For the purpose of obtaining small molecular and oxygen-containing aromatic compounds, taking a toluene-extracted coal pitch as the research object, the oxidation of coal-pitch by ozone (03) in formic acid was studi...For the purpose of obtaining small molecular and oxygen-containing aromatic compounds, taking a toluene-extracted coal pitch as the research object, the oxidation of coal-pitch by ozone (03) in formic acid was studied. The coal-pitch sample and the oxidized pitch residue were characterized by elementary analysis and Fourier transform infrared spectroscopy (FTIR), while the small molecular products were analyzed by a gas chromatography-mass spectrometer (GC-MS). The results show that the highest oxygen content of oxidized coal pitch had been acquired at a reaction temperature of 50℃C, an 03 flow rate of 6300 mg/h and a reaction time of 4 h. Quite a lot of hydroxyls and carbonyls were introduced into the structure of the oxidized coal-pitch, while the small molecules produced mainly involve nonpolar aro- matic compounds, aromatic anhydride and quinone compounds. It is speculated that the mechanism is direct electrophilic oxidation in which the molecules of 03 directly attack the aromatic ring at its carbon atoms with high electron density, and then generate hydroxyl or carbonyl until the aromatic ring cracks. This study shows that 03 can make the fused aromatic ring of coal-pitch become oxidized and depoly- merized, and hence the ozonization of coal-pitch can be a potential method for obtaining oxygen- containing aromatic compounds.展开更多
Objective To evaluate the effect of real-world practices for icodextrin peritoneal dialysis solution on patients with end-stage renal disease(ESRD)by Meta-analysis.Methods The PubMed and Embase databases were systemat...Objective To evaluate the effect of real-world practices for icodextrin peritoneal dialysis solution on patients with end-stage renal disease(ESRD)by Meta-analysis.Methods The PubMed and Embase databases were systematically searched for real-world research literature on icodextrin peritoneal dialysate in the treatment of ESRD patients,and RevMan5.4 statistical software was used for Meta-analysis.Results and Conclusion 12 studies with 114656 patients were included.Meta-analysis results showed that icodextrin peritoneal dialysis had good effects on mortality[RR=0.72,95%CI(0.62,0.83),P<0.001],congestive heart failure[RR=0.67,95%CI(0.52,0.87),P=0.003],and risk of new-onset diabetes[RR=0.65,95%CI(0.49,0.86),P=0.003],which was consistent with the Meta-analysis based on clinical trials.Meanwhile,there was no significant difference in PD technical failure rate[RR=0.67,95%CI(0.44,1.00),P=0.05],peritonitis[RR=1.02,95%CI(0.99,1.05),P=0.14],cardiovascular and cerebrovascular diseases[RR=0.79,95%CI(0.59,1.05),P=0.10],coronary artery disease[RR=0.99,95%CI(0.92,1.07),P=0.80],stroke[RR=0.86,95%CI(0.66,1.10),P=0.23],and atrial fibrillation[RR=0.73,95%CI(0.37,1.44),P=0.36].However,it might increase the risk of hypertension[RR=1.05,95%CI(1.03,1.07),P<0.001].Therefore,icodextrin can effectively reduce the risk of mortality,congestive heart failure,and new-onset diabetes,which is beneficial to ESRD patients.展开更多
基金financially supported by the Key Project of Science and Technology of Universities of Henan Province (No.14A530003)the Key Project of Science and Technology of Henan Province (No.152102310090)
文摘For the purpose of obtaining small molecular and oxygen-containing aromatic compounds, taking a toluene-extracted coal pitch as the research object, the oxidation of coal-pitch by ozone (03) in formic acid was studied. The coal-pitch sample and the oxidized pitch residue were characterized by elementary analysis and Fourier transform infrared spectroscopy (FTIR), while the small molecular products were analyzed by a gas chromatography-mass spectrometer (GC-MS). The results show that the highest oxygen content of oxidized coal pitch had been acquired at a reaction temperature of 50℃C, an 03 flow rate of 6300 mg/h and a reaction time of 4 h. Quite a lot of hydroxyls and carbonyls were introduced into the structure of the oxidized coal-pitch, while the small molecules produced mainly involve nonpolar aro- matic compounds, aromatic anhydride and quinone compounds. It is speculated that the mechanism is direct electrophilic oxidation in which the molecules of 03 directly attack the aromatic ring at its carbon atoms with high electron density, and then generate hydroxyl or carbonyl until the aromatic ring cracks. This study shows that 03 can make the fused aromatic ring of coal-pitch become oxidized and depoly- merized, and hence the ozonization of coal-pitch can be a potential method for obtaining oxygen- containing aromatic compounds.
文摘Objective To evaluate the effect of real-world practices for icodextrin peritoneal dialysis solution on patients with end-stage renal disease(ESRD)by Meta-analysis.Methods The PubMed and Embase databases were systematically searched for real-world research literature on icodextrin peritoneal dialysate in the treatment of ESRD patients,and RevMan5.4 statistical software was used for Meta-analysis.Results and Conclusion 12 studies with 114656 patients were included.Meta-analysis results showed that icodextrin peritoneal dialysis had good effects on mortality[RR=0.72,95%CI(0.62,0.83),P<0.001],congestive heart failure[RR=0.67,95%CI(0.52,0.87),P=0.003],and risk of new-onset diabetes[RR=0.65,95%CI(0.49,0.86),P=0.003],which was consistent with the Meta-analysis based on clinical trials.Meanwhile,there was no significant difference in PD technical failure rate[RR=0.67,95%CI(0.44,1.00),P=0.05],peritonitis[RR=1.02,95%CI(0.99,1.05),P=0.14],cardiovascular and cerebrovascular diseases[RR=0.79,95%CI(0.59,1.05),P=0.10],coronary artery disease[RR=0.99,95%CI(0.92,1.07),P=0.80],stroke[RR=0.86,95%CI(0.66,1.10),P=0.23],and atrial fibrillation[RR=0.73,95%CI(0.37,1.44),P=0.36].However,it might increase the risk of hypertension[RR=1.05,95%CI(1.03,1.07),P<0.001].Therefore,icodextrin can effectively reduce the risk of mortality,congestive heart failure,and new-onset diabetes,which is beneficial to ESRD patients.