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Changes in vitamin C, vitamin E, and carotenoid metabolism during early kernel development in maize

Nan Xiang,Xinbo Guo

BACKGROUND Maize ( Zea mays L.), as the most widely cultivated cereal and a dietary cornerstone, provides not only carbohydrates but also essential micronutrients critical for human health, including vitamin C, vitamin E, and carotenoids. However, conventional maize varieties typically exhibit suboptimal levels of these compounds. This study investigated the dynamic accumulation of vitamin C, vitamin E, and carotenoids, along with their transcriptional regulation, during early kernel development (9–15 days after pollination (DAP)) in maize. RESULTS Combined metabolite and transcriptome analyses showed a 23-fold increase in vitamin C content, associated with enhanced expression of the gene VTC2 . Id1 and AGAMOUS-like MADS-box transcription factors (TFs) are putative regulators, targeting the promoters of GalDH and VTC2 to regulate vitamin C biosynthesis. Vitamin E showed isomer-specific fluctuations during early kernel development, mainly associated with the expression of VTE1 , VTE2 , and VTE4 , and potentially regulated by knotted 1 and the AGAMOUS-like MADS-box TFs via VTE2 and VTE3 , respectively. Total carotenoid content tripled, with zeaxanthin becoming dominant by 15 DAP, driven by upregulated PSY1 and CHYB-1 . ERF003 was identified as a candidate regulator of PSY3 . CONCLUSION The increases in vitamin C and carotenoid content, and the fluctuation of vitamin E isomers during early maize kernel development, were associated with the modulation of key genes and putative TFs. These findings reveal theoretical insights and provide candidate genetic targets for future breeding efforts aimed at enhancing micronutrient levels in maize. © 2026 Society of Chemical Industry.

Multilayer Carbon-Structured BaTiO3@C Nanocomposites with Wide Microwave Absorption Bandwidth and Excellent Corrosion Resistance

Sichen Guo,Yijing Sun,Shanxin Li,Xuzhou Jiang,Dongbai Sun

Developing lightweight materials that simultaneously achieve efficient electromagnetic wave absorption and robust corrosion resistance remains a significant challenge for marine stealth and electromagnetic protection applications. The main obstacle lies in the rational integration of electromagnetic attenuation capability, impedance matching, and corrosion protection. In this work, a multilayer carbon-structured BaTiO3@C nanocomposite (CSTB-x) was successfully fabricated via freeze-drying combined with in situ pyrolysis. During the carbonization process, chitosan (CS) was transformed into a nitrogen-doped multilayer porous carbon framework, while BaTiO3particles were embedded into the carbon matrix to construct a BaTiO3@C heterostructure. Benefiting from optimized impedance matching and the synergistic contributions of conduction loss, dipolar polarization, and interfacial polarization, CSTB-1.0 delivered a minimum reflection loss (RLmin) of −48.07 dB at 6.16 GHz with a thickness of 3.32 mm, and achieved a maximum effective absorption bandwidth (EAB) of 7.04 GHz at a thickness of 1.88 mm. In addition, CSTB-1.0 exhibited a low corrosion current density (8.93 × 10−6A/cm2) and a high polarization resistance (7.87 × 103Ω∙cm2), indicating excellent corrosion protection performance. The enhanced corrosion resistance is mainly attributed to the barrier effect of the multilayer carbon framework and the tortuous diffusion pathways generated by the porous and core–shell structures. Moreover, the material showed a minimum radar cross-section (RCS) value of −41.25 dBsm, demonstrating remarkable electromagnetic scattering suppression capability. These results provide a feasible strategy for the design and fabrication of marine stealth materials with integrated microwave absorption and corrosion resistance.

