Ordered macroporous materials with rapid mass transport and enhanced active site accessibility are essential for achieving improved catalytic activity.In this study,boron phosphate crystals with a three-dimensionally ...Ordered macroporous materials with rapid mass transport and enhanced active site accessibility are essential for achieving improved catalytic activity.In this study,boron phosphate crystals with a three-dimensionally interconnected ordered macroporous structure and a robust framework were fabricated and used as stable and selective catalysts in the oxidative dehydrogenation(ODH)of propane.Due to the improved mass diffusion and higher number of exposed active sites in the ordered macroporous structure,the catalyst exhibited a remarkable olefin productivity of^16 golefin gcat^-1 h^-1,which is up to 2–100 times higher than that of ODH catalysts reported to date.The selectivity for olefins was 91.5%(propene:82.5%,ethene:9.0%)at 515℃,with a propane conversion of 14.3%.At the same time,the selectivity for the unwanted deep-oxidized CO2 product remained less than 1.0%.The tri-coordinated surface boron species were identified as the active catalytic sites for the ODH of propane.This study provides a route for preparing a new type of metal-free catalyst with stable structure against oxidation and remarkable catalytic activity,which may represent a potential candidate to promote the industrialization of the ODH process.展开更多
Objective To investigate the levels of cardiovascular disease risk factors and their relations to clinical phenotype associated with coronary artery disease(CAD).Methods The subjects were recruited from five independe...Objective To investigate the levels of cardiovascular disease risk factors and their relations to clinical phenotype associated with coronary artery disease(CAD).Methods The subjects were recruited from five independent cardiovascular centers.Coronary angiography was employed to define the CAD with stenosis in each major vessel ≥70% and control with stenosis <10% in every lesion.The classic risk factors including family history,body mass index,smoking habits,hypertension,diabetes mellitus,and serum lipid levels were surveyed according to established criteria.Associations between risk levels and clinical phenotypes were assessed by case control and correlation analysis.Results A total of 762 individuals were collected,including 481 men and 281 women,aged from 17 to 81(mean 60±10) years.The patients with CAD accounted for 55.5% of all participants,and controls 44.5%,respectively.Compared with the pattern in published data,our study showed that mean serum high density lipoprotein cholesterol(HDL-C) level was significantly lower(P<0.001) and triglycerides was significantly higher(P<0.001),while total cholesterol(TC) and low density lipoprotein cholesterol levels were comparative(both P>0.05).The prevalence of low HDL-C(<40 g/L) and hypertriglyceridemia(>150 g/L) were 27.2% and 41.4%,respectively.Mean serum levels of HDL-C and apolipoprotein A1 were significantly higher in female subjects than in male(P<0.001).Lower HDL-C functioned as an independent risk factor for CAD only in men(RR=2.8,95%CI:1.5-4.2,P<0.001),yet increased non-HDL cholesterol combined with diabetes mellitus and obesity seemed to play a key role in the development ofCAD in women.Similarity in risk association with CAD was found for hypertension and TC/HDL ratio in male and female subjects,while family history had no relationship with the presence of CAD.Conclusion It is remarkable that emphasis of intervention in future should be given on the prevalent low serum HDL-C and its strong risk correlation with the presence of CAD in male subjects of Chinese Han population.展开更多
In the process of microemulsion flooding,microemulsion phase state may be affected by the adsorption of core and the distribution of oil and water,and the upper phase,the middle phase or the lower phase microemulsion ...In the process of microemulsion flooding,microemulsion phase state may be affected by the adsorption of core and the distribution of oil and water,and the upper phase,the middle phase or the lower phase microemulsion will appear.Accurate description of microemulsion phase state and quantitative discrimination of equilibrium phase composition are of great theoretical value and research significance for the design of microemulsion flooding system and improving the recovery efficiency of microemulsion.Therefore,in this paper,microemulsion phase model is deeply studied.Aiming at the difficulty of solving the existing Hand model and the unknown parameters of the improved HLD-NAC model,we introduce the binodal curve range parameter D and the asymmetric migration degree parameter B,and establish a new phase behavior description method of the binodal curve,the two-phase plait point lines and the III-phase node line.Then the phase discrimination programming of microemulsion was carried out,and the change laws of phase number,phase type and mass fraction of equilibrium phases of any microemulsion system under different salinity were revealed.The results show that the simulation results of microemulsions accord with the salinity scanning law,and can accurately identify the complex microemulsion phase states.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
文摘Ordered macroporous materials with rapid mass transport and enhanced active site accessibility are essential for achieving improved catalytic activity.In this study,boron phosphate crystals with a three-dimensionally interconnected ordered macroporous structure and a robust framework were fabricated and used as stable and selective catalysts in the oxidative dehydrogenation(ODH)of propane.Due to the improved mass diffusion and higher number of exposed active sites in the ordered macroporous structure,the catalyst exhibited a remarkable olefin productivity of^16 golefin gcat^-1 h^-1,which is up to 2–100 times higher than that of ODH catalysts reported to date.The selectivity for olefins was 91.5%(propene:82.5%,ethene:9.0%)at 515℃,with a propane conversion of 14.3%.At the same time,the selectivity for the unwanted deep-oxidized CO2 product remained less than 1.0%.The tri-coordinated surface boron species were identified as the active catalytic sites for the ODH of propane.This study provides a route for preparing a new type of metal-free catalyst with stable structure against oxidation and remarkable catalytic activity,which may represent a potential candidate to promote the industrialization of the ODH process.
