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Nanosecond (ns)‐pulsed air plasmas are promising for environmental and biomedical applications. This paper presented a low‐cost ns‐pulsed plasma system that consists of a two‐stage Cockcroft–Walton voltage multiplier, a spark gap gas switch, and a plasma reactor. This ns power supply generated a uniform air plasma with a volume of 25 × 25 × 2 cm and a maximum ion wind of 0.8 m/s. The ion wind transported aerosols through plasma volume. Aerosols were charged and deposited on the grounded mesh electrode. The direct interactions between reactive ns plasma and deposited aerosols can promote the development of plasma applications. [ABSTRACT FROM AUTHOR]

This paper describes a methodology to predict the loads generated by a flexible flapping wing. The three-dimensional, whole field wing deformation was first measured using a non-contact optical technique. The measured deformation and motion were then input to a reduced-order model of the flapping wing to calculate the loads generated. Experiments were performed on a thin rectangular plate of 100 mm wing length flapping in air at a frequency of 15 Hz and stroke amplitude of 40°. The wing deformation as well as wing root loads were measured and showed good agreement with previously published data. A direct numerical simulation of the Navier–Stokes equation with exactly the same configuration, but at lower Reynolds number, provided full-field dataset for the development of data-driven reduced-order models. A modified proper orthogonal decomposition-Galerkin method, which includes extra terms to represent moving boundaries, was applied for reduced-order model development. It was found that the reduced-order model with only eight proper orthogonal decomposition modes was sufficient to show good correlation of loads with direct numerical simulations and experimentally measured trends. [ABSTRACT FROM AUTHOR]

Enhancing heavy oil recovery is crucial to ensuring stable crude oil production. The development of stimulus-responsive Janus Pickering emulsifiers tailored for a reservoir environment has garnered significant attention in the field of reservoir production, emerging as a promising alternative to traditional surfactants. In this study, silica-based Janus nanosheets with temperature-responsive properties (OH-SiO 2 -PSBMA JNs) are synthesized using sol-gel process and atom transfer radical polymerization (ATRP) method. Experimental observations reveal that OH-SiO 2 -PSBMA JNs (0.1 wt %) can effectively reduce the interfacial tension (IFT) between heavy oil and water to 23.24 mN/m. Additionally, these nanosheets exhibited excellent emulsifying ability, forming stable emulsions with an average particle size of only 35 μm at a mass fraction of 1 wt % and demonstrating good salt tolerance (Salinity value: 1.51 × 10 4 mg/L). Furthermore, OH-SiO 2 -PSBMA JNs exhibited a temperature response that is well-suited for the reservoir environment, effectively stabilizing heavy oil emulsion at a high temperature (65 °C) and facilitating oil-water separation at a lower temperature (25 °C). These excellent properties of nanosheets contributed to obtaining an additional 13.2% recovery rate at low concentration (0.03 wt %). These results indicated that OH-SiO 2 -PSBMA JNs had the potential for enhanced oil recovery (EOR) application.

Protein-protein interactions are pivotal in numerous biological processes. The computational design of these interactions facilitates the creation of novel binding proteins, crucial for advancing biopharmaceutical products. With the evolution of artificial intelligence (AI), protein design tools have swiftly transitioned from scoring-function-based to AI-based models. However, many AI models for protein design are constrained by assuming complete unfamiliarity with the amino acid sequence of the input protein, a feature most suited for de novo design but posing challenges in designing protein-protein interactions when the receptor sequence is known. To bridge this gap in computational protein design, we introduce ProBID-Net. Trained using natural protein-protein complex structures and protein domain-domain interface structures, ProBID-Net can discern features from known target protein structures to design specific binding proteins based on their binding sites. In independent tests, ProBID-Net achieved interface sequence recovery rates of 52.7%, 43.9%, and 37.6%, surpassing or being on par with ProteinMPNN in binding protein design. Validated using AlphaFold-Multimer, the sequences designed by ProBID-Net demonstrated a close correspondence between the design target and the predicted structure. Moreover, the model's output can predict changes in binding affinity upon mutations in protein complexes, even in scenarios where no data on such mutations were provided during training (zero-shot prediction). In summary, the ProBID-Net model is poised to significantly advance the design of protein-protein interactions., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

A nickel-catalyzed tandem alkoxylation/claisen rearrangement strategy for the oxy-difluoroallylation of ynamides has been developed. In this reaction, 3,3-difluoroallyl alcohol was used as a fluorine-containing building block to construct the C-CF 2 bond for the first time. This approach is recognized for its robust tolerance of functional groups, impressive yields, and excellent atomic efficiency, all achieved under mild reaction conditions. A series of β,β-difluoromethyleneamide derivatives were efficiently obtained through simple operations, and their practicality was confirmed through gram-scale synthesis and product derivatization.

The surface characteristics of stimuli-responsive Pickering emulsifiers can be modified by external environmental triggers, making them highly versatile in various applications. In this study, we report three novel organic-inorganic composite structure emulsifiers. These emulsifiers were designed with a core of magnetic Fe 3 O 4 particles, surrounded by a protective silica layer, and coated on the exterior with three distinct types of modified chitosan (CS). Experimental results demonstrate that these emulsifiers can stabilize emulsion systems consisting of liquid paraffin and deionized water at a concentration of 0.5 wt%. The unique properties of the modified CS coatings allowed for the controlled demulsification of two types of emulsions by adjusting the proton concentration. Additionally, these emulsifiers exhibited magnetic-responsive demulsification under the control of an external magnetic field. The findings of this study provide valuable insights into the design and construction of multi-responsive chitosan-based magnetic Pickering emulsifiers with controllable properties.

By carefully choosing the reaction conditions, we have developed the controllable FeCl 3 - or CuCl 2 -mediated dehydrazinative hydrogenation or chlorination of 3,3-difluoroallyl hydrazines to access α-CF 2 H or α-CF 2 Cl styrenes. The current reaction provides for the first time a facile method for the direct and selective synthesis of α-CF 2 H and α-CF 2 Cl styrenes starting from the same precursors, which is easy to scale up and displays a broad substrate scope and good functional group tolerance. Moreover, product derivatization experiments demonstrated that the resulting α-CF 2 Cl styrenes are practical and versatile building blocks for the diversified synthesis of fluorinated molecules.