The wave function expansion method and singular integral equations are used to investigate the scattering of SH waves by a cylindrical piezoelectric inclusion partially debonded from piezoelectric matrix. For impermeable crack case, dynamic stress intensity factors are obtained and numerical results show the phenomenon of low frequency resonance for various debonding sizes and incident angles.Introduction. The piezoelectric ceramics may contain such defects as cracks etc. resulting from manufacturing process. As the dynamic loading is met, the corresponding fracture analysis becomes a topic of interest on which a few papers presented by Chen[1], Narita[3] and Li [4] have been reported in recent years. Here we consider the scattering problem from a debonded cylindrical piezoelectric inclusion and give the near field solutions that indicate the conspicuous phenomenon of low frequency resonance .The solutions of far fields for same problem have solved by Wang and Yu [5]. Problem. Consider the problem shown inFig.1 where r 0 denotes the inclusion radius, the material parameters of inclusion and matrix are c 1 44 , e 1 15 , 1 11 e and c 0 44 , e 0 15 , 0 11 e respectively. Using cylindrical coordinates(r, , z)(-¡ ¡ ) and take the coordinates of crack tips to be a and b. The motion is time harmonic with frequency and exp(-i t) is omitted for simplicity. The incident wave fields propagate in the 0 -direction have the forms w i 1 (r, )=Aexp[iK 1 rcos( -0 )] i 1 (r, )=e 1 15 Aexp[iK 1 rcos( -0

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X-ray photoelectron spectroscopy (XPS) and FTIR spectroscopy have been employed to investigate the surface electron property and interaction between components of multicomponents hybrid systems Pd -(Fe or Bi) 2 O 3 -polymers. One -way electron transfers from Fe (III) to Pd (0) in Pd-Fe 2 O 3 -polymer and from Pd (0) to Bi (III) in Pd -Bi 2 O 3 -polymer are found, respectively. According to the electron transfer effects, the catalytic activities of Pd-(Fe or Bi) 2 O 3polymer hybrid materials are successfully explained, an electron transfer from Fe (III) to Pd (0) species resulting in an increased activity of the Pd -Fe 2 O 3 -polymer, whereas, that from Pd (0) to Bi(III) species leads to a decreased activity of the Pd -Bi 2 O 3 -polymer. However, FTIR results indicate that there is no strong interaction between palladium (or metallic oxides) and the polymeric supporter, the Pd and Fe 2 O 3 or Bi 2 O 3 are supported on the polymer only by physical adsorption. Finally, based on the above electron transfer concept, the possibilities of theoretical design and preparation strategy of multi-components hybrid catalytic materials by selecting the additive components and regulating their atomic fractions are also discussed.

A study of the energy-mode adjustment and application was presented to investigate the effects of adjustable methods on energy mode. Three methods of energy-mode adjustment were used: by circular profile itself, by an optical scanning expander and deformable mirror. The circular profile naturally modifies energy density with the changes of incident angle. The optical scanning expander was used to turn a Gaussian beam into a uniform beam. Also a novel technique of deformable mirror was designed to obtain a more controllable energy mode for laser selective processing. Moreover, the models describing energy modes were developed to improve laser-processing performance. An experiment was arranged to simulate single-tip diamond truing and produced a result, as shown in the SEM photo, quite similar to a fine thread. The results were discussed to reveal the mechanism of laser processing.

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