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The superconducting magnet, as a main component of the international thermonuclear experimental reactor (ITER), is critical to the ITER's long-term stability. Polyimide (PI) not only has excellent electrical properties at cryogenic temperature, but also has strong irradiation resistance, which has become the common choice of insulating materials for the superconducting magnet. Due to the pulsed power supply used in the ITER, PI is facing the dual challenges of cryogenic temperature and pulsed voltage. The surface charge characteristics of irradiated PI film by different doses of electron beam were studied in this paper. The surface charging is completed under the pulse voltage with 40% relative humidity. The partial discharge initial voltage (PDIV) and breakdown voltage in liquid nitrogen (LN2) were measured by electrostatic voltmeter. The findings indicate that proper irradiation can help to minimize charge accumulation and decrease the trap level. At the same time, the PDIV and breakdown voltage can be increased by irradiation. However, too much irradiation can weaken this influence.

With the rapid development of computer network technology, communication network technology plays an important role in people’s life and work, seeking development space for all walks of life and winning huge profits. It not only makes the communication between people more convenient, but also brings a lot of convenience for people’s study and work. However, there are many problems in the development of communication network technology, which restricts its development. Aiming at these problems, this paper discusses the strategy of maintaining the operation of communication network, and traces its essence.

Few studies have focused on effect of nanoparticles on mechanical properties of PI film at low temperature. In this paper, one king of POSS namely polyphenylsilsesquioxane (PPSQ) was added to PI molecules, and the mechanical property of PI-POSS composites were studied by molecular dynamics. The variation of bulk modulus and shear modulus of the composites at low temperature was analyzed. Bulk modulus and shear modulus of Polyimide-POSS composite model would decrease as the temperature rose. Compared with the pristine PI model, the bulk and shear modulus of composite model was smaller.

Superconducting magnet is an important portion in international thermonuclear experimental reactor (ITER). The reliability of superconducting magnet is of great significance for the stable operation of ITER. Due to its excellent cryogenic electrical properties, low thermal shrinkage stress and strong radiation resistance, polyimide (PI) is often used as the insulating material for superconducting magnet. Since a pulse power is used to drive ITER device, PI faces the dual challenge of low temperature and pulse voltage. It is easy to cause charge accumulation and lead to insulation breakdown. This article studied the surface charge and discharge features of PI irradiated by electron beam of various doses under repetitive pulse voltage. The irradiation doses are 0, 300, 500 and 700 kGy. The surface charging was finished with a 40% relative humidity under pulse voltage. The electrostatic voltmeter was employed to collect surface potential data. The results show that moderate irradiation can promote the surface charge decay, reduce the charge accumulation, and make the trap level of PI shallower. Nevertheless, excessive irradiation can weaken the effect.

The effects of CO on the catalytic activities of Ag/Al2O3 for NOx reduction by propane were investigated. Unlike on 1% Ag/Al2O3, the significant promotion effect of CO was observed on Ag catalyst with higher Ag loading. The presence of CO obviously broadened the operation window of C3H8-SCR on 5% Ag/Al2O3, and the temperature range was expanded from 425–510 °C to 375–545 °C. CO did not involve in NO reduction directly. In situ DRIFTS in different feed gases showed that the presence of CO promoted the partial oxidation of C3H8 on 5% Ag/Al2O3 and led to the obvious increases in the amount and variety of intermediate species of C3H8 partial oxidation, namely the enolic and acetate species, which promoted NOx removal significantly.

The phenolic-novolac-Zinc composite materials with hexamethylenetramine (HMTA) 8 wt% at Zinc powder content weight from 2% to 11% are investigated by Scanning Electron Microscope, Differential Scanning Calorimetry, Thermogravimetric analysis, and Kissinger method. It is found that a nano-porous structure is synthesized in phenolic-novolac porous with 8 wt% HMTA and 5 wt% Zn powder. The thermal and anti-corrosion analysis shows that the composite with nano-pores structure produces the highest glass-transtion temperature, decomposition temperature, and the best anti-corrosion property comparing with other samples. Furthermore, it introduces a novel method to prepare the nano-porous phenolic-novolac-Zn composite material which can be used as the functional material. POLYM. COMPOS., 36:1346–1351, 2015. © 2014 Society of Plastics Engineers

Intracellular glucose and lipid metabolic homeostasis is vital for maintaining basic life activities of a cell or an organism. Glucose and lipid metabolic disorders are closely related with the occurrence and progression of diabetes, obesity, hepatic steatosis, cardiovascular disease, and cancer. Chlorogenic acid (CGA), one of the most abundant polyphenol compounds in the human diet, is a group of phenolic secondary metabolites produced by certain plant species and is an important component of coffee. Accumulating evidence has demonstrated that CGA exerts many biological properties, including antibacterial, antioxidant, and anticarcinogenic activities. Recently, the roles and applications of CGA, particularly in relation to glucose and lipid metabolism, have been highlighted. This review addresses current studies investigating the roles of CGA in glucose and lipid metabolism.