Bauxite residue is a highly alkaline material generated from the production of alumina in which bauxite is dissolved in caustic soda.Approximately 4.4 billion tons of bauxite residues are either stockpiled or landfill...Bauxite residue is a highly alkaline material generated from the production of alumina in which bauxite is dissolved in caustic soda.Approximately 4.4 billion tons of bauxite residues are either stockpiled or landfilled,creating environmental risks either from the generation of dust or migration of filtrates.High alkalinity is the critical factor restricting complete utilization of bauxite residues,whilst the application of alkaline regulation agents is costly and difficult to apply widely.For now,current industrial wastes,such as waste acid,ammonia nitrogen wastewater,waste gypsum and biomass,have become major problems restricting the development of the social economy.Regulation of bauxite residues alkalinity by industrial waste was proposed to achieve‘waste control by waste’with good economic and ecological benefits.This review will focus on the origin and transformation of alkalinity in bauxite residues using typical industrial waste.It will propose key research directions with an emphasis on alkaline regulation by industrial waste,whilst also providing a scientific reference point for their potential use as amendments to enhance soil formation and establish vegetation on bauxite residue disposal areas(BRDAs)following large-scale disposal.展开更多
This study focused on leaching behavior of alkaline anion and sodium in bauxite residue through ammonium chloride treatment.The results showed that the pH of bauxite residue decreased from 10.49 to 8.93,total alkaline...This study focused on leaching behavior of alkaline anion and sodium in bauxite residue through ammonium chloride treatment.The results showed that the pH of bauxite residue decreased from 10.49 to 8.93,total alkaline anion(HCO3^-,CO3^2-,OH^-,AlO2^-)concentration reduced from 38.89 to 25.50 mmol/L,leaching rate of soluble sodium was 80.86%with ammonium chloride addition of 0.75%,liquid/solid(L/S)ratio of 3(mL/g),temperature of 30°C and reaction time of 18 h;L/S ratio was the main factor affecting the removal of alkaline anion and the leaching of sodium.Furthermore,ammonium chloride promoted the dissolution of diaspore and changed the micro/morphological characteristics with the increase of massive structure.The findings of this work will contribute to achieve soil-formation of bauxite residue.展开更多
Alkaline anions,include CO3^2–,HCO3^–,Al(OH)4^–,OH^–,continuously released from bauxite residue(BR),will cause a potential disastrous impact on surrounding environment.The composition variation of alkaline anions,...Alkaline anions,include CO3^2–,HCO3^–,Al(OH)4^–,OH^–,continuously released from bauxite residue(BR),will cause a potential disastrous impact on surrounding environment.The composition variation of alkaline anions,alkaline phase transformation pathway,and micro-morphological transition characteristics during the gypsum addition were investigated in an attempt to understand alkalinity stabilization behavior.Results demonstrated that alkaline anions stabilization degree in leachates can reach approximately 96.29%,whilst pH and alkalinity were reduced from 10.47 to 8.15,47.39 mmol/L to 2 mmol/L,respectively.During the alkalinity stabilization,chemical regulation behavior plays significant role in driving the co-precipitation reaction among the critical alkaline anions(CO3^2–,HCO3^–,Al(OH)4^–,OH^–),with calcium carbonate(CaCO3))being the most prevalent among the transformed alkaline phases.In addition,XRD and SEM-EDX analyses of the solid phase revealed that physical immobilization behavior would also influence the stability of soluble alkali and chemical bonded alkali due to released Ca^2+from gypsum which aggregated the clay particles and stabilized them into coarse particles with a blocky structure.These findings will be beneficial for effectively regulating strong alkalinity of BR.展开更多
