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To meet the demand for next-generation electronic products with excellent driving ability and high switching speed, using InSnO electrode material as a semiconductor channel layer is one of the attempts to improve the mobility of thin-film transistors (TFTs). However, instabilities in the environment limit the development of high-mobility semiconductors. In this work, an ultrathin hafnium (Hf)-doped InSnO (HITO) layer is prepared with enhanced stability, which is achieved by radio frequency magnetron cosputtering at low temperature. The HITO layer is deposited onto InSnO (ITO) to reduce the oxygen vacancies concentration, and thus, the trapping and detrapping issues at the surface of ITO channel are suppressed, leading to a high mobility of 76.21 cm $^{{2}}\text{V}^{{-{1}}}\text{s}^{-{1}}$ , a low threshold voltage of −0.86 V, and a steep subthreshold swing (SS) of 0.24 V/decade. The HITO layer is insensitive to water and oxygen and effectively blocks the permeability channel layer. The fabricated HITO/ITO TFTs obtain improved stability in positive bias stress (PBS) tests in humidity condition. The threshold voltage shifts under PBS at 85% relative humidity for 3600 s decreased from −8.2 to 0.97 V. This work provides a feasible method for low-cost, high-mobility oxide TFTs, and the whole process temperature control below 150 °C also expands its application in flexible electronic devices.

Despite increasing indium content improves the field-effect mobility of metal–oxide thin-film transistors (TFTs), it is usually accompanied by the deterioration in bias stability. In this work, we achieve enhanced mobility and stability together within a certain range by controlling the sputtering power in the co-sputtering system. Due to the difference in electronegativity and binding energy between indium and zinc, the increase of indium content at lower sputtering power reduces the oxygen vacancy defects and smooth interfacial quality. In0.45Zn0.42Sn0.13O TFTs exhibit excellent stability threshold voltage variation of only 0.58 and −0.12 V under positive bias stress (PBS) and negative bias stress (NBS). However, excess indium could lead to high carrier concentrations in the channel, which introduced new defects, while defects between active and gate insulator (GI) layer interface trap electrons and lead to decreased stability. In addition, the maximum temperature in this work does not exceed 150 °C and the transmittance of all thin films is greater than 80% in the visible range, which has great potential for application in the next generation of transparent flexible electronics. These results indicate that optimizing the ratio of indium doping is an effective strategy for achieving simultaneous enhancement of mobility and stability.

Beany flavor affects sensory experience of soy protein-based food. Deamidation is an effective approach to improve the flavor of soy protein, but excessive hydrolysis has a negative effect on its molecular structure and processing property. In this study, protein-glutaminase (PG; EC 3.5.1.44) was heterologous expressed in E. coliNissle 1917 (EcN) and used to specifically modify soy protein isolate (SPI) for improved flavor properties of textured protein. A fluorescence-based enzyme activity screening method was developed and optimized for fermentation conditions. After screening for optimal fermentation conditions based on cell fluorescence intensity, 3.01 U/mL of PG activity was achieved. SPI was treated with PG (0–24 h), and the degree of deamidation (DD) rapidly increased to 47.4% within 0–2 h. There was no significant decrease in the molecular weight of deamidated SPI (DSPI) after specific deamidation of PG within 0–10 h. The contents of main beany flavor substances (e.g., hexanal, benzaldehyde, and 2-pentylfuran) in DSPI decreased significantly with increasing DD. Compared with soy protein, moderate deamidation did not affect the processing properties and fibrous structure of DSPI in preparing high-moisture extrudates, while the structure of the extrudate decreased after a deamidation time of more than 6 h. This finding developed a safe expression system for PG and provided a promising method to address beany flavor in soy-based meat analogues produced by high moisture extrusion.

A piezoresistive sensor based on ultralight and superelastic aerogel is reported to fabricate MXene/reduced graphene oxide (MX/rGO) hybrid 3D structures and utilize their pressure-sensitive characteristics. The MX/rGO aerogel not only combines the rGO’s large specific surface area and the MXene’s (Ti3C2Tx) high conductivity but also exhibits rich porous structure, which leads to performance better than that of single-component rGO or MXene in terms of the pressure sensor. The large nanosheets of rGO can prevent the poor oxidization of MXene by wrapping MXene inside the aerogel. More importantly, the piezoresistive sensor based on the MX/rGO aerogel shows extremely high sensitivity (22.56 kPa–1), fast response time (<200 ms), and good stability over 10 000 cycles. The piezoresistive sensor based on the MX/rGO hybrid 3D aerogel can easily capture the signal below 10 Pa, thus clearly testing the pulse of an adult at random. Based on its superior performance, it also demonstrates potential applications in measuring pressure distribution, distinguishing subtle strain, and monitoring healthy activity.

