bluuebunny/crossref_metadata_2025 huggingface dataset:
Surface‐Engineered Liquid Metal Particles for Printing Stretchable Conductive Composites with Enhanced Stability Under Different Strain Rates
Authors: Chin Ren‐Mian , Han Youngshang , Malakooti Mohammad H.
Published: September 2023

Integrating liquid metal (LM) particles into compliant polymers presents an innovative approach for developing intelligent and adaptable systems in stretchable electronics, wearable devices, soft robotics, and other emerging technologies. However, the inherent electrically insulative nature of these solid‐liquid composites, compounded by the gallium oxide shell surrounding LM droplets, poses a significant challenge in establishing conductive pathways, especially for small droplet sizes and ultrasoft elastomers. Here, an interface modification approach that addresses this bottleneck and enables the synthesis of highly stretchable and printable composites with LM microparticles (<2 µm) is presented. Polyvinylpyrrolidone (PVP) is used to functionalize these small LM inclusions, weakening the particle‐matrix interface, and facilitating the formation of a conductive percolating network under tensile strain. Optimized synthesis parameters result in printed conductive traces with excellent electrical conductivity (0.2 Ω cm−1), ultra‐high elongation at break (>900% strain), and minimal resistance change (≈131%). Furthermore, this comprehensive study of the electromechanical response of these stretchable conductors under various strain rates reveals their exceptional stability under dynamic loading conditions, surpassing the performance of conductive traces composed of sprayed liquid metal. Finally, the potential application of these multifunctional materials in stretchable circuitry, addressing the demand for high stretchability and stability in wearable electronics, is demonstrated.
Reversible Luminochromism of an N‐Heterocyclic Carbene‐Protected Carbon‐Centered Hexagold(I) Cluster by Solvent and Mechanical Stimuli
Authors: Foianesi‐Takeshige Leonardo Hayato , Pei Xiao‐Li , Zhao Pei , Ube Hitoshi , Lei Zhen , Ehara Masahiro , Shionoya Mitsuhiko
Published: September 2023

Luminochromic gold clusters have potential applications in sensing due to the unique optical properties arising from their geometric and electronic structures. However, the rational design of such clusters is extremely challenging, especially when the goal is to impart reversible stimuli‐responsive properties to gold clusters. Herein, the reversible multi‐stimuli responsiveness of a carbon‐centered hexagold(I) CAuI6 cluster protected by N,N’‐dibenzylbenzimidazolylidene (BIBn) ligands is reported. Two types of crystals emitting blue (λemmax = 479 nm) and turquoise (λemmax = 497 nm) photoluminescence (PL) are obtained and found to be interconvertible by the addition and removal of solvent. Single‐crystal X‐ray structure analysis has revealed significant differences between the crystal structures, including the conformation of the BIBn ligands. Theoretical calculations suggest that these conformational differences directly affect the photophysical properties and that the flexibility of the BIBn ligands attached to the CAuI6 core makes this possible. Furthermore, when these crystals are grounded with a spatula, they are found to emit green PL (λemmax = 520 nm) following a partial loss of crystallinity. This is a remarkable example of both vapoluminochromism and mechanoluminochromism in an N‐heterocyclic carbene (NHC)‐protected gold cluster and holds promise as a model compound for understanding the principles governing stimuli‐responsiveness in metal clusters.
Genetically Engineered Membrane‐Coated Nanoparticles as Versatile Platforms with Reduced Protein Corona for Targeted siRNA Delivery
Authors: Zhang Pengfei , Zhao Lei , Liu Heng , Chen Hu , Wu Yaming , Wang Xiaoyong , Liu Gang , Zeng Yun
Published: September 2023

Low uptake efficiency in vivo as well as systemic toxicities of nucleic‐acid nanovehicles substantially retard the clinical translation of gene therapy. Targeted gene delivery to specific cell populations with antibody display techniques and membrane‐coated nanoparticle (NP) approaches may solve these problems. Here, a new class of targeted membrane‐camouflaged nanosystem is successfully constructed, which is made of polydopamine (PDA) nanoparticles coated with biosynthetic antibody‐displaying membranes from stem cells. In murine models of rheumatoid arthritis and colitis, the membrane‐camouflaged nanocarriers displayed anti‐CD64 antibodies in a ligand‐oriented way via the biosynthetic method and has reduced protein corona due to the coating of the negatively charged cell membrane, thereby achieving remarkable therapeutic efficacy through silencing the TNF expression selectively in CD64‐positive immune cell subsets. By expressing a wide variety of functional protein ligands on the cellular membranes that are further coated onto PDA nanoparticles, the membrane‐camouflaged nanosystems can also serve as a versatile theranostic platform that enables antibody‐targeted gene/siRNA delivery to the cells of interest in vivo, especially immune cells.
“Smart” Matrix Microneedle Patch Made of Self‐Crosslinkable and Multifunctional Polymers for Delivering Insulin On‐Demand
Authors: Liu Jackie Fule , GhavamiNejad Amin , Lu Brian , Mirzaie Sako , Samarikhalaj Melisa , Giacca Adria , Wu Xiao Yu
Published: September 2023

