Recent advances of dithienobenzodithiophene-based organic semiconductors for organic electronics

In recent years, fused aromatic dithienobenzodithiophene(DTBDT)-based functional semiconductors have been potential candidates for organic electronics. Due to the favorable features of excellent planarity, strong crystallinity, high mobility, and so on, DTBDT-based semiconductors have demonstrated remarkable performance in organic electronic devices, such as organic feld-effect transistor(OFET), organic photovoltaic(OPV), organic photodetectors(OPDs). Driven by this success, recent developments in the area of DTBDT-based semiconductors for applications in electronic devices are reviewed, focusing on OFET, OPV, perovskite solar cells(PSCs), and other organic electronic devices with a discussion of the relationship between molecular structure and device performance. Finally, the remaining challenges, and the key research direction in the near future are proposed, which provide a useful guidance for the design of DTBDT-based materials.     

四极子微腔的光场分布

应用电磁场理论和介质中的麦克斯韦方程组,推导了任意截面微腔的TM模光场分布。并以四极子状微腔截面为例,推导了含有传播常数的本征方程。用Mathematica软件模拟出具有不同变形因子的基模(m=1)和高阶模的光场分布图,得出基模在=45°,135°,225°,315°四个方向光辐射最强,具有“蝴蝶结模式”特征,并且当变形因子值取ε′为0.1~0.15时,该效应表现得更明显;而高阶模(m≥2)时微腔中没有这种光的定向输出现象,在任何变形因子情况下也不能形成稳定的“蝴蝶结模式”,为四极子微腔激光器的设计和制作提供了一定的理论依据。     

GaAs FET功率放大器温度补偿的设计

介绍了GaAs FET功率放大器温度补偿的基本原理,分析了GaAs FET功率放大器的增益随温度变化的原因,并给出了解决方法。此方法还可移植到其他类似需要温度补偿的放大器中。     

用MATLAB回归非线性模型参数

非线性模型参数回归难度大,需要一定的数学基础,用MATLAB回归分析工具箱可直接进行非线性回归,计算简单准确,并能给出直观的拟合曲线图。     

卷入Hohlov 算子的双单值函数某些子类的Fekete-Szeg\"o泛函问题

In the paper the new subclasses■and■of the function class∑of bi-univalent functions involving the Hohlov operator are introduced and investigated.Then,the corresponding Fekete-Szeg functional inequalities as well as the bound estimates of the coefficients a2 and a3 are obtained.Furthermore,several consequences and connections to some of the earlier known results also are given.     

Measurements of neutron energy spectra of 9Be(d,n)10B reaction with a thick beryllium target

Novel measurements of the neutron energy spectra of the 9Be(d,n)10B reaction with a thick beryllium target are performed using a fast neutron time-of-flight(TOF)spectrometer for the neutron emission angles θ=0°and 45°,and the incident deuteron energies are 250 and 300 keV,respectively.The neutron contributions from the 9Be(d,n)10B reaction are distributed relatively independently for the ground state and the first,second,and third excited states of 10B.The branching ratios of the 9Be(d,n)10B reaction for the different excited states of 10B are obtained for the neutron emission angles θ=0°and 45°,and the incident deuteron energies are 250 and 300 keV,respectively.The branching ratio of the 9Be(d,n)10B reaction for the third excited state decreases with increase in the incident deuteron energy,and the branching ratios for the ground state and the second excited state increase with increase in the neutron emission angle.     

超声无铆静力学性能强化试验与机制研究*

无铆连接是一种薄板材料连接新技术,可在无需预成孔和表面预处理情况下,实现同种、异种、多层薄板材料高效连接,但由于无铆接头静力学性能较低,极大地限制了该连接技术的推广与发展。为解决这一难题,本文选用5A06铝合金与TA1钛合金进行同种金属无铆铆接,并在此基础上进行了超声金属焊接复合实验,基于静拉伸测试和扫描电镜分析,探究超声焊对无铆接头力学性能的强化机制。试验结果表明：超声焊可有效提升无铆接头力学性能,特别是对于铝合金无铆接头;超声焊使得铝合金板塑性提高,钛合金板则得到硬化;超声焊后无铆接头的受力形式发生改变,从颈部受力变为先焊合区受力再颈部受力,这是超声焊复合强化的根本原因;超声焊可使铝合金无铆接头内部形成一定深度的固相焊,使铝合金接头力学性能得到大幅提升;TA1钛合金无铆接头内部固相焊较浅,力学性能提升相对较低。     

Electroplating Cobalt Films on Silicon Nanostructures for Sensing Molecules

In this study, we electroplated Co and Cu on nano-spiked silicon substrates that were treated with femtosecond laser irradiations. With energy-dispersive X-ray (EDX) analysis by a scanning electron microscope (SEM), it was found that both Co and Cu are primarily coated on the spike surfaces without changing the morphology of the nanospikes. We also found that nanoscale bridges were formed, connecting the Co-coated silicon spikes. The formation of these bridges was studied and optimized through a series of time-controlled electroplating and oxidizing processes. The bridges are related to the oxidation of Co in the air. When it is irradiated with visible light, this special structure has shown a capability of interactions with carbon monoxide and carbon dioxide molecules. The electroplated cobalt may be used for gas sensors.