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Ce and F were added to MCM-48 molecular sieve by hydrothermal synthesis, and Pd/Ce(F)-MCM-48 metal acid bifunctional catalysts were prepared by impregnation method. The physical and chemical properties of Ce(F)-MCM-48 and Pd/Ce(F)-MCM-48 were characterized by X-ray diffraction, scanning electron microscope, NH3 temperature programmed desorption instrument, Fourier infrared spectrometer, and X-ray photoelectronic spectrometer characterization methods. The results showed that when the molar ratio of the raw materials was n(Ce):n(TEOS) = 0.02 and n(NaF):n(TEOS) = 0.10, Ce(F)-MCM-48-0.10 molecular sieve had a high degree of order and large specific surface area and pore volume, the total acid content increased, and the acid strength also increased. And it had an acidic center and generated certain oxygen vacancies. The catalyst prepared after Pd impregnation had good dispersibility. 0.4% Pd/Ce(F)-MCM-48-0.10 catalyst still maintained the crystalline phase of MCM-48 molecular sieve. A micro-reaction device was used to examine the catalytic performance of n-heptane isomerization of Pd/Ce(F)-MCM-48-0.10 catalysts. When the hydrogen flow rate was 30 mL·min−1, reduction temperature was 300°C, reduction time was 4 h, weight hourly space velocity was 7.6 h−1, and reaction temperature was 280°C, 0.4% Pd/Ce(F)-MCM-48-0.10 catalyst was used in the heptane isomerization reaction, where the conversion of n-heptane was 67.3% and the selectivity of isoheptane was 96.5%.

Ovule abortion significantly contributes to a reduction in chestnut yield. Therefore, an examination of the mechanisms underlying ovule abortion is crucial for increasing chestnut yield. In our previous study, we conducted a comprehensive multiomic analysis of fertile and abortive ovules and found that ACS genes in chestnuts (CmACS) play a crucial role in ovule development. Therefore, to further study the function of ACS genes, a total of seven CmACS members were identified, their gene structures, conserved structural domains, evolutionary trees, chromosomal localization, and promoter cis-acting elements were analyzed, and their subcellular localization was predicted and verified. The spatiotemporal specificity of the expression of the seven CmACS genes was confirmed via qRT–PCR analysis. Notably, CmACS7 was exclusively expressed in the floral organs, and its expression peaked during fertilization and decreased after fertilization. The ACC levels remained consistently greater in fertile ovules than in abortive ovules. The ACSase activity of CmACS7 was identified using the genetic transformation of chestnut healing tissue. Micro Solanum lycopersicum plants overexpressing CmACS7 had a significantly greater rate of seed failure than did wild-type plants. Our results suggest that ovule fertilization activates CmACS7 and increases ACC levels, whereas an overexpression of CmACS7 leads to an increase in ACC content in the ovule prior to fertilization, which can lead to abortion. In conclusion, the present study demonstrated that chestnut ovule abortion is caused by poor fertilization and not by nutritional competition. Optimization of the pollination and fertilization of female flowers is essential for increasing chestnut yield and reducing ovule abortion. [ABSTRACT FROM AUTHOR]

