多巴胺在聚L-半胱氨酸/多壁碳纳米管修饰电极上的电化学行为及其伏安测定

多巴胺;L-半胱氨酸;多壁碳纳米管;修饰电极     

High quality above 3-μm mid-infrared InGaAsSb/AIGaInAsSb multiple-quantum well grown by molecular beam epitaxy

The GaSb-based laser shows its superiority in the 3-4 ~tm wavelength range. However, for a quantum well （QW） laser structure of InGaAsSb/AIGaInAsSb multiple-quantum well （MQW） grown on GaSb, uniform content and high com- pressive strain in InGaAsSb/A1GaInAsSb are not easy to control. In this paper, the influences of the growth tempera- ture and compressive strain on the photoluminescence （PL） property of a 3.0μm lnGaAsSb/A1GaInAsSb MQW sample are analyzed to optimize the growth parameters. Comparisons among the PL spectra of the samples indicate that the Ino.485GaAso.184Sb/Alo.3Gao.45Ino.25Aso.22Sbo.78 MQW with 1.72% compressive strain grown at 460 ~C posseses the op- timum optical property. Moreover, the wavelength range of the MQW structure is extended to 3.83 μm by optimizing the parameters.     

碳包覆改性制备高倍率性能的锂离子电池正极材料LiNi1/3Co1/3Mn1/3O2

采用碳酸盐共沉淀-高温固相法制备了一系列表面碳包覆改性（w=1.0%,2.0%,3.0%）的LiNi_1/3Co_1/3Mn_1/3O₂正极材料,借助X射线衍射（XRD）分析、扫描电镜（SEM）、透射电镜（TEM）、电化学阻抗谱（EIS）和恒电流充放电测试等表征手段对材料的晶体结构、微观形貌和电化学性能进行了较系统的研究。结果表明,碳成功地包覆在了材料颗粒的表面,碳包覆改性后的材料具有良好的α-NaFeO₂结构（空间群为R3m）,且随着包碳量的增加,一次颗粒平均尺寸逐渐增大（从177 nm增至209 nm）。表面的无定形碳层可以提高材料的电子导电率,减少电极材料与电解液的副反应,故而碳包覆材料的电化学性能都有了一定程度提升。包覆碳量为2.0%的样品高倍率和长循环性能最好,在2.7~4.3 V,1C下循环100次后,容量保持率为93%;在0.1C、0.2C、0.5C、1C、3C、5C、10C和20C时的放电比容量分别为：155、148、145、138、127、116、104和96 mAh·g^-1。在超高倍率50C（9 A·g^-1）时,其放电比容量还能达到62 mAh·g^-1（原始LiNi_1/3Co_1/3Mn_1/3O₂材料仅为30 mAh·g^-1）,倍率性能十分优异。     

0.41 THz折叠波导慢波结构分析与设计

在0.14 THz,0.22 THz和0.34 THz折叠波导行波管研制的基础上,讨论了0.41 THz折叠波导行波管慢波结构设计与加工的可行性,分析研究了折叠波导慢波结构弯曲处直角弯曲与半圈弯曲、方形电子注通道与圆形电子注通道对色散特性、耦合阻抗、带宽、冷损耗和增益的影响。考虑了慢波结构中增加理想衰减器对该行波管带宽和增益的影响,得到了0.41 THz折叠波导行波管慢波结构的初步设计方案,为太赫兹折叠波导行波管的继续发展打下了一定基础。     

分段表面放电沉积效率研究

利用一种结构紧凑的分段表面放电辐射源模块，详细研究了在不同电压、电容、气压实验条件下回路等效电阻、等效电感及放电能量沉积效率的变化规律，利用四分幅相机拍摄获得了不同实验条件下的放电等离子体通道图像，分析讨论了放电等离子体运动对放电能量沉积效率的影响，提出了提高能量放电沉积效率的有效途径。     

带有控制输入扰动和死区的混沌系统自适应模糊控制

针对带有非线性输入和控制增益矩阵扰动的未知时变时滞混沌系统,提出了一种自适应模糊变结构控制方法.设计的控制器可以保证跟踪误差收敛到原点的可调邻域内,并且闭环系统所有信号有界.该方法对系统扰动的变化能保持较好的鲁棒性.最后以多卷波混沌系统为例的仿真实验进一步验证了该方法的有效性.     

High quality above 3-μm mid-infrared InGaAsSb/AlGaInAsSb multiple-quantum well grown by molecular beam epitaxy

The GaSb-based laser shows its superiority in the 3–4 μm wavelength range. However, for a quantum well(QW) laser structure of InGaAsSb/AlGaInAsSb multiple-quantum well(MQW) grown on GaSb, uniform content and high compressive strain in InGaAsSb/AlGaInAsSb are not easy to control. In this paper, the influences of the growth temperature and compressive strain on the photoluminescence(PL) property of a 3.0-μm InGaAsSb/AlGaInAsSb MQW sample are analyzed to optimize the growth parameters. Comparisons among the PL spectra of the samples indicate that the In0.485GaAs0.184Sb/Al0.3Ga0.45In0.25As0.22Sb0.78MQW with 1.72% compressive strain grown at 460 C posseses the optimum optical property. Moreover, the wavelength range of the MQW structure is extended to 3.83 μm by optimizing the parameters.     

Very long wavelength infrared focal plane arrays with 50% cutoff wavelength based on type-Ⅱ In As/GaSb superlattice

A very long wavelength infrared(VLWIR) focal plane array based on In As/Ga Sb type-Ⅱ super-lattices is demonstrated on a Ga Sb substrate. A hetero-structure photodiode was grown with a 50% cut-off wavelength of 15.2 μm, at 77 K.A 320×256 VLWIR focal plane array with this design was fabricated and characterized. The peak quantum efficiency without an antireflective coating was 25.74% at the reverse bias voltage of-20 mV, yielding a peak specific detectivity of 5.89×1010cm·Hz~(1/2)·W~(-1). The operability and the uniformity of response were 89% and 83.17%. The noise-equivalent temperature difference at 65 K exhibited a minimum at 21.4 mK, corresponding to an average value of 56.3 mK.     

基于ARM自主避障机器鱼设计

研究设计了基于ARM芯片和LINUX嵌入式系统具有自主避障功能的机器鱼。首先搭建了基于ARM芯片的硬件平台．然后对图像采集、图像显示和红外测距进行实现。通过红外传感器实现机器鱼的自主避障的功能。实验表明基于该方案设计的机器鱼能流畅地进行实时自主避障与图像显示。可以作为后续机器鱼的自主视觉功能开发的基础,提高了机器鱼的智能度。     

基于时空估计的冷像校正方法

冷像是影响制冷型红外探测器成像质量的重要因素。虽然可以通过非均匀校正技术进行去除,但当校正后的工作条件发生改变时,冷像的影响又会显现出来。根据冷像产生的机理以及频率特点,提出了一种基于时空估计的冷像校正算法。首先,通过使用小波分解与重构对原始图像进行冷像噪声空间域估计;然后,利用自适应时域低通滤波获得冷像噪声的时间域估计;最后,利用原始图像与获得的冷像估计噪声做差完成校正过程。使用仿真和实际的红外图像序列进行实验,结果表明所提算法能够有效地去除冷像噪声。