AIM To report data on Dilation-Assisted Stone Extraction(DASE) use in clinical practice and its efficacy and safety trough three Italian referral centers for biliopancreatic diseases treatment. METHODS From January 20...AIM To report data on Dilation-Assisted Stone Extraction(DASE) use in clinical practice and its efficacy and safety trough three Italian referral centers for biliopancreatic diseases treatment. METHODS From January 2011 to December 2015 we collected data on 120 patients treated with DASE. Technical success was obtained when the endoscopist was able to place the balloon trough the papilla inflating the balloon until the final diameter for an adequate time(at least 30 s). Clinical success was obtained after complete stone removal(no remaining stones were visible at the cholangiogram).RESULTS Forty-nine male(40.8%) and 71 female(59%) were enrolled. The mean age was 67.8 years ± 15.7. The mean common bile duct(CBD) dilation was 19.2 mm± 3.9 and the mean size of stones 15.8 ± 2.9. DASE was applied as first approach in 38%(62% after initial failure of stones extraction). Technical and clinical success was of 91% and 87% respectively. In those in which DASE failed alternative treatment were adopted. After DASE 18% of patients experienced a complication(bleeding 9%, pancreatitis 8%, perforation 0.8%). At univariable analysis, elective endoscopic retrograde cholangiopancreatography(P = 0.031), DASE as first approach(P = 0.032), and cannulation of major papilla followed by guidewire insertion(P = 0.004) were related to low risk of complications. Pre-cut was related to an increased risk of complications(P = 0.01). CONCLUSION DASE allowed a higher first-session success rate and can be consider a valid alternative to endoscopic sphincterotomy not only for bigger CBD stones.展开更多
Common bile duct stones are frequently diagnosed worldwide and are one of the main indications for endoscopic retrograde cholangio-pancreatography.Endoscopic sphincterotomy(EST)has been used for the removal of bile du...Common bile duct stones are frequently diagnosed worldwide and are one of the main indications for endoscopic retrograde cholangio-pancreatography.Endoscopic sphincterotomy(EST)has been used for the removal of bile duct stones for the past 40 years,providing a wide opening to allow extraction.Up to 15%of patients present with complicated choledocholithiasis.In this context,additional therapeutic approaches have been proposed such as endoscopic mechanical lithotripsy,intraductal or extracorporeal lithotripsy,or endoscopic papillary large balloon dilation(EPLBD).EPLBD combined with EST was introduced in 2003 to facilitate the passage of large or multiple bile duct stones using a balloon greater than 12 mm in diameter.EPLBD without EST was introduced as a simplified technique in 2009.Dilation-assisted stone extraction(DASE)is the combination of two techniques:EPLBD and sub-maximal EST.Several studies have reported this technique as safe and effective in patients with large bile duct stones,without any increased risk of adverse events such as pancreatitis,bleeding,or perforation.Nevertheless,it is difficult to analyze the outcomes of DASE because there are no standard techniques and definitions between studies.The purpose of this paper is to provide technical guidance and specific information about the main issues regarding DASE,based on current literature and daily clinical experience in biliary referral centers.展开更多
Experiments comparing microwave blank roasting and conventional blank roasting for typical vanadium-bearing stone coal from Hubei Province in central China, in which vanadium is present in muscovite, were conducted to...Experiments comparing microwave blank roasting and conventional blank roasting for typical vanadium-bearing stone coal from Hubei Province in central China, in which vanadium is present in muscovite, were conducted to investigate the effects of roasting tempera- ture, roasting time, H2SO4 concentration, and leaching time on vanadium extraction. The results show that the vanadium leaching efficiency is 84% when the sample is roasted at 800℃ for 30 min by microwave irradiation and the H2SO4 concentration, liquid/solid ratio, leaching temperature, and leaching time are set as 20vo1%, 1.5：1 mL.g-1, 95℃, and 8 h, respectively. However, the vanadium leaching efficiency achieved for the sample subjected to conventional roasting at 900℃ for 60 min is just 71% under the same leaching conditions. Scanning electron microscopy （SEM） analysis shows that the microwave roasted samples contain more cracks and that the particles are more porous compared to the conventionally roasted samples. According to the results of X-ray diffraction （XRD） and Fourier-transform infrared （FTIR） analyses, neither of these roasting methods could completely destroy the mica lattice structure under the experimental conditions; however, both methods deformed the muscovite structure and facilitated the leaching process. Comparing with conventional roasting, microwave roasting causes a greater deformation of the mineral structure at a lower temperature for a shorter roasting time.展开更多