Greening of Northern China and the Tibetan Plateau (NCTP) has been observed by increases in the remotely sensed leaf area index (LAI), driven primarily by CO2 fertilization effects, anthropogenic warming, and the implementation of ecological restoration programs. Continued growth of LAI throughout the 21st century is also projected by the Coupled Model Intercomparison Project Phase 6 (CMIP6) scenarios. However, the question of whether local water resources can sustain ongoing grassland greening has not been adequately investigated. Here we assessed the sustainability of water resources under grassland greening across NCTP under various climate scenarios using water yield (WY, defined as precipitation minus actual evapotranspiration) as the key metric. Unexpectedly, we observe the coexistence of increases in LAI and WY in most of NCTP. In a warming climate with increasing precipitation and CO2, we find that grasses maintain high water use efficiency to sustain their growth, contributing to continued local water resource availability. Thus, livestock production may also continue to increase under the simultaneous growth of LAI and WY in the future. Plain Language Summary: The greening of Northern China and the Tibetan Plateau (NCTP) has been observed through increases in remotely sensed leaf area index (LAI), driven primarily by ecological restoration programs, climate change, and CO2 fertilization effects. While continued growth of LAI throughout the 21st century is projected by Coupled Model Intercomparison Project Phase 6 (CMIP6) scenarios, there is limited understanding of whether local water resources may sustain the ongoing process of grassland greening in the context of more frequent and severe drought conditions under global warming. Using three schemes considering plant physiological and hydrological feedbacks toward climate change, our study unveils changes in regional water sustainability (i.e., water yield) under grassland greening across NCTP over the past four decades and up to the end of the 21st century. Surprisingly, we observe the coexistence of future grassland greening and enhanced water resource availability in most of NCTP. Moreover, increased precipitation from atmospheric transport and evaporation recycling, coupled with a warming climate and rising CO2 levels, enables grasses to maintain high water use efficiency, sustaining their growth and contributing to the availability of local water resources. Additionally, projections suggest that the area occupied by livestock production across NCTP may continue to grow due to the simultaneous improvement in grassland and water resource availability. Key Points: Grassland greening and enhanced water resource availability may coexist in most of NCTP in a warming climateEffects of plant physiological and hydrological factors along grassland greening on water yield in the future were analyzedThe positive influence of enhanced water resource availability and ongoing grassland greening on future livestock production was quantified [ABSTRACT FROM AUTHOR]

n-Alkane hydroisomerization over bifunctional catalysts is an effective approach for clean fuel production. However, achieving metal–acid synergy and enhancing the catalytic performance by the preparation of bifunctional catalysts with suitable proximity between the metal sites and Brønsted acid sites are still challenging. In this work, a series of Pt/SAPO-11 catalysts with different Pt loading applied in n-heptane hydroisomerization was synthesized. SAPO-11 was synthesized by the Instant Exactness Synthesis (IES) method, which, with unique morphology and pore structure, was chosen as support for the hydroisomerization catalysts; Pt/SAPO-11 was synthesized with the impregnation method, Pt nanoclusters with trace loading were fabricated over the SAPO-11 support, and the as-synthesized catalysts with different Pt loading were labeled as xPt/SAPO-11 (x = 0.1, 0.3, 0.5, 0.8 and 1.0). Various characterizations, including XRD, nitrogen adsorption–desorption, SEM, TEM, NH3-TPD and XPS, were carried out on catalysts to obtain deep insights into the microstructure and valence states of xPt/SAPO-11. The catalytic performance of xPt/SAPO-11, including catalytic selectivity and conversion, was investigated in the n-heptane hydroisomerization in detail. Pt loading affected the catalytic properties of xPt/SAPO-11 in the hydroisomerization of n-heptane. The selectivity of 0.5Pt/SAPO-11 toward isomers was about 65% with a conversion of 77% at 310 °C, which was obviously higher than other xPt/SAPO-11 catalysts. [ABSTRACT FROM AUTHOR]

3-Imidazo[1,2-α]pyridine coumarin molecules 3a–3d with four different substituents were synthesised from salicylic aldehyde derivatives, ethyl acetoacetate and 2-aminopyridine derivatives, and exhibited strong blue fluorescence in non-polar solutions and large Stokes shift (184–210 nm) in polar solutions. All these were validated using density functional theory (DFT) and time-dependent density functional theory (TD-DFT). Furthermore, 3a-3d exhibited a solvatochromism effect and solid state fluorescence. The results indicated that the introduction of the 3-imidazo[1,2-α]pyridine group at the 3 positions of coumarin constructed an asymmetric electronic structure, which induced intramolecular charge transfer (ICT) with non-radiative energy enhancement, leading to large Stokes shifts. Meanwhile, by introducing an electron-donating group into imidazo[1,2-α]pyridine, the HOMO (highest occupied molecular orbital)–LUMO (lowest unoccupied molecular orbital) gap can be narrowed to enhance ICT, further increasing the Stokes shift, suggesting a promising and novel model for achieving large Stokes shifts for the development of coumarin dyes. [ABSTRACT FROM AUTHOR]