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III-nitride materials, such as GaN and its alloys, are essential for modern microelectronics and optoelectronics due to their unique properties. Focused ion beam (FIB) techniques play a crucial role in their prototyping and characterization at the micro- and nanoscale. However, conventional FIB milling with Ga ions presents challenges, including surface amorphization and point defect introduction, prompting the exploration of alternative ion sources. Xenon-based inductively coupled plasma or plasma FIB has emerged as a promising alternative, offering reduced damage and better sample property preservation. Despite extensive research on FIB-induced damage in GaN, systematic comparisons between Ga and Xe ion milling on the luminescence characteristics of GaN remain limited. This study aims to fill this gap by evaluating and comparing the extent of FIB-induced damage caused by Ga and Xe ions in wurtzite and zincblende GaN through cathodoluminescence measurements. Our findings indicate that Xe ion milling yields higher integrated intensities compared to Ga ion milling, attributed to shallower implantation depths and reduced lattice disorder. We also observe a decrease in integrated intensity with increasing ion beam acceleration voltage for both wurtzite and zincblende GaN layers. This study provides valuable insights into optimizing FIB-based sample preparation techniques for III-nitride materials, with implications for enhancing device performance and reliability. [ABSTRACT FROM AUTHOR]

This paper explores the fundamental structural origins of the 0.7 eV band emission peak, known as D07. The increased attention on these d-band emission lines originates mainly from the correlation between crystal defect and the intensified recombination of less dominant charge carriers. This association holds substantial importance, impacting not just the electronics sector but also raising concerns about reduced efficiency in silicon solar cells. By employing hyperspectral photoluminescence imaging, we pinpointed regions manifesting high D07 peak emissions on a microscopic scale. Subsequently, we conducted a structural investigation utilizing scanning electron microscopy and electron backscatter diffraction. Following this, we used a focused ion beam to extract areas of interest, allowing for a detailed characterization of the sample using high-resolution scanning transmission electron microscopy at the atomic scale. This approach aids in identifying defects and determining grain boundary orientation. In areas of high D07 band emission, we found Σ 3 { 114 } { 101 } grain boundaries decorated with two-layer fault twin and/or an extrinsic two-layer stacking faults. In addition, density functional theory calculations suggest oxygen impurities as a possibility for substitutional segregation to these types of defects. It is therefore plausible that the D07 line might be attributed to stacking faults featuring oxygen agglomerates. [ABSTRACT FROM AUTHOR]

Lithium niobate ( LiNbO 3 , LN) on insulator (LNOI) has emerged as a promising platform for integrated photonics, due to the strong optical confinement and excellent nonlinear optical and electrical characteristics of LN crystal. Focused ion beam (FIB) as a versatile technique has become a typical way to fabricate LNOI microstructures. However, due to the bombardment of Ga + ions during fabrication, the LN lattice is damaged, which would deteriorate the performance of LNOI devices. Thus, the recognition of the damage formed by FIB fabrication is necessary for the control and optimization of the properties of LN microstructures. However, previous studies on this issue have not delved into it from a lattice perspective. Here, we conducted an investigation into the damage inflicted on LN film due to FIB fabrication and the subsequent impact of buffered oxide etching (BOE) treatment on this damage using Raman spectroscopy. Our findings indicate that the interaction between Ga + ions and LN film results in lattice amorphization, as well as a reduction in the ionic bonding and lattice stress within LN. Furthermore, absorption spectra were acquired both before and after BOE treatment, revealing the emergence of additional optical losses attributed to Ga + ions. Notably, these defects responsible for optical losses are predominantly concentrated near the surface of the milled LN film, and BOE treatment proves efficient in their removal. This study contributes to further understanding of the defect structure in LN film after FIB fabrication, as well as repairing the damage and, thus, improving the performance of LN microstructures. [ABSTRACT FROM AUTHOR]

Recent research on a special type of sexual reproduction and zygospore formation in Zygnematophyceae, the sister group of land plants, is summarized. Within this group, gamete fusion occurs by conjugation. Zygospore development in Mougeotia, Spirogyra and Zygnema is highlighted, which has recently been studied using Raman spectroscopy, allowing chemical imaging and detection of changes in starch and lipid accumulation. Three-dimensional reconstructions after serial block-face scanning electron microscopy (SBF-SEM) or focused ion beam SEM (FIB-SEM) made it possible to visualize and quantify cell wall and organelle changes during zygospore development. The zygospore walls undergo strong modifications starting from uniform thin cell walls to a multilayered structure. The mature cell wall is composed of a cellulosic endospore and exospore and a central mesospore built up by aromatic compounds. In Spirogyra, the exospore and endospore consist of thick layers of helicoidally arranged cellulose fibrils, which are otherwise only known from stone cells of land plants. While starch is degraded during maturation, providing building blocks for cell wall formation, lipid droplets accumulate and fill large parts of the ripe zygospores, similar to spores and seeds of land plants. Overall, data show similarities between streptophyte algae and embryophytes, suggesting that the genetic toolkit for many land plant traits already existed in their shared algal ancestor. This article is part of the theme issue 'The evolution of plant metabolism'. [ABSTRACT FROM AUTHOR]

In GaN‐on‐Si nanowire integration schemes, where the nanowires are contacted through the substrate, the interfaces between silicon substrate, AlN buffer layer, and GaN nanowire are of high interest. Herein, analysis by scanning transmission electron microscopy (STEM) of GaN nanowires grown on Si(111) by metal–organic vapor phase epitaxy using a polarity‐ and site‐controlled growth method is presented. This method is based on prestructuring the substrate, ex situ oxidation of the surface, and in situ oxide layer desorption. First, an AlN layer is grown to prevent melt‐back etching. Samples are prepared for STEM by focused ion beam cutting. STEM measurements in three different regions reveal that the AlN buffer material is polycrystalline. The degree of polycrystallinity is found to depend on the observed region: the highest degree exists at the field area between nanowires and the lowest at the sidewall of the Si‐pillars. On the sidewall, the c→$$ \overrightarrow{c} $$‐direction of the AlN grain is tilted by 30.1° with regard to the Si{111} sidewall plane, leading to reduced lattice mismatch at this location. The growth of GaN is competing with diffusion of Ga atoms through grain boundaries. The dominant mechanism is dependent on the region, leading to site‐controlled growth of nanowires. [ABSTRACT FROM AUTHOR]

Nitrocellulose (NC) finds widespread use in propellants and launchers. Nanoscale modification can effectively enhance its combustion performance by shortening the mass and heat transfer distance. However, it also presents greater safety challenges for storage and application. To further investigate the thermal safety characteristics of nanoscale NC, this study explores the impact of additives on nanoscale NC. Nanoscale NC was prepared via electrospinning, and the samples were characterized using focused ion beam scanning electron microscopy to examine the influence of precursor concentration and stabilizer on sample morphology, leading to the formulation determination. Samples incorporating triphenylamine and lithium carbonate (Li2CO3) were fabricated using both electrospinning and traditional mechanical mixing techniques. Following preparation, fourier transform infrared spectroscopy, the methyl violet test, and thermogravimetry–differential scanning calorimetry were performed on six samples, each prepared using different methods and additives. These analyses aimed to investigate the thermal decomposition characteristics of the samples under varying heating rates. The study also compared the impact of nanoscale modification on the thermal performance of composite nitrocellulose. Various model-free methods were employed to calculate the relationship between activation energy and conversion rate and to analyze alterations in activation energy. Considering the thermal decomposition characteristic parameters, the study delved into the stabilizing effect of typical stabilizers in nanocomposite fibers. This research is instrumental in guiding preparation process optimization, promoting the application of NC-stabilizer mixtures, and providing valuable references for the preparation and thermal stability investigations of similar nanomaterials. [ABSTRACT FROM AUTHOR]