Vanadium extraction from stone-coal was investigated by oxygen pressure acid leaching and solvent extraction.The mineralogy of the stone-coal from Tongren City of Guizhou Province,China,was investigated by various det...Vanadium extraction from stone-coal was investigated by oxygen pressure acid leaching and solvent extraction.The mineralogy of the stone-coal from Tongren City of Guizhou Province,China,was investigated by various determination methods. The effects of leaching time,leaching temperature,leaching agent concentration,leaching L/S ratio,granularity of material,additive consumption were investigated based on the mineralogy.The results show that under the conditions of leaching time of 3-4 h, temperature of 150℃,sulfuric acid consumption of 25%?30%,ratio of liquid to solid of 1.2:1,the granularity less than 0.074 mm, additive consumption of 3%-5%,and oxygen pressure of 1.2 MPa,and the vanadium leaching rate can be more than 92%by the method of two-step pressurized acid leaching.The powdery V2O5 product with 99.52%in V2O5 content is obtained by the flowsheet of acid recovery,removing iron by reduction process,solvent extraction,precipitating vanadium with ammonium water,and pyrolysis from the stone-coal oxygen pressure acid-leaching solution.The total recovery efficiency of vanadium is above 85%,which is more than 20%higher than that obtained in the conventional process.Furthermore,the new process does not cause air pollution since no HCl or Cl2 is released by calcination of the raw material.展开更多
The extraction technology of vanadium from stone coal by means of no-salt-roasting and dilute acid solution leaching treatment has the advantages of low pollution, low investment, as well as high vanadium leaching eff...The extraction technology of vanadium from stone coal by means of no-salt-roasting and dilute acid solution leaching treatment has the advantages of low pollution, low investment, as well as high vanadium leaching efficiency, which makes it the best technology for extending application. In the present study, the effects of vanadium occurrence state in stone coal, roasting temperature and additive agent on the leaching efficiency of vanadium were studied. The results indicate that the effect of vanadium occurrence state on the extracting vanadium technology is obvious. If the vanadium component in stone coal existed in amorphous phase form, this type of stone coal can be treated by no-slat-roasting and dilute acid solution leaching technology; while the vanadium-bearing crystalline phase existed in stone coal, the roasting additive must be added to destroy this crystalline form so as to acquire high vanadium leaching rate.展开更多
A new process of extracting vanadium from the stone coal vanadium ore in Fangshankou, Dtmhuang area of Gansu Province, China was introduced. Various leaching experiments were carried out, and the results show that the...A new process of extracting vanadium from the stone coal vanadium ore in Fangshankou, Dtmhuang area of Gansu Province, China was introduced. Various leaching experiments were carried out, and the results show that the vanadium ore in Fangshankou is difficult to process due to its high consumption of acid and the high leaching rate of impurities. However, the leaching rate can be up to 80% and the content of V2O5 in the residue can be between 0.22%-0.25% in the process of ore fme grinding→oxidation roasting→mixing and ripening→aqueous leaching→P2O4 solvent extraction→sulfuric acid stripping→oxidation and precipitation→decomposition by heat. Also, the quality of flaky V205 produced by this process can meet the requirements of GB3283--87. The total leaching rate of vanadium is 70%. Also, three types of wastes are easy to treat. The vanadium extraction process is better in relation to the aspect of environmental protection than the sodium method.展开更多
The critical role of vanadium in metallurgy and the increasing commercialization of vanadium redox flow batteries have contributed to a rise in market demand for vanadium,emphasizing the need to ensure the sustainabil...The critical role of vanadium in metallurgy and the increasing commercialization of vanadium redox flow batteries have contributed to a rise in market demand for vanadium,emphasizing the need to ensure the sustainability of vanadium production.Converter vanadium slag and stone coal,generated during the smelting process of vanadium–titanium magnetite,serve as primary raw materials for vanadium extraction.This paper reviews the process mineralogy of converter vanadium slag and stone coal,encompassing the chemical and physical phase compositions of the raw materials and the state of vanadium occurrence.The aim is to establish a theoretical foundation for the mechanistic study of the vanadium extraction techniques and to provide a reference for the optimization of the process afterward.This paper systematically summarizes the current vanadium extraction technology from converter vanadium slag,covering roasting,direct leaching,sub-molten salt method,and the technology and research status of vanadium extraction from stone coal.Most importantly,it identifies key issues in the current vanadium extraction techniques and challenges faced in actual production,based on the analysis of the current vanadium extraction process and mechanism research.The forward feasibility and prospects for the development of vanadium extraction technology are outlined.展开更多
