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We report in this article a detailed study on how to stabilize a first-row transition metal (M) in an intermetallic L10-MPt alloy nanoparticle (NP) structure and how to surround the L10-MPt with an atomic layer of Pt to enhance the electrocatalysis of Pt for oxygen reduction reaction (ORR) in fuel cell operation conditions. Using 8 nm FePt NPs as an example, we demonstrate that Fe can be stabilized more efficiently in a core/shell structured L10-FePt/ Pt with a 5 À Pt shell. The presence of Fe in the alloy core induces the desired compression of the thin Pt shell, especially the two atomic layers of Pt shell, further improving the ORR catalysis. This leads to much enhanced Pt catalysis for ORR in 0.1 M HClO4 solution (at both room temperature and 60 °C) and in the membrane electrode assembly (MEA) at 80 °C. The L10-FePt/Pt catalyst has a mass activity of 0.7 A/mgPt from the half-cell ORR test and shows no obvious mass activity loss after 30 000 potential cycles between 0.6 and 0.95 V at 80 °C in the MEA, meeting the DOE 2020 target (<40% loss in mass activity). We are extending the concept and preparing other L10-MPt/Pt NPs, such as L10-CoPt/Pt NPs, with reduced NP size as a highly efficient ORR catalyst for automotive fuel cell applications. [ABSTRACT FROM AUTHOR]

We report a facile method for assembly of a monolayer array of nitrogen-doped graphene (NG) and nanoparticles (NPs) and the subsequent transfer of two layers onto a solid substrate (S). Using 3 nm NiPd NPs as an example, we demonstrate that NiPd-NG-Si (Si=silicon wafer) can function as a catalyst and show maximum NiPd catalysis for the hydrolysis of ammonia borane (H3NBH3, AB) with a turnover frequency (TOF) of 4896.8 h−1 and an activation energy ( Ea) of 18.8 kJ mol−1. The NiPd-NG-S catalyst is also highly active for catalyzing the transfer hydrogenation from AB to nitro compounds, leading to the green synthesis of quinazolines in water. Our assembly method can be extended to other graphene and NP catalyst materials, providing a new 2D NP catalyst platform for catalyzing multiple reactions in one pot with maximum efficiency. [ABSTRACT FROM AUTHOR]

A novel 3D digital image correlation (DIC) system based on a single three charge-couple device (3CCD) color camera is proposed in this paper. Images from three different perspectives are captured by a 3CCD camera using a reflective-based pseudo-vision system. These images are then separated by the different CCD channels, and the correlation algorithm for the multi-camera DIC system is adopted to evaluate the images. Compared to the conventional multi-camera DIC system, the proposed system is much more compact. In addition, the proposed system has no loss of spatial resolution, compares to the traditional single camera DIC system. The complex surface measurement ability and the measurement accuracy is significantly improved through the use of the multi-camera DIC algorithm. The principle of the proposed system is described in detail as well as the experimental setup. A series of validation tests are performed, and the results are verified with the commercial 3D-DIC system. [ABSTRACT FROM AUTHOR]

This article shows an experimental validation of the volume conservation assumption (zero plastic volume change assumption) for aluminum alloy (AA6000) sheet metal. A series of tensile tests were conducted. During the tensile tests, an optimized digital image correlation setup was used to simultaneously measure three principal strain components. The experimental results show that, at locations outside the necking band, AA6000 strictly follows the zero plastic volume change assumption throughout the duration of the test. Inside the necking band, AA6000 follows the zero plastic volume change assumption in the elastic range and early plastic range. However, before failure, a visible volume strain increase can be found inside the necking band, which shows that, in the deep plastic zone, AA6000 does not always follow the volume conservation assumption. The experiment plan, measurement setup optimization, experimental results and data analysis are shown in detail. [ABSTRACT FROM AUTHOR]

