Various concentric-ring patterns formed in a water-anode glow discharge operated at atmospheric pressure

Pattern formation is a very interesting phenomenon formed above a water anode in atmospheric pressure glow discharge.Up to now,concentric-ring patterns only less than four rings have been observed in experiments.In this work,atmospheric pressure glow discharge above a water anode is conducted to produce diversified concentric-ring patterns.Results indicate that as time elapses,the number of concentric rings increases continuously and up to five rings have been found in the concentric-ring patterns.Moreover,the ring number increases continuously with increasing discharge current.The electrical conductivity of the anode plays an important role in the transition of the concentric patterns due to its positive relation with ionic strength.Hence,the electrical conductivity of the water anode is investigated as a function of time and discharge current.From optical emission spectrum,gas temperature and intensity ratio related with density and temperature of electron have been calculated.The various concentric-ring patterns mentioned above have been simulated at last with an autocatalytic reaction model.

Synthesis and bulk polymerization kinetics of monomer dehydroabietic acid-(2-acryloyloxy-ethoxy)-ethyl ester

A bulk polymerization monomer dehydroabietic acid-(2-acryloyloxy-ethoxy)-ethyl ester(DHADG-AC) was synthesized from dehydroabietic acid(DHA). The chemical structure of DHA-DG-AC was characterized by1~HNMR,(13)~CNMR, MS and FT-IR. The kinetics of the bulk polymerization of DHA-DG-AC was investigated by Differential Scanning Calorimeter(DSC).Two kinds of kinetic model(nth-order model and autocatalytic model) were used to investigate the polymerization process. The results showed that the experim e nt al DSC c u r ve s w e r e c o n si st e nt wi th t he computational data generated by the autocatalytic kinetic model, and the value of E_a was 95.73 k J·mol^(–1).