The mechanism of adsorption and desorption of ethyl cellulose (EC) on and from silver powder was studied. After analysis with DSC, XPS and dynamic FT-IR, which could be heated by a program-controlled heater, applied to observe the states of pure EC and of EC adsorbed on silver powder, and also the thermal decomposition of EC from silver powder, the chemisorption bonding bridge between the 0xygen atoms of EC and the silver atoms investigated. The differences in thermal decomposition between pure EC and EC adsorbed in silver powder were also studied. It was concluded that the ehemisorption bonding between the oxygen atoms of EC and the silver atoms mainly involved the lone-pair electrons of the oxygen atoms on the EC chain and the outer empty 5 sp a hybrid orbital of the silver. Because of the formation of this bridge, the bonds between neighboring carbon and oxygen atoms are weakened. As a result of this effect, the C-O bonds in the EC chain are broken more easily than the C-H bonds, which leads to the observation of--C-H-fragments in the upper space when EC adsorbed on silver is heated. When the same experiments were carried out on pure EC, almost all kinds of broken fragments of the EC molecule, including --C-H-, -C = O-and --C-O--appeared simultaneously.

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Its electric conductivity,spectral transmisivity and color change markly when V2O5 amorphous film is irradited by 308nm laser pulse if the fluence is over the threshold-The films before and after being irradited is surveyed with XRD,XPS and SEM methods, etc-It can be determined that the change of the film is due to irradiation by high fluence excimer laser pulse,the film temperature rises and melts quickly,and then the temperature lowers and the film resolidifies quickly- The quick melting and resolidifying procedure leads to oxygen deficiency in the film,so its stoichiometry changes-