The effects of polyaluminum chloride（PACl） hydrolysis prior to coagulation on both the coagulation zone and coagulation performance of a kaolin suspension were investigated by a novel jar test named the ＂reversed c...The effects of polyaluminum chloride（PACl） hydrolysis prior to coagulation on both the coagulation zone and coagulation performance of a kaolin suspension were investigated by a novel jar test named the ＂reversed coagulation test＂.The tests showed that PACl hydrolysis prior to coagulation decreased the performance of charge neutralization coagulation in the case of short-time slow mixing（10 min;G = 15 sec-1） and increased the optimal dosage for charge neutralization and sweep coagulation.Moreover,the hydrolysis time had insignificant effects on the size and zeta potential of PACl precipitates and the residual turbidity of the raw water.However,PACl hydrolysis prior to coagulation and the size of PACl precipitates had a negligible effect on the performance of sweep coagulation.The results imply that,in practice,preparing a PACl solution with deionized water,rather than tap water or the outlet water from a wastewater treatment unit,can significantly save PACl consumption and improve the performance of charge neutralization coagulation,while preparing the PACl solution with tap or outlet water would not affect the performance of sweep coagulation.In addition,the optimal rapid mixing intensity appears to be determined by a balance between the degree of coagulant hydrolysis before contacting the primary particles and the average size of flocs in the rapid mixing period.These results provide new insights into the role of PACl hydrolysis and will be useful for improving coagulation efficiency.展开更多
The microstructure significantly influences the superconducting properties.Herein,the defect structures and atomic arrangements in high-temperature Bi_(2)Sr_(2)CaCu_(2)O8_(+σ) superconducting wire are directly charac...The microstructure significantly influences the superconducting properties.Herein,the defect structures and atomic arrangements in high-temperature Bi_(2)Sr_(2)CaCu_(2)O8_(+σ) superconducting wire are directly characterized via stateof-the-art scanning transmission electron microscopy.Interstitial oxygen atoms are observed in both the charge reservoir layers and grain boundaries in the doped superconductor.Inclusion phases with varied numbers of CuO_(2) layers are found,and twist interfaces with different angles are identified.This study provides insights into the structures of Bi-2212 wire and lays the groundwork for guiding the design of microstructures and optimizing the production methods to enhance superconducting performance.展开更多
Background:Pancreatic ductal adenocarcinoma(PDAC)is in urgent need of a second‐line or later‐line treatment strategy.We aimed to analyze the efficacy and safety of additional anlotinib,specifically anlotinib in comb...Background:Pancreatic ductal adenocarcinoma(PDAC)is in urgent need of a second‐line or later‐line treatment strategy.We aimed to analyze the efficacy and safety of additional anlotinib,specifically anlotinib in combination with immunotherapy,in patients with PDAC who have failed first‐line therapy.Methods:Patients with pathological diagnosis of PDAC were additionally treated with anlotinib,and some patients were treated with anti‐PD‐1 agents at the same time,which could be retrospectively analyzed.The efficacy and safety of additional anlotinib were evaluated.Results:A total of 23 patients were included.In patients treated with additional anlotinib,the overall median progression‐free survival(PFS)was 1.8 months and the median overall survival(OS)was 6.3 months,regardless of anti‐PD‐1 agents.Among patients receiving additional anlotinib in combination with anti‐PD‐1 agents,median PFS and OS were 1.8 and 6.5 months,respectively.Adverse events(AEs)were observed in 16 patients(69.6%).In patients treated with additional anlotinib,the majority of AEs were grade 1–3.Univariate analysis revealed that patients with baseline red blood cell distribution width(RDW)<14%treated with additional anlotinib plus anti‐PD‐1 agents had significantly longer OS than patients with baseline RDW≥14%(p=0.025).Patients with additional anlotinib plus anti‐PD‐1 agents as second‐line therapy had a longer OS than those treated as later‐line therapy(p=0.012).Multivariate analysis showed that baseline RDW was the only independent risk factor for OS(p=0.042).Conclusion:The combination of anlotinib and immunotherapy represents an effective add‐on therapy with tolerable AEs as second‐or later‐line therapy in patients with PDAC,particularly in patients with baseline RDW<14%.展开更多
