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Cordierite is a violet-blue gem mineral primarily composed of magnesium aluminum silicate. This study employed three samples of Mg-cordierite and conducted tests on their gemological characteristics, spectroscopic features, and chemical composition using Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, ultraviolet spectrophotometry, X-ray photoelectron spectroscopy (XPS), and electron microprobe. The study also explored and analyzed the polychroism and coloration mechanisms of the samples. The results indicate that the lattice vibrations of the Mg-cordierite samples differ along the directions parallel to the a, b, and c crystallographic axes, leading to certain variations in spectral characteristics among these directions. The article provides experimental evidence for the reasons for the polychroism of cordierite in different crystal axes, which is of great significance in the quality evaluation of cordierite. [ABSTRACT FROM AUTHOR]

The distance effect of the doped heteroatoms away from the catalytic centers has rarely been reported. In this work, we conducted density functional theory calculations to thoroughly investigate the influence of heteroatom (N, P, B, and S atoms) doping distance on the oxygen reduction reaction (ORR) activity of graphene-based FeN4 sites. We uncovered a Sabatier-like relationship between heteroatom doping distance and ORR activity of FeN4 sites. The nearest doping does not significantly improve and even block the ORR activity of FeN4 sites. Optimal ORR activity is achieved when the heteroatoms are 4–5 Å (N, P, and S atoms) or 6–7 Å (B atoms) away from the Fe atoms. Analysis of electronic structure indicates that distance effect can modulate the local chemical environment of Fe atoms, thereby account for the changes in ORR activity along with the doping distance and doping atoms. This study provides insights into the influence of heteroatom doping on the chemical environment of reaction active centers, and provides the theoretical guidance for controlling the doping distance of heteroatoms to achieve optimal catalytic activity and selectivity. [ABSTRACT FROM AUTHOR]

Genomic imprinting refers to allele-specific expression of genes depending on parental origin, and it is regulated by epigenetic modifications. Intraspecific allelic variation for imprinting has been detected; however, the intraspecific genome-wide allelic epigenetic variation in maize and its correlation with imprinting variants remain unclear. Here, three reciprocal hybrids were generated by crossing Zea mays inbred lines CAU5, B73, and Mo17 in order to examine the intraspecific conservation of the imprinted genes in the kernel. The majority of imprinted genes exhibited intraspecific conservation, and these genes also exhibited interspecific conservation (rice, sorghum, and Arabidopsis) and were enriched in some specific pathways. By comparing intraspecific allelic DNA methylation in the endosperm, we found that nearly 15% of DNA methylation existed as allelic variants. The intraspecific whole-genome correlation between DNA methylation and imprinted genes indicated that DNA methylation variants play an important role in imprinting variants. Disruption of two conserved imprinted genes using CRISPR/Cas9 editing resulted in a smaller kernel phenotype. Our results shed light on the intraspecific correlation of DNA methylation variants and variation for imprinting in maize, and show that imprinted genes play an important role in kernel development. [ABSTRACT FROM AUTHOR]

Traditional luminescent materials commonly exhibit single‐duration emissions and single‐timed emissions with limited emission peaks. Developing a material with multicolor, variable temporal, and multimodal luminescence is a significant challenge. Self‐reduction phosphors have attracted considerable interest for their distinctive properties and versatile applications. Distinguished by their rigid structure and exceptional purity, offer a safer alternative to conventional reduction methods using hazardous gases H2/CO/N2. However, synthesizing these phosphors with precise control over self‐reduction and defect regulation is complex. Therefore, innovative structures and substrates are essential to address these challenges. This review discusses the latest developments in phosphors doped with ions such as Eu3+, Mn4+, Ce4+, and Yb3+, examining the origins and advancements in self‐reduction. It covers classifications, mechanisms, defects, and applications, with an emphasis on techniques for controlled self‐reduction through structural and charge transfer modifications. This work aims to provide valuable insights to facilitate further research and innovation endeavors. [ABSTRACT FROM AUTHOR]

The advancement of metal-air batteries is critically contingent on the progression of efficient catalysts for the oxygen reduction reaction (ORR). The potential applications of a series of FeN 4 -doped carbon nanotubes (Fe-N 4 CNTs) of varying diameters as ORR catalysts were examined using density functional theory. We explored the stability and electronic properties of Fe-N 4 CNTs by analyzing the energy and examining the density of states. A marked dependence of the catalytic performance on the nanotube diameter was observed: as the transition from (5, 5) to (10, 10) Fe-N 4 CNTs occurred, the catalytic activity on the outer surface of the carbon tubes enhanced progressively, with the overpotential reducing from 0.94 to 0.86 V. Conversely, the catalytic activity on the inner surface of the carbon tubes decreased progressively with the overpotential also increasing from 0.62 to 1.04 V. In addition, we found that curvature significantly affected the electronic structure and charge transfer at the FeN 4 site, regulating the adsorption and desorption of reactants, intermediates, and products during electrocatalysis and thus influencing the catalytic activity of the Fe-N 4 CNTs. This investigation offers valuable guidance for the design of Fe-based single-atom catalysts and the practical application of Fe-N-C materials.

Edible fungus polysaccharides have garnered significant attention from scholars due to their safety and potential anti-inflammatory activity. However, comprehensive summaries of their anti-inflammatory properties are still rare. This paper provides a detailed overview of the anti-inflammatory effects and mechanisms of these polysaccharides, as well as their impact on inflammation-related diseases. Additionally, the relationship between their structure and anti-inflammatory activity is discussed. It is believed that this review will greatly enhance the understanding of the application of edible fungus polysaccharides in anti-inflammatory treatments, thereby significantly promoting the development and utilization of edible fungi., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Yin, Zhang, Qin, Guo, Guo, Kang, Ma and Chen.)

The doping of semiconductor materials through some facile and appropriate methods holds significant promise in enhancing the catalytic performance of catalysts. Herein, NiCo 2 O 4 /g-C 3 N 4 composite catalysts were synthesized via a high-energy ball milling method. The microstructure and physicochemical characterization of the as-prepared composites confirmed the successful loading of NiCo 2 O 4 nanoparticles onto the g-C 3 N 4 nanosheets. The NiCo 2 O 4 /g-C 3 N 4 composites showed excellent catalytic effect under visible light/ultrasonic irradiation, and the efficiency of tetracycline hydrochloride (TCH) degradation reached 90% within 15 min. The optical properties of g-C 3 N 4 nanosheets were improved by doping, and the diffusion of active materials and carrier migration rate were improved by ultrasonic assistance. Possible catalytic mechanisms and potential pathways of the NiCo 2 O 4 /g-C 3 N 4 composites for the degradation of TCH triggered by visible light/ultrasonic irradiation were proposed. This study provides a new strategy for energy-assisted photocatalytic degradation of organic pollutants.