching albeit are main reasons for differentiating microarchitecture and varying mechanical properties. SEM analyses show that a hierarchical architecture from bottom to up exists, in which some feathers and nano-sized fibrils are attached to larger fibrils that brings CLFs altogether. Antlers of adolescent deers are supposed to have shorter and thinner cross-linking fibers than elder ones. Some feathered micro-fibrils were identified across the CLFs connecting osteons. The thickness (270.0–320.0 nm) and length (700 nm) of feathers were strictly proportional to the microfibrils' size (10.0 µm in length and 1.0 µm in thickness). Furthermore, weight percentages of minerals varies along the CLFs that taking root on osteons by a bundle of many smaller fibrils whereas Pb, Cd and Hg have the highest values at the tip of broken CLFs. Such high values of these brittle elements lead to cracked ligament bridging as well. [ABSTRACT FROM AUTHOR]

To explore the effect of heterojunction on photocatalytic activity, pure Bi5O7NO3,α-Bi2O3Chanel triphase heterojunction were synthesized using hydrothermal method with Bi(N03)3 • 5H2O as raw materiaL X-ray diffraction (XRD), Raman spectroscopy, high resolution transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) were used to characterize the crystal structures and phase compositions. The result showed that after 90 min light irradiation of 250 W mercury lamps, the Rhodamine B degradation efficiency of heterojunction and Bi5O7NO3 are 98. 1% and 89. 9%. The values are far higher thanα-Bi203 25% and &@946;-Bi203 45%. The methyl orange degradation efficiency of these two samples are about 90%, faster than 77% ofα-Bi2O3 and 86% of β-Bi2O3. According to band gap and Mott-Schottky curve, Bi5O7NO3, α- and β-Bi2O3 form a staggered energy band configuration. Photogenerated electrons transfer from the conduction band of Bi5O7NO3 to the α-Bi2O3 and β-Bi2O3 conduction bands in tuni. The electron and hole is separated to improve the photocatalytic activity. Scanning electron microscopy (SEM) and diffuse reflectance spectroscopy show that the morphology and double absorption further enhance the photocatalytic activity. Therefore high activityBi5O7 NO3 photocatalyzer is in situ grown. [ABSTRACT FROM AUTHOR]

Magnetoplumbite barium hexaferrite (BaFe 11.8 Co 0.2 O 19) is synthesised through sol-gel auto-combustion method under two pH conditions of precursor solutions (acidic i.e. pH < 1 and neutral i.e. pH = 7). The XRD analysis followed by Reitveld refinement indicates the formation of phase pure samples in both cases but the barium hexaferrite obtained from acidic precursor solution has smaller crystallite sizes. The Transmission Electron Microscopy (TEM) analysis followed by High Resolution Transmission Electron Microscopy (HRTEM) confirms a lower particle size of ∼20 nm for barium hexaferrite synthesised from acidic pH precursor solution. The shift in Raman peak (520-540 cm−1) by 20 cm−1, represents the whole structural block and further confirms the differences in the distribution of particle sizes due to the method of synthesis. The magnetic studies display a lower coercive field for the samples with smaller particle sizes. This is due to the crystalline size-induced microstrain that controls the magneto-crystalline anisotropy, shape anisotropy and stress anisotropy. The electromagnetic characterisation confirms broader absorption in the range of 8–18 GHz (X -band) with R L ≤ −7 db for the entire range for the samples with smaller particle sizes. [ABSTRACT FROM AUTHOR]

Two different types of shear bands generate in ultrafine-grained (UFG) CoCrFeMnNi high-entropy alloys deformed at 77 K, i.e. commonly-observed low angle grain boundary (LAGB) type and unusual twin-coupled type. Twin-coupled shear bands exhibit a misorientation of 56–67° with the matrix, in contrast to the LAGB shear band with a misorientation of 6–12°. Both annealing twins and deformation twins can act as precursor for twin-coupled shear bands, where dislocation accumulation along twin boundaries can tune the orientation of twin lamella. These observations suggest that twin-coupled shear bands can act as an important plastic carrier in materials deformed under extreme conditions. Atomic structure of twin-coupled shear band is unveiled in an UFG CoCrFeMnNi HEA deformed at 77 K, which involves in dislocation-twin boundary coupled mechanism, based on delicate structural characterization via high resolution transmission electron microscopy. [ABSTRACT FROM AUTHOR]

In the present work, we report the biosynthesis of Nickel oxide (NiO) nanoparticles using Senna auriculata aqueous flower extract and their evaluated to the photocatalyst and antimicrobial activities. The synthesized nanoparticles were analysed using UV–Visible (UV–Vis), X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Photoluminescence (PL), High resolution transmission electron microscopy (HR-TEM), Dynamic light scattering (DLS), Zeta potential (ZE) and Surface area analysis. The XRD shows the obtained peaks are indexed to the crystalline planes (111), (200), (220), (311) and (222) confirmed that the NiO nanoparticles possessed a good crystalline nature. UV–Vis confirmed that NiO nanoparticles had a direct bandgap at 3.25 eV. DLS analysis and ZE values validated the stability of NiO nanoparticles (53 nm and − 24 mV). HR-TEM analysis revealed that the synthesized NiO nanoparticles had a spherical structure with uniform distribution along the surface. The FT-IR analyses show that the surface of synthesized nanoparticles acts as a reducing and stabilising agent for proteins, carboxyl and hydroxyl groups. The antibacterial activities of biosynthesized NiO nanoparticles are greater against Gram-negative (Escherichia coli) than the Gram-positive microorganism. The catalyst activity of synthesized nanoparticles regarding methylene blue (MB) dye degradation under direct visible light irradiation was studied. The degradation effectiveness against MB dye was found to be 97% for 90 min. Overall, these studies show that Senna auriculata is an effective sell being planted and has the highest probability of being used in the design and development of nanoparticles for environmental pollution and human health. [ABSTRACT FROM AUTHOR]

Endovascular treatment with stent retriever thrombectomy is a major advancement in the standard of care in acute ischemic stroke (AIS). The modalities through which thrombi embed along stent retriever following mechanical thrombectomy (MTB) have not yet been elucidated. Using scanning electron microscopy (SEM), we analyzed the appearance of thrombi retrieved by MTB from AIS patients, when embedded into the stent retriever. We observed that the organization and structural compactness vary for compositionally different thrombi. The modalities of attachment onto the stent vary according to thrombus composition and organization. [ABSTRACT FROM AUTHOR]

In this manuscript, a novel dual-step selective epitaxy growth (SEG) of Ge was proposed to significantly decrease the defect density and to create fully strained relaxed Ge on a Si substrate. With the single-step SEG of Ge, the threading defect density (TDD) was successfully decreased from 2.9 × 107 cm−2 in a globally grown Ge layer to 3.2 × 105 cm−2 for a single-step SEG and to 2.84 × 105 cm−2 for the dual-step SEG of the Ge layer. This means that by introducing a single SEG step, the defect density could be reduced by two orders of magnitude, but this reduction could be further decreased by only 11.3% by introducing the second SEG step. The final root mean square (RMS) of the surface roughness was 0.64 nm. The strain has also been modulated along the cross-section of the sample. Tensile strain appears in the first global Ge layer, compressive strain in the single-step Ge layer and fully strain relaxation in the dual-step Ge layer. The material characterization was locally performed at different points by high resolution transmission electron microscopy, while it was globally performed by high resolution X-ray diffraction and photoluminescence. [ABSTRACT FROM AUTHOR]

