In organic light-emitting diodes (OLEDs), the electron transporting layer plays a very important role in rolling the efficiency, the driving voltage, and the stability of the devices. One of the most important features of the electron transporting materials is the electron-deficient molecular structure. Different types of the electron-transporting materials will have different influences on device performance as well as processing characteristics. In this chapter, the electron-transporting materials based on small molecules, e.g., fluorinated derivatives, imidazoles, quinolines, and pyridines for solution-processed OLEDs, are described and compared. Prospects and developments of the electron transporting material for OLEDs are presented.

In order to improve the working efficiency of the electromagnetic heat storage device under high current and high frequency, the electromagnetic field finite element method is used to analyze and calculate the load circuit to make it in a suitable working state. Firstly, the circuit model of the energy storage device is built by using the field-circuit coupling method and the coil inductance is calculated. Secondly, the harmonic capacitor is analyzed and calculated, so that the load circuit works in a weak inductive state. On this basis, the variation law of loss on the inductor core and the distribution of water temperature rise flowing through the core at a certain water velocity are analyzed. A 50 kW prototype was built using the method proposed in this paper, and the experimental results show that the electro-thermal conversion efficiency of the electromagnetic thermal energy storage device reaches 93.39 %. The feasibility of the design method is proved by experiment and simulation, which has important guiding significance for the research and design of electromagnetic thermal energy storage device. (c) 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

In order to control the outlet temperature of the heat transfer fluid within reasonable range, it is necessary to develop a fast-response and effective control system for the outlet temperature in the parabolic trough solar plants. In this paper, a dynamic mathematical model of parabolic trough collector loop was established first, which took the solar field of a 1 MW solar parabolic trough power plant as the research object. And then an internal model controller (IMC) for the outlet temperature of the heat transfer fluid was proposed based on the developed mathematical model. Afterwards the IMC control system and PID control system were built respectively on the Simulink platform such that. the control effects under multiple disturbances were compared and analyzed accordingly. The results show that: under the disturbances of solar radiation, inlet temperature and ambient temperature, the IMC controller demonstrates better control effect with less time duration for control setting and less overshoot in contrast with the PID controller.

Laser diode pumped solid-state lasers, which have the advantages of high efficiency, compactness, stability, long lifetime and high beam quality etc, are called all-solid-state lasers. The all-solid-state lasers are widely used in military, industrial, medical, scientific research and information fields. Among the many laser crystals suitable for them, the Nd:YVO4 crystal has attracted much attention because of its excellent properties. At the same time, considering the high damage threshold of the nonlinear crystal LBO, using LBO crystal to realize the frequency doubling output of 1342nm fundamental frequency light of Nd:YVO4 laser is an ideal choice. In this paper, an intracavity frequency doubled Nd:YVO4 red 671nm laser based on LBO crystal is reported, and the parameters of this laser are theoretically analyzed. By using a type II noncritically phase-matched LBO crystal, the operation of a red light laser is realized. The output power of 1.16W at 671nm and optical to optical conversion efficiency of 10.5% were obtained at the pump power of 11.0W. The instability of the output power of this laser is less than 1%, and the output mode of it is TEM00 mode. In the experiment, the V-shaped folded cavity structure is used to improve the mode discrimination ability of the laser. Meanwhile, the reflector at the tip of the V-shaped cavity is used as the output mirror to ensure that the fundamental frequency light passes through the frequency doubling crystal twice, which improves the frequency doubling efficiency to a certain extent. This laser has high stability and can meet the needs of many fields for low power lasers, and the configuration of this source makes it very suitable in some kindred systems.

纳米银/聚合物复合材料以其优异的物理化学性质,在近几年得到快速发展,而其在高效抑菌灭菌方面的突出功效更是引起科研人员的广泛关注.本文综述了近年来纳米银/聚合物复合材料的制备方法和抑菌效果的进展,并展望了其未来发展及应用前景.

This paper introduced the principle and characteristic of Inductively Coupled Plasma Atomic E-mission Spectrometry and Inductively Coupled Plasma Mass Spectrometry technology and application on detec-tion and analysis in relevant food.

研究水溶性橘黄素提取工艺及其稳定性,旨在促进水溶性橘黄素的综合利用.通过单因素试验和正交试验确定从橘皮中提取水溶性橘黄素的最佳工艺:料液比1:5 (g:mL),温度50℃,提取时间2.0h.在此最佳条件下,橘黄素提取液的吸光度值为2 661.稳定性试验表明:温度、金属离子、常见食品添加剂、常见氧化剂对水溶性橘黄素影响不大.