Herein,antibacterial silver‑doped fluorescent carbon dots(Ag‑CDs)were synthesized through a stepwise hydrothermal method,with polyethyleneimine(PEI),citric acid(CA),and silver nitrate(AgNO3)serving as precursors.The a...Herein,antibacterial silver‑doped fluorescent carbon dots(Ag‑CDs)were synthesized through a stepwise hydrothermal method,with polyethyleneimine(PEI),citric acid(CA),and silver nitrate(AgNO3)serving as precursors.The applicability and antimicrobial efficacy of these nanomaterials were systematically investigated for metal ion sensing.Experimental evidence demonstrated that the Ag‑CDs exhibited a pronounced fluorescence quenching response toward ferric ions(Fe^(3+)),enabling their quantitative determination via a linear concentration‑dependent relationship.These Ag‑CDs exhibited significant inhibitory effects on biofilm growth and disruption for both Escherichia coli and Staphylococcus aureus.Mechanism investigations indicate that Ag‑CDs induced the death of Escherichia coli and Pseudomonas aeruginosa by disrupting their bacterial morphology and structure,triggering the generation of intracellular reactive oxygen species(ROS),and impairing their antioxidant defense system.展开更多
为实现聚对苯二甲酸乙二醇酯(PET)的高效回收,基于聚对苯二甲酸乙二醇酯(PET)低聚物、尿素及均苯四甲酸(PMA)利用水热法高效制备PET基碳点(PET-CDs),得到较佳工艺条件:3 g PET低聚物、5 g PMA、4 g尿素、15 mL H_(2)O,260℃反应18 h。...为实现聚对苯二甲酸乙二醇酯(PET)的高效回收,基于聚对苯二甲酸乙二醇酯(PET)低聚物、尿素及均苯四甲酸(PMA)利用水热法高效制备PET基碳点(PET-CDs),得到较佳工艺条件:3 g PET低聚物、5 g PMA、4 g尿素、15 mL H_(2)O,260℃反应18 h。此外经研究发现,装载体积对PET基碳点(PET-CDs)荧光强度影响不大,可等比例放大至5 L反应釜中进行批量制备。对批量制备的PET-CDs进行表征,结果表明:PET-CDs为表面富含羟基、氨基的球形结构,平均粒径为1.37 nm;荧光为非激发波长依赖型,最佳激发波长为410 nm,最佳发射波长为485 nm,荧光量子产率高达70.78%。应用研究表明,将PET-CDs应用于聚己二酰己二胺(PA66)的共混阻燃改性时,PET-CDs的添加质量分数为4%时,极限氧指数达到28%,试样的第1次余焰时间从188.7 s降到5.2 s。PET-CDs荧光可被Fe 3+(0~10μmol/L)特异性猝灭,因此可采用PET-CDs为荧光探针对Fe 3+进行定量检测。所制备的PET-CDs还可用于防伪和指纹检测。展开更多
Ferromagnetic Fe3O4 nanoparticles were synthesized using water as the solvent through the sol-gel method, which was selected for its cost-effectiveness, simplicity, and eco-friendly nature. The synthesized nanoparticl...Ferromagnetic Fe3O4 nanoparticles were synthesized using water as the solvent through the sol-gel method, which was selected for its cost-effectiveness, simplicity, and eco-friendly nature. The synthesized nanoparticles were characterized using a variety of techniques, including Fourier Transform Infrared (FTIR) spectroscopy, X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA), and Vibrating Sample Magnetometer (VSM). These characterizations confirmed the successful formation of Fe3O4 nanoparticles. The FTIR spectra identified characteristic peaks corresponding to the functional groups present, and XRD analysis, using Scherer’s equation, determined an average crystalline size of 1.2 nm for the Fe3O4 nanoparticles. TGA results demonstrated the thermal stability of the nanoparticles, SEM imaging revealed distinct honeycomb-like structures for the nanoparticles synthesized with water as the solvent, while the VSM analysis was used to determine the magnetic behavior of the nanoparticles.展开更多
Bacterial spores commonly co-exist with vegetative cells,presenting challenges in spore separation and detection.The separation of spores is a crucial process for laboratory research and the detection of spore mechani...Bacterial spores commonly co-exist with vegetative cells,presenting challenges in spore separation and detection.The separation of spores is a crucial process for laboratory research and the detection of spore mechanisms.This study introduced a novel method that leverages the high binding affinity of vancomycin(Van)and ampicillin sodium(Amp)to vegetative cells,integrated with magnetic separation technology,to selectively collect spores from complex environments by eliminating vegetative cells.First,Van/Amp-modified magnetic Fe_(3)O_(4) nanoparticles(Fe_(3)O_(4) NPs)were synthesized and characterized.Subsequently,these NPs bound vegetative cells,forming magnetic conjugates that could be efficiently removed using a magnetic field.Concurrently,spores were collected with an efficiency exceeding 95%,completing the entire process within 30 min and achieving a spore separation efficiency of up to 10^(5) CFU/mL.This method was successfully applied to actual samples,including tap water and milk.The state of the collected spores was confirmed using Raman spectroscopy and microscopic techniques,verifying that their characteristics matched those of typical spores.The proposed novel method for rapid spore separation,leveraging the"remove bacterial effect'facilitated by Van/Amp-Fe_(3)O_(4) NPs,showed outstanding spore collection capabilities while preserving the excellent physiological state of spores.展开更多
