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To comprehensively understand temperature and moisture changes in a continuous microwave rice grain drying system, this study proposes a simulation strategy that facilitates the continuous movement of rice grains. The study establishes a three‐dimensional model concerning multiple physical fields, including electromagnetism, heat, and mass transfer. It examines the effects of rice grain layer thickness and microwave intensity on the moisture and temperature of rice grains. The results indicate that the drying rate is negatively correlated with material thickness but positively correlated with temperature. The optimal thickness for the rice grain layer is 8 mm. Furthermore, both the microwave drying rate and temperature increase with microwave intensity. These findings contribute to a deeper understanding of the hydrothermal change mechanisms in rice grains during microwave drying. Practical applications: Microwave drying, as an emergent drying technology, has garnered widespread attention for its selective heating, efficient drying, energy savings, and environmental protection. Nevertheless, enhancing uniformity during the microwave heating process constitutes an important research topic in scientific research and technological applications. Numerical simulation methods can visually analyze electric field distribution, thereby optimizing microwave heating uniformity and improving drying effects. This article aims to accurately predict the continuous microwave drying time of paddy and maximize energy usage by optimizing drying thickness and microwave power parameters establishing a mathematical model for the process. The study not only provides a solid theoretical basis for microwave dryer design but also scientifically guides the continuous microwave drying of rice and other food crops. [ABSTRACT FROM AUTHOR]

The deep‐bed drying process of rice grains was investigated through numerical simulation, employing the porous medium flow field theory and the local thermal nonequilibrium method. Moisture field of rice grains described using thin‐layer equations. On this basis, the deep‐bed drying of rice grains modeled with COMSOL, and verified its plausibility. The results showed that the drying rate of rice grains was significantly accelerated when the hot air temperature was increased from 40°C to 70°C, but the inhomogeneity of rice grains temperature increased by 29.79%, 22.31%, and 17.41% for every 10°C increase. Drying grains faster with vertically arranged an angular air duct, with a 4.88% increase in drying speed in 300 min. The temperature difference between the top and the bottom of an angular air duct with a small width is smaller, about 11°C, and the heating efficiency is better at the top, by 31.28%. Practical Applications: Grain dryers are often used in high‐volume grain drying operations and it has been a great challenge to save the energy consumption of the drying process. It is necessary to use numerical simulation to design a reasonable structure of the heating section to improve the energy utilization efficiency of the heating section of the grain dryer. The numerical model proposed in this article can effectively simulate the spatial distribution of moisture content of rice under different structures of grain drying units, which can be used not only for the prediction of drying time but also for analyzing the optimal heating structure from it. A technical basis is provided for the design of grain dryers. [ABSTRACT FROM AUTHOR]

Kupffer cells (KCs) are liver‐resident macrophages involved in hepatic inflammatory responses, including nonalcoholic fatty liver disease (NAFLD) development. However, the contribution of KC subsets to liver inflammation remains unclear. Here, using high‐dimensional single‐cell RNA sequencing, we characterized murine embryo‐derived KCs and identified two KC populations with different gene expression profiles: KC‐1 and KC‐2. KC‐1 expressed CD170, exhibiting immunoreactivity and immune‐regulatory abilities, while KC‐2 highly expressed lipid metabolism‐associated genes. In a high‐fat diet–induced NAFLD model, KC‐1 cells differentiated into pro‐inflammatory phenotypes and initiated more frequent communications with invariant natural killer T (iNKT) cells. In KC‐1, interleukin (IL)‐10 expression was unaffected by the high‐fat diet but impaired by iNKT cell ablation and upregulated by iNKT cell adoptive transfer in vivo. Moreover, in a cellular co‐culture system, primary hepatic iNKT cells promoted IL‐10 expression in RAW264.7 and primary KC‐1 cells. CD206 signal blocking in KC‐1 or CD206 knockdown in RAW264.7 cells significantly reduced IL‐10 expression. In conclusion, we identified two embryo‐derived KC subpopulations with distinct transcriptional profiles. The CD206‐mediated crosstalk between iNKT and KC‐1 cells maintains IL‐10 expression in KC‐1 cells, affecting hepatic immune balance. Therefore, KC‐based therapeutic strategies must consider cellular heterogeneity and the local immune microenvironment for enhanced specificity and efficiency. [ABSTRACT FROM AUTHOR]

