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Since the discovery in 2000, conversion‐type materials have emerged as a promising negative‐electrode candidate for next‐generation batteries with high capacity and tunable voltage, limited by low reversibility and severe voltage hysteresis. Heterogeneous construction stands out as a cost‐effective and efficient approach to reducing reaction barriers and enhancing energy density. However, the second term introduced by conventional heterostructure inevitably complicates the electrochemical analysis and poses great challenges to harvesting systematic insights and theoretical guidance. A model cell is designed and established herein for the conversion reactions between Na and TMSA−SnO2, where TMSA−SnO2 represents single atom modification of eight different 3d transition elements (V, Cr, Mn, Fe, Co, Ni, Cu or Zn). Such a model unit fundamentally eliminates the interference from the second phase and thus enables independent exploration of activation manifestations of the heterogeneous architecture. For the first time, a thermodynamically dependent catalytic effect is proposed and verified through statistical data analysis. The mechanism behind the unveiled catalytic effect is further elucidated by which the active d orbitals of transition metals weaken the surface covalent bonds and lower the reaction barriers. This research provides both theoretical insights and practical demonstrations of the advanced heterogeneous electrodes. [ABSTRACT FROM AUTHOR]

Preparing asymmetric pervaporation membranes is a kind of promising method to enhance pervaporation membrane flux. Hydrophobic PVDF polymer can be used to prepare asymmetric pervaporation membranes, but its separation factor is relatively low. In this work, to improve the performance of PVDF membrane pervaporation, PDMS polymer was added to the PVDF membrane, and asymmetric PDMS/PVDF permeable membranes were prepared by the non‐solvent induced phase separation (NIPS) method. The effects of mass ratios of PDMS to PVDF on the membrane structures and the membrane properties were characterized by SEM, XRD, FTIR, TGA, water contact angle and mechanical strength. The results showed that the ratios of the PDMS: PVDF affect its phase‐separation behavior. As the addition of PDMS increased, the finger‐like pores on the membrane section gradually became longer, the upper surface changed from less porous to porous structure, and the lower surface structure changed from interconnected flocculent structure to porous, and the best structure of the blend membrane was achieved when the PDMS: PVDF mass ratio was 1 : 5. Therefore, the membrane had the best separation performance in separating 15 wt. % ethanol aqueous solution with a permeate total flux of 273.65 g/(m2 h) and a separation factor of 9.09 when the mass ratio of PDMS: PVDF was 1 : 5. [ABSTRACT FROM AUTHOR]

In this study, we synthesized and characterized a new Co(II)‐based coordination polymer, denoted as {[Co(HL)(dpa)]·H2O}n (1), derived from the H3L ligand and dpa co‐ligand. Single crystal X‐ray diffraction revealed that 1 forms a two‐dimensional (2D) layer and a three‐dimensional (3D) supramolecular structure via hydrogen bonding interactions. Presence of carboxylic acid groups in 1 was confirmed by X‐ray crystallography, prompting investigation into its proton transport properties. Additionally, electrostatic potential surface and nucleophilic index analyses were conducted to simulate potential proton transfer pathways. Furthermore, we prepared nine modified encapsulated materials using 1 as the base material (SDA@1, APH@1, APY@1, TA@1, BA@1, DIC@1, IDZ@1, SCA@1, and TYD@1), and tested their proton conductivity and activation energy compared to pure Nafion membrane and 1, analyzing the influence of different small molecule structures on proton conductivity. Comparative analysis revealed that only SDA@1 exhibited enhanced proton conductivity and reduced activation energy at 303 K, with an improvement rate of 220.8%. We hope that the methods presented herein can provide valuable insights for the design and development of high‐performance proton‐conducting materials, as well as for the exploration of proton conduction mechanisms. [ABSTRACT FROM AUTHOR]

The investigation of multifunctional bright materials is a popular research topic. The first report of the Bi3+, Tb3+, and Eu3+ triple‐doped garnet‐derived structure Lu2Mg2Al2Si2O12 phosphor is presented in this study. The energy transfer system was constructed with unique ultraviolet (UV) emission of Bi3+ ions, which allows phosphor to be used for temperature sensing with self‐calibration capability, Sa = 0.26% (148 K) and 0.56% (98 K), Sr = 0.15% (98 K), and 0.21% (148 K), indicating a high sensitivity in the low‐temperature region. Tb3+ and Eu3+ ions with better thermal stability under 325 nm excitation were chosen to achieve higher pressure sensing performance, the sensitivity was calculated by fluorescence intensity ratio technique and has maximum sensitivities of up to 0.1887 (SPa) and 0.1621 G/Pa (SPr). This provides a new idea for the ensuing design of brand‐new phosphors for optical pressure sensing. This study provides a new perspective on the versatile applications of phosphors. [ABSTRACT FROM AUTHOR]

Background: Large‐scale observational studies have summarized transfusion practice using traditional measures of central tendency (e.g., the mean hemoglobin concentration at the time of transfusion). However, the mean hemoglobin concentration fails to identify specific hemoglobin concentration thresholds that drive practice. In the following brief report, we propose a novel measure of "practice discontinuity" that identifies specific practice‐defining hemoglobin thresholds. Study Design and Methods: We used the PINC AI Database (2016–2022) to identify adult patients admitted to an intensive care unit with at least one hemoglobin concentration measurement. For each day that hemoglobin was measured, we identified whether the patient received a red blood cell transfusion using hospital charge codes. We defined the "practice discontinuity" measure as the hemoglobin concentration at which there was the largest increase in transfusion use going from a higher to an incrementally lower hemoglobin concentration. We also calculated the mean and median pretransfusion hemoglobin concentrations. Results: We identified 1,298,367 patients and 4,905,839 patient‐days for inclusion. RBC transfusion occurred in a total of 530,654 (10.8%) patient‐days. The overall pre‐transfusion mean and median hemoglobin concentrations were 8.4 and 8.0 g/dL, respectively. The practice discontinuity measure identified 7.0 g/dL as the hemoglobin concentration at which transfusion use increased the most, from 46.6% of patient‐days at a concentration of 7.0 g/dL to 74.8% of patient‐days at a concentration of 6.9 g/dL. Discussion: We propose that future studies of red blood cell transfusion practice consider inclusion of the practice discontinuity measure to more fully summarize clinical practice. [ABSTRACT FROM AUTHOR]

The flexural behavior of beams strengthened with GFRP bars and high‐performance fiber‐reinforced concrete (HPFRC) was investigated in this paper. The four‐point flexural response of one reference beam and four beams strengthened with high‐performance fiber‐reinforced concrete was investigated by experimental research and theoretical calculation. The experimental and theoretical data (strain, load, etc.) are discussed. Parameters varied included the strengthening scheme (bottom‐side strengthening and three‐side strengthening) and the type of high‐performance fiber‐reinforced concrete (engineered cementitious composite [ECC] and ultra‐high‐performance concrete [UHPC]). The results showed that the cracking load and ultimate load of beams strengthened with UPFRC material were 31.3%–170% and 9.6%–20.7% higher, respectively, relative to the reference beam. Beams with three‐side strengthening (without interfacial debonding) had higher ultimate load, smaller crack width, and better durability relative to beams with bottom‐side strengthening. The UHPC layer was more effective in increasing the ultimate bearing capacity, and ECC strengthening layer was more effective in inhibiting cracking development of beams. Based on the experimental results, a model was proposed to predict the ultimate bearing capacity of beams strengthened with high‐performance fiber‐reinforced concrete, which could provide good agreement between the experimental and predicted results. [ABSTRACT FROM AUTHOR]