A comprehensive strategy has been developed to synthesize highly ordered mesoporous Nafion membranes with different structure symmetries including 2D hexagonal (2D-H), 3D face-centered (3D-FC), 3D cubic-bicontinuous (3D-CB) and 3D body-centered (3D-BC), using a soft template method with the assistance of a silica colloidal mediator. The Nafion membrane derived from the self-assembled mesoporous Nafion–silica composites maintained the microstructures of the silica framework, which was confirmed by small angle X-ray scattering (SAXS) and TEM. The in situ time-resolved synchrotron SAXS clearly indicates that the presence of silica colloids is critical for the formation of the highly ordered mesoporous structured phase in the precursor solution. The best results are observed on Nafion membranes with 2D-H structure in terms of proton conductivity and cell performance under reduced relative humidity (RH) conditions, achieving proton conductivities of 0.08, 0.062 and 0.038 S cm−1 at 100, 40 and 0%RH, respectively. Moreover, the power output of the mesoporous Nafion membrane cells show a S-shaped dependence on RH and are stable under anhydrous conditions (i.e., 0% RH), demonstrating the outstanding high water retention capability of the mesoporous structure of the membranes. [ABSTRACT FROM AUTHOR]

As mentioned in Part 1, for product iterative design, the digital simulation method, as the product performance analysis method, has the problems of time cost and computing resources. To address this issue, a product performance rapid simulation approach driven by digital twin (DT) data for variable product structures in Part 1 was proposed, which could replace the digital simulation method. Meanwhile, for performance analysis under variable operating conditions during the product design and operation phase, digital simulation also has the above problems. Therefore, based on the method for variable product structures proposed in Part 1, a product performance rapid simulation approach driven by DT data for variable operating conditions is proposed in this paper. Firstly, the framework for variable operating conditions is designed based on the makeTwin reference architecture, including twin source data acquisition for the product under different operating conditions, twin data-driven product performance rapid simulation model (RSM) construction for variable operating conditions, and rapid evaluation of product critical performance based on RSM. Then, the implementation of the framework is introduced in detail. At last, a case study for critical loosening load evaluation of bolted joint is carried out. The result indicates that the proposed method is feasible, as well as costs shorter simulation time than the traditional digital simulation method. [ABSTRACT FROM AUTHOR]

The vibration response generated by the operation of a metro system has a profound impact on the physical and mental well-being of urban residents. Vibration control is essential to effectively isolate the multi-band vibration response and structure-borne noise of buildings. Laminated rubber bearings between the foundation and the superstructures serve as a common, cost-effective solution for the seismic isolation of structures and have great potential to be used for metro-induced vibration mitigation. In this study, two types of full-scale laminated rubber bearings (i.e., linear natural rubber bearing and lead rubber bearing) were tested under various compressive stresses, ranging from 5 MPa to 15 MPa, to examine the static and dynamic characteristics of the bearings, including vertical hysteresis curves, vertical static stiffness, time history response, and frequency spectrum. Then, the numerical simulation of a base-isolated building structure equipped with laminated rubber bearings was conducted to evaluate the vertical vibration isolation performance and structure-borne noise isolation capability. It was demonstrated that the laminated rubber bearings have stable vertical bearing capacities and performance in isolating vertical vibrations. • Full-scale vertical static and dynamic tests of laminated rubber bearings under compressive stresses are conducted. • The laminated rubber bearings exhibit consistently stable performance in isolating vertical vibrations. • A numerical analysis confirms excellent performance in isolating both metro-induced vibrations and structure-borne noise. [ABSTRACT FROM AUTHOR]

The tensile behaviour of engineered cementitious composites (ECC) is highly dependent on their microstructure characteristics. To date, the strain-hardening behaviour of printed ECC in relation to its microstructure is not yet fully understood. This study presents a systematic investigation on the macroscopic mechanical properties of normal and printed ECC with various polyethylene (PE) fibre lengths (6 and 12 mm) in relation to their microstructural features in terms of pore structure characteristics, fibre orientation and fibre dispersion through a series of mechanical tests and X-ray computed tomography (CT) and backscattered electron (BSE) image acquisition, processing and analysis. Results indicate that it is desirable to use block specimens for mould-casting fabrication as contrast to printed ECC samples. The printed ECC containing 1.5 vol% 6 mm and 0.5 vol% 12 mm PE fibres by extrusion-based 3D printing exhibits unique tensile ductility of over 5% and average crack width of less than 100 μm. Regarding pore structure, normal ECC has a higher probability of large pores (over 1 mm3) than printed ECC, which would increase the risk of damage localization and lead to a significant variation in tensile properties. Besides, normal ECC with thickness of 30 mm and printed ECC possess a similar fist cracking strength as indicated by similar pore size and fracture toughness. Compared to normal ECC, printed ECC has a more uniform dispersion of PE fibres, the orientation of which is more perpendicular to the loading direction, resulting in a higher average tensile strength and strain capacity than normal ECC. [ABSTRACT FROM AUTHOR]

