有机电致发光材料的研发现状

有机电致发光器件 (OLED)具有驱动电压低、主动发光等优势 ,在平板显示领域具有极大的应用前景而引起了广泛的关注。与此同时有机电致发光材料的研发也取得了很大的进展。本文介绍了近年来有机电致发光材料 (包括小分子发光材料和聚合物发光材料 )的研发状况     

Numerical analysis on determining the physical mechanisms contributing to the abnormal base current in post-burn-in AlGaAs/GaAs HBTs

An abnormal base current behavior with an ideality of about 3 is often observed in the AlGaAs/GaAs HBT after it is subjected to a high temperature/electrical burn-in condition. Using a two-dimensional device simulator, this paper studies and determines the main physical mechanisms contributing to such an abnormality. Data measured from two post-burn-in HBTs are included in support of the finding.     

A novel dual-polarity device with symmetrical/asymmetrical S-type I-V characteristics for ESD protection design

A novel and compact device with adjustable forward and reverse conductions and symmetrical/asymmetrical I-V characteristics for ESD (electrostatic discharge) applications is presented. The device allows for the dual-polarity conduction with the proper selection of blocking junction configurations. This design enables high-level ESD protections for various mixed-signal integrated circuits operating under a wide range of symmetrical and asymmetrical bias conditions.     

A 123-mW W-CDMA uplink baseband receiver IC with beamforming capability

In this paper, architecture and circuit design of a beamforming baseband receiver IC for uplink W-CDMA communication systems is presented. In the proposed receiver, a four-antenna-element beamformer and a four-finger RAKE combiner are adopted to exploit both spatial diversity and path diversity receiving. To minimize the size and power consumption of the receiver, a latch-based 1024-tap complex delay line is custom designed for the matched filter in the channel estimation circuit. The receiver chip was fabricated in a 0.35-/spl mu/m n-well CMOS single-poly quadruple-metal technology. The minimum supply voltage with the chip running at the nominal 15.36-MHz clock rate is measured at 2.15 V. The chip has an area of 6 mm by 6.3 mm and a power consumption of about 123 mW.     

Crystallographic Facetting in Sintered Barium Titanate

A commercial TiO₂-excess BaTiO₃ powder has been sintered and its microstructure analyzed for crystallographic facetting via both scanning and transmission electron microscopy (SEM and TEM). Facetted grain surfaces are developed initially from {111} at a low temperature of 1215°C, which are then altered to {111} and {100} at 1290°C in the presence of a grain-boundary liquid phase. The grain shape is also modified correspondingly from platelike to polygonal. Facetting of the intragranularly located residual pores in BaTiO₃ along the {141} planes further develops on the (quasi-)equilibrium shape after annealing at 1400°C for 100 h from the initially well-characterized {111}, {110}, and {100} in as-sintered samples sintered at the same temperature for 10 h. The Wulff plots derived from the residual pores in as-sintered and annealed samples are constructed for the 〈011〉 zone. Microstructural analysis also suggests that the shape of grains and intragranular residual pores is modified progressively upon annealing. The initial solid–vapor surface energy has become less anisotropic crystallographically. Abnormal grain growth in relation to the surface energy anisotropy is discussed.     

邻甲酚醛环氧树脂研究进展

论述了我国邻甲酚醛环氧树脂的生产、研究与应用状况及发展动向,以及与国外的差 距。介绍了邻甲酚醛环氧树脂的三种合成方法,重点论述了真空负压回流加碱生产工艺的特点。     

Inkjet revolution

The use of inkjet technology for the application of thin-film-transistor liquid-crystal display manufacturing.     

煤电化学气化法制氢的动力学研究

研究了煤电化学气化法由水制氢的反应机理,实验验证了非电化学反应4Fe~(3 ) C 2H_2O→4Fe~(2 ) 4H~ CO_2是存在的。同时,通过实验得到了过程的动力学模型或     

Simulated wave-driven ANN model for typhoon waves

This paper investigates an artificial neural network (ANN) model for typhoon waves used to modify poor calculations of the numerical model in special cases. Two key factors, local winds and simulated waves produced by the numerical model, were used as input parameters of the proposed ANN model. The waves were simulated by the numerical model from a wave action equation indicating the physical processes of energy transfer and wave propagation. Simulated wave input is a very important parameter for the proposed ANN model, allowing for the accurate calculation of water waves in the sea. The applicable Mike21_SW model was chosen to provide an accurate calculation. Through model verification, the proposed ANN model has a particularly accurate calculation at the peak of each typhoon and at its occurrence time. The computed waves of each typhoon were examined to be consistent with the observed waves.