Cultivation of aerobic granular sludge for pentachlorophenol(PCP) degradation under microaerobic condition(DO concentration was controlled at 0.2—0.7 mg/L) was studied in this paper. Anaerobic granules were selected ...Cultivation of aerobic granular sludge for pentachlorophenol(PCP) degradation under microaerobic condition(DO concentration was controlled at 0.2—0.7 mg/L) was studied in this paper. Anaerobic granules were selected as inoculum. The changes of appearance were observed and the variations of SVI, VSS/TSS, PN/PS and the size of sludge were measured during cultivating. The capabilities for degradation of PCP, AOX and COD_ Cr were also studied. Observations on mature granules were carried out by scanning electron microscope, and the results indicated bacillus was dominant on the surface of granules while in the inner of granules both bacillus and coccus were the dominant microorganisms. K, Na, Fe, Ca, Mg, Ni, Co, Mn, Cu and Zn were detected in the granules by element analysis.展开更多
The present paper covers the synthesis and the characterization of ligand 2-decyl-3,6,9-tris(carboxymethyl)-3,6,9-triazaundecan-1,11-dioic acid,H_5L,and its Gd(Ⅲ) chelate. The protonation constants for H_5L(lg K H_...The present paper covers the synthesis and the characterization of ligand 2-decyl-3,6,9-tris(carboxymethyl)-3,6,9-triazaundecan-1,11-dioic acid,H_5L,and its Gd(Ⅲ) chelate. The protonation constants for H_5L(lg K H_ i =10.90,8.50,4.55,2.92,2.20) and the stability constant for GdL 2- (lg K _ GdL 2- =22.80) were determined by means of potentiometric titration. They are similar to the corresponding values of DTPA and Gd-DTPA,respectively. The results obtained show that the basicity of the ligand and the stability constant of its Gd(Ⅲ) chelate are not obviously altered after the introduction of a linear chain decyl group into the terminal acetic acid residue of DTPA. The Gd(Ⅲ) chelate may be a potential contrast agent with liver-specificity for magnetic resonance imaging(MRI).展开更多
基金The Guangdong Natural Science Foundation(No. 31430) State Key Laboratory of Pulp and Paper Making Engineering, South China University of Technology(No. 200335) and the Laboratory of Cellulose and Lignocellulosics Chemistry, Chinese Academy of Sciences(No.K 147)
文摘Cultivation of aerobic granular sludge for pentachlorophenol(PCP) degradation under microaerobic condition(DO concentration was controlled at 0.2—0.7 mg/L) was studied in this paper. Anaerobic granules were selected as inoculum. The changes of appearance were observed and the variations of SVI, VSS/TSS, PN/PS and the size of sludge were measured during cultivating. The capabilities for degradation of PCP, AOX and COD_ Cr were also studied. Observations on mature granules were carried out by scanning electron microscope, and the results indicated bacillus was dominant on the surface of granules while in the inner of granules both bacillus and coccus were the dominant microorganisms. K, Na, Fe, Ca, Mg, Ni, Co, Mn, Cu and Zn were detected in the granules by element analysis.
文摘The present paper covers the synthesis and the characterization of ligand 2-decyl-3,6,9-tris(carboxymethyl)-3,6,9-triazaundecan-1,11-dioic acid,H_5L,and its Gd(Ⅲ) chelate. The protonation constants for H_5L(lg K H_ i =10.90,8.50,4.55,2.92,2.20) and the stability constant for GdL 2- (lg K _ GdL 2- =22.80) were determined by means of potentiometric titration. They are similar to the corresponding values of DTPA and Gd-DTPA,respectively. The results obtained show that the basicity of the ligand and the stability constant of its Gd(Ⅲ) chelate are not obviously altered after the introduction of a linear chain decyl group into the terminal acetic acid residue of DTPA. The Gd(Ⅲ) chelate may be a potential contrast agent with liver-specificity for magnetic resonance imaging(MRI).
