Yanzhao Yang

The recovery of Au(III) from aqueous solutions is often hampered by the inherent drawbacks of conventional mechanisms, for instance, anion exchange inevitably introduces secondary pollution, while redox-based methods lead to irreversible degradation of the adsorbent. To overcome these limitations, we designed a cationic piperazine−triazine−based porous organic polymer (I-COP). Its synergistic structure incorporates quaternary ammonium centers for electrostatic attraction and a conjugated diamine–triazine moiety where the electron-deficient triazine fine-tunes the electron density of the adjacent piperazine nitrogen (Npip). This design not only suppresses excessive reducibility but also creates a cooperative dual-nitrogen microenvironment. I-COP exhibits exceptional performance: substantial adsorption capacity at high initial concentrations (e.g., c0 = 2500 mg/L, Qmax = 4870.37 mg/g), outstanding selectivity among precious metals (SFAu/Ag = 3009, SFAu/Pd = 1789, SFAu/Pt = 751), and excellent reusability (>93.35% retention after 17 cycles) without any detectable ion exchange (Br−). A combination of spectroscopic, chromatographic, and DFT studies reveals a novel “capture-reduction-exchange-stabilization” mechanism. After rapid electrostatic pre-concentration, Au(III) undergoes controlled single-electron reduction to Au(I), followed by partial ligand exchange in which two chloride ligands are replaced by the synergistically acting Npip and triazine nitrogen (Ntri), forming an extraordinarily stable mixed-ligand [Au(I)Cl2(Npip)(Ntri)]-type complex. This pathway completely avoids counter‑ion release and minimizes oxidative adsorbent damage. I-COP efficiently recovers trace Au(III) from challenging real matrices including electronic waste(e-waste) leachates and seawater. Beyond presenting a superior adsorbent, this work establishes a new design paradigm: steering metal adsorption toward a thermodynamically favored, ligand-exchange-driven coordination pathway by constructing a cooperative hetero-dinitrogen binding pocket. This principle offers a general strategy for developing robust, sustainable materials for critical metal recovery.

The yield of highland barley is not only related to the food security of Tibet but also to the social stability and development in the frontier region. This study revealed the spatiotemporal distribution of highland barley yield potential using the DSSAT model and GIS technology in the Yarlung Zangbo River and its two tributaries (YZTT) of Tibet from 1981 to 2020, and analyzed its response relationship to climate factors. The results show that the highland barley yield potential ranged from 4284.75 to 7341.15 kg/ha in the YZTT region during 1981 to 2020, with an average of 6719.87 kg/ha. Under the climate change, the highland barley yield potential was on a downward trend of −14.49 kg/ha·a over the past 40 years. In terms of the response of highland barley yield potential to climate change, the highland barley yield potential decreased by 2.90 kg/ha for every 1 MJ/m² decrease in solar radiation. For every 1 °C increase in the maximum temperature, the highland barley yield potential increased by 219.68 kg/ha. Meanwhile, for every 1 °C increase in the minimum temperature, the highland barley yield potential increased by 91.40 kg/ha. These findings aim to provide reference for decision-making in agricultural policy and spatial allocation of agricultural resources.

Bacterial infections severely impede the healing process of infected wounds, and the key challenge to achieving efficient healing of infected wounds lies in precisely regulating the generation and clearance of reactive oxygen species (ROS) across spatiotemporal scales. However, traditional nanozymes struggle to dynamically adapt to fluctuating ROS demands at different stages within the microenvironment. To address this, we designed and synthesized the GO-FePPOP_TFP nanocomposite, which promotes wound healing by dynamically regulating ROS levels through synergistic multienzyme cascade reactions, photodynamic therapy, and photothermal therapy. This composite exhibits outstanding photothermal properties and exceptional photodynamic therapeutic effects, significantly impairing bacterial antioxidant defense capabilities. Furthermore, GO-FePPOP_TFP enables dynamic ROS regulation via near-infrared (NIR) switching. Under NIR irradiation, it exhibits enhanced oxidase-like activity, generating abundant ROS and demonstrating outstanding antibacterial performance. Upon cessation of NIR irradiation, GO-FePPOP_TFP exerts superoxide dismutase-like and catalase-like activities, effectively scavenging residual ROS and alleviating inflammatory responses. Consequently, the cascade self-cyclic enzyme activity system based on GO-FePPOP_TFP coordinates ROS dynamic equilibrium and modulates the inflammatory microenvironment at the wound site, significantly promoting wound healing. This work overcomes the limitation of single-therapy approaches prone to inducing drug resistance, offering important insights for developing highly effective antimicrobial materials to treat infected wounds.