基金Supported by a grant from Desert Foundation (2003),Salt Lake City,USA
文摘Objective To investigate the levels of cardiovascular disease risk factors and their relations to clinical phenotype associated with coronary artery disease(CAD).Methods The subjects were recruited from five independent cardiovascular centers.Coronary angiography was employed to define the CAD with stenosis in each major vessel ≥70% and control with stenosis <10% in every lesion.The classic risk factors including family history,body mass index,smoking habits,hypertension,diabetes mellitus,and serum lipid levels were surveyed according to established criteria.Associations between risk levels and clinical phenotypes were assessed by case control and correlation analysis.Results A total of 762 individuals were collected,including 481 men and 281 women,aged from 17 to 81(mean 60±10) years.The patients with CAD accounted for 55.5% of all participants,and controls 44.5%,respectively.Compared with the pattern in published data,our study showed that mean serum high density lipoprotein cholesterol(HDL-C) level was significantly lower(P<0.001) and triglycerides was significantly higher(P<0.001),while total cholesterol(TC) and low density lipoprotein cholesterol levels were comparative(both P>0.05).The prevalence of low HDL-C(<40 g/L) and hypertriglyceridemia(>150 g/L) were 27.2% and 41.4%,respectively.Mean serum levels of HDL-C and apolipoprotein A1 were significantly higher in female subjects than in male(P<0.001).Lower HDL-C functioned as an independent risk factor for CAD only in men(RR=2.8,95%CI:1.5-4.2,P<0.001),yet increased non-HDL cholesterol combined with diabetes mellitus and obesity seemed to play a key role in the development ofCAD in women.Similarity in risk association with CAD was found for hypertension and TC/HDL ratio in male and female subjects,while family history had no relationship with the presence of CAD.Conclusion It is remarkable that emphasis of intervention in future should be given on the prevalent low serum HDL-C and its strong risk correlation with the presence of CAD in male subjects of Chinese Han population.
基金financially supported by Northeast Petroleum University Talent Introduction Scientific Research Start-Up Foundation Project“dynamic characterization and prediction method of phase behavior of microemulsion flooding”National Natural Science Foundation of China under grant No.12002083Nature Science Foundation of Heilongjiang Province(LH2020E013)
文摘In the process of microemulsion flooding,microemulsion phase state may be affected by the adsorption of core and the distribution of oil and water,and the upper phase,the middle phase or the lower phase microemulsion will appear.Accurate description of microemulsion phase state and quantitative discrimination of equilibrium phase composition are of great theoretical value and research significance for the design of microemulsion flooding system and improving the recovery efficiency of microemulsion.Therefore,in this paper,microemulsion phase model is deeply studied.Aiming at the difficulty of solving the existing Hand model and the unknown parameters of the improved HLD-NAC model,we introduce the binodal curve range parameter D and the asymmetric migration degree parameter B,and establish a new phase behavior description method of the binodal curve,the two-phase plait point lines and the III-phase node line.Then the phase discrimination programming of microemulsion was carried out,and the change laws of phase number,phase type and mass fraction of equilibrium phases of any microemulsion system under different salinity were revealed.The results show that the simulation results of microemulsions accord with the salinity scanning law,and can accurately identify the complex microemulsion phase states.
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.