Transition metal dichalcogenides (TMDs) have received considerable attention due to their strong absorption in the near-infrared (NIR) region, strong spin-orbit coupling, and excellent photothermal conversion efficiency (PCE). Herein, CoFeMn dichalcogenide nanosheets (CFMS NSs) are prepared via facile vulcanization of a lamellar CoFeMn-layered double hydroxide (LDH) precursor followed by polyvinyl pyrrolidone modification (to give CFMS-PVP NSs), and found to show excellent photoacoustic (PA) imaging and synergistic photothermal/chemodynamic therapy (PTT/CDT) performance. The as-prepared CFMS-PVP NSs inherit the ultrathin morphology of the CoFeMn-LDH precursor and exhibit an outstanding photothermal performance with a of 89.0%, the highest PCE reported to date for 2D TMD materials. Moreover, 50% of maximum catalytic activity (Michaelis-Menten constant, K m) is attained by CFMS-PVP NSs with 0.26 × 10 −3 m H 2 O 2 at 318 K, markedly lower than the endogenous concentration of H 2 O 2 inside tumor cells. In addition, complete apoptosis of HepG2 cancer cells and complete tumor elimination in vivo are observed after treatment with CFMS-PVP NSs at a low dose, substantiating the NSs' remarkable PTT/CDT efficacy. This work provides a new and facile approach for the synthesis of high-quality multicomponent TMD nanosheets with precise process control, the potential for mass production, and outstanding performance, providing great promise in cancer theranostics.

The combination of chemodynamic therapy (CDT) with photothermal therapy (PTT) is an efficacious strategy in cancer treatment to acquire satisfactory therapy efficiency under endogenous redox reaction and external laser induction....

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Coatings can significantly improve the load-carrying performance of a gear surface, but how they affect the vibration characteristic of the system is an urgent issue to be solved. Taking into account the nonlinear factors like the variable mesh stiffness, friction, backlash, and transmission error, a six-degree-of-freedom spur gear transmission system with coatings is presented. Meanwhile, the finite element method is applied to acquire the time-varying mesh stiffness of the coated gear pair in the engagement process. With the support of the time-history curve, phase curve, Poincare map, and fast Fourier transform spectrum, the dynamic characteristics and the effects of the coating elastic modulus on vibration behaviors of a gear transmission system are minutely dissected by using a numerical integration approach. Numerical cases illustrate that the dynamic characteristic of a gear transmission system tends toward a one-period state under the given operating condition. They also indicate that, compared with softer coatings, stiffer ones can properly enhance the transmission performance of the coated gear pair. Numerical results are also compared with previous studies, and can establish a theoretical basis for dynamic design and vibration control of the coated gear transmission system.

Fluorescent copper nanoclusters (CuNCs) have been drawing great research interest because of their fascinating physicochemical properties. However, the low quantum yield (QY) and poor stability of CuNCs have limited their applications. In this work, CuNCs were anchored onto the layered double hydroxides (LDHs) by the layer-by-layer (LBL) assembly method, and the obtained CuNCs/LDHs ultrathin films displayed an ordered periodic long-range structure and uniform morphology. The CuNCs/LDHs films indicate the strong orange-red emission with higher QY (16.66%) and prolonged fluorescence lifetime (9.05 μs), which is obviously better than that of individual CuNCs. The experimental studies and theoretical calculations both reveal that the location and confinement effects derived from LDHs nanosheets enhance the QY of CuNCs. In addition, the CuNCs/LDHs films are temperature-responsive in photoluminescence (PL) and electrogenerated chemiluminescence (ECL). Consequently, it provides a new and facile approach to fabricate CuNCs-based films accompanied by excellent luminescent properties, which indicate the great potential for temperature sensing applications.

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Novel thin films of (FMN-PSS/LDH)n have been fabricated and displayed dual-stimuli responses to melamine and temperature.