Physicochemical properties, structural properties and gels 3D printing properties of wheat starch.

The relationships between the physicochemical properties of wheat starch and the characteristics of 3D printing were studied by extracting wheat starch from three kinds of wheat flour with different gluten contents. The results showed that wheat starch extracted from high-gluten wheat flour (MS) and medium-gluten wheat flour (ZS) exhibited more accurate printing and better quality than wheat starch extracted from low-gluten wheat flour (JS). ZS had moderate final viscosity and setback value, indicating good extrusion performance and high elasticity. Therefore, the printing quality of ZS was the best, with obvious and unbroken printing lines. The 3D-printed sample made from ZS had dimensions closest to the designed CAD model. Additionally, there were no significant differences in the functional groups of native starch, gelatinized starch, and post-3D-printed starch among the three types. ZS exhibited the most regular microstructure. Therefore, wheat starch extracted from medium-gluten wheat flour was determined to be the most suitable for 3D printing. This research could provide a new theoretical basis for the application of wheat starch in 3D-printed food and offer new technical support for practical production.

Boosting the Performance of Self-Powered CsPbCl3-Based UV Photodetectors by a Sequential Vapor-Deposition Strategy and Heterojunction Engineering.

All-inorganic CsPbCl3 perovskite in ultraviolet (UV) detection is drawing increasing interest owing to its UV-matchable optical band gap, ultrahigh UV stability, and superior inherent optoelectronic properties. Almost all of the reported CsPbCl3 photodetectors employ CsPbCl3 nano- or microstructures as sensitive components, while CsPbCl3 polycrystalline film-based self-powered photodetectors are rarely studied on account of the terrible precursor solubility. Herein, a novel sequential vapor-deposition technique is demonstrated to fabricate CsPbCl3 polycrystalline film for the first time. High-quality CsPbCl3 films with excellent optical, electronic, and morphological features are obtained. A self-powered photodetector based on the CsPbCl3 film is constructed without any charge transport layer, showing a high UV detection performance. A thin p-type PbS buffer layer is further introduced to passivate the surface defects of the CsPbCl3 layer and decrease the interfacial energy barrier by forming a type-II heterojunction, contributing to a faster hole extraction rate and a suppressed dark current level. The best-performing device achieves an ultrafast response time of 1.92 µs, an ultrahigh on/off ratio of 2.22 × 105, and a responsivity of 0.22 A/W upon 375 nm UV illumination at 0 V bias. This comprehensive performance is the best among all of the CsPbCl3 photodetectors reported to date. The as-prepared photodetectors also present an eminent UV irradiation and long-term durability in ambient air. Furthermore, a large-area and uniform 625-pixel UV image sensor is fabricated and attains a prominent imaging capability. Our work opens a new avenue for the scalable production of CsPbCl3-based optoelectronics.

In-line mixing states monitoring of suspensions using ultrasonic reflection technique.

Based on the measurement of echo signal changes caused by different concentration distributions in the mixing process, a simple ultrasonic reflection technique is proposed for in-line monitoring of the mixing states of suspensions in an agitated tank in this study. The relation between the echo signals and the concentration of suspensions is studied, and the mixing process of suspensions is tracked by in-line measurement of ultrasonic echo signals using two ultrasonic sensors. Through the analysis of echo signals over time, the mixing states of suspensions are obtained, and the homogeneity of suspensions is quantified. With the proposed technique, the effects of impeller diameter and agitation speed on the mixing process are studied, and the optimal agitation speed and the minimum mixing time to achieve the maximum homogeneity are acquired under different operating conditions and design parameters. The proposed technique is stable and feasible and shows great potential for in-line monitoring of mixing states of suspensions.

Inline Measurement of Particle Concentrations in Multicomponent Suspensions using Ultrasonic Sensor and Least Squares Support Vector Machines.

This paper proposes an ultrasonic measurement system based on least squares support vector machines (LS-SVM) for inline measurement of particle concentrations in multicomponent suspensions. Firstly, the ultrasonic signals are analyzed and processed, and the optimal feature subset that contributes to the best model performance is selected based on the importance of features. Secondly, the LS-SVM model is tuned, trained and tested with different feature subsets to obtain the optimal model. In addition, a comparison is made between the partial least square (PLS) model and the LS-SVM model. Finally, the optimal LS-SVM model with the optimal feature subset is applied to inline measurement of particle concentrations in the mixing process. The results show that the proposed method is reliable and accurate for inline measuring the particle concentrations in multicomponent suspensions and the measurement accuracy is sufficiently high for industrial application. Furthermore, the proposed method is applicable to the modeling of the nonlinear system dynamically and provides a feasible way to monitor industrial processes.