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Tailored design/fabrication of high-rate electrodes is of great importance for construction of high-power lithium ion batteries (LIBs). In this work, we report a powerful strategy for fabrication of binder-free Li4Ti5O12/N-doped carbon (LTO/N-C) nanotube arrays via an atomic-layer-deposition (ALD)-lithiation plus chemical polymerization method. A thin N-C layer of 2–3 nm is homogeneously coated on the surface of LTO nanotubes of 400–450 nm forming high-quality LTO/N-C nanotube arrays with high electrical conductivity and large porosity. Due to the unique composite nanotube array architecture, the designed LTO/N-C nanotube arrays exhibit noticeable high-rate performance with a higher specific capacity (153 mA h g−1 at 5C), and better cycling performance (130 mA h g−1 at 40C after 1600 cycles) than the unmodified LTO nanotube arrays. The synergistic combination of the nanotube structure and N-C coating is favorable for fast ion/electron transfer, leading to reinforced high-rate Li ion storage. Our work reveals a new way for the synthesis of advanced electrodes for application in high-power LIBs.

采用水热合成技术, 以盐酸、去离子水和钛酸丁酯为反应前驱物, 直接在透明导电玻璃(FTO)衬底上合成了具有金红石结构的TiO 2 纳米线束阵列。通过改变反应前驱物中钛酸丁酯的添加量, 实现了对TiO 2 纳米线束阵列密度的调控。以TiO 2 纳米线束阵列为光阳极、CdS为敏化剂, 组装了量子点敏化太阳能电池器件, 并研究了纳米线束阵列的密度对电池光伏性能的影响。结果表明: 纳米线的密度过高或过低均不利于电池光伏性能的提高。纳米线的优化密度为11.8×10 6 /mm 2 , 此时电池的光电转换效率达到了0.947%。

The copper-indium-gallium (CIG) metallic precursors with different stacking type (A: CuGa/CuIn/CuGa/glass and B: CuInGa/CuIn/CuInGa/glass) were prepared onto glass substrates by magnetron sputtering method. In order to prepare Cu(In1−xGax)Se2 (CIGS) thin films, the CIG precursors were then selenized with solid Se powder using a three-step reaction temperature profile. The influence of stacking type in precursors on structure, composition, morphology and electrical properties of the CIGS films is investigated by X-ray diffraction, energy dispersive spectrometer, scanning electron microscope and Hall effect measurement. The results reveal that the stacking type of the precursor has a strong influence on composition, morphology and properties of the CIGS thin films. The atomic ratios of Cu/(In+Ga)/Se of the CIGS films A and B are 1.61:1:2.11 and 1.39:1:2.04, respectively. The better quality CIGS thin films can be obtained through selenization of metallic precursor of CuInGa/CuIn/CuInGa/glass. The CIGS films are p-type semiconductor material. The hole concentration, resistivity and hole mobility of the CIGS thin films is 2.51 × 1017 cm−3, 3.11 × 104 Ω cm and 19.8 cm2 V−1 s−1, respectively.

CdS thin films were prepared by chemical bath deposition (CBD) at different ammonia concentration and different temperature using cadmium chloride hydrate, thiourea, ammonium chloride, ammonia and deionized water as precursors. The morphology structure and the optical properties of CdS thin films were characterized by scanning electron microscope (SEM), ultraviolet-visible spectra and spectroscopic ellipsometry. The results indicated that CdS thin film could be grown when ammonia concentration at the range of 0.4-1.0 mol /L and in the temperature range of 50 °C -80 °C. Within 600-980 nm wavelength，the average value of the refractive index was found to be 1.70 and the extinction coefficient was less than 0.08.

The ZnSxSe1−x thin films were prepared by chemical bath deposition technique on glass substrates. The composition ‘x’ was varied from 0 to 1 by changing the concentration of thiourea and sodium selenosulphate in the precursors. The morphology, structural and optical properties of the ZnSxSe1−x thin films were characterized by energy dispersive spectrometer, scanning electron microscopy, X-ray diffraction and UV-Vis spectrophotometer. The results reveal that the ZnSxSe1−x films are cubic zinc blende structure for x = 0, 0.19, 0.25, and amorphous for x = 0.75, 1. The optical band gap of the ZnSxSe1−x films increase from 2.88 to 3.76 eV when the value of ‘x’ increases from 0 to 1. The growth mechanism of the ZnSxSe1–x films was discussed.

This paper presents a two-dimensional movement and the one-dimensional rotating 3 DOF robot that can be used to pick up, delivery and place riveting column, thin axis (referred to as riveting column) and other parts, forming the assembly systems of riveting of sheet metal. In addition to the robot, the system also has moving table, clamp, a number of riveting column station and spin riveter etc. Moving table is equipped with the clamp, it can move in the X and Y directions, respectively. The clamp that fixed the sheet metal work-piece can move in Z-direction, which make it easy for assembling the riveting axis into the riveting holes on the work-piece. Robot can move along the Y axis and swing around the Z axis, make the nozzle that is in the end of manipulator move between riveting column stations and spin riveter, which pick up and place the riveting column. A number of riveting column station is used for store riveting column and sorting them. Spin riveter rotates while moving along the Z axis at the same time, by pressure and rotational force it completes the column riveting on sheet metal parts.

