The prepolymer polyurethanes （PUs） based on isophorone diisocyanate （IPDI）, poly（propylene glycol） （PPG）, 1,4-butanediol （BDO） and dimethylopropionic acid （DMPA） were synthesized at 75-80 ℃ for 7-8 hours,...The prepolymer polyurethanes （PUs） based on isophorone diisocyanate （IPDI）, poly（propylene glycol） （PPG）, 1,4-butanediol （BDO） and dimethylopropionic acid （DMPA） were synthesized at 75-80 ℃ for 7-8 hours, using dibutyltin dilauate （DBTDL） as catalyzer, and polyurethane-acrylate hybrid emulsion was prepared after methyl methacrylate （MMA） was polymerized, using potassium persulfate and azobisisobutyronitrile （AIBN） as initiator, respectively. The influences of these factors such as the kind of initiator, the feed method of initiator and the addition of initiator on properties of polyurethane-acrylate were studied. The FTIR and GPC of aqueous polyurethane were analyzed. The FTIR spectra show that the degree of microphase-separate between the soft segments and rigid segments is high. The analysis of molecular weights stated that molecular weights increased most significantly after amine was added. The experimental results reveal that the appearance of emulsion is excellent, the film is harder and the water absorption radio of the film is less when oil-solubility AIBN is used as initiator. The semi-continuous can increase the molecular weight of polymer and the optimum amount of the initiator was 3% for MMA.展开更多
A respirometer has been developed for microbial toxicity tests. The respirometer is based on luminescence quenching by molecular oxygen. The oxygen sensing film consists of luminescent ruthenium complex adsorbed o...A respirometer has been developed for microbial toxicity tests. The respirometer is based on luminescence quenching by molecular oxygen. The oxygen sensing film consists of luminescent ruthenium complex adsorbed on amorphous fumed silica and immobilized inside silicone rubber. The luminescence intensity depends on the oxygen concentration of sample in contact with sensing film. The inhibition effect of heavy metals on the respiration rate of microorganisms can be evaluated by monitoring the luminescence intensity of the sensing film. The toxicity of Cu 2+ , Zn 2+ , Ni 2+ , Cr 3+ , Pb 2+ and Hg 2+ on activated sludge was tested using the respirometer. The results indicated that the proposed method was sensitive to the heavy metals tested in this experiment. It was feasible to use the respirometer for microbial toxicity tests.展开更多
TiO2 nano-particles were synthesized by sol-gel technique and characterized by X-ray diffractometer(XRD)and transmission electron microscope(TEM).Their photo-catalytic activities for formaldehyde(FA)and methyl orange(...TiO2 nano-particles were synthesized by sol-gel technique and characterized by X-ray diffractometer(XRD)and transmission electron microscope(TEM).Their photo-catalytic activities for formaldehyde(FA)and methyl orange(MO)degradation were tested using degradation rate(η)as an evaluation index.Based on the orthogonal test results,the optimal condition for TiO_(2) preparation was obtained.Results showed that particle sizes were in the range of 10–40 nm,and that prepared TiO_(2) had better photocatalytic activity than P25.A simplified model was developed to evaluate the apparent quantum efficiency(Φapp)of this photocatalytic reaction system.展开更多
基金the Bidding Project of the Industrialization Technology of High Performance Polymer Emulsion and-Aqueous Wood Coating from YueGang Key Fields of Technology(No.B10-B2050260)
文摘The prepolymer polyurethanes （PUs） based on isophorone diisocyanate （IPDI）, poly（propylene glycol） （PPG）, 1,4-butanediol （BDO） and dimethylopropionic acid （DMPA） were synthesized at 75-80 ℃ for 7-8 hours, using dibutyltin dilauate （DBTDL） as catalyzer, and polyurethane-acrylate hybrid emulsion was prepared after methyl methacrylate （MMA） was polymerized, using potassium persulfate and azobisisobutyronitrile （AIBN） as initiator, respectively. The influences of these factors such as the kind of initiator, the feed method of initiator and the addition of initiator on properties of polyurethane-acrylate were studied. The FTIR and GPC of aqueous polyurethane were analyzed. The FTIR spectra show that the degree of microphase-separate between the soft segments and rigid segments is high. The analysis of molecular weights stated that molecular weights increased most significantly after amine was added. The experimental results reveal that the appearance of emulsion is excellent, the film is harder and the water absorption radio of the film is less when oil-solubility AIBN is used as initiator. The semi-continuous can increase the molecular weight of polymer and the optimum amount of the initiator was 3% for MMA.
文摘A respirometer has been developed for microbial toxicity tests. The respirometer is based on luminescence quenching by molecular oxygen. The oxygen sensing film consists of luminescent ruthenium complex adsorbed on amorphous fumed silica and immobilized inside silicone rubber. The luminescence intensity depends on the oxygen concentration of sample in contact with sensing film. The inhibition effect of heavy metals on the respiration rate of microorganisms can be evaluated by monitoring the luminescence intensity of the sensing film. The toxicity of Cu 2+ , Zn 2+ , Ni 2+ , Cr 3+ , Pb 2+ and Hg 2+ on activated sludge was tested using the respirometer. The results indicated that the proposed method was sensitive to the heavy metals tested in this experiment. It was feasible to use the respirometer for microbial toxicity tests.
基金supported by the National Natural Science Foundation of China(Grant No.20176013).
文摘TiO2 nano-particles were synthesized by sol-gel technique and characterized by X-ray diffractometer(XRD)and transmission electron microscope(TEM).Their photo-catalytic activities for formaldehyde(FA)and methyl orange(MO)degradation were tested using degradation rate(η)as an evaluation index.Based on the orthogonal test results,the optimal condition for TiO_(2) preparation was obtained.Results showed that particle sizes were in the range of 10–40 nm,and that prepared TiO_(2) had better photocatalytic activity than P25.A simplified model was developed to evaluate the apparent quantum efficiency(Φapp)of this photocatalytic reaction system.
