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Clavibacter michiganensis subsp. michiganensis (Cmm) and C. michiganensis subsp. capsici (Cmc) are phytopathogenic bacteria that cause bacterial canker disease in tomatoes and peppers, respectively. Bacterial canker disease poses serious challenges to solanaceous crops, causing significant yield losses and economic costs. Effective management necessitates the development of sustainable control strategies employing nanobiotechnology. In this study, the antibacterial effects of four Aspergillus sojae -mediated nanoformulations, including cobalt oxide nanoparticles (Co 3 O 4 NPs), zinc oxide nanoparticles (ZnO NPs), cobalt ferrite nanoparticles (CoFe 2 O 4 NPs), and CoFe 2 O 4 /functionalized multi-walled carbon nanotube (fMWCNT) bionanocomposite, were evaluated against Cmm and Cmc. The diameters of the zone of inhibition of A. sojae -mediated Co 3 O 4 NPs, ZnO NPs, CoFe 2 O 4 NPs, and CoFe 2 O 4 /fMWCNT bionanocomposite against Cmm and Cmc were 23.60 mm, 22.09 mm, 27.65 mm, 22.51 mm, and 19.33 mm, 17.66 mm, 21.64 mm, 18.77 mm, respectively. The broth microdilution assay was conducted to determine the minimal inhibitory and bactericidal concentrations. The MICs of Co 3 O 4 NPs, ZnO NPs, CoFe 2 O 4 NPs, and CoFe 2 O 4 /fMWCNT bionanocomposite against Cmm were 2.50 mg/mL, 1.25 mg/mL, 2.50 mg/mL, and 2.50 mg/mL, respectively. While, their respective MBCs against Cmm were 5.00 mg/mL, 2.50 mg/mL, 5.00 mg/mL, and 5.00 mg/mL. The respective MICs of Co 3 O 4 NPs, ZnO NPs, CoFe 2 O 4 NPs, and CoFe 2 O 4 /fMWCNT bionanocomposite against Cmc were 2.50 mg/mL, 1.25 mg/mL, 5.00 mg/mL, and 5.00 mg/mL. While, their respective MBCs against Cmc were 5.00 mg/mL, 2.50 mg/mL, 10.00 mg/mL, and 10.00 mg/mL. The morphological and ultrastructural changes of Cmm and Cmc cells were observed using field-emission scanning and transmission electron microscopy before and after treatment with sub-minimal inhibitory concentrations of the nanoformulations. Nanoformulation-treated bacterial cells became deformed and disrupted, displaying pits, deep cavities, and groove-like structures. The cell membrane detached from the bacterial cell wall, electron-dense particles accumulated in the cytoplasm, cellular components disintegrated, and the cells were lysed. Direct physical interactions between the prepared nanoformulations with Cmm and Cmc cells might be the major mechanism for their antibacterial potency. Further research is required for the in vivo application of the mycosynthesized nanoformulations as countermeasures to combat bacterial phytopathogens. [Display omitted] • A. sojae -mediated nanoformulations exhibited significant antibacterial potential against phytopathogens. • Assessment of morphological and ultrastructural changes using FESEM and TEM. • Elucidation of plausible antibacterial mechanism of A. sojae -mediated nanoformulations. • Mycosynthesis of nanoformulations is a green approach for plant disease management. [ABSTRACT FROM AUTHOR]

In general, defects are crucial in designing the different properties of two-dimensional materials. Therefore large variations in the electric and optical characteristics of two-dimensional layered molybdenum disulphide might be attributed to defects. This study presents the design of a temperature and nitrogen sensor based on few-layer molybdenum disulfide sheets (FLMS), which was developed from bulk MoS2 (BMS) through an exfoliation approach. The produced sulfur defect, molybdenum defect, line defect, and plane defect were characterized by scanning transmission electron microscopy (STEM), which substantially impacts the sensing characteristics of the resulting FLMS. Our theoretical analysis validates that the sulfur vacancies of the MoS2 lattice improve sensing performance by promoting effective charge transfer and surface interactions with target analytes. The FLMS-based sensor showed a high sensitivity for detecting nitrogen gas with a detection limit (LOD) of ~ 0.18 ppm. Additionally, temperature-detecting capabilities were assessed over various temperatures, showing outstanding stability and repeatability. To the best of our knowledge, this material is the first of its kind, demonstrating visible N2 gas sensing with chromic behaviour. [ABSTRACT FROM AUTHOR]

Bimetallic PtRu/C catalysts have been prepared by depositing Ru onto a commercial Pt/C catalyst and subsequent thermal annealing. Different Pt : Ru ratios of 1 : 1, 2 : 1, 4 : 1, 8 : 1, and 16 : 1 have been investigated with annealing temperatures of 350 and 500 °C. Using X‐ray diffraction (XRD), synchrotron powder X‐ray diffraction (SPXRD) combined with pair distribution function (PDF) analysis and scanning transmission electron microscopy with energy dispersive X‐ray spectrum imaging (STEM‐EDXS), we show that diffusion of Ru into the fcc crystal structure of the Pt nanoparticles takes place during thermal annealing. Partial segregation and the formation of Pt nanoclusters on the bimetallic surface was observed depending on the Pt : Ru ratio. The annealing process does not only cause a high Pt dispersion but also affects the electronic structure of the Pt surface by broadening the d‐band thus facilitating the product's desorption from the surface of the bimetallic particle. These beneficial effects have been exemplified for the catalytic dehydrogenation of dicyclohexylmethanol, a promising hydrogen carrier compound with 7.2 wt% hydrogen capacity. The most active catalyst material among the tested supported alloys and monometallic reference materials was Pt4Ru1/C after annealing at 500 °C, which increased the hydrogen release productivity by 65 % compared to the unmodified Pt/C catalyst. [ABSTRACT FROM AUTHOR]

Dry reforming of methane (DRM) is an attractive reaction for synthesis gas production, since it converts two greenhouse gases into valuable chemical feedstock. Silica supported bimetallic catalysts with constant metal loading but varying Ni/Co ratios (xNi=1, 0.8, 0.6, 0.5, 0.4, 0.2, 0) were produced via spray‐drying for the application in DRM, aiming at the identification of compositions with superior activity. In this study, building block particles refer to an inert framework, supporting the catalyst. The elemental distribution of Si, Ni, and Co within such building block particles was evaluated using scanning transmission electron microscopy. Additionally, X‐ray diffraction and temperature‐programmed reduction experiments confirmed that Ni and Co initially exist in an oxidic state within the SiO2 framework after production and later transform into an alloyed metallic state upon reduction with hydrogen, as confirmed by X‐ray photoelectron spectroscopy. A systematic comparison of the activity over a temperature range (323–1150 K) was performed using temperature scanning measurements. The highest intrinsic activity was found with the bimetallic Ni40Co60 particles. [ABSTRACT FROM AUTHOR]

Atomic‐resolution scanning transmission electron microscopy (STEM) characterization requires precise tilting of the specimen to a high symmetric zone axis, which is usually processed in reciprocal space by following the diffraction patterns. However, for small‐sized nanocrystalline materials, their diffraction patterns are often too faint to guide the tilting process. Here, a simple and effective tilting method is developed based on the diffraction contrast change of the shadow image in the Ronchigram. The misorientation angle of the specimen can be calculated and tilted to the zone axis based on the position of the shadow image with lowest intensity. This method requires no prior knowledge of the sample and the maximum misorientation angle that can be corrected is >±6.9° with sub‐mrad accuracy. It operates in real space, without recording the diffraction patterns of the specimens, making it particularly effective for nanocrystalline materials. Combined with the scripting to control the microscope, the sample can be automatically tilted to the zone axis under low dose conditions (<0.17 e− Å−2 s−1), facilitating the imaging of beam sensitive materials such as zeolites or metal‐organic frameworks. This automated tilting method can significantly contribute to the atomic‐scale characterization of the nanocrystalline materials by STEM imaging. [ABSTRACT FROM AUTHOR]