The main objective of the present study is to develop artificial neural networks (ANN) to predict the adsorption efficiency of multi-walled carbon nanotubes (MWCNTs) on Cr(VI) removal. Polydisperse MWCNTs were synthesized at 750 °C on alumina supported Fe-Co-Mo catalyst using CVD (chemical vapor deposition)-assisted spray pyrolysis of Azadirachta indica (Neem) oil under inert Argon (Ar) atmosphere. Growth of MCWNTs with inner diameters between 9 and 14 nm was corroborated by scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), X-ray diffraction analysis (XRD), and Raman spectral evidence assessments. The metal-ion adsorbent capacity (Cr-VI) of the as such prepared MWCNTs was examined for industrial purposes. Different parameters such as adsorption isotherms, kinetics, and thermodynamic parameters were analyzed for the removal of metal ions with MWCNTs. The results of isotherm, kinetic, and thermodynamic study indicated that the process suited well with Langmuir isotherm, pseudo second-order kinetics, and followed endothermic reaction, respectively. The effects of parameters such as adsorbent dosage, concentration of chromium ion (Cr-VI), pH, and contact time were studied to optimize the maximum removal of Cr(VI). In order to optimize the process conditions using Artificial Neural Networks, Box-Behnken design (BBD) was used to design the batch adsorption experiments, and the resulting datasets were used as the input for ANN. To predict the adsorption efficiency, various ANN architectures were examined using different training algorithms, number of neurons in the hidden layer, and the transfer function for the hidden and output layers. A neural network structure with Levenberg–Marquardt (LM) training algorithm, 14 hidden neurons, and tangent sigmoid transfer function at the hidden layer and logarithmic sigmoid transfer function at the output layer furnished the best level of prediction results. Comparing with experimental data, the optimal model capitulated mean square error (MSE),and correlation coefficient (R2) of 0.0324 and 0.99512, respectively. The results showed that ANN is well-organized in predicting the adsorption efficiency of MWCNTs for Cr(VI) metal ion removal process. [ABSTRACT FROM AUTHOR]

This article discusses the direct effect of the seed layers on the growth of the ZnO nanorods (ZNRs) and related photovoltaic parameters of the hybrid perovskite solar cell (PSC). Four different types of ZnO seed layer samples are prepared to analyze the growth of ZNRs over the respective seed layers. Various device parameters for the respective PSCs made of different seed layers are investigated. The ZnO quantum dot-based seed layer shows the well-aligned, vertical, and uniform distribution of ZNRs and improves SC parameters over the other three samples. The ZnO seed layer deposited via drop cast methods results in less density, random, and nonuniform distribution of the ZNRs. The surface morphology, optical absorption, transmission, and crystalline structure were analyzed with high resolution scanning electron microscopy (HRSEM), TEM, UV-visible absorption, and X-ray diffraction (XRD) techniques. 10.69% of power conversion efficiency with improved open-circuit voltage (${V}_{OC}$) of 1.01 V is achieved for device structure, fluorine doped tin oxide (FTO)/ZnO QDs seed layer/ZNRs/perovskite/poly[bis(4-phenyl)(2,5,6-trimethylphenyl)amine (PTAA)/gold (Au). [ABSTRACT FROM AUTHOR]

Owing to their autocatalytic properties, gold nanoparticles (AuNPs) are used in biomedical applications. While their usage in neurodegenerative disease control, diabetes, etc. has been documented, their function is mostly untapped in cardiovascular disease treatment. Hence, in this work is the leading to combine, classify and test cardiomyoblast hypertrophy efficiency of AuNPs. In the case of AuNPs, the Imperata cylindrica extracts (IPC) and gold solution (HAuCl4) were fabricated with 1:5 volume ratios and were distinguished by specific processes, such as ultraviolet–visible (UV–vis) spectroscopy, scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). The radical scavenging of superoxide and hydroxylic AuNPs has been shown to be stronger relative to bulk gold and extracts. In cell line tests, rat cardiomyoblasts H9c2 and 3T3 fluorescence were used in this work. The generation of intracellular superoxide anion was less due to the incubation of greater AuNPs levels. In addition, preliminary findings gave an insight into the role of AuNPs in attenuating cardiomyoblastic induced isoproterenol hypertrophy. [ABSTRACT FROM AUTHOR]

To study the effect of polyethylene glycol capping on structural, optical and thermal properties, ZnS:Ni2+ nanoparticles have been prepared by chemical precipitation method. It is demonstrated that by varying the concentration of PEG the particle size can be varied within ∼3.58 to 12 nm. To analyze the samples of nanostructures, the samples are subjected to X-ray diffraction, Field emission scanning electron microscopy and High resolution transmission electron microscopy characterization techniques. The spectral bands between 673 and 494 cm−1 are related to Zn-S stretching vibrations which was confirmed by Fourier transform infrared spectral studies. It is found that the uncapped sample emits strong UV light, whereas the capped samples exhibit strong and broad visible emission. An enhancement of fluorescence intensity has been obtained, in a capped sample with the minimum particle size and thus with more defect centers, in comparison to that of uncapped one. [ABSTRACT FROM AUTHOR]

In this paper, the role of antimony (Sb) as a dopant in single-phase bulk Cu2ZnSnSe4 (CZTSe) has been studied. The sb-doped CZTSe bulk material has been synthesized via facile mechanical dry ball milling method. The structural characterization and phase formation were studied through X-ray diffraction (XRD) and Raman spectroscopy. Particle size and electron diffraction measurements were done using high resolution transmission electron microscopy and selected area electron diffraction. Field emission scanning electron microscope and energy dispersive X-ray spectroscopy analyses have been done to infer morphology and composition. Oxidation state of constituent elements in milled powder was studied by X-ray photoelectron spectroscopy analysis. The results of XRD and Raman results are suggestive that the dry milling is a reliable method for the synthesis of single-phase CZTSe. It is also possible to achieve doping with low concentrations of Sb during the milling process to obtain sb-doped bulk single-phase CZTSe. [ABSTRACT FROM AUTHOR]

A copolymer of poly(BuMA–co–EDMA) modified with C-tetra(nonyl)calix[4]resorcinarene was obtained via the impregnation method. The formation of the modified copolymer was confirmed and investigated using various techniques; in this way, the presence of calix[4]resorcinarene was confirmed by FT-IR spectroscopy and by high resolution transmission electron microscopy. The modified copolymer was used for the removal of highly toxic cations (Pb2+, Hg2+, and Cd2+) from aqueous solutions. To perform the removal, we used the batch sorption technique and the effects of time of contact, pH, and volume of sample on the effective sorption were determined. The best results were observed for Pb2+ extraction, which was comparatively more efficient. Adsorption–desorption experiments revealed that the modified copolymer could be used for several cycles without significant loss of adsorption capacity. Finally, the results showed that the modified copolymer application is highly efficient for the removal of lead ions from aqueous solutions. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) is a sp2 hybridized carbon atom arranged in a honeycomb lattice. Graphene is a new allotrope of carbon compound which could prime new openings in research fields. GO was successfully synthesized via Phyllanthus Emblica (PE) leaf. Structures, morphologies and photo catalytic activities of the as synthesized nanomaterial were determined by using X-Ray diffraction (XRD), UV-Visible spectroscopy, Field emission scanning electron microscopy (FE-SEM), Energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), High resolution transmission electron microscopy (HRTEM) analysis. The photo catalytic activities of the as-synthesized GO were estimated for the degradation of malachite green (MG) and methyl violet (MV) in aqueous solution under replicated solar light. The photo catalytic degradation of GO was 94% for brilliant green and 99% for methyl violet in 120 min. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are sought after by many industries including food industries, heavy metal sensing, pharmaceutical, and textile. The present study reports on the biosynthesis of silver nanoparticles (AgNPs) and theirs antibacterial activity using a methanolic leaf extract of Heteropyxis natalensis, a native South African medicinal tree. The synthesised particles were characterised by ultraviolet visible spectroscopy (UV-vis), energy dispersive Xray spectroscopy (EDX), high resolution transmission electron microscopy (HRTEM), and Fourier transform infrared spectroscopy (FTIR). A colour change of the reaction solution from yellow to brown preliminarily confirmed the presence of AgNPs, and a single absorbance peak at 422 nm, using UV-vis spectroscopy, was the indicative of AgNPs. While EDX revealed the presence of elemental silver in the sample, HRTEM identified spherical AgNPs ranging from 5-60 nm. Hydroxyls, alkynes, alkenes, alkanes, esters, and alkyl halides as possible capping agents of silver ions (Ag+) into AgNPs were identified by FTIR. In addition, AgNPs exhibited antibacterial efficacy against 5 strains of pathogenic bacteria: Escherichia coli, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus subtilis. The results obtained in this study could potentially benefit future research in nanomedical-driven fields. [ABSTRACT FROM AUTHOR]

