Estimating thermal stress in BIPV modules

The thermal stress on building‐integrated photovoltaic modules (BIPV) in Espoo, Finland, was studied with field‐testing of amorphous silicon modules. Based on these results, the thermal stress at two other European locations (Paris and Lisbon) was estimated. The estimation procedure entailed thermal modelling of heat transfer in the façade with meteorological data as input. The results indicate that the thermal stress on BIPV modules in Lisbon is, in this case, approximately 50% higher that in Espoo and between 80 and 200% higher than in Paris, depending on the activation energy of the degradation process. The difference in stress between a BIPV module and a free‐standing module in Espoo was 50–200%. Copyright © 2006 John Wiley & Sons, Ltd.     

Chemical vapor deposition of aluminum for ulsi applications

Aluminum has been used widely as a conducting material in the fabrication of integrated circuits, and chemical vapor deposition process for Al has been actively investigated for the application in ultra large scale integration. In this review, various precursors, mainly alkyl aluminum and alane compounds, and reaction mechanisms of these precursors in Al CVI) are described. Epitaxial growth and selectivity of the deposition are also discussed. In addition to thermal reactions, plasma and photochemical reactions are also briefly described.     

Electroluminescence from phenylenevinylene-based polymer blends

The electroluminescent behaviour of films of poly(phenylphenylenevinylene) (PPPV), of PPPV blended with polystyrene (PS) and of PS doped with oligo(phenylenevinylene) sandwiched between indium–tin oxide (ITO) and Al contacts has been investigated. Polymer blending increases the relative quantum efficiency by up to two orders of magnitude. Studying the cell performance under application of rectangular voltage pulses as a function of temperature indicates that (i) hole injection at the ITO contact occurs by tunnelling, (ii) tunnel injection of electrons at the cathode is promoted by a space charge field across an interfacial Al₂O₃ layers and (iii) leakage of holes through the cathodic barrier is the main loss mechanism for holes.     

Electrochemical properties of ultra-long,aligned, carbon nanotube array electrode in organic electrolyte

The electrochemical properties of an electrochemical double-layer capacitor electrode based on an ultra-long (500 μm), aligned, carbon nanotube array (ACNTA) in Et₄NPF₆/propylene carbonate electrolyte are examined. The specific capacitance of the ACNTA electrode in an organic electrolyte is 24.5 F g⁻¹, which is larger than that obtained in an aqueous electrolyte. The results of ac impedance measurements show that the ACNTA electrode gives a high power density and an excellent rate capability in an organic electrolyte. It is shown that the ACNTA electrode has a lower equivalent series resistance and a better rate capability than activated carbon electrode. This is due to the fact that ACNTA possesses a larger pore size and a more a regular pore structure. Both these features are conformed by scanning electron microscopic and nitrogen gas adsorption studies.     

有机薄膜电致发光器件的结构

有机薄膜电致发光现象及其广阔的应用前景，激发了人们的研究兴趣。本文介绍了器件结构的研究现状。     

Evaluation of different coating systems by electrochemical methods

Corrosion protection of organic coated steel is determined by free corrosion potential measurements and impedance spectroscopy. The results are classified by means of very basic considerations and evaluation figures are developed. These electrochemical data are correlated with the extent of the corrosion for each coating system. The evaluation figures are used for ranking coating systems and this ranking is correlated with the ranking with reference to the results of standardized and exposure tests.     

两种具有电双稳态的全有机络合物

首次发现两种在室温下即具有电双稳态的全有机（有机-有机）络合物，分别称为MCA＋TCNQ和BBDN＋TCNQ。它们可在真空中制备成薄膜，在数伏电压的作用下，从高电阻至低电阻的跃迁时间小于100ns，因此可作为一次写入的存储器材料。根据我国目前最小刻线宽度的水平，可望在1．6cm2的SiO2平面上做出64Mb的存储器。     

Photovoltaic effect and carrier transport mechanisms in Hg1-Mnxtdiodes

Hg_1-xMn_xTe semiconducting semimagnetic alloy has been examined in the context of its possible applications in infrared detectors. For analysis of detector properties the intrinsic carrier concentration has been calculated as a function of temperature and crystal composition. The starting material was In-doped Hg_1-xMn_xTe grown by the modified Bridgman method. The as-grown crystals with manganese content of 12-19% were p-type with carrier concentration and mobility of 100 cm²/ Vs at 77 K. An-type layer was formed on the surface by the annealing process in saturated Hg-vapour at 270-320° for 2 hrs. Capacitance-voltage curves have C^-3 dependence on applied voltage indicating that the junction is linearly graded. From standard electrical measurements and spectral characteristics the main detector parameters were determined and compared to those of Hg_1-xCd_xTe devices. The influence of material properties on detector parameters was analyzed. In order to estimate the carrier transport mechanisms, differential resistivities and current-voltage curves were measured over a wide range of temperaturesi.e. 25 to 300 K. From the temperature dependence of the R₀A product, it was established that at high temperatures (150-300 K) the carrier transport is dominated by a recombination-generation mechanism. In low temperature region the excess current at forward bias is probably attributed to carrier tunneling via energy states distributed randomly within the forbidden gap. At reverse bias the leakage surface or volume currents dominate in the carrier transport.     

光伏发电接入对配电网低压台区线损的影响

随着可再生能源的不断开发,越来越多的光伏发电接入配电网,而光伏发电的不稳定性会对配电网的稳定造成影响。为此,针对光伏发电对配电网低压台区线损的影响,建立了电源接入模型并进行了仿真计算。     

Modified g-C3N4 derived from ionic liquid and urea for promoting visible-light photodegradation of organic pollutants

In this work, modified g-C₃N₄ was fabricated successfully by calcination of ionic liquid (IL) and urea. The addition of IL changed the polymerization mode of urea, induced the self-assembly of urea molecules, modified the morphological structure of the tightly packed g-C₃N₄, and extended the electron conjugation system. When using 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) as a modifier, the heteroatom Cl could be inserted into the g-C₃N₄ to optimize the electronic structure. The results of characterizations indicate that the unique structure of modified g-C₃N₄ has an expanded electron delocalization range, introduces an interlayer charge transmission channel, promotes the charge transmission, reduces the band gap, enhances the absorption of visible light, and inhibits electron-hole recombination. Modified g-C₃N₄ showed excellent photocatalytic performance for the degradation of rhodamine B and tetracycline. Furthermore, the effect of different anions in 1-butyl-3-methylimidazolium salts ([Bmim]Cl, [Bmim]Br, [Bmim][BF₄], and [Bmim][PF₆]) on the structure and function of g-C₃N₄ are discussed.