Owing to its peculiar non‐diffraction, self‐acceleration, and self‐healing properties, the Airy beam has attracted a great deal of attention in various fields such as micro‐manipulation, plasma generation, and optical microscopy. To date, it is still a challenge to generate nonlinear Airy beams with microstructure efficiently, thus limiting applications of such Airy beams. Here, a novel and efficient method for generating Airy beams is experimentally demonstrated by microstructure on a nonlinear crystal surface, which is fabricated by a focused ion beam (FIB) technique. The second‐harmonic (SH) Airy beams are generated in the far field and characterize their intensity distributions, which agree well with theoretical results. Then, the self‐accelerating and self‐healing properties of the generated SH Airy beams are demonstrated. Besides, the normalized efficiency of SH Airy beams is measured at (1.44 × 10−5%W−1), and compare the efficiency of different methods of generating nonlinear Airy beams, which shows the advantages of this method. The proposed method of generating nonlinear Airy beams shows great potential for integrated optics, optical micro‐machining, and advanced imaging. [ABSTRACT FROM AUTHOR]

In the design of optical devices and components, geometric structures and optical properties of materials, such as absorption, refraction, reflection, diffraction, scattering, and trapping, have been utilized. Finding the ideal material with certain optical and geometric characteristics is essential for a customized application. Herein, unoxidizable achromatic copper films (ACFs) are fabricated on Al2O3 substrates utilizing an atomic sputtering epitaxy apparatus. ACFs are made up of two regions vertically: a comparatively flat layer region and a 3D porous nanostructured region on top of the flat region. The measured specular reflectance displays low‐pass filter behavior with a sharp cutoff frequency in the infrared spectrum. Furthermore, the measured diffusive reflectance spectra show light‐trapping behavior in the spectral region above the cutoff frequency, where there are no known absorption mechanisms, such as phonons and interband transitions. A focused ion beam scanning electron microscope is utilized to study the thin film's nanostructured region through 3D tomographic analysis in order to comprehend the phenomena that are observed. This work will shed fresh light on the design and optimization of optical filters and light‐trapping employing porous nanostructured metallic thin films. [ABSTRACT FROM AUTHOR]

Herein, integrating GaN quantum dots (QDs) within a resonant cavity is focused on. Utilizing metal‐organic vapor phase epitaxy, controlled growth of GaN QDs on AlN is achieved. A deep‐UV distributed Bragg reflector (DBR) with high reflectivity in the 250–300 nm range, using AlN and Al0.7Ga0.3N layers to maximize refractive index contrast, is developed. A 50‐period DBR achieves 98% reflectivity at a wavelength of 272 nm. Scanning transmission electron microscopy and electron energy loss spectroscopy analyses reveal a trisection of DBR periods, attributed to a Ga composition pulling effect during growth. The real structure's reflectivity is simulated and matched well with measured data, though actual reflectivity is lower than the ideal. Cathodoluminescence studies at T = 17 K show emission peaks from both the DBR and the GaN QDs. Further, single‐photon emission is demonstrated with a g(2)(t = 0) value of 0.41 at 272.7 nm, confirming the potential for deep‐UV single‐photon sources. Additionally, the creation of a planar resonant cavity with enhanced emission intensity and vertical nanopillar structures with an aspect ratio of 11 and a diameter of 400 nm confirm the successful integration of GaN QDs in advanced UV photonic structures. [ABSTRACT FROM AUTHOR]

A thorough procedure was developed to efficiently manufacture dogbone samples using focused ion beam (FIB) milling for micro-tensile testing. A Bruker PI 89 PicoIndenter, Billerica, MA, USA, was used as a case study, although the analysis and results are applicable to other micro-mechanical testing systems capable of mounting a standard, Ø12.7 mm × Ø3.2 mm pin, scanning electron microscopy (SEM) pin stub (Ted Pella, Redding, CA, USA). Nine dogbones were made from an Fe-45Cu alloy additively manufactured using powder-fed laser-directed energy deposition (DED-LB). Testing showed that fracture was confined to the gauge section for all dogbones and that the fracture mode, ductile vs. brittle, was entirely dependent on the grain orientation relative to the loading direction. The analysis showed that the measured plastic strain to failure can vary from >11% (optimal geometry) to <1% (non-optimal geometry) in micro-tensile testing of high-tensile-strength (>1 GPa) metallic materials. Subsequently, a finite element analysis (FEA) was conducted to identify the improved dogbone geometries. A total of ten thousand dogbone geometries were tested, and their dimensions were defined by a set of four adjustable parameters (corner radius, load surface angle, load surface length, and dogbone head length). The gauge width and gauge length were fixed to 4 µm and 10 µm, respectively. Three-dimensional surface plots of the stress concentration as a function of two parameters were used to identify the optimal ranges of parameter values. The addition of maximum width and length constraints, measuring 25 µm and 30 µm, respectively, allowed us to identify an optimal geometry at load surface angles of 30° and 45°. Their respective dimensions (corner radius, load surface length, and dogbone head length) are, in µm, 12, 6, and 7 and 10, 7, and 7. Testing these two optimal geometries with a range of gauge lengths from 4 to 20 µm showed that smaller gauge lengths only slightly reduced the detrimental stress concentration outside the gauge section. However, smaller gauge lengths will notably improve the FIB surface polishing step as tapering is reduced with smaller dogbone lengths. [ABSTRACT FROM AUTHOR]

As a hydrocarbon reservoir rock, shale is generally composed of highly compacted clay particles with submicrometer sizes and includes nanometric porosity and different hard particles, like quartz, pyrite, etc. One of the key reasons for the formation of a complex fracture network via hydraulic fracturing is the multiscale heterogeneity of shale, especially heterogeneity on the microscale. This paper conducted on an experimental investigation of shale and explored the intrinsic relationship between the microstructure, the related mechanical properties at the micrometer level and the anisotropic failure mechanism. Small-scale specimens with micrometer dimensions in the form of cantilever beams with rectangular cross-section were fabricated by means of a focused ion beam (FIB) and tested via bending with a nanoindenter. The load–deflection curves of these bending beams were monitored up to failure, and the tensile strength of the shale composite was directly derived from the load–deflection curves at 474.5 MPa (parallel to the bedding plane) and 168.9 MPa (vertical to the bedding plane). The results show that the strength anisotropy of shale at the micrometer scale is driven by the clay particles and other minerals, and the bonds of these particles. The modulus anisotropy of the shale composite at the microscale is dominated by the orientation of clay particles. Moreover, the shale composite embedded with pyrite exhibited strong softening characteristics. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing is commonly used in the stimulation of shale reservoirs for sustainable production and commercial development. The fracturing mechanisms of shale matrix, especially the roles of micro pores and minerals, is of vital importance for our understanding of hydraulic fracturing treatments. In this study, we induced hydraulic fractures in laboratory by performing hydraulic fracturing experiments, and observed two dimensional and three dimensional structures of micro-scale cracks in the shale matrix before and after hydraulic fracturing treatment using scanning electron microscopy (SEM) and focused ion beam scanning electron microscope (FIB-SEM) tests. We also counted the probability of different cracking modes and analyzed the relationships between crack pathways and the distributions of minerals, organic matters and pores. The results showed that the cracks mainly propagated along the boundaries of different minerals. The intergranular and organic pores can be captured by the induced cracks, and the intraparticle pores are hard to be reactivated. The present study provides us more evidences for further study of fracturing mechanism in shale matrix. Highlights: The three dimensional structure of shale matrix before and after hydraulic fracturing were observed to demonstrate the efficiency of fracturing treatment. The relationship between the micro scale cracks between and the organics and minerals in shale matrix were investigated. The capture behaviors of different kinds of pores by micro cracks were revealed. [ABSTRACT FROM AUTHOR]