Lanthanum-bearing iron lithium borate glass is a quaternary system for oxide glasses and was prepared via the melt-quenching method.The present article correlates the structure,optical,ligand field and M?ssbauer data ...Lanthanum-bearing iron lithium borate glass is a quaternary system for oxide glasses and was prepared via the melt-quenching method.The present article correlates the structure,optical,ligand field and M?ssbauer data on iron lithium borate glass co ntaining La^(3+).The density was measured,while the molar volume was calculated.Other physical parameters are well-described.With increasing the La_(2)O_(3) content within the glass network,infrared spectra analysis reveals structural modifications such as the increase in BO_(4) units and the decline in both BO_(3) units and NBO bonds content.Furthermore,optical absorption spectra were measured.The absorption spectra disclose a plethora of electronic transitions that are related to Fe^(3+)in tetrahedral and octahedral sites,however,Fe^(2+)phase is not observed in optical spectra,but it has a clear signature in M?ssbauer spectra.Besides,the glass absorption edges undergo a clear blue shift,reflecting an increased band gap energy(1.96-2.28 eV).The decline in NBO bonds justifies this trend.Bewitchingly,the values of crystal field splitting are increased,while the values of Racah parameters are decreased.This trend is justified by the decline in NBO bonds and increases electron localization around Fe cations.M?ssbauer spectra confirm the existence of Fe^(3+)in tetrahedral and octahedral sites,while Fe^(2+)exists in only a tetrahedral state.With increasing La_(2)O_(3) content,the isomer shift of Fe^(3+)in tetrahedral sites changes to be 0.312-0.329 mm/s,while the isomer shift of octahedral Fe^(3+)is 0.424-0.456 mm/s.These findings coincide with optical data.While the isomer shift of tetrahedral Fe^(2+)is 0.902-0.911 mm/s.Our results of structural,optical and ligand field associated with M?ssbauer spectra open more vistas toward the utility of these samples in the optics realm.展开更多
Noble metal-loaded layered hydroxides exhibit high efficiency in electrocatalyzing water splitting.However,their widespread use as bifunctional electrocatalysts is hindered by low metal loading,inefficient yield,and c...Noble metal-loaded layered hydroxides exhibit high efficiency in electrocatalyzing water splitting.However,their widespread use as bifunctional electrocatalysts is hindered by low metal loading,inefficient yield,and complex synthesis processes.In this work,platinum atoms were anchored onto nickel-iron layered double hydroxide/carbon nanotube(LDH/CNT)hybrid electrocatalysts by using a straightforward milling technique with K_(2)Pt Cl_(6)·6H_(2)O as the Pt source.By adjusting the Pt-to-Fe ratio to 1/2 and 1/10,excellent electrocatalysts—Pt_(1/6)-Ni_(2/3)Fe_(1/3)-LDH/CNT and Pt_(1/30)-Ni_(2/3)Fe_(1/3)-LDH/CNT—were achieved with superior performance in hydrogen evolution reaction(HER)and oxygen evolution reaction(OER),outperforming the corresponding commercial Pt/C(20 wt%)and Ru O_(2)electrocatalysts.The enhanced electrochemical performance is attributed to the modification of Pt's electronic structure,which exhibits electron-rich states for HER and electrondeficient states for OER,significantly boosting Pt's electrochemical activity.Furthermore,the simple milling technology for controlling Pt loading offers a promising approach for scaling up the production of electrocatalysts.展开更多
Background:The traditional Sox10 ^(Dom/+)mouse breeding strategy is costly and timeconsuming,so this study aims to optimize the breeding method and improve the scientific research efficiency.Methods:We select the offs...Background:The traditional Sox10 ^(Dom/+)mouse breeding strategy is costly and timeconsuming,so this study aims to optimize the breeding method and improve the scientific research efficiency.Methods:We select the offspring from mating B6C3Fe Sox10 ^(Dom/+)male mice with C57BL/6J female mice,and name the progeny B6C3Fe-g.Further,conduct separate self-breeding for both the B6C3Fe and B6C3Fe-g strains,adhering to the principle of pairing mutants with non-mutants.By comparing the number of offspring,survival rates,and the phenotype of aganglionosis in the colon,a comprehensive evaluation of their breeding capacity and phenotypic