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针对电化学溶解氢传感器铂电极对氢的吸附仍然偏强、铍青铜基底上贵金属敏感膜结合力差且易受铜、铍溶出污染的问题，本文采用脉冲电沉积法在铍青铜基底上制备了不同Pt/Ru/Ir摩尔比的Pt-Ru-Ir三元合金敏感膜，并以纯Pt膜为对照，系统研究了其在40 g/L NaF介质（pH≈9.7）中的氢气氧化反应（HOR）性能。借助X射线衍射（XRD）、扫描电子显微镜与能谱（SEM/EDS）表征了膜的晶相结构、微观形貌与元素分布，并通过循环伏安（CV）、旋转圆盘电极线性扫描伏安（RDE-LSV）结合Koutecky-Levich（K-L）、微极化区Butler-Volmer拟合与Tafel分析，定量评价合金化对HOR动力学的提升。结果表明：Ir的引入可进一步细化晶粒并引起（111）衍射峰高角侧偏移，晶格畸变加剧；在所考察的六种配比中，Pt:Ru:Ir = 4:1:1敏感膜兼具细小均匀的颗粒、致密的膜层与适中的晶格畸变，HOR性能最优。机理上，HOR增强源于Ru、Ir诱导的Pt d带中心下移（电子效应）、Ru/Ir亲氧位点邻近供给OH*（双功能协同）以及晶粒细化与（111）择优取向（几何效应）的三重耦合。本研究为铍青铜基底上低成本、高性能三元合金敏感膜的设计及其在溶解氢传感器中的应用提供了实验依据。

针对联盟链协作中敏感信息披露与业务验证并存的需求，构建基于零知识证明的可验证隐私保护模型，并在 Hyperledger Fabric 上实现原型。模型从内容、身份及元数据与操作关系三个维度组织问题，以消息可验证承诺、交易内容机密性、接收方身份保护和发送方身份保护四个子方案协调既有密码学机制。完整 Marlin 验证置于链下，链码检查授权服务签名及状态条件，状态更新以有效提交为前提。历史功能报告记录 11 类测试、41 个有效用例；系统测试中基础流程与完整隐私流程的平均采样时间分别为 130 ms 和 352 ms。独立协议实验描述了三种所测配置的成本差异。结果支持限定场景下的流程可执行性，但采样时间不能确认为有效提交延迟，也不能分解为单一组件开销。该模型为联盟链中减少直接披露并保留验证证据提供了原型实现，不构成绝对匿名或普遍安全保证。

背景　老年非瓣膜性持续性心房颤动（nPsAF）的发病率持续上升，易导致严重并发症。生活方式干预作为一种低成本、低风险的非药物治疗手段，已被指南推荐为心房颤动的第4种治疗方法，nPsAF的管理不仅需要抗凝与节律控制，更需关注可改变的危险因素。目的　强化生活方式干预对老年nPsAF患者生活质量及综合临床指标的影响。方法　采用前瞻性随机对照研究设计，纳入2023年10月—2024年9月新疆维吾尔自治区4家医院的100例≥65岁nPsAF患者，采用随机数字表法分为对照组（n=50）和干预组（n=50）。对照组患者接受常规综合管理，干预组在此基础上接受强化生活方式干预（涵盖饮食、运动等），比较两组患者干预前和干预12个月后的心房颤动特异性生活质量量表（AFEQT）、欧洲五维健康量表5水平版（EQ-5D-5L），以及饮食和运动情况、血压和血脂控制情况、心电图检查标及血清系统性炎症反应指数（SIRI）等。结果　对照组50例、干预组48例完成了干预及随访。干预前，两组患者AFEQT得分和EQ-5D-5L得分比较，差异无统计学意义（P>0.05）；干预后，两组患者AFEQT得分和EQ-5D-5L得分均较干预前升高，且干预组患者AFEQT得分和EQ-5D-5L得分高于对照组（P<0.05）。干预组患者的AFEQT得分和EQ-5D-5L得分较基线的改善幅度高于对照组（P<0.05），AFEQT得分的Cohen's d=0.838（大效应），EQ-5D-5L的Cohen's d=0.682（中等偏强效应）。干预后，干预组患者的饮食得分高于对照组，收缩压、校正QT间期（QTc）、低密度脂蛋白胆固醇（LDL-C）、SIRI低于对照组（P<0.05）。结论　在常规管理基础上实施强化生活方式干预，能改善老年nPsAF患者的生活质量，在饮食、血压、血脂及炎症状态方面产生积极变化。