The green synthesis of nanoparticles using lichen extracts offers a safer and more environmentally friendly alternative to traditional methods. Known for their medicinal properties, lichens can effectively reduce and stabilise metallic salts, providing an eco-friendly approach to producing nanomaterials with potential antimicrobial applications. In this study, the lichen Rhizoplaca chrysoleuca was utilised in the green synthesis of nanoparticles, successfully creating lichen-derived silver-zinc oxide (Ag–ZnO), silver-strontium oxide (Ag–SrO), and silver-nickel oxide (Ag–NiO) nanoparticles. Ultraviolet–visible absorption spectroscopy revealed that the characteristic light absorption of the NCs occurred within the range of 300–400 nm for each synthesis, and dynamic light scattering measurements indicated that the hydrodynamic diameters of the nanoparticles were below 100 nm. Energy-dispersive X-ray spectroscopy confirmed the presence of the constituent elements. Imaging with field-emission scanning electron microscopy and scanning transmission electron microscopy showed that the nanoparticles had spherical shapes with dimensions measuring below 50 nm. X-ray diffraction analysis of the synthesised nanocomposite materials revealed the presence of Ag–ZnO (22 nm), Ag–SrO (48 nm), and Ag–NiO (21 nm) nanoparticles. Fourier-transform infrared spectroscopy identified functional groups in the nanoparticles, confirming their compositions, while thermogravimetric analysis determined the thermal decomposition temperatures of the NCs. The antibacterial efficacy of these materials was assessed, with Ag–ZnO (inhibition zone 11.0 mm) and Ag–NiO (inhibition zone 10.0 mm) showing significant effectiveness against both Gram-negative and Gram-positive bacteria. In contrast, Ag–SrO (inhibition zone 6.5 mm) exhibited comparatively lower antibacterial activity. Additionally, the study highlighted the antifungal properties of Ag–NiO (inhibition zone 19.0 mm) and Ag–ZnO (inhibition zone 8.5 mm) nanomaterials. This research advances the understanding of lichen-based nanotechnology and its potential for developing sustainable antimicrobial solutions. [Display omitted] [ABSTRACT FROM AUTHOR]

2D van der Waals (vdW) magnets provide the ideal platform for studying magnetism at low dimensions, where the magnetic properties can be further tuned by intercalating magnetic species and manipulating their stoichiometry and local atomic configuration. However, achieving stoichiometric intercalated 2D magnets necessitates precise control of growth parameters to avoid local compositional variations, which fosters phase coexistence that significantly impacts magnetic properties. Here a comprehensive scanning transmission electron microscopy (STEM) examination of the structural evolution in chemical vapor deposition (CVD)‐grown self‐intercalated V1+xSe2 nanoplates is shown, exploring their response to annealing temperature variations and the subsequent influence on magnetic properties. By combining ex situ and in situ post‐growth annealing, the rearrangement of intercalants is directly observed at the interlayer and identify a structural phase transition of the nanodomains embedded in the VSe2 matrix from V3Se4 to a V5Se8 structure occurring at ≈250 °C. The interlayer reconstruction is manifested by a positive‐to‐negative cross‐over in the magnetoresistance and an upturn in resistivity at low temperatures. The results provide new ways for tailoring 2D vdW magnets through post‐growth thermal annealing. [ABSTRACT FROM AUTHOR]

Rapid connectivity homogenization and ultra-probe sonication were used to manufacture the Azelic acid nanoemulsion. Everything is dissolved in clean water: Azelic acid, polyvinyl alcohol, xanthan gum, castor oil, vitamin E, Transcutol P, and Tween 80. To optimize it, we used Response Surface Methodology and measured a bunch of parameters, like droplet size (nm), surface morphology (FE-SEM, TEM), zeta potential (ZP), differential scanning calorimetry (DSC), polydispersity index (PDI), stability, pH, and viscosity. Both the penetration and retention of the Azelic acid -loaded nanoemulsion into the skin and its release profile were studied in vitro and ex vivo, respectively. The model's quadratic polynomial fitness was confirmed by the optimization analysis of variance (ANOVA), which yielded a significant F-value and a p-value below 0.0500. It was also determined that the lack-of-fit was not statistically significant. Globule size was 200 nm, PDI was 0.2, and entrapment efficacy was 84.99% following optimization of the Azelic acid nanoemulsion. A value of - 35.90 mV was recorded for the Zeta Potential (ZP). The absence of chemical interactions was verified by the findings of FTIR, DSC, and XRD investigations, which demonstrated the effective trapping of Azelic acid. Results from scanning electron microscopy and transmission electron microscopy revealed the presence of small spherical particles in the enhanced formulation. Centrifugation, freezethaw cycles, and storage at 5°C and 25°C were all successfully completed by the sample in the stability tests. Storage at 40°C for 7 weeks resulted in subtle color shifts, most noticeably during the last week of the study. The results of the rheological tests showed that the revised recipe is elastic and May shear-thin and pseudo-plastic. Over the course of 12 hours, the Azelic acid nanoemulsion released 87.66 % and 97.99 of its active ingredient. A high degree of linearity was demonstrated by the sustained release pattern, which matched a zero-order kinetic model (R2 = 0. 0.9952). After 8 hours, the Azelic acid nanoemulsion had an ex vivo penetration rate of 82.24 %, indicating better skin distribution. Based on the results, Azelic acid nanoemulsion might be useful as a skin condition topical therapy. Nevertheless, further research, including studies conducted in living organisms, is necessary to prove that azelic acid nanoemulsion is both efficient and safe. [ABSTRACT FROM AUTHOR]

The microstructure of alloys of the Cu – Cr – Zr system after equal channel angular pressing and aging is investigated by scanning and transmission electron microscopy. Mechanical properties and electrical conductivity are determined. Recovery and additional precipitation of dispersed particles are observed in deformed alloys after annealing at temperatures of 200 – 500°C, but static recrystallization does not develop. Increasing the annealing temperature to 600°C is accompanied by development of recrystallization, and a completely recrystallized structure is observed within the alloy with a minimum content of alloying elements, while deformed areas are found in alloys with a high content of chromium and zirconium. The influence of structural evolution on mechanical properties and electrical conductivity is discussed. [ABSTRACT FROM AUTHOR]

The VZhM4 single-crystal Ni-based superalloy was tested for high-temperature salt-induced corrosion resistance in Na2SO4 + NaCl at 750°C. The equilibrium composition of phases formed during the interaction of the alloy with oxygen and sulfur across the temperature range of 600 – 1000°C were calculated. Changes in the structure and composition of the surface layer of the alloy during high-temperature salt corrosion were studied using scanning and transmission electron microscopy. The results obtained were used to compile structural diagrams for the corrosion layer formed on the alloy after 5 and 20 test cycles. The quantitative composition of the main phases in the corrosion products was determined. A qualitative assessment of Re, Ta, and Ru diffusion was performed. [ABSTRACT FROM AUTHOR]

Aberration‐corrected scanning transmission electron microscopy (STEM) has been advancing resolution, sensitivity, and microanalysis due to the intense demands of atomic‐level microstructural investigations. Recent STEM technologies require preparing a thin lamella whose thickness is ideally below 20 nm. Although focused‐ion‐beam/scanning‐electron‐microscopy (FIB/SEM) is an established method to prepare a high‐quality lamella, nanometer‐level controllability of lamella thickness remains a fundamental problem. Here, the robust preparation of a sub‐20‐nm‐thin lamella is demonstrated by FIB/SEM with real‐time feedback from thickness quantification. The lamella thickness is quantified by back‐scattered‐electron SEM imaging in a thickness range between 0 and 100 nm without any reference to numerical simulation. Using real‐time feedback from the thickness quantification, the FIB/SEM terminates thinning a lamella at a targeted thickness. The real‐time feedback system eventually provides 1‐nm‐level controllability of the lamella thickness. As a proof‐of‐concept, a near‐10‐nm‐thin lamella is prepared from a SrTiO3 crystal by our methodology. Moreover, the lamella thickness is controllable at a target heterointerface. Thus, a sub‐20‐nm‐thin lamella is prepared from a LaAlO3/SrTiO3 heterointerface. The methodology offers a robust and operator‐independent platform to prepare a sub‐20‐nm‐thin lamella from various materials. This platform will broadly impact aberration‐corrected STEM studies in materials science and the semiconductor industry. [ABSTRACT FROM AUTHOR]