The production and application of organophosphate esters(OPEs)have dramatically increased in recent years due to their use as a replacement for brominated flame retardants.In this study,13 OPEs(∑_(13)OPEs)were analyz...The production and application of organophosphate esters(OPEs)have dramatically increased in recent years due to their use as a replacement for brominated flame retardants.In this study,13 OPEs(∑_(13)OPEs)were analyzed in indoor air samples from kitchens and living rooms in 14 residential homes in Beijing,China.The concentrations of ∑_(13)OPEs in kitchen air samples(mean:13 ng/m^(3))were significantly(p<0.05)higher than in living room air samples(5.0 ng/m^(3)).In addition,paired window surface organic film samples were collected and analyzed to investigate film-air partitioning,exhibiting a mean concentration of ∑_(13)OPEs of 4100 ng/m^(2).The congener profiles showed that tris(2-chloroisopropyl)phosphate(TCPP)was the predominant compound in both window film samples(48%)and the corresponding indoor air sample(56%).The estimated daily intakes(EDI)of OPEs via indoor air inhalation were 2.8 and 1.4 ng/kg/day for infants and adults,respectively,both of which are below the reference dose values(RfDs).Overall,these findings indicate that OPEs in the indoor air environment of residential homes in Beijing are not likely to pose a health risk to the general population.展开更多
Perfluorooctanoic acid(PFOA), its salts, and related compounds were listed as new persistent organic pollutants by the Stockholm Convention in 2019.In this study, the occurrence of residues of PFOA and other per-and p...Perfluorooctanoic acid(PFOA), its salts, and related compounds were listed as new persistent organic pollutants by the Stockholm Convention in 2019.In this study, the occurrence of residues of PFOA and other per-and polyfluoroalkyl substances(PFASs) in raw materials and fluoropolymer products from the Chinese fluoropolymer industries are reported for the first time.The PFOA concentrations in raw materials and fluoropolymer products were in the range of 6.7 to 1.1 × 10^(6) ng/g, and <MDL(method detection limit) to 5.3 × 10^(3) ng/g,respectively.Generally, the levels of PFOA in raw materials were higher than in products,implying that PFOA in the emulsion/dispersion resin could be partly removed during the polymerization or post-processing steps.By tracking a company’s polytetrafluoroethylene(PTFE) production line, it was found that over a 5 year period, the residual levels of PFOA in emulsion samples declined from 1.1 × 10^(6) to 28.4 ng/g, indicating that the contamination of PFOA in fluoropolymer products from production source gradually decreased after its use had been discontinued.High concentrations of HFPO-TrA(2.7 × 10^(5) to 8.2 × 10^(5) ng/g) were detected in some emulsion samples indicating this alternative has been widely applied in fluoropolymer manufacturing in China.展开更多
In this study,physicochemical,cluster,and high-throughput sequencing analyses were used to investigate the joint effects of salt and herbicide(glyphosate)stress factors on the microbial remediation of soil contaminate...In this study,physicochemical,cluster,and high-throughput sequencing analyses were used to investigate the joint effects of salt and herbicide(glyphosate)stress factors on the microbial remediation of soil contaminated by n-hexadecane and phenanthrene.Based on the soil’s physical and chemical properties,differences in microbial quantity and enzyme activities were analyzed among the samples,and how that influenced distribution of soil community structure was focused upon.After 120 days of indoor simulated remediation,the cumulative degradation rate of n-hexadecane decreased by 94.92%(blank control),96.96%(low concentration salt and glyphosate stress group),65.07%(high concentration salt and glyphosate stress group),while that of phenanthrene decreased by 87.33%(blank control),86.25%(low concentration salt and glyphosate stress group),58.45%(high concentration salt and glyphosate stress group).The combined stress of salt and herbicides was capable of lowering the reduction efficiency of organic matter,total nitrogen,and total phosphorus,and also restricting the growth of microorganisms and enzyme activities.Cluster analysis results indicated that the non-stress group was similar to the low-concentration compound stress group during different remedial period,whereas both of those differed starkly from the high-concentration compound stress group.High-throughput sequencing revealed that the dominant soil bacteria phyla shifted from Firmicutes to Actinobacteria within 120 days of remediation.展开更多