Background: The size effect and deformation instability exhibited by materials at the micro- and nano-scale constrain the development and application of miniaturized devices. Introducing different defects in materials through different technical means to improve the deformation stability of materials has been the main research point of micro- and nano mechanics. Objective: This paper presents a novel strategy to completely eliminate the instability of microscopic deformations by the introduction of high-density precipitates in aluminum alloys by means of suitable heat treatment. Methods: A suitable heat treatment is used to introduce a high density of precipitates in the 7075 aluminum alloy. Using the Focused Ion Beam technique and in situ micropillar compression tests, micron-sized single-crystal micropillars were fabricated and the size dependence of the strength and strain-hardening behavior of 7075 aluminum alloy was systematically analyzed. Results: Compared with precipitate-free Al–Mg alloy micropillars, the micropillars fabricated from 7075 aluminum alloy exhibited more stable deformation behavior, predominantly due to the impediment of dislocation motion by precipitates. The power-law exponent for yield strength relative to pillar size was determined to approach a near-zero value, indicating a negligible dependency of yield strength on specimen size. Similarly, the smaller the size of micropillar, the higher the hardening rate, which can be rationalized by exhaustion hardening. Conclusions: The proposed method can eliminate the size effect of materials with pillar size above 0.5 μm and leads to a stabilization in deformation behavior. These are advantageous for the application of micro- and nano-sized components in advanced engineering systems. [ABSTRACT FROM AUTHOR]

This study investigated the effect of various storage media on the physicochemical properties of plasma-treated 3-mol% yttria-stabilized tetragonal zirconia: air, vacuum, deionized water (DIW), and plasma-activated water (PAW). Each group was divided into five subgroups based on storage periods: immediately after NTP irradiation (T0), and after 1 week (T1), 2 weeks (T2), 3 weeks (T3), and 4 weeks (T4). The control group (C) received no treatment. The storage groups were monitored weekly using various analytical techniques, including contact angle measurements, scanning electron microscopy (SEM), focused ion beam (FIB)-SEM, confocal laser scanning microscopy (CLSM), x-ray photoelectron spectroscopy (XPS), and x-ray diffraction (XRD). Our results demonstrate that plasma-treated zirconia surfaces stored in DIW retained or even increased their hydrophilicity due to the formation of hydrogen bonds and preservation of nitrogen functionalities. In contrast, surfaces stored in air exhibited significant hydrophobic recovery. FIB-SEM analysis showed no adverse internal structural changes regardless of storage medium. The roughness of the zirconia surface slightly increased after plasma treatment and was generally retained across all storage groups for 4 weeks, except for the air storage group. This study concludes that storage in DIW effectively preserves the enhanced surface properties of plasma-activated zirconia for up to 4 weeks. [ABSTRACT FROM AUTHOR]

Mixed matrix membranes (MMMs) have emerged as promising materials for various separation processes due to their tunable properties, enhanced separation performance and reproducibility. In this review paper, we provide a comprehensive overview of the methodologies, challenges, and applications associated with the characterization of MMMs using two advanced imaging techniques: Focused Ion Beam Scanning Electron Microscopy (FIB‐SEM) and Transmission Electron Microscopy (TEM). We begin by outlining the principles and capabilities of FIB‐SEM and TEM, emphasizing their suitability for studying the microstructure, morphology, and composition of MMMs at nanoscale resolution. Subsequently, we discuss the specific challenges and limitations encountered in the characterization of MMMs using these techniques, including sample preparation, image acquisition, and data interpretation. Furthermore, we review the diverse applications of FIB‐SEM and TEM in elucidating the structure‐property relationships of MMMs. Through illustrative examples, we highlight the valuable insights gained from these imaging techniques in optimizing MMMs for various separation applications. Finally, we propose future directions and emerging trends in MMM characterization, including the integration of lasers into FIB‐SEM and in situ characterization techniques, to address current challenges and push the boundaries of MMM design and performance. Overall, this review provides a comprehensive overview of the state‐of‐the‐art methodologies for characterizing MMMs using FIB‐SEM and TEM, identifies key challenges, and offers insights into future research directions aimed at harnessing the full potential of MMMs for sustainable separation technologies. [ABSTRACT FROM AUTHOR]

Accurate modeling of lithium-ion battery (LIB) electrode microstructures provides essential references for understanding degradation mechanisms and optimizing materials. Traditional segmentation methods often struggle to accurately capture the complex microstructures of porous LIB electrodes in focused ion beam scanning electron microscopy (FIB-SEM) data. In this work, we develop a deep learning model based on the Swin Transformer to segment FIB-SEM data of a lithium cobalt oxide electrode, utilizing fused secondary and backscattered electron images. The proposed approach outperforms other deep learning methods, enabling the acquirement of 3D microstructure with reduced particle elongated artifacts. Analyses of the segmented microstructures reveal improved electrode tortuosity and pore connectivity crucial for ion and electron transport, emphasizing the necessity of accurate 3D modeling for reliable battery performance predictions. These results suggest a path toward voxel-level degradation analysis through more sensible battery simulation on high-fidelity microstructure models directly twinned from real porous electrodes. [ABSTRACT FROM AUTHOR]

Tristructural isotropic (TRISO) fuel particles, developed for use in high‐temperature gas‐cooled nuclear reactors, can be subjected to oxidizing environments in off‐normal accident scenarios. In this study, surrogate TRISO fuel particles were oxidized at 1000–1350°C for 4 h in 20 kPa water vapor atmosphere balanced with ultrahigh‐purity helium gas. The oxide scale morphology and thickness were studied via scanning electron microscopy, focused ion beam, and transmission electron microscopy. The oxide thickness increased as the oxidation temperature was increased. Although the oxide scale at 1000°C was completely amorphous, pockets of crystalline oxide were observed on particles oxidized at 1200 and 1300°C. Kinetic analysis was performed to deduce the oxidation mechanism by determining the apparent activation energy using linear regression analysis. The oxidation mechanism was consistent for temperatures from 1000 to 1200°C with an activation energy of 412.4 ± 8.8 kJ/mol. The activation energy then dropped to approximately 201 ± 7.1 kJ/mol for temperatures 1200–1350°C. Therefore, there is a change in oxidation mechanism at ∼1200°C. This change is attributed to the existence of a network of significant bubbles in the oxide layer at higher temperatures, which serve as rapid diffusion pathways for the transport of oxidants from the surface to the SiC/SiO2 interface, instead of relying on the bulk diffusion through the SiO2 layer at lower temperatures where only small bubbles are present along the SiC/SiO2 interface. [ABSTRACT FROM AUTHOR]

It is known that X‐ray CT of organic polymer materials usually provides low‐contrast images because of the low X‐ray absorption of these materials. In this paper, we describe a new method to enhance the contrast of X‐ray CT images of organic polymer materials. We demonstrate that gamma‐ray irradiation of poly (ethylene terephthalate) (PET) fibers in dichloromethane containing 2‐bromoethyl methacrylate, 2‐chloroethyl methacrylate, or 4‐bromostyrene results in the grafting of halogen‐containing oligomeric chains onto the PET fibers. Focused ion beam scanning electron microscopy (FIB‐SEM) and time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) analyses revealed a homogeneous distribution of bromine atoms within the 2‐bromoethyl methacrylate‐modified PET fibers, not only on the surface. This uniform incorporation translated to a significant improvement in X‐ray CT image contrast compared with pristine fibers. Similar treatment of polypropylene pellets also enhanced the contrast of their X‐ray CT images. This is a new simple and effective method to enhance the X‐ray CT image contrast and potentially applicable to various polymer materials including polymer composites and porous polymer materials, readily allowing the observation of their 3D microstructures finely. [ABSTRACT FROM AUTHOR]