In Situ Generated Mullite Reinforced Flexible Zirconia Nanofibers With Exceptional Thermostability up to 1400°C

Shuang Wang,Xinling Wang,Zhipeng Yang,Qingyang Tan,Bingwen Liu,Xinran Zhou,Yuhang Jiang,Kangkang Yuan,Xiaotong Jin

Zirconia (ZrO 2 ) nanofibers have emerged as ideal flexible materials for thermal-field applications in semiconductor crystal growth furnaces, thermal protection of new energy batteries, and flexible thermal insulation layers of aerospace vehicles, attributed to their unique combination of low saturated vapor pressure, ultralow thermal conductivity, and ultrahigh melting point. However, rapid grain coarsening at elevated temperatures restricts their long-term service temperature, severely hindering their practical deployment in these critical fields. To address this bottleneck, we proposed a novel strategy: sacrificing the theoretical ultrahigh-temperature stability (> 1600°C) of ZrO 2 nanofibers by in situ generating mullite phases—characterized by relatively low melting points, complex crystal structures, and slow grain growth rates—thereby achieving mullite-reinforced ZrO 2 nanofibers with exceptional comprehensive high-temperature performance. Systematic characterizations demonstrated that the introduction of mullite enhanced the flexible service temperature of ZrO 2 nanofibers from 1200°C to 1300°C, while extending the high-temperature thermal stability to 1400°C, alongside sustained low room-temperature thermal conductivity and reliable performance under extreme environments. Mechanistic investigations revealed that the in situ formed mullite inhibited particle growth in ZrO 2 nanofibers, thus improving the high-temperature flexibility and stability. Notably, our findings indicate that the particle size on the fiber surface—rather than the grain size—serves as the key determinant of high-temperature stability and flexibility, providing a new microstructure-oriented approach for the optimization and development of advanced oxide fibers. This work not only enhances the comprehensive high-temperature performance of ZrO 2 nanofibers and expands their ultrahigh-temperature application scenarios but also offers a novel strategy for the optimization and development of other inorganic fibers.

Heterogeneous Interface Engineering Enabled ZnO/C Hybrid Aerogels for High-Performance Radar-Infrared Compatible Stealth

Gu Weihua,Tan Xin,Liu Tao,Tao Zhe,Liu Juan,Du Wenbo,Xia Ailin

Pure carbon aerogels are constrained by insufficient electromagnetic loss mechanisms and poor compatibility between radar wave absorption and infrared stealth. Here, a heterogeneous interface engineering strategy is developed to construct ZnO/C hybrid aerogels derived from ZIF-8 and chitosan, featuring ZnO/C interfacial structures and hierarchical meso/macroporous structures. The hybrid aerogel sample, carbonized at 800 ° C (CA-Z-800), achieves optimal microwave absorption performance with a minimum reflection loss (RL min ) of –35.74 dB and an effective absorption bandwidth (EAB) of 4.55 GHz at a matching thickness of only 1.5 mm. Simultaneously, it maintains effective infrared stealth performance with a low thermal conductivity of 0.151 W/(m·K), a surface temperature rise of only ∼4 ° C, and infrared emissivity of 0.654 (3–5 μm) and 0.638 (8–14 μm). Notably, although increasing carbonization temperature to 900 ° C further reduces emissivity to 0.601 and 0.595, it severely degrades impedance matching, leading to a much weaker reflection loss (–13.53 dB) and a narrower effective bandwidth (2.85 GHz). This trade-off reveals that CA-Z-800 represents the optimal balance for radar-infrared compatible stealth. Density functional theory (DFT) calculations elucidate charge redistribution and enhanced interfacial polarization at the ZnO/C interfacial structures, while computer simulation technology (CST) simulations confirm strong microwave attenuation. Systematic control of pyrolysis temperature and ZnO microstructure enables tuning of dielectric properties and thermal insulation. These findings demonstrate a correlation between radar absorption and infrared suppression, with CA-Z-800 achieving the optimal balance among the samples tested.

