2D/2D 1T‐MoS2/Ti3C2 MXene Heterostructure with Excellent Supercapacitor Performance

2D/2D heterostructures can combine the collective advantages of each 2D material and even show improved properties from synergistic effects. 2D Transition metal carbide Ti₃C₂ MXene and 2D 1T‐MoS₂ have emerged as attractive prototypes in electrochemistry due to their rich properties. Construction of these two 2D materials, as well as investigation about synergistic effects, is absent due to the instability of 1T‐MoS₂. Here, 3D interconnected networks of 1T‐MoS₂/Ti₃C₂ MXene heterostructure are constructed by magneto‐hydrothermal synthesis, and the electrochemical storage mechanisms are investigated. Improved extra capacitance is observed due to enlarged ion storage space from a synergistically interplayed effect in 3D interconnected networks. Outstanding rate performance is realized because of ultrafast electron transport originating from Ti₃C₂ MXene. This work provides an archetype to realize excellent electrochemical properties in 2D/2D heterostructures.     

光纤激光轧辊毛化工艺参数研究

针对CO₂激光器和YAG激光器的种种不足,采用光纤激光毛化柔性工作站,对轧辊表面进行了不同尺寸和分布的毛化点彤貌加工。分析了光纤激光功率、脉冲频率、脉冲宽度、扫描速度、离焦量等工艺参数对毛化点形貌的影响。结果表明:通过合理匹配毛化工艺参数,能够得到精确可控的轧辊毛化形貌和满足生产要求的粗糙度,也可以实现相对无序的毛化点排列。     

基于某型投放装置的通用性测试软件设计

以某型投放装置测试软件的设计为背景,考虑到多种测试仪的测试任务的共性与特点,提出了软硬件相结合的的通用化设计方法;描述了其流程化、自动化、层次化的测试方式;对其各部分功能和通用性进行详细介绍;经过测试和使用,该软件平台通用性能好,操作简单,其通用性对各类测试系统的设计和发展有着重要的意义。     

面向对象的舰船红外特征动态仿真

讨论了基于UML的舰船红外特征动态模拟,通过采用面对对象方法的技术,编制了舰船红外特征模拟软件,得到了较为满意的计算结果.这对增强舰船隐蔽性、保密性、生存能力和红外对抗能力都有重要意义;另外,对舰船的红外隐身设计也有一定的指导意义.     

Charge‐Transport Behavior in Aligned Carbon Nanotubes: A Quantum‐Chemical Investigation

Correlated quantum‐chemical calculations are applied to analyze the amplitude of the electronic‐transfer integrals that describe charge transport in interacting carbon nanotubes (CNTs) by investigating the influences of: i) the relative positions of the CNTs, ii) the size of the CNTs, and iii) their chemical impurities. Our results indicate that the mobility of the charge carrier is extremely sensitive to the molecular packing and the presence of chemical impurities. The largest splitting for the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels is in the case of perfectly cofacial conformations where hexagons face hexagons in the dimer structure. We found that the diameter of the CNT determines the type of transporting carrier: for CNTs with large diameters hole transport dominates, while for thin CNTs electron transport dominates. In general, the carrier mobility for the perfect CNTs (n ≥ 3) is less pronounced than that of C₆₀ due to their relatively small strain. B‐ and N‐doped CNTs exhibit considerably larger mobilities owing to the possibility of metallic behavior. These results provide a plausible explanation for the high mobility found experimentally in a field‐effect transistor (FET) made from a large‐area, well‐aligned CNT array. In addition, these hole‐rich and electron‐rich dopants imply potential applications in nanoelectronics.     

