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91.
A semiconducting single-walled carbon nanotubes (s-SWCNTs) interlayer between poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and n-Si was used for high performance organic-Si hybrid photovoltaic (PV) devices. The s-SWCNTs films with different thickness were utilized to investigate the PV effect on PEDOT:PSS/Si device performance. The surface potential of Si substrate with s-SWCNTs was dramatically reduced, which increased the compatibility between Si and PEDOT:PSS. In addition, s-SWCNTs with good semiconducting properties, guaranteed the charge transfer between Si and PEDOT:PSS. Therein, the electrical contact was dramatically improved with addition of s-SWCNTs interlayer, which led to increased fill factor. A power conversion efficiency (PCE) of 12.14% was achieved with an optimized thickness of s-SWCNTs layer. The s-SWCNTs interface layer was fabricated by a simple solution processed method, which was easily coupled with organic-Si solar cells to enhance the PCE. 相似文献
92.
93.
In this paper, we proposed a novel adjustable data hiding method. Our proposed method, which is based on exploiting modification direction (EMD) method, is called the “multi-group exploiting modification direction” method. In the multi-group method, we combine several pixel-groups to embed secret data according to the constructed switch map to simply avoid the conversion redundancy of the EMD method and the spatial redundancy of the section-wise strategy, as well as to efficiently increase the probability of achieving larger embedding capacity. According to the experimental results and mathematical justification, we verified that the multi-group method can achieve higher embedding payload and better visual quality of the image than the EMD method and section-wise strategy for simulated and real secret data. 相似文献
94.
该文提出了现行插头插座国家标准的6项修改建汉措施,每项建议措施均列出了修改原因分析、具体建议措施以及可行性分析,为进一步完善我国插头插座国家标准提供建议和思路。 相似文献
95.
设计精确的定位算法是无线传感器网络(Wireless Sensor Networks,WSNs)的研究热点.针对DV-Hop(Distance Vector-Hop)定位算法中节点间距离估计误差较大导致定位不精确的问题,提出了一种具有连续跳数值的三维DV-Hop改进算法.探究了邻居节点间的距离与相应节点位置和通信半径构成的相交球体体积之间的关系,提出了连续跳数值的定义,并通过参数修正给出了其计算方法.通过仿真实验探究了网络环境对参数的影响并确定了参数的取值,使用连续跳数值代替DV-Hop算法中的跳数来降低节点间距离估计误差.仿真实验表明,该算法在不增加算法复杂度以及额外硬件的情况下有效地降低了定位误差. 相似文献
96.
In this paper, a bilayer hole extraction layer (HEL) with solution-processed molybdenum trioxide (MoO3) and two-dimensional (2D) material of antimonene was developed to achieve high performance nonfullerene organic solar cells (NF–OSCs). The application of antimonene facilitates effective charge extraction and lowered recombination loss, achieving improved photovoltaic performance. By inserting the antimonene layer, power conversion efficiency (PCE) of devices with MoO3 HEL was increased from 8.92% to 11.30% in OSCs with non-fullerene systems of PBDB-T-2F:IT-4F, which was even much higher than that of the devices with PEDOT:PSS HEL (10.59%). Results make it clear that the solution-processed bilayer MoO3/antimonene HEL shows great potential for application in high performance PEDOT:PSS-free NF–OSCs. 相似文献
97.
针对固体推进剂在改进铝粉燃烧性能方面的迫切需要,以铝粉为基材,FeF_3作为添加剂,采用高能球磨法制备Al-FeF_3复合燃料。通过研究粉末配比、球磨参数等对铝基复合燃料组织、结构以及热性能等的影响,优化制备工艺,获得平均粒径为微米级的铝基复合燃料。热重-差示扫描量热联用技术(TG-DSC)表明,Al-FeF_3复合燃料在氧化过程中,可以实现较低温度下(600~1400℃)的快速氧化。端燃75发动机试车表明,使用Al-FeF_3复合燃料全部取代普通球形铝粉后发动机壳体内部无较大铝粉熔融残渣,残渣率从6.151%下降到4.215%。结果表明,Al-FeF_3复合燃料有助于解决Al粉在推进剂中不完全燃烧的问题,在降低燃烧残渣率,减少发动机两相流损失方面有着潜在应用价值。 相似文献
98.
Xizu Wang Jian Wei Ho Qingyi Yang Hoi Lam Tam Gui Xin Li Kok Wai Cheah Furong Zhu 《Organic Electronics》2011,12(11):1943-1947
In this work, Ag nanoparticles were modified by an ultra-thin plasma-polymerized fluorocarbon film (CFX) to form a composite CFX-modified Ag nanoparticles/indium tin oxide (ITO) anode for application in organic photovoltaic (OPV) devices. A CFX-modified Ag nanoparticles/ITO anode exhibited a superior surface work function of 5.4 eV suited for application in OPV devices. The performance of zinc phthalocyanine:fullerene-based OPV devices showed a significant improvement when the structural identical cells are made with the CFX-modified Ag nanoparticles/ITO. This work yielded a promising power conversion efficiency of 3.5 ± 0.1%, notably higher than that with a bare ITO anode (2.7 ± 0.1%). 相似文献
99.
100.