This article discusses the importance of phase engineering in nanomaterials and highlights the progress that has been made in this field. The authors focus on noble metals and transition-metal dichalcogenides (TMDs) as examples of nanomaterials that can be engineered to have unconventional crystal phases, amorphous phases, and heterophases. They describe various strategies for phase engineering, including direct-synthesis and phase-transformation methods. The article also addresses the challenges and future research directions in this emerging field. Overall, this article provides valuable insights into the phase engineering of nanomaterials and its potential applications. [Extracted from the article]

This document provides summaries of the winners of the 15th Microscopy Today Innovation Awards competition. The winners include CrystalView Microscope, Volutome, CICERO, Lightning Arctic, and Tempo. These innovations improve polarization accuracy, provide 3D imaging, make high-end imaging accessible, offer cooling and heating capabilities, and minimize electron dose while equalizing the signal-to-noise ratio. The document also highlights five other technological innovations, including LightSpeed Mode, AEcroscopy, Unity, HexAuFoil cryoEM specimen supports, and the Thermo Scientific Meridian EX Fault Isolation System. These innovations have applications in various scientific fields and offer improvements in imaging speed, data quality, and defect analysis. [Extracted from the article]

Herein, high‐resistivity silicon substrates with specific He+ ion implantations to mitigate the parasitic surface conduction effect are studied. Several postimplantation thermal annealing conditions are investigated. Substrate performance is assessed at radiofrequencies (RFs) using the small‐signal characterization of coplanar waveguides (CPW) structures. The best effective resistivity (ρeff) of 4 kΩ cm is achieved with the wafer annealed at 600 °C for 2 h. This ρeff value is also stable as a function of DC bias applied to the CPWs. Those high RF performances originate from the nature of the defects created by ion implantation. Defects are deeply analyzed using spectroscopy measurement and scanning transmission electron microscopy. Combining these measurements, it is shown that {311} defects are probably responsible for the achieved high RF performances. Finally, the link between charge carriers trapping in the RF domain and defects nature is discussed to develop a defects engineering strategy for low‐loss RF substrates. The proposed fabrication method enables the fabrication of RF passivation layer locally over the wafer, and thus the cointegration of RF devices with fully depleted silicon‐on‐insulator technology. [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to purify proanthocyanidins from areca nut seeds (P-AN) and to investigate the bactericidal activity and mechanism of the purified products against Streptococcus mutans. Methods and results Ultra-performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry, Fourier transform infrared, Matrix-assisted laser desorption/ ionization time of flight mass spectrometry (MADLI-TOF-MS), and thiolysis experiment were used for P-AN chemical analysis. Time-kill analysis and glycolytic pH drop were used to evaluate the activity of S. mutans in vitro. Meanwhile, the investigation of the bacteriostatic mechanism included membrane protein, fluidity, permeability, and integrity tests. The results showed that P-AN was a kind of proanthocyanidin mainly composed of B-type proanthocyanidins and their polymers. Moreover, MADLI-TOF-MS and thiolysis experiments demonstrated that the degree of polymerization of P-AN was 13. The time-kill analysis showed that P-AN had strong bactericidal activity against S. mutans. P-AN at minimum inhibitory concentration (MIC) concentrations was able to induce S. mutans death, while complete lethality occurred at 2 MIC. Glycolysis test showed that P-AN significantly inhibited S. mutans acid production (P  < .01). The morphological changes of S. mutans were observed by scanning electron microscopy and transmission electron microscopy experiments, which indicated that P-AN destroyed the cellular structure of S. mutans. At the same time, significant changes were observed in membrane proteins, fluidity, permeability, and integrity. Conclusion P-AN can effectively inhibit the activity of S. mutans. P-AN can reduce the erosion of the tooth surface by the acid of S. mutans. P-AN could break the structure of the cell membrane protein of S. mutans. P-AN could destroy the integrity of membrane, resulting in the death of S. mutans. [ABSTRACT FROM AUTHOR]

The process of stone formation in the human body remains incompletely understood, which requires clinical and laboratory studies and the formulation of a new endogenous, nanotechnological concept of the mechanism of origin and formation of crystallization centers. Previously, the mechanism of sialolithiasis was considered a congenital disease associated with the pathology of the ducts in the structure of the glands themselves. To date, such morphological changes of congenital nature can be considered from the position of the intrauterine formation of endogenous bacterial infections complicated by the migration of antigenic structures initiating the formation of crystallization centers. The present work is devoted to the study of the morphology and composition of stones obtained as a result of surgical interventions for sialolithiasis. Presumably, nanoparticles of metals and other chemical compounds can be structural components of crystallization centers or incorporated into the conditions of chronic endogenous inflammation and the composition of antigenic structures, in complexes with protein and bacterial components. X-ray microtomography, X-ray fluorescence analysis, scanning transmission electron microscopy and microanalysis, mass spectrometry, and Raman spectroscopy were used to study the pathogenesis of stone formation. Immunoglobulins (Igs) of classes A and G, as well as nanoparticles of metals Pb, Fe, Cr, and Mo, were found in the internal structure of the stones. The complex of antigenic structures was an ovoid calcified layered matrix of polyvid microbial biofilms, with the inclusion of metal nanoparticles and chemical elements, as well as immunoglobulins. The obtained results of clinical and laboratory studies allow us to broaden the view on the pathogenesis of stone formation and suggest that the occurrence of the calcification of antigenic structures may be associated with the formation of IgG4-associated disease. [ABSTRACT FROM AUTHOR]

Personal protective equipment (PPE) has attracted more attention since the outbreak of the epidemic in 2019. Advanced nano techniques, such as electrospinning, can provide new routes for developing novel PPE. However, electrospun antibacterial PPE is not easily obtained. Fibers loaded with photosensitizers prepared using single-fluid electrospinning have a relatively low utilization rate due to the influence of embedding and their inadequate mechanical properties. For this study, monolithic nanofibers and core–shell nanofibers were prepared and compared. Monolithic F1 fibers comprising polyethylene oxide (PEO), poly(vinyl alcohol-co-ethylene) (PVA-co-PE), and the photo-antibacterial agent vitamin K3 (VK3) were created using a single-fluid blending process. Core–shell F2 nanofibers were prepared using coaxial electrospinning, in which the extensible material PEO was set as the core section, and a composite consisting of PEO, PVA-co-PE, and VK3 was set as the shell section. Both F1 and F2 fibers with the designed structural properties had an average diameter of approximately 1.0 μm, as determined using scanning electron microscopy and transmission electron microscopy. VK3 was amorphously dispersed within the polymeric matrices of F1 and F2 fibers in a compatible manner, as revealed using X-ray diffraction and Fourier transform infrared spectroscopy. Monolithic F1 fibers had a higher tensile strength of 2.917 ± 0.091 MPa, whereas the core–shell F2 fibers had a longer elongation with a break rate of 194.567 ± 0.091%. Photoreaction tests showed that, with their adjustment, core–shell F2 nanofibers could produce 0.222 μmol/L ·OH upon illumination. F2 fibers had slightly better antibacterial performance than F1 fibers, with inhibition zones of 1.361 ± 0.012 cm and 1.296 ± 0.022 cm for E. coli and S. aureus, respectively, but with less VK3. The intentional tailoring of the components and compositions of the core–shell nanostructures can improve the process–structure–performance relationship of electrospun nanofibers for potential sunlight-activated antibacterial PPE. [ABSTRACT FROM AUTHOR]