This study examined the potential antilithic effects of a traditional Chinese medicine Urtica dentata Hand （UDH） in experimental rats and screened the optimal extract of UDH as a possible therapeutic agent for kidne...This study examined the potential antilithic effects of a traditional Chinese medicine Urtica dentata Hand （UDH） in experimental rats and screened the optimal extract of UDH as a possible therapeutic agent for kidney stones. The rat model of urinary calcium oxalate stones was induced by intragastric （i.g.） administration of 2 mL of 1.25% ethylene glycol （EG） and 1% ammonium chloride （AC） for 28 days and was confirmed by Color Doppler ultrasound imaging. The rats in different experimental groups were then intragastrically given petroleum ether extract （PEE）, N-butanol extract （NBE）, aqueous extract （AqE） of UDH, Jieshitong （positive control drug）, and saline, respectively. Treatment with NBE significantly reduced the elevated levels of urinary calcium, uric acid, phosphate, as well as increased urinary output. Accordingly, the increased calcium, oxalate levels and the number of calcium oxalate crystals deposits were remarkably reverted in the renal tissue of NBE-treated rats. In addition, NBE also prevented the impairment of renal function to decrease the contents of blood urea nitrogen （BUN） and creatinine. Taken together, these data suggest that NBE of UDH has a beneficial effect on calcium oxalate urinary stones in rats by flushing the stones out and protecting renal function.展开更多
Background:The choice of a basket or a balloon catheter during endoscopic retrograde cholangiopancreatography(ERCP)for the clearance of pancreatic duct stones in patients with chronic pancreatitis(CP)remains controver...Background:The choice of a basket or a balloon catheter during endoscopic retrograde cholangiopancreatography(ERCP)for the clearance of pancreatic duct stones in patients with chronic pancreatitis(CP)remains controversial.This study compared the efficacy and safety of these two devices for pancreatic duct stone extractions.Methods:We compared the efficacy and safety of basket and balloon catheters for pancreatic stone extractions.We enrolled CP patients who underwent ERCP for the first time at Changhai Hospital,Naval Medical University between February 2012 and December 2021.After propensity score matching(1:1),101 patients were included in each group.The primary outcome was the rate of pancreatic stone clearance.Secondary outcomes included the rate of adverse events during hospitalization,long-term pain relief,and quality of life after one year follow-up period.Results:The rate of complete clearance was comparable between the two groups(86.1%vs.84.2%,P=0.692).In patients with stones≥2 cm before extracorporeal shock wave lithotripsy(ESWL),the rate of complete clearance was significantly higher in the balloon catheter group when compared to the basket catheter group[100%(19/19)vs.70.0%(14/20),P=0.031].In the multivariate logistic analysis,ESWL prior to stone extraction was the only independent predictor of complete clearance[with ESWL 58.4%(264/452)vs.without ESWL 41.6%(188/452),odds ratio=2.3,95%confidence interval:1.2–4.3;P=0.013].No significant differences between groups were found regarding the rates of adverse events during hospitalization,quality of life,and pain relief after one year of follow-up.Conclusions:Basket and balloon catheters showed similar efficacy and safety for pancreatic stone extractions.However,the balloon catheter was superior to the basket catheter if the pancreatic stone size was≥2 cm before ESWL.展开更多
This study determined the optimal conditions required to obtain maximum vanadium extraction and examined the transition of mineral phases and vanadium speciation during the bioleaching process. Parameters including th...This study determined the optimal conditions required to obtain maximum vanadium extraction and examined the transition of mineral phases and vanadium speciation during the bioleaching process. Parameters including the initial p H value, initial Fe^(2+) concentration, solid load, and inoculum quantity were examined. The results revealed that 48.92 wt% of the vanadium was extracted through bioleaching under optimal conditions. Comparatively, the chemical leaching yield(H_2SO_4, pH 2.0) showed a slower and milder increase in vanadium yield. The vanadium bioleaching yield was 35.11 wt% greater than the chemical leaching yield. The Community Bureau of Reference(BCR) sequential extraction results revealed that 88.62 wt% of vanadium existed in the residual fraction. The bacteria substantially changed the distribution of the vanadium speciation during the leaching process, and the residual fraction decreased to 48.44 wt%. The X-ray diffraction(XRD) and Fourier transform infrared(FTIR) results provided evidence that the crystal lattice structure of muscovite was destroyed by the bacteria.展开更多
