The searches for large-gap quantum spin Hall insulators are important for both practical and fundamental inter- ests. In this work, we present a theoretical observation of the two-dimensional fully fluorinated stanene...The searches for large-gap quantum spin Hall insulators are important for both practical and fundamental inter- ests. In this work, we present a theoretical observation of the two-dimensional fully fluorinated stanene （SnF） by means of density functional theory. Remarkably, a significant spin-orbit coupling is observed for the SnF monolayer in the valence band at the F point, with a considerable indirect band gap of 278 meV. The direct gap of the SnF monolayer is at the F point, which is slightly larger by as much as 381 meV. In addition, the elastic modulus of the SnF monolayer is about 20J/m^2, which is comparable with the in-plane stiffness of black phos- phorus monolayer along the x-direction （~28.94 J/m^2）. Finally, the optical properties of stanene, SnF monolayer and stanene/SnF bilayer are calculated, in which the stanene/SnF bilayer is supposed to be an attractive sunlight absorber.展开更多
A large-gap uniform discharge is ignited by a coaxial dielectric barrier discharge and burns between a needle anode and a plate cathode under a low sustaining voltage by feeding with flowing argon. The basic aspects o...A large-gap uniform discharge is ignited by a coaxial dielectric barrier discharge and burns between a needle anode and a plate cathode under a low sustaining voltage by feeding with flowing argon. The basic aspects of the large-gap uniform discharge are investigated by optical and spectroscopic methods. From the discharge images, it can be found that this discharge has similar regions with glow discharge at low pressure except a plasma plume region. Light emission signals from the discharge indicate that the plasma column is invariant with time, while there are some stochastic pulses in the plasma plume region. The optical emission spectra scanning from 300 nm to 800 nm are used to calculate the excited electron temperature and vibrational temperature of the large-gap uniform discharge. It has been found that the excited electron temperature almost keeps constant and the vibrational temperature increases with increasing discharge current. Both of them decreases with increasing gas flow rate.展开更多
Large-gap nerve defects require nerve guide conduits(NGCs)for complete regeneration and muscle innervation.Many NGCs have been developed using various scaffold designs and tissue engineering strategies to promote axon...Large-gap nerve defects require nerve guide conduits(NGCs)for complete regeneration and muscle innervation.Many NGCs have been developed using various scaffold designs and tissue engineering strategies to promote axon regeneration.Still,most are tubular with inadequate pore sizes and lack surface cues for nutrient transport,cell attachment,and tissue infiltration.This study developed a porous spiral NGC to address these issues using a 3D-printed thermoplastic polyurethane(TPU)fiber lattice.The lattice was functionalized with poly(3-hydroxybutyrate-co-3-hydroxyvalerate)(PHBV)electrospun aligned(aPHBV)and randomly(rPHBV)oriented nanofibers to enhance cellular activity.TPU lattices were made with 25%,35%,and 50%infill densities to create scaffolds with varied mechanical compliance.The fabricated TPU/PHBV spiral conduits had significantly higher surface areas(25%TPU/PHBV:698.97 mm^(2),35%TPU/PHBV:500.06 mm^(2),50%TPU/PHBV:327.61 mm^(2))compared to commercially available nerve conduits like Neurolac™(205.26 mm^(2)).Aligned PHBV nanofibers showed excellent Schwann cell(RSC96)adhesion,proliferation,and neurogenic gene expression for all infill densities.Spiral TPU/PHBV conduits with 25%and 35%infill densities exhibited Young’s modulus values comparable to Neurotube®and ultimate tensile strength like acellular cadaveric human nerves.A 10 mm sciatic nerve defect in Wistar rats treated with TPU/aPHBV NGCs demonstrated muscle innervation and axon healing comparable to autografts over 4 months,as evaluated by gait analysis,functional recovery,and histology.The TPU/PHBV NGC developed in this study shows promise as a treatment for large-gap nerve defects.展开更多
基金Supported by the Science Foundation of Nanjing University of Posts and Telecommunications under Grant No NY215064the China Postdoctoral Science Foundation under Grant No 2015M581824the Jiangsu Post-doctoral Foundation under Grant No1501070B
文摘The searches for large-gap quantum spin Hall insulators are important for both practical and fundamental inter- ests. In this work, we present a theoretical observation of the two-dimensional fully fluorinated stanene （SnF） by means of density functional theory. Remarkably, a significant spin-orbit coupling is observed for the SnF monolayer in the valence band at the F point, with a considerable indirect band gap of 278 meV. The direct gap of the SnF monolayer is at the F point, which is slightly larger by as much as 381 meV. In addition, the elastic modulus of the SnF monolayer is about 20J/m^2, which is comparable with the in-plane stiffness of black phos- phorus monolayer along the x-direction （~28.94 J/m^2）. Finally, the optical properties of stanene, SnF monolayer and stanene/SnF bilayer are calculated, in which the stanene/SnF bilayer is supposed to be an attractive sunlight absorber.
