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Light has profoundly impacted modern medicine and healthcare, with numerous luminescent agents and imaging techniques currently being used to assess health and treat diseases. As an emerging concept in luminescence, aggregation-induced emission (AIE) has shown great potential in biological applications due to its advantages in terms of brightness, biocompatibility, photostability, and positive correlation with concentration. This review provides a comprehensive summary of AIE luminogens applied in imaging of biological structure and dynamic physiological processes, disease diagnosis and treatment, and detection and monitoring of specific analytes, followed by representative works. Discussions on critical issues and perspectives on future directions are also included. This review aims to stimulate the interest of researchers from different fields, including chemistry, biology, materials science, medicine, etc., thus promoting the development of AIE in the fields of life and health.

Spin-center shift (SCS) is a radical process involving 1,2-radical translocation along with a two-electron ionic movement, such as elimination of an adjacent leaving group. Such a process was initially observed in some important biochemical transformations, and the unique property has also attracted considerable interest in synthetic chemistry. Experimental, kinetic, as well as computational studies have been performed, and a series of useful radical transformations have been developed and applied in organic synthesis based on SCS processes in the last 20 years. This Perspective is an overview of radical transformations involving the SCS mechanism.

Aqueous zinc ion batteries are promising candidates for large scale energy‐storage due to their combination of inherent security and abundant reserves. The Zn metal undergoes continuous plating and stripping during electrochemical cycling, accompanied by parasitic side reactions and dendrite growth, which severely impedes the commercialization of batteries. Here, an innovative strategy is introduced in electrolyte engineering, dedicated to enhancing the stability at the Zn/electrolyte interface. Theoretical calculations and in situ experimental analyses collectively demonstrate that methyl sulfonyl methane (MSM) additives are beneficial in jointly modulating the hydrogen bonding network and the Zn2+ solvation structure, which in turn restricts H2O activity at the interface. Concurrently, the preferential adsorption of MSM on the Zn surface facilitates the controlled growth of compact zinc layers while suppressing dendritic and parasitic reactions. By modulating the electrolyte and managing the electrode interface, the Zn||Zn symmetric battery can be reversibly cycled over 150 days at a current density of 2 mA cm−2, and the assembled Zn||Cu half‐batteries show impressive cycling stability over 3100 cycles. This study provides an in‐depth comprehension of the Zn2+ plating/stripping behavior, and the development of sophisticated electrolyte systems offers practical guidance for constructing high‐performance zinc‐based batteries. [ABSTRACT FROM AUTHOR]

In this study, we experimentally explored the impact outcomes of droplets under a wide range of Weber numbers (0.2 ≤ We ≤ 200) and contact angles (91° ≤ θ ≤ 162°). Five impact outcomes were identified: deposition, rebound, partial rebound, receding breakup, and prompt splash. Compared to the literature, we gathered more comprehensive data on the impact outcomes at various contact angles, which were then organized into a complete phase diagram. Furthermore, we corroborated the accuracy of these outcomes through comparisons with other studies. We conducted a comprehensive analysis of the associated phenomena and underlying mechanisms of these outcomes. By introducing the concept of surface hysteresis energy, we also proposed identification criteria for partial rebound. This innovative approach provides an important reference for further understanding of droplet impact behavior and provides guidance for future research in this field. [ABSTRACT FROM AUTHOR]

Cascade radical cyclization constitutes an atom‐ and step‐economic route for rapid assembly of polycyclic molecular skeletons. Although an array of redox‐active metal catalysts has recently shown robust applications in enabling various catalytic cascade radical processes, the use of free organic radical as the catalyst, which is capable of triggering strategically distinct cascades, has rarely been developed. Here, we disclosed that the benzimidazolium‐based N‐heterocyclic carbene (NHC)‐boryl radical is capable of catalyzing cascade cyclization reactions in both intra‐ and intermolecular pathways, assembling [5,5] fused bicyclic and [6,6,6] fused tricyclic molecules, respectively. The catalytic reactions start with the chemo‐ and regioselective addition of the boryl radical catalyst to a tethered alkene or alkyne moiety, followed by either an intramolecular formal [3+2] or an intermolecular [2+2+2] cycloaddition process to construct bicyclo[3.3.0]octane or tetrahydrophenanthridine skeletons, respectively. Eventually, a β‐elimination occurs to release the boryl radical catalyst, completing a catalytic cycle. High to excellent diastereoselectivity is achieved in both catalytic reactions under substrate control. [ABSTRACT FROM AUTHOR]

Self-perceived intercultural communication competence and intercultural communication apprehension have been recognized as key factors affecting one's intercultural willingness to communicate, but not much attention has been paid to their simultaneous effects. Through a cross-sectional survey of college students in the United States (N = 281), this study examined the predictive power of self-perceived intercultural communication competence and intercultural communication apprehension on intercultural willingness to communicate, as well as the possible mediating role of intercultural communication apprehension. We found that, after controlling for biological sex, both self-perceived intercultural communication competence and intercultural communication apprehension predicted intercultural willingness to communicate when examined concurrently, with intercultural communication apprehension mediating this relationship. Implications of these results are discussed. [ABSTRACT FROM AUTHOR]

