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Scuffing, a type of wear found in highly stressed or poorly lubricated contacts, is characterized by a rapid increase in friction and severe plastic deformation of the near-surface material. Scuffing has proven difficult to study because it initiates unpredictably, progresses rapidly, and typically develops within an inaccessible contact interface. Although there have been successful in-situ studies of scuffing in real-time, the transparent counter body needed for these studies changes the interactions between the surfaces and the lubricant, which affects the scuffing process in unknown ways. This paper describes the development of X-ray-compatible tribometry to study the scuffing of self-mated steels in-situ and in real-time. The method uses a crossed cylinders configuration with a thin (500 μm thick) stationary component and a small (≈200 μm) contact width to maximize X-ray interactions with atoms within the stress field generated by the contact. The resulting instrument and method are used to benchmark the scuffing response of self-mated 52,100 steel under tribologically challenging ‘oil-off’ lubrication conditions. The results demonstrate reliable scuffing in this configuration despite the relatively small contact areas and loads used. Following scuffing, gross plastic deformation was observed on both surfaces along with significant subsurface grain refinement and flow only on the stationary surface, which experienced constant contact. Interestingly, high friction initiated at specific locations of the migratory surface, which experienced intermittent contact, and then propagated across the track over time, suggesting that local conditions of the migratory surface dominated friction leading into the failure event. [ABSTRACT FROM AUTHOR]

High entropy alloys have emerged recently as promising candidates for high-temperature applications. This study explores the detailed oxidation behavior of CoCrFeMnNi alloy by using a combination of in-situ, short-duration and long-duration high-temperature exposure up to 1000 ⁰C. The study reveals Cr and Mn played a significant role in the oxidation/passivation of the alloy. It was found that Cr enhanced the oxidation resistance, especially by limiting oxygen diffusion and was quite effective up to 600 ⁰C. However, at higher temperatures, Mn continuously diffuses towards the surface and forms a poorly adherering oxide scale. Study on CoCrFeNi and CoFeMnNi alloys to investigate the roles of Cr and Mn individually revealed that under similar conditions, CoCrFeNi had a relatively continuous and less spalled oxide layer with better adherence to the alloy compared to cantor alloy. However, compared to Cr-containing alloys, the CoFeMnNi alloy did not have a continuous, well-adhering, non-protective oxide layer making the alloy prone to severe and faster oxidation. Same was apparent from significant internal oxidation, the appearance of massive cracks, and voids. Before and after the oxidation, CoCrFeMnNi and CoCrFeNi were single-phase fcc structures while CoFeMnNi decomposed into a two-phase alloy due to significant uptake of oxygen. Prolonged oxidation and molten-state studies revealed that the oxidation behaviour of HEAs is a thermodynamic-driven process, and CoCrFeMnNi is expected to gradually lose Mn to surface oxide followed by migration of Co, Ni and Fe, which otherwise hardly migrated or participated in the oxidation process. High-temperature heat treatment in vacuum confirmed that the migration to the surface was driven by its oxidation at the surface. [ABSTRACT FROM AUTHOR]

The structure of a nanocatalyst during electrocatalytic reactions often deviates from its pristine structure due to intrinsic properties, or physical and chemical adsorption at the catalytic surfaces. Taking Cu-based catalysts for CO2 electroreduction reactions (CO2RR) as an example, they often experience segregation, leaching, and alloying during reactions. With the recent breakthrough development of high-resolution polymer electrochemical liquid cells, in-situ electrochemical liquid cell transmission electron microscopy (EC-TEM) alongside other advanced microscopy techniques, has become a powerful platform for revealing electrocatalysts restructuring at the atomic level. Considering the complex reactions involving electrified solid-liquid interfaces and catalyst structural evolution with intermediates, systematic studies with multimodal approaches are crucial. In this article, we demonstrate a research protocol for the study of electrocatalysts structural evolution during reactions using the in-situ EC-TEM platform. Using Cu and CuAg nanowire catalysts for CO2RR as model systems, we describe the experimental procedures and findings. We highlight the platform's crucial role in elucidating atomic-scale pathways of nanocatalyst restructuring and identifying catalytic active sites, as well as avoiding potential artifacts to ensure unbiased conclusions. Using the multimodal characterization toolbox, we provide the opportunity to correlate the structure of a working catalyst with its performance. Finally, we discuss advancements as well as the remaining gap in elucidating the structural-performance relationship of working catalysts. We expect this article will assist in establishing guidelines for future investigations of complex electrochemical reactions, such as CO₂RR and other catalytic processes, using the in-situ EC-TEM platform. [ABSTRACT FROM AUTHOR]