• The new digital shearography meets the requirements of high standards, making it suitable for dynamic tests while providing high-quality phase maps. • Both shearing direction and amount can be controlled quantitatively and accurately. • Phase maps can be evaluated with a single exposure. • High light efficiency and accurate phase demodulation lead to high-quality phase maps. Digital shearography (DS), a laser-based optical interferometric method, is widely employed for measuring the first-order derivative of an object's surface deformation. Unlike digital holography, DS integrates self-reference optics, enhancing resistance to environmental disturbance and improving detection sensitivity, making it ideal for non-destructive testing (NDT). DS finds applications in diverse fields such as material inspection, fluid property research, medical diagnostics, cultural heritage restoration, and military defense. The conventional temporal phase-shift (TPS) method encounters limitations in dynamic tests, leading to the introduction of the spatial phase-shift (SPS) method. However, SPS is restricted by aperture size, impacting the phase map quality. The spatial light modulator (SLM) introduces a novel approach to DS system development, enabling quantitative shearing adjustments through precise SLM control. Existing DS systems using traditional phase-shift technology rely on interferometers and struggle to achieve high-quality phase maps with a single exposure. The proposed high-performance DS, leveraging both SLM and a micro-polarizer camera, overcomes this limitation, facilitates single-exposure phase map evaluation with the polarization phase-shift technique, and eliminates the need for a tiny aperture, enhancing light beam utilization and phase map quality. [ABSTRACT FROM AUTHOR]

• The synergistic combination of microwave technology and mixed-linker strategy in COF synthesis. • This synthetic approach enables the facile and rapid synthesis of isoreticular mixed-linker COFs within an hour under air. • This approach enables fine-tuning of the physicochemical properties of COFs and thus tailors the adsorption performance towards iodine vapor. • The obtained mixed-linker COF manifested exceptional iodine adsorption capability compared to most existing COF adsorbents. The use of covalent organic frameworks (COFs) for hazardous radioiodine capture has been highly sought after recently. However, the synthesis of high-performance COF adsorbents while circumventing the limitations of traditional solvothermal methods remains largely unexplored. Herein, we for the first time combine microwave-assisted synthesis and mixed-linker strategy to fabricate multivariate COF adsorbents (X% OMe-TFB-BD COFs, X% = 0, 33, 50, 67, and 100 mol%) with varying ratios of benzidine (BD) and 3,3′-dimethoxylbenzidine (BD-OMe) linkers in a rapid and facile manner. Adjusting the BD-OMe/BD mole ratios has led to distinct variations in density, crystallinity, porosity, morphology, and thermal/chemical stability of the resultant COFs, which empowered fine-tuning of the adsorption performance towards static iodine vapor. Remarkably, the 50 % OMe-TFB-BD COF exhibited an ultrahigh iodine adsorption capability of 8.2 g g−1, surpassing those of single-component COFs, mixed-linker COFs with other methoxy content, physically blended mixtures, and most existing COF adsorbents. Moreover, 50 % OMe-TFB-BD COF was recyclable seven times without obvious loss in its adsorption capacity. This work underscores the substantial potential of microwave-assisted mixed-linker strategy as a viable approach for developing multivariate COFs with shortened reaction times, precisely tailored pore environment, and tunable sorption properties, which are of considerable promise for environmental remediation and other niche applications. Enormous efforts have been dedicated to exploring the application of covalent organic frameworks (COFs) in capturing hazardous radioiodine. However, the synthesis of efficient COF adsorbents while overcoming the limitations of traditional solvothermal methods remains largely unexplored. In this study, we present a facile microwave-assisted mixed-linker strategy to afford multivariate COF adsorbents, which exhibited tunable and ultrahigh adsorption performance towards radioiodine vapor. This novel strategy paves a facile, rapid, and engery-efficent avenue to access multivariate COFs tailored for environmental remediation. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) isolation bearings are effective means to reduce the adverse effects of metro vibrations on structures. The current research focuses on the relationship between the vertical stiffness and metro vibration isolation performance of bearings, but neglects the vibration filtering effect resulting from the inherent resonance and material damping effect of them. In this study, a novel 3D isolation bearing was proposed, composed of spring bearings (SBs) and laminated nature rubber bearings (LNR) vertically in series (denoted as 3DSL), and not only its vertical stiffness but also vibration filtering effect on metro-induced vibration isolation performance were fully studied. The design principle and vibration isolation mechanism of the 3DSL were described, followed by the design and test of three specimens. After that, a case study was conducted to investigate the influence of the 3DSL's filtering effect on metro vibration isolation. The results indicated that the 3DSL exhibited high vertical loading capacity and low vertical stiffness. Furthermore, it was found that the vibration amplitude was slightly amplified in the low-frequency range (1–50 Hz), while significantly reduced in the high-frequency range (50–200 Hz) due to the vibration filtering effect of the 3DSL. Altogether, these results demonstrated that the excellent metro vibration isolation performance of the 3DSL was attributed to the low vertical stiffness and vibration filtering effect. It is recommended to consider both the reduction of vertical stiffness and vibration filtering effect of 3D isolation bearings when designing isolation systems for metro vibrations. • A 3D isolation bearing (3DSL) was proposed for metro vibration isolation. • Mechanical properties and vibration filtering effect of 3DSL in metro vibrations were studied. • 3DSL exhibited high vertical loading capacity and low vertical stiffness. • 3DSL amplified low-frequency (1–50 Hz) but significantly reduced high-frequency (50–200 Hz) metro vibrations. • It is recommended to consider both the reduction of vertical stiffness and vibration filtering effect of 3D isolation bearings when designing isolation systems for metro vibrations. [ABSTRACT FROM AUTHOR]