The present report presents a green method for the rapid biogenic synthesis of nanoparticles that offers several advantages over the current chemical and physical procedures. It is easy and fast, eco-friendly, and does not involve any precious elements, hazardous chemicals, or harmful solvents. The synthesized ZnO nanoparticles were characterized using different techniques, such as UV-Visible spectroscopy. The surface plasmon resonance confirmed the formation of ZnO nanoparticles at 344 nm, using UV-Visible spectroscopy. The leaf extract acts as a source of phytochemicals and is primarily used for the reduction and then the formation of stable ZnO nanoparticles by the characteristic functional groups of the extract; the synthesized ZnO nanoparticles were identified using FTIR spectroscopy. The crystalline nature of ZnO-NPs was confirmed via powder X-ray diffraction (XRD). Size and morphology were measured via high resolution transmission electron microscopy (HR-TEM) analysis. The stability of the nanoparticles is established using dynamic light scattering (DLS) and thermogravimetric analysis (TGA). The synthesized ZnO nanoparticles have been found to be a good and efficient catalyst for the synthesis of novel 1,2-dihydro quinazoline derivatives under the green method via a one-pot reaction of 2-amino benzophenone, 1,3-diphenyl-1H-pyrazole carbaldehydes, and ammonium acetate. The synthesized compounds (4a–o) were characterized by the 1H NMR, 13C NMR, and HRMS spectra and were further validated for free-radical scavenging activity. The synthesized ZnO nanoparticles exhibited good antioxidant activity. [ABSTRACT FROM AUTHOR]

Multiferroic (x)BaTiO3/(1 − x)Li0.5Fe2.5O4 (0.0 ≤ x ≤ 1) perovskite/spinel nanocomposite was synthesized using a modified citrate auto-combustion method. Both BaTiO3 (BTO) and Li0.5Fe2.5O4 (LFO) phases along with their composites were successfully characterized using X-ray diffraction, Fourier transformation infrared spectroscopy, and X-ray absorption fine structure spectroscopy. The nanoscale, morphology, and magnetic properties were imaged and acquired using high resolution transmission electron microscopy, atomic force microscopy, and vibrating sample magnetometer. Synchrotron radiation-based elemental selective XAFS technique was performed around Fe K-edge to obtain the selective and the detailed local structural information of Li0.5Fe2.5O4 nanoparticles (NPs). The main remarkable result in this work is the enhancement in the coercivity (HC) of LFO NPs after compositing with BTO particularly at x = 0.6, and at x = 0.8. Based on the collected results, BTO/LFO nanocomposite can be seen as a good candidate for different technological applications including magnetically modulated piezoelectric, safety rechargeable batteries, and multilayer ceramic capacitor. [ABSTRACT FROM AUTHOR]

Antiferroelectrics (AFEs) undergo reversible antiferroelectric-ferroelectric (AFE-FE) phase transitions under external electric fields, and show great promise in modern electronic devices. The real-time phase transition behavior of pure PZO has been detected, while the dynamic studies of complex incommensurately modulated structure have never been addressed. Here, with the strong support of in-situ aberration corrected high resolution transmission electron microscopy (AC-HRTEM), the structural evolutionary behaviors in Pb 0.96 La 0.04 (Zr 0.95 Ti 0.05)O 3 (PLZT) film excited by energetic electron beams is decoded. The AFE-to-FE phase transition occurs via a 90° reorientation and a rapid expansion of domain boundary region at the expense of the initial AFE matrix. At the same time, the modulation periods experience a monotonic increase in the reorientation region. The observation is of certain significance to establish the deep-seated phase transition mechanism, which will facilitate the development of antiferroelectric-based nanoelectronics. [Display omitted] [ABSTRACT FROM AUTHOR]

• NiO/MoS 2 /rGO ternary nanocomposites were synthesized via microwave-assisted reflux method. • NiMG-50 is studied towards sonocatalytic, photocatalytic and sono-photocatalytic degradation. • NiMG-50 composite exhibited superior sono-photocatalaytic degradation of TTC and CIP. • ̇ OH and ̇ O 2 – radicals are the primary active agents participating in the degradation of the antibiotics. • The NiMG-50 has a Z-scheme charge transfer and migration mechanism. In this study, NiO-MoS 2 /rGO nanocomposites were synthesized successfully by a simple microwave assisted refluxing method by varying the mass ratios of rGO. The NiMG-50 ternary nanocomposite has been applied by sonocatalytic, photocatalytic and sono-photocatalytic degradation for the removal of tetracycline (TTC) and ciprofloxacin (CIP) antibiotics. Physicochemical properties of the synthesized samples were characterized by Powder X-ray Diffraction (PXRD), Energy Dispersive X-ray Spectroscopy (EDAX) and X-ray Photoelectron Spectroscopy (XPS) corroborated the phase purity of NiMG-50 nanocomposite. The High Resolution Scanning Electron Microscopy (HR-SEM) image reveals the zigzag arrangements of NiO nanoflakes over MoS 2 and rGO sheets. The tight contact of platelet shaped-NiO NP's and curled layer-MoS 2 on the sheets of rGO results in the separation of photo-induced e--h+ pairs as demonstrated by the High Resolution Transmission Electron Microscopy (HR-TEM) analysis. Optical properties reveal a reduced band gap and enhanced separation efficiency with fast charge transfer rate, improving the organic pollutant degradation efficiency. NiMG-50 demonstrated a good catalytic activity against TTC and CIP in sono-photocatalytic process with an efficiency of 94.10 % and 83.96 % at 35 and 90 min, respectively. Simultaneously, the experimental results showed that the NiMG-50 composite follows the pseudo-first order reaction kinetics with a rate constant (K SP) value of 0.077 min−1 and 0.015 min−1 for TTC and CIP. The radical trapping test and degradation mechanism indicated that the continuous contribution of ̇ OH and ̇ O 2 – reactive radicals are the major ones responsible for the active involvement in the degradation reaction. This research work gives a fresh prospects to the as prepared NiMG catalyst as an efficient composite with a good applicability for the sono-photocatalytic degradation of pharmaceutical products. [ABSTRACT FROM AUTHOR]

[Display omitted] • Developed a fluorescence turn-off sensor based on benzyl amine capped perovskite (CH 3 NH 3 PbBr 3) quantum dots for the detection of Bilirubin (LOD = 0.42 μM). • Steady state and time correlated spectroscopic studies were conducted to investigate sensing mechanism. • The sensing mechanism is based on Forster Resonant energy transfer (FRET) due to the considerable spectral overlap between absorption spectra of Bilirubin and emission spectra of perovskite quantum dots. Luminescent organic–inorganic metal halide hybrid perovskite quantum dots (PQDs) as a new class of fluorophores are finding increasing attention towards chemical and biological sensing due to their exceptional photophysical properties. Herein, we synthesized highly fluorescent CH 3 NH 3 PbBr 3 perovskite quantum dots (B-PQDs) through the ligand assisted reprecipitation method (LARP), using benzylamine as the surface capping ligand. Morphological and opto-structural properties of the as-synthesized B-PQDs were thoroughly investigated using high resolution transmission electron microscopy (HR-TEM), X-Ray diffraction (XRD), Fourier transform infra-red spectroscopy (FT-IR), UV–Vis absorption, and fluorescence spectroscopy. The as-synthesized electron-rich amine-capped B-PQDs were employed to study their sensing response towards bilirubin (BL). The aromatic amine capped B-PQDs enhance the sensory response towards BL due to the π-π interaction with BL's conjugated system. The B-PQDs were found to be highly sensitive towards BL with a stern–volmer constant value ≈ 4.3 × 104 M−1 and limit of detection of 0.42 μM. A panel of characterizations were carried out to investigate the detailed sensing mechanism where resonance energy transfer was found to be the dominant quenching mechanism for BL detection. Our results demonstrated the potential for utilizing organic–inorganic halide perovskite quantum dots for sensing applications, through surface ligand modification tailored for detecting specific analytes. [ABSTRACT FROM AUTHOR]