A transdermal patch that delivers insulin at high glucose concentrations can offer tremendous advantages to ease the concern of safety and improve the quality of life for people with diabetes. Herein, a novel self‐crosslinkable and glucose‐responsive polymer‐based microneedle patch (MN) is designed to deliver insulin at hyperglycemia. The microneedle patch is made of hyaluronic acid polymers functionalized with dopamine and 4‐amino‐3‐fluorophenylboronic acid (AFBA) that can be quickly crosslinked upon mixing of the polymer solutions in the absence of any chemicalcrosslinking agents or organic solvents. The catechol groups in the dopamine (DA) units form covalent crosslinkages among themselves by auto‐oxidation and dynamic crosslink with phenylboronic acid (PBA) via complexation. The reversible crosslinkages between catechol and boronate decrease with increasing glucose concentration leading to higher swelling and faster insulin release at hyperglycemia as compared to euglycemia. Such superior glucose‐responsive properties are demonstrated by in vitro analyses and in vivo efficacy studies. The hydrogel polymers also preserve native structure and bioactivity of insulin, attributable to the interaction of hyaluronic acid (HA) with insulin molecules, as revealed by experiments and molecular dynamics simulations. The simplicity in the design and fabrication process, and glucose‐responsiveness in insulin delivery impart the matrix microneedle (mMN) patch great potential for clinical translation.
Kinetic network models to elucidate aggregation dynamics of aggregation‐induced emission systems
Authors: Liu Zige , Kalin Michael L. , Liu Bojun , Cao Siqin , Huang Xuhui
Published: September 2023

Aggregation‐induced emission (AIE) is a phenomenon where a molecule that is weakly or non‐luminescent in a diluted solution becomes highly emissive when aggregated. AIE luminogens (AIEgens) hold promise in diverse applications like bioimaging, chemical sensing, and optoelectronics. Investigation in AIE luminescence is also critical for understanding aggregation kinetics as the aggregation process is an essential component of AIE emission. Experimental investigation of AIEgen aggregation is challenging due to the fast timescale of the aggregation and the amorphous aggregate structures. Computer simulations such as molecular dynamics (MD) simulation provide a valuable approach to complement experiments with atomic‐level knowledge to study the fast dynamics of aggregation processes. However, individual simulations still struggle to systematically elucidate heterogeneous kinetics of the formation of amorphous AIEgen aggregates. Kinetic network models (KNMs), constructed from an ensemble of MD simulations, hold great potential in addressing this challenge. In these models, dynamic processes are modeled as a series of Markovian transitions occurring among metastable conformational states at discrete time intervals. In this perspective article, we first review previous studies to characterize the AIEgen aggregation kinetics and their limitations. We then introduce KNMs as a promising approach to elucidate the complex kinetics of aggregations to address these limitations. More importantly, we discuss our perspective on linking the output of KNMs to experimental observations of time‐resolved AIE luminescence. We expect that this approach can validate the computational predictions and provide great insights into the aggregation kinetics for AIEgen aggregates. These insights will facilitate the rational design of improved AIEgens in their applications in biology and materials sciences.
Plasma Photocathodes
Authors: Habib Ahmad Fahim , Heinemann Thomas , Manahan Grace G. , Ullmann Daniel , Scherkl Paul , Knetsch Alexander , Sutherland Andrew , Beaton Andrew , Campbell David , Rutherford Lorne , Boulton Lewis , Nutter Alastair , Hewitt Adam , Dickson Alexander , Karger Oliver S. , Litos Michael D. , O'Shea Brendon D. , Andonian Gerard , Bruhwiler David L. , Pretzler Georg , Wilson Thomas , Sheng Zhengming , Stumpf Michael , Reichwein Lars , Pukhov Alexander , Cary John R. , Hogan Mark J. , Yakimenko Vitaly , Rosenzweig James B. , Hidding Bernhard
Published: September 2023

Plasma wakefield accelerators offer accelerating and focusing electric fields three to four orders of magnitude larger than state‐of‐the‐art radiofrequency cavity‐based accelerators. Plasma photocathodes can release ultracold electron populations within such plasma waves and thus open a path toward tunable production of well‐defined, compact electron beams with normalized emittance and brightness many orders of magnitude better than state‐of‐the‐art. Such beams will have far‐reaching impact for applications such as light sources, but also open up new vistas on high energy and high field physics. This paper reviews the innovation of plasma photocathodes, and reports on the experimental progress, challenges, and future prospects of the approach. Details of the proof‐of‐concept demonstration of a plasma photocathode in 90° geometry at SLAC FACET within the E‐210: Trojan Horse program are described. Using this experience, alongside theoretical and simulation‐supported advances, an outlook is given on future realizations of plasma photocathodes such as the upcoming E‐310: Trojan Horse‐II program at FACET‐II with prospects toward excellent witness beam parameter quality, tunability, and stability. Future installations of plasma photocathodes also at compact, hybrid plasma wakefield accelerators, will then boost capacities and open up novel capabilities for experiments at the forefront of interaction of high brightness electron and photon beams.
Two‐component polymer sorting to obtain high‐purity s‐SWCNTs for all‐carbon photodetectors
Authors: Zheng Dandan , Yi Wenhui , Zhou JinFeng , Hou Jin , Si Jinhai , Hou Xun
Published: September 2023

