In this communication,we report a synthetic approach to fabricate Y-junction Co nanowires and Y-junction Cu nanowires by AC electrodeposition using a hierarchically designed anodized aluminum oxide template.Morphology...In this communication,we report a synthetic approach to fabricate Y-junction Co nanowires and Y-junction Cu nanowires by AC electrodeposition using a hierarchically designed anodized aluminum oxide template.Morphology study showe that diameters of the stems and branches of the Y-junction nanowires were about 40 nm and 20 nm respectively.Structural analysis indicates that Co nanowires had a mixture of face-center-cubic and hexagonal-close-packed structures,whereas Cu nanowires had a face-center-cubic structure with a <110> texture.The Y-junction Co nanowires exhibited a longitudinal coercivity of 1300 Oe and remnant magnetization of 56%,which was affected by the growth direction and microstructure.The present method can be extended to other metallic systems and thus provides a simple and efficient way to fabricate Y-junction metal nanowires.展开更多
Droplets generation in Y-junctions and anti-Yjunctions microchannels are experimentally studied using a high speed digital microscopic system and numerical simulation.Geometric configuration of a microchannel,such as ...Droplets generation in Y-junctions and anti-Yjunctions microchannels are experimentally studied using a high speed digital microscopic system and numerical simulation.Geometric configuration of a microchannel,such as Y-angle（90°,135°,-90° and-135°）,channel depth and other factors have been taken into consideration.It is found that droplets generated in anti-Y-junctions have a smaller size and a shorter generation cycle compared with those in Yjunctions under the same experimental conditions.Through observing the internal velocity field,the vortex appearing in continuous phase in anti-Y-junctions is one of the key factors for the difference of droplet size and generation cycle.It is found that droplet size is bigger and generation cycle is longer when the absolute angle value of the intersection between the continuous and the dispersed phases（i.e.,the angle between the main channel and the continuous phase or the dispersed phase channel） increases.The droplet＇s size is influenced by the Y-angle,which varies with the channel depth in Y-junctions.The Y-angle has a positive effect on the droplet generation cycle,but a smaller height-width ratio will enhance the impact of a continuous and dispersed phase＇s intersection angle on the droplet generation cycle in Y-junctions microchannels.展开更多
The silicon-on-insulator(SOI) 1 × 2 Y-junction optical waveguide switch has been proposed and fabricated, which is based on the large cross-ction single--mode rib waveguide condition, the waveguide--vanishing eff...The silicon-on-insulator(SOI) 1 × 2 Y-junction optical waveguide switch has been proposed and fabricated, which is based on the large cross-ction single--mode rib waveguide condition, the waveguide--vanishing effect and the free-carrier plasma dispersion effect. The SOI switch utilizes silicon and silicon dioxide thermal bonding and back--polishing. The insertion loss and extinction ratio of the device are measured to be less than 4. 78 dB and 20. 8dB respectively at a wavelength of 1. 3pm and an injection current of 45mA. The response time is about 160us.展开更多
Y-shaped structure was synthesized by ethanol catalytic combustion(ECC) technique on the copper plate substrate, without directly seeding catalyst into the flame. The as-grown Y-junction carbon nanofibres were investi...Y-shaped structure was synthesized by ethanol catalytic combustion(ECC) technique on the copper plate substrate, without directly seeding catalyst into the flame. The as-grown Y-junction carbon nanofibres were investigated by transmission electron microscopy (TEM). The very common laboratory ethanol burner was used for synthesizing carbon nanofibres. Two kinds of the catalyst precursor, which are iron nitrate (Fe(NO3)3) and nickel nitrate (Ni(NO3)2), were respectively employed to assist the formation of Y-junction carbon nanofibres. TEM analysis confirm the formation of Y-junction in the coiled and noncoiled carbon nanofibres. The type of the catalyst is found to be crucial to grow different Y-junction carbon nanofibres. Different Y-shaped structure may possess different mechanical and electronic properties. These three-terminal nanofibres provide the nanoelectronics community with a novel material for the development of molecular-scale electronic devices.展开更多
The silicon-on-insulator(SOI) 1×2 Y-junction optical waveguide switch has been proposed and fabricated,which is based on the large cross-section single-mode rib waveguide condition,the waveguide-vanishing effect ...The silicon-on-insulator(SOI) 1×2 Y-junction optical waveguide switch has been proposed and fabricated,which is based on the large cross-section single-mode rib waveguide condition,the waveguide-vanishing effect and the free-carrier plasma dispersion effect.In the switch,the SOI technique utilizes silicon and silicon dioxide thermal bonding and back-polishing.The insertion loss and extinction ratio of the device are measured to be less than 4.78 dB and 20.8 dB respectively at a wavelength of 1.3 μm and an injection current of 45 mA.Response time is about 160 ns.展开更多
基金financially supported partially by a NSF award CMMI-0825990
文摘In this communication,we report a synthetic approach to fabricate Y-junction Co nanowires and Y-junction Cu nanowires by AC electrodeposition using a hierarchically designed anodized aluminum oxide template.Morphology study showe that diameters of the stems and branches of the Y-junction nanowires were about 40 nm and 20 nm respectively.Structural analysis indicates that Co nanowires had a mixture of face-center-cubic and hexagonal-close-packed structures,whereas Cu nanowires had a face-center-cubic structure with a <110> texture.The Y-junction Co nanowires exhibited a longitudinal coercivity of 1300 Oe and remnant magnetization of 56%,which was affected by the growth direction and microstructure.The present method can be extended to other metallic systems and thus provides a simple and efficient way to fabricate Y-junction metal nanowires.