BACKGROUND:Mechanical lithotripsy and/or stent insertion is the alternative therapeutic approach in difficult endoscopic retrograde cholangiopancreatography (ERCP)case.This study was designed to investigate the approp...BACKGROUND:Mechanical lithotripsy and/or stent insertion is the alternative therapeutic approach in difficult endoscopic retrograde cholangiopancreatography (ERCP)case.This study was designed to investigate the appropriate treatment for extraction of bile duct stones in difficult cases of ERCP. METHODS:Between 2000 and 2008,744 ERCP procedures were performed in 592 patients with choledocholithiasis in our endoscopy unit.The demographic features,and clinical and laboratory findings were collected from a prospectively held database.Bile duct calculi were extracted by basket and/or balloon catheter following ERCP and sphincterotomy.Patients with retained stones were regarded as difficult cases.These patients were treated with mechanical lithotripsy and those with incomplete clearance of stones underwent stent placement. RESULTS:Two hundred and forty-five patients(41%) were male and 347(59%)were female with a mean age of 58 years(range 19-95 years).Stones were impacted in 27 patients(5%).Stone extraction was performed by basket and/or balloon catheter in 610 ERCP procedures,and lithotripsy was performed in 70 ERCP procedures.Forty- four patients underwent stent insertion,and 20 underwent stent replacement.Morbidity occurred in 39 patients (5%),with no mortality associated with the procedure.Hemorrhage occurred in 9 patients and basket impaction in 4.Mild pancreatitis and cholangitis developed in 12 and 11 patients,respectively. CONCLUSION:Difficult cases of bile duct stones can be treated successfully with lithotripsy,and a stent should be applied when the common bile duct cannot be cleared completely.展开更多
Phase change materials (PCMs) can be incorporated with low-cost minerals to synthesize composites for thermal energy storage in building applications.Stone coal (SC) after vanadium extraction treatment shows potential...Phase change materials (PCMs) can be incorporated with low-cost minerals to synthesize composites for thermal energy storage in building applications.Stone coal (SC) after vanadium extraction treatment shows potential for secondary utilization in composite preparation.We prepared SC-based composite PCMs with SC as a matrix,stearic acid (SA) as a PCM,and expanded graphite (EG) as an additive.The combined roasting and acid leaching treatment of raw SC was conducted to understand the effect of vanadium extraction on promoting loading capacity.Results showed that the combined treatment of roasting at 900℃ and leaching increased the SC loading of the composite by 6.2%by improving the specific surface area.The loading capacity and thermal conductivity of the composite obviously increased by 127%and 48.19%,respectively,due to the contribution of 3wt% EG.These data were supported by the high load of 66.69%and thermal conductivity of 0.59 W·m^(-1)·K-1of the designed composite.The obtained composite exhibited a phase change temperature of 52.17℃,melting latent heat of 121.5 J·g^(-1),and good chemical compatibility.The SC-based composite has prospects in building applications exploiting the secondary utilization of minerals.展开更多
The low-grade vanadium-containing stone coal used in this experiment was collected from Wuxi Country, Chongqing City, China. The experiment focused on the vanadium recovery from roasted residue through optimizing the ...The low-grade vanadium-containing stone coal used in this experiment was collected from Wuxi Country, Chongqing City, China. The experiment focused on the vanadium recovery from roasted residue through optimizing the process conditions of an effective and environmentally-friendly technology, named calcified roasting-sulfuric acid leaching technology. By single-factor experiments and orthogonal experiments, the effects of roasting temperature, roasting time, sulfuric acid concentration and leaching time on the leaching ratio of vanadium were analyzed. The results showed that the leaching ratio of vanadium reached 85.5% under the proper technological conditions of roasting temperature=950℃, roasting time=4 h, 40% concentration of sulfuric acid and leaching time=6 h.展开更多
Objective: to observe the therapeutic effect of plantain on calcium oxalate stone in urinary system of rats. Methods: rats were randomly divided into four groups: normal group, calcium oxalate stone model group, Paish...Objective: to observe the therapeutic effect of plantain on calcium oxalate stone in urinary system of rats. Methods: rats were randomly divided into four groups: normal group, calcium oxalate stone model group, Paishi granule treatment group and Plantago asiatica treatment group. Except for normal group, the other three groups were all given model-making agents (1% ethylene glycol and 2% ammonium chloride) for gastric lavage and model-making. Paishi granule treatment group and Plantago asiatica treatment group were treated with drugs while model-making. At the end of the experiment, the contents of calcium ions (Ca2+) and magnesium ions (Mg2+) in urine and calcium ions and urea nitrogen (BUN) in serum of rats in each group were detected. Results: compared with the model group, Plantago asiatica treatment group and Paishi granule treatment group can improve the life and mental state of rats, increase the micturition volume of rats, increase the excretion of calcium ions and magnesium ions in urine, and reduce the content of calcium ions and urea nitrogen in serum. Conclusion: the ethanol extract of Plantago asiatica can inhibit the formation of calcium oxalate stone by promoting the excretion of Ca2+, Mg2+ and BUN in urine and body, which is beneficial to the treatment of renal calcium oxalate stone in rats.展开更多