Solketal, a widely used glycerol-derived solvent, can be efficiently synthesized through heterogeneous catalysis, thus avoiding the significant product losses typically encountered with aqueous work-up in homogeneous catalysis. This study explores the catalytic synthesis of solketal using solid acid catalysts derived from recovered carbon blacks (rCBs), which are obtained through the pyrolysis of end-of-life tires. This was further converted into solid acid catalysts through the introduction of acidic functional groups using concentrated H2SO4 or 4-benzenediazonium sulfonate (BDS) as sulfonating agents. Additionally, post-pyrolytic rCB treated with glucose and subsequently sulfonated with sulfuric acid was also prepared. Comprehensive characterization of the initial and modified rCBs was performed using techniques such as elemental analysis, powder X-ray diffraction, thermogravimetric analysis, a back titration method, and both scanning and transmission electron microscopy, along with X-ray photoelectron spectroscopy. The catalytic performance of these samples was evaluated through the batch mode glycerol acetalization to produce solketal. The modified rCBs exhibited substantial catalytic activity, achieving high glycerol conversions (approximately 90%) and high solketal selectivity (around 95%) within 30 min at 40 °C. This notable activity was attributed to the presence of -SO3H groups on the surface of the functionalized rCBs. Reusability tests indicated that only rCBs modified with glucose demonstrated acceptable catalytic stability in subsequent acetalization cycles. The findings underscore the potential of utilizing end-of-life tires to produce effective acid catalysts for glycerol valorization processes. [ABSTRACT FROM AUTHOR]

A nanostructured material, ordered mesoporous carbon (OMC), was synthesised in metal- and halide-free form and its use for the sequestration of crystal violet, a hazardous triphenylmethane dye, is reported for the first time. The OMC material is characterised using scanning transmission electron microscopy with energy-dispersive spectroscopy for chemical analysis, by Fourier-transform infrared spectroscopy, and by nitrogen gas physisorption. The ideal conditions for the uptake of crystal violet dye were determined in batch experiments covering the standard parameters: pH, concentration, contact time, and adsorbent dosage. Experimental data are validated by applying Langmuir, Freundlich, Dubinin–Radushkevich, and Temkin isotherms. The thermodynamic parameters, ΔH°, ΔG°, and ΔS°, are calculated and it has been found that the adsorption process is spontaneous and endothermic with increasing disorder. An in-depth analysis of the kinetics of the adsorption process, order of the reaction and corresponding values of the rate constants was performed. The adsorption of crystal violet over OMC has been found to follow pseudo-second-order kinetics through a film diffusion process at all temperatures studied. Continuous flow column operations were performed using fixed bed adsorption. Parameters including percentage saturation of the OMC bed are evaluated. The exhausted column was regenerated through a desorption process and column efficiency was determined. [ABSTRACT FROM AUTHOR]

The adsorption properties of microporous carbon materials modified with iron citrate were investigated. The carbon materials were produced based on resorcinol-formaldehyde resin, treated in a microwave assisted solvothermal reactor, and next carbonized in the tube furnace at a temperature of 700 °C under argon atmosphere. Iron citrate was applied as a modifier, added to the material precursor before the synthesis in the reactor, in the quantity enabling to obtain the nanocomposites with C:Fe mass ratio equal to 10:1. Some samples were additionally activated using potassium oxalate or potassium hydroxide. The phase composition of the produced nanocomposites was determined using the X-ray diffraction method. Scanning and transmission electron microscopy was applied to characterize the changes in samples' morphology resulting from the activation process and/or the introduction of iron into the carbon matrix. The adsorption of nitrogen from gas phase and dyes (methylene blue and congo red) from water solution on the obtained materials was investigated. In the case of methylene blue, the adsorption equilibrium isotherms followed the Langmuir isotherm model. However, in the case of congo red, a linear dependency of adsorption and concentration in a broad equilibrium concentration range was found and well-described using the Henry equation. The most efficient adsorption of methylene blue was noticed for the sample activated with potassium hydroxide and modified with iron citrate, and a maximum adsorption capacity of 696 mg/g was achieved. The highest congo red adsorption was noticed for the non-activated sample modified with iron citrate, and the partition coefficient for this material equaled 171 dm3/g. [ABSTRACT FROM AUTHOR]

Persistent homology is a powerful tool for quantifying various structures, but it is equally crucial to maintain its interpretability. In this study, we extracted interpretable geometric features from the persistent diagrams (PDs) of scanning transmission electron microscopy (STEM) images of self-assembled Pt-CeO2 nanostructures synthesized under different annealing conditions. We focused on PD quadrants and extracted five interpretable features from the zeroth and first PDs of nanostructures ranging from maze-like to striped patterns. A combination of hierarchical clustering and inverse analysis of PDs reconstructed by principal component analysis through vectorization of the PDs highlighted the importance of the number of arc-like structures of the CeO2 phase in the first PDs, particularly those that were smaller than a characteristic size. This descriptor enabled us to quantify the degree of disorder, namely the density of bends, in nanostructures formed under different conditions. By using this descriptor along with the width of the CeO2 phase, we classified 12 Pt-CeO2 nanostructures in an interpretable way. [ABSTRACT FROM AUTHOR]

Effective solid-phase extractants (SPE) based on multi-walled carbon nanotubes (CNT) of various structures modified with an organic reagent, 2-mercaptobenzothiazole, were developed. Using scanning and transmission electron microscopy, the morphological and structural features of SPE samples and their elemental composition were determined. It was shown that the specific surface area of the modified CNT is approximately two times lower compared to the original CNT. It was revealed that the modified materials are CNT coils coated with a uniform organic shell 10−15 nm thick. The sorption capacity of the original nanotubes in 1.0 M HCl and of their modified forms (in 0.1−3.0 M HCl) at room temperature and at 80°C was determined. It was found out that in strongly acidic media, SPE based on G-183 CNT and 2-mercaptobenzothiazole, effectively sorbs Pt, Pd and Au at room temperature, and Ru and Rh at the temperature of 80°C. A possibility of the selective extraction of platinum group metals and gold with this sorbent in the presence of macroquantities of Al, Fe, Cu, Ca and Mg was assessed. [ABSTRACT FROM AUTHOR]

In situ and operando investigation of photocatalysts plays a fundamental role in understanding the processes of active phase formation and the mechanisms of catalytic reactions, which is crucial for the rational design of more efficient materials. Using a custom‐made operando photocatalytic cell, an in situ procedure to follow the formation steps of Pd/TiO2 photocatalyst by synchrotron‐based X‐ray absorption spectroscopy (XAS) is proposed. The procedure resulted in the formation of ∼1 nm Pd particles with a much narrower size distribution and homogeneous spreading over TiO2 support compared with the samples generated in a conventional batch reactor. The combination of in situ XAS spectroscopy with high‐angle annular dark‐field scanning transmission electron microscopy demonstrated the formation of single‐atom Pd(0) sites on TiO2 as the initial step of the photodeposition process. Palladium hydride particles were observed for all investigated samples upon exposure to formic acid solutions. [ABSTRACT FROM AUTHOR]

