LTE系统中小区搜索定时同步的FPGA设计

对比于传统DSP串行模式,基于FPGA提出了一种并行高效的小区搜索定时同步设计方案。从空中接口接收数据到FPGA的片内存储模块,采用多路高速乘法器进行序列互相关检测和动态门限配置,实现了数据接收和处理的无缝衔接,大大缩短了主同步信号的检测时间,降低了解码复杂度,并以Virtex-6芯片为硬件平台进行了仿真、综合、板级验证、联机验证等工作。实现结果表明,该设计方案的处理速度和数据精度满足LTE系统测试要求,已应用于终端测试仪表的开发中。     

电网电力系统稳定器的交互影响分析

随着我国大区域电网互联的发展,低频振荡已是影响电力系统稳定的重要因素之一.目前,在发电机励磁系统上安装电力系统稳定器(PSS)仍是抑制低频振荡的一种较为经济和有效的方法.在分析了多机系统中PSS的交互影响并考虑多机系统PSS的相关性的基础上,采用特征值灵敏度分析法确定机电振荡模式,建立了优化模型.由特征值对PSS增益的灵敏度构成目标函数,实现了发电机对各机电模式的有效参与,从而求得系统中各机电模式与主参与机组PSS的对应关系.某省级电网系统的计算和分析,验证了所述方法的可行性.     

“Secondary doping” methods to significantly enhance the conductivity of PEDOT:PSS for its application as transparent electrode of optoelectronic devices

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is the most successful conducting polymer in terms of the practical application. It can be dispersed in water and some polar organic solvents, and high-quality PEDOT:PSS films can be readily prepared through solution processing. In addition, PEDOT:PSS is highly transparent in the visible range and has excellent thermal stability. Nevertheless, PEDOT:PSS has a problem of low conductivity. The as-prepared PEDOT:PSS films from its aqueous solution have a conductivity of lower than 1 S cm⁻¹, which severely impedes the application of PEDOT:PSS in various aspects. It has been discovered that the conductivity of as-prepared PEDOT:PSS from its aqueous solution can be significantly enhanced by adding organic compounds like high-boiling point polar organic solvents, ionic liquids and surfactants or through a post-treatment of PEDOT:PSS films with organic compounds, including high-boiling point polar solvents, salts, zwitterions, cosolvents, organic and inorganic acids. Conductivity of more than 3000 S cm⁻¹ was recently observed on PEDOT:PSS films after treated with sulfuric acid. This conductivity is comparable to that of indium tin oxide (ITO), the conventional transparent electrode material of optoelectronic devices. In addition, PEDOT:PSS has high mechanical flexibility while ITO is a brittle material. Thus, PEDOT:PSS is very promising to be the next-generation transparent electrode material. This article reviews the methods to enhance the conductivity of PEDOT:PSS, the mechanisms for the conductivity enhancements and the application of the highly conductive PEDOT:PSS films in polymer light-emitting diodes and polymer solar cells.     

Electroconductive paper prepared by coating with blends of poly(3,4‐ethylenedioxythiophene)/poly(4‐styrenesulfonate) and organic solvents

Electroconductive papers were produced by coating commercial base papers with blends of poly(3,4‐ethylenedioxythiophene)/poly(4‐styrenesulfonate) (PEDOT:PSS) and organic solvents. The bulk conductivities of the coated papers were measured using a four‐probe technique. One‐sided and two‐sided coating gave comparable conductivity levels. The presence of sorbitol and isopropanol in the PEDOT:PSS blends did not enhance the bulk conductivity of the coated paper, and with increasing concentrations of these solvents, the conductivity decreased due to dilution of the conducting component. Samples coated with PEDOT:PSS blends containing N‐methylpyrrolidone (NMP) or dimethyl sulfoxide (DMSO) exhibited a higher conductivity than those coated with pure PEDOT:PSS because of their plasticizing effect and conformational changes of PEDOT molecules indicated by the red shift and disappearance of the shoulder peak at about 1442 cm^?1 in the Raman spectra of the coated samples. EDS imaging showed that PEDOT:PSS is distributed throughout the thickness direction of the paper. Contact angle measurements were made to monitor the hydrophilicity of the paper surface and total sulfur analysis was used to determine the amount of PEDOT:PSS deposited onto the paper. The tensile strength of all the paper samples increased slightly after treatment. Thus, it is demonstrated that enhanced bulk conductivity in the order of 10^?3 S/cm can be achieved by using organic conductive materials and surface treatment techniques. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

