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Selective hydrocracking of polycyclic aromatic hydrocarbons (PAHs) from heavy oils and tar to high‐value chemicals such as benzene, toluene, and xylene (BTX) is a promising technology. Due to the lack of comprehensive and rational understanding of the reaction mechanisms, the development and preparation of catalysts and the improvement of catalysis technology are rarely carried out. Since zeolites as crucial solid acid catalyst components in catalytic hydrocracking of PAHs are indispensable, this review systematically analyzed the mechanisms and research advances in hydrogenation, isomerization, and ring‐opening (cracking) on zeolite catalysts. Efficient zeolite catalysts for hydrocracking should have appropriate pore structures for the required diffusivity for reactants and products to avoid secondary polymerization and coke formation, an ideal distribution and strength of acid sites for the formation of the desired carbocation intermediates to achieve the selectivity of products and precisely tunable metal to acid functions to control the competition between (de)hydrogenation and ring‐opening reactions leading to the facilitation of the reaction mechanisms for the desired products. This poses challenges for the research and development of industrial relevant zeolite catalysts. [ABSTRACT FROM AUTHOR]

Nowadays, sodium‐ion batteries are considered the most promising large‐scale energy storage systems (EESs) due to the low cost and wide distribution of sodium sources as well as the similar working principle to lithium‐ion batteries (LIBs). Therefore, screening suitable materials with high abundance, low cost, and excellent reliability and modified with different strategies based on them is the key point for the development of sodium‐ion batteries (SIBs). In addition, the ideal anodes with high abundance, and low cost elements also greatly influence the cost of SIB systems, determining the large‐scale application. Herein, recent advances in carbon, iron, manganese, and phosphorus‐based anodes of various types, such as hard carbon, iron oxides, manganese oxides, and red phosphorus, are highlighted. The various sodium storage mechanisms and structure‐function properties for these four types of materials are summarized and analyzed in detail. Considering the commercial profits that the EESs can bring and their suitability for mass electrode manufacturing, the participation of high‐abundance and low‐cost elements such as Fe, Mn, C, and P is convincing and encouraging. [ABSTRACT FROM AUTHOR]

Waste plastics bring about increasingly serious environmental challenges, which can be partly addressed by their interconversion into valuable compounds. It is hypothesized that the porosity and acidity of a zeolite‐based catalyst will affect the selectivity and effectiveness, enabling a controllable and selective conversion of polyethylene (PE) into gas‐diesel or lubricating base oil. A series of embryonic, partial‐ and well‐crystalline zeolites beta with adjustable porosity and acidity are prepared from mesoporous SBA‐15. The catalysts and catalytic systems are studied with nuclear magnetic resonance (NMR), X‐ray diffraction (XRD), and adsorption kinetics and catalytic reactions. The adjustable porosity and acidity of zeolite‐beta‐based catalysts achieve a controllable selectivity toward gas‐diesel or lubricating base oil for PE cracking. With a catalyst with mesopores and appropriate acid sites, a fast escape and reduced production of cracking of intermediates are observed, leading to a significant fraction (88.7%) of lubricating base oil. With more micropores, a high acid density, and strong acid strength, PE is multiply cracked into low carbon number hydrocarbons. The strong acid center of the zeolite is confirmed to facilitate significantly the activation of hydrogen (H2), and, an in situ ammonia poisoning strategy can significantly inhibit hydrogen transfer and effectively regulate the product distribution. [ABSTRACT FROM AUTHOR]

(1) Soil alkalinization and salinization represent a growing global challenge. Maize (Zea mays L.), with its relatively low tolerance to salt and alkali, is increasingly vulnerable to saline‐alkali stress. Identifying maize genotypes that can withstand salinity and alkalinity is crucial to broaden the base of salt‐alkali‐tolerant maize germplasm. (2) In this study, we screened 65 maize germplasm resources for alkali stress using a 60 mM NaHCO3 solution. We measured fifteen morphological and physiological indices, including seedling height, stem thickness, and leaf area. Various analytical methods—correlation analysis, principal component analysis, subordinate function analysis, cluster analysis, stepwise discriminant analysis, and ridge regression analysis—were used to assess the seedling alkali tolerance of these maize germplasm resources. The physiological indices of six tested maize varieties were analyzed in greater detail. (3) The findings revealed complex correlations among traits, particularly strong negative associations between conductivity and root traits such as length, volume, surface area, diameter, and number of branches. The 15 evaluation indices were reduced to 7 principal components, explaining 77.89% of the variance. By applying affiliation functions and weights, we derived a comprehensive evaluation of maize seedling alkali tolerance. Notably, three germplasms—Liang Yu 99, Bi Xiang 638, and Gan Xin 2818—demonstrated significant comprehensive seedling alkali tolerance. Cluster analysis grouped the 65 maize germplasm resources into four distinct categories (I, II, III, and IV). The results of the cluster analysis were confirmed by multiclass stepwise discriminant analysis, which achieved a correct classification rate of 92.3% for 60 maize genotypes regarding alkalinity tolerance. Using principal component and ridge regression analyses, we formulated a regression equation for alkali tolerance: D‐value = −1.369 + 0.002 * relative root volume + 0.003 * relative number of root forks + 0.006 * relative chlorophyll SPAD + 0.005 * relative stem thickness + 0.005 * relative plant height + 0.001 * relative conductivity + 0.002 * relative dry weight of underground parts. Under sodium bicarbonate stress, morphological indices and germination rates were significantly reduced, germination was inhibited, photosynthetic pigment levels in maize leaves decreased to varying degrees, and the activities of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) significantly increased. Alkali stress markedly enhanced the antioxidant enzyme activities in maize varieties, with alkali‐resistant varieties exhibiting a greater increase in antioxidant enzyme activities than alkali‐sensitive varieties under such stress. (4) By screening for alkali tolerance in maize seedlings, the identified alkali‐tolerant genotypes can be further utilized as suitable donor parents, thereby enhancing the use of alkali‐tolerant germplasm resources and providing theoretical guidance for maize cultivation in saline‐alkaline environments. [ABSTRACT FROM AUTHOR]

Compared to conventional quantum dot light-emitting diodes (QLEDs), tandem QLEDs (TQLEDs) have the advantages of long lifetime, high brightness and high efficiency, thereby making them potential candidates for display and lighting applications. In this work, ZnMgO/PEDOT:PSS was employed as the interconnecting layer (ICL) to fabricate TQLEDs, achieving brightness doubling at the equivalent current. Further, the devices exhibited a maximum external quantum efficiency (EQE) of 35.51%, which is currently the largest EQE reported for the full-solution process of manufacturing red TQLEDs. The improvement in TQLED efficiency can be attributed to the optimization of the electronic transport layer (ETL), which is achieved by adjusting the Mg doping level in ZnO. This process facilitated a balanced electron and hole injection and limited the photoluminescence (PL) quenching of QDs by ZnO. Furthermore, it can also be attributed to the effective charge generation capacity of ZnMgO/PEDOT:PSS along with the resistance of ZnMgO to acids. [ABSTRACT FROM AUTHOR]