Degradation efficiencies of 2,4,6-TCP by Fe0-based advanced oxidation processes (AOPs) with common peroxides.

Degradation of 2,4,6-trichlorophenol (2,4,6-TCP) by zero-valent iron (ZVI) activating three common peroxides (peroxymonosulfate (PMS), hydrogen peroxide (H2O2), and peroxydisulfate (PS)) was investigated. The effects of ZVI dosage, peroxides concentration, initial pH, and Cl- concentration were examined. The 2,4,6-TCP degradation efficiencies by Fe0/peroxides (PMS, H2O2, PS) were compared. Results showed that the order for degradation efficiency was H2O2≥PMS>PS. The degradation efficiency of 2,4,6-TCP in ZVI/peroxides systems were optimal at c(Ox) = 1 mmol•L-1; c(Fe0) = 0.1 g/L; initial pH = 3.2. Additionally, pH had a vital effect on 2,4,6-TCP degradation. At pH<3.2, ferrous play a vital role in all reaction, and accelerate the reaction rate rapidly. The existence of NaCl showed different results in the four systems. Chloride had little effect on 2,4,6-TCP degradation when chloride concentration at 5 mM, whereas the presence of 300 mM chloride significantly accelerated the degradation of 2,4,6-TCP from 72.7% to 95.2% in ZVI-PMS system. Notably, the other three systems showed opposite results. In contrast, the AOX (Absorbable Organic Halogen) values were highest in ZVI-PMS-Cl- system, due to the formation of lots of refractory chlorinated phenols as identified by GC-MS. These findings are good for choosing the most suitable technology for chlorophenol wastewater treatment.

[Construction and identification of small interfering RNA expression plasmid targeting Sox9 and the function to cell growth and apoptosis of human chondrosarcoma cells HTB94].

OBJECTIVES: To construct small interfering (siRNA) Sox9 expression plasmid and transfer it into human chondrosarcoma cells HTB-94, and to check the mRNA and protein expression of Sox9 and cell growth and apoptosis of HTB-94 human chondrosarcoma cells. METHODS: siRNA(Sox9) expression plasmid was designed and synthesized. And it was transferred into HTB-94 human chondrosarcoma cells. Then the expression of the mRNA and protein of Sox9, cell growth and apoptosis in transferred HTB-94 human chondrosarcoma cells were checked. RESULTS: The recombinant plasmid was confirmed by enzyme digestion analysis and DNA sequencing. The expression of the mRNA and protein expression of Sox9 in transferred HTB-94 were significantly reduced. The cell growth of HTB-94 was inhibited, and the apoptosis of HTB-94 was remarkably increased. CONCLUSION: siRNA (Sox9) expression plasmid could be transferred into HTB-94 human chondrosarcoma cells. And it can reduce the mRNA and protein expression of the HTB-94, inhibit the cell growth and cause the apoptosis of the tumor cells.