基金supported by the National Natural Science Foundation of China(Grants 11072011 and 11002007)
文摘Droplets generation in Y-junctions and anti-Yjunctions microchannels are experimentally studied using a high speed digital microscopic system and numerical simulation.Geometric configuration of a microchannel,such as Y-angle（90°,135°,-90° and-135°）,channel depth and other factors have been taken into consideration.It is found that droplets generated in anti-Y-junctions have a smaller size and a shorter generation cycle compared with those in Yjunctions under the same experimental conditions.Through observing the internal velocity field,the vortex appearing in continuous phase in anti-Y-junctions is one of the key factors for the difference of droplet size and generation cycle.It is found that droplet size is bigger and generation cycle is longer when the absolute angle value of the intersection between the continuous and the dispersed phases（i.e.,the angle between the main channel and the continuous phase or the dispersed phase channel） increases.The droplet＇s size is influenced by the Y-angle,which varies with the channel depth in Y-junctions.The Y-angle has a positive effect on the droplet generation cycle,but a smaller height-width ratio will enhance the impact of a continuous and dispersed phase＇s intersection angle on the droplet generation cycle in Y-junctions microchannels.
文摘The silicon-on-insulator(SOI) 1 × 2 Y-junction optical waveguide switch has been proposed and fabricated, which is based on the large cross-ction single--mode rib waveguide condition, the waveguide--vanishing effect and the free-carrier plasma dispersion effect. The SOI switch utilizes silicon and silicon dioxide thermal bonding and back--polishing. The insertion loss and extinction ratio of the device are measured to be less than 4. 78 dB and 20. 8dB respectively at a wavelength of 1. 3pm and an injection current of 45mA. The response time is about 160us.
基金Project(KM200510772013) supported by Beijing City Education Committee Science and Technology Development Program Project(2005-2007) supported by Beijing City Education Committee Academic Innovative Team Program
文摘Y-shaped structure was synthesized by ethanol catalytic combustion(ECC) technique on the copper plate substrate, without directly seeding catalyst into the flame. The as-grown Y-junction carbon nanofibres were investigated by transmission electron microscopy (TEM). The very common laboratory ethanol burner was used for synthesizing carbon nanofibres. Two kinds of the catalyst precursor, which are iron nitrate (Fe(NO3)3) and nickel nitrate (Ni(NO3)2), were respectively employed to assist the formation of Y-junction carbon nanofibres. TEM analysis confirm the formation of Y-junction in the coiled and noncoiled carbon nanofibres. The type of the catalyst is found to be crucial to grow different Y-junction carbon nanofibres. Different Y-shaped structure may possess different mechanical and electronic properties. These three-terminal nanofibres provide the nanoelectronics community with a novel material for the development of molecular-scale electronic devices.
文摘The silicon-on-insulator(SOI) 1×2 Y-junction optical waveguide switch has been proposed and fabricated,which is based on the large cross-section single-mode rib waveguide condition,the waveguide-vanishing effect and the free-carrier plasma dispersion effect.In the switch,the SOI technique utilizes silicon and silicon dioxide thermal bonding and back-polishing.The insertion loss and extinction ratio of the device are measured to be less than 4.78 dB and 20.8 dB respectively at a wavelength of 1.3 μm and an injection current of 45 mA.Response time is about 160 ns.