The advancement of carbon‐based electronics is reliant on the development of semiconducting carbon nanotubes with high purity and yield. We developed a new extraction strategy to efficiently sort SWCNTs with superior yields and purity. The approach uses two polymers, poly[N‐(1‐octylnonyl)‐9H‐carbazol‐2,7‐diyl](PCz) and poly(9,9‐n‐dihexyl‐2,7‐fluorene‐alt‐9‐phenyl‐3,6‐carbazole)(PDFP), and two sonication processes to eliminate surface polymer contamination. PCz selectively wraps large‐diameter s‐SWCNTs, with PDFP added as an enhancing molecule to increase sorting efficiency at 4‐fold compared to the efficiency of only PCz alone sorting. The purity of the sorted s‐SWCNTs was confirmed to be above 99 % using absorption and Raman spectra. Field‐effect transistors and photodetectors made from the sorted s‐SWCNTs exhibited excellent semiconductor properties and broad‐spectrum detection, with good long‐term stability. Furthermore, a photodetector using large‐tube diameter s‐SWCNTs achieved broad‐spectrum detection, which the photoresponsivity is 0.35 mA/W and the detectivity is 4.7×106 Jones. The s‐SWCNTs/graphene heterojunction photodetector achieved a photoresponsivity of 3 mA/W and a detectivity of 6.3×106 Jones. This new strategy provides a promising approach to obtain high‐purity and high‐yield s‐SWCNTs for carbon‐based photodetectors.
A new bounded real lemma for discrete‐time linear descriptor systems
Authors: Wu Jenq‐Lang , Yung Chee‐Fai , Liu Wei‐Ting
Published: September 2023

This paper presents a new bounded real lemma for discrete‐time linear descriptor systems. We first present a necessary and sufficient condition for the admissibility of discrete‐time descriptor systems expressed in terms of strict linear matrix inequalities (LMIs). We then prove that a discrete‐time descriptor system is
‐stable if and only if a symmetric matrix satisfying two strict LMIs can be found. Two illustrative examples are provided for verification.
Morphology‐Dependent Influences on the Performance of Battery Cells with a Hierarchically Structured Positive Electrode**
Authors: Naumann Johanna , Bohn Nicole , Birkholz Oleg , Neumann Matthias , Müller Marcus , Binder Joachim R. , Kamlah Marc
Published: September 2023

The rising demand for high‐performing batteries requires new technological concepts. To facilitate fast charge and discharge, hierarchically structured electrodes offer short diffusion paths in the active material. However, there are still gaps in understanding the influences on the cell performance of such electrodes. Here, we employed a cell model to demonstrate that the morphology of the hierarchically structured electrode determines which electrochemical processes dictate the cell performance. The potentially limiting processes include electronic conductivity within the porous secondary particles, solid diffusion within the primary particles, and ionic transport in the electrolyte surrounding the secondary particles. Mitigating these limits requires an electronic conductivity in the active material of at least 10−4 S m−1 and a primary particle radius below 100 nm. Our insights enable a goal‐oriented tailoring of hierarchically structured electrodes for high‐power applications.
Oxygen Vacancy Modulation towards High‐Performance Layered Oxide Cathodes for Lithium/Sodium‐Ion Batteries
Authors: Jin Junteng , Liu Yongchang , Chen Jun
Published: September 2023

Oxygen vacancies (Vo) as a common structural defect play a critical and fascinating role in regulating the physico‐chemical properties of metal oxides. For the layered transitional‐metal oxides (LTMOs) used as the popular cathodes for lithium/sodium‐ion batteries (LIBs or SIBs), Vo can modulate their intrinsic multi‐scale structural properties, thereby significantly affecting the final electrochemical performance. In this concept article, we summarize the fundamental structural regulation mechanisms of Vo in lithium/sodium‐based LTMOs in terms of ligand, local, and crystal structures. Finally, the current challenges and outlooks of Vo engineering are highlighted for future development of high‐performance layered oxide cathode materials.
Blood biomarker changes following therapeutic hypothermia in ischemic stroke
Authors: Palà Elena , Penalba Anna , Bustamante Alejandro , García‐Berrocoso Teresa , Lamana‐Vallverdú Marcel , Meisel Christian , Meisel Andreas , van der Worp H. Bart , R Macleod Malcolm , Kallmünzer Bernd , Schwab Stefan , Montaner Joan
Published: September 2023

Introduction

Therapeutic hypothermia is a promising candidate for stroke treatment although its efficacy has not yet been demonstrated in patients. Changes in blood molecules could act as surrogate markers to evaluate the efficacy and safety of therapeutic cooling.

Methods

Blood samples from 54 patients included in the EuroHYP‐1 study (27 treated with hypothermia, and 27 controls) were obtained at baseline, 24 ± 2 h, and 72 ± 4 h. The levels of a panel of 27 biomarkers, including matrix metalloproteinases and cardiac and inflammatory markers, were measured.

Results

Metalloproteinase‐3 (MMP‐3), fatty‐acid‐binding protein (FABP), and interleukin‐8 (IL‐8) increased over time in relation to the hypothermia treatment. Statistically significant correlations between the minimum temperature achieved by each patient in the hypothermia group and the MMP‐3 level measured at 72 h, FABP level measured at 24 h, and IL‐8 levels measured at 24 and 72 h were found. No differential biomarker levels were observed in patients with poor or favorable outcomes according to modified Rankin Scale scores.