Precious metal recovery from secondary resources with high efficiency and minimal environmental impact remains a critical challenge in separation technology. In this study, a novel ionic liquid N6‐tetramethyl‐N1‐(4‐vinylbenzyl)hexane‐1,6‐diammonium chloride (TVBHDCCl ₂ ) was synthesized and subsequently polymerized into bicentric poly(ionic liquid)s, designated as P(TVBHDCCl ₂ )s. The P(TVBHDCCl ₂ )s demonstrated exceptional adsorption capacities for gold (637 mg/g), palladium (299 mg/g) and platinum (542 mg/g) with fast adsorption kinetics to reach equilibrium within 2–4 min and appreciable stability in acidic medium (pH = 1). Combined experimental and theoretical analyses revealed that the adsorption process is governed by a synergistic mechanism involving electrostatic interactions and redox reactions, with the primary adsorption site located in the region between the double cationic center in P(TVBHDCCl ₂ )s. In summary, this work introduces a highly efficient, selective, and sustainable polymeric adsorbent for simultaneously recovering precious metals from secondary resources, presenting a viable strategy for resource recycling and green separation technology.

自然资源资产价值评估可为自然资源精细化治理与生态产品价值实现提供方法支撑。本文从自然资源资产管理需求出发，围绕价值来源和价值构成两方面阐明其价值内涵，进而界定价值评估范围，梳理评估方法并构建评估流程。评估范围上，以经济价值、生态价值与社会价值三分框架界定土地、矿产、海洋、森林、草原、湿地、水与自然保护地8类自然资源资产的范围，并区分存量与流量两类口径，为综合价值的形成提供分类基础。评估方法上，从评估原则、评估方法、方法选用、量纲协调与边界复核4个相互衔接的环节出发，梳理各类价值评估方法的源流、核算方式、适用条件与局限性，以资产类型和价值识别为起点，结合时间口径、数据基础与管理用途综合判断方法选用方案，并将上述环节组织为面向不同管理需求的可执行评估流程。研究发现，自然资源资产价值分类与方法体系有待完善、本土化与动态化评估参数研究薄弱、复合生态系统多服务协同评估尚未成熟、评估结果与资产管理业务衔接不充分是当前评估实践面临的关键问题；未来需在分门别类构建价值指标体系与评估方法体系、完善流量资本化与边界复核的操作规则、明确水源涵养等关键生态服务参数、构建面向资产单元的动态评估数据库等方向上持续推进，为自然资源资产清查、资产负债表编制、离任审计和生态产品价值实现提供方法参考。

Population distribution and agglomeration patterns are critical indicators of regional economic and social development. Analyzing Nepal's population distribution and agglomeration patterns can provide valuable insights into the underlying spatial distribution, while offering data support and theoretical foundations for formulating effective regional development strategies. This study uses population and land data from Nepal's counties for the years 1981, 2001, and 2021, and employs quantitative analysis methods, including the Gini coefficient, population growth rate, and population concentration index to systematically examine the spatiotemporal evolution and agglomeration patterns. The results show three key insights. (1) The degree of population distribution imbalance has increased, with the Gini coefficient rising from 0.424 in 1981 to 0.531 in 2021. (2) Population growth follows a regional pattern of “rapid growth in the south and slower growth in the north,” with the Terai Plain experiencing rapid expansion, the central mountainous region growing steadily, and the northern highland areas experiencing slow growth. (3) The population concentration displays a tiered distribution pattern of “high concentration in the plains, significant differentiation in the mountainous areas, and extreme sparsity in the high mountain regions”.

China's northeastern black‐soil region is vital for grain production (GP) and is an important ecological barrier in China. Population growth in China has increased the demand for grain, intensifying the competition between arable and ecological land, which may lead to the homogenization and degradation of ecosystem services (ESs) in the black‐soil region's spatial units. However, studies on the trade‐offs among ESs on high‐quality cropland, as well as the spatially explicit mechanisms driving these trade‐offs and synergies, remain insufficient, especially when considering subtle changes in cropland spatial units and environmental heterogeneity. This study investigated the trade‐offs and synergistic relationships between GP and regulatory ecosystem services (RESs) in Northeast China's black‐soil region from 2000 to 2020, and explored the impact mechanisms of these trade‐offs based on the Geodetector and MGWR method. The results showed that all four types of ESs improved over the 20 years, and the total amount of GP and sand fixation (SF) showed a significant upward trend. The relationship between GP and both carbon sequestration (CS) and soil conservation (SC) was mainly synergistic, while the relationship with SF showed a weak trade‐off. The trade‐off intensity between GP and RESs was influenced by multiple factors. Notably, the interaction between GP and CS exhibited a more pronounced dependence on Leaf Area Index dynamics, whereas the trade‐off intensity with both SC and SF was predominantly governed by land‐use intensity patterns. This study serves as a scientific basis for the stable development of regional GP and the optimization of ecological security.