The formation of effective interphases is crucial to enable high‐performance lithium‐ion batteries. This can be facilitated by the introduction of electrolyte additives, ensuring improved stability and transport properties. The identification of proper additives requires a comprehensive understanding of the fundamental mechanisms of interfacial reactions governing interphase formation. This study presents a detailed investigation of widely known and less conventional interphase‐forming additives in high‐voltage LiNi0.6Mn0.2Co0.2O2, NMC622||artificial graphite cells. The electrochemical characterization shows that cells containing vinylethylene carbonate (VEC) significantly outperform all other investigated electrolyte formulations. Surprisingly, gas chromatography‐mass spectroscopy measurements of the electrolyte composition after cycling indicate the formation of an ineffective solid‐electrolyte interphase (SEI) in the presence of VEC. A thorough analysis of the interfacial composition via operando shell‐isolated nanoparticle‐enhanced Raman spectroscopy (SHINERS) and surface‐enhanced Raman spectroscopy elucidates rather the formation of an effective cathode‐electrolyte interphase (CEI). This phenomenon results from the reductive reaction of VEC on the anode, followed by the product transfer and electro‐polymerization of reaction products on the cathode. Additionally, focused ion beam secondary ion mass spectrometry (FIB‐SIMS) with a time of flight (ToF)‐detector is used to analyze the elemental spatial distribution of Li‐species and Mn in the respective SEIs. [ABSTRACT FROM AUTHOR]

This study is the first one that investigates in detail the bacterial intercellular response to the high density of crystallographic defects including vacancies created in Cu by high pressure torsion. To this aim, samples were deformed by high pressure torsion and afterward, their antibacterial properties against Staphylococcus aureus were analyzed in adhesion tests. As a reference an annealed sample was applied. To avoid the influence of surface roughness, specially elaborated conditions for surface preparation were employed, which do not introduce defects and assure comparable surface roughness. The analysis of the chemical composition and thickness of passive layers by X-ray photoelectron spectroscopy showed that they were comparable for nanostructured and micrograined samples, consisting of Cu2O and CuO, and a thickness of 6 nm. The interface bacterium-substrate was prepared by a focused ion beam and further analyzed by scanning transmission electron microscopy and energy dispersive spectroscopy. High pressure torsion processed Cu shows enhanced anti-adhesion properties while in contact with S. aureus than micrograined Cu. There is a linear correlation between luminous intensity and grain size−0.5. The bacterial intercellular defence mechanism includes the creation of Cu2O nanoparticles and the increased concentration of sulphur-rich compounds near these nanoparticles. [ABSTRACT FROM AUTHOR]

Pyrenoids are subcompartments of algal chloroplasts that increase the efficiency of Rubisco-driven CO 2 fixation. Diatoms fix up to 20% of global CO 2 , but their pyrenoids remain poorly characterized. Here, we used in vivo photo-crosslinking to identify pyrenoid shell (PyShell) proteins, which we localized to the pyrenoid periphery of model pennate and centric diatoms, Phaeodactylum tricornutum and Thalassiosira pseudonana. In situ cryo-electron tomography revealed that pyrenoids of both diatom species are encased in a lattice-like protein sheath. Single-particle cryo-EM yielded a 2.4-Å-resolution structure of an in vitro TpPyShell1 lattice, which showed how protein subunits interlock. T. pseudonana TpPyShell1/2 knockout mutants had no PyShell sheath, altered pyrenoid morphology, and a high-CO 2 requiring phenotype, with reduced photosynthetic efficiency and impaired growth under standard atmospheric conditions. The structure and function of the diatom PyShell provide a molecular view of how CO 2 is assimilated in the ocean, a critical ecosystem undergoing rapid change. [Display omitted] • Identification of the PyShell, a protein sheath that surrounds diatom pyrenoids • Multiscale imaging of PyShell lattices from in situ architecture to in vitro structure • PyShell knockout disrupts pyrenoid morphology and function, impairing cell growth • The PyShell is widely conserved, enabling much of the ocean's CO 2 fixation Identification and characterization of a protein lattice around the pyrenoid compartments of diatoms reveals that these prolific marine algae evolved a distinct pyrenoid architecture to promote Rubisco's CO 2 -fixing activity. [ABSTRACT FROM AUTHOR]

Recent advances in quantum technologies are highly influencing the current technological scenario. Hybrid devices combining superconductors and topological insulators represent an excellent opportunity to study the topological superconducting phase, which offers interesting features that might have significant implications in the development of quantum sensing and quantum computing. Furthermore, focused ion beam techniques, whose versatility enables to create sophisticated devices with high degree of customization, can enhance the creation of complex devices. Here, we develop a novel approach for creating single-crystal devices that is applied to the fabrication of superconducting devices based on topological insulator Bi2Se3 in a geometry characteristic of a superconducting quantum interference device. Characterization of these devices reveals that superconductivity is induced in our crystal and the supercurrent is modulated by applying an external magnetic field. These results open the way to tailoring the response of hybrid devices that combine superconductors and topological insulators by focused ion beam techniques. [ABSTRACT FROM AUTHOR]

Due to its capacity to achieve nanometre-scale machining and lithography, a focused ion beam (FIB) is an extended tool for semiconductor device fabrication and development, in particular, for diamond-based devices. However, some technological steps are still not fully optimized for its use. Indeed, ion implantation seems to affect the crystalline structure and electrical properties of diamond. For this study, a boron-doped ([B] ∼ 1017 atoms·cm−3) diamond layer grown by chemical vapour deposition was irradiated using Ga+ by FIB, with 1 nA current and 5, 20, and 30 keV of acceleration voltage. The Ga+ implanted diamond layer has been analysed through cathodoluminescence (CL) and scanning transmission electron microscopy (STEM)-related techniques. The beam penetration depth has been simulated by Monte Carlo calculations of both Ga+ (FIB) and e− (CL) beams at different energies. The comparative CL analysis of the layer as-grown and after implantation revealed peaks related to defects, such as A band, H3 centre, and defects present in the green band region. The STEM studies for the 30 keV implanted sample showed that the diamond lattice is affected by the damage, evidencing amorphisation in the layer with a sp2/sp3 ratio of 1.37, estimated by electron energy loss spectroscopy. Therefore, this study highlights the effects of the Ga+ implantation on the optical and structural characteristics of diamond, using different methods. [ABSTRACT FROM AUTHOR]

This paper presents a methodology for the physical analysis of defects on p-GaN power HEMTs that have been electrically stressed under DC surge or voltage switching stresses. The methodology includes a backside approach for sample preparation and defect localization. It is crucial to adapt the preparation process according to the position of the defect in the device structure (including metallurgy, dielectric layers, epitaxy, etc.), which depends on the type of stress applied. In our study of the reliability of the transistor under increased electrical stress in lifetime operation mode, failure analysis is used to identify the weakest areas in the design with respect to the type of stress applied. This paper presents a failure analysis consisting of techniques such as electrical characterization, photon emission microscopy and lock-in thermography for defect localization, focused ion beam slice and view, transmission electron microscopy analysis, and frontside conductive atomic force microscopy after immersion in hydrofluoric acid. [ABSTRACT FROM AUTHOR]

In this study, the interaction of pure Mg and WE43 alloy under the presence of osteoblast (OB) and osteoclast (OC) cells and their influence on the degradation of materials have been deeply analyzed. Since OB and OC interaction has an important role in bone remodeling, we examined the surface morphology and dynamic changes in the chemical composition and thickness of the corrosion layers formed on pure Mg and WE43 alloy by direct monoculture and coculture of pre-differentiated OB and OC cells in vitro. Electrochemical techniques examined the corrosion performance. The corrosion products were characterized using a combination of the focused ion beam (FIB), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). Cell viability and morphology were assessed by fluorescent microscopy and SEM. Our findings demonstrate cell spread and attachment variations, which differ depending on the Mg substrates. It was clearly shown that cell culture groups delayed degradation processes with the lowest corrosion rate observed in the presence of OBOC coculture for the WE43 substrate. Ca-P enrichment was observed in the outer-middle region of the corrosion layer but only after 7 days of OBOC coculture on WE43 and after 14 days on the pure Mg specimens. Magnesium metallic materials that can degrade over time provide distinct opportunities for orthopedic application. However, there is still a lack, especially in elucidating cell-material interface characterization. This study investigated the influence of osteoblast-osteoclast coculture in direct Mg-material contact. Our findings demonstrated that pre-differentiated osteoblasts and osteoclasts cocultured on Mg substrates influenced the chemistry of the corrosion layers. The cell spread and attachment were Mg substrate-dependent. The findings of coculturing bone cells directly on Mg materials within an in vitro model provide an effective approach for studying the dynamic degradation processes of Mg alloys while also elucidating cell behavior and their potential contribution to the degradation of these alloys. [Display omitted] [ABSTRACT FROM AUTHOR]