To further improve the electrochemical performance for the wearable and microelectronic devices, we reported an all-MXenes zinc ion hybrid micro-supercapacitor (ZIHMSC) with a wide voltage window (1.60 V) based on V2CTxas the cathode and Ti3C2Txas the anode. The flexible V2CTxand Ti3C2Txelectrodes are fabricated by the electrophoretic deposition method, which is simple and conducive to the realization of positive and negative electrodes matching. Benefiting from the synergistic effect of the two MXenes and the unique configuration, our ZIHMSCs also achieve fast ion and electron transfer kinetics, showing better rate capability than the MXene/Zn system. And the ZIHMSCs achieve excellent electrochemical performance, with high area capacitance of 200.1 mF cm−2, well stability over 5,000 charge/discharge cycles, and high energy density of 71.6 μWh cm−2at 400.7 μW cm−2. The reason for the wide voltage window of the ZIHMSC was well revealed by the large work function difference between the two electrode materials of V2CTxand Ti3C2Txand the redox potential of the electrolyte. And the electrochemical energy storage mechanisms are well investigated by ex-situXPS and XRD. In addition, the ZIHMSC displays well flexibility and mechanical property, suffering from 15,000 bending cycles under 90°. The ZIHMSCs can successfully drive digital tubes and meters and enable digital meters to operate for more than 600 s, proving their practical application potential.

Numerical solutions of the steady transonic small-disturbance (TSD) potential equation are computed using the conservative Murman−Cole scheme. Multiple solutions are discovered and mapped out for the Mach number range at zero angle of attack and the angle of attack range at Mach number 0.85 for the NACA 0012 airfoil. We present a linear stability analysis method by directly assembling and evaluating the Jacobian matrix of the nonlinear finite-difference equation of the TSD equation. The stability of all the discovered multiple solutions are then determined by the proposed eigen analysis. The relation of stability to convergence of the iterative method for solving the TSD equation is discussed. Computations and the stability analysis demonstrate the possibility of eliminating the multiple solutions and stabilizing the remaining unique solution by adding a sufficiently long splitter plate downstream the airfoil trailing edge. Finally, instability of the solution of the TSD equation is shown to be closely connected to the onset of transonic buffet by comparing with experimental data.

The electronic structure and ferroelectric mechanism of trichloroacetamide were studied using first principles calculations and density functional theory within the generalized gradient approximation. Using both Bader charge and electron deformation density, large molecular spontaneous polarization is found to originate from the charge transfer cause by the strong “push-pull” effect of electron-releasing interacting with electron-withdrawing groups. The intermolecular hydrogen bonds, NH⋯O, produce dipole moments in adjacent molecules to be aligned with each other. They also reduce the potential energy of the molecular chain threaded by hydrogen bonds. Due to the symmetric crystalline properties, however, the polarization of trichloroacetamide is mostly compensated and therefore small. Using the Berry Phase method, the spontaneous polarization of trichloroacetamide was simulated, and good agreement with the experimental values was found. Considering the polarization characteristics of trichloroacetamide, we constructed a one-dimensional ferroelectric Hamiltonian model to calculate the ferroelectric properties of TCAA. Using the Hamiltonian model, the thermal properties and ferroelectricity of trichloroacetamide were studied using the Monte Carlo method, and the Tc value was calculated.

Battery management system (BMS) is an important role in battery applications. In BMS, the accurate estimation of the state of charge (SOC) of lithium-ion batteries is most important. Open circuit voltage (OCV) is very important for the accurate estimation of SOC. In order to obtain accurate SOC, the relationship between OCV and SOC requires real-time and accuracy. Due to the difference in lithium-ion concentration and battery internal resistance in the lithium-ion battery, OCV has the characteristics of relaxation. It is necessary to study the relaxation behavior of battery OCV. In this paper, the OCV behavior is studied and focuses on the relationship of the time constant and polarization resistance with SOC during relaxation. The results show that, when the SOC is 30%–100%, the time constant and polarization resistance of lithium-ion batteries are the smallest, the performance is the most stable, and the SOC estimation accuracy is the highest. When the battery is overcharged or SOC is low, the performance of the battery is obviously unstable. Finally, it is proposed that the SOC range of the battery can be roughly estimated by calculating the time constant, and the current aging degree of the battery can be judged.