Three-dimensional C/SiOx nanofiber anode was prepared by polydimethylsiloxane(PDMS)and polyacrylonitrile(PAN)as precursors via electrospinning and freeze-drying successfully.In contrast to conventional carbon cover-ing...Three-dimensional C/SiOx nanofiber anode was prepared by polydimethylsiloxane(PDMS)and polyacrylonitrile(PAN)as precursors via electrospinning and freeze-drying successfully.In contrast to conventional carbon cover-ing Si-based anode materials,the C/SiOx structure is made up of PAN-C,a 3D carbon substance,and SiOx load-ing steadily on PAN-C.The PAN carbon nanofibers and loaded SiOx from pyrolyzed PDMS give increased conductivity and a stable complex structure.When employed as lithium-ion batteries(LIBs)anode materials,C/SiOx-1%composites were discovered to have an extremely high lithium storage capacity and good cycle per-formance.At a current density of 100 mA/g,its reversible capacity remained at 761 mA/h after 50 charge-dis-charge cycles and at 670 mA/h after 200 cycles.The C/SiOx-1%composite aerogel is a particularly intriguing anode candidate for high-performance LIBs due to these appealing qualities.展开更多
Drug-resistant bacteria present a severe threat to public health,emphasizing the importance of developing broad-spectrum antibacterial agents that are free from drug resistance.Among silver-based antibacterial agents,...Drug-resistant bacteria present a severe threat to public health,emphasizing the importance of developing broad-spectrum antibacterial agents that are free from drug resistance.Among silver-based antibacterial agents,nano-silver has been found to exhibit the most promising and comprehensive performance.The exploration of the antibacterial capacity and morphological changes of silver nanoparticles(AgNPs)could offer a starting point for the development of safe and efficient antibacterial agents.In this study,three types of nano-silver-modified polyphosphazene(PRV)nanoparticles with different morphologies were synthesized using precipitation polymerization.These nanoparticles were characterized using various techniques,including Fourier-transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),and thermogravimetric analysis(TGA).The antibacterial activity of these nanoparticles against Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)was assessed using minimum inhibitory concentration(MiC)/minimum bactericidal concentration(MBC)tests and inverted fluorescence microscopy.Our results revealed that the antibacterial activity of silver nanoparticles can vary significantly depending on their immobilized form.Ag@PRV Strawberry-like nanoparticles(NPs)exhibited higher antibacterial activity compared to Ag@PRV Yolk-Shell NPs and Ag@PRV Cable-like nanofibers(NFs).Notably,all three types of synthesized nanoparticles demonstrated a stronger bactericidal effect on Gram-positive bacteria than Gram-negative bacteria.Live/dead bacterial staining and scanning electron microscopy demonstrated that silver can kill bacteria by altering the permeability of their cell membranes.These findings offer valuable insights for designing and practically applying new silver-based antibacterial agents in the future.展开更多
Lignin is the most abundant and important macromolecule in organic matter and its yield is second only to cellulose. Lignin is abundant in source, low in price, and has a large number of active groups such as methoxy ...Lignin is the most abundant and important macromolecule in organic matter and its yield is second only to cellulose. Lignin is abundant in source, low in price, and has a large number of active groups such as methoxy group and carboxyl group, so it has great utilization value. We used lignin as a carbon source to prepare porous carbon nanosphere(PCN) materials, and in-situ synthesized the MoS_ 2 on its surface. The high specific surface area(462.8 m^2/g), large pore volume and good electron conductivity of the porous carbon scaffold facilitated the reversible electro-chemical reaction of S towards metallic Li, and thus the nano-hybrid showed a high specific energy and excellent cycle stability which still remained 520m Ah/g after 50 cycles.展开更多
In this work,the (1-x)Bi_(0.5)Na_(0.5)TiO_(3)-xBaNi_(0.5)Nb_(0.5)O_(3)(BNT-BNN;0.00≤x≤ 0.20)ceramics were prepared via a high-temperature solid-state method.The crystalline structures,photovoltaic effect,and electri...In this work,the (1-x)Bi_(0.5)Na_(0.5)TiO_(3)-xBaNi_(0.5)Nb_(0.5)O_(3)(BNT-BNN;0.00≤x≤ 0.20)ceramics were prepared via a high-temperature solid-state method.The crystalline structures,photovoltaic effect,and electrical properties of the ceramics were investigated.According to X-ray diffraction,the system shows a single perovskite structure.The samples show the normal ferroelectric loops.With the increase of BNN content,the remnant polarization(P_(r))and coercive field(E_(c))decrease gradually.The optical band gap of the samples narrows from 3.10 to 2.27 eV.The conductive species of grains and grain boundaries in the ceramics are ascribed to the double ionized oxygen vacancies.The open-circuit voltage(V_(∝))of ~15.7 V and short-circuit current(J_(sc))of ~1450 nA/cm^(2) are obtained in the 0.95BNT-0.05BNN ceramic under 1 sun illumination(AM1.5G,100 mW/cm^(2)).A larger V_(∝) of 23 V and a higher J_(sc) of 5500 nA/cm^(2) are achieved at the poling field of 60 kV/cm under the same light conditions.The study shows this system has great application prospects in the photovoltaic field.展开更多
基金We are thankful for the Project Supported by the Zhejiang Provincial Natural Science Foundation of China(GB21031200070)National Natural Science Foundation of China(C125020173)for the support to this research.