Here we show that compressive sensing allows 4‐dimensional (4‐D) STEM data to be obtained and accurately reconstructed with both high‐speed and reduced electron fluence. The methodology needed to achieve these results compared to conventional 4‐D approaches requires only that a random subset of probe locations is acquired from the typical regular scanning grid, which immediately generates both higher speed and the lower fluence experimentally. We also consider downsampling of the detector, showing that oversampling is inherent within convergent beam electron diffraction (CBED) patterns and that detector downsampling does not reduce precision but allows faster experimental data acquisition. Analysis of an experimental atomic resolution yttrium silicide dataset shows that it is possible to recover over 25 dB peak signal‐to‐noise ratio in the recovered phase using 0.3% of the total data. Lay abstract: Four‐dimensional scanning transmission electron microscopy (4‐D STEM) is a powerful technique for characterizing complex nanoscale structures. In this method, a convergent beam electron diffraction pattern (CBED) is acquired at each probe location during the scan of the sample. This means that a 2‐dimensional signal is acquired at each 2‐D probe location, equating to a 4‐D dataset. Despite the recent development of fast direct electron detectors, some capable of 100kHz frame rates, the limiting factor for 4‐D STEM is acquisition times in the majority of cases, where cameras will typically operate on the order of 2kHz. This means that a raster scan containing 256^2 probe locations can take on the order of 30s, approximately 100‐1000 times longer than a conventional STEM imaging technique using monolithic radial detectors. As a result, 4‐D STEM acquisitions can be subject to adverse effects such as drift, beam damage, and sample contamination. Recent advances in computational imaging techniques for STEM have allowed for faster acquisition speeds by way of acquiring only a random subset of probe locations from the field of view. By doing this, the acquisition time is significantly reduced, in some cases by a factor of 10‐100 times. The acquired data is then processed to fill‐in or inpaint the missing data, taking advantage of the inherently low‐complex signals which can be linearly combined to recover the information. In this work, similar methods are demonstrated for the acquisition of 4‐D STEM data, where only a random subset of CBED patterns are acquired over the raster scan. We simulate the compressive sensing acquisition method for 4‐D STEM and present our findings for a variety of analysis techniques such as ptychography and differential phase contrast. Our results show that acquisition times can be significantly reduced on the order of 100‐300 times, therefore improving existing frame rates, as well as further reducing the electron fluence beyond just using a faster camera. [ABSTRACT FROM AUTHOR]

We present a comparison of common electron microscopy sample preparation methods for studying crystallisation processes from solution using both scanning and transmission electron microscopy (SEM and TEM). We focus on two widely studied inorganic systems: calcium sulphate, gypsum (CaSO4·2H2O) and calcium carbonate (CaCO3). We find significant differences in crystallisation kinetics and polymorph selection between the different sample preparation methods, which indicate that drying and chemical quenching can induce severe artefacts that are capable of masking the true native state of the crystallising solution. Overall, these results highlight the importance of cryogenic (cryo)‐quenching crystallising solutions and the use of full cryo‐TEM as the most reliable method for studying the early stages of crystallisation. [ABSTRACT FROM AUTHOR]

Transition metal nitrides, especially tantalum nitrides, are pivotal for applications in extreme environments demanding excellent mechanical properties and thermodynamic stability. Among them, θ$\utheta$‐TaN, a high‐pressure polymorph of tantalum nitride with its exceptional bulk modulus (362 GPa) and hardness (31.7 GPa) promises to have many technological uses. Another nitride, Ta3N5${\rm {Ta}}_3{\rm {N}}_5$, has gained importance as a photocatalyst for water splitting using visible light. The Ta–N phase diagram indicates that the thermal decomposition of pure Ta3N5${\rm {Ta}}_3{\rm {N}}_5$ leads to the formation of ε$\uepsilon$‐TaN. However, Ta3N5${\rm {Ta}}_3{\rm {N}}_5$ usually has some amount of oxygen as an impurity mainly due to its synthesis route. We found that the θ$\utheta$‐TaN phase, which is usually observed at high pressures, is formed during the thermal decomposition of oxygen containing Ta3N5${\rm {Ta}}_3{\rm {N}}_5$. The presence of θ$\utheta$‐TaN is verified using several experimental techniques such as X‐ray diffraction, Raman spectra, high‐angle annular dark field scanning transmission electron microscopy (STEM‐HAADF), and electron energy loss spectroscopy (EELS). Elemental distribution analyzed through energy dispersion X‐ray spectroscopy (XEDS) in STEM reveals about 7 at.% of oxygen in θ$\utheta$‐TaN. First‐principle calculations are performed to examine the thermodynamic stability of oxygen substituted θ$\utheta$‐TaN and pure θ$\utheta$‐TaN via formation enthalpies, elastic constants, and phonon dispersion calculations. The computational studies confirm that oxygen in θ$\utheta$‐TaN enhances its thermodynamic stability. The calculated electron localization functions establish the bonding characteristics between Ta, N, and O, confirming the same. [ABSTRACT FROM AUTHOR]

The efficient removal of Cr(VI) from water is a crucial environmental concern, and in this study, the focus was on addressing this issue by investigating a new flower-like cerium phosphate polyaniline nanocomposite (CePO4-PANI) material. This material was synthesized using an in situ oxidative polymerization method, resulting in a flower-like morphology that was confirmed through field emission scanning electron microscopy and transmission electron microscopy images. The adsorption of Cr(VI) onto the material followed the pseudo-second-order kinetic model and the Langmuir isotherm model, with a high adsorption capacity of 129.87 ± 2.1 mg g−1 at room temperature in a wide pH range of 2 to 6. The CePO4-PANI nanocomposite is a promising adsorbent for the treatment of Cr(VI), with high tolerance to co-anions and efficient regeneration after multiple adsorption-desorption cycles. XPS spectra revealed the simultaneous adsorption of Cr(VI) and in situ chemical reduction to Cr(III) via electrostatic attractions and chelation methods. Its unique flower-like morphology, coupled with its impressive adsorption capacity, co-anion tolerance, and efficient regeneration, make it a promising alternative to existing technologies for water treatment. [ABSTRACT FROM AUTHOR]

Stenotrophomonas maltophilia (S. maltophilia) is a spoilage microorganism widely distributed in vegetables, dairy products, and various environments and can cause serious foodborne illnesses. Renowned for its environmentally friendly, safe, and non-toxic properties, rose essential oil (REO) is widely recognized as an exceptional natural antibacterial agent. In the present study, we conducted a comprehensive analysis to elucidate the inhibition mechanism of REO against S. maltophilia at both cellular and metabolic levels. The results demonstrated that REO treatment of cells resulted in the disruption of cell structure and leakage of cellular contents. Remarkable changes in the morphology of bacterial cells were observed under both scanning electron microscopy and transmission electron microscopy. At the metabolic level, multiple metabolic pathways were disrupted after REO treatment, including amino acid metabolism, nucleotide metabolism, and aminoacyl tRNA biosynthesis. These results shed new light to the inhibition mechanism of REO against S. maltophilia and provide a theoretical basis for the development of effective essential oil preservatives. [ABSTRACT FROM AUTHOR]

Purpose: COVID-19 (coronavirus disease 2019) is an infectious disease caused by SARS-CoV-2, first reported in 2019 in Wuhan, China. Among the common complications is a pro-inflammatory and hypercoagulative response that compromises the vasculature among various organs. Methods: In this report, we present the postmortem retinal findings of five patients observed by means of optical microscopy and transmission and scanning electron microscopy techniques. Results: Clinical manifestations such as retinal hemorrhages and exacerbated inflammatory infiltrate, altered ultra structure with swollen mitochondria and pyknotic cells in both layers of the retina were observed in all analyzed eyes. Conclusion: Our data point to the fragility of this tissue in cases of severe COVID-19. [ABSTRACT FROM AUTHOR]

Understanding the structural stability of nanomaterials such as nanowires is imperative for their practical applications. Here, using single-shot ultrafast transmission electron microscopy, we captured the Plateau-Rayleigh instability behavior of silver nanowires decomposing into silver nanoparticles upon laser irradiation on nanosecond time scales. We found that this dynamic process can be accelerated by a factor of 10 through increasing the peak laser fluence from 6.03 to 14.60 mJ/cm2. Moreover, by comparing the laser fluence required to initiate the Plateau-Rayleigh instability in silver nanowires on carbon and Formvar membranes, it was found that the main driving force for the Plateau-Rayleigh instability in this study was substrate heating. Finite element analysis and molecular dynamics simulations are also applied to estimate the temperature jump of the nanowires and atomistic behavior, respectively. In addition, the complex motions of silver nanowires under laser irradiation were systematically investigated by combining the results of ultrafast transmission electron microscopy with scanning electron microscopy characterizations and were determined to be related to nanowire-membrane interactions or pre-existing stresses on the nanowires, which in turn demonstrated the potential of ultrafast transmission electron microscopy for the characterization of nanomaterials and devices under extreme conditions. [ABSTRACT FROM AUTHOR]