Non-Noble Metal Ni/NiOx@C Co-Catalyst Modified ZnIn2S4 for Efficient Photocatalytic Hydrogen Production

Photocatalytic hydrogen production has emerged as one of the most promising approaches for addressing the global energy crisis by enabling the sustainable conversion of solar energy into clean hydrogen fuel. However, its practical application is still hindered by the rapid recombination of photogenerated electron–hole pairs, which severely limits photocatalytic efficiency. Although noble-metal co-catalysts have been demonstrated to markedly promote charge separation and accelerate surface reaction kinetics, their widespread application remains constrained by their high cost and limited availability. In this study, a non-noble Ni/NiOx@C co-catalyst was fabricated and employed to modify ZnIn2S4(ZIS) for photocatalytic hydrogen production. The optimized sample (15Ni/NiOx@C/ZIS) exhibits a hydrogen production rate of 4140.03 μmol/g/h, 18.16 times higher than that of pristine ZIS. This enhancement is primarily attributed to the improved separation and transfer of photogenerated charge carriers facilitated by the Ni/NiOx@C co-catalyst. Notably, the hydrogen evolution rate of 15Ni/NiOx@C/ZIS is 1.33 times higher than that of ZIS/3%Pt, suggesting that Ni/NiOx@C has great potential as a substitute for noble metal Pt. Various characterization results demonstrate that 15Ni/NiOx@C/ZIS exhibits superior photocatalytic performance, ascribed to its enhanced light absorption capability, and efficient separation of photogenerated carriers. Additionally, cycling tests and XRD analysis confirm the excellent stability of 15Ni/NiOx@C/ZIS, indicating its potential for practical applications. This work provides a valuable reference for the rational design and development of efficient and cost-effective non-noble co-catalysts for photocatalytic hydrogen production.

Synergistic Ti-Ni co-doping enhances the electrochemical performance and densification of LiMn0.6Fe0.4PO4/C cathodes

Long Ye,Juntao Si,Cheng Zhang,Sihan Zeng,Chunhua Chen

Ti-Ni co-doping improves electrochemical kinetics and powder densification. • Dopants Ti and Ni function on the Mn- and Fe-redox regions, respectively. • Powder compaction density increases by 8.5% to 2.04 g cm −3 after Ti-Ni doping. LiMn 0.6 Fe 0.4 PO 4 (LMFP) is a promising high-energy cathode, but its practical application is constrained by sluggish Mn 2+ /Mn 3+ redox kinetics and insufficient powder compaction density (PCD). Herein, Ti-doped, Ni-doped, and Ti–Ni co-doped LMFP/C were prepared by a ball-milling-assisted solid-state route. It is clarified that Ni predominantly accelerates the Fe 2+ /Fe 3+ reaction, whereas Ti promotes the kinetically slower Mn 2+ /Mn 3+ reaction and improves cycling stability. The optimal sample LMFP-2Ti-2Ni delivers 163.1 and 142.9 mAh g −1 at 0.1 and 5 C, respectively, and retains 90.8% of its capacity after 400 cycles at 1 C. Relative to pristine LMFP, the Ti-Ni co-doping increases the 0.1 C capacity from 144.7 to 163.1 mAh g −1 (+12.7%) and the PCD from 1.88 to 2.04 g cm −3 (+8.5%). Also, the relative unit-cell-volume variation decreases from approximately 5.2% to 4.6%, indicating more gradual bulk-lattice evolution. Thus, Ti–Ni co-doping as a complementary strategy can simultaneously improve rate capability, cycling durability, and particle packing in LMFP/C cathodes. Download: Download high-res image (356KB) Download: Download full-size image

Rapid selective analysis of arsenic and antimony using a novel Au-Fe3O4-C electrode sensor

Yaqin Yu,MengXue Wei,Junting Tong,Zhengdong Zhang,Xiaowei Song,Anni Liu,Rui Wang,Yu Zhang,Zhen Zhou

Arsenic (As) and antimony (Sb) are emerging pollutants with significant toxicity and carcinogenic potential. Their contamination in drinking water represents a health and safety risk. A novel Au-Fe 3 O 4 -C sensor was synthesized using an electrodeposition technique that leverages the superior electro-catalytic properties of gold (Au), the high adsorption capacity of Fe 3 O 4 , and the excellent conductivity of carbon fiber cloth. The Au-Fe 3 O 4 -C sensor enhanced the sensitivity of As and Sb stripping signals and reduced the limits of detection. Square wave voltammetry (SWV), used for As analysis, yielding LODs of 0.24 μg L −1 for As(III) and 1.20 μg L −1 for As(V). Differential pulse voltammetry (DPV), used for Sb analysis, yielding LODs of 0.50 μg L −1 for Sb(III) and 0.60 μg L −1 for Sb(V). We report quantitative detection of As and Sb in a mixed solution through DPV combined with the non-linear least squares based on Pearson function. The portable electrochemical workstation combined with Au-Fe 3 O 4 -C sensor was installed on a mobile inspection vehicle to detect As/Sb in groundwater (Shanxi, China) and rivers (Hunan, China). The indication error reached below12%, confirming the capability of electrochemistry based on Au-Fe 3 O 4 -C sensor for the field determination.

