To improve accuracy of computer visual inspection in keyboard automatic assembly line, a new two-stage camera calibration method was presented. 2D circle array was used as calibration plate, and centers of the circles were taken as feature points. And feature point coordinates were extracted without human interference. The proposed camera calibration method was divided into two stages. First, lens distortion was neglected, internal and external parameters of the camera were obtained by modified camera calibration toolbox for MATLAB. Then, lens distortion was taken into account, and improved genetic algorithm (GA) was adopted to optimize camera parameters gotten in the first stage. Experiment results indicate the proposed method is feasible, and can meet with requirements of the given application.

A polyamic acid suitable for either pretanning or retanning wet-blue in leather industry has been synthesized by polycondensing pyromellitic dianhydride with diaminodiphenyl ether. Its performances for improving physical properties of crust leather, reinforcing absorption and fixation of chromium were investigated by applying it in a reduced chromium offer system. The results show that the extension and tearing strength, especially thickness of crust leather can be significantly improved by the polyamic acid, and residual chromium in spent tanning bath could be reduced to below 40 mgCr+3/l by pretanning with the polyamic acid. The chromium released from wet-blue during fatliquoring can be reduced by 85.7%, and kept at a much lower limit of 6 mg/l by the polyamic acid. A much fuller crust leather with shrink temperature of over 95°C can be obtained with 3% of normal chrome powder by pretannig or retanning with the polyamic acid. Therefore, this polyamic acid has the good potential for industrial application in ecological leather.

Tannery deliming-bating wastewater contains lots of pollutants including ammonium salt, interfibrillary substances and residual enzymes. In order to reduce the pollution, the wastewater was purified by ultrafiltration with polyimide membrane and recycled in deliming-bating process. Solutes in the wastewater were evaluated by COD, total nitrogen and suspended substance. The effects of ultrafiltration parameters on permeate flux and solute rejections were investigated, and the characteristics of wastewater, as well as membrane cleaning were measured during the recycling. The results show that a steady permeate flux of over 31.5L/m2h with rejections to COD of above 89% and total nitrogen of above 82% can be obtained at 25°C under 0.090MPa in pH7.5 during the ultrafiltration. In the repeated recycling, neither the organic substances nor the nitrogenous substances could be accumulated in operation liquor. The recycling process has the same deliming-bating effect as conventional process. It has good potential for industrial application.

A low molecular weight copolymer suitable for retanning wet-blue in leather industry has been synthesized by copolymerizing maleinuric acid with acrylic acid. Its performances for improving physical properties of crust leather, fixing the free chromium salt existed in wet-blue and scavenging the free formaldehyde introduced by other chemicals were investigated by applying it on goatskin wet-blue. The results show that the strengths and extensions, especially the softness of the crust leather can be significantly improved by the copolymer. The chromium released from wet-blue during retanning and free formaldehyde in leather can be reduced by 84.9% and 70.4% respectively with an offer of 3% the copolymer. Soft leather with very low levels of chromium release and free formaldehyde could be obtained by retanning with this copolymer. Therefore, this copolymer has the good potential for industrial application in ecological leather.

In this paper dipole type optical antenna and V type optical antenna are designed using gold and glass substrates, we compared their resonance properties by finite-difference time-domain (FDTD) method, calculated and analyzed their distribution and field enhancement effects contrastively. The results showed that in the same projected length, the resonant frequency of dipole type optical antenna was higher than the V type optical antenna, while the resonance enhancement factor was lower than the V type optical antenna. These have certain reference significance for researching characteristics of nanoantenna based on surface plasma.