stability is conducted.Results:Sanger sequencing results show that the mutation sites of B6C3Fe and B6C3Fe-g mice are consistent.After fluorescent staining of intestinal nerves,it was found that the heterozygous mice of the two strains had neuronal deletion in the distal colon,and this pathological phenotype was consistent with the pathological features of the diseased colon of Hirschsprung disease(HSCR).However,compared with the B6C3Fe strain,the B6C3Fe-g strain has a higher number of offspring and greater survival rates.Conclusions:The breeding strategy of the B6C3Fe-g strain ensures genetic and phenotypic stability,while improving reproductive efficiency,and is an ideal scheme for breeding Sox10 ^(Dom/+)mice.展开更多
文摘Herein,antibacterial silver‑doped fluorescent carbon dots(Ag‑CDs)were synthesized through a stepwise hydrothermal method,with polyethyleneimine(PEI),citric acid(CA),and silver nitrate(AgNO3)serving as precursors.The applicability and antimicrobial efficacy of these nanomaterials were systematically investigated for metal ion sensing.Experimental evidence demonstrated that the Ag‑CDs exhibited a pronounced fluorescence quenching response toward ferric ions(Fe^(3+)),enabling their quantitative determination via a linear concentration‑dependent relationship.These Ag‑CDs exhibited significant inhibitory effects on biofilm growth and disruption for both Escherichia coli and Staphylococcus aureus.Mechanism investigations indicate that Ag‑CDs induced the death of Escherichia coli and Pseudomonas aeruginosa by disrupting their bacterial morphology and structure,triggering the generation of intracellular reactive oxygen species(ROS),and impairing their antioxidant defense system.
文摘Ferromagnetic Fe3O4 nanoparticles were synthesized using water as the solvent through the sol-gel method, which was selected for its cost-effectiveness, simplicity, and eco-friendly nature. The synthesized nanoparticles were characterized using a variety of techniques, including Fourier Transform Infrared (FTIR) spectroscopy, X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA), and Vibrating Sample Magnetometer (VSM). These characterizations confirmed the successful formation of Fe3O4 nanoparticles. The FTIR spectra identified characteristic peaks corresponding to the functional groups present, and XRD analysis, using Scherer’s equation, determined an average crystalline size of 1.2 nm for the Fe3O4 nanoparticles. TGA results demonstrated the thermal stability of the nanoparticles, SEM imaging revealed distinct honeycomb-like structures for the nanoparticles synthesized with water as the solvent, while the VSM analysis was used to determine the magnetic behavior of the nanoparticles.
基金supported by the General Program of National Natural Science Foundation of China(32472417)the Major Science and Technology Projects in Henan Province(221100110500,231100110400)+2 种基金the Science and Technology Innovation Team of Henan Universities(22IRTSTHN021)the Science and Technology of Henan Province(232102110136)Henan Provincial Joint Fund(Science and Technology Tackling)Category(232103810023).
文摘Bacterial spores commonly co-exist with vegetative cells,presenting challenges in spore separation and detection.The separation of spores is a crucial process for laboratory research and the detection of spore mechanisms.This study introduced a novel method that leverages the high binding affinity of vancomycin(Van)and ampicillin sodium(Amp)to vegetative cells,integrated with magnetic separation technology,to selectively collect spores from complex environments by eliminating vegetative cells.First,Van/Amp-modified magnetic Fe_(3)O_(4) nanoparticles(Fe_(3)O_(4) NPs)were synthesized and characterized.Subsequently,these NPs bound vegetative cells,forming magnetic conjugates that could be efficiently removed using a magnetic field.Concurrently,spores were collected with an efficiency exceeding 95%,completing the entire process within 30 min and achieving a spore separation efficiency of up to 10^(5) CFU/mL.This method was successfully applied to actual samples,including tap water and milk.The state of the collected spores was confirmed using Raman spectroscopy and microscopic techniques,verifying that their characteristics matched those of typical spores.The proposed novel method for rapid spore separation,leveraging the"remove bacterial effect'facilitated by Van/Amp-Fe_(3)O_(4) NPs,showed outstanding spore collection capabilities while preserving the excellent physiological state of spores.
