Solvent extraction based on ionic liquids is generally considered to be an environmentally benign and effective technology for gold(Ⅰ)recovery.The aim of this work is to study gold(Ⅰ)extraction from aurocyanide solu...Solvent extraction based on ionic liquids is generally considered to be an environmentally benign and effective technology for gold(Ⅰ)recovery.The aim of this work is to study gold(Ⅰ)extraction from aurocyanide solution using fluorine-free ionic liquids[A336][SCN],[A336][MTBA]and[A336][Mal].Various factors that affect gold(Ⅰ)extraction(including concentration of ionic liquids,equilibrium pH,concentration of the modifier tributyl phosphate(TBP),reaction time and initial concentration of gold in an aqueous solution)were studied and optimized.The results indicate that the three Aliquat336-based ionic liquids all exhibit excellent behaviors for gold(Ⅰ)extraction.More than 99.8%of gold(Ⅰ)can be extracted from the aqueous phase into the ionic liquid phase.The gold-loaded ionic liquids were characterized using infrared spectroscopy and mass spectrometry to study the extraction mechanism of gold(Ⅰ).The results revealed that extraction of gold(Ⅰ)into the ionic liquid phase was based on an exchange reaction between the anion Au(CN)2-in aqueous solution and the anion SCN-in ionic liquid[A336][SCN].The logarithmic relationship between distribution coefficient and TBP concentration indicates that two TBP molecules are involved in the formation of the extracted complex.The extracted complex was determined to be A336^(+)·Au(CN)_(2)^(-)·2 TBP.In addition,the gold(Ⅰ)-loaded ionic liquids can be efficiently stripped using NH4 SCN,2-methylthiobenzoic acid and methyl maltol.The results establish that Aliquat 336-based ionic liquids have potential application prospects in gold(Ⅰ)recovery from cyanide solutions.展开更多
Background：High cost of imported pacemakers is a main obstacle for Chinese patients suffering from bradyarrhythmia,and a domestically developed pacemaker will help lower the burden.This study aimed to evaluate the sa...Background：High cost of imported pacemakers is a main obstacle for Chinese patients suffering from bradyarrhythmia,and a domestically developed pacemaker will help lower the burden.This study aimed to evaluate the safety and efficacy ofQinming8631 DR （Qinming Medical,Baoji,China）,the first domestically developed dual-chamber pacemaker of China,compared with a commercially available pacemaker Talos DR （Biotronik,Berlin,Germany） in Chinese patients.Methods：A prospective randomized trial was conducted at 14 centers in China.Participants were randomized into trial （Qinming8631 DR） and control （Talos DR） groups.Parameters of the pacing systems were collected immediately after device implantation and during follow-ups.The effective pacing rate at 6-month follow-up was recorded as the primary end point.Electrical properties,magnet response,single-and double-pole polarity conversion,rate response function,and adverse events of the pacing system were analyzed.The Cochran-Mantel-Haenszel Chi-square test,paired t-test,and Wilcoxon signed-rank test were used for measuring primary qualitative outcomes and comparing normally and abnormally distributed measurement data.Results：A total of 225 patients with a diagnosis ofbradyarrhythmia and eligible for this study were randomly enrolled into the trial （n =113） and control （n =112） groups.They underwent successful pacemaker implantation with acceptable postoperative pacing threshold and sensitivity.Effective pacing rates of trial and control groups were comparable both in the full analysis set and the per protocol set （81.4% vs.79.5%,P =0.712 and 95.4% vs.89.5%,P =0.143,respectively）.In both data sets,noninferiority of the trial group was above the predefined noninferiority limit（-9.5%）.Conclusions：This study established the noninferiority ofQinming8631 DR to Talos DR.The safety and efficacy ofQinming8631 DR pacemaker were comparable to those of Talos DR in treating patients with cardiac bradyarrhythmia.展开更多
基金the National Natural Science Foundation of China(No.51464044)the Natural Science Foundation of Yunnan Province(No.2018FB014)the Free Exploration Fund for Academician of Yunnan Province(No.2019HA005)。
文摘Solvent extraction based on ionic liquids is generally considered to be an environmentally benign and effective technology for gold(Ⅰ)recovery.The aim of this work is to study gold(Ⅰ)extraction from aurocyanide solution using fluorine-free ionic liquids[A336][SCN],[A336][MTBA]and[A336][Mal].Various factors that affect gold(Ⅰ)extraction(including concentration of ionic liquids,equilibrium pH,concentration of the modifier tributyl phosphate(TBP),reaction time and initial concentration of gold in an aqueous solution)were studied and optimized.The results indicate that the three Aliquat336-based ionic liquids all exhibit excellent behaviors for gold(Ⅰ)extraction.More than 99.8%of gold(Ⅰ)can be extracted from the aqueous phase into the ionic liquid phase.The gold-loaded ionic liquids were characterized using infrared spectroscopy and mass spectrometry to study the extraction mechanism of gold(Ⅰ).The results revealed that extraction of gold(Ⅰ)into the ionic liquid phase was based on an exchange reaction between the anion Au(CN)2-in aqueous solution and the anion SCN-in ionic liquid[A336][SCN].The logarithmic relationship between distribution coefficient and TBP concentration indicates that two TBP molecules are involved in the formation of the extracted complex.The extracted complex was determined to be A336^(+)·Au(CN)_(2)^(-)·2 TBP.In addition,the gold(Ⅰ)-loaded ionic liquids can be efficiently stripped using NH4 SCN,2-methylthiobenzoic acid and methyl maltol.The results establish that Aliquat 336-based ionic liquids have potential application prospects in gold(Ⅰ)recovery from cyanide solutions.
文摘Background：High cost of imported pacemakers is a main obstacle for Chinese patients suffering from bradyarrhythmia,and a domestically developed pacemaker will help lower the burden.This study aimed to evaluate the safety and efficacy ofQinming8631 DR （Qinming Medical,Baoji,China）,the first domestically developed dual-chamber pacemaker of China,compared with a commercially available pacemaker Talos DR （Biotronik,Berlin,Germany） in Chinese patients.Methods：A prospective randomized trial was conducted at 14 centers in China.Participants were randomized into trial （Qinming8631 DR） and control （Talos DR） groups.Parameters of the pacing systems were collected immediately after device implantation and during follow-ups.The effective pacing rate at 6-month follow-up was recorded as the primary end point.Electrical properties,magnet response,single-and double-pole polarity conversion,rate response function,and adverse events of the pacing system were analyzed.The Cochran-Mantel-Haenszel Chi-square test,paired t-test,and Wilcoxon signed-rank test were used for measuring primary qualitative outcomes and comparing normally and abnormally distributed measurement data.Results：A total of 225 patients with a diagnosis ofbradyarrhythmia and eligible for this study were randomly enrolled into the trial （n =113） and control （n =112） groups.They underwent successful pacemaker implantation with acceptable postoperative pacing threshold and sensitivity.Effective pacing rates of trial and control groups were comparable both in the full analysis set and the per protocol set （81.4% vs.79.5%,P =0.712 and 95.4% vs.89.5%,P =0.143,respectively）.In both data sets,noninferiority of the trial group was above the predefined noninferiority limit（-9.5%）.Conclusions：This study established the noninferiority ofQinming8631 DR to Talos DR.The safety and efficacy ofQinming8631 DR pacemaker were comparable to those of Talos DR in treating patients with cardiac bradyarrhythmia.
