Amorphous silicon (a-Si) film crystallized by Ni-induced lateral crystallization under static electric field was analyzed. It has been demonstrated that Ni-induced lateral crystallization of a-Si is directional with electric field. Moreover, there exists a critical value of electric field strength, below which the rate of Ni-induced lateral crystallization of a-Si increases remarkably with the increase of field strength, while above which the rate will decrease instead. This phenomenon can be interpreted well based on electromigration effect.

Various negatively charged and positively charged inorganic nano-materials have been suggested to constitute the so-called microparticle retention systems with cationic or anionic polymers. Anionic microparticle retention systems consisted of cationic polymers and negatively charged inorganic nano-materials with various aspect ratios were reviewed while their working mechanism were analyzed. Cationic microparticle retention systems made up of either naturally or organo-modified cationic nano-materials were introduced.

A compact bandpass filter has been investigated in this paper, the filter has four stepped impedance resonators, six open stubs are loaded on the two inner resonators, by adjusting sizes of six open stubs, a wide passband can be obtained. This proposed filter contributes respectively one transmission zero on either side of the wide passband. The proposed topology is demonstrated with a design operating at 5.205 GHz with 20.2% bandwidth, and more than 20dB of spurious suppression from 0 to 4.26 GHz and from 6.27 to 8.85 GHz is demonstrated in experimental results, which match well with the simulated results.

To obtain an adjustable passband filter, one open stub with three branches is loaded on an open loop resonator. The first and the third passband frequencies of the tri-band filter can be flexibly controlled by tuning lengths of three branches, whereas the second passband frequency is fixed. The fabricated filter has good tri-passband performance at 2.19, 4.26, 6.30 GHz. Measured results agree well with the simulated ones.

Both underlay spectrum sharing radios and overlay spectrum sharing radios have their advantages and disadvantages. Ultra wide band (UWB) and cognitive radio (CR) are important underlay and overlay technology respectively used as secondary radio systems. In this paper, a cognitive impulse ultra wide band (CIUWB) spectrum sharing radio technology is presented based on impulse UWB and CR.