SUMMARY: Pear fruit stone cells have thick walls and are formed by the secondary deposition of lignin in the primary cell wall of thin‐walled cells. Their content and size seriously affect fruit characteristics related to edibility. To reveal the regulatory mechanism underlying stone cell formation during pear fruit development and to identify hub genes, we examined the stone cell and lignin contents of 30 'Shannongsu' pear flesh samples and analyzed the transcriptomes of 15 pear flesh samples collected at five developmental stages. On the basis of the RNA‐seq data, 35 874 differentially expressed genes were detected. Additionally, two stone cell‐related modules were identified according to a WGCNA. A total of 42 lignin‐related structural genes were subsequently obtained. Furthermore, nine hub structural genes were identified in the lignin regulatory network. We also identified PbMYB61 and PbMYB308 as candidate transcriptional regulators of stone cell formation after analyzing co‐expression networks and phylogenetic relationships. Finally, we experimentally validated and characterized the candidate transcription factors and revealed that PbMYB61 regulates stone cell lignin formation by binding to the AC element in the PbLAC1 promoter to upregulate expression. However, PbMYB308 negatively regulates stone cell lignin synthesis by binding to PbMYB61 to form a dimer that cannot activate PbLAC1 expression. In this study, we explored the lignin synthesis‐related functions of MYB family members. The results presented herein are useful for elucidating the complex mechanisms underlying lignin biosynthesis during pear fruit stone cell development. Significance Statement: In this study, we used WGCNA with a phylogenetic approach to obtain two candidate MYB TFs. We experimentally validated and characterized candidate transcription factors and revealed a module of PbMYB61 with PbMYB308 regulating PbLAC1 involved in the regulation of pear stone cell biosynthesis. The results presented herein are useful for elucidating the complex mechanisms underlying lignin biosynthesis during pear fruit stone cell development. [ABSTRACT FROM AUTHOR]

Summary: The anthocyanin content is an important indicator of the nutritional value of most fruits, including apple (Malus domestica). Anthocyanin synthesis is coordinately regulated by light and various phytohormones. In this study on apple, we revealed the antagonistic relationship between light and brassinosteroid (BR) signaling pathways, which is mediated by BRASSINAZOLE‐RESISTANT 1 (MdBZR1) and the B‐box protein MdCOL6.The exogenous application of brassinolide inhibited the high‐light‐induced anthocyanin accumulation in red‐fleshed apple seedlings, whereas increases in the light intensity decreased the endogenous BR content. The overexpression of MdBZR1 inhibited the anthocyanin synthesis in apple plants. An exposure to a high‐light intensity induced the degradation of dephosphorylated MdBZR1, resulting in functional impairment.MdBZR1 was identified as an upstream repressor of MdCOL6, which promotes anthocyanin synthesis in apple plants. Furthermore, MdBZR1 interacts with MdCOL6 to attenuate its ability to activate MdUFGT and MdANS transcription. Thus, MdBZR1 negatively regulates MdCOL6‐mediated anthocyanin accumulation.Our study findings have clarified the molecular basis of the integration of light and BR signals during the regulation of anthocyanin biosynthesis, which is an important process influencing fruit quality. [ABSTRACT FROM AUTHOR]

