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Developing high‐performance platinum (Pt) single atom catalyst with maximum metal‐atom‐utilization efficiency is of significance for water electrolysis, which demonstrates enormous potentials toward hydrogen evolution reaction (HER). In addition to stably immobilizing Pt single atoms on a support material, it is highly desired to elaborately tailor their coordination environments for achieving optimized HER performance. In this work, a general strategy is reported to develop advanced catalysts with Pt single atoms immobilized on conjugated polymers, where their coordination environments and HER activities can be readily tailored by adjusting the cation‐π interactions formed between the Pt single atoms and conjugated polymers. For the proof‐of‐concept study, polypyrrole (PPy), polyfuran (PFu), and polythiophene (PTh) with analogous molecular structures are investigated, where the N, O, and S heteroatoms in PPy, PFu, and PTh can affect their π domains and induce different cation‐π interactions. Experimental and theoretical studies both suggest that the HER performance of the resulting catalysts follows the trend of Pt1‐PTh < Pt1‐PFu < Pt1‐PPy, which shows a correlation with their cation‐π interactions. Moreover, by utilizing the microstructure‐tailorable property of conjugated polymers, PPy aerogel with enhanced specific surface area are prepared to support Pt single atoms, achieving substantial HER performance improvement. [ABSTRACT FROM AUTHOR]

In this study, several 3-dimensional (3-D) parameter estimation and localization algorithms for wireless near-field (NF) sources are proposed employing the uniform circular array (UCA) structure. In the single-base-station case, the algebraic relation is demonstrated between the azimuth angle under the far-field (FF) assumption and the actual NF source firstly. Secondly, two groups of antenna pairs are selected with distances less than half the wavelength, which are called short baselines in the interferometer method. The foregoing short-baseline method is qualified to localize an NF source. In addition, a long-baseline method is also proposed with further research. Two groups of antenna pairs with distances greater than half the wavelength are selected as two long baselines. In the multiple-base-stations case, another two novel algorithms are also proposed. The first one is the centroid algorithm, which is based on the centroid calculation of three estimated source locations. And the second one is the perpendicular foot algorithm, which takes the perpendicular foot within three estimated source locations as the final positioning location. Simulation results illustrate that the proposed algorithms can achieve higher localization accuracy than the conventional 3-D Root MUSIC method. Moreover, the long-baseline method performs better than the short-baseline method. And it is also shown that the proposed perpendicular foot algorithm shows better performance than the proposed centroid algorithm. [ABSTRACT FROM AUTHOR]

Biomass waste, which is biodegradable and vastly underutilized, is generated in huge quantities worldwide. Forestry and agricultural biomass wastes are notable for their wide availability, high yield, biodegradability, and recyclability. The accumulation of these wastes not only occupies valuable land but causes serious environmental pollution, which can ultimately harm human health. Therefore, leveraging scientific technology to convert forestry and agricultural bio-waste into bioenergy and other valuable products is crucial. In this paper, common forestry and agricultural bio-waste such as straw, rice husks, livestock manure, tree branches, sawdust, and bioenergy (bioethanol, biogas, biodiesel, biohydrogen) were selected as keywords, with the theme of green and efficient utilization. This paper provides a comprehensive review of the sources of biomass waste, existing recycling technologies, and the potential of forestry and agricultural bio-waste as material additives and for conversion to biomass energy and other derivatives, along with future recycling prospects. [ABSTRACT FROM AUTHOR]

Android malware is becoming more common, and its invasion of smart devices has brought immeasurable losses to people's lives. Most existing Android malware detection methods extract Android features from the original application files without considering the high-order hidden information behind them, but these hidden information can reflect malicious behaviors. To solve this problem, this paper proposes Z2F, a detection framework based on multidimensional Android feature extraction and graph neural networks for Android applications. Z2F first extracts seven types of Android features from the original Android application and then embeds them into a heterogeneous graph. On this basis, we design 12 kinds of meta-structures to analyze different semantic spaces of heterogeneous graphs, mine high-order hidden semantic information, and adopt a multi-layer graph attention mechanism to iteratively embed and update information. In this paper, a total of 14429 Android applications were detected and 1039726 Android features were extracted, with a detection accuracy of 99.7%. [ABSTRACT FROM AUTHOR]