Organoboron compounds demonstrate diverse applications in the fields of organic synthesis, materials science, and medicinal chemistry. Compared to the conventional hydroboration reaction, radical hydroboration serves as an alternative approach for the synthesis of organoborons via different mechanisms. In radical hydroboration, a boryl radical is initially generated from homolytic cleavage of a B–H or a B–B bond, which is then added to an unsaturated double bond to deliver a carbon radical. Subsequent hydrogen atom transfer or reduction of the carbon radical to form a carbanion followed by protonation gave the final product. Over the past few years, numerous efforts have been made for efficient synthesis of boryl radicals and the expansion of substrate scope of the radical hydroboration reaction. Here, we discuss the recent advancement of radical hydroboration and its associated mechanisms. Numerous radical hydroboration strategies employing N-heterocyclic carbene borane, bis(pinacolato)diboron and pinacolborane as the boron source were illustrated. Thermochemical, photochemical and electrochemical strategies for the generation of boryl radicals were also discussed in detail. [ABSTRACT FROM AUTHOR]

Li−CO2 batteries have received significant attention owing to their advantages of combining greenhouse gas utilization and energy storage. However, the high kinetic barrier between gaseous CO2 and the Li2CO3 product leads to a low operating voltage (<2.5 V) and poor energy efficiency. In addition, the reversibility of Li2CO3 has always been questioned owing to the introduction of more decomposition paths caused by its higher charging plateau. Here, a novel "trinity" Li−CO2 battery system was developed by synergizing CO2, soluble redox mediator (2,2,6,6‐tetramethylpiperidoxyl, as TEM RM), and reduced graphene oxide electrode to enable selective conversion of CO2 to Li2C2O4. The designed Li−CO2 battery exhibited an output plateau reaching up to 2.97 V, higher than the equilibrium potential of 2.80 V for Li2CO3, and an ultrahigh round‐trip efficiency of 97.1 %. The superior performance of Li−CO2 batteries is attributed to the TEM RM‐mediated preferential growth mechanism of Li2C2O4, which enhances the reaction kinetics and rechargeability. Such a unique design enables batteries to cope with sudden CO2‐deficient environments, which provides an avenue for the rationally design of CO2 conversion reactions and a feasible guide for next‐generation Li−CO2 batteries. [ABSTRACT FROM AUTHOR]

Reducing the contact time of impacting nanodroplets is of fundamental interest and importance due to its promising potential in various engineering applications, such as self-cleaning and anti-icing. In this work, nanodroplets impacting superhydrophobic surfaces decorated by a rectangular ridge are studied over a wide range of Weber number (We) and different sizes of the ridge via molecular dynamics. Six bouncing modes have been distinguished. The usage of the rectangular ridge significantly enhances the bouncing performance of nanodroplets, including enlarging the We range for bouncing and reducing the contact time. It is especially found that the rectangular ridge leads to an increased contact time compared with the flat surface in the moderate We region. The underlying mechanism of the differential effect of the rectangular ridge on the contact time is compressively elucidated by the retraction dynamics of distinct bouncing modes. Subsequently, the retraction models considering different retraction characteristics are developed for the unsplit case. To promote a universal understanding of the effect of the ridge on the retraction dynamics of nanodroplets, several typical ridge shapes (triangular, cylinder, and semi-circular) are further considered. The retraction models are extended and verified to consider the effect of the ridge shape by introducing the equivalent structure parameters. Based on such a universal understanding, a newly designed shoot-shaped ridge is proposed and can considerably reduce the contact time of unsplit nanodroplets in the moderate We region. [ABSTRACT FROM AUTHOR]

Mono and dichloro‐substituted organic molecules are shown to possess significant roles in various fields, especially in medicinal chemistry. One approach to synthesizing these compounds involves the selective dechlorination of easily prepared trichloromethyl compounds. Nevertheless, developing a practical approach that allows selective mono‐ and dihydrodechlorination is a challenging task. Herein, we introduced a method for selective mono‐ and dihydrodechlorination of trichloroacetamides and acetates which was promoted by two different Lewis base‐boryl radicals. Accordingly, 4‐dimethylaminopyridine (DMAP)‐borane enabled mono‐substitution of chlorine atom by hydrogen while dihydro‐substitution of chlorine atoms was promoted by N‐heterocyclic carbene (NHC)‐boryl radical. Using deuterated Lewis base‐borane as deuterium atom source, mono‐ and dideuterodechlorination were also successfully took place. This protocol features broad substrate scope and operates under mild reaction conditions. [ABSTRACT FROM AUTHOR]