Venus' surface and interior dynamics remain largely unconstrained, due in great part to the major obstacles to exploration imposed by its 470°C, 90 bar surface conditions and its thick, opaque atmosphere. Flyby and orbiter‐based thermal emission data provide opportunities to characterize the surface composition of Venus. However, robust interpretations of such data depend on understanding interactions between the planet's surface basaltic rocks and its caustic carbon dioxide (CO2)‐dominant atmosphere, containing trace amounts of sulfur dioxide (SO2). Several studies, using remote sensing, thermodynamic modeling, and laboratory experiments, have placed constraints on basaltic alteration mineralogy and rates. However, constraints on the effects of SO2‐bearing reactions on basalts with diverse compositions remain incomplete. Here, we present new data from a series of gas‐solid reaction experiments, in which samples of two basalt compositions were reacted in an SO2‐bearing CO2 atmosphere, at relevant Venus temperatures, pressure, and oxygen fugacity. Reacted specimens were analyzed by scanning electron microscopy and scanning transmission electron microscopy using sample cross‐sections produced with focused ion beam milling. Surface alteration products were characterized, and their abundances estimated; subsurface cation concentrations were mapped to show the depth of alteration. We demonstrate that the initial development of reaction products progresses rapidly over the course of 30‐day runs. Alkaline basalt samples are coated by Na‐sulfate (likely thenardite, Na2SO4) and amorphous calcium carbonate (CaCO3) alteration products, and tholeiitic basalt samples are primarily covered by anhydrite (CaSO4), Fe‐oxide (FexOy: likely magnetite, Fe3O4), and other minor phases. These mineralogies differ from previous experiments in CO2‐only atmospheres. Plain Language Summary: Surface features on Venus, such as volcanic landforms, and their ages can be studied to infer the planet's interior properties. Venus' thick, opaque atmosphere and extreme temperature and pressure limit a detailed study of its surface. Fortunately, sensors aboard Venus‐orbiting spacecraft can "see" its surface using select wavelengths of light to provide opportunities to interpret the composition of its surface. However, these interpretations rely on understanding how Venus' atmosphere might chemically interact with the surface and what mineral products may result. This is not yet fully understood despite the results of several prior studies with objectives similar to ours. Here, we share the results from experiments that mimic these chemical reactions. We used rock types such as those known to be on the surface of Venus and subjected them to relevant temperatures and pressure and a blend of two reactive gases, carbon dioxide and sulfur dioxide, to model Venus' atmosphere. After the experiments, we examined the rocks with microscopic instruments that allowed us to characterize chemical changes from their surfaces to their interiors. Our interpretations suggest that these reactions occur rapidly and that the compositions of the mineral coatings produced are dictated by the rocks' slightly different compositions. Key Points: Basalts experimentally altered under Venus P‐T conditions and a CO2–SO2 atmosphere produce reaction products of Ca‐ and Na‐sulfates, and Fe‐oxidesAlteration products and the advancement of alteration were strongly dependent upon the compositions of the solid reactantsThe rates at which basalts altered in a CO2–SO2 atmosphere were greater than rates in a CO2‐only atmosphere [ABSTRACT FROM AUTHOR]

In recent years, the field of micro- and nanochannel fabrication has seen significant advancements driven by the need for precision in biomedical, environmental, and industrial applications. This review provides a comprehensive analysis of emerging fabrication technologies, including photolithography, soft lithography, 3D printing, electron-beam lithography (EBL), wet/dry etching, injection molding, focused ion beam (FIB) milling, laser micromachining, and micro-milling. Each of these methods offers unique advantages in terms of scalability, precision, and cost-effectiveness, enabling the creation of highly customized micro- and nanochannel structures. Challenges related to scalability, resolution, and the high cost of traditional techniques are addressed through innovations such as deep reactive ion etching (DRIE) and multipass micro-milling. This paper also explores the application potential of these technologies in areas such as lab-on-a-chip devices, biomedical diagnostics, and energy-efficient cooling systems. With continued research and technological refinement, these methods are poised to significantly impact the future of microfluidic and nanofluidic systems. [ABSTRACT FROM AUTHOR]

As a typical ceramic matrix composite (CMC), SiCf/SiC composite has enormous potential for application in the aerospace field because of the excellent properties such as high specific strength, high temperature resistance, oxidation resistance and good thermal shock resistance. The interphase between fiber and matrix plays a crucial role for protecting fibers, transmitting load and deflecting cracks, resulting in the pseudo-plastic fracture characteristics of SiCf/SiC composites. The design scheme of interphase significantly affects its micro structural properties, thereby affecting the macroscopic mechanical properties and damage failure modes of SiCf/SiC composites. In recent years, nano/micro fabrication techniques based on the focused ion beam (FIB) and nano/micro mechanical testing methods based on the nanoindentation are the effective methods to analyze and extract the interphase properties of SiCf/SiC composites. The existing design schemes of interphase and the influence of interphase properties on toughening mechanism are reviewed. And also the application conditions, advantages and disadvantages of small-scale mechanical testing techniques including single fiber push-out/push-in and micropillar compression are summarized. Finally, the development trend for the research of CMC interphase properties are prospected: further standardizing the testing methods, building a high-temperature testing platform and modeling of testing data. [ABSTRACT FROM AUTHOR]

High-quality superconductor/topological material heterostructures are highly desired for realisation of topological superconductivity and Majorana physics. Here, we demonstrate a method to directly draw nanoscale superconducting β-Sn patterns in the plane of a topological Dirac semimetal (TDS) α-Sn thin film by irradiating a focused ion beam and taking advantage of the heat-driven phase transition of α-Sn into superconducting β-Sn. The β-Sn nanowires embedded in a TDS α-Sn thin film exhibit a large superconducting diode effect (SDE), whose rectification ratio η reaches a maximum of 35% when the magnetic field is applied parallel to the current. The results suggest that the SDE may occur at the α-Sn/β-Sn interfaces where the TDS α-Sn becomes superconducting by a proximity effect. Our work thus provides a universal platform for investigating quantum physics and devices based on topological superconducting circuits of any shape. Topological superconductivity may have important implications for fault-tolerant quantum computing, but its practical implementation remains challenging. Here, the authors report the fabrication of nanoscale heterojunctions based on superconducting β-Sn and topological Dirac semimetal α-Sn, showing superconducting diode rectification ratios up to 35%. [ABSTRACT FROM AUTHOR]

Biological channels, especially membrane proteins, play a crucial role in metabolism, facilitating the transport of nutrients and other materials across cell membranes in a bio‐electrolyte environment. Artificial nanopores are employed to study ion and biomolecule transport behavior inside. While the non‐specific interaction between the nanopore surface and transport targets has garnered significant attention, the impact of surface roughness is overlooked. In this study, Nanopores with different levels of inner surface roughness is created by adjusting the FIB (Focus Ion Beam) fabrication parameters. Experiments and molecular dynamics (MD) simulations are employed to demonstrate that greater roughness results from larger FIB beam currents and shorter processing times. Lower roughness increases the capture rate of biomolecules, while greater roughness enhances the normalized blockade current (ΔI/I0). The phenomenon of rougher nanopores are attributed to a barrier‐dominated capture mechanism and more likely to induce DNA folding. This transport barrier exists in rough nanopores by utilizing steer molecular dynamics (SMD) simulations to investigate the force profile of a dA10 DNA molecule during translocation is demonstrated. This work illustrates how surface roughness influences the ionic current features and the translocation of biomolecules, paving a new way for tunning the molecule transport in nanopores. [ABSTRACT FROM AUTHOR]