This study aims to investigate the impact of dietary supplementation with selenium yeast (SeY) and glycerol monolaurate (GML) on the transfer of antioxidative capacity between the mother and fetus during pregnancy and its underlying mechanisms. A total of 160 sows with similar body weight and parity of 3–6 parity sows were randomly and uniformly allocated to four groups (n = 40) as follows: CON group, SeY group, GML group, and SG (SeY + GML) group. Animal feeding started from the 85th day of gestation and continued to the day of delivery. The supplementation of SeY and GML resulted in increased placental weight and reduced lipopolysaccharide (LPS) levels in sow plasma, placental tissues, and piglet plasma. Furthermore, the redox balance and inflammatory markers exhibited significant improvements in the plasma of sows fed with either SeY or GML, as well as in their offspring. Moreover, the addition of SeY and GML activated the Nrf2 signaling pathway, while downregulating the expression of pro-inflammatory genes and proteins associated with inflammatory pathways (MAPK and NF-κB). Vascular angiogenesis and nutrient transportation (amino acids, fatty acids, and glucose) were upregulated, whereas apoptosis signaling pathways within the placenta were downregulated with the supplementation of SeY and GML. The integrity of the intestinal and placental barriers significantly improved, as indicated by the increased expression of ZO-1, occludin, and claudin-1, along with reduced levels of DLA and DAO with dietary treatment. Moreover, supplementation of SeY and GML increased the abundance of Christensenellaceae_R-7_group, Clostridium_sensus_stricto_1, and Bacteroidota, while decreasing levels of gut microbiota metabolites LPS and trimethylamine N-oxide. Correlation analysis demonstrated a significant negative relationship between plasma LPS levels and placental weight, oxidative stress, and inflammation. In summary, dietary supplementation of SeY and GML enhanced the transfer of antioxidative capacity between maternal-fetal during pregnancy via gut–placenta axis through modulating sow microbiota composition. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrogen oxidation reaction (NOR) offers an efficient and sustainable approach for conversion of widespread nitrogen (N2) into high‐value‐added nitrate (NO3−) under mild conditions, representing a promising alternative to the traditional approach that involves harsh Haber–Bosch and Ostwald oxidation processes. Unfortunately, due to the weak absorption/activation of N2 and the competitive oxygen evolution reaction, the kinetics of NOR process is extremely sluggish accompanied with low Faradaic efficiencies and NO3− yield rates. In this work, an oxygen‐vacancy‐enriched perovskite oxide with nonstoichiometric ratio of strontium and ruthenium (denoted as Sr0.9RuO3) was synthesized and explored as NOR electrocatalyst, which can exhibit a high Faradaic efficiency (38.6 %) with a high NO3− yield rate (17.9 μmol mg−1 h−1). The experimental results show that the amount of oxygen vacancies in Sr0.9RuO3 is greatly higher than that of SrRuO3, following the same trend as their NOR performance. Theoretical simulations unravel that the presence of oxygen vacancies in the Sr0.9RuO3 can render a decreased thermodynamic barrier toward the oxidation of *N2 to *N2OH at the rate‐determining step, leading to its enhanced NOR performance. [ABSTRACT FROM AUTHOR]

Ciphertext policy–attribute-based encryption (CP-ABE), which provides fine-grained access control and ensures data confidentiality, is widely used in data sharing. However, traditional CP-ABE schemes often choose to outsource data to untrusted third-party cloud service providers for storage or to verify users' access rights through third parties, which increases the risk of privacy leakage and also suffers from the problem of opaque permission verification. This paper proposes an access control scheme based on blockchain and CP-ABE, which is based on multiple authorization centers and supports policy updating. In addition, blockchain technology's distributed, decentralized, and tamper-proof features are utilized to solve the trust crisis problem in the data-sharing process. Security analysis and performance evaluation show that the proposed scheme improves the computational efficiency by 18%, 26%, and 68% compared to previous references. The proposed scheme also satisfies the indistinguishability under chosen-plaintext attack (IND-CPA). [ABSTRACT FROM AUTHOR]

Abstract ZnO/HfO2:Eu nanocables were prepared by radio frequency sputtering with electrospun ZnO nanofibers as cores. The well-crystallized ZnO/HfO2:Eu nanocables showed a uniform intact core–shell structure, which consisted of a hexagonal ZnO core and a monoclinic HfO2 shell. The photoluminescence properties of the samples were characterized. A white-light band emission consisted of blue, green, and red emissions was observed in the nanocables. The blue and green emissions can be attributed to the zinc vacancy and oxygen vacancy defects in ZnO/HfO2:Eu nanocables, and the yellow–red emissions are derived from the inner 4f-shell transitions of corresponding Eu3+ ions in HfO2:Eu shells. Enhanced white-light emission was observed in the nanocables. The enhancement of the emission is ascribed to the structural changes after coaxial synthesis.

Aiming at the anti-collision performance of SS-grade concrete guardrail of Chinese highway bridges, the nonlinear dynamic simulation of collision is carried out. On this basis, aiming at the defects of rigid guardrail, a rigid and flexible composite double-layer guardrail is proposed, and its anti-collision performance is evaluated. The vehicle factor analysis shows that the energy absorbed by the guardrail system, crash force, guardrail damage and reinforcement stress range increase with the increase of vehicle speed and impact angle. The effect of concrete grade on improving the anti-collision performance of guardrails is limited. It is not that the higher the strength grade, the better the effect. Compared with concrete guardrail, the vehicle deformation energy of double-layer guardrail system is only 59.1% of that of concrete guardrail system. This shows that the deformation of the vehicle is more serious when the vehicle hits the concrete guardrail, and the damage to the driver and passenger is greater, while the double-layer guardrail can improve the safety of the driver and passenger. The crash force of double-layer guardrail is reduced, so the impact suffered by passengers is reduced and the double-layer guardrail has good buffering effect. [ABSTRACT FROM AUTHOR]