文摘AIM To report data on Dilation-Assisted Stone Extraction(DASE) use in clinical practice and its efficacy and safety trough three Italian referral centers for biliopancreatic diseases treatment. METHODS From January 2011 to December 2015 we collected data on 120 patients treated with DASE. Technical success was obtained when the endoscopist was able to place the balloon trough the papilla inflating the balloon until the final diameter for an adequate time(at least 30 s). Clinical success was obtained after complete stone removal(no remaining stones were visible at the cholangiogram).RESULTS Forty-nine male(40.8%) and 71 female(59%) were enrolled. The mean age was 67.8 years ± 15.7. The mean common bile duct(CBD) dilation was 19.2 mm± 3.9 and the mean size of stones 15.8 ± 2.9. DASE was applied as first approach in 38%(62% after initial failure of stones extraction). Technical and clinical success was of 91% and 87% respectively. In those in which DASE failed alternative treatment were adopted. After DASE 18% of patients experienced a complication(bleeding 9%, pancreatitis 8%, perforation 0.8%). At univariable analysis, elective endoscopic retrograde cholangiopancreatography(P = 0.031), DASE as first approach(P = 0.032), and cannulation of major papilla followed by guidewire insertion(P = 0.004) were related to low risk of complications. Pre-cut was related to an increased risk of complications(P = 0.01). CONCLUSION DASE allowed a higher first-session success rate and can be consider a valid alternative to endoscopic sphincterotomy not only for bigger CBD stones.
文摘Common bile duct stones are frequently diagnosed worldwide and are one of the main indications for endoscopic retrograde cholangio-pancreatography.Endoscopic sphincterotomy(EST)has been used for the removal of bile duct stones for the past 40 years,providing a wide opening to allow extraction.Up to 15%of patients present with complicated choledocholithiasis.In this context,additional therapeutic approaches have been proposed such as endoscopic mechanical lithotripsy,intraductal or extracorporeal lithotripsy,or endoscopic papillary large balloon dilation(EPLBD).EPLBD combined with EST was introduced in 2003 to facilitate the passage of large or multiple bile duct stones using a balloon greater than 12 mm in diameter.EPLBD without EST was introduced as a simplified technique in 2009.Dilation-assisted stone extraction(DASE)is the combination of two techniques:EPLBD and sub-maximal EST.Several studies have reported this technique as safe and effective in patients with large bile duct stones,without any increased risk of adverse events such as pancreatitis,bleeding,or perforation.Nevertheless,it is difficult to analyze the outcomes of DASE because there are no standard techniques and definitions between studies.The purpose of this paper is to provide technical guidance and specific information about the main issues regarding DASE,based on current literature and daily clinical experience in biliary referral centers.
基金financially supported by the Research Project from the Chinese Ministry of Education (No. 213025A)
文摘Experiments comparing microwave blank roasting and conventional blank roasting for typical vanadium-bearing stone coal from Hubei Province in central China, in which vanadium is present in muscovite, were conducted to investigate the effects of roasting tempera- ture, roasting time, H2SO4 concentration, and leaching time on vanadium extraction. The results show that the vanadium leaching efficiency is 84% when the sample is roasted at 800℃ for 30 min by microwave irradiation and the H2SO4 concentration, liquid/solid ratio, leaching temperature, and leaching time are set as 20vo1%, 1.5：1 mL.g-1, 95℃, and 8 h, respectively. However, the vanadium leaching efficiency achieved for the sample subjected to conventional roasting at 900℃ for 60 min is just 71% under the same leaching conditions. Scanning electron microscopy （SEM） analysis shows that the microwave roasted samples contain more cracks and that the particles are more porous compared to the conventionally roasted samples. According to the results of X-ray diffraction （XRD） and Fourier-transform infrared （FTIR） analyses, neither of these roasting methods could completely destroy the mica lattice structure under the experimental conditions; however, both methods deformed the muscovite structure and facilitated the leaching process. Comparing with conventional roasting, microwave roasting causes a greater deformation of the mineral structure at a lower temperature for a shorter roasting time.
