Bio-sensing and bio-imaging of organisms or molecules can provide key information for the study of physiological processes or the diagnosis of diseases. Quantum dots (QDs) stand out to be promising optical detectors because of their excellent optical properties such as high brightness, stability, and multiplexing ability. Diverse approaches have been developed to generate QDs, while microfluidic technology is one promising path for their industrial production. In fact, microfluidic devices provide a controllable, rapid and effective route to produce high-quality QDs, while serving as an effective in situ platform to understand the synthetic mechanism or optimize reaction parameters for QD production. In this review, the recent research progress in microfluidic synthesis and bio-detection applications of QDs is discussed. The definitions of different QDs are first introduced, and the advances in microfluidic-based fabrication of quantum dots are summarized with a focus on perovskite QDs and carbon QDs. In addition, QD-based bio-sensing and bio-imaging technologies for organisms of different scales are described in detail. Finally, perspectives for future development of microfluidic synthesis and applications of QDs are presented.

Liquid-liquid extraction is an important separation technology in the chemical industry, and its separation efficiency depends on thermodynamics (two-phase equilibrium), hydrodynamics (two-phase mixing and contact), and mass transfer (molecular diffusion). For hydrodynamics, the dispersion size of droplets reflects the mixing of two phases and determines the mass transfer contact area of the two phases. Therefore, a deep understanding of the droplet dispersion mechanism can help guide process intensification. The mass transfer and droplet behaviors in the liquid-liquid extraction process are reviewed based on three scales: equipment, droplets, and the interface between two liquids. Studies on the interaction between mass transfer and other performance parameters in extraction equipment as well as liquid-liquid two-phase flow models are reviewed at the equipment scale. The behaviors of droplet breakage and coalescence and the kernel function of the population balance equation are reviewed at the droplet scale. Studies on dynamic interfacial tension and interaction between interfaces are reviewed at the interface scale. Finally, the connection among each scale is summarized, the existing problems are analyzed, and some future research directions are proposed in the last section.

Hydrogen sulfide (H₂S) removal from various industrial gases is crucial because it can cause huge damage to humans, the environment, and industrial production. Zeolite possesses huge specific surface area and well-developed pore structure, making it a promising adsorbent for H₂S removal. This review attempts to comprehensively compile the current studies in the literature on H₂S removal in gas purification processes using zeolites, including experimental and simulation studies, mechanism theory, and practical applications. Si/Al ratio, cations of zeolite, industrial gas composition and operating conditions, and H₂S diffusion in zeolites affect desulfurization performance. However, further efforts are still needed to figure out the influence rules of the factors above and H₂S removal mechanisms. Based on an extensive compilation of literature, we attempt to shed light on new perspectives for further research in the future.

A continuous synthesis method for the less than 10 nm core-shell upconversion nanoparticles was developed via coiled tube embedded flask reactors and a flow solvothermal co-participation reaction up to 300 °C. Fast nucleation of hexagonal nanocrystals in less than 9 min residence time was achieved owing to the excellent heating ability of the reactors, and a two-step reaction strategy was created for the synthesis of β-NaYF₄:Gd,Yb,Er/Ho/Tm@NaYF₄ particles without intermediate purification.