Electrochemical nitrogen reduction reaction (ENRR) is a mild and environmentally friendly process that can be potentially complementary to the traditional Haber-Bosch process. Development of high-performance ENRR catalysts and understanding of the activity origin of the catalyst are essential for the practical application of ENRR process. Herein, we report the size-dependent ENRR activity of monodisperse Au nanoparticles (NPs) sized ranging from 4 nm to 10 nm. 8 nm Au NPs is found to be an excellent ENRR catalyst with an ammonia production rate and Faradic efficiency of 17.49 μg h−1 mg−1 Au and 5.79%, respectively. The high ENRR performance of 8 nm Au NP is rationalized with DFT studies, which indicate that an optimal proportion of the surface step sites is key to suppressing hydrogen evolution reaction and improving the catalytic activity towards ENRR. The study herein may provide guidelines for tailoring the ENRR catalysis on nanostructured metal catalysts. Image 1 • Monodisperse Au NP is synthesized and used for ENRR. • Au NP with a diameter of ∼8 nm shows highest ENRR activity. • The 8 nm Au has a balanced fraction of corner site and edge site. [ABSTRACT FROM AUTHOR]

The possibility of utilizing a honeycomb-like modulation pattern in a spatial light modulator (SLM) for multi-directional synchronous digital shearography measurements has been investigated. Each modulation pixel in the honeycomb-like pattern modulates the shearing amount in different directions, thus avoiding the resolution loss associated with previous methods where a single pixel could only modulate a specific shearing direction. It was demonstrated that high-quality phase maps for different shearing directions can be simultaneously obtained with a single exposure.

Abstract: Interpreting genes of interest is essential for identifying molecular mechanisms, but acquiring such information typically involves tedious manual retrieval. To streamline this process, the fanyi package offers tools to retrieve gene information from sources like National Center for Biotechnology Information (NCBI), significantly enhancing accessibility. Additionally, understanding the latest research advancements and sharing achievements are crucial for junior researchers. However, language barriers often restrict knowledge absorption and career development. To address these challenges, we developed the fanyi package, which leverages artificial intelligence (AI)-driven online translation services to accurately translate among multiple languages. This dual functionality allows researchers to quickly capture and comprehend information, promotes a multilingual environment, and fosters innovation in academic community. Meanwhile, the translation functions are versatile and applicable beyond biomedicine research to other domains as well. The fanyi package is freely available at https://github.com/YuLab-SMU/fanyi ., (Copyright © 2024 The Chinese Medical Association, produced by Wolters Kluwer, Inc. under the CC-BY-NC-ND license.)