一种用于开关电容电路的高性能运算放大器

设计了一种高性能BCMOS全差分运算放大器.该运放采用复用型折叠式共源共栅结构、开关电容共模反馈以及增益增强技术,在相同功耗和负载电容条件下,与传统CM0S增益增强型运算放大器相比,具有高单位增益带宽、高摆率及相位裕度改善的特点.在Cadence环境下,基于Jazz 0.35μm BiCMOS标准工艺模型,对电路进行Spectre仿真.在5 V电源电压下,驱动6pF 负载时,获得开环增益为115.3 dB、单位增益带宽为161.7 MHz、开环相位裕度为77.3°、摆率为327.0 V/μm、直流功耗(电流)为1.5 mA.     

面向VR应用的花卉植物物理渲染技术研究与实现

花卉植物高真实感的仿真交互是目前虚拟植物可视化研究的一个重要方向。随着虚拟现实技术的普及,越来越多的应用采用了VR头戴设备的呈现方式。VR系统需要高度真实的沉浸感画面,通用的植物建模和图形引擎渲染功能已不能满足该需求。该文通过分析光照原理并融合基于物理的渲染技术,提出基于双向散射分布函数BSDF的花卉植物高度真实感的物理渲染算法,利用ShaderLab,对几种盆栽花卉植物在光照下进行仿真,并对融合算法做优化处理。针对VR头盔设备HTC Vive的成像效果,对图像进行扭曲变形优化,使画面更符合人眼双目立体视觉成像效果,增强系统沉浸感。最后基于该方法设计并实现了一个头盔式VR花卉植物仿真模拟系统,获得了逼真的场景漫游体验效果。     

Bottom‐Up Preparation of Fully sp2‐Bonded Porous Carbons with High Photoactivities

Porous carbons, possessing exceptional stability, high surface area, and electric conductivity, are broadly used as superior adsorbent, supporter, or electrode material for environmental protection, industrial catalysis, and energy storage and conversion. The construction of such kinds of materials with designable structures and properties will extremely extend their potential applications, but remains a huge synthetic challenge. Herein, a bottom‐up approach is presented to synthesize one type of fully sp² carbon–bonded frameworks by transition metal–catalyzed cross‐coupling of different polyphenylenes with electron‐withdrawing 9,9′‐bifluorenylidene (9,9′‐BF) through its 2,7‐position. The resulting porous polymeric carbons exhibit substantial semiconducting properties, such as strong light‐harvesting capabilities in the visible light region, likely due to their π‐extended backbones with donor–acceptor characters. Their electronic and porous structures can be finely tuned via the polyphenylene spacers. The intriguing properties allow these porous carbons to efficiently catalyze dye degradation under visible light or even natural sunlight with high reusability. Meanwhile, associated with their intrinsic structures, these porous carbons also exhibit highly selective degradation activities toward different dyes. In particular, the photodegradation mechanism involving oxygen and electron is elucidated for the first time for such kinds of materials, related to the presence of specific 9,9′‐BF units in their π‐conjugated skeletons.     

基于有限元的脉冲激光辐照材料温度场研究

在激光超声检测过程中,为了合理加载脉冲激光的能量,以便获得幅值较大的超声波信号,同时避免脉冲激光造成材料的损伤,需要对脉冲激光辐照材料的温升进行数值计算。依据有限元理论,建立脉冲激光辐照材料的有限元模型,结合导热微分方程,将脉冲激光以热流密度的形式加载于材料表面,分析材料表层受激光辐照时的温度场,讨论有限元热分析时网格尺寸的选取对分析结果的影响。给出了材料表层受脉冲激光辐照时温度场的计算方法和网格尺寸的选择依据,并利用温度场的理论解析结果和应力场分析结果分别验证了温度场有限元计算方法的正确性和有效性。     

基于Legendre神经网络的单目视觉相对位姿解算

将BP神经网络、RBF神经网络以及Legendre正交基神经网络应用于单目视觉相对位姿强非线性解算,并且在梯度下降法的基础上推导了Legendre正交基神经网络的最优权值,最后进行了相应的仿真及物理实验.实验结果表明,基于Legendre正交基神经网络的单目视觉相对位姿解算方法不仅精度高、鲁棒性强,而且实时性较好.