DataSheet_1_Measurement of morphological changes of pear leaves in airflow based on high-speed photography.docx

The morphological changes of leaves under the airflow have a significant effect on the deposition of pesticide droplets on the leaves, but the wind-induced vibration of the leaves is complicated to measure. In this study, an aerodynamic test of the pear leaf was conducted in the wind tunnel, and binocular high-speed photography was used to record the deformation and vibration of the leaves under various airflow velocities. Experiments showed that air velocity (v) had a significant effect on the morphological response of the leaf. As v increased, the leaf was in three states, including static deformation, low-frequency vibration, and reconfiguration of airfoil steady state. The mutation from one state to another occurred at the critical velocity of vcr1and vcr2. By tracking the leaf marker point, various morphological parameters were calculated, including the bending angle of the petiole, the wind deflection angle, and the twist angle of leaves under different air velocities. When vcr1 ≤v ≤vcr2, the parameters changed periodically. When vcr1, the petiole and the leaf bent statically, and the bending angle of the petiole and the wind deflection angle of the leaf gradually increased. When v >vcr2, the morphology of the leaf and the petiole was stable. Besides, this study tracked and measured the wind deflection area of leaf, which was consistent with the theoretical calculation results. The measurement of the leaf morphological parameters can reflect the morphological changes of leaves under airflow, thus providing a basis for the decision-making of air-assisted spray airflow.</p

A new isophorone-based ligand and its Ag(I) complex: crystal structures and luminescence

<div><p>An isophorone-based ligand with a delocalized π-electron system, 2-{5,5-dimethyl-3-[2-(pyridine-4-yl)ethenyl]cyclohex-2-enylidene}propanedinitrile (<b>L</b>), was synthesized. By assembling the ligand with AgNO₃, a mononuclear complex [Ag(L)₂]NO₃·H₂O was obtained. Compared with the free ligand, the complex shows superior luminescent properties with large red-shift and longer fluorescence lifetime.</p></div

Unveiling the Impact of Light-Induced Acceptor-Generated ROS on Device Stability in Organic Photovoltaics

The intrinsic stability of the acceptor is a crucial component of the photovoltaic device stability. In this study, we investigated the efficiency and stability of the nonfused-ring acceptors LC8 and BC8 under indoor light conditions. Interestingly, we found that devices based on BC8 with terminal side chains exhibited a higher indoor efficiency and stability. Through accelerated aging experiments, we discovered that the acceptors generate singlet oxygen under light exposure with BC8 demonstrating lower levels of ROS compared to LC8. We attribute this difference to the modulation of the acceptor aggregation orientation. Furthermore, the generated reactive oxygen species (ROS) further deteriorate the acceptor structure, and this phenomenon is also observed in high-efficiency acceptor structures, such as Y6. Our research reveals important mechanisms of acceptor photo-oxidation processes, providing a theoretical basis for enhancing the intrinsic stability of acceptors

Isoreticular Series of 2‑Methylpyridine-Mediated Vinylene-Linked Covalent Organic Frameworks for Efficient Visible-Light-Driven Thiocyanation

Vinylene-linked covalent organic frameworks (COFs) have gained significant attention owing to their outstanding stability, effective π-electron transport, and precise structural tunability, making them promising for visible-light-driven organic transformations. However, the synthesis of vinylene-linked COFs remains challenging, primarily due to the limited availability of monomers with adjustable structures and high reactivity. In this regard, we propose an efficient strategy to expand the repertoire of vinylene-linked COFs by introducing a novel type of tritopic 2-methylpyridine-mediated building block that integrates active methylene sites and tunable functional backbones. By utilizing these tritopic building blocks, a series of isoreticular vinylene-linked two-dimensional (2D) COFs can be readily constructed via a Knoevenagel condensation reaction. The resulting 2D COFs exhibit remarkable crystallinity, stability, and tunable optoelectronic properties, enabling them to function as highly efficient photocatalysts for visible-light-driven thiocyanation reactions. The incorporation of diverse 2-methylpyridine-mediated building blocks would lead to unlocking a plethora of new vinylene-linked COFs, providing unprecedented opportunities to explore the largely unexplored chemistry and properties of this fascinating class of materials