A streamlined sample preparation method for nanomechanical testing is needed to improve the quality of specimens, reduce the cost, and increase the versatility of specimen fabrication. This work outlines an in-plane liftout focused ion beam (FIB) fabrication procedure to prepare electron-transparent specimens for in situ transmission electron microscopy (TEM) nanomechanical testing. Ion etching and electron backscatter diffraction (EBSD) techniques were used to lift out a [110] oriented grain from a neutron-irradiated bulk X-750 alloy. Careful control of voltages and currents ensured precision. Top surface thinning sweeps prevented resurfacing and redeposition while dog-bone geometries were shaped with a 1:4 gauge width-to-milling pattern diameter ratio. Nanotensile testing in the TEM with a picoindenter allowed for the estimation of an ultimate tensile strength of 2.41 GPa, and inspection revealed a high density of bubbles in the X-750 matrix. The proposed fabrication procedure is significant for preparing samples from radioactive materials, studying complex structures that are orientation-dependent, and analyzing desired planar areas. [ABSTRACT FROM AUTHOR]

Polycrystalline silicon carbide (SiC) is a highly valuable material with crucial applications across various industries. Despite its benefits, processing this brittle material efficiently and with high quality presents significant challenges. A thorough understanding of the mechanisms involved in processing and removing SiC is essential for optimizing its production. In this study, we investigated the sawing characteristics and material removal mechanisms of polycrystalline silicon carbide (SiC) ceramic using a diamond wire saw. Experiments were conducted with high wire speeds of 30 m/s and a maximum feed rate of 2.0 mm/min. The coarseness value (Ra) increased slightly with the feed rate. Changes in the diamond wire during the grinding process and their effects on the grinding surface were analyzed using scanning electron microscopy (SEM), laser confocal microscopy, and focused ion beam (FIB)-transmission electron microscopy (TEM). The findings provide insights into the grinding mechanisms. The presence of ductile grinding zones and brittle fracture areas on the ground surface reveals that external forces induce dislocation and amorphization within the grain structure, which are key factors in material removal during grinding. [ABSTRACT FROM AUTHOR]

The curtaining effect is a common challenge in focused ion beam (FIB) surface preparation. This study investigates methods to reduce this effect during plasma FIB milling of Inconel 718 (nickel‐based superalloy). Platinum deposition, silicon mask and XeF2 gas injection were explored as potential solutions. These methods were evaluated for two ion beam current conditions; a high ion beam intensity condition (30 kV–1 µA) and a medium one (30 kV–100 nA) and their impact on curtaining reduction and resulting cross‐section quality was assessed quantitatively thanks to topographic measurements done by atomic force microscopy (AFM). XeF2 assistance notably improved cross‐section quality at medium current level. Pt deposition and Si mask individually mitigated the curtaining effect, with greater efficacy at 100 nA. Both methods also contributed to reducing cross‐section curvature, with the Si mask outperforming Pt deposition. However, combining Pt deposition and Si mask with XeF2 injection led to deterioration of these protective layers and the reappearance of the curtaining effect after a quite short exposure time. LAY DESCRIPTION: The so‐called curtaining effect is a common challenge in focused ion beam (FIB) surface preparation. It is characterised by a relief occurring on the FIB prepared surface whereas a perfectly flat surface would ideally be expected. The issue of FIB‐induced curtaining effect represents a significant challenge in large‐scale 3D analysis applications, notably in methodologies reliant on FIB serial sectioning, such as 3D electron backscatter diffraction (3D EBSD). A strong curtaining effect can alter data quality and so their interpretation after 3D reconstruction. This study investigates methods to reduce this effect during plasma FIB milling of Inconel 718 (nickel‐based superalloy). Platinum deposition, silicon mask and XeF2 gas injection were explored as potential solutions. These methods were evaluated for two ion beam current conditions: a high ion beam intensity condition (30 kV–1 µA) and a medium one (30 kV–100 nA) and their impact on curtaining reduction, and resulting cross‐section quality was assessed quantitatively thanks to topographic measurements done by atomic force microscopy (AFM). XeF2 assistance notably improved cross‐section quality at medium current level. Pt deposition and Si mask individually mitigated the curtaining effect, with greater efficacy at 100 nA. Both methods also contributed to reducing cross‐section curvature, with the Si mask outperforming Pt deposition. However, combining Pt deposition and Si mask with XeF2 injection led to deterioration of these protective layers and the reappearance of the curtaining effect after a quite short exposure time. [ABSTRACT FROM AUTHOR]

By analyzing the chromaticity values of the ancient blue-and-white porcelain combined with the imitated experiment, the color information is quantified and 'color dispersion' mechanism is clarified. Energy Dispersive X-Ray Fluorescence (EDXRF), field emission scanning electron microscopy (FE-SEM), the advanced focused ion beam transmission electron microscopy (FIB-TEM) technique, etc, were used to study the characteristics and the 'color dispersion' mechanism of the blue-and-white porcelain in Jingdezhen imperial kiln. The 'color dispersion' of the blue-and-white porcelain is mainly caused by Co-element structure stability, which is verified by the archaeological experiment results. Blue-and-white decoration lines diffusion length (named as 'color dispersion') are long (i.e. fuzzy) which has few or no spinel crystals in the body-glaze interaction layer of the blue-and-white porcelain. However, the blue and white porcelain with the clear lines has a large number of spinel crystals. The experimental results enrich the literature on the history of ceramic manufacturing techniques in Jingdezhen. [ABSTRACT FROM AUTHOR]

Collagen-based hydrogels are commonly used in mechanobiology to mimic the extracellular matrix. A quantitative analysis of the influence of collagen concentration and properties on the structure and mechanics of the hydrogels is essential for tailored design adjustments for specific in vitro conditions. We combined focused ion beam scanning electron microscopy and rheology to provide a detailed quantitative atlas of the mechanical and nanoscale three-dimensional structural alterations that occur when manipulating different hydrogel's physicochemistry. Moreover, we study the effects of such alterations on the phenotype of breast cancer cells and their mechanical interactions with the extracellular matrix. Regardless of the microenvironment's pore size, porosity or mechanical properties, cancer cells are able to reach a stable mesenchymal-like morphology. Additionally, employing 3D traction force microscopy, a positive correlation between cellular tractions and ECM mechanics is observed up to a critical threshold, beyond which tractions plateau. This suggests that cancer cells in a stable mesenchymal state calibrate their mechanical interactions with the ECM to keep their migration and invasiveness capacities unaltered. The paper presents a thorough study on the mechanical microenvironment in breast cancer cells during their interaction with collagen based hydrogels of different compositions. The hydrogels' microstructure were obtained using state-of-the-art 3D microscopy, namely focused ion beam-scanning electron microscope (FIB-SEM). FIB-SEM was originally applied in this work to reconstruct complex fibered collagen microstructures within the nanometer range, to obtain key microarchitectural parameters. The mechanical microenvironment of cells was recovered using Traction Force Microscopy (TFM). The obtained results suggest that cells calibrate tractions such that they depend on mechanical, microstructural and physicochemical characteristics of the hydrogels, hence revealing a steric hindrance. We hypothesize that cancer cells studied in this paper tune their mechanical state to keep their migration and invasiveness capacities unaltered. [Display omitted] [ABSTRACT FROM AUTHOR]