Decarbonylation of Fatty Acids to Alkenes over Co-N-C Catalysts Derived from Co Complexes

Canyang Zhang,Yin Liang,Chao Chen,Wei Zhao,Bolong Li,Jianghao Wang,Zhenyu Zhang,Huiping Ji,Feng Zhou,Kaige Wang,Reinout Meijboom,Jie Fu

The decarbonylation of biomass-derived fatty acids (CnH2n+1COOH) presents a sustainable method for producing high-value alkenes (CnH2n). However, the development of efficient and highly selective catalysts for fatty acid decarbonylation remains challenging. In this work, we prepared a series of CoPhPhen/MWCNT-X catalysts by pyrolyzing a 4,7-diphenyl-1,10-phenanthroline (PhPhen) Co complex immobilized on multi-walled carbon nanotubes. In the model decarbonylation reaction of stearic acid, the optimized CoPhPhen/MWCNT-900 catalyst demonstrated remarkable catalytic efficacy, with 81.6% conversion of stearic acid and 58.3% yield of heptadecene. Characterization and comparative experiments demonstrated that the substantial phenyl groups in the PhPhen ligand engage in strong π-π interactions with the MWCNT, effectively inhibiting the migration and aggregation of cobalt single atoms during pyrolysis and thus maintaining a high density of active Co single-atom sites. Further electronic structure investigation revealed that the local electron density around the cobalt species markedly rises with higher pyrolysis temperatures, and this electronic impact exhibits a distinct positive association with the decarbonylation performance of catalysts. In situ DRIFTS was employed to reveal the adsorption and reaction process of fatty acids on the Co single-atom active sites: The fatty acid molecule first coordinates to the cobalt center via the carbonyl oxygen, followed by successive dehydration and decarbonylation processes, finally yielding H2O, CO, and olefins.

Synthesis of PdV/C nanoparticles using phase transfer method for oxygen reduction in alkaline electrolytes

Biyao Jin,Yiqi Li,Lianhua Zhao

Bimetallic PdV/C nanoparticles have been synthesized by phase-transfer method for catalyzing the oxygen reduction reaction (ORR) in alkaline electrolytes . PdV/C nanoparticles with different V contents are spherical with a mean diameter of 3–4 nm, and the addition of V expands the lattice parameter of Pd as shown by XRD . XPS analysis indicated the binding energy of Pd 0 3d peak increased by ca. 1 eV. Density functional theory (DFT) calculations results shows d-band center of Pd down-shift after V-doping. Based on the electrocatalytic results, introducing V can improve the catalytic activity for ORR, methanol crossover tolerance and stability. Especially, Pd 4 V/C shows higher initial potential (E onset  = 1.027 V), excellent methanol crossover tolerance (98.03% retained) and long-term stability (81.30% retained), which are comparable with Pt/C JM . This work provides a new method of synthesizing PdV/C nanoparticles , which have the potential to be used as the cathode electrocatalysts for fuel cells.