KO^<i>t</i>Bu-Mediated Coupling of Indoles and [60]Fullerene: Transition‑Metal-Free and General Synthesis of 1,2-(3-Indole)(hydro)[60]fullerenes

Direct coupling of indoles with C₆₀ has been achieved for the first time. Transition-metal-free KO^<i>t</i>Bu-mediated reaction of indoles to [60]­fullerene has been developed as a practical and efficient method for the synthesis of various 1,2-(3-indole)­(hydro)[60]­fullerenes that are otherwise difficult to direct synthesize in an efficient and selective manner. This methodology tolerates sensitive functionalities such as chloro, ester, and nitro on indole and builds molecular complexity rapidly, with most reactions reaching completion in <1 h. A plausible reaction mechanism is proposed to explain the high regioselectivity at the 3-position of the indoles and the formation of 1,2-(3-indole)­(hydro)[60]­fullerenes

Regulating Donor–Acceptor Interactions within 2‑Methylpyridine-Mediated Vinylene-Linked Covalent–Organic Frameworks for Enhanced Photocatalysis

Vinylene-linked covalent–oganic frameworks (COFs), as novel photocatalysts, have garnered considerable attention due to their exceptional stability, remarkable π-electron delocalization, and precisely customizable structures. However, the design of novel monomers for constructing vinylene-linked COFs with tunable electronic structures is still in its early stages and poses a number of challenges. Addressing this, a tritopic monomer was developed by attaching a 3-fold 2-methylpyridine unit to the triphenyl-1,3,5-triazine core. The tritopic monomer was further condensed with tritopic aromatic dialdehydes via a solid-state Knoevenagel polycondensation reaction to form two vinylene-linked 2D COFs (TP-PB and TP-PT COF), which exhibited excellent crystallinity, preeminent stability, and outstanding π-electron delocalization. More importantly, by modulation of the donor–acceptor (D–A) interaction within the COFs, the semiconducting properties of the two COFs could be optimized. Due to the stronger D–A interactions in the TP-PB COF containing 1,3,5-triphenylbenzene unit than the TP-PT COF containing triphenyl-1,3,5-triazine unit, the TP-PB COF exhibited broader visible light absorption, narrower band gap, stronger photocurrent response, and lower charge transfer resistance, which makes the TP-PB COF a more efficient photocatalyst for the photocatalytic selective conversions of organic sulfides to sulfoxides and C-3 thiocyanation of indole derivatives with high catalytic activity and recyclability. This work not only demonstrates the construction of vinylene-linked via 2-methylpyridine Knoevenagel polycondensation but also presents a facile strategy for regulating the semiconducting properties of such COFs by fine-tuning the donor–acceptor (D–A) interactions within the COF matrices

Systematic Study and Imaging Application of Aggregation-Induced Emission of Ester-Isophorone Derivatives

The dicyanoisophorone derivatives show obvious AIE behaviors in our previous work. To study the bioimaging application of these chromophores with AIE/AIEE properties, the ester groups substituted for one cyan to form a new family based on isophorone (2a–2e). 2a–2d exhibit obvious AIE/AIEE phenomena, while 2e shows fluorescence quenching in the aggregate state. The morphology and size of aggregates with different water contents were investigated using SEM and DLS, indicating that a large number of smaller globular or quadrate nanoparticles with average diameters in the range 78.79–392.7 nm in mixed solutions are related to these AIE/AIEE or ACQ behaviors. We also made comparative analyses of their optical properties in different states. The crystal data of 2a–2d reveal that the multiple intra- and intermolecular interactions leads to the molecular conformation being more stable, increases the planarity of compounds, restricts the intramolecular motions, and promotes the formation of J-type aggregate, enabling chromophores 2a–2d to emit intensely in the solid state. In addition, the frontier molecular orbital energy and band gap calculated by density functional theory are quite consistent with the experimental results. Finally, these AIE/AIEE-active compounds could be used in bioimaging applications, which immensely provide a new strategy to the application of some AIE/AIEE systems