[目的]探讨收肌管阻滞(adductor canal block,ACB)联合腘动脉与膝关节后囊间隙(interspace between the popliteal artery and capsule of the knee,IPACK)阻滞在全膝关节置换术(total knee arthroplasty,TKA)的镇痛效果。[方法]2020年...[目的]探讨收肌管阻滞(adductor canal block,ACB)联合腘动脉与膝关节后囊间隙(interspace between the popliteal artery and capsule of the knee,IPACK)阻滞在全膝关节置换术(total knee arthroplasty,TKA)的镇痛效果。[方法]2020年2月—2022年6月84例终末期膝骨性关节炎患者在静脉全麻下进行初次单侧TKA术,依据术前医患沟通结果,42例采用ACB、PACK联合I阻滞(联合组),另外42例采用单纯ACB阻滞(ACB组),比较两组围手术期临床与镇痛相关资料。[结果]两组手术时间、总不良反应、术中失血量差异无统计学意义(P>0.05),联合组术后恢复下地行走显著早于ACB组[(18.5±4.3)h vs(30.4±6.7)h,P<0.001],联合组术后8 h[(69.3±7.3)°vs(64.8±6.9)°,P=0.005]、术后24 h[(70.1±6.3)°vs(65.2±6.7)°,P=0.001]膝ROM显著大于ACB组。术后2~24 h两组的VAS评分均有所上升,但联合组术后各时间点均显著低于ACB组(P<0.05),联合组首次补救镇痛时间[(6.3±1.8)h vs(10.4±2.3)h,P<0.001]、镇痛泵按压次数[(3.0±0.5)次vs(5.7±0.7)次,P<0.001]、使用血管活性药物次数[(1.0±0.2)次vs(1.7±0.4)次,P<0.001]、额外镇痛药使用次数[(1.4±0.4)次vs(1.9±0.6)次,P<0.001]均显著低于ACB组。[结论]ACB联合IPACK阻滞能够降低TKA术后疼痛症状,提升膝关节活动度,缩短恢复下床时间。展开更多
Rosmarinic acid,a common ester extracted from Rosemary,Perilla frutescens,and Salvia miltiorrhiza Bunge,has been shown to have protective effects against various diseases.This is an investigation into whether rosmarin...Rosmarinic acid,a common ester extracted from Rosemary,Perilla frutescens,and Salvia miltiorrhiza Bunge,has been shown to have protective effects against various diseases.This is an investigation into whether rosmarinic acid can also affect the changes of white matter fibers and cognitive deficits caused by hypoxic injury.The right common carotid artery of 3-day-old rats was ligated for 2 hours.The rats were then prewarmed in a plastic container with holes in the lid,which was placed in 37°C water bath for 30 minutes.Afterwards,the rats were exposed to an atmosphere with 8% O2 and 92% N2 for 30 minutes to establish the perinatal hypoxia/ischemia injury models.The rat models were intraperitoneally injected with rosmarinic acid 20 mg/kg for 5 consecutive days.At 22 days after birth,rosmarinic acid was found to improve motor,anxiety,learning and spatial memory impairments induced by hypoxia/ischemia injury.Furthermore,rosmarinic acid promoted the proliferation of oligodendrocyte progenitor cells in the subventricular zone.After hypoxia/ischemia injury,rosmarinic acid reversed to some extent the downregulation of myelin basic protein and the loss of myelin sheath in the corpus callosum of white matter structure.Rosmarinic acid partially slowed down the expression of oligodendrocyte marker Olig2 and myelin basic protein and the increase of oligodendrocyte apoptosis marker inhibitors of DNA binding 2.These data indicate that rosmarinic acid ameliorated the cognitive dysfunction after perinatal hypoxia/ischemia injury by improving remyelination in corpus callosum.This study was approved by the Animal Experimental Ethics Committee of Xuzhou Medical University,China (approval No.20161636721) on September 16,2017.展开更多
A simulation method for measurement of the cross-section of the^(14)N(n,a)^(11)B reaction with gas and solid samples using a gridded ionization chamber(GIC)has been established.Using the simulation,the experimental sp...A simulation method for measurement of the cross-section of the^(14)N(n,a)^(11)B reaction with gas and solid samples using a gridded ionization chamber(GIC)has been established.Using the simulation,the experimental spectra of both^(14)N(n,a)^(11)B events and background from other reactions can be predicted,and the experimental scheme can be optimized.According to the simulation results,the optimal experimental parameters,including the pressure of the working gas and the compositions of the working gas and the sample,can be determined.In addition,the simulation results can be used to determine the valid event area and calculate the detection efficiency for valid events.A measurement of the cross-sections of the^(14)N(n,a)^(11)B reaction at E_(n)=4.25,4.50,4.75,5.00,5.25,and 5.50 MeV,based on the 4.5-MV Van de Graff accelerator at Peking University(PKU)using a GIC as the detector for the outgoing a particles,has been performed.The good agreement of the spectra from the simulation and experiment demonstrated the universality of this simulation method,which can be used to accurately measure neutroninduced light-charged particle emission reactions.展开更多
