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[Objective] To quantitatively study the relationship between land use change and ecosystem service value in Sichuan section of the upper reaches of the Yellow River in the past 20 years, and to evaluate the effect of comprehensive ecological management in this section, so as to provided a basis for improving ethnic regional spatial planning, ecological environmental protection and management, and promoted the high-quality development of the Yellow River Basin. [Methods] Using the land use data of the upper reaches of the Yellow River in Sichuan in 2000, 2010 and 2020, land use change was analyzed based on land use dynamic attitude and land use matrix, and the economic value of the ecosystem service value equivalent per unit area of the terrestrial ecosystem in China was revised. The effects of land use change on the ecosystem service value in the upper reaches of the Yellow River from 2000 to 2020 in Sichuan were quantitatively studied. [Results] (1) From 2000 to 2020, the land use area of forest, desert, wetland and water system in the upper reaches of the Yellow River in Sichuan showed an increasing trend, while the land use area of cultivated land, shrub, grassland and glacial and snow in the upper reaches of the Yellow River showed a decreasing trend, and the land use change in 2010—2020 was more significant than that in 2000—2010. (2) The ecosystem service value of the upper reaches of the Yellow River in Sichuan in 2000, 2010 and 2020, was 1.27×1010, 2.51×1010, 3.92×1010 yuan, respectively, showing an increasing trend. The sensitivity analysis showed that the analysis results were reliable. Amongall land use types, grassland made the most significant contribution to total ecosystem value, and the contribution rate of grassland ecological service was 93.90% and 72.90% in 2000—2010 and 2010—2020, respectively, followed by wetland and forest land. (3) In the study area, the value of each individual ecosystem service showed an increasing trend in the past 20 years, and the sub-value of regional ecological service function was regulatory service>support service>supply service>cultural service. Among the 11 individual functions, the significant service value was climate regulation, hydrology regulation, soil conservation and biodiversity. The sum of the four items accounted for more than 69.50% of the total value. Land use change in the upper reaches of the Yellow River in Sichuan affected the changes of regional ecosystem service value, and grassland was the most significant, followed by wetland and forest land. [Conclusion] The results showed that the results of ecological governance in the past 20 years have been gradually enhanced, and the ecological environment has continuously improved.

Developing smart materials with tunable high‐temperature afterglow (HTA) luminescence remains a formidable challenge. This study presents a metal‐free doping system using boric acid as matrix and polycyclic aromatic hydrocarbons as dopants. This composition achieves dynamically tunable afterglow combining a bright blue HTA lasting for over ten seconds even at 150 °C and an ultra‐long yellow room‐temperature phosphorescence below 110 °C. The observed HTA is attributed to the thermally released exciton recombination within the dopant molecules, which shows excellent temperature tolerance compared to traditional triplet related phosphorescence and thermally activated delayed fluorescence. The planarity of dopants is extensively investigated playing a pivotal role in modulating Dexter electron transfer (ET) for capturing released electrons and thereby affecting the overall performance of tunable HTA. This work provides an efficient and universal doping strategy to engineer tunable HTA through the synergistic action of thermally releasing electrons, Dexter ET and exciton recombination. [ABSTRACT FROM AUTHOR]

Supramolecular organic framework (SOF) has recently garnered significant research interest in the field of luminescent materials. However, SOF with room‐temperature phosphorescence emission in solution is very rare due to the quenching of dissolved oxygen and free molecular motions, which would lead to nonradiative deactivation of triplet exciton in liquid state. In this work, a 3D cationic phosphorescent SOF is synthesized through host‐guest interaction between CB[8] and a tetrahedral monomer TBBP, which can rapidly adsorb anionic guests in solution. When anionic dyes are introduced, triplet to singlet Förster resonance energy transfer (TS‐FRET) in solution can be achieved, and delayed fluorescence with large Stokes shift can be realized. Additionally, when anionic drugs are introduced, the phosphorescence of TBBP‐CB[8] can be quenched due to charge transfer, enabling the detection of drugs through phosphorescence signals. Taking advantage of the fast adsorption property of 3D SOF, an INHIBIT logic gate with three inputs and two outputs is constructed. These findings provide a novel method to prepare phosphorescent functional materials and a new pathway to construct TS‐FRET system in solution. [ABSTRACT FROM AUTHOR]

[Objective] To quantitatively study the relationship between land use change and ecosystem service value in Sichuan section of the upper reaches of the Yellow River in the past 20 years, and to evaluate the effect of comprehensive ecological management in this section, so as to provided a basis for improving ethnic regional spatial planning, ecological environmental protection and management, and promoted the high-quality development of the Yellow River Basin. [Methods] Using the land use data of the upper reaches of the Yellow River in Sichuan in 2000, 2010 and 2020, land use change was analyzed based on land use dynamic attitude and land use matrix, and the economic value of the ecosystem service value equivalent per unit area of the terrestrial ecosystem in China was revised. The effects of land use change on the ecosystem service value in the upper reaches of the Yellow River from 2000 to 2020 in Sichuan were quantitatively studied. [Results] (1) From 2000 to 2020, the land use area of forest, desert, wetland and water system in the upper reaches of the Yellow River in Sichuan showed an increasing trend, while the land use area of cultivated land, shrub, grassland and glacial and snow in the upper reaches of the Yellow River showed a decreasing trend, and the land use change in 2010-2020 was more significant than that in 2000-2010. (2) The ecosystem service value of the upper reaches of the Yellow River in Sichuan in 2000, 2010 and 2020, was 1.27X1010, 2.51 X1010, 3.92X1010 yuan, respectively, showing an increasing trend. The sensitivity analysis showed that he analysis results were reliable. Among all land use types, grassland made the most significant contribution o total ecosystem value, and the contribution rate of grassland ecological service was 93.90% and 72.90% in 2000-2010 and 2010-2020, respectively, followed by wetland and forest land. (3) In the study area, the value of each individual ecosystem service showed an increasing trend in the past 20 years, and the sub-value of regional ecological service function was regulatory service > support service > supply service > cultural service. Among the 11 individual functions, the significant service value was climate regulation, hydrology regulation, soil conservation and biodiversity. The sum of the four items accounted for more than 69.50% of he total value. Land use change in the upper reaches of the Yellow River in Sichuan affected the changes of regional ecosystem service value, and grassland was the most significant, followed by wetland and forest and. [Conclusion] The results showed that the results of ecological governance in the past 20 years have been gradually enhanced, and the ecological environment has continuously improved. [ABSTRACT FROM AUTHOR]