Conclusion

Although the exact roles of MMP3, FABP, and IL‐8 in hypothermia‐treated stroke patients are not known, further exploration is needed to confirm their roles in brain ischemia.
Analysis of child abuse by science mapping method
Authors: Unaldi Nurdan
Published: September 2023

Child abuse is defined as physical and emotional maltreatment, sexual abuse, neglect and exploitation that cause actual or potential harm to the child's health, development, or dignity. Bibliometrics analyses works produced in a particular field, period and region. It is used to determine the studies carried out in any field, their development and changes in the process, and possible trends. The Web of Science Core Collection database was preferred due to the vast amount of high‐quality and effective scientific articles accepted in academic environments worldwide. The data obtained from the database were extracted and filtered. The Bibliometrix program was used to perform a bibliometric analysis of the data obtained from the database. In our research, 2684 articles were analysed. The first scientific study on child abuse research was entered into the database in 1980. It was used in 786 sources and 2684 documents between 1980 and 2021. Child Abuse & Neglect is the journal with the most publications, representing 15.05 per cent (404/2684) of the total articles. The publication of articles on child abuse in journals started in the 1980s. An increase was observed in the number of articles published in the following years.
Solvent‐Free Selective Oxidation of Benzyl Alcohol at Atmospheric Pressure Catalyzed by Pd Nanoparticles Supported on g‐C3N4 Materials with Tunable Nitrogen Distributions
Authors: Li Chun‐Yuan , Feng Meng , Cui Lei , Wang Fei , Xue Bing , Xu Jie
Published: September 2023

Solvent‐free atmospheric selective oxidation of benzyl alcohol (BZA) by molecular oxygen is a promising and green process for the synthesis of benzaldehyde (BZL). Supported Pd nanoparticles have been widely reported in the catalytic selective oxidation of BZA where the activity depends on the chemical valence and dispersion of the Pd nanoparticles. Herein, a series of thermally exfoliated g‐C3N4 (eg‐C3N4) have been synthesized under various gas conditions (air/N2) and then applied as catalyst supports to load Pd nanoparticles. The physicochemical properties of the prepared Pd/eg‐C3N4 materials have been characterized by N2 adsorption–desorption, XRD, FT‐IR, UV‐vis, XPS, and TEM. Pd nanoparticles dispersed well on the supports, and the distributions of Pd and nitrogen species of the catalysts were related to the gas conditions of the supports. In the selective oxidation of BZA, 2.5Pd/eg‐C3N4‐AN catalyst afforded conversion of BZA and the selectivity to BZL of 88 % and 92 %, respectively. The metallic Pd0 species are considered the catalytic sites of Pd/eg‐C3N4 in the catalytic reaction and meanwhile, the basic Nb species of eg‐C3N4 were beneficial to the overall activity of the catalyst.
Elucidating the Role of Oxygen Species in Oxidative Coupling of Methane over Supported MnOx−Na2WO4‐containing Catalysts
Authors: Zanina Anna , Kondratenko Vita A. , Makhmutov Denis , Lund Henrik , Li Jianshu , Chen Juan , Li Yuming , Jiang Guiyuan , Kondratenko Evgenii V.
Published: September 2023

The present study of oxidative coupling of methane (OCM) over MnOx−Na2WO4/support catalysts demonstrated that the selectivity to C2H6 and C2H4 (C2‐hydrocarbons) is affected by the kind of support, co‐fed water, and the kind of oxidant (O2 vs. N2O). In addition to previous studies with MnOx−Na2WO4/SiO2, an enhancing water effect was obtained using catalysts based on TiO2‐ or ZrO2‐containing supports. However, a negative effect on methane conversion was established for SiO2−Al2O3‐supported catalysts. Temporal analysis of products with isotopic tracers suggests that the ability of MnOx−Na2WO4 to generate diatomic adsorbed oxygen species depends on the kind of support and is the key property for the water effect. The strength of the water effect on the activity decreases with an increase in the surface area of working catalysts. The kind of support also affects products selectivity due to its influence on the mobility/releasability of lattice oxygen in supported MnOx−Na2WO4. Among the prepared catalysts, MnOx−Na2WO4/TiO2 was found to be promising for H2O‐assisted OCM. The use of N2O instead of O2 further increases the selectivity to C2‐hydrocarbons to 84 % at 6.8 % CH4 conversion due to the formation of predominantly monoatomic oxygen species from N2O that selectively convert CH4 into C2H6.
Adaptive Data‐Driven Modeling Strategy Based on Feature Selection for an Industrial Natural Gas Sweetening Process
Authors: Jiang Wei , Li Jinjin , Chen Guanshan , Luo Renjiang , Chen Yan , Ji Xu , Li Zhuoxiang , He Ge
Published: September 2023

As the core process of natural gas purification plant, natural gas sweetening directly affects the production efficiency and product quality of the purification plant. However, process modeling based on sulfur content prediction presents challenges in adaptability and accuracy. To tackle this, a machine learning‐based modeling approach is proposed that integrates an adaptive immune genetic algorithm with random forest (RF) to intelligently select process features as input variables for RF modeling. The industrial result indicates that the proposed method is able to remove interfering variables and adaptively achieve optimal model precision for different scenarios. It offers a novel research instrument for product quality monitoring in natural gas sweetening plants.
Lattice Tuning of Copper Single‐Crystal Surface for Electrochemical Carbon Monoxide Coupling Reaction: A Density Functional Theory Simulation
Authors: Zhang Xia‐Guang , Chen Si , Zheng Tao , Xuan Xiaopeng , Wen Yaping
Published: September 2023

