Non‐Lithographic Fabrication of All‐2D α‐MoTe2 Dual Gate Transistors

As one of the emerging new transition‐metal dichalcogenides materials, molybdenum ditelluride (α‐MoTe₂) is attracting much attention due to its optical and electrical properties. This study fabricates all‐2D MoTe₂‐based field effect transistors (FETs) on glass, using thin hexagonal boron nitride and thin graphene in consideration of good dielectric/channel interface and source/drain contacts, respectively. Distinguished from previous works, in this study, all 2D FETs with α‐MoTe₂ nanoflakes are dual‐gated for driving higher current. Moreover, for the present 2D dual gate FET fabrications on glass, all thermal annealing and lithography processes are intentionally exempted for fully non‐lithographic method using only van der Waal's forces. The dual‐gate MoTe₂ FET displays quite a high hole and electron mobility over ≈20 cm² V^?1 s^?1 along with ON/OFF ratio of ≈10⁵ in maximum as an ambipolar FET and also demonstrates high drain current of a few tens‐to‐hundred μA at a low operation voltage. It appears promising enough to drive organic light emitting diode pixels and NOR logic functions on glass.     

IPTV双模机顶盒终端技术在三网合一领域的应用

IPTV双模机顶盒作为广电双向交互业务开展的用户终端设备,其同时具备DVB-C与IP两种接入系统的方式。主要由软件和硬件两部分组成,整个硬件系统以高性能专用SOC SMP8635L为核心,辅以外围辅助芯片和电路所构成;软件部分则由嵌入式浏览器构成。随着三网融合业务和微电子技术的发展,IPTV机顶盒产品会越来越成熟,功能越来越强大。     

3G移动可视电话系统设计

介绍了3G移动可视电话的设计架构模式,基于Window CE操作系统,结合VTApp、3G-324M协议栈、音视频设备驱动、RIL和双端口RAM等相关模块,实现了可视电话这一复杂的多媒体应用系统的运行,描述了相关模块的工作原理与设计思路,并通过对呼出流程图加以介绍的方式,对可视电话系统的运行流程加以阐述。     

Hierarchical Ordered Dual‐Mesoporous Polypyrrole/Graphene Nanosheets as Bi‐Functional Active Materials for High‐Performance Planar Integrated System of Micro‐Supercapacitor and Gas Sensor

Planar integrated systems of micro‐supercapacitors (MSCs) and sensors are of profound importance for 3C electronics, but usually appear poor in compatibility due to the complex connections of device units with multiple mono‐functional materials. Herein, 2D hierarchical ordered dual‐mesoporous polypyrrole/graphene (DM‐PG) nanosheets are developed as bi‐functional active materials for a novel prototype planar integrated system of MSC and NH₃ sensor. Owing to effective coupling of conductive graphene and high‐sensitive pseudocapacitive polypyrrole, well‐defined dual‐mesopores of ≈7 and ≈18 nm, hierarchical mesoporous network, and large surface area of 112 m² g^?1, the resultant DM‐PG nanosheets exhibit extraordinary sensing response to NH₃ as low as 200 ppb, exceptional selectivity toward NH₃ that is much higher than other volatile organic compounds, and outstanding capacitance of 376 F g^?1 at 1 mV s^?1 for supercapacitors, simultaneously surpassing single‐mesoporous and non‐mesoporous counterparts. Importantly, the bi‐functional DM‐PG‐based MSC‐sensor integrated system represents rapid and stable response exposed to 10–40 ppm of NH₃ after only charging for 100 s, remarkable sensitivity of NH₃ detection that is close to DM‐PG‐based MSC‐free sensor, impressive flexibility with ≈82% of initial response value even at 180°, and enhanced overall compatibility, thereby holding great promise for ultrathin, miniaturized, body‐attachable, and portable detection of NH₃.     