The cell structures and mechanical properties (i.e., hardness, Young's modulus, shear modulus, and Poisson's ratio) of (Hf 0.2 Zr 0.2 Ti 0.2 Nb 0.2 Ta 0.2)C (HEC) and (Hf 0.2 Zr 0.2 Ti 0.2 Nb 0.2 Ta 0.2)N (HEN) high-entropy ceramics were simulated by special quasi-random structure (SQS) and general random structure (GRS) with atomic occupation preference based on the first-principles density functional theory. The results show that compared to SQS, the cell structure constructed by GRS is more realistic, which is verified via scanning electron microscopy, high resolution transmission electron microscopy and energy dispersive spectroscopy. The mechanical properties simulated by GRS were also determined by microhardness and dynamic elastic modulus testers. The hardness, Young's modulus，shear modulus and Poisson's ratio predicted by GRS are 23.07 GPa, 449.71 GPa, 183.28 and 0.227 for HEC and 22.96 GPa, 413.71 GPa, 162.47 and 0.241 for HEN, which are in a reasonable agreement with the measured results (i.e., 22.05 ± 0.32 GPa, 433 ± 12 GPa, 172 ± 18 GPa, 0.21 for HEC and 22.12 ± 0.13 GPa, 372 ± 23 GPa, 158 ± 11 GPa, 0.23 for HEN). This work can provide a promising reference for preparing high-entropy non-oxide ceramics via the prediction. • Atomic occupancy-based structure is used to analyze atomic preference occupancy within high-entropy non-oxide ceramics. • Crystal structure of high-entropy non-oxide ceramics is predicted besides experimental validation. • Simulated and measured mechanical properties of high-entropy carbide and nitride bulk ceramics are analyzed. [ABSTRACT FROM AUTHOR]

Inspired by the bionic idea, the AlCrTiN/6061 laminated composite material with "mortar and brick" structure was fabricated by one-pass rolling. And the interface characteristics, dry friction process and wear mechanism of the nacre-like AlCrTiN/6061 laminated composite were systematically studied. Scanning electron microscopy (SEM) confirmed the successful construction of the "mortar-brick" structure in the composite. And high resolution transmission electron microscopy (HRTEM) revealed that Al 18 Cr 2 Mg 3 phase is formed at the interface of AlCrTiN/6061 laminated composite. Electron back scatter diffraction (EBSD) analysis showed that there are 〈110〉 silk texture in the RD direction. Moreover, the tribological tests indicated that the friction coefficient (COF) of the laminated composites ranged from 0.379 to 0.437, which can meet the requirements of lightweight and high-performance braking of automobiles. [Display omitted] • The AlCrTiN/Al6061 laminated composite was fabricated by one-pass rolling. • The AlCrTiN/Al6061 laminated composite has a "mortar and brick" structure. • The Al 18 Cr 2 Mg 3 phase was formed at the interface of AlCrTiN/Al6061 composite. • The friction coefficient of AlCrTiN/Al6061 composite improved about 20 %. [ABSTRACT FROM AUTHOR]

• Micromechanical properties of coals of different coal grades were explored. • The evolutionary characteristics of the nanocarbon structure of coals are investigated. • The relationship between nanocarbon structure and micromechanical properties is discussed. The micromechanical properties of coals are key parameters affecting the development of coalbed methane (CBM). In order to understand the relationship between the micromechanical properties and the nanocarbon structure of coals, high resolution transmission electron microscopy (HRTEM) and nanoindentation were used to investigate the micromechanical properties of vitrinite in different coals and the response to changes in nanocarbon structure. Coals with higher coal rank have greater elastic modulus and hardness. The end-of-loading displacement and creep displacement decrease with the increase of coal rank, both of which have a good negative correlation with the elastic modulus and hardness. Fringe length, degree of orientation, proportion of straight fringes, and proportion of stacks all increase with increasing coal rank. The curvature of the fringes decreases with increasing coal rank. The variation of the nanocarbon structure has an important effect on the micromechanical properties. The nanocarbon structure parameters of fringe length, proportion of straight fringes, degree of orientation, and proportion of stacks have good linear relationships with the micromechanical parameters of elastic modulus and hardness. In addition, this study analyzes the effect of the micromechanical properties of coal on the effectiveness of the proppant. Therefore, the evolution of the nanocarbon structure should be emphasized in future studies on the micromechanical properties of coal. [ABSTRACT FROM AUTHOR]

• Hard/soft nanocomposites were prepared by one-pot sol–gel auto-combustion technique. • The composition exhibited a good exchange-coupling. • Strong correlation between the chemical composition and electrodynamic parameters. This work presented the effect of Ho substitution on magnetic and electrodynamic properties of hard-soft SrBaHo x Fe 12-x O 19 @NiFe 2 O 4 (x ≤ 0.06) nanocomposites (H/S Ho → SBFeO@NFO NCs) which were produced through one-pot citrate sol–gel method. The structure and morphology were explored using X-ray diffractometry (XRD) and scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HR-TEM). By scrutinizing hysteresis curves at temperatures of 300 K (Room temperature, RT) and 10 K, the magnetic characteristics of H/S Ho → SBFeO@NFO (x ≤ 0.06) NCs have been investigated. These materials display smooth, open hysteresis loops at both temperatures, indicating their ferrimagnetic nature and highlighting the presence of exchange-coupling interactions within the nanocomposites. The SQR (squareness ratio) values, below 0.5 at both high and low temperatures, indicate a multi-domain structure in the H/S Ho → SBFeO@NFO (x ≤ 0.06) NCs. Magnetic parameters demonstrate fluctuations with growing Ho content. The introduction of Ho3+ ions notably reduce the coercivity of the undoped H/S Ho → SBFeO@NFO (x ≤ 0.06) NCs. Saturation magnetization (M s) and magnetic moment show similarity between undoped and Ho-doped nanocomposites at all concentrations, except for x = 0.06, where a considerable decrease occurred at both temperatures. Our findings propose that by controlling the concentration of Ho3+ ions, the magnetic properties of H/S Ho → SBFeO@NFO NCs can be precisely adjusted. Electromagnetic properties of the H/S Ho → SBFeO@NFO NCs were investigated in the range 33–50 GHz. Frequency dispersions of the real/imaginary parts of permittivity and permeability were determined from S11 to S21 parameters. RL coefficient demonstrated intensive electromagnetic absorption with average level −16...−23 dB in this frequency range that corresponded to the absorption of the natural media. [ABSTRACT FROM AUTHOR]

