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In order to improve the ability of solid zein particles to stabilize Pickering emulsions, octenyl succinic anhydride (OSA)-modified starch was used to modify zein. Zein-OSA starch composite particles were prepared by solvent-antisolvent precipitation method. The interaction between zein and OSA starch and the size and structure of the composite particles were studied, and the effects of the mass ratio of zein to OSA starch on the particle size distribution, storage stability, pH stability and rheological properties of Pickering emulsion stabilized with the composite particles were explored. The results showed that OSA starch could modify zein through non-covalent interactions including electrostatic interaction, hydrogen bonding and hydrophobic interaction, changing the secondary structure of zein and improving its hydrophilicity. The composite particles with zein to OSA starch ratio of 1:3 had the smallest average particle size (163.3 nm) and PDI (0.177), and its contact angle was 87.4°, which indicated that the particles had nearly neutral wettability and were more suitable for stabilizing Pickering emulsions. Meanwhile, Pickering emulsions stabilized by the composite particles had the smallest particle size distribution and the highest storage modulus, loss modulus and apparent viscosity, indicating that OSA starch modification could regulate the interfacial properties of zein composite particles and consequently of Pickering emulsions. The above studies show that the interfacial modification of zein can improve the stability of its solid particles and consequently of Pickering emulsions. This study provides theoretical support for further expanding the comprehensive utilization of zein in emulsion systems.

Nickel salts of Keggin-type heteropolyacid on Zr(IV)-based metal-organic frameworks (UiO-66) has been synthesized via ion-exchange followed by a facile one-pot hydrothermal method. The synthesized catalysts underwent FT-IR, N2 adsorption-desorption, powder XRD, SEM and TEM analysis. The NiHSiW/UiO-66 catalyst was used as a new and effective solid acid in the catalytic transfer free fatty acid to biodiesel with an optimum conversion of 86.7%. The excellent activity of the NiHSiW/UiO-66 nanocatalyst was closely related to its high specific surface area, nano-sized catalyst, and the synergistic effects of NiHSiW salts and UiO-66 matrix. Importantly, a relatively stable catalytic performance was achieved for 8 repeated cycles. Finally, kinetics of the esterification reaction have been assumed to be of pseudo first order.

Bioinspired two-dimensional (2D) nanofluidic membranes have been explored for the creation of high-performance ion transport systems that can mimic the delicate transport functions of living organisms. Advanced energy devices made from these membranes show excellent energy storage and conversion capabilities. Further research and development in this area are essential to unlock the full potential of energy devices and facilitate the development of high-performance equipment toward real-world applications and a sustainable future. However, there has been minimal review and summarization of 2D nanofluidic membranes in recent years. Thus, it is necessary to carry out an extensive review to provide a survey library for researchers in related fields. In this review, the classification and the raw materials that are used to construct 2D nanofluidic membranes are first presented. Second, the top–down and bottom–up methods for constructing 2D membranes are introduced. Next, the applications of bioinspired 2D membranes in osmotic energy, hydraulic energy, mechanical energy, photoelectric conversion, lithium batteries, and flow batteries are discussed in detail. Finally, the opportunities and challenges that 2D nanofluidic membranes are likely to face in the future are envisioned. This review aims to provide a broad knowledge base for constructing high-performance bioinspired 2D nanofluidic membranes for advanced energy applications. [ABSTRACT FROM AUTHOR]

Non‐contact humidity sensors have been widely explored as human–computer interaction for the internet of things and artificial intelligence. However, except for the existing sensing mechanisms, such as resistive, capacitive, and functional groups gradient based device, little attention has been paid to exploiting new sensing mechanisms with novel properties which can meet the requirements of miniaturization and integration. Here, a self‐powered potentiometric humidity‐transduction mechanism, which modulates the measured potential difference between two electrodes by humidity stimulation on the graphene oxide (GO) solid electrolyte, is reported. On the strength of this mechanism, a highly adjustable potentiometric humidity sensor with sandwich structure of reduced graphene oxide/GO/foamed metal (nickel, zinc, iron and copper), exhibiting good scalability and cost‐efficiency, enabling fast response/recovery (0.8 s/2.4 s), ultra‐high response (0.77 V) and excellent stability (over 1500 cycles) is developed. Unlike traditional sensing mechanisms, the manipulation mechanism raised here shows self‐powered ability with no need for an additional power unit and has ultra‐low power consumption. These results provide a new scheme for the research and development of self‐powered humidity sensors, and these sensors show superior performance in non‐contact sensing applications. [ABSTRACT FROM AUTHOR]

Great efforts have been made to build multifunctional flexible pressure sensing devices to enable future wearable electronics. However, a green‐safe, cost‐effective, self‐powered integrated pressure sensing system remains challenging. Herein, an all‐solid‐state pressure sensing rGM (rGO/GO/PVA nanofibers/MXene) system is designed and developed based on a mechanical potentiometric transduction (MPT) mechanism, which converts mechanical stimulation into the change in the ion transport channel and encodes it into the measured potential difference between two electrodes with hydrated GO, thereby generating potential conduction behavior as well as a programmable stable voltage and current. The self‐powered rGM sensor can yield an output open‐circuit voltage of 0.58 V and a short‐circuit current density of 3.2 µA cm–2 when experiencing a steady mechanical pressure. Unlike typical pressure sensors, rGM sensors have an ultrawide detection range (0.7 Pa–1300 kPa), high stability (maintain 95% performance after 5000 cycles), high adjustability, simple preparation method, implying that the rGM sensor can provide real‐time monitoring for human physiological signals without an external power supply, which has a wide‐range impact on medical care. This work presents a new design based on the MPT mechanism that will significantly simplify manufacturing while improving the performance of future electronic devices and smart systems. [ABSTRACT FROM AUTHOR]

In the present study, phosphomolybdic acid (HPMo) supported on Cu-BTC Metal-organic frameworks (MOFs) were prepared and utilized as a solid acid catalyst. The structure of the synthesized materials was characterized by using powder XRD, FT-IR, N2 adsorption-desorption, SEM, TEM, TG, and NH3-TPD techniques. These results exposed that HPMo was successfully encapsulated in the Cu-BTC cage and the Keggin structure of HPMo was maintained in the composite catalyst. In addition, the catalytic activity and recovery properties of the HPMo/Cu-BTC catalyst for the esterification of oleic acid with methanol into biodiesel were evaluated. These results showed that the HPMo/Cu-BTC catalyst exhibited high conversion (93.7%) and excellent reusability due to its mesoporous structure, excellent acidic activity, high BET surface area, large pore volume, and good thermal stability. Meanwhile, the kinetic studies of the esterification reaction revealed that it follows pseudo-first-order kinetics with a low activation energy of 37.5 KJ/mol. More interestingly, it shows potential application for esterification of free fatty acids (FFAs) or pretreatment of low-cost feedstocks contain high FFAs content for the green production of biodiesel. [ABSTRACT FROM AUTHOR]