X-ray diffraction (XRD) characterization of Si powder was carried out using synchrotron and laboratory sources. Microstructural (size-strain) analyses of XRD patterns were carried out using the Rietveld refinement method. Experimentally observed super-Lorentzian shapes of the XRD peaks of Si powder were examined using multimodal profile fitting and bimodal model was found to be adequate. The two components obtained using a bimodal approach are referred as narrow and broad profiles based on their estimated relative peak widths. Peak shapes of crystallite size-dependent parts of narrow and broad profiles were found to be almost Gaussian and Lorentzian in nature, respectively. The simultaneous presence of such peak shapes corresponding to a bimodal microstructure is uncommon in literature. Therefore, in order to explore the role of different natures of XRD peak shapes (size dependent) of the bimodal profiles of Si, detailed microstructural analysis was carried out using the complementary method of whole powder pattern modeling (WPPM) and found to be related to the variance of crystallites' size distribution. Additionally, the effect of instrument resolution (laboratory and synchrotron sources) on the microstructural parameters was also studied. Scanning and transmission electron microscopy were used to characterize the morphology of Si powder and correlate with the microstructural findings of XRD methods. [ABSTRACT FROM AUTHOR]

The present study focuses on the phase and structural features of the MnAl intermetallic compound during solid-state synthesis. In this regard, the milling process was done in different Mn50+xAl50-x (0< x< 7.5) powder mixtures and the prepared samples were evaluated using X-ray diffractometer, scanning and transmission electron microscopy, differential thermal analysis and vibrating sample magnetometer. The results showed that the τ-MnAl magnetic phase with L10 structure could not be formed during the milling and low-temperature annealing. During the milling process, Al atoms dissolve in the Mn network and a single β-Mn supersaturated solid solution (SSSS) forms. The β-Mn (SSSS) phase is unstable and transforms into the icosahedral quasi-crystal as well as γ2-Al8Mn5 and β-Mn stable phases during subsequent annealing. [ABSTRACT FROM AUTHOR]

In situ and operando investigation of photocatalysts plays a fundamental role in understanding the processes of active phase formation and the mechanisms of catalytic reactions, which is crucial for the rational design of more efficient materials. Using a custom‐made operando photocatalytic cell, an in situ procedure to follow the formation steps of Pd/TiO2 photocatalyst by synchrotron‐based X‐ray absorption spectroscopy (XAS) is proposed. The procedure resulted in the formation of ∼1 nm Pd particles with a much narrower size distribution and homogeneous spreading over TiO2 support compared with the samples generated in a conventional batch reactor. The combination of in situ XAS spectroscopy with high‐angle annular dark‐field scanning transmission electron microscopy demonstrated the formation of single‐atom Pd(0) sites on TiO2 as the initial step of the photodeposition process. Palladium hydride particles were observed for all investigated samples upon exposure to formic acid solutions. [ABSTRACT FROM AUTHOR]

Chemically ordered face-centered cubic (fcc) phases consisting mainly of Cr, Co, and Ni were synthesized by annealing a Cr26.7Co26.7Ni26.7Si10B5P5 amorphous alloy. The annealed Cr26.7Co26.7Ni26.7Si10B5P5 sample was composed of Cr4.5BP2, Cr3 Co5Si2, and fcc phases. Synchrotron radiation anomalous X-ray scattering (AXS) measurements confirmed that the annealed Cr26.7Co26.7Ni26.7Si10B5P5 sample had superlattice reflections from an L10-, and/or L12-, and D022-type ordered structure. The diffraction intensities of the superlattice reflections observed in the AXS measurements indicated strong dependence on the incident X-ray energy. The diffraction intensity of the superlattice reflection increased at the X-ray energy near the K-edge of Cr, suggesting that Cr is mainly ordered in the L10- and D022-type structures. Microstructural analysis using scanning transmission electron microscopy (STEM) revealed crystal grains with diameters of approximately 20 nm, showing diffraction spots corresponding to superlattice reflections of 001 and 110, in addition to a two-dimensional diffraction pattern corresponding to the fcc structure. Simultaneous STEM--energy dispersive X-ray spectroscopy analysis indicated that the grains had a higher Cr concentration than the mother alloy composition of Cr26.7Co26.7Ni26.7Si10B5P5. [ABSTRACT FROM AUTHOR]

Developing novel lead‐free ferroelectric materials is crucial for next‐generation microelectronic technologies that are energy efficient and environment friendly. However, materials discovery and property optimization are typically time‐consuming due to the limited throughput of traditional synthesis methods. In this work, we use a high‐throughput combinatorial synthesis approach to fabricate lead‐free ferroelectric superlattices and solid solutions of (Ba0.7Ca0.3)TiO3 (BCT) and Ba(Zr0.2Ti0.8)O3 (BZT) phases with continuous variation of composition and layer thickness. High‐resolution x‐ray diffraction (XRD) and analytical scanning transmission electron microscopy (STEM) demonstrate high film quality and well‐controlled compositional gradients. Ferroelectric and dielectric property measurements identify the "optimal property point" achieved at the composition of 48BZT–52BCT. Displacement vector maps reveal that ferroelectric domain sizes are tunable by varying {BCT–BZT}N superlattice geometry. This high‐throughput synthesis approach can be applied to many other material systems to expedite new materials discovery and properties optimization, allowing for the exploration of a large area of phase space within a single growth. [ABSTRACT FROM AUTHOR]

The herbicidal activity of the fermentation broth, filtrate, and extracts of Bacillus altitudinis D30202 was evaluated against seed germination and seedling growth of wild oat (Avena fatua L.). The bacterial culture filtrate exhibited greater inhibition of the wild oat weed than the fermentation broth. The filtrate was also extracted with organic solvents. The herbicidal potency of the extracts on the growth of wild oat plants was as follows: chloroform (100% inhibition of germination) > n-butanol (93.8%) > ethyl acetate (66.7%) > petroleum ether (6.3%) > aqueous phase (2.1%); so the chloroform extract was evaluated further. It inhibited wild oat radicle growth by 100%, and plumule growth by 97.9%, while spraying young plants with a 5 mg/mL extract caused severe desiccation of the leaves, stalk wilting, and plant death. IC50 values for inhibition of plumule and radicle growth and germination were 0.64– 0.72 mg/mL. Scanning electron microscopy and transmission electron microscopy revealed changes in the microstructure of the leaves and root tips, and degradation of organelles following chloroform extract treatment. The 5 mg/mL extract had no adverse impact on the growth or health of highland barley (Hordeum vulgare L.), corn (Zea mays), and broad bean (Vicia faba L.), indicating that this novel bioherbicide is suitable for control of wild oat weeds in the production of these food crops (while having a minor impact on the health of pea plants and being phytotoxic to wheat plants). [ABSTRACT FROM AUTHOR]

We have developed and optimized a method to grow ruthenium films of unprecedented quality. Our three-step process is reminiscent of solid-phase epitaxy. First, c-cut sapphire substrates are terminated at their Al-rich √31 × √31R ± 9° reconstruction by in situ annealing. Second, 3D structured epitaxial Ru films are deposited at low temperatures by laser evaporation of Ru rods. Third, the films, thus, obtained are epitaxially transformed by high-temperature annealing. X-ray diffraction studies reveal good crystallinity of the obtained 15–60 nm-thick films: peak widths of the rocking curve are one order of magnitude smaller than those of the best published films. Scanning transmission electron microscopy and electron energy loss studies show that the interface between the sapphire substrates and the flat Ru films is atomically sharp with very limited intermixing. These results demonstrate the usefulness of postanneal processes for producing high-quality epitaxial films of elemental metals on insulating substrates. [ABSTRACT FROM AUTHOR]