The oxygen reactivity of propane flame soot in a filter cake was systematically investigated, considering the morphological properties of the particles. A scanning mobility particle sizer (SMPS), high resolution transmission electron microscopy (HRTEM) and Raman spectroscopy were used to determine the initial aggregate size, the primary particle size, and the nanostructure of the soot particles. The samples were analyzed using an experimental setup, which enables oxidation and in-situ measurement of the BET surface, revealing its development as the reaction progresses. Particles with five different mobility diameters were generated using a combustion aerosol standard (CAST) soot generator. While the nanostructure of the particles was similar at four operating points, the particles with the smallest mobility diameter differed as they were more amorphous, which was consistently seen in HRTEM images and Raman spectra. The results showed that for the particles with similar nanostructure, the mobility diameter, the size of the primary particles and the initial surface area correlate. These particles have similar oxygen reactivity. The amorphous particles instead, showed a significantly higher reactivity, despite having the lowest specific surface area. The nanostructure appears to be decisive for the reactivity. Further the results clearly showed that surface area development affects the soot conversion profiles. Surface-normalized reaction kinetics for soot at each operation point were formulated. [Display omitted] [ABSTRACT FROM AUTHOR]

Polydopamine (PDA)-coated Zn–Al-layered double hydroxide (Zn-Al LDH@PDA) have been synthesized through a simple and green procedure. In the present study, for the first time, Pd nanoparticles were successfully deposited using Zn-Al LDH@PDA as an efficient reducing biotemplate and stabilizing support. In this protocol, Pd ions were adsorbed on surfaces of Zn-Al LDH@PDA through immersion of the Zn-Al LDH@PDA nanocomposite into a palladium plating bath. Next, they were reduced in situ to palladium nanoparticles using PDA’s N-containing groups and reducing ability. The structure, morphology and physicochemical properties of the synthesized nanoparticles were characterized by different analytical techniques such as energy-dispersive X-ray spectroscopy (EDS), field emission scanning electron microscope (FE-SEM), Fourier-transform infrared spectroscopy (FT-IR) spectroscopy, transmission electron microscopy (TEM), high resolution transmission electron microscopy (HR-TEM), fast Fourier transform (FFT),inductively coupled plasma (ICP), nitrogen physical adsorption (BET), elemental mapping and X-ray Diffraction (XRD).The catalytic potential of Zn-Al LDH@PDA/Pd NPs nanocatalyst was then evaluated in the Suzuki–Miyaura coupling reactions. These tests indicated that Zn-Al LDH@PDA/Pd NPs nanocatalyst is tolerant against various functional groups, and the desired biphenyl products were acquired with good to high yields within short times. The Zn-Al LDH@PDA/Pd NPs nanocatalyst was isolated by centrifuge and it was stable enough to be reused for 7 consecutive times without considerable loss in activity.Graphical Abstract: Polydopamine (PDA)-coated Zn–Al-layered double hydroxide (Zn-Al LDH@PDA) have been synthesized through a simple and green procedure. In the present study, for the first time, Pd nanoparticles were successfully deposited using Zn-Al LDH@PDA as an efficient reducing biotemplate and stabilizing support. In this protocol, Pd ions were adsorbed on surfaces of Zn-Al LDH@PDA through immersion of the Zn-Al LDH@PDA nanocomposite into a palladium plating bath. Next, they were reduced in situ to palladium nanoparticles using PDA’s N-containing groups and reducing ability. The structure, morphology and physicochemical properties of the synthesized nanoparticles were characterized by different analytical techniques such as energy-dispersive X-ray spectroscopy (EDS), field emission scanning electron microscope (FE-SEM), Fourier-transform infrared spectroscopy (FT-IR) spectroscopy, transmission electron microscopy (TEM), high resolution transmission electron microscopy (HR-TEM), fast Fourier transform (FFT),inductively coupled plasma (ICP), nitrogen physical adsorption (BET), elemental mapping and X-ray Diffraction (XRD).The catalytic potential of Zn-Al LDH@PDA/Pd NPs nanocatalyst was then evaluated in the Suzuki–Miyaura coupling reactions. These tests indicated that Zn-Al LDH@PDA/Pd NPs nanocatalyst is tolerant against various functional groups, and the desired biphenyl products were acquired with good to high yields within short times. The Zn-Al LDH@PDA/Pd NPs nanocatalyst was isolated by centrifuge and it was stable enough to be reused for 7 consecutive times without considerable loss in activity. [ABSTRACT FROM AUTHOR]

Affordable and swiftly available h-BN@SnO 2 /TiO 2 photocatalysts are being developed through an easy hydrothermally approach was used urea as boric acid precursors. With their constructed photo catalysts, the effect of h-BN@SnO 2 /TiO 2 has been investigated under the assessment of Adsorption agents utilizing X-ray diffraction pattern (XRD), Scanning electron microscopy, Energy dispersive spectroscopic analysis (SEM/EDS), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HR-TEM), and Burner Emit Teller (BET) isotherm testing methods, which also indicated that SnO 2 /TiO 2 and h-BN have been tightly bound together. Because turquoise blue (TB) and Methyl orange (MO) fabric dyes can be found in the industrial wastewater being processed, the photo catalytic degradation process happens to be applied. According to the advantageous linkages of h-BN@SnO 2 /TiO 2 photocatalysts, fantastic efficacy in breakdown towards hazardous compounds has been found. For the decomposition of Turquoise blue (TB) and Methyl orange (MO), the h-BN@SnO 2 /TiO 2 catalysts proved the best performance stability (0.0386 min−1 and 1.524min−1) but were significantly 22 times quicker. Optical catalysis has additionally demonstrated extraordinary resilience and durability throughout five reprocessed efforts. On top of that, an approach enabling photocatalytic breakdown of harmful substances upon h-BN@SnO 2 /TiO 2 has been presented. • Swiftly available h-BN@SnO 2 /TiO 2 photocatalysts are being developed through an easy hydrothermally approach. • Photocatalytic Adsorption agents of h-BN@SnO 2 /TiO 2 has been investigated utilizing XRD, SEM/EDS, TEM, HR-TEM, and BET isotherm testing methods. • h-BN@SnO 2 /TiO 2 photocatalysts on photocatalytic Debasement of textile cloth dyes were achieved very short time 60 and 80min respectively. • The rate of overlap among protons engaging photon and defects By EIS analysis. [ABSTRACT FROM AUTHOR]

Chemical vapor deposition (CVD) diamond coatings on WC-Co substrates have gained significant attention due to their exceptional mechanical properties and wide-ranging applications in cutting tools, wear-resistant parts, and other advanced technologies. The interface bonding between CVD diamond coatings and WC-Co substrates plays a crucial role in determining the performance and durability of the coated tools. In this paper, the characteristics of the interface microstructures between the CVD diamond coating and WC-Co substrate was investigated by high resolution transmission electron microscopy (HRTEM) and EDS. The structures were observed in the system where the diamond coating (film) was deposited on the WC-Co cemented carbide substrate using HF-CVD technology. The results indicate three types of structures at the diamond coating-substrate interface: WC/diamond, WC/graphite/diamond, and Co/graphite/amorphous carbon/diamond. The bonding mechanisms at the CVD diamond coating/WC-Co substrate interface are discussed. • FIB slice specimen depicts CVD diamond's direct interface with WC and residual Co for TEM observation was successfully prepared. • In Co residual region, graphite/amorphous carbon layers confirmed between CVD diamond crystals and substrate, as previously speculated. • Interfaces seen in Co-free areas included WC crystals directly in contact with diamonds, and others layered with nano graphite. [ABSTRACT FROM AUTHOR]