文摘Lanthanum-bearing iron lithium borate glass is a quaternary system for oxide glasses and was prepared via the melt-quenching method.The present article correlates the structure,optical,ligand field and M?ssbauer data on iron lithium borate glass co ntaining La^(3+).The density was measured,while the molar volume was calculated.Other physical parameters are well-described.With increasing the La_(2)O_(3) content within the glass network,infrared spectra analysis reveals structural modifications such as the increase in BO_(4) units and the decline in both BO_(3) units and NBO bonds content.Furthermore,optical absorption spectra were measured.The absorption spectra disclose a plethora of electronic transitions that are related to Fe^(3+)in tetrahedral and octahedral sites,however,Fe^(2+)phase is not observed in optical spectra,but it has a clear signature in M?ssbauer spectra.Besides,the glass absorption edges undergo a clear blue shift,reflecting an increased band gap energy(1.96-2.28 eV).The decline in NBO bonds justifies this trend.Bewitchingly,the values of crystal field splitting are increased,while the values of Racah parameters are decreased.This trend is justified by the decline in NBO bonds and increases electron localization around Fe cations.M?ssbauer spectra confirm the existence of Fe^(3+)in tetrahedral and octahedral sites,while Fe^(2+)exists in only a tetrahedral state.With increasing La_(2)O_(3) content,the isomer shift of Fe^(3+)in tetrahedral sites changes to be 0.312-0.329 mm/s,while the isomer shift of octahedral Fe^(3+)is 0.424-0.456 mm/s.These findings coincide with optical data.While the isomer shift of tetrahedral Fe^(2+)is 0.902-0.911 mm/s.Our results of structural,optical and ligand field associated with M?ssbauer spectra open more vistas toward the utility of these samples in the optics realm.
基金supported by the Natural Science Foundation of Henan(242300421230)the Young Teacher Fundamental Research Cultivation Program of Zhengzhou University(JC23557030)the National Natural Science Foundation of China(U21A20281 and 22208322)。
文摘Noble metal-loaded layered hydroxides exhibit high efficiency in electrocatalyzing water splitting.However,their widespread use as bifunctional electrocatalysts is hindered by low metal loading,inefficient yield,and complex synthesis processes.In this work,platinum atoms were anchored onto nickel-iron layered double hydroxide/carbon nanotube(LDH/CNT)hybrid electrocatalysts by using a straightforward milling technique with K_(2)Pt Cl_(6)·6H_(2)O as the Pt source.By adjusting the Pt-to-Fe ratio to 1/2 and 1/10,excellent electrocatalysts—Pt_(1/6)-Ni_(2/3)Fe_(1/3)-LDH/CNT and Pt_(1/30)-Ni_(2/3)Fe_(1/3)-LDH/CNT—were achieved with superior performance in hydrogen evolution reaction(HER)and oxygen evolution reaction(OER),outperforming the corresponding commercial Pt/C(20 wt%)and Ru O_(2)electrocatalysts.The enhanced electrochemical performance is attributed to the modification of Pt's electronic structure,which exhibits electron-rich states for HER and electrondeficient states for OER,significantly boosting Pt's electrochemical activity.Furthermore,the simple milling technology for controlling Pt loading offers a promising approach for scaling up the production of electrocatalysts.
基金Basic and Applied Basic Research Foundation of Guangxi Province of China,Grant/Award Number:2025GXNSFBA069072National Natural Science Foundation of China,Grant/Award Number:81970450,82070528,82170528,82200561,82201893,82301955,82370526 and 82560108+2 种基金Medical Scientific Research Foundation of Guangdong Province of China,Grant/Award Number:A2024374The Guangdong Basic and Applied Basic Research Foundation,Grant/Award Number:2024A03J1171,2024A03J1238 and 2024A1515013190Science and Technology Projects in Guangzhou,Grant/Award Number:202201020006。
文摘Background:The traditional Sox10 ^(Dom/+)mouse breeding strategy is costly and timeconsuming,so this study aims to optimize the breeding method and improve the scientific research efficiency.Methods:We select the offspring from mating B6C3Fe Sox10 ^(Dom/+)male mice with C57BL/6J female mice,and name the progeny B6C3Fe-g.Further,conduct separate self-breeding for both the B6C3Fe and B6C3Fe-g strains,adhering to the principle of pairing mutants with non-mutants.By comparing the number of offspring,survival rates,and the phenotype of aganglionosis in the colon,a comprehensive evaluation of their breeding capacity and phenotypic stability is conducted.Results:Sanger sequencing results show that the mutation sites of B6C3Fe and B6C3Fe-g mice are consistent.After fluorescent staining of intestinal nerves,it was found that the heterozygous mice of the two strains had neuronal deletion in the distal colon,and this pathological phenotype was consistent with the pathological features of the diseased colon of Hirschsprung disease(HSCR).However,compared with the B6C3Fe strain,the B6C3Fe-g strain has a higher number of offspring and greater survival rates.Conclusions:The breeding strategy of the B6C3Fe-g strain ensures genetic and phenotypic stability,while improving reproductive efficiency,and is an ideal scheme for breeding Sox10 ^(Dom/+)mice.
