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Due to the absence of the functional group in the poly (p-xylylene) (PPX) based tube, there is limitation of its application such as a catalyst supporter. In this paper a functional tube with a modification of the PPX tube by coating with polyacrylonitrile (PAN) was successfully prepared and its dielectric constant was measured. The results show that the PAN coated PPX tube has an obvious dielectric relaxations, which has no great different with that of a pure PAN film.

This paper analyzed several kinds of isolating DC/DC boost converting circuit. Choose isolating boost full bridge circuit as the main circuit of the DC/DC converter according to the designing requirements. Design the advanced isolating boost converting circuit, and use synchronous rectification in the full bridge rectifying circuit linked to the secondary side of the transformer to reduce the power loss of the main circuit and improve the overall efficiency. Analyze the working principle of the main circuit and the simulation mode. Considering the converter has to deal with huge power and current stress, this paper give instructions on the device selection and design method, including the selection of the lock-in tube MOSFET and transformer of the main circuit. At last, simulation of the system is run by using saber, which proves the theoretical analysis to be reasonable and correct.

Electrospinning of PVA can be performed from aqueous solution leading to the generation of homogenous nanofiber webs. PVA nanofibers are generally required to be modified because of its poor stability in water. The water stability of PVA nanofibers was improved by heat treatment in this paper. The test results showed that the crystallinity of the PVA nanofibers increases after heat-treatment. The crystallinity which is the largest increased by 12% when they were treated at 150°C for 10 min. The heat-treated fibers don’t dissolve in water and show certain degree of agglutination and swelling. PVA nanofibers were taken as the inner layer of the sandwich structure purification material prepared with the hot pressing technology. The filtering experiment showed that the filtration properties were better when the area density of PVA nanofibers is 2.5g/m2. The filtration efficiency of materials and retention rate of PVA nanofibers decreased after being used for 5 times.

Coaxial electrospinning has been recognized as an efficient technique for fabrication of composite fibers with especial circular cross-section in a diameter from micrometers to nanometers. In this paper, PS hollow submicro-fibers have been successfully prepared by electrospinning two polymer liquids through a coaxial, two spinneret, followed by selective removal of the core. Moreover, the influence of the relative (inner-to-outer) flow rate on the morphology and the average diameter of the fibers have been studied. The hollow submicro-fibers are particularly attractive for use in catalysis, purification, separation, gas storage, energy conversion, drug release, sensing, and environmental protection.

The experimental data show that Southeast China Sea has a higher occurrence probability of atmospheric duct. Based on modified refractivity, Neural Network was introduced to predict the duct height of evaporation duct and analyze the anomalous propagation of electromagnetic wave in marine evaporation duct. By Neural Network, Refractivity from Clutter (RFC) is used to predict and forecast the refractive index profile of evaporation duct.

Nano-TiO2 is a high efficient and no poisonous light induced catalyst. It is important how to immobilize it on some supporter for its application. In this paper, The Nylon-6 (PA-6) nanofibres bearing TiO2 nano-particles were prepared via gas-jet/electrospinning technique. The resulted materials were characterized by XRD, SEM, TEM, EDX and TG techniques, and antibacterial activities of the resulted fibers were tested by Shake Flask method. The results show that fibers bearing nano-TiO2, in an average diameter from 60 to 65nm were prepared, and the antibacterial efficiency of these gas-jet/electrospun nanofibers can reach 99.74%. The titled fibers can be loaded in a sandwich structure nanofiber super-cleaning material by hot-press process, and its filtration efficiency can reach 99.50% with 1µm polystyrene microspheres as the filter media.

The polyurethane rigid foam/expanded perlite thermal insulation composites (PPC) have been prepared by mixing the two-component polyurethane and expanded perlite. The effects of proportioning of constituents on the fireproofing performance of PPC were investigated according to maximum flame height using a small scale burner test. The results showed the expanded perlite has a great effect on the flame retardant properties of PPC.

Permanent magnet synchronous motor (PMSM) is a multi-variables, non-linear and strong coupling system. A model reference adaptive controller (MRAC) for PMSM based on back propagation (BP) neural network (NN) is proposed to solve the shortcoming of traditional proportion integration (PI) control method, which is widely used in linear system. According to the proposed method, the simulation model is established and simulated with Simulink. The adaptive control of motor speed is achieved with the training of BP neural network. Simulation results show that the system has long response time, small overshoot and high static performance.

The polyurethane rigid foam/expanded perlite thermal insulation composites (PPC) have been prepared by mixing the two-component polyurethane and expanded perlite. The effects of proportioning of constituents on the mechanical and thermal properties of PPC were investigated. The results showed the compressive strength of PPC was improved and good heat-insulating was achieved, which would promote the application of polyurethane rigid foam and expanded perlite in buildings.