Nanogrooves with high aspect ratios possess small size effects and high-precision optical control capabilities, as well as high specific surface area and catalytic performance, demonstrating significant application value in the fields of optics, semiconductor processes, and biosensing. However, existing manufacturing methods face issues such as complexity, high costs, low efficiency, and low precision, especially in the difficulty of fabricating nanogrooves with high resolution on the nanoscale. This study proposes a method based on focused ion beam technology and a layer-by-layer etching process, successfully preparing V-shaped and rectangular nanogrooves on a silicon dioxide substrate. Combining with cellular automaton algorithm, the ion sputtering flux and redeposition model was simulated. By converting three-dimensional grooves to discrete rectangular slices through a continuous etching process and utilizing the sputtering and redeposition effects of gallium ion beams, high-aspect-ratio V-shaped grooves with up to 9.6:1 and rectangular grooves with nearly vertical sidewalls were achieved. In addition, the morphology and composition of the V-shaped groove sidewall were analyzed in detail using transmission electron microscopy (TEM) and tomography techniques. The influence of the etching process parameters (ion current, dwell time, scan times, and pixel overlap ratio) on groove size was analyzed, and the optimized process parameters were obtained. [ABSTRACT FROM AUTHOR]

In this paper, we describe the fracture mechanisms of lead zirconate titanate (PZT) piezoelectric thin films synthesized by sol-gel processing. One of the technical concerns in piezoelectric thin films is how their surface fractures because, in most cases, the films fail electrically, and the fracture surface is remade after its first fracture. To estimate the failure mechanisms, cantilever-type and clamped capacitor-type actuators made of PZT piezoelectric thin films deposited on a Si wafer were prepared and subjected to electrical and mechanical stresses. The cantilever-type actuators showed a decreasing trend in dielectric withstand voltage with increasing number of mechanical loading cycles. The clamped capacitor-type actuators showed a decreasing trend in withstand voltage with increasing cyclic voltage amplitude. Through mechanical and electrical experiments, we found that the origin of cracking differed from that of short circuit. This finding indicates that the PZT films fractured mechanically, then fractured electrically. The focused ion beam fabrication of a surface defect and scanning electron microscopy observation around the defect suggest a reasonable fracture mechanism. [ABSTRACT FROM AUTHOR]

In this paper, we describe the mechanical characteristics of Al2O3 and TiCN thin films formed by chemical vapor deposition (CVD) and a TiAlN thin film formed by physical vapor deposition (PVD), which are used as hard coating films. A focused ion beam (FIB) was used to fabricate a microcantilever beam for strength tests and fracture toughness tests under bending. A nanoindentation system was used to apply normal force to cantilever beams. All the films showed a linear force–deflection relationship, indicating brittle fracture during elastic deformation. The Young’s modulus ranged from 340 to 379 GPa, with no significant difference among the films, whereas the fracture strength of the Al2O3 films was 5.5 GPa, which was almost twice those of the other two films. For the fracture toughness test, a precrack with various depths was made using FIB at 2 μm from the fixed end of the cantilever beam. The Al2O3 film toughness values ranged from 4.1 to 5.5 MPa√m, which were almost twice that of the TiCN film at each precrack depth. Both CVD films showed a similar trend, i.e., an increase in fracture toughness with decreasing precrack depth, However, the fracture toughness of the TiAlN film showed no precrack depth dependence. The difference in fracture toughness between the CVD and PVD films is discussed on the basis of fracture surface observation results and information on the crystal grain size and orientation. [ABSTRACT FROM AUTHOR]

A multifunctional nanostructured hybrid composed of metal–protein–ceramic was designed and then synthesized using three different methods: chemical reduction, physical adsorption, and coprecipitation. The processes yielded colloidal spherical silver nanoparticles (AgNPs) enveloped in a bovine serum albumin (BSA) corona, leading to the core–shell structure AgNPs–BSA. To enhance biocompatibility and mitigate potential toxicity associated with metallic nanoparticles, this core–shell structure was coated with a layer of calcium carbonate (CaCO3). In order to analyze the internal structure of the resulting hybrid nanostructure (AgNPs–BSA–CaCO3), a number of samples were produced by focused ion beam (FIB) and characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and zeta potential (ζ) measurements. The cytotoxic effect of the samples were evaluated through in vitro tests on mouse macrophage cell line RAW 264.7 ATCC TIB‐71, this was accomplished by calculating the appropriate concentrations from the dose–response curve of AgNPs. Research showed that the AgNPs–BSA–CaCO3 mixture triggered the formation of vaterite; these findings were corroborated by FTIR and Raman techniques. The spherical nanostructures have an average diameter size of 4.3 ± 2 μm and an average roughness (Ra) of 3.11 ± 0.62 μm. Zeta potential (ζ) and isoelectric point studies reveal that this hybrid nanostructure exhibits amphoteric behavior that differs from either AgNPs or AgNPs–BSA alone. Cell viability response exceeded 75%, indicating the noncytotoxic nature of the proposed hybrid nanostructures. [ABSTRACT FROM AUTHOR]

A multifunctional nanostructured hybrid composed of metal–protein–ceramic was designed and then synthesized using three different methods: chemical reduction, physical adsorption, and coprecipitation. The processes yielded colloidal spherical silver nanoparticles (AgNPs) enveloped in a bovine serum albumin (BSA) corona, leading to the core–shell structure AgNPs–BSA. To enhance biocompatibility and mitigate potential toxicity associated with metallic nanoparticles, this core–shell structure was coated with a layer of calcium carbonate (CaCO3). In order to analyze the internal structure of the resulting hybrid nanostructure (AgNPs–BSA–CaCO3), a number of samples were produced by focused ion beam (FIB) and characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and zeta potential (ζ) measurements. The cytotoxic effect of the samples were evaluated through in vitro tests on mouse macrophage cell line RAW 264.7 ATCC TIB‐71, this was accomplished by calculating the appropriate concentrations from the dose–response curve of AgNPs. Research showed that the AgNPs–BSA–CaCO3 mixture triggered the formation of vaterite; these findings were corroborated by FTIR and Raman techniques. The spherical nanostructures have an average diameter size of 4.3 ± 2 μm and an average roughness (Ra) of 3.11 ± 0.62 μm. Zeta potential (ζ) and isoelectric point studies reveal that this hybrid nanostructure exhibits amphoteric behavior that differs from either AgNPs or AgNPs–BSA alone. Cell viability response exceeded 75%, indicating the noncytotoxic nature of the proposed hybrid nanostructures. [ABSTRACT FROM AUTHOR]

In this study, the formation of nano-porous/fibrous structures was investigated by spot-ion irradiation on Ge and GaSb substrates to consider the formation range of nanostructures and point defects. Spot-ion irradiation was performed in a focused ion beam system with a beam diameter of 35.1 nm, which is determined by the system. The fluence and ion beam current ranged within 5 × 1019–1 × 1022 ions/m2 and 500–520 pA, respectively. All the irradiated ions were Ga+ with incident energy adjusted at 30 keV, and the angle of incidence to the surface normal was 0°. The interval of the irradiated spot ranged from 100 to 1000 nm. For line-patterned irradiations, these spots overlapped with one another at an overlap ratio of 50%, producing a 35.1 nm × 10 μm irradiated region. Result shows that nanostructured regions followed a spot interval. When an interval was shorter than 200 nm, each nanostructured spot coalesced with neighbors to form large and uniform structures. Furthermore, line-patterned irradiation indicated that the migration distance of vacancy was ∼300 nm at maximum, which is consistent with the coalescence phenomenon. [ABSTRACT FROM AUTHOR]

We report on the metrological characterization of the emission from a germanium-vacancy center in diamond under a microfabricated solid immersion lens in a confocal laser-scanning microscope setup. Ge ions were implanted into a synthetic diamond at 3 MeV, and germanium-vacancy centers were then formed by subsequent annealing. Afterward, solid immersion lenses were fabricated in a focused ion beam scanning electron microscope. The photoluminescence was investigated at room temperature in terms of the spectral distribution, the excited state lifetime, the second-order correlation function, and the saturation behavior, proving simultaneous high single-photon purity and high brightness. Two methods were exploited to minimize the residual multi-photon probability: spectral filtering and temporal filtering. According to these results, we assume that Raman scattered photons and emission from neighboring color centers play an important role in the residual multi-photon emission probability. The system efficiency of the single-photon source was investigated and found to be in accordance with the value calculated from all sources of loss in the setup. The branching ratio of the germanium-vacancy center for the decay into the ground state and into metastable state was calculated. The results enable the usage of the single-photon source in future quantum radiometric experiments. [ABSTRACT FROM AUTHOR]