Pt–N Coordination Rendering the Chemotherapeutic Agent with Photoactivated ROS Generation and Self-Reporting Cell Uptake

The performance of chemotherapeutic agents has been largely restrained by the dose-dependent toxic side effects. In this work, cisplatin (CDDP) was endowed with the capability of photoactivated reactive oxygen species (ROS) generation and self-reporting cell uptake via coordination with a small organic molecule MSN. In the resultant MSN–Pt, the Pt–N coordination could obviously enhance the intermolecular charge transfer (ICT) process that allows the integration of fluorescence imaging, photogenerated ROS, and chemotherapeutic performance. The resultant MSN–Pt can recognize between normal and cancer cells and quickly penetrate the cancer cell membrane, self-reporting the cell uptake. Upon light illumination, mitochondria and nuclei were severely damaged. An in vivo mouse model demonstrated that MSN–Pt completely inhibited the tumor growth, exhibiting a higher efficacy compared with that of CDDP. This work provides a facile strategy to develop chemotherapy (CT) drugs for drug-resistant cancers

Systematic Study and Imaging Application of Aggregation-Induced Emission of Ester-Isophorone Derivatives

The dicyanoisophorone derivatives show obvious AIE behaviors in our previous work. To study the bioimaging application of these chromophores with AIE/AIEE properties, the ester groups substituted for one cyan to form a new family based on isophorone (2a–2e). 2a–2d exhibit obvious AIE/AIEE phenomena, while 2e shows fluorescence quenching in the aggregate state. The morphology and size of aggregates with different water contents were investigated using SEM and DLS, indicating that a large number of smaller globular or quadrate nanoparticles with average diameters in the range 78.79–392.7 nm in mixed solutions are related to these AIE/AIEE or ACQ behaviors. We also made comparative analyses of their optical properties in different states. The crystal data of 2a–2d reveal that the multiple intra- and intermolecular interactions leads to the molecular conformation being more stable, increases the planarity of compounds, restricts the intramolecular motions, and promotes the formation of J-type aggregate, enabling chromophores 2a–2d to emit intensely in the solid state. In addition, the frontier molecular orbital energy and band gap calculated by density functional theory are quite consistent with the experimental results. Finally, these AIE/AIEE-active compounds could be used in bioimaging applications, which immensely provide a new strategy to the application of some AIE/AIEE systems

Substituent Group Variations Directing the Molecular Packing, Electronic Structure, and Aggregation-Induced Emission Property of Isophorone Derivatives

A series of new isophorone derivatives (1–5), incorporating the heterocyclic ring or aza-crown-ether group, with large Stokes shifts (>140 nm), have been synthesized and characterized. 1–4 display aggregation-induced emission behaviors, while dye 5 is highly emissive in solution but quenched in the solid state. It was found that the tuning of emission color of the isophorone-based compounds in the solid state could be conveniently accomplished by changing the terminal substituent group. The photophysical properties in solution, aqueous suspension, and crystalline state, along with their relationships, are comparatively investigated. Crystallographic data of 1–4 indicate that the existence of multiple intermolecular hydrogen bonding interactions between the adjacent molecules restricts the intramolecular vibration and rotation and enables compounds 1–4 to emit intensely in the solid state. The size and growth processes of particles with different water fractions were studied using a scanning electron microscope, indicating that smaller globular nanoparticles in aqueous suspension are in favor of fluorescence emissions. The above results suggest that substituent groups have a great influence on their molecular packing, electronic structure, and aggregation-induced emission properties. In addition, fluorescence cell imaging experiment proved the potential application of 5