Bolstered by their unique atomic structures and tailored compositions, nanoalloys exhibit extraordinary properties making them ideal materials to solve challenges in energy storage and conversion catalysis. However, a quantitative description of the structure-property relationships using an accurate descriptor-based model for nanoalloys, ranging from bimetallic to multimetallic compositions, is needed to drive efficient material design toward high-performance catalysis. In this work, we highlight the electronic property and catalytic activity relationship from an element specific d -band analysis of Pt-based alloy catalysts using X-ray absorption near-edge spectroscopy (XANES). Using a series of L1 0 -MPt/Pt (M = Fe, Co, Ni) core/shell alloy catalysts with well-defined atomic structures, we quantified subtle differences in the Pt d -electron states and correlated the Pt d -band structure to their superior catalytic activity toward the oxygen reduction reaction (ORR). Our analysis used the upper d -band edge position as a predictive descriptor for the mass activity toward the ORR instead of the commonly used d -band center position. Together with density functional theory calculations and Nørskov d -band theory, the upper d -band edge position for the Pt states, derived from experimental measurements, elucidates new physical insights into the ORR performance of the L1 0 -MPt/Pt core/shell catalysts. An element specific Pt d -band analysis using XANES overcomes challenges in traditional X-ray photoelectron spectroscopy-based valence d -band analysis, which cannot distinguish signals from independent elements in nanoalloys. Thus, the insights from the element specific d -band analysis presented in this work are a promising approach to determine structure-property relationships in a variety of transition metal nanoalloys and will be useful in the design of future high-performance catalysts.

Platelet-activating factor (PAF) is a potent phospholipid mediator crucial in multiple inflammatory and immune responses through binding and activating the PAF receptor (PAFR). However, drug development targeting the PAFR has been limited, partly due to an incomplete understanding of its activation mechanism. Here, we present a 2.9-Å structure of the PAF-bound PAFR-G i complex. Structural and mutagenesis analyses unveil a specific binding mode of PAF, with the choline head forming cation-π interactions within PAFR hydrophobic pocket, while the alkyl tail penetrates deeply into an aromatic cleft between TM4 and TM5. Binding of PAF modulates conformational changes in key motifs of PAFR, triggering the outward movement of TM6, TM7, and helix 8 for G protein coupling. Molecular dynamics simulation suggests a membrane-side pathway for PAF entry into PAFR via the TM4-TM5 cavity. By providing molecular insights into PAFR signaling, this work contributes a foundation for developing therapeutic interventions targeting PAF signal axis., Competing Interests: Declaration of interests H.E.X. is a founder of Cascade Pharmaceutics., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Introduction: Flow, defined as a heightened state of consciousness characterized by intense concentration during an activity, is influenced primarily by the perceived challenge and the dynamic equilibrium of skills. This investigation focuses on the patterns of flow state attainment and its elicitation mechanisms within the context of piano performance among Chinese music college students., Methods: Our study establishes a framework for accessing flow, utilizing quantitative data from music ontology to gauge the level of challenge and the level of music acquisition to assess skills. Additionally, we integrate external factors such as music culture heterogeneity and demographic variables to elucidate the causes and moderating effects of flow on piano performance., Results: The findings reveal a positive correlation between flow and performance, with the model of challenge and skill induction partially explaining these results. Notably, melodic Shannon Entropy emerges as a potential indicator of challenge, suggesting its relevance in future studies on flow., Discussion: This research provides multidimensional insights into the interplay between performance and flow in piano performance, guiding future investigations to explore the musical quantitative perspective more deeply., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Xu, Wang, Yuan, Liu, Li, Ren, Yang, Liu, Jiang, Gou, Yang and Xu.)

The gait rehabilitation knee exoskeleton is an advanced rehabilitative assistive device designed to help patients with knee joint dysfunction regain normal gait through training and activity support. This paper introduces a design framework based on the process knowledge representation method to optimize the design and control efficiency of the knee exoskeleton. This framework integrates knowledge of design objects and processes, specifically including requirements, functions, principle work areas, and the representation and multi-dimensional dynamic mapping of the Behavior-Structure (RFPBS) matrix, achieving multi-dimensional dynamic mapping of the knee exoskeleton. This method incorporates biomechanical and physiological knowledge from the rehabilitation process to more effectively simulate and support gait movements during rehabilitation. Research results indicate that the knee rehabilitation exoskeleton design, based on the RFPBS process knowledge representation model, accomplishes multi-dimensional dynamic mapping, providing a scientific basis and effective support for the rehabilitation of patients with knee joint dysfunction.