正交试验设计优化藻酸双酯钠磺化物的合成工艺

为了优化藻酸双酯磺化物的合成工艺,按L1645正交表设计考察了影响以酯化物、氯磺酸、吡啶、甲酰胺为原料合成藻酸双酯钠磺化物的投料比(A)、反应时间(B)、吡啶用量(C)、滴加温度(D)4个主要因素,每个因素各取4个水平。结果表明:合成的最优反应条件为A3B3C3D1,此合成工艺硫酸盐合格率可达到95.0%以上。     

基于特征值灵敏度的电力系统稳定器配置及参数整定

提出基于特征值对PSS传递函数的灵敏度以及阻尼比对PSS放大倍数的灵敏度分析方法,分别进行PSS的配置以及放大倍数的整定,并通过四机两区域典型系统验证文中所提方法的有效性.     

广域PSS研发及应用

对基于多信号Prony算法的广域PSS（Power System Stabilization）研发及实现进行阐述,从广域PSS和传统PSS区别、广域PSS原理、实现构架、在线整定方法和RTDS仿真试验效果分析等几个方面对责州电网广域PSS研发及实现进行了详细描述,表明该装置正确性和对低频振动抑制的有效性。     

Electrical characteristics of ink-jet printed, all-polymer electrochemical transistors

We report on the fabrication and characterization of inkjet-printed, all-Organic ElectroChemical Transistors (OECTs) entirely realized by a conducting polymer, namely poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonic acid) (PEDOT:PSS). The transistors utilized saline as the electrolyte and exhibited output characteristics typical for operation in depletion regime. The transfer characteristics could be tuned on the basis of device geometry, with the ratio between the area of the channel and the area of the gate electrode determining the transconductance. This work paves the road for the low-cost, print-on-demand fabrication of circuits for applications in bio-sensors and disposable electronics.     

数字式可控硅励磁调节器与PSS及在百色电站的应用

文章叙述了百色水利枢纽工程电站UNITROL 5000型数字式可控硅励磁调节器系统的主要功能及其电力系统稳定器的功能，并介绍了在百色电站的有关试验及参数设定情况。     

A novel hierarchical Pt- and FTO-free counter electrode for dye-sensitized solar cell

A novel hierarchical Pt- and FTO-free counter electrode (CE) for the dye-sensitized solar cell (DSSC) was prepared by spin coating the mixture of TiO₂ nanoparticles and poly(3,4-ethylenedioxy-thiophene):poly(styrenesulfonate) (PEDOT:PSS) solution onto the glass substrate. Compared with traditional Pt/FTO CE, the cost of the new CE is dramatically reduced by the application of bilayer TiO₂-PEDOT:PSS/PEDOT:PSS film and the glass substrate. The sheet resistance of this composite film is 35 Ω sq⁻¹ and is low enough to be used as an electrode. The surface morphologies of TiO₂-PEDOT:PSS layer and modified PEDOT:PSS layer were characterized by scanning electron microscope, which shows that the former had larger surface areas than the latter. Electrochemical impedance spectra and Tafel polarization curves prove that the catalytic activity of TiO₂-PEDOT:PSS/PEDOT:PSS/glass CE is higher than that of PEDOT:PSS/FTO CE and is similar to Pt/FTO CE''s. This new fabricated device with TiO₂-PEDOT:PSS/PEDOT:PSS/glass CE achieves a high power conversion efficiency (PCE) of 4.67%, reaching 91.39% of DSSC with Pt/FTO CE (5.11%).