The present study investigates impact of nanodroplets on liquid films with varied film thicknesses over hydrophilic to hydrophobic surfaces via molecular dynamics simulations. A new crown pattern, hollow crown, is observed on medium liquid films for nanodroplets, whereas it is not reported for millimeter-sized droplets. Holes (or hollows) are attributed to capillary vibration of a nanometer-thick liquid film. The occurrence of holes is inhibited effectively for deep liquid films because the cavity thickness is much larger than the amplitude of capillary vibration. Surface wettability has a significant influence on thin and medium liquid films for nanodroplets, whereas it only affects thin liquid films for macrodroplets because the range of solid–liquid intermolecular forces is comparable to the size of droplets when the size of droplets reduces to the nanoscale. Subsequently, the accuracies of the existing macroscale models for predicting the time-dependent crown radius of nanodroplets are tested by simulated results. The results show that the macroscale models cannot capture the time-dependent crown radius of nanodroplets. On the basis of energetics analysis, we prove that the failure of macroscale models is attributed to the distinct difference in viscous dissipation mechanisms between macroscale and nanoscale droplets. [ABSTRACT FROM AUTHOR]

Bouncing droplets on superhydrophobic surfaces is one of the potential methods used for anti-icing. The surface supercooling is a significant parameter influencing the bouncing dynamic. A droplet impacting cold superhydrophobic surfaces is investigated via experimental methods. The influence of the surface supercooling and the Weber number on the impact dynamic is elucidated. Intriguingly, the surface supercooling shows no influence on the spreading time, and the initial retraction time as the heat exchange can be ignored in these processes, while it shows a strong influence on the late retraction time as it can lead to the wetting transformation. To further quantitatively describe the influence of surface supercooling, the relationships of the retraction rate in the late retraction are developed, considering the changes in the receding contact angle caused by the supercooling degree. Finally, the relationship of the contact time is established over a range of Weber numbers (We = 49.37–70.53), surface supercooling (ΔT = 15–24 °C), and droplet sizes (D0 = 2.2–3.2 mm). This work is the first to establish the relationship of the droplet contact time on cold superhydrophobic surfaces, which can provide a quantitative method to calculate the contact time for anti-icing. [ABSTRACT FROM AUTHOR]

Rising nanoscale technologies arouse interest in investigating the impact dynamics of nanodroplets. In this work, the impact of nanodroplets on solid spheres is investigated by the molecular dynamics simulation method, to comprehensively report outcome regimes and reveal the curvature effect, in wide ranges of Weber numbers (We) from 1.5 to 235.8, diameter ratios (λ) of nanodroplets to solid spheres from 0.3 to 5, and contact angles (θ) from 105° to 135°. Five outcomes are identified, including deposition, bouncing, splash, covering, and dripping. The former three outcomes are found in the high diameter ratio range (λ > 1), showing similar dynamic behaviors with impacts on flat surfaces, whereas in the low diameter ratio range (λ ≤)1, splash disappears, and covering and dripping take place additionally. At each contact angle, the outcomes are recorded in λ-We phase diagrams. It is found that the bouncing, splash, covering, and dripping are all promoted by decreasing diameter ratios; in addition, the critical Weber numbers for trigging bouncing and splash increase with decreasing θ. However, the critical We of the boundary between the bouncing to other regimes in the low diameter ratio range is not sensitive to wettability owing to the relatively small diameter of solid spheres. For quantitatively describing the curvature effect, the boundaries between the deposition and bouncing regimes in the high diameter ratio range and between the bouncing and other regimes in the low diameter ratio range are established. Both the established models show satisfactory agreement with the boundaries in the phase diagrams. [ABSTRACT FROM AUTHOR]

A sequential asymmetric conjugate addition/cyclisation of α-bromohydroxamates with para-quinone methide derivatives has been developed, which provides enantioenriched 1,4-benzoxazepines in generally high yields (up to 95%) and good enantioselectivities (up to 97 : 3 er). This protocol not only offers a novel and straightforward strategy for constructing chiral 1,4-benzoxazepines, but also demonstrates the potential of α-bromohydroxamates as three-atom synthons in asymmetric cyclisation reactions. [ABSTRACT FROM AUTHOR]

Bouncing droplets on solid surfaces is of great significance in diversified applications such as anti-icing and self-cleaning. It is important to establish a unified model to predict whether an impacting droplet can rebound from a surface or not. This work focuses on the rebound dynamic of a droplet impacting a hydrophobic surface via theoretical methods. Based on energy conservation, a new theoretical model to predict the rebound behavior of an impacting droplet is established. For an ideal surface, the contact angle hysteresis Δθ can be ignored and the rebound condition is θ ≥ θc,i, where θ is the equilibrium contact angle and θc,i is the critical rebounding contact angle (CRCA) of an ideal surface. For a real surface, Δθ is considered and the rebound condition is θr ≥ θc,r, where θr is the receding contact angle and θc,r is CRCA of a real surface. Especially, when Δθ is not large enough, the rebound condition for a real surface can be expressed as θr ≥ θc,i. This work is the first to establish the theoretical model considering both the energy dissipation throughout the impact process and the contact angle hysteresis, which shows a higher consistency with the previous works. [ABSTRACT FROM AUTHOR]