Stability of Defibrase in various pH buffer solutions was investigated. Enzyme-linked immuno-sorbent assay (ELISA) and coagulating time method were used to assess antigenic stability and coagulating stability, respect...Stability of Defibrase in various pH buffer solutions was investigated. Enzyme-linked immuno-sorbent assay (ELISA) and coagulating time method were used to assess antigenic stability and coagulating stability, respectively. The change of antigenic activities and coagulating activities of Defibrase in the same buffer solutions (pH 6, 7 and 8, with the exception of pH 3.6) showed similar tendency to decline with the time. Concentrated Defi-brase was relatively stable at neutral pH 6~7, more than 95% of its initial activities (100BUmL-1) was kept after a 10-day storage at 40 oC, whereas in pH 3.6 and pH 9 buffer solutions, diluted Defibrase was very labile. Addition of Triton X-100 or bovine serum albumin could effectively prevent loss of Defibrase by minimizing adsorption of De-fibrase to plastic surface (P<0.005). Concentration of Defibrase could also affect its stability in aqueous solutions.展开更多
The removal of radionuclide from radioactive wastewater has captured much attention.Strontium-90 is one of the major radionuclides.To develop a new type of adsorbents to remove strontium ions from the radioactive wast...The removal of radionuclide from radioactive wastewater has captured much attention.Strontium-90 is one of the major radionuclides.To develop a new type of adsorbents to remove strontium ions from the radioactive wastewater,in this study,novel hybrid membranes were prepared and characterized.The adsorption kinetics,thermodynamic parameters of AG,AH and AS,as well as surface SEM and EDS images were used to investigate the removal of strontium ions from stimulated radioactive wastewater using the previously prepared hybrid membranes as efficient adsorbents.The study of kinetic model confirmed that the adsorption of strontium ions on these hybrid membranes followed the Lagergren pseudo-second order model.Moreover,it was proved that the adsorption of strontium ions on these samples was solely controlled by intraparticle diffusion.The negative values of AG and the positive values of AH indicated that the adsorption of strontium ions on samples A-D is a spontaneous and endothermic process in nature.Furthermore,surface SEM and DES images give significant evidence to confirm the existence of strontium ions on the surface of the adsorbed samples.These findings demonstrate that these hybrid membranes are promising adsorbents for the removal of strontium ions from aqueous solution and can be potentially applied in the adsorptive separation of radionuclides from the radioactive wastewater.展开更多
China clay was employed as an adsorbent for the removal of Mg 2+ from water at pH 7.0 within the temperature range of 303～328 K. The linearity of the plots indicated Langmuir type isotherms. The reaction was ex...China clay was employed as an adsorbent for the removal of Mg 2+ from water at pH 7.0 within the temperature range of 303～328 K. The linearity of the plots indicated Langmuir type isotherms. The reaction was exothermic. A maximum removal of 35% was obtained at 0.50 mmol L -1 metal concentration and a pH of 7.0 at 303 K. The H + rel /Mg 2+ ads ratio changed from a fractional value to 2.5. Strong chemical bondings took place between oxygen atom of the surface and Mg 2+ , resulting in a surface complex species. Temperature had a significant effect on H + rel , and the stability constants also increased with increasing temperature.展开更多
文摘Stability of Defibrase in various pH buffer solutions was investigated. Enzyme-linked immuno-sorbent assay (ELISA) and coagulating time method were used to assess antigenic stability and coagulating stability, respectively. The change of antigenic activities and coagulating activities of Defibrase in the same buffer solutions (pH 6, 7 and 8, with the exception of pH 3.6) showed similar tendency to decline with the time. Concentrated Defi-brase was relatively stable at neutral pH 6~7, more than 95% of its initial activities (100BUmL-1) was kept after a 10-day storage at 40 oC, whereas in pH 3.6 and pH 9 buffer solutions, diluted Defibrase was very labile. Addition of Triton X-100 or bovine serum albumin could effectively prevent loss of Defibrase by minimizing adsorption of De-fibrase to plastic surface (P<0.005). Concentration of Defibrase could also affect its stability in aqueous solutions.
基金Supported by the National Natural Science Foundation of China(21376059)the Priority Construction Discipline of Education Department of Anhui Provincethe Key Discipline of Hefei University(2014xk01)
文摘The removal of radionuclide from radioactive wastewater has captured much attention.Strontium-90 is one of the major radionuclides.To develop a new type of adsorbents to remove strontium ions from the radioactive wastewater,in this study,novel hybrid membranes were prepared and characterized.The adsorption kinetics,thermodynamic parameters of AG,AH and AS,as well as surface SEM and EDS images were used to investigate the removal of strontium ions from stimulated radioactive wastewater using the previously prepared hybrid membranes as efficient adsorbents.The study of kinetic model confirmed that the adsorption of strontium ions on these hybrid membranes followed the Lagergren pseudo-second order model.Moreover,it was proved that the adsorption of strontium ions on these samples was solely controlled by intraparticle diffusion.The negative values of AG and the positive values of AH indicated that the adsorption of strontium ions on samples A-D is a spontaneous and endothermic process in nature.Furthermore,surface SEM and DES images give significant evidence to confirm the existence of strontium ions on the surface of the adsorbed samples.These findings demonstrate that these hybrid membranes are promising adsorbents for the removal of strontium ions from aqueous solution and can be potentially applied in the adsorptive separation of radionuclides from the radioactive wastewater.
文摘China clay was employed as an adsorbent for the removal of Mg 2+ from water at pH 7.0 within the temperature range of 303～328 K. The linearity of the plots indicated Langmuir type isotherms. The reaction was exothermic. A maximum removal of 35% was obtained at 0.50 mmol L -1 metal concentration and a pH of 7.0 at 303 K. The H + rel /Mg 2+ ads ratio changed from a fractional value to 2.5. Strong chemical bondings took place between oxygen atom of the surface and Mg 2+ , resulting in a surface complex species. Temperature had a significant effect on H + rel , and the stability constants also increased with increasing temperature.