This study aims to clarify the growth process of the β-phase in Al-Mg-Si alloys from the point of view of morphological evolution. The orientation relationship, shape, growth process, misfit value, and interfacial condition between the β-phase and Al matrix were investigated using high-resolution transmission electron microscopy (HR-TEM), focused ion beam (FIB), and optical microscope (OM). In a previous study, the growth process and shape of the β-phase were determined using scanning electron microscopy (SEM). It was proposed that the truncated octahedron (8{111}, 6{100} facets) transforms into a hexahedron (6{100} facets). This study proposes that two new three-dimensional shapes of the β-phase exist between the truncated octahedron and hexahedron, and we identified the {111} β facets at the edges of the β-phase. We proposed the morphology evolution during the growth process of Mg 2 Si crystals and calculated the misfit to understand that the unstable {111} β facet has a higher misfit value compared to the {001} β and {011} β facets. Our observations provide insight into how they influence the behavior of Mg 2 Si crystals, which is crucial for predicting the microstructural evolution of Al-Mg-Si alloys and for designing materials with desired properties. • Investigated the morphology evolution of the β-phase in Al-Mg-Si alloys. • Explored β-phase orientation relationship, shape, and growth process using HR-TEM, FIB, and OM. • Discovered {111} β facets and proposed new three-dimensional shapes for the β-phase. • Calculated misfit values, revealing the instability of the (111) β facet compared to (001) β and (011) β facets. • Contributed to understanding microstructural evolution in Al-Mg-Si alloys and material design. [ABSTRACT FROM AUTHOR]

• Spinel ferrite N i 0. 4 + x Z n 0. 6 − x C e y F e 2 − y O 4 (0 ≤ x + y ≤ 0.3) were synthesized by a modified glycol-thermal process. • Correlation between saturation magnetization and the effective magnetic moments. • Crystallite sizes vary inversely with initial magnetic susceptibility. • Distinct strong correlation between inverse initial magnetic susceptibility and unit cell volume. • Compound N i 0. 4 Z n 0. 6 F e 2 O 4 exhibit best sensing characteristics. The spinel ferrite systems N i 0. 4 + x Z n 0. 6 − x C e y F e 2 − y O 4 (0 ≤ x + y ≤ 0.3) were synthesized by a modified glycol-thermal technique. X-ray diffractometer (XRD) confirmed formation of single phase cubic spinel structure with average crystallite sizes 8–21 nm. The crystallite sizes were found to be in agreement with the particle sizes obtained from the high resolution transmission electron microscopy (HRTEM) indicating formation of single domain nanoparticles. Scanning electron microscopy (SEM) showed a homogeneous spread of semi-spherical nanoparticles. Brunauer-Emmett-Teller (BET) revealed specific surface area ranging between 64 and 108 m2/g, while Barrett-Joyner-Halenda (BJH) showed the pore sizes varying between 48 and 126 nm. Cation distribution obtained from Rietveld refinement revealed all Ce3+ occupied B- sites whilst Ni2+, Zn2+, Fe3+ occupied both A and B sites. Magnetization measurements were performed using the vibration samples magnetometer (VSM). The saturation magnetization varied between 51 and 60 emu/g, while the coercivity dropped from 114 to 89Oe. The remnant magnetization varied between 3 and 12 emu/g. A correlation was observed between the saturation magnetization and the effective magnetic moments confirming cation distribution to be reliable. A strong correlation between initial susceptibility and unit cell volume was found. The crystallite sizes varied inversely with initial magnetic susceptibility. The magnetic characteristics of presented materials make them useful in high frequency device applications and has potential use as contrast agent in magnetic resonance imaging (MRI). 57Fe Mössbauer spectroscopy revealed the strengthening of ferromagnetic coupling. Gas sensing tests revealed a decrease in sensing response with the transition from paramagnetic state to ferromagnetic state. The N i 0. 4 Z n 0. 6 F e 2 O 4 sample showed the best sensing response to SO 2 at 100 °C compared to CO gas. However, at 150 °C the sample was more sensitive to CO gas than SO 2 gas. [ABSTRACT FROM AUTHOR]

• Thermomechanical fatigue leads to lower lifetime than isothermal fatigue. • Formation of persistent slip band and honeycomb networks were observed. • Transcrystalline and intercrystalline fatigue crack propagation was found. • Proportional damage from fatigue, creep, and oxidation was evaluated. Thermomechanical low-cycle fatigue (TMF) tests were performed on polycrystalline cast nickel-based superalloy MAR-M247 under in-phase (IP) and out-of phase (OP) loading in the temperature range of 500–900 °C. A constant heating and cooling rate of 5 °C.s−1 was selected. Furthermore, isothermal low-cycle fatigue (ILCF) tests with the same cycle period as TMF cycle were carried out at the maximal temperature of TMF cycle (900 °C). All tests ran under strain control and fully reversed cycle on solid cylindrical specimens in laboratory air. High resolution scanning electron microscopy and transmission electron microscopy were utilized to characterize the damage mechanism occurring during TMF and ILCF loading. The cyclic deformation and lifetime behaviour as well as damage mechanisms dependent on loading regime were examined. Results show that the TMF loading has a detrimental effect on the lifetime of MAR-M247. Lifetime reduction is most significant under IP loading. The fracture surfaces are characterized by typical striation fields, where the largest spacing between striations was observed for IP loading with prevailing intercrystalline cracking followed by OP and isothermal ILCF loading with transcrystalline crack propagation. To improve discussion of obtained results, experimental data were compared with damage and life prediction models. [ABSTRACT FROM AUTHOR]

• High temperature water combined with irradiation induces in oxidation of grain boundaries that weaken the boundaries. • Applied tensile stress enhances the rate of grain boundary oxidation. • Deformation induced dislocation channels create local stresses sufficient to crack a grain boundaryweakened by oxidation. • Fracture of the oxidized grain boundary allows for oxidation of the boundary beneath the crack tip. • Oxidation of silicon at the grain boundary forms highly soluble amorphous silica that aids crack extension via dissolution. Irradiation assisted stress corrosion cracking (IASCC) is a form of intergranular stress corrosion cracking that occurs in irradiated austenitic alloys. It requires an irradiated microstructure along with high temperature water and stress. The process is ubiquitous in that it occurs in a wide range of austenitic alloys and water chemistries, but only when the alloy is irradiated. Despite evidence of this degradation mode that dates back to the 1960s, the mechanism by which it occurs has remained elusive. Here, using high resolution electron backscattering detection to analyze local stress-strain states, high resolution transmission electron microscopy to identify grain boundary phases at crack tips, and decoupling the roles of stress and grain boundary oxidation, we are able to unfold the complexities of the phenomenon to reveal the mechanism by which IASCC occurs. The significance of the findings impacts the mechanical integrity of core components of both current and advanced nuclear reactor designs worldwide. [ABSTRACT FROM AUTHOR]

The continuing rush for potential biomedical applications has sparked the fabrication of graphene quantum dots (GQDs) particularly from agricultural waste. GQDs are unique among carbon-based nanomaterials due to their flexibility, chemical stability, size control, and non-toxic nature. In this study, we have developed Graphene Quantum dots from sugarcane bagasse (GQDs-SB) and sugarcane bagasse pith (GQDs-SBP) by carbonization followed by microwave pyrolysis. The optical properties of the synthesized GQDs-SB and GQDs-SBP were characterized by Ultraviolet–Visible spectroscopy and Photoluminescence (PL) analysis and the surface functional groups were determined by FT- IR analysis. The High resolution transmission electron microscopy (HR-TEM) was used to examine dimensions and structure of GQDs-SB and GQDs-SBP. The storage stability of GQDs-SB and GQDs-SBP was monitored using Ultraviolet–Visible spectroscopy. The synthesized GQDs-SB and GQDs-SBP were evaluated for biological applications like anti-oxidant activity, anti inflammatory activity and cytotoxic effect was also assessed. GQDs-SB and GQDs-SBP demonstrated significant antioxidant and anti-inflammatory effects due to their great ability to scavenge free radicals and extraordinary water solubility. The synthesized GQDs-SB and GQDs-SBP were less toxic in nature. • Synthesizing GQDs from bagasse (GQDs-SB) and pith (GQDs-SBP) offers a transformation from waste to value added products. • Characterization of the synthesized GQDs-SB and GQDs-SBP by different microscopic techniques. • To examine the antioxidant, anti-inflammatory activity and cytotoxic effect of GQDs-SB and GQDs-SBP. [ABSTRACT FROM AUTHOR]

