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在食品安全问题与数字化转型升级的双重背景下，供应链透明化已从餐饮企业的风险管理工具，演进为品牌形象建设的核心战略资产。本文立足于国家推动餐饮产业数字化的政策环境，首先分析了连锁餐饮企业的数字化实践现状。进而，论文深入探讨了供应链透明化的多层本质与公众的隐性需求，系统阐述了其通过战略性信任构建与品牌价值叙事对品牌形象的积极作用。通过“西贝事件”的反例，本研究揭示了数字化能力缺失导致的透明化困境。最终，论文论证了数字化技术对实现实质透明的关键推动作用，并提出企业应通过构建一体化数字平台与主动对接监管，将供应链打造为品牌信任的基石，从而在数字化竞争中赢得可持续优势。

基于钾离子通道折纸风车模型的结构启发，结合DNA分子的多链折叠特性、离子调控机制及遗传信息传递规律，提出四链DNA倒锥形风车模型，突破传统双螺旋模型的线性结构局限。该模型以四链DNA为核心骨架，通过“双梯倒扣”形成类风车的辐射状空间构象，链间通过氢键、碱基堆积作用及离子调控稳定，同时依托“单梯遗传”机制实现遗传信息的精准传递。本文详述模型的构建溯源、结构特征、遗传机制及潜在生物学意义，为DNA多链结构与遗传调控研究提供新视角。

The β-delayed neutron emission probability (Pn) is an indispensable quantity to describe the decay strength of very neutron-rich nuclei and the rapid neutron capture process in nuclear astrophysics. A Long HElium-3 Neutron Array (LHENA), is developed at the Beijing Rare Isotope Facility (BRIF) to initiate Pn measurements using Isotope Separated On Line (ISOL) pulsed beams. LHENA is designed to work in conjunction with a tape driver and different detectors, so that β particles, β-delayed neutrons and γ rays emitted from the implanted nuclei can be measured simultaneously in periodical mode. LHENA consists of 21 long 3He proportional counters embedded in a polyethylene-made moderator in two-ring structure, which allows for a flat neutron detection efficiency up to 3 MeV according to our Geant4 simulation. The detection efficiency has been experimentally determined to be 16.4(±0.4)% using the 51V(p,n)51Cr reaction for neutron energies in the 120-700 keV range. A good flatness in neutron detection efficiency and very low background of LHENA are verified, which lay a solid foundation for the first Pn measurement using very neutron-rich Rb isotopes at BRIF.

The extraction of uranium from seawater is crucial for sustainable nuclear energy but remains challenging due to low concentration, carbonate competition, and energy-intensive processes. Herein, this study developed and systematically evaluated a novel electrode material, CF@MTPN, coupled with the energy-efficient double potential step technique (DPST) for the highly efficient extraction of uranium from seawater. CF@MTPN was fabricated through sequential self-assembly of iron-tannic acid (Fe-TA) network and an iron-phytic acid (Fe-PA) complex on carbon felt. In simulated seawater (5 mg L -1 uranyl, 2 mM Na 2 CO 3 , pH 8.1), CF@MTPN achieved rapid uranium removal efficiencies of 90.3% (potentiostatic technique, PST) and 93.3% (DPST) within 15 min, with corresponding extraction capacities of 96.12 and 99.31 mg g -1 d -1 , respectively. Notably, during the DPST process (0 V/-1.3 V), current oscillations led to the detachment of the Fe-PA layer from the control electrode CF@MPN, alongside progressive oxidation of the bare CF surface. In contrast, the introduction of an inner Fe-TA layer in CF@MTPN effectively resolved these stability issues, allowing CF@MPN to maintain its structural integrity throughout an extended DPST operation. Moreover, DPST dramatically enhanced the Faradaic efficiency by 430% over PST by effectively suppressing the competing hydrogen evolution reaction. Practical viability was confirmed through a continuous-flow experiment with 20 L of natural seawater, achieving a uranium recovery of 60.0 μg and a high extraction capacity of 3.62 mg g -1 d -1 over 5 h. This work presents a synergistic material and process solution for efficient, stable, and energy-conscious uranium extraction from seawater.

人工制备煤样,通常使用二分器往往由于初始煤量与二分器定比例缩分不适配，无法获得与国家标准要求的质量一致的煤样。本文主要介绍一种使用二分器将不同级别煤样混合缩分的制样方法--错级缩分；通过理论计算对比错级缩分煤样与逐级缩分煤样的精密度、正确度及准确度，并以试验比对分析两种缩分方法的煤质数据差异，从而得出该方法是否可行的结论。