In recent years, the increase in cancer morbidity and mortality has presented scientists with a major challenge in developing new therapeutic agents against cancer cells. This study aims to characterize the anticancer effects of copper oxide nanoparticles (NPs) conjugated with Lapatinib (CuO@Lapatinib) on breast and lung cancer cell lines. The physicochemical properties of the NPs were characterized by fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning and transmission electron microscopy, energy dispersive X-ray spectroscopy (EDS), dynamic light scattering (DLS), and zeta potential analyses. The antiproliferative potential of the NPs in the breast (MDA-MB-231) and lung (A549) cancer cell lines and a normal cell line (MRC5) was investigated by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay. Flow cytometry and Hoechst staining were used to evaluate cell apoptosis and cell cycle analysis. The reactive oxygen species (ROS) levels in the treated and control cells were also determined. The NPs were spherical, with a size range of 20-59nm, a DLS size of 338nm, and a zeta potential of -42.9 mV. The half maximal inhibitory concentration (IC50) of CuO@Lapatinib NPs for the normal, breast cancer, and lung cancer cell lines was 105, 98, and 87 µg/ml, respectively. Treatment with CuO@Lapatinib NPs caused considerable apoptosis induction in breast cancer (from 0.65% to 68.96%) and lung cancer cell lines (from 1.11% to 44.11%). Also, an increased level of cell cycle arrest at the S phase was observed in both cancer cell lines. The ROS level in the breast and lung cancer cell lines after treatment with CuO@Lapatinib NPs increased by 3.45 and 21.04 folds, respectively. Nuclear morphological alterations, including chromatin condensation and fragmentation, were observed in both cancer cell lines. This study indicates CuO@Lapatinib is a potent antiproliferative compound with more efficient inhibitory effects on lung cancer than breast cancer cells, which can be related to the higher ROS generation in the A549 cell line. [ABSTRACT FROM AUTHOR]

Zero-valent iron nanoparticles (ZVINs) as a new environment remediation technology has significant potential for the treatment of contaminated soil and groundwater. In spite of the high efficiency of ZVINs in the removal of various pollutants from porous media, their have some weaknesses such as lack of stability and a strong tendency to rapidly aggregate which limits their application in field scales. The main objectives of this study was to investigate the efficency of guar gum (GG), polyacrylamide (PAM), polystyrene sulfonate (PSS), polyvinylpyrrolidone (PVP) stabilized-ZVINs (GG-ZVINs, PAM-ZVINs, PSS-ZVINs and PVP-ZVINs) and non-stabilized (bare) ZVINs (Bare-ZVINs) on nitrate removal from sand-packed columns. The characteristics of the synthesized ZVINs were characterized by scanning and transmission electron microscopy (SEM, TEM), zeta-potential analyzer and X-ray diffraction (XRD) techniques. A series of transport experimaent on sand-packed column were conducted under different concentrations of ZVINs (1, 2, and 3 g/L) and initial nitrate concentration (150, 250, and 350 mg/L). The CXTFIT code was used to simulate nitrate reduction in the sand columns; and estimating the transport parameters. The results revealed that mechanisms such as straining, ripening and aggregation had a considerable impact on the ZVINs transport in porous media. The results indicated that by increasing nitrate concentration the removal efficiency was decreased and in contrast by increasing concentrations of the ZVINs the nitrate reduction potential showed an enhancing trend. The results also revealed that ZVINs had a potential for nitrate removal from sand columns upon the following order: PAM-ZVINs > GG-ZVINs > PSS- ZVINs > PVP- ZVINs > Bare- ZVINs. [ABSTRACT FROM AUTHOR]

This study was conducted to extend our previous investigations to examine the cytotoxic efficacy of Smp43 scorpion peptide against colorectal cancer cell line (HCT-116) and revealing its molecular mechanisms of action. Using MTT assay, Smp43 significantly induced cytotoxic effects on HCT-116 cancer cells compared to normal colon epithelial cell line (FHC) of IC50 4.11 and 62.17 µg/ml, respectively. Flow cytometric apoptosis assay showed that IC50 (4.11 µg/ml) of Smp43 induced a remarkable increase in the proportion of HCT-116 cancer cells undergoing late apoptotic cell death. Also, Smp43 caused cell cycle arrest at the S phase. RT-PCR analysis showed highly significant downregulation of Bcl-2 anti-apoptotic gene and ki-67 proliferative markers in HCT-116 treated with IC50 of Smp43. In contrast, caspase-3, −8, −9, Bax, and p53 apoptotic genes were upregulated. Protein expression levels of caspase-3, −8, −9, and p53 were similarly elevated in treated cells using a western blot analysis. The apoptotic characteristics were also confirmed through scanning and transmission electron microscopy. The Smp43 treated HCT-116 cancer cells showed cell membrane blebbing, pore formation, heterochromatin condensation toward the nuclear envelope, leakage of cell organelles, and formation of apoptotic bodies. Consequently, Smp43 peptide provides a great starting point for creating effective cytotoxic agents against human colorectal cancer. [ABSTRACT FROM AUTHOR]

This study presents a novel approach to synthesize zinc oxide (ZnO) nanoparticles using a polymer precursor method, offering precise control over particle size in the nanometer scale. Zinc oxide nanoparticles are of significant interest due to their wideranging applications in various fields such as solar cells, gas sensors, photocatalysts, and nanomedicines. The synthesized nanoparticles were thoroughly characterized using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Fourier Transform Infrared spectroscopy (FTIR). The distinct hexagonal form detected in the XRD pattern, featuring characteristic reflection planes at angles of 31.72° (100), 34.39° (002), 36.23° (101), and 47.44° (102), signifies the synthesis of ZnO possessing a hexagonal wurtzite structure. The SEM and TEM images revealed uniformly spherical particles with an average size ranging from 35 to 40 nm. Such uniform morphology and size distribution are critical for ensuring consistent performance in applications such as gas sensing and catalysis. Additionally, the FTIR spectra indicated a reduction in impurities after the synthesis process, highlighting the effectiveness of the polymer precursor method in producing high-quality ZnO nanoparticles. Heating the ZnO precursor material at 400°C for 2 hours significantly reduces impurities, suggesting conversion to ZnO nanoparticles. [ABSTRACT FROM AUTHOR]

Infinite-layer nickelates stand as a promising frontier in the exploration of unconventional superconductivity. Their synthesis through topotactic oxygen reduction from the parent perovskite phase remains a complex and elusive process. This study delves into the nano-scale effects of the topotactic lattice transformation within LaNiO2 crystals. Leveraging high-resolution scanning transmission electron microscopy and spectroscopy, our investigations uncover a panorama of structural alterations, including grain boundaries and coherent twin boundaries, triggered by reduction-induced transformations. In addition, our analyses unveil the formation of an oxygen-rich disordered transition phase encircling impurities and pervading crystalline domains and the internal strain is accommodated by grain boundary formation. By unraveling these nano-scale effects, our findings provide insights into the microscopic intricacies of the topotactic reduction process elucidating the transition from the perovskite to the infinite-layer phase within nickelate bulk crystals. [ABSTRACT FROM AUTHOR]

