Flexible supercapacitor electrodes with high mass loading are crucial for obtaining favorable electrochemical performance but still challenging due to sluggish electron and ion transport.Herein,rationally designed CNT...Flexible supercapacitor electrodes with high mass loading are crucial for obtaining favorable electrochemical performance but still challenging due to sluggish electron and ion transport.Herein,rationally designed CNT/MnO2/graphene-grafted carbon cloth electrodes are prepared by a“graft-deposit-coat”strategy.Due to the large surface area and good conductivity,graphene grafted on carbon cloth offers additional surface areas for the uniform deposition of MnO2(9.1 mg cm?2)and facilitates charge transfer.Meanwhile,the nanostructured MnO2 provides abundant electroactive sites and short ion transport distance,and CNT coated on MnO2 acts as interconnected conductive“highways”to accelerate the electron transport,significantly improving redox reaction kinetics.Benefiting from high mass loading of electroactive materials,favorable conductivity,and a porous structure,the electrode achieves large areal capacitances without compromising rate capability.The assembled asymmetric supercapacitor demonstrates a wide working voltage(2.2 V)and high energy density of 10.18 mWh cm?3.展开更多
The proportion of non-tuberculous mycobacteria to Mycobacterium tuberculosis cultivated in the laboratory has been recently increasing. Numerous skin and soft tissue infections have been reported, while osteomyelitis ...The proportion of non-tuberculous mycobacteria to Mycobacterium tuberculosis cultivated in the laboratory has been recently increasing. Numerous skin and soft tissue infections have been reported, while osteomyelitis is reported very rarely. A delayed diagnosis can cause a wide range of bone destruction and joint contracture, which highlights the importance of early recognition of osteomyelitis. Here we report a case of ankle osteomyelitis caused by Mycobacterium abscessus and treatment failure due to delayed diagnosis.展开更多
It is well known that the increase of necrotic core in previous atherosclerotic coronary artery disease is one of the conditions of vulnerable plaque. However, it is not known how fast necrotic core could decrease in ...It is well known that the increase of necrotic core in previous atherosclerotic coronary artery disease is one of the conditions of vulnerable plaque. However, it is not known how fast necrotic core could decrease in a vulnerable plaque. We had 2 patients who had suffered from acute myocardial infarction and had large amount of necrotic core in their culprit lesions at baseline, which decreased markedly within 7 days. Also, they were clinically stable and asymptomatic over 1 year follow-up. It is first report to show mar-kedly decrease of necrotic core amount within only 7 days in culprit lesions of 2 cases of acute myocardial infarction with angiographically minimal lesions.展开更多
Owing to the tremendous demands for high-resolution pixel-scale thin lenses in displays,we developed a graphenebased ultrathin square subpixel lens(USSL)capable of electrically tuneable focusing(ETF)with a performance...Owing to the tremendous demands for high-resolution pixel-scale thin lenses in displays,we developed a graphenebased ultrathin square subpixel lens(USSL)capable of electrically tuneable focusing(ETF)with a performance competitive with that of a typical mechanical refractive lens.The fringe field due to a voltage bias in the graphene proves that our ETF-USSL can focus light onto a single point regardless of the wavelength of the visible light—by controlling the carriers at the Dirac point using radially patterned graphene layers,the focal length of the planar structure can be adjusted without changing the curvature or position of the lens.A high focusing efficiency of over 60% at a visible wavelength of 405 nm was achieved with a lens thickness of <13 nm,and a change of 19.42% in the focal length with a 9% increase in transmission was exhibited under a driving voltage.This design is first presented as an ETF-USSL that can be controlled in pixel units of flat panel displays for visible light.It can be easily applied as an add-on to high resolution,slim displays and provides a new direction for the application of multifunctional autostereoscopic displays.展开更多