Purpose: To investigate microtensile bond strength and characterization with the novel lithium disilicate coating technique compared to conventional air abrasion. Materials and Methods: Eight zirconia blocks were fabricated and assigned to two groups (n = 4 each): (1) Lithium disilicate coating followed by hydrofluoric acid etching and Monobond N Primer (LiDi group); and (2) alumina air abrasion (MUL group). For each group, two identically pretreated zirconia blocks were bonded together with Multilink Speed Cement and cut into 30 stick-shaped specimens (1 × 1 × 9 mm3). The 120 specimens were stored in water for 24 hours and assigned to one of three groups (n = 20/group): (1) short-term storage for 24 hours; (2) thermocycling for 5,000 cycles; and (3) thermocycling for 10,000 cycles. A microtensile bond strength test was performed and evaluated. The bond strength results were analyzed using two-way ANOVA followed by one-way ANOVA and Tukey HSD (a = .05). Energy-dispersive x-ray spectroscopy (EDS), Fourier-transform infrared (FTIR), x-ray diffraction (XRD), focused ion beam scanning electron microscopy (FIB-SEM), and scanning electron microscopy (SEM) were used for chemical, crystalline phase, and failure mode analyses. Results: The MUL groups recorded higher bond strength than the LiDi groups. Thermocycling significantly decreased the bond strength in both groups. Chemical analyses suggested that the lithium disilicate layer underwent hydrolysis, which compromised long-term bond strength. Conclusion: The bond between composite cement and alumina-abraded zirconia performed better than that with the lithium disilicate coating technique. [ABSTRACT FROM AUTHOR]

Bone has a complex hierarchical structure with structural integration from nm to cm. The understanding of bone structure is developing rapidly due to improvements in available methodologies that allow unravelling structures across several length scales. These methods include advances in electron microscopy, in particular, focused ion beam scanning electron microscopy (FIB‐SEM), confocal laser scanning microscopy techniques, X‐ray imaging, X‐ray diffraction tomography (XRD‐CT), and tensor tomography (small angle X‐ray scattering tensor tomgraphy, SAXS‐TT and wide angle X‐ray scattering tensor tomgraphy, WAXS‐TT). Special emphasis is placed on the latter X‐ray techniques that are emerging into powerful tools. Through a review of selected recent results on the structure of the bone matrix as well as the lacuno‐canalicular network housing the osteocyte cells of bone, it is proposed that bone is more heterogeneous than typically described and that local variation in composition and crystallography may play a significant role in bone biology in health and disease. [ABSTRACT FROM AUTHOR]

Structural color originates from the interference of light with periodic structures that feature characteristic length scales on the order of the wavelength of visible light. Long‐range order in photonic structures usually causes iridescence, and increasing disorder renders colors angle‐independent. Random disorder distributes scattering intensity over all wavelengths, producing white in the absence of absorption. Various non‐iridescent, vivid color patterns are found in Sternotomini longhorn beetles. Herein, Sternotomis virescens is investigated, where elytral scales produce a green‐blue color pattern on otherwise black elytra. Combining focused ion beam scanning electron microscopy (FIB‐SEM) tomography, ultra‐small‐angle X‐ray scattering (USAXS), structural modeling, and full‐wave optical simulations, it is found that the color originates from amorphous photonic networks based on sub‐units resembling the I‐WP unit cell, a triply‐periodic minimal surface with body‐centered‐cubic symmetry. This work provides insights into how quasi‐order produces stable colors in S. virescens longhorn beetles, highlights the advantages of volumetric imaging using FIB‐SEM tomography of porous nanostructured materials, and raises interesting questions about the formation mechanisms of amorphous structures in vivo. [ABSTRACT FROM AUTHOR]

Hierarchical porous acrylate‐based materials are highly interesting as 3D filter materials, such as for virus removal from suspensions. Here, the synthesis of highly porous monolithic 3D materials by polymerization‐induced phase separation in liquid crystal display (LCD) based 3D printing is presented for the efficient removal of human adenovirus type 5. The hierarchical porosity can be tuned via the variation of the photocurable resin composition (i.e., inherent porosity) and the computer‐aided design (i.e., “printed” porosity; microchannels). 3D polymer structures with highly intricate geometries and structural features ranging from ≈20 nm up to cm can be achieved, which can be used for effective virus removal in a laboratory‐scale flow‐through approach. Combined focused ion beam/scanning electron microscopy tomography and mercury porosimetry provide detailed information on the inherent pore size, pore size distribution, and pore interconnectivity, which is key for the performance of such functional 3D materials. Polymers with a theoretical void volume of 75% show virus capture with a removal efficiency of ≈70% of the adenovirus. Polymers with the same theoretical void volume and macroscopic design but a more hydrophobic nature captured only ≈33%. An optimized adenovirus retention of 98% is achieved by adjusting the microchannels of the tunable inserts. [ABSTRACT FROM AUTHOR]

Cathodic protection is widely employed to prevent the corrosion of steel in marine environments. However, an inappropriate cathodic potential may lead to the generation of hydrogen and consequently induce cracking. Therefore, this study investigates the relationships between cathodic deposition potential, calcareous deposits, hydrogen evolution, and hydrogen permeation. Combining scanning electron microscopy, Raman spectroscopy, coupled focused ion beam lithography, and energy dispersive X-ray spectroscopy, it is observed that all calcareous deposits formed in artificial seawater at the potential range of −1.0 to −1.3 V SCE have calcium-rich inner and magnesium-rich outer layers, respectively. The thickness and compactness of each layer of the double-layer deposits vary with the cathodic deposition potential. Combining potentiodynamic polarization, hydrogen permeation experiments, and the morphology of calcareous deposits, we can find that the deposits formed at the cathodic deposition potential of −1.1 V SCE exhibit a thin inner layer and a condensed outer layer, which is effective in balancing hydrogen recombination and absorption, thus, inhibiting hydrogen entry. This study provides guidelines for the cathodic protection of steel materials in marine environments. • Addresses hydrogen-induced cracking in cathodic-protected steel in seawater. • Studies the correlation between cathodic potential and calcareous deposits in steel. • Q460 Steel specimens were applied with a potential in the range −1.0 to −1.3 V SCE. • Double-layer deposits with Ca- and Mg-rich inner and outer layers, respectively. • Deposits under −1.1 V SCE are most effective in preventing hydrogen permeation. [ABSTRACT FROM AUTHOR]

In this study, the occurrence state and distribution characteristics of gallium (Ga) in zinc refinery residue were investigated by dilute acid pre-washing to enrich Ga in zinc refinery residue, followed by silane coupling agent pretreatment and epoxy resin curing, and then analyzed using scanning electron microscopy, focused ion beam micro-slicing technique and transmission electron microscopy. The acid washing increased the mass ratio of Ga from 0.92% to 2.12%. Energy-dispersive spectroscopy and select area electron diffraction revealed that Ga occurred as tiny ring-like particles of gallobeudantite (a Pb-jarosite) that intimately envelop the previously formed K-jarosite fine-grained inclusions. Density functional theory calculations showed that the interplanar spacings of the new phase formed after Ga substitution for Fe in Pb-jarosite (3.413 Å and 5.505 Å) were in good agreement with the actual measured values, further confirming that Ga substitution for Fe in Pb-jarosite was achieved. The kinetical model explains the formation of multiple phases during precipitation in the treatment of zinc leaching solution. Compared to existing studies, this work reveals the spatial distribution of gallium with higher resolution and jointly determines the gallium-containing phases through experimental analysis and simulation calculations. This microanalytical method enhances the understanding of Ga species formation during zinc refining, aiding in their distribution control and process optimization. [ABSTRACT FROM AUTHOR]