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The evolution of normal force on the smooth plate immersed in Newtonian and yield stress fluids was investigated during the dip coating. The influences of withdrawal velocity, liquid rheological property, and plate roughness were elaborated. For all fluids, the variation of force versus the withdrawing height was divided into four stages. Importantly, the control forces for coating in each stage were determined, which are in turn viscous force-capillary, viscous force-gravity, capillary-viscous force, and gravity. The critical value of normal force controlled from capillary to viscous effect during drainage was adopted to calculate the surface tension. The possibility of measuring the surface tension was verified under the negligible interference of viscous effect and film instability through a detailed analysis on the evolution of force in a series of tests. Accordingly, the applicable conditions with the low withdrawal speed, high viscosity, and rough surface were finally achieved. This work can provide a theoretical basis for the film-formation mechanism and surface tension measurement in dip coating. KEYWORDS coatings, shear, tension, viscosity, yielding, 1 | INTRODUCTION Coating a layer of thin film on a solid surface is commonly encountered in industrial production and application, such as environmental protection, medicine, spinning, material protection, magnetization, [...]

Herein we report a unique sandwich-like heterometallic Fe7Sn6 oxo cluster, which features an Anderson-type {Fe7} wheel sandwiched by two {Sn3} layers and is formed via the coordination-induced effect of 2,6-pyridinedicarboxylate. The highly efficient photothermal conversion capability and excellent photothermal stability of Fe7Sn6 demonstrate the potential for solar energy conversion. [ABSTRACT FROM AUTHOR]

Virtual coupling of automated trains has emerged as a promising technology to enhance the operational efficiency and line capacity of railway transportation systems. However, the vulnerability of such systems to malicious cyber attacks poses a significant threat to their stability, reliability and applicability. This article addresses the challenge of ensuring secure virtual coupling control of connected train platoons subject to various cyber attacks, including false data injection attacks, denial-of-service attacks, and replay attacks. First, based on the low-dimensional and noisy sensor measurements, novel set-valued observers are designed for each follower train to estimate their inaccessible full longitudinal motion states despite uncertainties and unknown attacks and noises. Then, distributed secure attack-compensation-based virtual coupling control laws are developed to ensure the platoon's stability and resilience against cyber attacks. Additionally, formal stability analysis of the resultant estimation error system and platoon tracking error system is provided. Furthermore, two algorithms are presented to elaborate the offline observer and controller design process as well as their online implementation. Finally, based on the data of a realistic urban rail transit line, simulation experiments are conducted to validate the efficacy of the proposed theoretical findings. [ABSTRACT FROM AUTHOR]

Atomically precise copper nanoclusters with crystallization‐induced emission enhancement (CIEE) have garnered significant academic interests‐ but the rational design of high‐nuclearity Cu nanoaggregates with precise atomic structures and the CIEE effect remains a long‐standing challenge. Herein, a new atomically precise copper nanocluster co‐protected by thiolate, phosphine, and S2− ligands, formulated as Cu34S6(PFBT)22(PPh3)6 (Cu34, PFBT = pentafluorobenzenethiol, PPh3 = triphenylphosphine), is reported, which possesses a typical Cu12S6 core and a Cu22S22P6 shell. Under photoexcitation at 505 nm, Cu34 exhibits strong red‐light emission with a photoluminescence quantum yield of 4.1%. DFT calculations confirm that the emission stems from the ligand‐to‐metal charge transfer (LMCT) transition. This nanoaggregate shows a strong CIEE effect, with the crystalline form exhibiting an 800‐fold enhancement in emission intensity compared to its solution form. An in‐depth structural investigation of the ligand shell reveals that the extensive C−H···F, C−H···π, and π···π interactions significantly restrict the intra‐ and inter‐molecular rotations and vibrations, accounting for the CIEE phenomena. The red emission of Cu34 can be selectively quenched by CH3CN, with a lower detection limit of 9.36 µM (0.38 ppm). This study advances the development of high‐nuclearity copper nanocluster with the CIEE effect and holds significant potential for applications in selectively sensing volatile organic compounds (VOCs). [ABSTRACT FROM AUTHOR]

Two zero-dimensional hybrid manganese bromide polymorphs ((DMAPH)2MnBr4) exhibit single-crystal to single-crystal phase transformation, accompanied by an increase in MnBr4 tetrahedral bond angle variance (σ2). This structural change leads to an emission redshift due to enhanced crystal field strength, achieving yellow emission with near-unity quantum yield, which highlights its potential for solid-state lighting applications. [ABSTRACT FROM AUTHOR]