基金Projects(41877551,41842020)supported by the National Natural Science Foundation of ChinaProject(201509048)supported by the Environmental Protection’s Special Scientific Research for Chinese Public Welfare Industry
文摘Bauxite residue is a highly alkaline material generated from the production of alumina in which bauxite is dissolved in caustic soda.Approximately 4.4 billion tons of bauxite residues are either stockpiled or landfilled,creating environmental risks either from the generation of dust or migration of filtrates.High alkalinity is the critical factor restricting complete utilization of bauxite residues,whilst the application of alkaline regulation agents is costly and difficult to apply widely.For now,current industrial wastes,such as waste acid,ammonia nitrogen wastewater,waste gypsum and biomass,have become major problems restricting the development of the social economy.Regulation of bauxite residues alkalinity by industrial waste was proposed to achieve‘waste control by waste’with good economic and ecological benefits.This review will focus on the origin and transformation of alkalinity in bauxite residues using typical industrial waste.It will propose key research directions with an emphasis on alkaline regulation by industrial waste,whilst also providing a scientific reference point for their potential use as amendments to enhance soil formation and establish vegetation on bauxite residue disposal areas(BRDAs)following large-scale disposal.
基金Projects(41877511,41842020) supported by the National Natural Science Foundation of ChinaProject(201509048) supported by the Environmental Protection’s Special Scientific Research for Chinese Public Welfare Industry
文摘This study focused on leaching behavior of alkaline anion and sodium in bauxite residue through ammonium chloride treatment.The results showed that the pH of bauxite residue decreased from 10.49 to 8.93,total alkaline anion(HCO3^-,CO3^2-,OH^-,AlO2^-)concentration reduced from 38.89 to 25.50 mmol/L,leaching rate of soluble sodium was 80.86%with ammonium chloride addition of 0.75%,liquid/solid(L/S)ratio of 3(mL/g),temperature of 30°C and reaction time of 18 h;L/S ratio was the main factor affecting the removal of alkaline anion and the leaching of sodium.Furthermore,ammonium chloride promoted the dissolution of diaspore and changed the micro/morphological characteristics with the increase of massive structure.The findings of this work will contribute to achieve soil-formation of bauxite residue.
基金Project(41877511)supported by the National Natural Science Foundation of ChinaProject(201509048)supported by the Environmental Protection’s Special Scientific Research for the Chinese Public Welfare Industry,China
文摘Alkaline anions,include CO3^2–,HCO3^–,Al(OH)4^–,OH^–,continuously released from bauxite residue(BR),will cause a potential disastrous impact on surrounding environment.The composition variation of alkaline anions,alkaline phase transformation pathway,and micro-morphological transition characteristics during the gypsum addition were investigated in an attempt to understand alkalinity stabilization behavior.Results demonstrated that alkaline anions stabilization degree in leachates can reach approximately 96.29%,whilst pH and alkalinity were reduced from 10.47 to 8.15,47.39 mmol/L to 2 mmol/L,respectively.During the alkalinity stabilization,chemical regulation behavior plays significant role in driving the co-precipitation reaction among the critical alkaline anions(CO3^2–,HCO3^–,Al(OH)4^–,OH^–),with calcium carbonate(CaCO3))being the most prevalent among the transformed alkaline phases.In addition,XRD and SEM-EDX analyses of the solid phase revealed that physical immobilization behavior would also influence the stability of soluble alkali and chemical bonded alkali due to released Ca^2+from gypsum which aggregated the clay particles and stabilized them into coarse particles with a blocky structure.These findings will be beneficial for effectively regulating strong alkalinity of BR.