The reported work has developed a methodology of printing and curing continuous fiber‐reinforced thermosetting polymer composites (CFRTPCs) with excellent mechanical properties at low temperatures. First, to print and cure CFRTPCs at low temperatures, a thermosetting polymer system was proposed, consisting of phenol based epoxy resin and curing agent (F‐44/2E4MZ). The rheological properties of the polymer system were analyzed to determine a reasonable printing temperature. Second, the non‐linear Vyazovkin integral method was applied to establish the model‐free kinetics (MFK) of the resin system. MFK can predict the curing degree curves at the characteristic temperatures obtained by extrapolation. Reasonable curing process parameters were determined by analyzing the predicted curing degree curves. Then, CFRTPC samples were prepared with the low‐temperature 3D printing process and the low‐temperature curing process, and the fiber content was found to be 53 wt.%. At last, the mechanical property measurements revealed that the tensile and flexural strengths were 1012 MPa and 929 MPa, respectively. This work can further expand the potential applications of 3D printed CFRTPCs in aerospace and defense industries which require high mechanical properties and temperature safety simultaneously. [ABSTRACT FROM AUTHOR]

The applications of alloy‐type anode materials for Na‐ion batteries are always obstructed by enormous volume variation upon cycles. Here, K+ ions are introduced as an electrolyte additive to improve the electrochemical performance via electrostatic shielding, using Sn microparticles (μ‐Sn) as a model. Theoretical calculations and experimental results indicate that K+ ions are not incorporated in the electrode, but accumulate on some sites. This accumulation slows down the local sodiation at the "hot spots", promotes the uniform sodiation and enhances the electrode stability. Therefore, the electrode maintains a high specific capacity of 565 mAh g−1 after 3000 cycles at 2 A g−1, much better than the case without K+. The electrode also remains an areal capacity of ≈3.5 mAh cm−2 after 100 cycles. This method does not involve time‐consuming preparation, sophisticated instruments and expensive reagents, exhibiting the promising potential for other anode materials. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries show promising potential for large‐scale energy storage. However, the large size and heavy mass of Na+ always results in huge volume change and inferior electrochemical stability, especially in alloy‐type anode materials. Here, molecular engineering of the polymer binders, i.e., cross‐linking of poly(acrylic acid) with glycerin (PAA‐GLY), reinforces the mechanical properties, eliminates the active protons of PAA, and benefits electrolyte diffusion, thereby remarkably improving electrochemical performance. Using µ‐Sn as an example, the cycle life at 2 A g−1 is extended from ≈26 cycles of PAA to ≈2000 cycles of PAA‐GLY. Meanwhile, the initial Coulombic efficiency is promoted to 90.3%, allowing the fabrication step of electrode presodiation for full cells to be eliminated. Thus, the full cells run 300 cycles at 2 A g−1. In addition, the binder allows the thick electrode to exhibit an areal capacity of 6.8 mAh cm−2. This binder is also applied for µ‐Bi and µ‐Sb. The simple operation, remarkable improvement, and wide applications indicate the promising prospects of this strategy for advanced electrodes in sodium ion batteries. [ABSTRACT FROM AUTHOR]

Li‐ion batteries with LiFePO4 cathode and Li4Ti5O12 anode show promise for storing renewable energy. However, their low output voltage results in a low energy density. In contrast, dual‐ion batteries with graphite cathode and Li4Ti5O12 anode can achieve a high output voltage of >3.0 V. In this study, mesocarbon microbeads (MCMB)@LiFePO4||Li4Ti5O12 dual‐ion batteries are developed to address these issues. In the cathode, MCMB improves the conductivity of LiFePO4 and increases the output voltage by the intercalation of anions in the cell voltage range of 2.1–3.5 V. Moreover, the LiFePO4 shell sustains the structural integrity of MCMB and generates in situ a cathode‐electrolyte interphase (CEI) with rich LiF. Owing to these unique compositional and structural features, MCMB@LiFePO4||Li4Ti5O12 manifests much better electrochemical performance than LiFePO4||Li4Ti5O12 and MCMB||Li4Ti5O12. It sustains 89.6 % of the initial capacity after 1200 cycles at 0.2 A g−1 and achieves a specific energy up to 128 Wh kg−1 at 179 W kg−1. [ABSTRACT FROM AUTHOR]