基金the Special Fund for the Technical Development of Scientific Research Institutionsfinanced by the Ministry of Science and Technology of the People's Republic of China(Nos.2011EG111307 and 2012EG111122)the Program for Overseas Talents of the Beijing Academy of Science and Technology(No.OTP-2013-015)
文摘The effects of polyaluminum chloride（PACl） hydrolysis prior to coagulation on both the coagulation zone and coagulation performance of a kaolin suspension were investigated by a novel jar test named the ＂reversed coagulation test＂.The tests showed that PACl hydrolysis prior to coagulation decreased the performance of charge neutralization coagulation in the case of short-time slow mixing（10 min;G = 15 sec-1） and increased the optimal dosage for charge neutralization and sweep coagulation.Moreover,the hydrolysis time had insignificant effects on the size and zeta potential of PACl precipitates and the residual turbidity of the raw water.However,PACl hydrolysis prior to coagulation and the size of PACl precipitates had a negligible effect on the performance of sweep coagulation.The results imply that,in practice,preparing a PACl solution with deionized water,rather than tap water or the outlet water from a wastewater treatment unit,can significantly save PACl consumption and improve the performance of charge neutralization coagulation,while preparing the PACl solution with tap or outlet water would not affect the performance of sweep coagulation.In addition,the optimal rapid mixing intensity appears to be determined by a balance between the degree of coagulant hydrolysis before contacting the primary particles and the average size of flocs in the rapid mixing period.These results provide new insights into the role of PACl hydrolysis and will be useful for improving coagulation efficiency.
文摘The microstructure significantly influences the superconducting properties.Herein,the defect structures and atomic arrangements in high-temperature Bi_(2)Sr_(2)CaCu_(2)O8_(+σ) superconducting wire are directly characterized via stateof-the-art scanning transmission electron microscopy.Interstitial oxygen atoms are observed in both the charge reservoir layers and grain boundaries in the doped superconductor.Inclusion phases with varied numbers of CuO_(2) layers are found,and twist interfaces with different angles are identified.This study provides insights into the structures of Bi-2212 wire and lays the groundwork for guiding the design of microstructures and optimizing the production methods to enhance superconducting performance.
文摘Background:Pancreatic ductal adenocarcinoma(PDAC)is in urgent need of a second‐line or later‐line treatment strategy.We aimed to analyze the efficacy and safety of additional anlotinib,specifically anlotinib in combination with immunotherapy,in patients with PDAC who have failed first‐line therapy.Methods:Patients with pathological diagnosis of PDAC were additionally treated with anlotinib,and some patients were treated with anti‐PD‐1 agents at the same time,which could be retrospectively analyzed.The efficacy and safety of additional anlotinib were evaluated.Results:A total of 23 patients were included.In patients treated with additional anlotinib,the overall median progression‐free survival(PFS)was 1.8 months and the median overall survival(OS)was 6.3 months,regardless of anti‐PD‐1 agents.Among patients receiving additional anlotinib in combination with anti‐PD‐1 agents,median PFS and OS were 1.8 and 6.5 months,respectively.Adverse events(AEs)were observed in 16 patients(69.6%).In patients treated with additional anlotinib,the majority of AEs were grade 1–3.Univariate analysis revealed that patients with baseline red blood cell distribution width(RDW)<14%treated with additional anlotinib plus anti‐PD‐1 agents had significantly longer OS than patients with baseline RDW≥14%(p=0.025).Patients with additional anlotinib plus anti‐PD‐1 agents as second‐line therapy had a longer OS than those treated as later‐line therapy(p=0.012).Multivariate analysis showed that baseline RDW was the only independent risk factor for OS(p=0.042).Conclusion:The combination of anlotinib and immunotherapy represents an effective add‐on therapy with tolerable AEs as second‐or later‐line therapy in patients with PDAC,particularly in patients with baseline RDW<14%.
基金This work was supported by the National Key Research and Development Program,China(No.2018YFC0213103)the National Natural Science Foundation of China(Nos.22021003,21625702).