文摘[目的]探讨收肌管阻滞(adductor canal block,ACB)联合腘动脉与膝关节后囊间隙(interspace between the popliteal artery and capsule of the knee,IPACK)阻滞在全膝关节置换术(total knee arthroplasty,TKA)的镇痛效果。[方法]2020年2月—2022年6月84例终末期膝骨性关节炎患者在静脉全麻下进行初次单侧TKA术,依据术前医患沟通结果,42例采用ACB、PACK联合I阻滞(联合组),另外42例采用单纯ACB阻滞(ACB组),比较两组围手术期临床与镇痛相关资料。[结果]两组手术时间、总不良反应、术中失血量差异无统计学意义(P>0.05),联合组术后恢复下地行走显著早于ACB组[(18.5±4.3)h vs(30.4±6.7)h,P<0.001],联合组术后8 h[(69.3±7.3)°vs(64.8±6.9)°,P=0.005]、术后24 h[(70.1±6.3)°vs(65.2±6.7)°,P=0.001]膝ROM显著大于ACB组。术后2~24 h两组的VAS评分均有所上升,但联合组术后各时间点均显著低于ACB组(P<0.05),联合组首次补救镇痛时间[(6.3±1.8)h vs(10.4±2.3)h,P<0.001]、镇痛泵按压次数[(3.0±0.5)次vs(5.7±0.7)次,P<0.001]、使用血管活性药物次数[(1.0±0.2)次vs(1.7±0.4)次,P<0.001]、额外镇痛药使用次数[(1.4±0.4)次vs(1.9±0.6)次,P<0.001]均显著低于ACB组。[结论]ACB联合IPACK阻滞能够降低TKA术后疼痛症状,提升膝关节活动度,缩短恢复下床时间。
基金supported by the Natural Science Foundation of Jiangsu Province of China,No.BK20171180(to XRW)
文摘Rosmarinic acid,a common ester extracted from Rosemary,Perilla frutescens,and Salvia miltiorrhiza Bunge,has been shown to have protective effects against various diseases.This is an investigation into whether rosmarinic acid can also affect the changes of white matter fibers and cognitive deficits caused by hypoxic injury.The right common carotid artery of 3-day-old rats was ligated for 2 hours.The rats were then prewarmed in a plastic container with holes in the lid,which was placed in 37°C water bath for 30 minutes.Afterwards,the rats were exposed to an atmosphere with 8% O2 and 92% N2 for 30 minutes to establish the perinatal hypoxia/ischemia injury models.The rat models were intraperitoneally injected with rosmarinic acid 20 mg/kg for 5 consecutive days.At 22 days after birth,rosmarinic acid was found to improve motor,anxiety,learning and spatial memory impairments induced by hypoxia/ischemia injury.Furthermore,rosmarinic acid promoted the proliferation of oligodendrocyte progenitor cells in the subventricular zone.After hypoxia/ischemia injury,rosmarinic acid reversed to some extent the downregulation of myelin basic protein and the loss of myelin sheath in the corpus callosum of white matter structure.Rosmarinic acid partially slowed down the expression of oligodendrocyte marker Olig2 and myelin basic protein and the increase of oligodendrocyte apoptosis marker inhibitors of DNA binding 2.These data indicate that rosmarinic acid ameliorated the cognitive dysfunction after perinatal hypoxia/ischemia injury by improving remyelination in corpus callosum.This study was approved by the Animal Experimental Ethics Committee of Xuzhou Medical University,China (approval No.20161636721) on September 16,2017.
基金supported by the National Natural Science Foundation of China(No.12075008)Science and Technology on Nuclear Data Laboratory,China Nuclear Data Centerthe State Key Laboratory of Nuclear Physics and Technology,Peking University(No.NPT2020KFJ22)。
文摘A simulation method for measurement of the cross-section of the^(14)N(n,a)^(11)B reaction with gas and solid samples using a gridded ionization chamber(GIC)has been established.Using the simulation,the experimental spectra of both^(14)N(n,a)^(11)B events and background from other reactions can be predicted,and the experimental scheme can be optimized.According to the simulation results,the optimal experimental parameters,including the pressure of the working gas and the compositions of the working gas and the sample,can be determined.In addition,the simulation results can be used to determine the valid event area and calculate the detection efficiency for valid events.A measurement of the cross-sections of the^(14)N(n,a)^(11)B reaction at E_(n)=4.25,4.50,4.75,5.00,5.25,and 5.50 MeV,based on the 4.5-MV Van de Graff accelerator at Peking University(PKU)using a GIC as the detector for the outgoing a particles,has been performed.The good agreement of the spectra from the simulation and experiment demonstrated the universality of this simulation method,which can be used to accurately measure neutroninduced light-charged particle emission reactions.