CdS thin films were prepared by chemical bath deposition technique using the precursors of SC(NH2)2, CdCl2, NH4Cl, NH3·H2O and deionized water. The obtained thin films were characterized by scanning electron microscopy, X-ray diffraction, energy dispersive spectrometer, UV–VIS specrophotometry and photoluminescence spectroscopy. The morphology, structural and optical properties of CdS thin films were investigated as a function of ammonia concentration and S/Cd molar ratios in precursors. The results reveal that morphology of CdS films change from flake like into spherical particle like, crystal structure from wurtzite structure to zinc blende structure, S/Cd atom ratios in CdS thin films increase and optical band gap E g decrease with increasing ammonia concentration in precursors. The room temperature photoluminescence spectrum of CdS thin films shows a strong peak at about 500 nm and a weak peak at about 675 nm.

ZnO nanowires with the diameters ranging from 20 to 40 nm and lengths in the range 3-5 μm were synthesized on ITO coated glass substrate by a low temperature (80 °C) solution method. The average aspect ratio (h/r) reached 150. Owing to the van der waals force the neighborly nanowires close up to form tower-like ZnO bundles. The field emission of the ZnO bundles shows a turn-on field of 7.1 V/μm at a current density of 10 μA/cm2. The threshold field is 11.3 V/μm at a current density of 10 mA/cm2. The good field emission performance is attributed to the high aspect ratio and tower-like shape.

采用水热合成技术, 以盐酸、去离子水和钛酸丁酯为反应前驱物, 在透明导电玻璃(FTO)衬底上合成TiO 2 纳米线束阵列. 采用X射线衍射(XRD)、扫描电子显微镜(SEM)和高分辨透射电镜(TEM)对其结构和形貌进行了分析. 结果表明: 在FTO衬底上形成了垂直排列的具有金红石结构的单晶TiO 2 纳米线束阵列, TiO 2 纳米线束由直径4~6nm的几十条纳米线聚集在一起, 形成宽度约110~210nm、长度约3?m的四方柱状结构. 研究了以TiO 2 纳米线束阵列为光阳极制备的染料敏化太阳能电池的光电性能, 其开路电压为0.72V, 短路电流密度为2.9mA/cm 2 , 填充因子为0.42, 转换效率为0.88%.

Electromagnetic interference effects in the bipolar voltage comparator was investigated in this paper. By using of bulk current injection (BCI), the coupling current stimulated by high power electromagnetic pulse was simulated. The experimental results shown that the aberrations such as pulse deriving and pulse width altering will come into being in the output waveforms of LM139 after current injection respectively. Furthermore, the coupling effect of pulse deriving and pulse width broadening were observed simultaneously in the higher level current injections.

The electromagnetic interference effects in the μA741 operational amplifier circuit were investigated in this paper. Through the using of pulse injection, the output characteristics of μA741 were simulated by considering of EMI effects. Through sensitivity and smoke analysis, the simulation results shown that the differential input stage and the intermediate amplifying stage are the most sensitive and vulnerable function model in the μA741 circuits to EMI effects.

Significant field emission has been observed from thin (< 1000A) amorphous-carbon-nitride (a-CN) films. X-ray photoelectron spectroscopy, infrared spectrometry, and UV-visible optical absorption spectrometry have been used to characterize the films. The field emission properties of the thin film have been studied by using a transparent anode imaging system. It is proposed that this class of films should be studied as candidates of coating material for cold cathode emitter, in order for one to benefit from their very high thermal conductivity and super hardness.

Microwave absorption properties of Mn- and Ni-doped zinc oxides were assessed in this study. Samples were prepared by the decomposition of acetate solid solutions. By changing the concentration of dopant ions in the reaction solutions, zinc oxides with different amounts of dopant were obtained. The morphologies, chemical compositions, and structures of the samples were investigated by scanning electron microscopy, energy dispersive x-ray spectroscopy, and x-ray powder diffraction. Electromagnetic characteristics of the doped samples were assessed by vector network analysis at a frequency range of 2–16 GHz. Both the real and imaginary parts of the complex permittivity decreased as Mn or Ni concentration increased. Results indicate that, compared with pure ZnO, Mn- and Ni-doped zinc oxides exhibit excellent microwave absorption properties. The highest level of microwave absorption observed was 80.7 dB at a frequency of 9.8 GHz, and the best frequency bandwidth was 8.6 GHz at reflection loss values below −10 dB.