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Reducible metal oxides are selective and effective for C–O bond scission of hydrodeoxygenation reactions via the reverse Mars-van Krevelen mechanism. Creating efficient redox centers while minimizing metal surfaces leads to highly selective catalysts. Single noble metal atoms activate the surface M–O bond, but the catalyst activity is limited due to low loading. Here, we report that the strong metal-support interaction between Ir and CeO2 is facet sensitive, and certain facets regulate the C–O bond cleavage. At 300°C reduction, Ir is mostly encapsulated on an octahedron by (111) facets but remains exposed by (110) facets. The former is selective, whereas the latter is not. Density functional theory indicates that Ir encapsulation is favored on (111) under reaction conditions, and oxygen vacancies more readily form on encapsulated Ir than on pristine ceria.

The active site environment in enzymes has been known to affect catalyst performance through weak interactions with a substrate, but precise synthetic control of enzyme inspired heterogeneous catalysts remains challenging. Here, we synthesize hyper-crosslinked porous polymer (HCPs) with solely -OH or -CH3 groups on the polymer scaffold to tune the environment of active sites. Reaction rate measurements, spectroscopic techniques, along with DFT calculations show that HCP-OH catalysts enhance the hydrogenation rate of H-acceptor substrates containing carbonyl groups whereas hydrophobic HCP- CH3 ones promote non-H bond substrate activation. The functional groups go beyond enhancing substrate adsorption to partially activate the C = O bond and tune the catalytic sites. They also expose selectivity control in the hydrogenation of multifunctional substrates through preferential substrate functional group adsorption. The proposed synthetic strategy opens a new class of porous polymers for selective catalysis.

Intangible cultural heritage is characterized by uniqueness, diversity, locality and ethnicity, and its integration into the narrative landscape design of theme parks is an important way for the inheritance and development of non-heritage culture. The article explores the narrative landscape design techniques used in theme parks and the types of narrative sequences used. Relying on the existing research, the evaluation index system of theme park narrative landscape design is established, the weights of evaluation indexes are solved by the entropy weighting method, and the EWM-TOPSIS model is combined with the TOPSIS method to realize the comprehensive evaluation of narrative landscape design. The satisfaction of narrative landscape design in theme parks in Province Y was analyzed using six theme parks as research objects. The evaluation index for narrative landscape design of theme parks found that aesthetic perceptibility had the most weight at 28.72%, while historical readability had the least weight at 14.27%. The comprehensive evaluation index of the theme park is the highest at 0.314, and the mean values of public satisfaction and importance for the theme park’s narrative intangible cultural heritage landscape design are 3.969 points and 4.049 points, respectively. Narrative landscape design for theme parks that celebrate intangible cultural heritage can help the public experience the charm of intangible cultural heritage.

Lubricant base oils, traditionally derived from non-renewable petroleum, contribute significantly to greenhouse gas emissions. In contrast, oils sourced from furfural and long-chain ketones through aldol condensation and hydrodeoxygenation present a renewable, cost-effective, and environmentally friendly alternative, offering superior cold flow properties. However, the production of long-chain ketones, a crucial component, currently relies on solvent dewaxing in refineries, which is costly and non-selective. One promising biobased approach involves self-ketonization of long-chain fatty acids derived from coconut or palm kernel oils. This method typically employs high boiling point solvents like dodecane or is done in a batch configuration, limiting its scale and industrial viability. This study addresses this bottleneck by eliminating solvents, transitioning to a continuous flow reactor, and achieving kilogram-scale production of long-chain ketones with exceptional selectivity (90%). The lab-scale setup can yield up to 25 kg of 12-tricosanone per month, utilizing earth-abundant MgO as a catalyst. The catalyst underwent slight deactivation due to carbonate formation. Catalyst stabilization, using mixed metal oxides, and regeneration via simple calcination in air are also discussed. Techno-economic analysis (TEA) indicates a 29% lower minimum selling price than the commercial synthetic poly alpha olefin (PAO). Life cycle assessment (LCA) evaluates the global warming potential (GWP) under different environmental assumptions. Under the carbon-neutral assumption for lauric acid production, an 8.9% reduction in GWP was achieved compared to petroleum-based lubricants. [ABSTRACT FROM AUTHOR]

A flame retardant rigid polyurethane foam (FR-RPUF) boasting good mechanical properties is developed by integrating phosphorus-based compounds (DBHP/DMMP) and organically modified microcrystal muscovite (OM-MCM). During foaming, OM-MCM undergoes in-situ exfoliation, yielding RPUF nanocomposites with heightened mechanical strength. The combined deployment of OM-MCM and DBHP/DMMP enables FR-RPUF to achieve an excellent flame retardancy (such as UL94 V-0 rating). This flame retardant effect stems from a bi-phase mechanism: trapping effect of phosphorus-containing radicals in the gas phase and enhanced charring of nanominerals in the condensed phase. Overall, this accessible method enhances flame resistance in RPUF using conventional processes and available materials. [ABSTRACT FROM AUTHOR]

Although vaccines are one of the environmentally friendly means to prevent the spread of ticks, there is currently no commercial vaccine effective against Haemaphysalis longicornis ticks. In this study, we identified, characterized, localized, and evaluated the expression patterns, and tested the immunogenic potential of a homologue of Rhipicephalus microplus ATAQ in H. longicornis (HlATAQ). HlATAQ was identified as a 654 amino acid-long protein present throughout the midgut and in Malpighian tubule cells and containing six full and one partial EGF-like domains. HlATAQ was genetically distant (homology < 50%) from previously reported ATAQ proteins and was expressed throughout tick life stages. Its expression steadily increased (p < 0.001) during feeding, reached a peak, and then decreased slightly with engorgement. Silencing of HlATAQ did not result in a phenotype that was significantly different from the control ticks. However, H. longicornis female ticks fed on a rabbit immunized with recombinant HlATAQ showed significantly longer blood-feeding periods, higher body weight at engorgement, higher egg mass, and longer pre-oviposition and egg hatching periods than control ticks. These findings indicate that the ATAQ protein plays a role in the blood-feeding-related physiological processes in the midgut and Malpighian tubules and antibodies directed against it may affect these tissues and disrupt tick engorgement and oviposition. [ABSTRACT FROM AUTHOR]