CO is a key intermediate of electrocatalytic CO2 reduction reaction, which determines the product species. Understanding the effect of metal electrode structure on the adsorption ability and reaction activity of CO is helpful for the design of high selective catalysts. Herein, the DFT calculations are used to investigate the relationship between lattice structure and reaction mechanism of CO, with copper electrode of various lattice constants used as catalysts. By analyzing the adsorption and reaction energies of CO at different lattice constants of Cu(111) and Cu(100) surfaces, we found that the CO adsorption ability is proportional to the increase in lattice, and *CO dimerization to *COCO is the main reaction pathway on Cu(100) surface. Furthermore, the forecasted possible reaction mechanism and products suggest that the coupling of *CO and *CHO to *COCHO and then to C2 products is the preferred pathway on Cu(111) surface for the lattice contraction. Alternatively, reduction of *CO to C1 products through *CHO intermediate is more beneficial for the normal and expanded lattice of Cu(111). This work offers an example of the geometrical influence factor on the CO adsorption ability and reaction activity, and helps to understanding the fundamental role of lattice expansion and contraction in catalysis.
Photovoltaic Wafering Silicon Kerf Loss as Raw Material: Example of Negative Electrode for Lithium‐Ion Battery**
Authors: Heintz Mads C. , Grins Jekabs , Jaworski Aleksander , Svensson Gunnar , Thersleff Thomas , Brant William R. , Lindblad Rebecka , Naylor Andrew J. , Edström Kristina , Hernández Guiomar
Published: September 2023

Silicon powder kerf loss from diamond wire sawing in the photovoltaic wafering industry is a highly appealing source material for use in lithium‐ion battery negative electrodes. Here, it is demonstrated for the first time that the kerf particles from three independent sources contain ~50 % amorphous silicon. The crystalline phase is in the shape of nano‐scale crystalline inclusions in an amorphous matrix. From literature on wafering technology looking at wafer quality, the origin and mechanisms responsible for the amorphous content in the kerf loss powder are explained. In order to better understand for which applications the material could be a valuable raw material, the amorphicity and other relevant features are thoroughly investigated by a large amount of experimental methods. Furthermore, the kerf powder was crystallized and compared to the partly amorphous sample by operando X‐ray powder diffraction experiments during battery cycling, demonstrating that the powders are relevant for further investigation and development for battery applications.
Boosting the Cell Performance of the SiO/Cu and SiO/PPy Anodes via In‐Situ Reduction/Oxidation Coating Strategies
Authors: Luo Tan , Che Yanyun , Lu Xingjie , Wang Guifang , Cai Jinming , Lu Jianchen , Yi Jianhong , Fang Dong
Published: September 2023

Silicon monoxide (SiO) has attracted great attention due to its high theoretical specific capacity as an alternative material for conventional graphite anode, but its poor electrical conductivity and irreversible side reactions at the SiO/electrolyte interface seriously reduce its cycling stability. Here, to overcome the drawbacks, the dicharged SiO anode coated with Cu coating layer is elaborately designed by in‐situ reduction method. Compared with the pristine SiO anode of lithium‐ion battery (293 mAh g−1 at 0.5 A g−1 after 200 cycles), the obtained SiO/Cu composite presents superior cycling stability (1206 mAh g−1 at 0.5 A g−1 after 200 cycles). The tight combination of Cu particles and SiO significantly improves the conductivity of the composite, effectively inhibits the side‐reaction between the active material and electrolyte. In addition, polypyrrole‐coated SiO composites are further prepared by in‐situ oxidation method, which delivers a high reversible specific capacity of 1311 mAh g−1 at 0.5 A g−1 after 200 cycles. The in‐situ coating strategies in this work provide a new pathway for the development and practical application of high‐performance silicon‐based anode.
Two‐Dimensional Covalent Organic Frameworks as Tailor‐Made Scaffolds for Water Harvesting
Authors: Wen Fuxiang , Wu Xinyu , Li Xiangyu , Huang Ning
Published: September 2023

Developing materials to harvest water from the air is of great importance to alleviate the water shortage for people living in arid regions, where the annual average relative humidity (RH) is lower than 0.4. In this work, we report a general nitrogen atom incorporation strategy to prepare high‐performance covalent organic frameworks (COFs) for water harvesting from the air in arid areas. A series of COFs, namely COF‐W1, COF‐W2, and COF‐W3 were developed for this purpose. Different contents of nitrogen were embedded into COFs by incorporating pyridine units into the building blocks. With the increasing content of nitrogen from COF‐W1 to COF‐W3, the inflection points of their water isotherms shift distinctly from RH values from 0.65 to 0.25. Significantly, COF‐W3 exhibits the lowest inflection point at a low RH value of 0.25 and reaches a high uptake capacity of 0.28 g g−1 at 25 °C with a low hysteresis loop. Moreover, the gram‐scale COF‐W3 retains its high performance, which renders it more attractive in water harvesting. This work demonstrates the feasibility of this nitrogen incorporation strategy to acquire high‐performance COFs as water harvesters in the future.
Photo/electrocatalytic Reduction of CO2 to C2+ Products on MOF‐Based Catalysts
Authors: Guo Fan , Zhao Ye‐Fan , Li Rui‐Xia , Xu Huan , Sun Wei‐Yin
Published: September 2023