文摘The production and application of organophosphate esters(OPEs)have dramatically increased in recent years due to their use as a replacement for brominated flame retardants.In this study,13 OPEs(∑_(13)OPEs)were analyzed in indoor air samples from kitchens and living rooms in 14 residential homes in Beijing,China.The concentrations of ∑_(13)OPEs in kitchen air samples(mean:13 ng/m^(3))were significantly(p<0.05)higher than in living room air samples(5.0 ng/m^(3)).In addition,paired window surface organic film samples were collected and analyzed to investigate film-air partitioning,exhibiting a mean concentration of ∑_(13)OPEs of 4100 ng/m^(2).The congener profiles showed that tris(2-chloroisopropyl)phosphate(TCPP)was the predominant compound in both window film samples(48%)and the corresponding indoor air sample(56%).The estimated daily intakes(EDI)of OPEs via indoor air inhalation were 2.8 and 1.4 ng/kg/day for infants and adults,respectively,both of which are below the reference dose values(RfDs).Overall,these findings indicate that OPEs in the indoor air environment of residential homes in Beijing are not likely to pose a health risk to the general population.
基金supported by the National Natural Science Foundation of China (No.21625702)。
文摘Perfluorooctanoic acid(PFOA), its salts, and related compounds were listed as new persistent organic pollutants by the Stockholm Convention in 2019.In this study, the occurrence of residues of PFOA and other per-and polyfluoroalkyl substances(PFASs) in raw materials and fluoropolymer products from the Chinese fluoropolymer industries are reported for the first time.The PFOA concentrations in raw materials and fluoropolymer products were in the range of 6.7 to 1.1 × 10^(6) ng/g, and <MDL(method detection limit) to 5.3 × 10^(3) ng/g,respectively.Generally, the levels of PFOA in raw materials were higher than in products,implying that PFOA in the emulsion/dispersion resin could be partly removed during the polymerization or post-processing steps.By tracking a company’s polytetrafluoroethylene(PTFE) production line, it was found that over a 5 year period, the residual levels of PFOA in emulsion samples declined from 1.1 × 10^(6) to 28.4 ng/g, indicating that the contamination of PFOA in fluoropolymer products from production source gradually decreased after its use had been discontinued.High concentrations of HFPO-TrA(2.7 × 10^(5) to 8.2 × 10^(5) ng/g) were detected in some emulsion samples indicating this alternative has been widely applied in fluoropolymer manufacturing in China.
基金This study was supported by the Open Project Program of State Key Laboratory of Petroleum Pollution Control(Grant No.PPC2019021)the Fundamental Reseach Funds for the central universities(22CX01004A-6)+1 种基金the CNPC Research Institute of Safety and Environmental Technology and CNPC Technology Innovation Fund Research Project(Grant Nos.2017D-5007-0601 and 2018D-5007-0605)the Research and Promotion Project of key technologies for safety and environmental protection of CNPC(2017D-4013).
文摘In this study,physicochemical,cluster,and high-throughput sequencing analyses were used to investigate the joint effects of salt and herbicide(glyphosate)stress factors on the microbial remediation of soil contaminated by n-hexadecane and phenanthrene.Based on the soil’s physical and chemical properties,differences in microbial quantity and enzyme activities were analyzed among the samples,and how that influenced distribution of soil community structure was focused upon.After 120 days of indoor simulated remediation,the cumulative degradation rate of n-hexadecane decreased by 94.92%(blank control),96.96%(low concentration salt and glyphosate stress group),65.07%(high concentration salt and glyphosate stress group),while that of phenanthrene decreased by 87.33%(blank control),86.25%(low concentration salt and glyphosate stress group),58.45%(high concentration salt and glyphosate stress group).The combined stress of salt and herbicides was capable of lowering the reduction efficiency of organic matter,total nitrogen,and total phosphorus,and also restricting the growth of microorganisms and enzyme activities.Cluster analysis results indicated that the non-stress group was similar to the low-concentration compound stress group during different remedial period,whereas both of those differed starkly from the high-concentration compound stress group.High-throughput sequencing revealed that the dominant soil bacteria phyla shifted from Firmicutes to Actinobacteria within 120 days of remediation.