基金Project(2006AA06Z130)supported by the High-tech Research and Development Program of ChinaProject(50874053)supported by the National Natural Science Foundation of ChinaProject(2007GA010)supported by Science and Technology Bureau of Yunnan Province,China
文摘Vanadium extraction from stone-coal was investigated by oxygen pressure acid leaching and solvent extraction.The mineralogy of the stone-coal from Tongren City of Guizhou Province,China,was investigated by various determination methods. The effects of leaching time,leaching temperature,leaching agent concentration,leaching L/S ratio,granularity of material,additive consumption were investigated based on the mineralogy.The results show that under the conditions of leaching time of 3-4 h, temperature of 150℃,sulfuric acid consumption of 25%?30%,ratio of liquid to solid of 1.2:1,the granularity less than 0.074 mm, additive consumption of 3%-5%,and oxygen pressure of 1.2 MPa,and the vanadium leaching rate can be more than 92%by the method of two-step pressurized acid leaching.The powdery V2O5 product with 99.52%in V2O5 content is obtained by the flowsheet of acid recovery,removing iron by reduction process,solvent extraction,precipitating vanadium with ammonium water,and pyrolysis from the stone-coal oxygen pressure acid-leaching solution.The total recovery efficiency of vanadium is above 85%,which is more than 20%higher than that obtained in the conventional process.Furthermore,the new process does not cause air pollution since no HCl or Cl2 is released by calcination of the raw material.
基金This work was financially supported by the Science Foundation of Central South University (No.76112037)the Postdoctoral Science Foundation of Central South University.
文摘The extraction technology of vanadium from stone coal by means of no-salt-roasting and dilute acid solution leaching treatment has the advantages of low pollution, low investment, as well as high vanadium leaching efficiency, which makes it the best technology for extending application. In the present study, the effects of vanadium occurrence state in stone coal, roasting temperature and additive agent on the leaching efficiency of vanadium were studied. The results indicate that the effect of vanadium occurrence state on the extracting vanadium technology is obvious. If the vanadium component in stone coal existed in amorphous phase form, this type of stone coal can be treated by no-slat-roasting and dilute acid solution leaching technology; while the vanadium-bearing crystalline phase existed in stone coal, the roasting additive must be added to destroy this crystalline form so as to acquire high vanadium leaching rate.
文摘A new process of extracting vanadium from the stone coal vanadium ore in Fangshankou, Dtmhuang area of Gansu Province, China was introduced. Various leaching experiments were carried out, and the results show that the vanadium ore in Fangshankou is difficult to process due to its high consumption of acid and the high leaching rate of impurities. However, the leaching rate can be up to 80% and the content of V2O5 in the residue can be between 0.22%-0.25% in the process of ore fme grinding→oxidation roasting→mixing and ripening→aqueous leaching→P2O4 solvent extraction→sulfuric acid stripping→oxidation and precipitation→decomposition by heat. Also, the quality of flaky V205 produced by this process can meet the requirements of GB3283--87. The total leaching rate of vanadium is 70%. Also, three types of wastes are easy to treat. The vanadium extraction process is better in relation to the aspect of environmental protection than the sodium method.
基金supported by the National Natural Science Foundation of China(Nos.51774140,82204604 and 22304055)Hebei Province High-end Iron and Steel Metallurgy Joint Fund Project(No.E2021209147)+4 种基金Hebei Natural Science Fund for Distinguished Young Scholar(No.E2019209433)the Natural Science Foundation of Hebei Province(No.E2022209158)the Science and Technology Planning Project of Hebei Province(No.23564101D)the Key Research Project of North China University of Science and Technology(No.ZD-ST-202308)the Operation Expenses for Universities’Basic Scientific Research of Hebei Province(No.JQN2021018)。
文摘The critical role of vanadium in metallurgy and the increasing commercialization of vanadium redox flow batteries have contributed to a rise in market demand for vanadium,emphasizing the need to ensure the sustainability of vanadium production.Converter vanadium slag and stone coal,generated during the smelting process of vanadium–titanium magnetite,serve as primary raw materials for vanadium extraction.This paper reviews the process mineralogy of converter vanadium slag and stone coal,encompassing the chemical and physical phase compositions of the raw materials and the state of vanadium occurrence.The aim is to establish a theoretical foundation for the mechanistic study of the vanadium extraction techniques and to provide a reference for the optimization of the process afterward.This paper systematically summarizes the current vanadium extraction technology from converter vanadium slag,covering roasting,direct leaching,sub-molten salt method,and the technology and research status of vanadium extraction from stone coal.Most importantly,it identifies key issues in the current vanadium extraction techniques and challenges faced in actual production,based on the analysis of the current vanadium extraction process and mechanism research.The forward feasibility and prospects for the development of vanadium extraction technology are outlined.