• An expected SnO 2 @CuO/CF heterostructure material is synthesized. • p-n heterojunction enhances the adsorption of H 2 O 2 and benefits sensing properties. • Cost-effective H 2 O 2 electrochemical sensor with excellent performance is obtained. • The developed sensor has good biocompatibility for real-time detection of H 2 O 2 released by living cells. Hydrogen peroxide (H 2 O 2) is a major messenger molecule in cellular signal transduction. It is critical to detect cellular secreted H 2 O 2 in situ for clinical diagnosis and biomedical research. Therefore a simple, fast, sensitive, and cost-effective hydrogen peroxide detection method is needed. In this study, copper foam (CF) was used as copper source and conductive substrate, the electrochemical sensor SnO 2 @CuO/CF is prepared to detect H 2 O 2 secreted by living cells. High resolution transmission electron microscopy (HRTEM), X-ray diffraction, Mott Schottky curves and X-ray photoelectron spectroscopy demonstrate the successful formation of SnO 2 @CuO heterostructure. Theoretical calculations confirm that SnO 2 @CuO heterostructure facilitates the adsorption of H 2 O 2. The designed SnO 2 @CuO/CF sensor shows good sensing performance for H 2 O 2. Under optimal conditions, the designed sensor shows a relatively wide linear range to H 2 O 2 concentration from 1 μM to 13.88 mM, with high sensitivity (5100 μA·mM−1·cm−2) and low detection limit (0.13 μM). Cytotoxicity experiments prove that the sensor has good biocompatibility and the prepared sensor is successfully used to detect H 2 O 2 released by HeLa cells. With superior sensitivity, anti-interference ability, and reproducibility, SnO 2 @CuO /CF shows the potential application of H 2 O 2 monitoring in the field of biomedical and clinical diagnosis. This study provides a new platform for the development of highly sensitive H 2 O 2 electrochemical sensors in practical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

β-Bi 2 O 3 and Ni-incorporated β-Bi 2 O 3 nanoparticles with different Ni incorporating amounts (0, 2, and 4 at. wt. %) were successfully synthesized through a viable hydrothermal process. As-synthesized nanoparticles were analyzed by complementary analytical tools such as X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), UV–visible spectroscopy (UV–Vis), and photoluminescence spectroscopy (PL) for structural, microstructural, compositional, and spectral properties. The photocatalytic performance of synthesized nanoparticles was assessed by subjecting them to visible light irradiation and monitoring the decomposition of rhodamine-B dye. The findings demonstrated that the inclusion of Ni(4%) in β-Bi 2 O 3 nanoparticles significantly enhanced its photocatalytic activity compared to pristine β-Bi 2 O 3 which is desirable for environmental remediation. This improvement may be caused by increased generation of electron-hole (e−-h+) pairs, reduced recombination rate of these pairs, enhanced absorption of visible light, and a decreased band gap energy. To evaluate the specific capacitance characteristics of synthesized electrode materials, cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance analyses were conducted. The super capacitance activities of prepared electrode materials were observed in the order of Bi 2 O 3 < Ni(2%)-Bi 2 O 3 < Ni(4%)-Bi 2 O 3. Notably, Ni(4%)-Bi 2 O 3 nanocomposite exhibited higher supercapacitance, which can be attributed to the effective role of appropriate nickel incorporation in Bi 2 O 3. These results suggested that the incorporation of Ni(4%) into β-Bi 2 O 3 to form a nanocomposite showed greater capability as an effective electrode material for advanced energy storage devices, especially supercapacitors. Ni (0,2,4%) incorporated-Bi 2 O 3 nanoparticles were successfully synthesized and characterized through viable techniques. Ni (4%)- Bi 2 O 3 nanoparticles have shown enhanced visible light driven photocatalytic activity against organic dyes for environmental remediation. It also exhibited high supercapacitance desirable for high capacity electrode material employable in supercapacitors. [Display omitted] • Ag NPs-loaded brookite TiO 2 NWs supported on rGO sheets were produced hydrothermally. • Structure and morphology were evaluated by XRD, XPS and SEM/TEM. • Ag–TiO 2 /rGO nanohybrid exhibited an excellent light induced photocatalytic performance. • A suitable schematic mechanism was proposed for photocatalytic degradation of dye. • Ag–TiO 2 /rGO nanohybrid demonstrated fairly high electrochemical electrode material characteristics. [ABSTRACT FROM AUTHOR]

High manganese steel is influenced by the combined effects of corrosion and wear during service under specific conditions, resulting in components with shortened service life. Under harsh service environments, newly developed Cr+N alloyed austenitic high manganese steel (Mn18Cr7C0.6N0.2 steel) as a new type of railway steel has shown promising results. Herein, the tribocorrosion behaviors of Mn18Cr7C0.6N0.2 and Mn13C1.1 steels in artificial acid rain were studied using electrochemical methods, field emission scanning electron microscope (FE-SEM), focused ion beam scanning electron microscopy (FIB-SEM), scanning transmission electron microscopemicroscopy energy dispersive X-ray spectroscopy (STEM-EDS), and high resolution transmission electron microscopy (HR-TEM). The results showed the formation of passive film and gradient-nanostructure on surfaces of both test steels during tribocorrosion. A dense and tightly adhering amorphous passive film was formed on Mn18Cr7C0.6N0.2 steel surface with a superior blocking effect toward invasive ions. The high strain resistance and plasticity of the Mn18Cr7C0.6N0.2 steel resulted in an intact gradient-nanostructure, suitable for obtaining high surface hardness and maintaining the toughness of the matrix, contribute to providing high wear resistance. The oxide film on the Mn13C1.1 steel surface comprised crystal α-FeOOH. Vortex cracks formed in its gradient structure due to strain localization. Meanwhile, the relatively poor corrosion protection ability and vortex cracks of its gradient-nanostructure prevented it from maintaining interface integrity of the gradient nanostructure, resulting in inferior tribocorrosion resistance. In artificial acid rain, the new type of Cr+N alloyed Mn18Cr7C0.6N0.2 steel exhibited higher tribocorrosion resistance than traditional high manganese steel, promising for use as an excellent wear-resistant material under corrosive environments. • An amorphous passive film formed on the surface of Cr+N alloyed high-Mn steel. • The gradient-nanostructure of Cr+N alloyed high-Mn steel maintained integrity. • Vortex cracks formed in the gradient-nanostructure of traditional high-Mn steel. • Gradient-nanostructure and passive film determined the tribocorrosion resistance. • The surface layer and passive film were fully observed by FIB and TEM. [ABSTRACT FROM AUTHOR]

Pre-stretched strains, 2%, 4%, and 6%, were conducted on the friction-stir-welded dissimilar 2024-to-7075 aluminum alloy joints for strengthening purpose. Tensile tests and microhardness measurements were performed to evaluate the strengthening effect. Transmission electron microscopy and high resolution transmission electron microscopy examinations were employed to characterize precipitates and dislocation structures of the as-welded and pre-stretched joints to elucidate the intrinsic strengthening mechanisms. Results showed that the yield and tensile strengths of the pre-stretched 6% joint respectively increased 147.9 MPa and 31.1 MPa when compared with the as-welded joint. The strain hardening rates of 2024 lower hardness zone (LHZ)-II and 7075 LHZ were higher at the pre-stretched strain rate of 1 mm/min than those of 2 mm/min based on the microhardness area evolution. The yield sequence of the as-welded joint was 2024 LHZ-II, 2024 LHZ-I, 7075 LHZ, stir zone (SZ), and 2024 base material. The appearance of dislocation tangles, dislocation walls, dislocation cells, dislocation pile-ups in the 2024 LHZ-II and 7075 SZ combined with the severe interactions between dislocation structures and precipitates were the dominant strengthening factors. It was very interesting that dislocations provided a diffusion path for Mg atoms and Cu atoms in 2024 LHZ-II during the pre-stretching process. • Pre-stretching was used to strengthen the FSWed dissimilar aluminum alloys joints. • Yield sequence of the FSWed dissimilar aluminum alloys joints was identified. • The strengthened lower hardness zone contributed to the reinforced global joint. • Several kinds of dislocations structures induced by the pre-stretching process. • Dislocations provided a diffusion path for Mg and Cu atoms in 2024 aluminum alloy. [ABSTRACT FROM AUTHOR]