基金supported by the National Natural Science Foundation of China(Grant Nos.10805013 and 51077035)the Funds for Distinguished Young Scientists of Hebei Province of China(Grant No.A2012201045)+4 种基金the Natural Science Foundation of Hebei Province of China(Grant No.A2011201132)the Department of Education for Outstanding Youth Project of China(Grant No.Y2011120)the Funds for Distinguished Young Scientists of Hebei University of China(Grant No.2010J02)the Doctor Program of Hebei University of China(Grant No.2012-241)the Youth Project of Hebei University of China(GrantNo.2011Q14)
文摘A large-gap uniform discharge is ignited by a coaxial dielectric barrier discharge and burns between a needle anode and a plate cathode under a low sustaining voltage by feeding with flowing argon. The basic aspects of the large-gap uniform discharge are investigated by optical and spectroscopic methods. From the discharge images, it can be found that this discharge has similar regions with glow discharge at low pressure except a plasma plume region. Light emission signals from the discharge indicate that the plasma column is invariant with time, while there are some stochastic pulses in the plasma plume region. The optical emission spectra scanning from 300 nm to 800 nm are used to calculate the excited electron temperature and vibrational temperature of the large-gap uniform discharge. It has been found that the excited electron temperature almost keeps constant and the vibrational temperature increases with increasing discharge current. Both of them decreases with increasing gas flow rate.
基金The authors wish to acknowledge Nano Mission,Department of Science&Technology(DST)(SR/NM/TP-83/2016(G))Prof.T.R.Rajagopalan R&D Cell of SASTRA Deemed University for financial and infrastructural support+4 种基金We also wish to acknowledge ATGC grant,Department of Biotechnology(DBT)(BT/ATGC/127/SP41147/2021)Adhoc funding,Indian Council of Medical Research(ICMR)(17x3/Adhoc/23/2022-ITR)DST SERB CRG(Exponential Technologies)grant(CRG/2021/007847)for financial supportfunding support provided by the National Institutes of Health(#R01NS134604,#R01EB034202,#R01AR078908,and#R01EB030060)the U.S.Army Medical Research Acquisition Activity(USAMRAA)through the CDMRP Peer-Reviewed Medical Research Program(Award No.W81XWH2010321,PR230581,and HT94252410137).
文摘Large-gap nerve defects require nerve guide conduits(NGCs)for complete regeneration and muscle innervation.Many NGCs have been developed using various scaffold designs and tissue engineering strategies to promote axon regeneration.Still,most are tubular with inadequate pore sizes and lack surface cues for nutrient transport,cell attachment,and tissue infiltration.This study developed a porous spiral NGC to address these issues using a 3D-printed thermoplastic polyurethane(TPU)fiber lattice.The lattice was functionalized with poly(3-hydroxybutyrate-co-3-hydroxyvalerate)(PHBV)electrospun aligned(aPHBV)and randomly(rPHBV)oriented nanofibers to enhance cellular activity.TPU lattices were made with 25%,35%,and 50%infill densities to create scaffolds with varied mechanical compliance.The fabricated TPU/PHBV spiral conduits had significantly higher surface areas(25%TPU/PHBV:698.97 mm^(2),35%TPU/PHBV:500.06 mm^(2),50%TPU/PHBV:327.61 mm^(2))compared to commercially available nerve conduits like Neurolac™(205.26 mm^(2)).Aligned PHBV nanofibers showed excellent Schwann cell(RSC96)adhesion,proliferation,and neurogenic gene expression for all infill densities.Spiral TPU/PHBV conduits with 25%and 35%infill densities exhibited Young’s modulus values comparable to Neurotube®and ultimate tensile strength like acellular cadaveric human nerves.A 10 mm sciatic nerve defect in Wistar rats treated with TPU/aPHBV NGCs demonstrated muscle innervation and axon healing comparable to autografts over 4 months,as evaluated by gait analysis,functional recovery,and histology.The TPU/PHBV NGC developed in this study shows promise as a treatment for large-gap nerve defects.