基金supported by a grant from the National Natural Sciences Foundation of China (No. 81073124)
文摘This study examined the potential antilithic effects of a traditional Chinese medicine Urtica dentata Hand （UDH） in experimental rats and screened the optimal extract of UDH as a possible therapeutic agent for kidney stones. The rat model of urinary calcium oxalate stones was induced by intragastric （i.g.） administration of 2 mL of 1.25% ethylene glycol （EG） and 1% ammonium chloride （AC） for 28 days and was confirmed by Color Doppler ultrasound imaging. The rats in different experimental groups were then intragastrically given petroleum ether extract （PEE）, N-butanol extract （NBE）, aqueous extract （AqE） of UDH, Jieshitong （positive control drug）, and saline, respectively. Treatment with NBE significantly reduced the elevated levels of urinary calcium, uric acid, phosphate, as well as increased urinary output. Accordingly, the increased calcium, oxalate levels and the number of calcium oxalate crystals deposits were remarkably reverted in the renal tissue of NBE-treated rats. In addition, NBE also prevented the impairment of renal function to decrease the contents of blood urea nitrogen （BUN） and creatinine. Taken together, these data suggest that NBE of UDH has a beneficial effect on calcium oxalate urinary stones in rats by flushing the stones out and protecting renal function.
基金supported by grants from the National Nat-ural Science Foundation of China(82222012 and 82120108006)Scientific Innovation Program of Shanghai Municipal Education Committee(201901070007E00052)。
文摘Background:The choice of a basket or a balloon catheter during endoscopic retrograde cholangiopancreatography(ERCP)for the clearance of pancreatic duct stones in patients with chronic pancreatitis(CP)remains controversial.This study compared the efficacy and safety of these two devices for pancreatic duct stone extractions.Methods:We compared the efficacy and safety of basket and balloon catheters for pancreatic stone extractions.We enrolled CP patients who underwent ERCP for the first time at Changhai Hospital,Naval Medical University between February 2012 and December 2021.After propensity score matching(1:1),101 patients were included in each group.The primary outcome was the rate of pancreatic stone clearance.Secondary outcomes included the rate of adverse events during hospitalization,long-term pain relief,and quality of life after one year follow-up period.Results:The rate of complete clearance was comparable between the two groups(86.1%vs.84.2%,P=0.692).In patients with stones≥2 cm before extracorporeal shock wave lithotripsy(ESWL),the rate of complete clearance was significantly higher in the balloon catheter group when compared to the basket catheter group[100%(19/19)vs.70.0%(14/20),P=0.031].In the multivariate logistic analysis,ESWL prior to stone extraction was the only independent predictor of complete clearance[with ESWL 58.4%(264/452)vs.without ESWL 41.6%(188/452),odds ratio=2.3,95%confidence interval:1.2–4.3;P=0.013].No significant differences between groups were found regarding the rates of adverse events during hospitalization,quality of life,and pain relief after one year of follow-up.Conclusions:Basket and balloon catheters showed similar efficacy and safety for pancreatic stone extractions.However,the balloon catheter was superior to the basket catheter if the pancreatic stone size was≥2 cm before ESWL.
基金financially supported by the Major Science and Technology Program for Water Pollution Control and Treatment of China (No. 2015ZX07205003)
文摘This study determined the optimal conditions required to obtain maximum vanadium extraction and examined the transition of mineral phases and vanadium speciation during the bioleaching process. Parameters including the initial p H value, initial Fe^(2+) concentration, solid load, and inoculum quantity were examined. The results revealed that 48.92 wt% of the vanadium was extracted through bioleaching under optimal conditions. Comparatively, the chemical leaching yield(H_2SO_4, pH 2.0) showed a slower and milder increase in vanadium yield. The vanadium bioleaching yield was 35.11 wt% greater than the chemical leaching yield. The Community Bureau of Reference(BCR) sequential extraction results revealed that 88.62 wt% of vanadium existed in the residual fraction. The bacteria substantially changed the distribution of the vanadium speciation during the leaching process, and the residual fraction decreased to 48.44 wt%. The X-ray diffraction(XRD) and Fourier transform infrared(FTIR) results provided evidence that the crystal lattice structure of muscovite was destroyed by the bacteria.
