Influence of surfactant on the permeability at different positions of a leaching column.

To solve the problems of poor permeability and low leaching rate in ore heap leaching, solid surface physical chemistry, seepage mechanics theory for porous media, CT scanning and SEM were used to carry out column leaching tests with a homemade segmented removable plexiglass column; the variation law for the permeability coefficients of each segment of the leaching column before and after leaching was analyzed. The experimental results showed that there was little difference in the permeability coefficient of ore at different heights before leaching. After leaching, the permeability coefficients were unevenly distributed along the column height, and the lowest value was located at the bottom of the leaching column. The addition of surfactant provided an obvious improvement in the permeability of the leaching column. The permeability coefficient at the bottom of the leaching column was 6% higher than that of the control group. At the same time, the addition of surfactant increased the leaching rate of ore by nearly 10%. A theoretical analysis showed that the surfactant improved the permeability of ore heaps mainly by preventing physical blockage by fine particles and inhibiting deposition of chemical products.

Associations of SUMO4 polymorphisms with tacrolimus concentrations in Chinese renal transplant recipients / 药学学报

The study aims to investigate the associations of SUMO4 polymorphisms with tacrolimus concentrations in Chinese renal transplant recipients. Blood samples and clinical data were collected from 132 renal transplant recipients with tacrolimus treatment. CYP3A5*3 genotypes were detected by PCR-RFLP, and SUMO4 (rs237024, rs237025) genotypes were detected by Sequenom® MassARRAY system. SUMO4 rs237024 and rs237025 genotypes were in complete linkage disequilibrium (D' = 1). The dose-adjusted concentration of tacrolimus in SUMO4 rs237024A-rs237025A (GA-GA +AA-AA) carriers was considerably higher than that in GG-GG carriers (P < 0.05). After stratification by CYP3A5*3 genotypes, SUMO4 rs237024A-rs237025A carriers (GA-GA+AA-AA) had a higher dose-adjusted tacrolimus concentration than that in GG carriers in CYP3A5 expresser (P < 0.05). The results illustrated that SUMO4 rs237024 and rs237025 polymorphisms were associated with tacrolimus concentrations, and the test of these genotypes may be useful for individualized medicine of tacrolimus.