The applications of natural polymeric flocculants due to their green feature has been recently received much more attention. In this work, the combined usages of a cationic starch-based coagulant and polyaluminum chlo...The applications of natural polymeric flocculants due to their green feature has been recently received much more attention. In this work, the combined usages of a cationic starch-based coagulant and polyaluminum chloride(PACl) were extensively evaluated for various addition sequences in the coagulation of both raw(surface water from the Jiuxiang River) and synthetic turbid water(two kaolin suspensions with different initial turbidities).Two typical cationic starch-based coagulants with different structures(St-G and St-E) were tried. In comparison to St-G, St-E and PACl used individually as well as St-G and St-E dosed after PACl, the combination of the starch-based coagulants fed before PACl showed higher turbidity removal efficiency, which featured not only less optimal doses of both inorganic and organic coagulants but also lower residual turbidity. On the basis of a detailed analysis of the particle size and its distribution in solution supernatants before and after coagulation by two starch-based coagulants and PACl, polymeric coagulants preferentially coagulate the small-sized colloids due to their distinct long-chain structures, but PACl preferentially coagulates the medium-sized ones. Thus, the medium-sized particles that were previously formed by the starch-based coagulants would be collectively and effectively removed by the subsequent addition of PACl. The addition sequence of the inorganic and organic coagulants in their combined usage is an important factor for improvement of the turbidity removal efficiency in practice.展开更多
Comparative pilot tests were conducted to investigate the coagulation-aid effects of the combined preoxidation by potassium permanganate composites （PPC） with chlorine and preozonation. And the synergistie mechanism...Comparative pilot tests were conducted to investigate the coagulation-aid effects of the combined preoxidation by potassium permanganate composites （PPC） with chlorine and preozonation. And the synergistie mechanism of combined preoxidation was discussed. Results showed that 1.0 mg/L PPC with 2. 0 mg/L chlorine could further improve the quality of treated water, as indicated by residual turbidity, TOC and algae. The enhanced efficiency could be explained by the synergistic effect of the preoxidants themselves, or the effect of chlorine and the intermediate such as hydrous manganese dioxide, which was generated by potassium permanga- nate, the main ingredient of PPC.展开更多
目的探讨全麻、腰硬联合麻醉及硬膜外麻醉对单侧下肢骨关节手术围手术期凝血功能的影响。方法选择台州市中心医院2012年1月—2016年12月单侧下肢骨关节手术患者180例,根据随机数字法分为全麻组、腰硬联合麻醉组和硬膜外麻醉组,每组60例...目的探讨全麻、腰硬联合麻醉及硬膜外麻醉对单侧下肢骨关节手术围手术期凝血功能的影响。方法选择台州市中心医院2012年1月—2016年12月单侧下肢骨关节手术患者180例,根据随机数字法分为全麻组、腰硬联合麻醉组和硬膜外麻醉组,每组60例。术后6 h、24 h、48 h对患者进行VAS评分;麻醉前、麻醉后6 h、术后24 h测定凝血功能,记录围手术期血栓性并发症的发生情况。结果腰硬联合麻醉组和硬膜外麻醉组术后6 h、术后24 h和术后48 h VAS评分低于全麻组(P<0.05),腰硬联合麻醉组术后6 h、术后24 h和术后48 h VAS评分低于硬膜外麻醉组(P<0.05)。全麻组、腰硬联合麻醉组、硬膜外麻醉组麻醉后6 h和术后24 h PT值和TT值均高于麻醉前(P<0.05),麻醉后6 h APTT值均高于麻醉前(P<0.05),术后24 h APTT值和麻醉前比较差异无统计学意义(P>0.05),麻醉后6 h和术后24 h Fbg值均低于麻醉前(P<0.05)。腰硬联合麻醉组和硬膜外麻醉组围手术期血栓性并发症的发生率低于全麻组(P<0.05)。结论腰硬联合麻醉和硬膜外麻醉对单侧下肢骨关节手术的镇痛效果好,能够改善围手术期血液高凝状态,降低围手术期血栓性并发症的发生率,其中腰硬联合麻醉效果更佳。展开更多