文摘BACKGROUND:Mechanical lithotripsy and/or stent insertion is the alternative therapeutic approach in difficult endoscopic retrograde cholangiopancreatography (ERCP)case.This study was designed to investigate the appropriate treatment for extraction of bile duct stones in difficult cases of ERCP. METHODS:Between 2000 and 2008,744 ERCP procedures were performed in 592 patients with choledocholithiasis in our endoscopy unit.The demographic features,and clinical and laboratory findings were collected from a prospectively held database.Bile duct calculi were extracted by basket and/or balloon catheter following ERCP and sphincterotomy.Patients with retained stones were regarded as difficult cases.These patients were treated with mechanical lithotripsy and those with incomplete clearance of stones underwent stent placement. RESULTS:Two hundred and forty-five patients(41%) were male and 347(59%)were female with a mean age of 58 years(range 19-95 years).Stones were impacted in 27 patients(5%).Stone extraction was performed by basket and/or balloon catheter in 610 ERCP procedures,and lithotripsy was performed in 70 ERCP procedures.Forty- four patients underwent stent insertion,and 20 underwent stent replacement.Morbidity occurred in 39 patients (5%),with no mortality associated with the procedure.Hemorrhage occurred in 9 patients and basket impaction in 4.Mild pancreatitis and cholangitis developed in 12 and 11 patients,respectively. CONCLUSION:Difficult cases of bile duct stones can be treated successfully with lithotripsy,and a stent should be applied when the common bile duct cannot be cleared completely.
基金financially supported by the National Natural Science Foundation of China, China (Nos. 52274252 and 51874047)the Special Fund for the Construction of Innovative Provinces in Hunan Province, China (No. 2020RC3038)the Changsha City Fund for Distinguished and Innovative Young Scholars, China (No. kq1802007)。
文摘Phase change materials (PCMs) can be incorporated with low-cost minerals to synthesize composites for thermal energy storage in building applications.Stone coal (SC) after vanadium extraction treatment shows potential for secondary utilization in composite preparation.We prepared SC-based composite PCMs with SC as a matrix,stearic acid (SA) as a PCM,and expanded graphite (EG) as an additive.The combined roasting and acid leaching treatment of raw SC was conducted to understand the effect of vanadium extraction on promoting loading capacity.Results showed that the combined treatment of roasting at 900℃ and leaching increased the SC loading of the composite by 6.2%by improving the specific surface area.The loading capacity and thermal conductivity of the composite obviously increased by 127%and 48.19%,respectively,due to the contribution of 3wt% EG.These data were supported by the high load of 66.69%and thermal conductivity of 0.59 W·m^(-1)·K-1of the designed composite.The obtained composite exhibited a phase change temperature of 52.17℃,melting latent heat of 121.5 J·g^(-1),and good chemical compatibility.The SC-based composite has prospects in building applications exploiting the secondary utilization of minerals.
基金the Scientific Research Foundation of State Key Lab.of Coal Mine Disaster Dynamics and Control(2011AD105827-MS201206)Scientific&Technologic Program for the Bureau of Land Resources and Housing Management of Chongqing
文摘The low-grade vanadium-containing stone coal used in this experiment was collected from Wuxi Country, Chongqing City, China. The experiment focused on the vanadium recovery from roasted residue through optimizing the process conditions of an effective and environmentally-friendly technology, named calcified roasting-sulfuric acid leaching technology. By single-factor experiments and orthogonal experiments, the effects of roasting temperature, roasting time, sulfuric acid concentration and leaching time on the leaching ratio of vanadium were analyzed. The results showed that the leaching ratio of vanadium reached 85.5% under the proper technological conditions of roasting temperature=950℃, roasting time=4 h, 40% concentration of sulfuric acid and leaching time=6 h.
文摘Objective: to observe the therapeutic effect of plantain on calcium oxalate stone in urinary system of rats. Methods: rats were randomly divided into four groups: normal group, calcium oxalate stone model group, Paishi granule treatment group and Plantago asiatica treatment group. Except for normal group, the other three groups were all given model-making agents (1% ethylene glycol and 2% ammonium chloride) for gastric lavage and model-making. Paishi granule treatment group and Plantago asiatica treatment group were treated with drugs while model-making. At the end of the experiment, the contents of calcium ions (Ca2+) and magnesium ions (Mg2+) in urine and calcium ions and urea nitrogen (BUN) in serum of rats in each group were detected. Results: compared with the model group, Plantago asiatica treatment group and Paishi granule treatment group can improve the life and mental state of rats, increase the micturition volume of rats, increase the excretion of calcium ions and magnesium ions in urine, and reduce the content of calcium ions and urea nitrogen in serum. Conclusion: the ethanol extract of Plantago asiatica can inhibit the formation of calcium oxalate stone by promoting the excretion of Ca2+, Mg2+ and BUN in urine and body, which is beneficial to the treatment of renal calcium oxalate stone in rats.
