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Recent progress in electrochemical hydrogen sulfide splitting: Strategies for enabling Sulfur-tolerant anodic reactions
No full textWater splitting is widely recognized as the cleanest method for producing green hydrogen. Unfortunately, its efficiency is severely impeded by the sluggish oxygen evolution reaction (OER) occurring on the anode. In contrast, the electrochemical sulfide oxidation reaction (SOR) offers greater thermodynamic and kinetic ad-vantages. Combining the SOR with the hydrogen evolution reaction (HER) can permit hydrogen sulfide (H2S) splitting to simultaneously generate green hydrogen by lowering the energy input, mitigating environmental pollution, and recovering valuable sulfur compounds. This review provides a synopsis of recent developments in electrochemical H2S splitting, with a focus on the anodic electron transfer from sulfide to the anode via direct electrocatalysis or an indirect redox-mediated pathway. Attention has been paid to strategies that can mitigate the critical issue of poisoning caused by insoluble sulfur species formed during the SOR. Furthermore, recent advances in the development of active, robust, and sulfur-tolerant electrocatalysts and redox mediators that permit a stable SOR with resistance against sulfur-driven deterioration are explored. Finally, the current chal-lenges and future research directions of this highly promising but underexplored field are examined to encourage further research in this area
A skin-friendly soft strain sensor with direct skin adhesion enabled by using a non-toxic surfactant
No full textWearable electronics, particularly soft strain sensors with direct skin adhesion, play a crucial role in applications such as smart healthcare systems and human-machine interfaces. However, the existing approaches for developing dry-adhesive soft electronic materials often involve potential biotoxicity and vulnerability to humid environments. In this study, we present an eco-friendly and biocompatible surfactant-based composite for soft conductive composite, soft dry-adhesive film, and skin-adherable soft strain sensors. Utilizing polyoxyethylene sorbitan monooleate, also known as Tween 80, as a non-toxic surfactant, polydimethylsiloxane (PDMS) as an elastomeric matrix, and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) as a conductive pathway, the composite exhibits excellent stretchability and conductivity. The soft dry-adhesive film based on Tween 80-added PDMS features exceptional softness and adhesiveness. We demonstrate a soft strain sensor based on these composites that can be directly adhered to the skin and effectively detect various human motions involving large deformations without delamination. This approach offers a promising avenue for future wearable electronics that are safe for both humans and the environment
Exploring the degradation pathways of a nickel-rich cathode during high-temperature storage in high-energy lithium-ion batteries
No full textThe degradation of nickel-based cathodes under high temperature is challenging for expanding their application to electric vehicles (EVs) and stationary energy storages. While a majority of the research focuses on the improving performances and degradation mechanisms for long-term cycling, relatively less studies are published regarding the long-term storage conditions. Herein, we discuss a high-temperature calendar life of Ni-rich cathode using systematic protocols with high-energy lithium-ion cell. Although the final capacity retention after the calendar life test is the same with & SIM;70% compared to the original cell capacity, Ni-rich cathode showed diverse degradation behavior depending on the calendar temperature of 45 & DEG;C and 60 & DEG;C. The major degradation factor for cells stored at 60 & DEG;C is the loss of lithium inventory; however, there was a severe loss of the active material in the cells stored at 45 & DEG;C as well as lithium inventory loss
Overview of fusion-like neutron sources based on high-intensity linear accelerators
No full textA dedicated linear accelerator for continuous wave (CW) D+ beams to generate fusion-like neutrons is crucial for the breeding blanket module tests and fusion material irradiation experiments. In this article, we introduce the world-wide activities for such accelerator facilities. Then, we present the case study, pre-conceptual design, and major component specification overview for developing a linear accelerator that could provide the modest beam parameters (40 MeV, maximum 10 mA CW) for breeding module tests. We look into the specifications of the facility and prepare a layout of the envisioned accelerator, which could be aligned with the Korean domestic fusion program. We also carry out the preliminary beam dynamics/optics calculations and operation scenario development
Towards Customer Outcome Management in Smart Manufacturing