Owing to the combination of good thermo-optical properties and inhomogeneously broadened fluorescence spectra suitable for ultrashort laser pulse generation, rare-earth doped solid solutions of sesquioxides (Y,Lu,Sc) 2 O 3 have attracted considerable interest in recent years. In this study, compositionally disordered Tm3+-doped YScO 3 transparent ceramic was fabricated using solid-state vacuum sintering of nanopowder produced using laser ablation of solid target in air flow. The as-synthesized powder consisted of weakly aggregated spherical particles having 20 nm diameter and a mostly monoclinic (space group C 2/ m) crystal structure, whose symmetry was transformed into cubic (space group Ia -3) by calcination at 1050 °C. From high resolution transmission electron microscopy (HRTEM) and energy dispersive X-ray analysis (EDX), we observed a homogeneous distribution of components both throughout individual nanoparticles and 100-nm-thick ceramic foil resulting in high structural and optical quality of the obtained samples. The sintered ceramic featured an optical transmission of 77% at 600 nm and above 81% near 2 μm, an average grain size of 24.2 μm and a content of scattering centers of 26.1 ppm. The absorption spectra at several temperatures, from 93 K to 293 K, were measured and the corresponding absorption coefficients were obtained by Lambert-Beer formula in the range from 600 nm to 900 nm and from 1400 nm to 2100 nm. In particular, the room temperature absorption cross section at 794 nm and 1634 nm were determined to be σ abs = 4.25 × 10−21 cm2 and σ abs = 5.01 × 10−21 cm2 respectively. Concerning the emission cross section it was calculated by Fuchtbauer-Ladenburg equation starting from the fluorescence spectrum acquired at the laser work temperature: at 1951 nm and 2106 nm corresponding to the main two emission peaks belonging the curve, it was found σ em = 9.2 × 10−21 cm2 and σ em = 4.9 × 10−21 cm2, respectively. Finally, it was tested the laser behavior of the ceramic: pumped at 793 nm in quasi -CW mode it delivered 1.27 W of output power with a slope efficiency of 10.33% at 2081 nm. The tunability curve spans from 1942 nm to 2110 nm (i. e. 168 nm). • Tm 0.05 (Y 0.5 Sc 0.5) 1.95 O 3 laser ceramic. • Solid-state vacuum sintering from laser-ablated (Tm,Y,Sc) 2 O 3 nanoparticles. • Tm-based laser with emission peak at 2081 nm. • Broad laser wavelength tuning range (from 1942 nm to 2110 nm). [ABSTRACT FROM AUTHOR]

[Display omitted] • SnS and SnS 2 are synthesized in the form of quantum dots from aqueous solutions. • Syntheses are conducted under room conditions thanks to application of ultrasound. • Influence of sonication time on QDs properties is investigated. • SnS and SnS 2 QDs were utilized as photo- and (for the first time) sonocatalysts. • The greatest color removal was observed in the case of SnS QDs sonocatalyst (85.2%) Our study reports the ultrasound-assisted synthesis of SnS and SnS 2 in the form of nanoparticles using aqueous solutions of respective tin chloride and thioacetamide varying sonication time. The presence of both compounds is confirmed by powder X-ray diffraction, energy-dispersive X-ray spectroscopy, as well as Raman and FT-IR spectroscopic techniques. The existence of nanoparticles is proven by powder X-ray diffraction investigation and by high resolution transmission electron microscopy observations. The size of nanocrystallites are in the range of 3–8 nm and 30 50 nm for SnS, and 1.5–10 nm for SnS 2. X-ray photoelectron spectroscopy measurements, used to investigate the chemical state of tin and sulphur atoms on the surface of nanoparticles, reveal that they are typically covered with tin on the same oxidation degree as respective bulk compound. Values of optical bandgaps of synthesized nanoparticles, according to the Tauc method, were 2.31, 1.47 and 1.05 eV for SnS (60, 90 and 120 min long synthesis, respectively), and 2.81, 2.78 and 2.70 eV for SnS 2 (60, 90 and 120 min long synthesis, respectively). Obtained nanoparticles were utilized as photo- and sonocatalysts in the process of degradation of model azo-dye molecules by UV-C light or ultrasound. Quantum dots of SnS 2 obtained under sonication lasting 120 min were the best photocatalyst (66.9 % color removal), while quantum dots of SnS obtained under similar sonication time were the best sonocatalyst (85.2 % color removal). [ABSTRACT FROM AUTHOR]

This paper presents the recrystallization of sodium bicarbonate (NaHCO 3) using the Supercritical AntiSolvent process. The focus is pointed toward crystal habit and its modification induced by varying the solvent nature. The observed habit is uncommon with crystals exhibiting a "zigzag" shape. High Resolution Scanning Electron Microscopy observations refuted that this shape was due to particle attachment: those "zigzag" particles are likely monocrystals grown in a diffusion-limited media. Firstly, a molecular modeling study shed light on organic solvents that can interact strongly with NaHCO 3 crystals. Such solvents were found to be ethylene glycol and glycine, in contrast to ethanol or water which likely interact weakly with NaHCO 3 crystals. An experimental campaign confirmed the predicted interactions. Ethylene glycol interactions with NaHCO 3 crystals led to the production of a different crystal salt. Alternatively, adding glycine as a growth inhibitor led to the initial polymorphic form, although with a modified growth mechanism. [Display omitted] • Sodium bicarbonate (NaHCO 3) recrystallized using the supercritical anti-solvent process. • Atypical "Zigzag" crystals formed, caused by an alternating growth direction. • Molecular modeling shows NaHCO 3 crystal interactions with Ethylene Glycol and Glycine. • Selective interactions of Ethylene Glycol with NaHCO 3 crystals allow for polymorphism control. • Strong Interactions of Glycine with NaHCO 3 crystals hinder the nucleation and growth. [ABSTRACT FROM AUTHOR]

[Display omitted] • The surface chemical composition of β-Ga 2 O 3 films is discussed in depth. • The component of O 1s with the binding energy around 531.8 eV is attributed to surface lattice O atoms. • The defects inside the β-Ga 2 O 3 films were analyzed by HRTEM. β gallium oxide (β-Ga 2 O 3) is an ultrawide bandgap semiconductor with great potential for solar-blind ultraviolet detection, power devices, and gas sensing. However, the understanding of the surface properties of β-Ga 2 O 3 remains insufficient. Here, epitaxial growth of β-Ga 2 O 3 films was carried by metal–organic chemical vapor deposition (MOCVD) on sapphire substrates. The surface chemical composition, surface layer crystalline properties, and surface morphology of the β-Ga 2 O 3 films were discussed and analyzed in detail. By comparing the atomic ratios of O/Ga, the surface morphology, and the crystalline properties of the films, we attribute the component of O 1s with the binding energy around 531.8 eV to surface lattice O atoms. Moreover, the one-dimensional defects inside the surface layers and the near-interface regions of the films were observed at atomic scale by high resolution transmission electron microscopy (HRTEM). By comparing the lattice fringes of different facets, the geometric phase uniformity, and the distribution of strain, we found that the crystalline quality of the surface layers is much higher than the near-interface regions. [ABSTRACT FROM AUTHOR]