Efficient conversion of CO2 to valuable fuels is a desired approach to reduce global warming effect and remit sustained fossil fuel demand. Metal–organic frameworks (MOFs), a class of crystalline porous materials with unique features, have been widely studied for potential applications in varied fields. Recently, photo/electrocatalytic reduction of CO2 to two or more carbons (C2+) products has attracted extensive attention because of their higher market values than one carbon (C1). However, the major products of CO2 reduction currently are carbon monoxide, formate, or methane, which are all typical C1 products. Generally, for photocatalytic reduction of CO2 system, relatively low efficiency of electron transfer with inadequate capability results sluggish kinetics of C−C coupling. And for electrocatalysis, high current densities curtail the stability, which limits selectivity towards C2+ products. In this review, we provide very latest reports that have make some breakthroughs to overcome the above difficulties in photo/electrocatalytic reduction of CO2 to C2+ products using MOF‐based materials. Special emphases are given on design strategies of synthetic MOF‐based catalysts and the mechanisms of catalytic CO2 to C2+ products. The challenges and prospects of photo/electrocatalytic reduction of CO2 to C2+ products associated with MOF‐based materials are also discussed.
An upper Minkowski dimension estimate for the interior singular set of area minimizing currents
Authors: Skorobogatova Anna
Published: September 2023

We show that for an area minimizing m‐dimensional integral current T of codimension at least two inside a sufficiently regular Riemannian manifold, the upper Minkowski dimension of the interior singular set is at most . This provides a strengthening of the existing ‐dimensional Hausdorff dimension bound due to Almgren and De Lellis & Spadaro. As a by‐product of the proof, we establish an improvement on the persistence of singularities along the sequence of center manifolds taken to approximate T along blow‐up scales.
Novel Triangulenes: Computational Investigations of Energy Thresholds for Photocatalytic Water Splitting
Authors: Curtis Kevin , King Corban , Odoh Samuel O.
Published: September 2023

Organic materials with Inverted Singlet‐Triplet (INVEST) gaps are interesting for their potential use in photocatalytic small molecule transformations such as the entirely solar‐driven water splitting reaction. However, only a few INVEST emitters are thermodynamically able to split water requiring a first singlet excited dark state, S1, above 1.27 or 1.76 eV, and absorption near solar the maximum, 2.57 eV. These requirements and the INVEST character are key for achieving a long‐lived photocatalyst for water splitting. The only known INVEST emitters that conform to these criteria are large triangular boron carbon nitrides with unknown synthesis pathways. Using ADC(2), a quantum‐mechanical method, we describe three triangulenes. 3 a is a cyano azacyclopenta[cd]phenalene derivative while 3 b and 3 c are cycl[3.3.3]azine derivatives. 3 b has a previously undescribed disulfide bridge. Overall, 3 a fulfills requirements for photocatalytic four‐electron reduction of water while the S1 states of 3 b and 3 c are likely slightly low for the two‐electron reduction process. By analyzing impacts of ligands, we find that there are guidelines describing how S1‐S5 energies and oscillator strengths, T1 energies, and ΔES1T1 gaps are affected, requiring deep‐learning algorithms for which studies will be presented by us in due time. The impact of ground‐state geometries, solvation effects, as well as reduced‐cost ADC(2) algorithms on our findings are also discussed.
Mechanical Properties and Nanoindentation Size Effects of YAG Crystals with Different Crystal Faces
Authors: Ma Rongguo , Zhang Qingli , Zhang Rui , Gao Jinyun , Sun Guihua , Dou Renqin , Han Song , Chen Zhao , Wang Xiaofei , Zhang Deming , Sun Yu , Liu Wenpeng
Published: September 2023

In this study, the anisotropic mechanical properties of YAG crystal (100), (110), and (111) crystal faces are investigated by nanoindentation experiments. The load‐displacement curves, hardness (H) and elastic modulus (E) are obtained for each crystal face at different maximum loads. The loading curves of the three crystal faces showed displacement mutations, which are caused by microcracks during indentation of the indenter. The H and E of three crystal faces dropped as the indentation depth increased, obviously indicating indentation size effect (ISE). The H and E magnitude sequence of the three crystal faces is: (110) > (111) > (100). The surface energy is calculated by the Cambridge Serial Total Energy Package (CASTEP) program to explain the experimental phenomenon that the hardness and elastic modulus of the three crystal faces are different. Using the Nix‐Gao model to fit the Hardness‐indentation depth data, the hardness H0 of the (100), (110), and (111) crystal faces without strain gradient effect are obtained as 12.978, 15.61, and 15.432 GPa, respectively, which can be used as a reference value for the hardness of YAG crystals. The characteristic lengths h* of (100), (110), and (111) crystal faces are 730.545, 362.049, and 375.196 nm, respectively.
A five‐level common‐ground inverter with step‐up/step‐down dual‐mode operation for transformerless grid‐connected PV application
Authors: Grigoletto Felipe B. , Cedieu Sound , Chaves Diego B. , Sing Lee Sze , Siwakoti Yam P.
Published: September 2023

Step‐up multilevel inverters with common‐ground feature are attractive for transformerless photovoltaic systems. However, their performance deteriorates at step‐down voltage range. Considering a five‐level inverter with double voltage gain, the number of output voltage levels decreases from 5 to 3 for a modulation index smaller than 0.5, declining the quality of the output currents. This paper proposes a new dual‐mode five‐level common‐grounded inverter with a reduced number of switches. The proposed topology has the ability to operate as step‐up or step‐down making it well suited for application with wide input voltage range. The proposed inverter consists of five unidirectional switches, one bidirectional switch, two diodes, and two capacitors. In addition, the description of the topology, the design guidelines, and a comparison among the main topologies are given in detail. Experimental results are obtained to attest the practicability of the proposed solution.
A bipolar junction transistor EMC modeling method based on physical characteristic measurement and simplex optimization
Authors: Pan Zeyu , Zhang Yu , Ren Dan , Yang Jinsheng , Nie Bao‐Lin , Du Pingan
Published: September 2023