No full textThe outcome economy is a relatively new economic and business paradigm that promotes focusing on the effects that the use of provided products and services create for customers in their markets, rather than focusing on these products or services themselves from the providers' perspective. This paradigm has been embraced in various fields of business but has not yet been fully integrated with the concept of smart industry. To fill this gap, in this vision paper we provide a framework that does make this integration, showing the full structure of customer outcome management in smart manufacturing, from both business and digital technology perspectives. In applying this structure, a feedback loop is created that spans the markets of provider and customer and supports data-driven product evolution, manufacturing, and delivery. We propose a business reference framework that can be used as a blueprint for designing practical scenarios. We show how integrated digital support for such a scenario can be realized using a well-structured combination of technologies from the fields of the internet of things, business intelligence and federated learning, blockchain, and business process management. We illustrate all of this with a visionary case study inspired by industrial practice in the automotive domain. In doing so, we provide both an academic basis for the integration of several currently dispersed research fields that need to be integrated to further smart manufacturing towards outcome management and a practical basis for the well-structured design and implementation of customer outcome management business cases in smart manufacturing
HOW-MHD: A High-order WENO-based Magnetohydrodynamic Code with a High-order Constrained Transport Algorithm for Astrophysical Applications
No full textDue to the prevalence of magnetic fields in astrophysical environments, magnetohydrodynamic (MHD) simulation has become a basic tool for studying astrophysical fluid dynamics. To further advance the precision of MHD simulations, we have developed a new simulation code that solves ideal adiabatic or isothermal MHD equations with high-order accuracy. The code is based on the finite-difference weighted essentially nonoscillatory (WENO) scheme and the strong stability-preserving Runge-Kutta (SSPRK) method. Most of all, the code implements a newly developed, high-order constrained transport (CT) algorithm for the divergence-free constraint of magnetic fields, completing its high-order competence. In this paper, we present the version in Cartesian coordinates, which includes a fifth-order WENO and a fourth-order five-stage SSPRK, along with extensive tests. With the new CT algorithm, fifth-order accuracy is achieved in convergence tests involving the damping of MHD waves in 3D space. And substantially improved results are obtained in magnetic loop advection and magnetic reconnection tests, indicating a reduction in numerical diffusivity. In addition, the reliability and robustness of the code, along with its high accuracy, are demonstrated through several tests involving shocks and complex flows. Furthermore, tests of turbulent flows reveal the advantages of high-order accuracy and show that the adiabatic and isothermal codes have similar accuracy. With its high-order accuracy, our new code would provide a valuable tool for studying a wide range of astrophysical phenomena that involve MHD processes
Construction of Chimeric Metal-Organic Frameworks with Symmetry-Mismatched Building Blocks
No full textChimeric metal-organic frameworks (CMOFs) composedof symmetry-mismatchedinorganic and organic building blocks are rare because the interconnectionsbetween these blocks are topologically demanding. Herein, an MOF withsymmetry-matched building blocks is used as a self-template for thetemplate-assisted synthesis of CMOFs. Specifically, the post-synthetictransformation of the [Zn4O(COO)(6)] clustersin the self-templating MOF into the [Fe-3 O-III(COO)(6)](+) clusters with symmetry-mismatched trigonal prismaticsite symmetry affords isoreticular CMOFs while maintaining the templatemorphology and crystallinity. The framework strain of CMOFs due tothe symmetry-mismatched linkages between their building blocks isreduced by modulating the conformation of organic building blockswith torsional degrees of freedom. The further transformation of [Fe-3 O-III(COO)(6)](+)-based CMOFsthrough redox-facilitated metal exchange using Cr2+ ionsyields highly stable isostructural CMOFs containing [Cr-3 O-III(COO)(6)](+) clusters and exhibitingstabilities in strongly acidic and moderately basic media comparableto those of prototypical [Cr-3 O-III(COO)(6)](+)-based MOFs with symmetry-matched building blocks. Theseresults hold significant potential and highlight the vast opportunitiesfor revisiting well-known yet fragile MOFs built upon the zinc acetateclusters
Introducing SPARTAN Instrument System for PM Analysis
No full textAs the need for PM type observation increases, Surface Particulate Matter Network (SPARTAN), PM samplers analyzes aerosol samples for PM mass concentration and chemical composition, were recently installed at two sites: Yonsei University at Seoul and Ulsan Institute of Science and Technology (UNIST) at Ulsan. These SPARTAN filter samplers and nephelometers provide the PM2.5 mass concentration and chemical speciation data with aerosol type information.
We introduced the overall information and installation of SPARTAN at the field site in this study. After installation and observation, both Seoul and Ulsan sites showed a similar time series pattern with the daily PM2.5 mass concentration of SPARTAN and the data of Airkorea. In particular, in the case of high concentrations of fine particles, daily average value of PM2.5 was relatively well-matched. During the Yonsei University observation period, high concentrations were displayed in the order of sulfate, black carbon (BC), ammonium, and calcium ions on most measurement days. The case in which the concentration of nitrate ions showed significant value was confirmed as the period during which the fine dust alert was issued. From the data analysis, SPARTAN data can be analyzed in conjunction with the existing urban monitoring network, and it is expected to have a synergetic effect in the research field. Additionally, the possibility of being analyzed with optical data such as AERONET is presented. In addition, the method of installing and operating SPARTAN has been described in detail, which is expected to help set the stage for the observation system in the future