The Bi–Te binary system, characterized by the homologous series of (Bi2)m(Bi2Te3)n, has always attracted research interest for its layered structures and potential in advanced material applications. Despite the fact that Bi2Te3 has been extensively studied, the exploration of other compounds has been constrained by synthesis challenges. This study reports the molecular beam epitaxy growth of FeTe on Bi2Te3, demonstrating that varying growth conditions can turn the Bi2Te3 layer into different Bi–Te phases and form corresponding FeTe/Bi–Te heterostructures. Our combined analysis using reflection high-energy electron diffraction, high-resolution x-ray diffraction, and high-resolution scanning transmission electron microscopy indicates that specific growth conditions used for the growth of the FeTe layer can facilitate the extraction of Te from Bi2Te3, leading to the formation of Bi4Te3 and Bi6Te3. In addition, by lowering the FeTe growth temperature to 230 °C, Te extraction from the Bi2Te3 layer could be avoided, preserving the Bi2Te3 structure. Notably, all three FeTe/Bi–Te structures exhibit superconductivity, with the FeTe/Bi2Te3 heterostructure enjoying the highest superconductivity quality. The results of magneto-transport measurements indicate that the induced superconductivity displays a three-dimensional nature. These findings introduce a novel method for realizing Bi4Te3 and Bi6Te3 through Te extraction by growing FeTe on Bi2Te3, driven by the high reactivity between Fe and Te. This approach holds promise for synthesizing other members of the Bi–Te series, expanding the functional potential of these materials. [ABSTRACT FROM AUTHOR]

Superconducting films of α-Ta are promising candidates for the fabrication of advanced superconducting qubits. However, α-Ta films suffer from many growth-induced structural inadequacies that negatively affect their performance. We have therefore explored a new synthesis method for α-Ta films, which allows for the growth of these films with an unprecedented quality. Using this method, high quality α-Ta films are deposited at a comparably high substrate temperature of 1150 °C. They are single-phase α-Ta and have a single out-of-plane (110) orientation. They consist of grains ≥2 μm that have one of three possible in-plane orientations. As shown by scanning transmission electron microscopy and electron energy loss studies, the substrate–film interfaces are sharp with no observable intermixing. The obtained insights into the epitaxial growth of body-centered-cubic films on quasi-hexagonal substrates lay the basis for harnessing the high structural coherence of such films in various applications. [ABSTRACT FROM AUTHOR]

We investigate the composition of α-phase intermediate layers at epitaxial Ga2O3/Al2O3 interfaces using high angle annular dark field scanning transmission electron microscopy. Their presence is considered a general phenomenon as they are observed independent of the growth technique [Schewski et al., Appl. Phys. Exp. 8, 011101]. Samples were grown by plasma assisted molecular beam epitaxy using different growth conditions. Almost independent of these, the quantitative evaluation of the measured intensities gave Ga concentrations of ∼25%. We show that the previously published model, based on a pure α-Ga2O3 interlayer, fails if it is adapted to the measured composition. Density functional theory (DFT) computations were used to overcome the approximations made in this model and suggest that a stabilization of the layer is possible due to the low Ga concentration (≤ 35%) at which the α-phase is the most stable. Our surface model computations suggest an exchange of Ga atoms at the surface with Al atoms from the underlying substrate as a possible formation mechanism. [ABSTRACT FROM AUTHOR]

In a scanning transmission electron microscope (STEM), producing a high-resolution image generally requires an electron beam focused to the smallest point possible. However, the magnetic lenses used to focus the beam are unavoidably imperfect, introducing aberrations that limit resolution. Modern STEMs overcome this by using hardware aberration correctors comprised of many multipole elements, but these devices are complex, expensive, and can be difficult to tune. We demonstrate a design for an electrostatic phase plate that can act as an aberration corrector. The corrector is comprised of annular segments, each of which is an independent two-terminal device that can apply a constant or ramped phase shift to a portion of the electron beam. We show the improvement in image resolution using an electrostatic corrector. Engineering criteria impose that much of the beam within the probe-forming aperture be blocked by support bars, leading to large probe tails for the corrected probe that sample the specimen beyond the central lobe. We also show how this device can be used to create other STEM beam profiles such as vortex beams and probes with a high degree of phase diversity, which improve information transfer in ptychographic reconstructions.

In this work, we report quantitative morphometry of freeze-dried graphene-based aerogels (i.e., graphene aerogel-GA, nitrogenated GA-NGA, graphene-carbon nanotube hybrid-Gr-MWCNTs, carbon foam-CF, and CF-GA hybrid-CF-GA) and monoliths, prepared by hydrothermal and organic sol-gel methods, respectively. X-ray micro-computed tomography (XMCT) in combination with scanning and transmission electron microscopy allowed visualization of internal microstructures in three-dimensional space. Quantitative morphometry analysis through the reconstructed volume renderings from two-dimensional sliced images revealed hierarchical structures possessing interlaced thin sheets, honeycomb organization, and topological interconnected pore background domains. The influence of small-diameter functionalized multi-walled carbon nanotubes (MWCNTs) inclusions to graphene-like sheets and integration with CF is assessed through quantitative morphometry analysis in terms of volume-weighted pore size, wall thickness, and porosity levels. Hybrid composite porous solids elucidated cross-linking reinforced by a homogeneous distribution of CNTs into complex sheets of GA and CF matrices. A consistent trend impacting porosity and interconnectedness was found following NGA ≥ GA > CF > Gr-MWCNT2:1 > CF-GA > Gr-MWCNT3:1 > Gr-MWCNT5:1, from XMCT image processing and analyses in corroboration with physical properties and reliability. The experimental results provide insights and guide the design of characteristic porous carbonaceous and graphene-based functional nanomaterials for energy sciences, environmental engineering, and fundamental reactive transport of fluids. [ABSTRACT FROM AUTHOR]

The structure, composition, and spatial distribution heterogeneity of artificial pinning centers affect the critical current density of REBa2Cu3O7−y (RE: rare earth) coated conductors. Nanoscale structures and compositions have been analyzed with transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). However, microscale heterogeneity has been difficult to characterize. Here, YBa2Cu3O7−y thin films doped with double-perovskite Ba2YbNbO6 were prepared via pulsed-laser deposition and characterized with TEM, STEM, and scanning electron microscopy (SEM). Cross-sectional and plan-view TEM/STEM imaging revealed hybrid pinning structures consisting of nanorods, nanoparticles, and planar defects that were formed spontaneously. Nanorods were imaged with high spatial resolution via field-emission SEM of thin-foil specimens. Focused-ion-beam (FIB) micro-sectioning enables SEM imaging of microscale heterogeneity in nanorod spatial distributions. By using TEM/STEM in conjunction with FIB-SEM, the coated conductor inhomogeneity was directly evaluated from the nano- to micrometer scales. [ABSTRACT FROM AUTHOR]

Epitaxial lift-off (ELO) of high-quality GaN layers allows for integration with a variety of materials enabling improved performance, reduced costs, and development of new electronics. Of the ELO technologies, two-dimensional (2D) material-based lift-off offers great promise but is still in the early stages of development and has yet to demonstrate the scale and yield of other ELO technologies. Here, we demonstrate the potential of this process's scalability, speed, and yield through epitaxial growth and lift-off of 4-in. GaN films using a 2D boron nitride (BN) van der Waals (vdW) buffer layer. Since the BN layer acts as the growth template and the mechanical release layer, both the quality and adhesion of the GaN layer are correlated with the BN morphology and uniformity. Detailed spectroscopic mapping demonstrates excellent BN uniformity, which translates into growth of high-quality GaN as shown in mapping of the x-ray rock curves (XRCs), atomic force microscopy, and photoluminescence. Scanning transmission electron microscopy and electron energy loss spectroscopy reveal abrupt chemically distinct interfaces between the sapphire, BN, and AlN/GaN layers essential for efficient lift-off. Combined with the BN/GaN vdW heterostructure, Ni spalling is used to efficiently lift-off and transfer a full 4-in. GaN layer. Post transfer characterization of a 1.9 μm thick GaN layer transferred to a SiO2/Si wafer shows a very minimal change in the XRC and photoluminescence. Strain measurements before and after transfer show that the process fully relaxes residual strain formed in the GaN during high-temperature growth. This work highlights the potential for industry scalability of an exciting 2D material-based lift-off technology, which can facilitate higher power and more efficient radio frequency devices. [ABSTRACT FROM AUTHOR]