High durability of Pt-Ni-Ir/C ternary catalyst of PEMFC by stepwise reduction synthesis

Rui Lin,Lu Che,Dandan Shen,Xin Cai

How to improve durability of catalysts is the major challenge hindering the large-scale implementation of proton exchange membrane fuel cells (PEMFCs). The alloy catalysts have been developed in efforts to reduce platinum loading, enhance catalysts activity and durability for oxygen reduction reaction (ORR) of PEMFCs. This manuscript reports the application of stepwise reduction synthesis to synthesize Pt–Ni/C and Pt–Ni–Ir/C catalysts. The synthesized electrocatalysts were characterized by X–ray diffraction (XRD), transmission electron microscopy (TEM), inductively coupled plasma mass spectrometry (ICP), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV) and linear sweep voltammetry (LSV). The results from CV and LSV showed that when as-prepared Pt–Ni–Ir nanocrystals are uniformly dispersed on the carbon support, the catalyst exhibits excellent electrocatalytic activity and stability. When the atomic ratio of Pt, Ni, Ir is 2:2:1, after durability test of 5000 cycles, rotating disk electrode (RDE) demonstrated ORR activities of the as-prepared catalysts with the highest mass activity (MA) of 351 m A ⋅ g P t − 1  at 0.9V iR-free and electrochemically active surface area (ECSA) of 80 m 2 ⋅ g P t − 1 , which is over 17 and 2 times than those of Pt/C JM (Johnson Matthey) catalyst, respectively. This work highlights the potential to use a preparative method which means step-by-step reduction synthesis to form ternary alloy catalysts for ORR of PEMFCs.

Rationally designed C-PANI/BiOBr STEP-scheme heterojunction photocatalyst for boosting photodegradation of 17β-estradiol

Yashi Qing,Yanxiang Li,Lixia Cao,Yujie Yang,Li Han,Panchan Dansawad,Haigang Gao,Wangliang Li

17β-estradiol (E2) in natural water has caused serious environmental problems because of its extremely high estrogenic activity. Herein, a novel β-CD@PANI/BiOBr (C-PANI/BiOBr) step scheme (S-scheme) heterojunction photocatalyst was successfully prepared via facile chemical precipitation method. The encapsulation of β-cyclodextrin (β-CD) around polyaniline (PANI) contributed to better transfer of photogenerated carries by the stabilization of radical cation and excellent adsorption capability driven by hydrophobic interaction, hydrogen bonding and π-π stacking. The C-PANI/BiOBr heterojunction photocatalysts realized excellent light absorption in full spectrum. The N derived from C-PANI could coordinate with Bi metal ions, which favored forming BiOBr with (1   1   0) facet exposure, thus promoting the photogenerated electron-hole separation. The optimal 20% C-PANI/BiOBr achieved rapid degradation of contaminants (100% removal of E2 in 40 min and RhB in 9 min) under visible light irradiation. Furthermore, three main degradation pathways of E2 photodegradation were proposed by high performance liquid chromatography-mass spectrometer (HPLC-MS) results, and the toxicity of E2 and intermediates were evaluated by ECOSAR program. The active species capture experiment indicated that h + and •O 2 – played the dominated roles in the photodegradation process and S-scheme mechanism of C-PANI/BiOBr with enhanced photocatalytic performance was also revealed. This study provided an insight in fabricating efficient photocatalysts for environmental remediation.

Pd/C catalytic cyclopropanation of polycyclic olefins for synthesis of high-energy-density strained fuels

Wei Wang,Baian Pu,Chi Ma,Chengxiang Shi,Lun Pan,Xiangwen Zhang,Ji-Jun Zou

Cyclopropane derivates are appealing to synthesis of high-energy-density fuels because of the high strained energy of the three-numbered ring. The catalytic cyclopropanation of olefin with diazomethane is very effective to construct the carbocycle. The majority of the catalysts employed are nonrecyclable homogeneous compounds. Herein, we report cyclopropanation of polycyclic olefins catalyzed by heterogeneous Pd/C. The optimal cyclopropanation conditions were explored utilizing dicyclopentadiene as model substrate and a series of polycyclic olefins were cyclopropanated with high yield. Additionally, the catalyst has good recyclability and stability, as shown by characterizations as well as the fact that no inactivation happens after cyclopropanation. The synthesized cyclopropane derivates exhibit good fuel characteristics like high density (1.006–1.087 g/cm 3 ), high volumetric net heat of combustion (42.58–46.45 kJ/cm 3 ), good low-temperature and combustion performance. This work shows industrial potential for cyclopropanation of polycyclic olefins with diazomethane.