Bipolar junction transistors (BJTs) are widely used in various electronic systems, and the establishment of the electromagnetic compatibility (EMC) model for BJTs is crucial for EMC analysis of these systems, such as high‐frequency circuits. In this paper, a BJT EMC model that satisfies both functionality and EMC analysis requirements was established based on physical characteristic measurement. First, comprehensive and systematic methods for measurement and extracting SPICE parameters based on physical BJTs are presented, including a proposed curve‐fitting calculation method for extracting barrier capacitance parameters. Second, an analysis of the impact of major BJT electrical characteristics parameters was conducted, leading to the identification of important model parameters affecting BJT functionality and EMC. Finally, the primary BJT model was optimized using the simplex method, and a method for EMC analysis and verification of the BJT model was presented. The experimental and simulation results are in good agreement, and the established model meets the accuracy requirements for both EMC and functionality. Therefore, the proposed method is feasible and suitable for the EMC modeling of BJTs.
Mate‐guarding success depends on male investment in a butterfly
Authors: Gór Ádám , Lang Zsolt , Pásztor Kata , Szigeti Viktor , Vajna Flóra , Kis János
Published: September 2023

Males of many insects, including butterflies, produce mate‐guarding devices, such as mating plugs, to prolong guarding and prevent future female matings in the male's absence. In a few butterflies, large external mate‐guarding devices, that is, sphragides, occur. Gór et al. (Behaviour, 160, 2023 and 515−557) found conspicuously large size and morphological variation of mate‐guarding devices within a single population of the potentially polyandrous Clouded Apollo (Parnassius mnemosyne, L.) butterfly. They termed the externally visible male‐produced devices as Copulatory opening APpendices (CAP) consisting of small devices, termed small CAPs and the much larger shield (i.e. sphragis). Our aim was to reveal CAP replacement dynamics within females during their lifetime and to understand how male investment into small CAPs or shields was (i) related to CAP persistence on the female, that is securing paternity, (ii) associated with female quality, measured as size and (iii) with actual adult sex ratio. We investigated a univoltine Clouded Apollo population to estimate CAP replacement risks, using multistate survival models, in an extensive observational study through 6 years based on mark‐recapture. Shields were the most frequent mate‐guarding devices and were more persistent than small CAPs, often lasting for life, excluding future matings. Thus, most females bearing a shield were deprived of postcopulatory female choice, and the genetic variance in their offspring could be reduced compared to those bearing small CAPs, thus mating more often. The ratio of shields to all CAPs gradually decreased towards the end of the flight period. Males were more prone to produce a shield when mating females with wider thoraces and when the ratio of males (i.e. competition) was higher in the population. To our best knowledge, this is the first quantitative study to investigate potential factors on which male investment in mate‐guarding devices may depend, and how the variation in these devices impacts CAP persistence on females.
Application of a fish habitat model to assess habitat fragmentation using high flow and sediment transport in the Rumei Dam in Lancang River (China)
Authors: Yang Ge , Bao Meixia , Cong Nan , Kattel Giri , Li Yike , Xi Yuqian , Wang Yihang , Wang Qianqian , Yao Weiwei
Published: September 2023

Dam construction and operation can result in serious disturbances to the downstream flow regime and fluvial process, river morphology and the river's ecological condition worldwide. To understand the effects of discharge and sedimentation on fish habitats and ecosystems, an ecohydraulic approach was applied to one of the mega hydropower schemes in the downstream Lancang River (Tibet). The approach comprised a dam operation module with high flow and sediment transport and the application of a dynamic fish habitat model for assessing habitat fragmentation of two targeted fish species: Schizothorax prenanti (S. prenanti) and Schizothorax davidi (S. davidi). The hydrodynamics of the river system and the assessed fish habitat show a significant impact of dam construction and operation on the downstream riverine ecosystem, in which fish habitats were found rapidly deteriorated with the destruction of feeding and reproductive grounds. To improve fish habitat after dam construction, the sediment supplement was applied to the river and shown to be a useful restoration strategy, which recovers the habitat fragmentation of target fish. Our model not only is useful to predict dam operation impacts on the Lancang River's ecological status but also shows great potential in mitigating hydropower‐induced environmental impacts and developing river conservation guidelines worldwide.
Direct Access to 1,3‐Oxathiolan‐5‐ones through (3+2)‐Cycloaddition of Thioketones and Acetylenedicarboxylic Acid
Authors: Sachse Florian , Schneider Christoph
Published: September 2023

Herein, we report a novel protocol for the direct synthesis of 1,3‐oxathiolan‐5‐ones based on the (3+2)‐cycloaddition between thioketones and acetylenedicarboxylic acid. The products were obtained in a one‐pot reaction within short reaction times and in typically very good yields. The product structure was confirmed by X‐ray diffraction analysis.
Development of a bio‐inspired magnetic nanocomposite synthesized through semi‐covalent imprinting for electrochemical determination of cholesterol in water samples
Authors: Peixoto Lins Eduardo , Effting Luciane , Maria Effting Letícia , Del Pilar Taboada Sotomayor Maria , Gava Segatelli Mariana , Bail Alesandro , Ricardo Teixeira Tarley César
Published: September 2023