文摘Three-dimensional C/SiOx nanofiber anode was prepared by polydimethylsiloxane(PDMS)and polyacrylonitrile(PAN)as precursors via electrospinning and freeze-drying successfully.In contrast to conventional carbon cover-ing Si-based anode materials,the C/SiOx structure is made up of PAN-C,a 3D carbon substance,and SiOx load-ing steadily on PAN-C.The PAN carbon nanofibers and loaded SiOx from pyrolyzed PDMS give increased conductivity and a stable complex structure.When employed as lithium-ion batteries(LIBs)anode materials,C/SiOx-1%composites were discovered to have an extremely high lithium storage capacity and good cycle per-formance.At a current density of 100 mA/g,its reversible capacity remained at 761 mA/h after 50 charge-dis-charge cycles and at 670 mA/h after 200 cycles.The C/SiOx-1%composite aerogel is a particularly intriguing anode candidate for high-performance LIBs due to these appealing qualities.
基金financially supported by the Ningbo Scientific and Technological Innovation 2025 Major Project(No.2020Z097)Natural Science Foundation of Zhejiang Province(No.LY18E030009)+1 种基金Ningbo Clinical Research Center for Otolaryngology Head and Neck Disease(No.2022L005)Ningbo Medical and Health Brand Discipline(No.PPXK2018-02).
文摘Drug-resistant bacteria present a severe threat to public health,emphasizing the importance of developing broad-spectrum antibacterial agents that are free from drug resistance.Among silver-based antibacterial agents,nano-silver has been found to exhibit the most promising and comprehensive performance.The exploration of the antibacterial capacity and morphological changes of silver nanoparticles(AgNPs)could offer a starting point for the development of safe and efficient antibacterial agents.In this study,three types of nano-silver-modified polyphosphazene(PRV)nanoparticles with different morphologies were synthesized using precipitation polymerization.These nanoparticles were characterized using various techniques,including Fourier-transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),and thermogravimetric analysis(TGA).The antibacterial activity of these nanoparticles against Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)was assessed using minimum inhibitory concentration(MiC)/minimum bactericidal concentration(MBC)tests and inverted fluorescence microscopy.Our results revealed that the antibacterial activity of silver nanoparticles can vary significantly depending on their immobilized form.Ag@PRV Strawberry-like nanoparticles(NPs)exhibited higher antibacterial activity compared to Ag@PRV Yolk-Shell NPs and Ag@PRV Cable-like nanofibers(NFs).Notably,all three types of synthesized nanoparticles demonstrated a stronger bactericidal effect on Gram-positive bacteria than Gram-negative bacteria.Live/dead bacterial staining and scanning electron microscopy demonstrated that silver can kill bacteria by altering the permeability of their cell membranes.These findings offer valuable insights for designing and practically applying new silver-based antibacterial agents in the future.
基金the financial support of National Natural Science Foundation of China (No. 51803062)National Natural Science Foundation of Guangdong Province (No. 2018A030310379)+4 种基金National Postdoctoral Program for Innovation Talents (No. BX201700079)China Postdoctoral Science Foundation Funded Project (No. 2017M620371)and Foundation for Distinguished Young Talents in Higher Education of Guangdong Province (No. 2017KQNCX001)F. Chen thanks the financialsupport of Natural Science Foundation of China (No. 51673175)Natural Science Foundation of Zhejiang Province (Nos. LY16E030012, LY17E030006 and LY18E030009)
文摘Lignin is the most abundant and important macromolecule in organic matter and its yield is second only to cellulose. Lignin is abundant in source, low in price, and has a large number of active groups such as methoxy group and carboxyl group, so it has great utilization value. We used lignin as a carbon source to prepare porous carbon nanosphere(PCN) materials, and in-situ synthesized the MoS_ 2 on its surface. The high specific surface area(462.8 m^2/g), large pore volume and good electron conductivity of the porous carbon scaffold facilitated the reversible electro-chemical reaction of S towards metallic Li, and thus the nano-hybrid showed a high specific energy and excellent cycle stability which still remained 520m Ah/g after 50 cycles.
基金financially supported by the National Natural Science Foundation of China(Grant No.11464006)Guangxi Key Laboratory of Information Materials(Grant No.191026-Z).
文摘In this work,the (1-x)Bi_(0.5)Na_(0.5)TiO_(3)-xBaNi_(0.5)Nb_(0.5)O_(3)(BNT-BNN;0.00≤x≤ 0.20)ceramics were prepared via a high-temperature solid-state method.The crystalline structures,photovoltaic effect,and electrical properties of the ceramics were investigated.According to X-ray diffraction,the system shows a single perovskite structure.The samples show the normal ferroelectric loops.With the increase of BNN content,the remnant polarization(P_(r))and coercive field(E_(c))decrease gradually.The optical band gap of the samples narrows from 3.10 to 2.27 eV.The conductive species of grains and grain boundaries in the ceramics are ascribed to the double ionized oxygen vacancies.The open-circuit voltage(V_(∝))of ~15.7 V and short-circuit current(J_(sc))of ~1450 nA/cm^(2) are obtained in the 0.95BNT-0.05BNN ceramic under 1 sun illumination(AM1.5G,100 mW/cm^(2)).A larger V_(∝) of 23 V and a higher J_(sc) of 5500 nA/cm^(2) are achieved at the poling field of 60 kV/cm under the same light conditions.The study shows this system has great application prospects in the photovoltaic field.