Mining activities often lead to drastic alterations in surface structure, and the subsequent vegetation recovery process exhibits significant spatiotemporal heterogeneity. The Changping mining area in Shanxi Province, China was selected as the study region. Leaf area index (LAI) data derived from Sentinel-2A/B multispectral imagery were subjected to time series decomposition. Based on the decomposed series, we applied an improved critical slowing down (CSD) model to calculate two indicators— the first-order autoregressive (AR(1)) coefficient and the detrended fluctuation analysis (DFA) scaling exponent—to assess vegetation resilience. The spatiotemporal variation of vegetation resilience and its correlation with mining-induced disturbances were subsequently analyzed in the six panels in the Changping mining area from 2016 to 2024. The results indicated the following: (1) Overall, LAI in the Changping mining area exhibited a spatial pattern of higher values in the west and lower values in the east. Within naturally vegetated areas, the annual mean LAI increased from 0.891 to 1.172, showing a gradual upward trend over time; (2) Overall vegetation resilience in the Changping mining area exhibited a declining trend. Compared with 2016–2020, the proportion of areas with enhanced resilience increased by 33.97% during 2021–2024, with the most pronounced changes observed in the panels 4 and 5, indicating significant impacts of mining activities. At the working faces scale, the negative effects of mining on vegetation resilience were particularly evident, as resilience during the mining period was substantially lower than that in the corresponding control areas; And (3) mining activities exerted significant disturbances on vegetation resilience in the Changping mining area, with both temporal and spatial gradients. Owing to differences in mining intensity and operational schedules among zones, the responses of vegetation resilience were spatially heterogeneous. Vegetation resilience tended to increase with distance from the actively mined areas, and this spatial difference diminished after mining ceased, indicating a delayed and partially reversible disturbance effect. These findings provide a theoretical basis and a decision-making reference for the protection and restoration of vegetation ecosystems in mining areas.

Farmland shelterbelts play a crucial role in protecting arable land in arid and semi-arid areas, but they may also compete for soil water with crops in agroforestry systems. Film-mulched drip irrigation in adjacent farmland substantially alters the water supply dynamics of shelterbelts, yet studies on the hydrological interactions between farmland shelterbelts and crops under this irrigation regime in the arid oasis areas along the desert margins of Xinjiang Uygur Autonomous Region, China remain limited. This study conducted an experiment in an oasis at the southern margin of the Gurbantunggut Desert in Xinjiang over the 2022–2024 growing seasons. We characterized the evapotranspiration (ET) patterns of the cotton field and adjacent Populus shelterbelt, quantitatively evaluated their interspecific water relationships, and examined fine root distribution to identify the zones and intensity of water competition. The results indicated that during the seedling and flowering–bolling stages, cotton field ET exceeded shelterbelt ET by 56.0%–66.1%; however, during the boll-opening stage, shelterbelt ET was 24.2% higher than cotton field ET. Within the 0.1H–0.5H into the cotton field from the shelterbelt–cotton field interface (where H is the tree height), Populus exhibited a competitive advantage in the 20–40 cm soil layer, with a competitiveness index of 0.083–0.146 (versus 0.039–0.051 for cotton), while competition was weak in the 40–60 cm layer. At 0.1H, Populus root biomass density (RBD) and root length density (RLD) were 1.0–15.2 and 6.0–50.0 times those of cotton, respectively; at 1.0H, cotton RBD accounted for 63.0%–93.5% of total root biomass; and no Populus roots or evidence of water competition were detected at 2.0H and 3.0H. Supplemental irrigation should be applied to cotton fields adjacent to shelterbelts to offset water loss from interspecific competition, particularly during the boll-opening stage. The findings provide a practical basis for optimizing agricultural water management in oasis–desert agroforestry systems under film-mulched drip irrigation and offer regional empirical evidence for global research on water competition in arid-zone agroforestry systems.