We demonstrate the dipole-assisted carrier transport properties of bis(trifluoromethane)sulfonamide(TFSI)-treated O-ReS_(2) field-effect transistors.Pristine ReS_(2) was compared with defect-mediated ReS_(2) to confir...We demonstrate the dipole-assisted carrier transport properties of bis(trifluoromethane)sulfonamide(TFSI)-treated O-ReS_(2) field-effect transistors.Pristine ReS_(2) was compared with defect-mediated ReS_(2) to confirm whether the presence of defects on the interface enhances the interaction between O-ReS_(2) and TFSI molecules.Prior to the experiment,density functional theory(DFT)calculation was performed,and the result indicated that the charge transfer between TFSI and O-ReS_(2) is more sensitive to external electric fields than that between TFSI and pristine ReS_(2).After TFSI treatment,the drain current of O-ReS_(2) FET was significantly increased up to 1,113.4 times except in the range of−0.32–0.76 V owing to Schottky barrier modulation from dipole polarization of TFSI molecules,contrary to a significant degradation in device performance in pristine ReS_(2) FET.Moreover,in the treated O-ReS_(2) device,the dipole direction was highly influenced by the voltage sweep direction,generating a significant area of hysteresis in I–V and transfer characteristics,which was further verified by the surface potential result.Furthermore,the dipole state was enhanced according to the wavelength of the light source and photocurrent.These results indicate that TFSI-treated ReS_(2) FET has large potential for use as next-generation memristor,memory,and photodetector.展开更多
Quantum dot light-emitting diodes(QD-LEDs)are considered as competitive candidate for next-generation displays or lightings.Recent advances in the synthesis of core/shell quantum dots(QDs)and tailoring procedures for ...Quantum dot light-emitting diodes(QD-LEDs)are considered as competitive candidate for next-generation displays or lightings.Recent advances in the synthesis of core/shell quantum dots(QDs)and tailoring procedures for achieving their high quantum yield have facilitated the emergence of high-performance QD-LEDs.Meanwhile,the charge-carrier dynamics in QD-LED devices,which constitutes the remaining core research area for further improvement of QD-LEDs,is,however,poorly understood yet.Here,we propose a charge transport model in which the charge-carrier dynamics in QD-LEDs are comprehensively described by computer simulations.The charge-carrier injection is modelled by the carrier-capturing process,while the effect of electric fields at their interfaces is considered.The simulated electro-optical characteristics of QD-LEDs,such as the luminance,current density and external quantum efficiency(EQE)curves with varying voltages,show excellent agreement with experiments.Therefore,our computational method proposed here provides a useful means for designing and optimising high-performance QD-LED devices.展开更多
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF2018R1D1A1B07051249)Nano Material Technology Development Program(NRF-2015M3A7B6027970)of MSIP/NRF and Center for Integrated Smart Sensors funded by the Ministry of Science,ICTFuture Planning,Republic of Korea,as Global Frontier Project(CISS-2012M3A6A6054186).
文摘Flexible supercapacitor electrodes with high mass loading are crucial for obtaining favorable electrochemical performance but still challenging due to sluggish electron and ion transport.Herein,rationally designed CNT/MnO2/graphene-grafted carbon cloth electrodes are prepared by a“graft-deposit-coat”strategy.Due to the large surface area and good conductivity,graphene grafted on carbon cloth offers additional surface areas for the uniform deposition of MnO2(9.1 mg cm?2)and facilitates charge transfer.Meanwhile,the nanostructured MnO2 provides abundant electroactive sites and short ion transport distance,and CNT coated on MnO2 acts as interconnected conductive“highways”to accelerate the electron transport,significantly improving redox reaction kinetics.Benefiting from high mass loading of electroactive materials,favorable conductivity,and a porous structure,the electrode achieves large areal capacitances without compromising rate capability.The assembled asymmetric supercapacitor demonstrates a wide working voltage(2.2 V)and high energy density of 10.18 mWh cm?3.
文摘The proportion of non-tuberculous mycobacteria to Mycobacterium tuberculosis cultivated in the laboratory has been recently increasing. Numerous skin and soft tissue infections have been reported, while osteomyelitis is reported very rarely. A delayed diagnosis can cause a wide range of bone destruction and joint contracture, which highlights the importance of early recognition of osteomyelitis. Here we report a case of ankle osteomyelitis caused by Mycobacterium abscessus and treatment failure due to delayed diagnosis.