Automation of synchrotron radiation powder diffraction experiments at SPring-8 is described, focusing on the BL02B2 powder diffractometer and the BL13XU high-resolution instrument. The development of automation, including data acquisition, sample exchange, and instrument switching, has greatly improved experimental efficiency; the integration of the MYTHEN detector and automated systems for temperature control, sample preparation, and gas handling has improved measurement speed and accuracy. These developments enable high-throughput, in-situ, and operando measurements that support further materials innovation and facilitate the application of data-driven analysis to large experimental data sets. [ABSTRACT FROM AUTHOR]

[Display omitted] Acoustic levitation is a suitable approach for studying processes occurring at the gas–liquid interfaces, as it allows its investigation in a contact-free manner while providing control over the gas phase. Here, we hypothesize that phase transitions induced by a CO 2 rich atmosphere can be examined, at different length scales, in a contact-free manner. A system consisting of 12-hydroxysteric acid (HSA) soaps mixed with different ratios of monoethanolamine (MEA) and choline hydroxide, was prepared. Microliter droplets of the samples were acoustically levitated and monitored with a camera, while exposed to CO 2 to modify the pH through diffusion at the air–liquid interface and inside the droplet. The phase transition and water mobility in the levitated droplets were evaluated through X-ray scattering (SAXS/WAXS) and magnetic resonance studies, in real-time. Finally, the droplets were collected and examined under the microscope. The introduction of CO 2 gas induced a phase transition from micelles to multi-lamellar tubes, resulting in a gel-like behavior both in the bulk and at the interface. The high stability of the acoustic levitator allowed the investigation of this dynamic phenomenon, in real-time, in a contact-free environment. This study showcases the suitability of acoustic levitation as a tool to investigate complex chemical processes at interfaces. [ABSTRACT FROM AUTHOR]

Methods and procedures for measuring greenhouse gases vary in different aspects, which could dictate most of the decisions. Even within the same context of measurements, there are different techniques and procedures. This study presents a harmonized approach so that results from different studies are easily compared, and methods can be reproduced. The relevant literature on sampling has been discussed and used to establish consistency. The applied knowledge acquired during the two related field experiments, 2017-2018 and 2018-2019, has also been used to leverage the procedures. It was observed that the non-flow-through steady-state (closed or static chamber) method is the widely used method in the field for greenhouse gas measurements. Its chronological sampling's main steps are anchor installation, upper part chamber placement, temperature recording, gas sample withdrawal, injecting the sample into the vial, flushing the syringe with air twice, upper chamber part removal from the anchor, and placement on the plot border beside the respective anchors. These leveraged procedures can ensure consistency in acquiring data for reliable results to help make informed decisions about greenhouse gas reductions. [ABSTRACT FROM AUTHOR]

Intrahospital transport of critically ill patients for diagnostic or therapeutic procedures can be compromised by patient instability, equipment problems or inexperienced teamworking. This quasi-experimental study aimed to assess the effectiveness of an in-situ interprofessional simulation-based training (IIST) model for junior member transport teams. Newly registered postgraduate physicians, nurses and respiratory therapists underwent the IIST. The technical skills (TS) of each participant and non-technical skills (NTS) of each interprofessional team were assessed using well-validated checklists. Thirty-six participants enrolled and were randomly assigned to six experimental and six control teams. Most participants achieved a significantly higher level of both TS and NTS. Both the control and experimental teams overvalued their NTS in the pretest, while the posttest self-assessment scores among the experimental groups more closely matched the expert assessments. Despite challenges in scheduling and the setting, the IIST was successfully conducted in a crowded hospital, which enabled trainees to optimize their learning in a real-life environment. In conclusion, the IIST model can facilitate the development of both TS and NTS for transport team members. Transport teams made up of newly registered staff from different disciplines may lack insight into their NTS in critical patient transfer management, but simulation training may cause improvements. [ABSTRACT FROM AUTHOR]

The sensitivity of grain boundary (GB) cracks often limits the high-temperature plasticity of superalloys. The 750 ℃ tensile deformation of fine-grained Ni-Co based wrought superalloys was observed in situ using a scanning electron microscope (SEM) equipped with an electron backscatter diffraction (EBSD) probe to clarify the texture formation and GB response. The GB stress concentration depends on the grain orientation and slip system alignment on both sides. This reflects the ability of GBs to cope with deformation incompatibility. This study provides valuable insights for predicting the failure of polycrystalline superalloys and offers new ideas for microstructure evaluation and GB design.