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Abstract Compositional complex alloys, including high and medium‐entropy alloys (HEAs/MEAs) have displayed significant potential as efficient electrocatalysts for the oxygen evolution reaction (OER), but their structure‐activity relationship remains unclear. In particular, the basic question of which crystal facets are more active, especially considering the surface reconstructions, has yet to be answered. This study demonstrates that the lowest index {100} facets of FeCoNiCr MEAs exhibit the highest activity. The underlying mechanism associated with the {100} facet's low in‐plane density, making it easier to surface reconstruction and form amorphous structures containing the true active species is uncovered. These results are validated by experiments on single crystals and polycrystal MEAs, as well as DFT calculations. The discoveries contribute to a fundamental comprehension of MEAs in electrocatalysis and offer physics‐based strategies for developing electrocatalysts.

ABSTRACTIdentification and the time since deposition (TsD) estimation of body fluid stains from a crime scene could provide valuable information for solving the cases and are always difficult for forensics. Microbial characteristics were considered as a promising biomarker to address the issues. However, changes in the microbiota may damage the specific characteristics of body fluids. Correspondingly, incorrect body fluid identification may result in inaccurate TsD estimation. The mutual influence is not well understood and limited the codetection. In the current study, saliva, semen, vaginal secretion, and menstrual blood samples were exposed to indoor conditions and collected at eight time points (from fresh to 30 days). High-throughput sequencing based on the 16S rRNA gene was performed to characterize the microbial communities. The results showed that a longer TsD could decrease the discrimination of different body fluid stains. However, the accuracies of identification still reached a quite high value even without knowing the TsD. Correspondingly, the mean absolute error (MAE) of TsD estimation significantly increased without distinguishing the types of body fluids. The predictive TsD of menstrual blood reached a quite low MAE (1.54 ± 0.39 d). In comparison, those of saliva (6.57 ± 1.17 d), semen (6.48 ± 1.33 d), and vaginal secretion (5.35 ± 1.11 d) needed to be further improved. The great effect of individual differences on these stains limited the TsD estimation accuracy. Overall, microbial characteristics allow for codetection of body fluid identification and TsD estimation, and body fluids should be identified before estimating TsD in microbiome-based stain analyses.IMPORTANCEEmerged evidences suggest microbial characteristics could be considered a promising tool for identification and time since deposition (TsD) estimation of body fluid stains. However, the two issues should be studied together due to a potential mutual influence. The current study provides the first evidence to understand the mutual influence and determines an optimal process for codetection of identification and TsD estimation for unknown stains for forensics. In addition, we involved aged stains into our study for identification of body fluid stains, rather than only using fresh stains like previous studies. This increased the predictive accuracy. We have preliminary verified that individual differences in microbiotas limited the predictive accuracy of TsD estimation for saliva, semen, and vaginal secretion. Microbial characteristics could provide an accurate TsD estimation for menstrual blood. Our study benefits the comprehensive understanding of microbiome-based stain analyses as an essential addition to previous studies.

Environmental responsibility and economic benefits have promoted the development of closed-loop supply chains (CLSCs), and shortages and channels are considered to be two important issues in a CLSC. This paper explores the ordering and channel decisions in a CLSC with new and differentiated remanufactured products; considers the price and sales-effort-dependent demands, as well as the proportion of emergency orders determined by emergency order costs and backorder losses; and establishes integrated and decentralized CLSC game models. We introduce a stochastic sales effort, which affects two types of products. The numerical results show that sales effort and the order quantity of new and remanufactured products exhibit concave and convex functions, respectively. The upper limit of sales effort has a greater impact on supply chain decisions. High sales efforts can serve as a means of coordinating dispersed supply chains. Moreover, in different cases, the decisions of an integrated channel are better than those of a decentralized channel. Finally, whether the supply chain adopts an emergency order strategy depends on the relative cost of emergency orders and out-of-stock costs. According to this research, some management insights are also provided.

High-entropy alloys (HEAs) have emerged as a promising platform for designing efficient electrocatalysts; however, the relationship between their structure and activity has not yet been clearly established. In particular, the influences of crystalline defects, such as grain boundaries (GBs), on activity and stability remain unclear. This study demonstrates the impacts of GBs on the oxygen evolution reaction (OER) activity in the FeCoCrNi HEA. We observe a logarithmic dependence of OER performance on mean grain size, spanning 3 orders of magnitude, as measured by evaluators like overpotential and Tafel slope. Spatially resolved microscopic imaging of activated samples indicates that the GBs undergo substantial reconstructions and they are enriched with the in situ formed metal oxides (M-O, M = Fe, Co, Ni) and the amorphous regions. By comparing with simple metals, we reveal a “high-entropy effect,” i.e., HEAs exhibit greater tolerance towards the grain refinements, which explains their activity both in bulk samples and nanoparticles. These findings offer physics-informed strategies for developing HEA electrocatalysis.

This article, titled "On the Perception of a Chinese American English Accent," is written by Chunsheng Yang, Gao Niu, and Han Luo. Chunsheng Yang is an associate professor of Chinese and applied linguistics at the University of Connecticut, with research areas including Chinese phonetics, phonology, second language acquisition, Chinese sociolinguistics, and Chinese pedagogy. Gao Niu is an assistant professor in actuarial science at Bryant University, specializing in big data analytics application in the insurance industry. Han Luo is an associate professor of Chinese at Lafayette College, focusing on Chinese linguistics, cognitive linguistics, second language acquisition, and foreign language pedagogy. Unfortunately, the full text of the article is not available in the provided source. [Extracted from the article]

In this work, Ca-doped lithium manganese oxides Li0.98Ca0.02Mn2O4 were successfully synthesized via a facile hydrothermal method followed by calcination. The evolution of the microstructures and electrochemical performance were investigated in detail. XRD identified that pure spinel phase with the enlarged lattice constants were observed in Ca-doped samples. SEM revealed that powders had a hollow hemispherical morphology composed of stacked nanoparticles. Ca doping can improve the electrochemical performance of LiMn2O4. Galvanostatic charge-discharge tests demonstrated that Li0.98Ca0.02Mn2O4 calcined at 550°C could deliver the initial discharge capacity of 108.6 mA h/g with the capacity retention of 91.4% after 100 cycles at 2 C. The results indicate that Ca-doped LiMn2O4 is a promising cathode material. [ABSTRACT FROM AUTHOR]

Well-ordered, globally oriented composite fibers with micro/nanowire arrays of polystyrene (PS) fibers embedded in polyethylene (PE) were prepared by an iterative melt co-drawing and the bundling technique. With section-cutting of the PE/PS fiber and the dissolution of inner PS, porous PE fibers were obtained. Optical microscopy and scanning electron microscopy (SEM) showed that the distribution of pores were regular hexagonal, the diameters of the pores after the third drawing step were about 175 nm, and the spacings of pores were 1-2 micron. There was good agreement between calculated and experimental values for the pore diameters and spacings. The obtained porous template was used to prepare Cu nanowires by electrochemical deposition. SEM in combination with the energy dispersive X-ray analysis (EDX) indicated that Cu nanowires were successfully deposited in the pores of the template. Potential applications of this simple and inexpensive fabrication technology were discussed for preparing micro/nanowire arrays with highly controllable geometric parameters., INTRODUCTION Micro/nanowire arrays have attracted considerable attention owing to novel properties arising from their quasi-one-dimensional ordered structure. Many methods are used to prepare micro/nanowire arrays [1-6], such as chemical synthesis, [...]