RESUMO
Co3O4 has received much attention because of its excellent performance in activating peroxymonosulfate. However, the practical application of Co3O4 has been seriously restricted by the problems of agglomeration of Co3O4, difficult separation, easy loss, and poor recycling. In this study, the CMF/Co3O4 heterogeneous catalyst was prepared using the hydrothermal method. The crystal structure and morphology of CMF/Co3O4 were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Rhodamine B (RhB) degradation was employed as a model test for evaluating potassium peroxymonosulfate (PMS) activation. The degradation rate of RhB can reach 98% in the catalyst dosage of 35 mg·L-1, PMS concentration of 50 mg·L-1, pH of 7, and RhB initial concentration of 10 mg·L-1 after a 30 min reaction. The results showed that the degradation rate of RhB could be significantly improved by increasing the amount of CMF/Co3O4 heterogeneous catalyst and the mass concentration of PMS. The degradation rate of RhB can be inhibited by increasing the initial mass concentration of RhB and pH value. The process of degradation of RhB can be fitted by using the pseudo first-order kinetics model. The effect of temperature on the degradation rate of RhB conformed to the Arrhenius model, and the degradation process was a surface reaction-controlled process. The results of the free radical capture experiment showed that the sulfate radicals were the dominant active species for RhB degradation. After four cycles, the degradation rate of RhB still remained above 93% with CMF/Co3O4 catalyst.
RESUMO
OBJECTIVE: To explore the clinical features and disease spectrums for ANCA (anti-neutrophil cytoplasmic antibodies)-associated vasculitis (AAV) and to improve its cognition. METHODS: Clinical features of 190 cases of patients with AAV hospitalized from 1998 to 2008 were reviewed retrospectively. According to the result of ANCA test, the patients were divided into two groups, cytoplasmic ANCA (C-ANCA) positive and perinuclear ANCA (P-ANCA) positive. The authors compared the differences of disease spectrums, clinical manifestations and laboratory tests between two groups. The relative mortality factors were also analyzed. RESULTS: The authors studied 92 males and 98 females with an age range of 8 - 89 (59 +/- 18) years old. There were 156 cases aged 40 - 80 years old (82.1%) and 162 patients (85.3%) were of primary AAV including 146 cases of P-ANCA positive and 16 cases of C-ANCA positive. There were 28 patients with secondary AAV including 18 cases of connective tissue disease, 7 cases of propylthiouracil induction, 1 case each of idiopathic thrombocytopenic purpura, lung cancer and endometrial carcinoma. There were 25 cases of P-ANCA positive and 3 cases of C-ANCA positive in secondary AAV. There were 171 cases (90.0%) in P-ANCA group and 19 cases (10.0%) in C-ANCA group. The number of organ involvement was 2.53 in C-ANCA group and 1.92 in P-ANCA group. Gastrointestinal tract, joint, upper respiratory tract and ocular involvement was more in C-ANCA group than in P-ANCA group. Oral and auricular involvement was more in P-ANCA group than in C-ANCA group. The involvement difference was of statistic significance in upper respiratory tract, joint and eye (all P < 0.05). Renal and pulmonary involvement in P-ANCA group was similar to C-ANCA group. There were 3 mortality cases in C-ANCA group and 22 in P-ANCA group. Respiratory failure and multiple organ dysfunctions were relative mortality factors. CONCLUSIONS: AAV is observed in elders with multiple organ involvement. The number of organ involvement in C-ANCA group is more than that in P-ANCA group. P-ANCA positive patients are more than c-ANCA patients. The disease spectrum is different in these two groups. Secondary AAV is more in P-ANCA group than in C-ANCA group. Clinical manifestations, laboratory tests and type of ANCA are helpful for the diagnosis of AAV.