文摘It is well known that the increase of necrotic core in previous atherosclerotic coronary artery disease is one of the conditions of vulnerable plaque. However, it is not known how fast necrotic core could decrease in a vulnerable plaque. We had 2 patients who had suffered from acute myocardial infarction and had large amount of necrotic core in their culprit lesions at baseline, which decreased markedly within 7 days. Also, they were clinically stable and asymptomatic over 1 year follow-up. It is first report to show mar-kedly decrease of necrotic core amount within only 7 days in culprit lesions of 2 cases of acute myocardial infarction with angiographically minimal lesions.
基金supported by Nano·Material Technology Development Program(NRF-2017M3A7B4041987)the Korean Government(MSIP-2015R1A5A1037668)through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT,and Future Planning.
文摘Owing to the tremendous demands for high-resolution pixel-scale thin lenses in displays,we developed a graphenebased ultrathin square subpixel lens(USSL)capable of electrically tuneable focusing(ETF)with a performance competitive with that of a typical mechanical refractive lens.The fringe field due to a voltage bias in the graphene proves that our ETF-USSL can focus light onto a single point regardless of the wavelength of the visible light—by controlling the carriers at the Dirac point using radially patterned graphene layers,the focal length of the planar structure can be adjusted without changing the curvature or position of the lens.A high focusing efficiency of over 60% at a visible wavelength of 405 nm was achieved with a lens thickness of <13 nm,and a change of 19.42% in the focal length with a 9% increase in transmission was exhibited under a driving voltage.This design is first presented as an ETF-USSL that can be controlled in pixel units of flat panel displays for visible light.It can be easily applied as an add-on to high resolution,slim displays and provides a new direction for the application of multifunctional autostereoscopic displays.
基金This work was supported by the national research foundation of Korea(NRF)grant funded by the Korea government(MIST)(Nos.NRF-2019R1A2C2090443,NRF-2017M3A7B4041987,NRF-2020M3F6A1081009,and NRF-2017M1A3A3A02015033)Korea Electric Power Corporation.(Grant No.R19XO01-23).
文摘We demonstrate the dipole-assisted carrier transport properties of bis(trifluoromethane)sulfonamide(TFSI)-treated O-ReS_(2) field-effect transistors.Pristine ReS_(2) was compared with defect-mediated ReS_(2) to confirm whether the presence of defects on the interface enhances the interaction between O-ReS_(2) and TFSI molecules.Prior to the experiment,density functional theory(DFT)calculation was performed,and the result indicated that the charge transfer between TFSI and O-ReS_(2) is more sensitive to external electric fields than that between TFSI and pristine ReS_(2).After TFSI treatment,the drain current of O-ReS_(2) FET was significantly increased up to 1,113.4 times except in the range of−0.32–0.76 V owing to Schottky barrier modulation from dipole polarization of TFSI molecules,contrary to a significant degradation in device performance in pristine ReS_(2) FET.Moreover,in the treated O-ReS_(2) device,the dipole direction was highly influenced by the voltage sweep direction,generating a significant area of hysteresis in I–V and transfer characteristics,which was further verified by the surface potential result.Furthermore,the dipole state was enhanced according to the wavelength of the light source and photocurrent.These results indicate that TFSI-treated ReS_(2) FET has large potential for use as next-generation memristor,memory,and photodetector.
基金This research was supported by the European Union under H2020 grant agreement No 685758‘1D-NEON’by the Engineering and Physical Sciences Research Council(EPSRC)project EP/P027628/1‘Smart Flexible Quantum Dot Lighting’.
文摘Quantum dot light-emitting diodes(QD-LEDs)are considered as competitive candidate for next-generation displays or lightings.Recent advances in the synthesis of core/shell quantum dots(QDs)and tailoring procedures for achieving their high quantum yield have facilitated the emergence of high-performance QD-LEDs.Meanwhile,the charge-carrier dynamics in QD-LED devices,which constitutes the remaining core research area for further improvement of QD-LEDs,is,however,poorly understood yet.Here,we propose a charge transport model in which the charge-carrier dynamics in QD-LEDs are comprehensively described by computer simulations.The charge-carrier injection is modelled by the carrier-capturing process,while the effect of electric fields at their interfaces is considered.The simulated electro-optical characteristics of QD-LEDs,such as the luminance,current density and external quantum efficiency(EQE)curves with varying voltages,show excellent agreement with experiments.Therefore,our computational method proposed here provides a useful means for designing and optimising high-performance QD-LED devices.