Plasmonic Dual‐Enhancement and Precise Color Tuning of Gold Nanorod@SiO2 Coupled Core–Shell–Shell Upconversion Nanocrystals

The last decade has witnessed the remarkable research progress of lanthanide‐doped upconversion nanocrystals (UCNCs) at the forefront of promising applications. However, the future development and application of UCNCs are constrained greatly by their underlying shortcomings such as significant nonradiative processes, low quantum efficiency, and single emission colors. Here a hybrid plasmonic upconversion nanostructure consisting of a GNR@SiO₂ coupled with NaGdF₄:Yb³⁺,Nd³⁺@NaGdF₄:Yb³⁺,Er³⁺@NaGdF₄ core–shell–shell UCNCs is rationally designed and fabricated, which exhibits strongly enhanced UC fluorescence (up to 20 folds) and flexibly tunable UC colors. The experimental findings show that controlling the SiO₂ spacer thickness enables readily manipulating the intensity ratio of the Er³⁺ red, green, and blue emissions, thereby allowing us to achieve the emission color tuning from pale yellow to green upon excitation at 808 nm. Electrodynamic simulations reveal that the tunable UC colors are due to the interplay of plasmon‐mediated simultaneous excitation and emission enhancements in the Er³⁺ green emission yet only excitation enhancement in the blue and red emissions. The results not only provide an upfront experimental design for constructing hybrid plasmonic UC nanostructures with high efficiency and color tunability, but also deepen the understanding of the interaction mechanism between the Er³⁺ emissions and plasmon resonances in such complex hybrid nanostructure.     

基于指纹识别技术的双重身份鉴别系统实现

本文依据信息安全等级保护基本要求,利用指纹识别技术,设计了信息化应用的双重身份鉴别系统方案。方案通过建立指纹数据库,采集用户指纹信息并和账户关联,通过认证服务在用户登录时进行指纹认证实现双重身份鉴别。方案具有安全性高、适用面广、使用方便和抗抵赖等特点。     

双速度环在双马达直流调速系统中的应用

在雷达控制系统中,双速度环驱动系统应用于工程设计和产品中还为数不多,但实践已证明了他的可行性和独特的优越性。尤其在多马达驱动系统中,使用多速度环控制体制,可以使驱动系统的设计更简洁,生产、调试更方便,运用更灵活。从工程实际应用出发,提出了双马达直流驱动系统采用双速度环体制的必要性,进而对这种工作体制的特点,可能出现的问题及解决办法进行了分析和论述。     

基于对偶四元数的圆锥及划船误差补偿改进算法

为提高高动态环境下的对偶四元数捷联惯性导航算法解算精度,将梯形数字积分算法应用于圆锥和划船误差补偿算法中,改进了姿态和速度解算算法,提高了对偶四元数捷联惯性导航算法的解算精度。在单个采样周期内,利用前一时刻采集的陀螺角速率信号和当前时刻采集的陀螺角速率信号,通过梯形积分方式计算角增量进行圆锥误差补偿;利用前一时刻采集的加速度计信号和当前时刻的加速度计信号,通过梯形积分方式计算速度增量并结合同一时刻的角增量进行划船误差补偿。通过设计的多组动态模拟仿真航迹验证表明,当角速率和比力作为圆锥和划船误差补偿算法输入时,梯形积分算法的精度高于传统的矩形积分算法,且航迹的动态性越高,改进算法的性能优势越显著。同时,通过动态跑车实验结果的分析对比,进一步验证了该改进算法的实用性。     

红外双色探测研究

分析了红外双色探测的工作原理,计算了双色探测中等效比值与辐射源温度的关系,并与报道的实测结果进行了比较,提出了通过判断比值的大小来识别真实目标.     

变形对双相钢相变行为及组织的影响

利用Gleeble3500热模拟试验机,结合光学显微镜,研究双相钢在不同变形量和保温温度条件下的相变行为及组织演变规律。结果表明:变形量和保温温度对第二相的体积分数均有影响,随变形量的增加,保温温度的降低,第二相的体积分数增加。当冷却速度为25℃/s时,保温温度选择450～500℃,可以得到较为理想的组织。