Fecal pollution in aquatic environments by analysis of fecal coliforms along with the determination of sterol compounds, such as cholesterol (CHO) has been extensively investigated. Thus, the development of an easier, cheaper, selective, and sensitive method for CHO monitoring in aquatic environments can be a valuable tool in contributing to the analysis of fecal pollution mainly in developing countries. In the present study, a voltammetric method aiming at CHO determination in aqueous media based on a magnetic molecular imprinted polymer (MMIP) sensor is proposed. The MMIP was synthesized on the surface of silica‐coated magnetite, using CHO as a template covalently bound to 3‐(triethoxysilyl)propyl isocyanate (ICPTES). A suspension of MMIP was prepared in ethanol and used to modify a graphite‐epoxy composite magneto‐actuated electrode (m‐GEC). The indirect CHO determination was based on the decrease in the current of [Fe(CN)6]3−/4− redox probe in the presence CHO. Under optimized experimental conditions (Britton‐Robinson buffer 0.01 mol L−1 at pH 7.0), the parameters of square wave voltammetry were optimized through the Doehlert matrix (amplitude of 111.2 mV, potential increase of 10.8 mV and frequency of 5.54 Hz). An analytical curve ranging from 0.51 up to 11.0 μmol L−1 was obtained with a limit of detection of 0.15 μmol L−1. The developed method was applied to the analysis of the lake water sample, and the accuracy of the method was confirmed by HPLC‐DAD as a reference technique.
Higher‐order derivative spectroelectrochemical measurement of ferrocene dissolved into water‐in‐salt electrolyte solution
Authors: Kishioka Shinya
Published: September 2023

Ferrocene was dissolved in a water‐in‐salt solution containing a high concentration of a supporting electrolyte. Open‐circuit potential, electronic absorption spectra, and cyclic voltammetry revealed that a part of the dissolved ferrocene existed as ferrocenium ions. Spectroelectrochemical measurements and higher‐order derivative spectra revealed that the water‐in‐salt electrolyte aqueous solution is an excellent medium for electrochemical and spectroscopic measurement of redox‐active species with water insolubility.
Inland thinning of Byrd Glacier, Antarctica, during Ross Ice Shelf formation
Authors: Stutz Jamey , Eaves Shaun , Norton Kevin , Wilcken Klaus M. , Moore Claudia , McKay Rob , Lowry Dan , Licht Kathy , Johnson Katelyn
Published: September 2023

Geomorphological records of past ice sheet change offer the opportunity to examine their centennial‐scale response to changing boundary conditions, which are not adequately captured in the satellite record. Here, we present the first reconstruction of ice surface lowering at Byrd Glacier, the largest outlet glacier of the Transantarctic Mountains. Using surface exposure ages from glacial erratic cobbles collected in two vertical transects along the Lonewolf Nunataks, we find the initial emergence of this set of nunataks occurred at ~15 ka, with a rapid pulse of thinning at ~8 ka. We compare our glacier thinning profiles with modelled ice sheet thickness and grounding line histories from two model ensembles to identify key processes responsible for ice sheet change. All model runs from the two ensembles predict grounding line retreat and inland thinning to occur in one rapid step from Last Glacial Maximum to present, in line with marine geology records, our exposure age data and derived glacier thinning rates. Experiments best matching the glacial thickness constraints, reconstructed from the surface exposure data, have faster basal sliding (i.e., promote greater sliding rates resulting in thinner ice). However, experiments best matching the timing and rapid rate of ice thinning derived from the same surface exposure data have higher basal friction. This apparent change in the modelled basal sliding regime, from when the ice surface is at maximum thickness, to the rapid thinning at ~8 ka, occurs as the grounding line retreats towards the Byrd Glacier and Ross Ice Shelf forms during the Holocene. This past context has implications for the stability of the modern grounding line of Byrd Glacier, which is characterised by high basal melt rates at the terminus—a process that has the potential to propagate glacier thinning far inland, impacting the overall (in)stability of the Byrd Glacier and Ross Ice Shelf.
Extreme cold‐weather battery thermal management for optimal electric vehicle performance
Authors: Ruhatiya C. , Gandra Ruthvik , Kondaiah P. , Garg Akhil , Tibrewala Himanshu
Published: September 2023

Battery thermal management system (BTMS) may seem a very standard term, but it is the lifeline of an efficient battery pack module in various vehicles and standalone stationary energy storage systems. The majority of the available literature is aimed toward temperature optimization of batteries in hotter climatic conditions. The cold temperature‐related effects on battery packs have amplifying implications on the battery cycle life and operational capacity. The electric vehicles operating in cold temperature environment face sudden fluctuations in temperatures across the battery pack module due to large temperature gradient between battery surface and internals, and ambient conditions. This work focuses on addressing the problem related to sudden drop in cell temperatures when battery operations are switched off (cold stop conditions). The phase change materials (PCMs) based passive BTMS system is evaluated in this study. The BTMS with different designs and PCMs are modeled in Multiphysics environment and simulated close to extreme cold temperature environments. The formulated models are then used for comparing commercially available PCMs material for their efficiency and viability. The main parameter evaluated was rate of temperature decrease, it was observed that organic mixture‐type PCMs are best suited for cold temperature application.