A novel strain of Micrococcus sp.DUT_AHX,which was isolated from the sludge of a nitrobenzene(NB)-manufacturing plant and could utilize NB as the sole carbon source,was identified on the basis of physiological and bio...A novel strain of Micrococcus sp.DUT_AHX,which was isolated from the sludge of a nitrobenzene(NB)-manufacturing plant and could utilize NB as the sole carbon source,was identified on the basis of physiological and biochemical tests and 16S ribosomal DNA(rDNA)sequence analysis.It can grow at the temperature up to 40℃or in the presence of NaCl concentration up to 12 g/L in Luria-Bertani(LB)medium.The optimal degradation conditions are as follows:temperature 37℃,pH 7.0,and shaking speed 150 r/min.The strain involves a partial reductive pathway due to the release of ammonia and can also utilize 2-aminophenol as the sole carbon source.Furthermore,the enzyme activity tests show that crude extracts of NB-grown strain DUT_AHX mainly contain 2-aminophenol 1,6-dioxygenase activity.The exploitation of salt-tolerant bacteria will be a remarkable improvement in NB bioremediation and wastewater treatment at high salinity and high temperature.展开更多
The rheological properties of salt-tolerant partially hydrolyzed polyacrylamide(HPAM)solutions with molecular of 2.5×107 g/mol at different concentrations were measured in steady-state shear flow mode by Haake Rh...The rheological properties of salt-tolerant partially hydrolyzed polyacrylamide(HPAM)solutions with molecular of 2.5×107 g/mol at different concentrations were measured in steady-state shear flow mode by Haake Rheostress 150 rheometer.Three constitutive equations(Oldroyd four constant model,Guesekus model and FENE-P model) were used for describing the apparent viscosity and first normal stress difference.The apparent viscosity of salt-tolerant HPAM solutions appears a first Newtonian zone when the shear rate is approximately lower than 0.2 s-1.At high shear rate,the HPAM solutions show shear-thinning and elasticity.The results show that the FENE-P model has the best agreement between theoretical and experimental data within the available shear rate range.The material parameters are useful for numerical analysis of polymer solution flow fields.展开更多
文摘A novel strain of Micrococcus sp.DUT_AHX,which was isolated from the sludge of a nitrobenzene(NB)-manufacturing plant and could utilize NB as the sole carbon source,was identified on the basis of physiological and biochemical tests and 16S ribosomal DNA(rDNA)sequence analysis.It can grow at the temperature up to 40℃or in the presence of NaCl concentration up to 12 g/L in Luria-Bertani(LB)medium.The optimal degradation conditions are as follows:temperature 37℃,pH 7.0,and shaking speed 150 r/min.The strain involves a partial reductive pathway due to the release of ammonia and can also utilize 2-aminophenol as the sole carbon source.Furthermore,the enzyme activity tests show that crude extracts of NB-grown strain DUT_AHX mainly contain 2-aminophenol 1,6-dioxygenase activity.The exploitation of salt-tolerant bacteria will be a remarkable improvement in NB bioremediation and wastewater treatment at high salinity and high temperature.
基金Project(07JCZDJC02600) supported by the Natural Science Foundation ofTianjin,China
文摘The rheological properties of salt-tolerant partially hydrolyzed polyacrylamide(HPAM)solutions with molecular of 2.5×107 g/mol at different concentrations were measured in steady-state shear flow mode by Haake Rheostress 150 rheometer.Three constitutive equations(Oldroyd four constant model,Guesekus model and FENE-P model) were used for describing the apparent viscosity and first normal stress difference.The apparent viscosity of salt-tolerant HPAM solutions appears a first Newtonian zone when the shear rate is approximately lower than 0.2 s-1.At high shear rate,the HPAM solutions show shear-thinning and elasticity.The results show that the FENE-P model has the best agreement between theoretical and experimental data within the available shear rate range.The material parameters are useful for numerical analysis of polymer solution flow fields.
