A microchip interdigitated electrode with a sequential signal generator has been developed for traveling wave dielectrophoresis (twDEP) of biological cell suspensions. The electrode was fabricated on a microscope glas...A microchip interdigitated electrode with a sequential signal generator has been developed for traveling wave dielectrophoresis (twDEP) of biological cell suspensions. The electrode was fabricated on a microscope glass slide and coated with a 0.5 μm thickness of gold through a sputtering technique which was designed for large-scale inductions of cells rather than for individual cells as in previous versions of our device. As designed for a representative cell size of 10 μm, the electrode array was 50 μm in width to allow large numbers (>106) of cells to be processed. The sequential signal generator produces an arbitrary AC quadrature-phase to generate traveling electric field for a microchip interdigitated electrode. Each phase signal can be automatically altered and alternated with the other phases within interval time of 0.01-30 seconds (controlled by programming). We demonstrate the system could be used to estimate the dielectric properties of the yeast Saccharomyces cerivisiae TISTR 5088, the green alga Tetraselmis sp. and human red blood cells (HRBCs) through curve-fitting of dielectro- phoretic velocities and critical frequencies.展开更多
Hard carbon derived from bamboo for the anode material of sodium-ion batteries has a three-dimensional(3D) open framework structure and has naturally incorporated K-ions into its carbon structure,increasing the dinter...Hard carbon derived from bamboo for the anode material of sodium-ion batteries has a three-dimensional(3D) open framework structure and has naturally incorporated K-ions into its carbon structure,increasing the dinterlayer spacing of hard carbon materials for facilitating Na^(+) transport.In this work,bamboo-derived hard carbon was prepared via two carbonization temperatures at 700and 1000 ℃ for an hour and employed as an anode for sodium-ion batteries(SIB).X-ray diffraction(XRD) and Fourier transform(FT)-Raman spectroscopic results indicated the disordered structure with d-spacing(d_(002)) around0.36-0.37 nm,which is a benefit for sodium ion insertion/desertion.Herein,the composition between carbon-nanotube(CNT) and bamboo-derived hard carbon(BB) was synthesized by a ball mill with various contents of CNT(1 wt%,5 wt% and 10 wt%).At the optimal CNT content of 5 wt%,the sample exhibited excellent performance and outstanding stability.As the anode,the half-cell SIB using BB(700)w@5%CNT(with a carbonization temperature of700 ℃ and CNT loading of 5 wt%) delivered a high initial specific capacity of 268.9 mAh·g^(-1) at 0.1C and capacity retention of 78.6% after 500 cycles at 1.0C.The full cell SIB fabrication BB(700)w@5%CNT in combination with Na_(3)V_(2)(PO4)_(3) as the cathode demonstrated a high specific capacity of 127.6 mAh·g^(-1) at 0.2C with its capacitive retention remaining of 78% at 1.0C after 1000 cycles.The attained storage performance indicates that hard carbonCNT composite anode material enhanced the conductive path of electron transport and provided long-term cycling stability.The good electrochemical performance as well as the low cost and environment-friendliness of the bambooderived hard carbon proves its suitability for future sodium-ion batteries.展开更多
文摘A microchip interdigitated electrode with a sequential signal generator has been developed for traveling wave dielectrophoresis (twDEP) of biological cell suspensions. The electrode was fabricated on a microscope glass slide and coated with a 0.5 μm thickness of gold through a sputtering technique which was designed for large-scale inductions of cells rather than for individual cells as in previous versions of our device. As designed for a representative cell size of 10 μm, the electrode array was 50 μm in width to allow large numbers (>106) of cells to be processed. The sequential signal generator produces an arbitrary AC quadrature-phase to generate traveling electric field for a microchip interdigitated electrode. Each phase signal can be automatically altered and alternated with the other phases within interval time of 0.01-30 seconds (controlled by programming). We demonstrate the system could be used to estimate the dielectric properties of the yeast Saccharomyces cerivisiae TISTR 5088, the green alga Tetraselmis sp. and human red blood cells (HRBCs) through curve-fitting of dielectro- phoretic velocities and critical frequencies.
基金facilitated by Hideki Nakajima as the beamline manager of the Synchrotron Light Research Institute in Thailandreceived partial funding support from the NSRF via the Program Management Unit for the Human Resources & Institutional Development, Research, and Innovation (PMU-B)in the Industrial Postdoctoral Research Fellowship Program to support Thailand Strategic Industry (No.B01F640054) that was carried out as a part of the requirement for the Postdoctoral Fellowship Program of Dr. Sukanya Pothaya in NSTDA, Thailand。
文摘Hard carbon derived from bamboo for the anode material of sodium-ion batteries has a three-dimensional(3D) open framework structure and has naturally incorporated K-ions into its carbon structure,increasing the dinterlayer spacing of hard carbon materials for facilitating Na^(+) transport.In this work,bamboo-derived hard carbon was prepared via two carbonization temperatures at 700and 1000 ℃ for an hour and employed as an anode for sodium-ion batteries(SIB).X-ray diffraction(XRD) and Fourier transform(FT)-Raman spectroscopic results indicated the disordered structure with d-spacing(d_(002)) around0.36-0.37 nm,which is a benefit for sodium ion insertion/desertion.Herein,the composition between carbon-nanotube(CNT) and bamboo-derived hard carbon(BB) was synthesized by a ball mill with various contents of CNT(1 wt%,5 wt% and 10 wt%).At the optimal CNT content of 5 wt%,the sample exhibited excellent performance and outstanding stability.As the anode,the half-cell SIB using BB(700)w@5%CNT(with a carbonization temperature of700 ℃ and CNT loading of 5 wt%) delivered a high initial specific capacity of 268.9 mAh·g^(-1) at 0.1C and capacity retention of 78.6% after 500 cycles at 1.0C.The full cell SIB fabrication BB(700)w@5%CNT in combination with Na_(3)V_(2)(PO4)_(3) as the cathode demonstrated a high specific capacity of 127.6 mAh·g^(-1) at 0.2C with its capacitive retention remaining of 78% at 1.0C after 1000 cycles.The attained storage performance indicates that hard carbonCNT composite anode material enhanced the conductive path of electron transport and provided long-term cycling stability.The good electrochemical performance as well as the low cost and environment-friendliness of the bambooderived hard carbon proves its suitability for future sodium-ion batteries.