Abstract: No metal needed: A core‐shell‐like carbon catalyst consisting of a few layers of nitrogen‐doped graphite on a carbon black core was prepared by pyrolyzing an ionic liquid (IL) with carbon black (CB) particles. The catalyst has a noticeably improved OER performance of the nanocarbon in acid solution. The resilience of the catalyst in acid solution is due to the greater protection of the nitrogen‐containing OER active sites in a graphitic shell. The oxygen evolution reaction (OER) in acid solution is very challenging for metal‐free catalysts based only on heteroatom‐doped carbon nanomaterials which have thus far shown relatively low catalytic activity and poor stability. Herein, we report a core‐shell‐like carbon catalyst consisting of a few layers of nitrogen‐doped graphite on a carbon black core prepared by pyrolyzing an ionic liquid (IL) with carbon black (CB) particles. The catalyst prepared as such has a noticeably improved OER performance of the nanocarbon in acid solution (1.70 V at a current density of 10 mA cm−2) in comparison with the few metal‐free OER electrocatalysts reported to date. The experimental results suggest that the resilience of the catalyst in acid solution is due to the greater protection of the nitrogen‐containing OER active sites in a graphitic shell. [ABSTRACT FROM AUTHOR]

In alkaline medium, it seems that both metal-free and iron-containing carbon-based catalysts, such as nitrogen-doped nanocarbon materials, FeO x-doped carbon, and Fe/N/C catalysts, are active for the oxygen reduction reaction (ORR). However, the order of activity of these different active compositions has not been clearly determined. Herein, we synthesized nitrogen-doped carbon black (NCB), Fe3O4/CB, Fe3O4/NCB, and FeN4/CB. Through the systematic study of the ORR catalytic activity of these four catalysts in alkaline solution, we confirmed the difference in the catalytic activity and catalytic mechanism for nitrogen, iron oxides, and Fe-N complexes, respectively. In metal-free NCB, nitrogen can improve the ORR catalytic activity with a four-electron pathway. Fe3O4/CB catalyst did not exhibit improved activity over that of NCB owing to the poor conductivity and spinel structure of Fe3O4. However, FeN4 coordination compounds as the active sites showed excellent ORR catalytic activity. [ABSTRACT FROM AUTHOR]

Nitrogen-doped nanocarbon materials as metal-free electrocatalysts for the oxygen reduction reaction (ORR) have attracted great attention, owing to their catalytic activity close to Pt/C in alkaline media. Annealed nanodiamonds (AND) possess a special structure, because we can finely control the carbon sp2/sp3 ratio. This provides a good opportunity to study the relationship between ORR performance (activity and stability) and the special structure of AND. We have used nitrogen-doped annealed nanodiamonds (NAND) with varied carbon sp2/sp3 ratio as metal-free electrocatalysts for ORR in alkaline media. NAND showed higher catalytic activity for ORR with higher content of sp2 carbon and larger amount of nitrogen species present as pyridinic groups. More importantly, NAND displayed stability superior to other nitrogen-doped nanocarbon materials as a result of transformation of carbon from sp3 to sp2 during electrochemical cycling. [ABSTRACT FROM AUTHOR]

Non-precious Fe/N co-modified carbon electrocatalysts have attracted great attention due to their high activity and stability in oxygen reduction reaction (ORR). Compared to iron-free N-doped carbon electrocatalysts, Fe/N-modified electrocatalysts show four-electron selectivity with better activity in acid electrolytes. This is believed relevant to the unique Fe-N complexes, however, the Fe-N structure remains unknown. We used o,m,p-phenylenediamine as nitrogen precursors to tailor the Fe-N structures in heterogeneous electrocatalysts which contain FeS and Fe3C phases. The electrocatalysts have been operated for 5000 cycles with a small 39 mV shift in half-wave potential. By combining advanced electron microscopy and Mössbauer spectroscopy, we have identified the electrocatalytically active Fe-N6 complexes (FeN6, [FeIII(porphyrin)(pyridine)2]). We expect the understanding of the FeN6 structure will pave the way towards new advanced Fe-N based electrocatalysts. [ABSTRACT FROM AUTHOR]