基金supported by the National Natural Science Foundation of China(Nos.51778279 and 51438008)
文摘The applications of natural polymeric flocculants due to their green feature has been recently received much more attention. In this work, the combined usages of a cationic starch-based coagulant and polyaluminum chloride(PACl) were extensively evaluated for various addition sequences in the coagulation of both raw(surface water from the Jiuxiang River) and synthetic turbid water(two kaolin suspensions with different initial turbidities).Two typical cationic starch-based coagulants with different structures(St-G and St-E) were tried. In comparison to St-G, St-E and PACl used individually as well as St-G and St-E dosed after PACl, the combination of the starch-based coagulants fed before PACl showed higher turbidity removal efficiency, which featured not only less optimal doses of both inorganic and organic coagulants but also lower residual turbidity. On the basis of a detailed analysis of the particle size and its distribution in solution supernatants before and after coagulation by two starch-based coagulants and PACl, polymeric coagulants preferentially coagulate the small-sized colloids due to their distinct long-chain structures, but PACl preferentially coagulates the medium-sized ones. Thus, the medium-sized particles that were previously formed by the starch-based coagulants would be collectively and effectively removed by the subsequent addition of PACl. The addition sequence of the inorganic and organic coagulants in their combined usage is an important factor for improvement of the turbidity removal efficiency in practice.
基金Sponsored by the Development Program for Outstanding Young Teachers in Harbin Institute of Technology (Grant No.HITQNJS.2008.042)State KeyLab of Urban Water Resource and Environment(Grant No. HIT.ES200803)Harbin Science and Technology Development Program for Young Innovative Scholars(Grant No.2009RFQXS010)
文摘Comparative pilot tests were conducted to investigate the coagulation-aid effects of the combined preoxidation by potassium permanganate composites （PPC） with chlorine and preozonation. And the synergistie mechanism of combined preoxidation was discussed. Results showed that 1.0 mg/L PPC with 2. 0 mg/L chlorine could further improve the quality of treated water, as indicated by residual turbidity, TOC and algae. The enhanced efficiency could be explained by the synergistic effect of the preoxidants themselves, or the effect of chlorine and the intermediate such as hydrous manganese dioxide, which was generated by potassium permanga- nate, the main ingredient of PPC.
文摘目的探讨全麻、腰硬联合麻醉及硬膜外麻醉对单侧下肢骨关节手术围手术期凝血功能的影响。方法选择台州市中心医院2012年1月—2016年12月单侧下肢骨关节手术患者180例,根据随机数字法分为全麻组、腰硬联合麻醉组和硬膜外麻醉组,每组60例。术后6 h、24 h、48 h对患者进行VAS评分;麻醉前、麻醉后6 h、术后24 h测定凝血功能,记录围手术期血栓性并发症的发生情况。结果腰硬联合麻醉组和硬膜外麻醉组术后6 h、术后24 h和术后48 h VAS评分低于全麻组(P<0.05),腰硬联合麻醉组术后6 h、术后24 h和术后48 h VAS评分低于硬膜外麻醉组(P<0.05)。全麻组、腰硬联合麻醉组、硬膜外麻醉组麻醉后6 h和术后24 h PT值和TT值均高于麻醉前(P<0.05),麻醉后6 h APTT值均高于麻醉前(P<0.05),术后24 h APTT值和麻醉前比较差异无统计学意义(P>0.05),麻醉后6 h和术后24 h Fbg值均低于麻醉前(P<0.05)。腰硬联合麻醉组和硬膜外麻醉组围手术期血栓性并发症的发生率低于全麻组(P<0.05)。结论腰硬联合麻醉和硬膜外麻醉对单侧下肢骨关节手术的镇痛效果好,能够改善围手术期血液高凝状态,降低围手术期血栓性并发症的发生率,其中腰硬联合麻醉效果更佳。
