A screen-printed interdigitated back contact cell using a boron-source diffusion barrier

A low-cost approach to fabricating interdigitated back contact cells is carried out on the principle of screen-printing a material that serves both to dope the rear surface and as a diffusion barrier to the dopant species of the opposite polarity. With this technique, an interdigitated pattern of n⁺ and p⁺ regions is formed on the cell back. Shunt-free rear interdigitated junctions are achieved. This work produced a cell with confirmed conversion efficiency of 10.5%. Areas for further efficiency gains are discussed.     

客车发动机在中国的现状和发展趋势

结合我国现有国情,论述客车用发动机:燃油车、混合动力车、电动车、燃料电池和氢燃料车的现状和发展趋势,着重探讨了CNG/LNG车在我国的现状和发展趋势,并对各项动力进行综合比较分析。     

酞菁铜衍生物LB膜／N－Si光伏电池的反常二极管整流效应

从表面态和材料电阻率的角度分析了酞菁铜衍生物ＬＢ膜光伏电池的反常整流效应，讨论了该效应与光生电流的关系，并介绍了消除反常现象提高光生电流的实验方法。     

TDB－100硅太阳电池仿真及P－V特性研究

采用多项式数学模型对ＴＤＢ－１００硅太阳电池实测Ｉ－Ｖ数据进行拟合，可得到电池的实验模型，该模类具有很高的精度。运用这个模型对Ｐ－Ｖ特性进行分析，并根据电池的光照及温度特性，将该模型进行扩展，得到了电池的预计模型。     

14C labelling of lignins of normal and bm3 maizes for fermentation studies

[U-¹⁴C] phenylalanine (phe*) and [O¹⁴CH₃] sinapic acid (sin*) were infused into the cut ends of normal and bm3 maizes (anthesis stage) under or above the last node or at mid-internode, with or without the leaf, in light or in darkness. Radioactivity was measured in the organs, and in phenolic constituents of the cell wall and saponified residues of the bases and tops of the apical inter-node. In both maize genotype labelled under the node the radioactivity was distributed more evenly in the organs with sin* than with phe*. Infusion above the node and at mid-internode greatly increased radioactivity in the bases and tops, respectively. Removal of the leaf only slightly increased the radioactivity, mainly in the bases, and no clear-cut effect of darkness was observed. Phe* labelled the phenolic acids and the three lignin units, but the syringyl units of bm3 maize were only slightly labelled. Sin* specifically labelled the syringyl units, which represented the least condensed fraction of lignins. Both the native and labelled lignins were highly alkali soluble. There were differences in lignin biogenesis between the bases and tops, and between normal and bm3 maizes. The newly formed lignins were slightly different from the native lignins but had similar types of heterogeneity, with variations in the internode and between genotypes similar to those in native lignins. Provided due allowance is made for the distinguishing characteristics of newly formed lignins, the [¹⁴C-lignin] cell walls, which are strongly labelled on complementary structures, seem suitable model substrates for fermentation studies.     

GSM与WCDMA互操作策略及应用分析

GSM与WCDMA网络之间的互操作是3G网络基于2G网络渐进发展的主要特征之一,是运营商投资效益最大化的必要保证,积极开展双网互操作策略研究及应用实践成为现阶段中国联通网络优化的重点所在,文章结合现网实际应用情况对互操作策略进行了探讨。     

基于虚拟气体传感器阵列的肺癌检测电子鼻

提出了一种无创电子鼻诊断肺癌的新方法。该方法结合虚拟声表面波（SAW）传感器阵列的概念和图像识别方法，对肺癌病人、正常人和老慢支病人的呼出气体进行了检测，确定11种挥发性有机成分（VOCs）为肺癌特征气体。此外，在细胞水平上进行研究，证明了肺癌细胞培养液中存在的特征性VOCs是肺癌细胞新陈代谢的产物，可以作为判定特定肺癌细胞的依据，为确定肺癌病人呼吸中的特征性气体提供病理根据。     

Structural,optical and electrical properties of Cu2FeSnSe4 and Cu(In,Al)Se2 thin films

Cu-based semiconductors Cu₂FeSnSe₄ (CFTSe) and Cu(In, Al)Se₂ (CIAS) have been fabricated using radio-frequency magnetron sputtering combined with rapid thermal selenization processing. For CFTSe, the heating rate ranging from 60 to 150 °C/min results in a difference in structure, morphology and optical properties. Thin film exhibits a pure phase structure, smooth surface and a band gap of 1.19 eV as the heating rate elevated to 90 °C/min. Furthermore, the CFTSe thin film selenized at 90 °C/min own the smallest value of cell volume compared with the others samples, which represents a more stable structure. In terms of the other Cu-based material CIAS, three different selenization pressures, i.e., 1, 5 and 10 Torr, have been employed for CIAS preparation. Thin film transforms into single phase with dense morphology along with the pressure of 1 Torr. The diverse band gap of CIAS thin films from 1.34 to 2.18 eV attribute to two reasons: (i) the various Al content will affect the hybridization degree of Al–Se, and finally tunes the band structure, (ii) amounts of CuSe has a certain degree of effect on the band gap of the CIAS. In addition, the electrical properties of CFTSe and CIAS are also researched with the open circuit voltage (V_oc) of 94 and 365 mV, respectively, signifying potential applications of CFTSe and CIAS for the thin film solar cells.     

CuAlO2 powder dispersed in composite gel electrolyte for application in quasi-solid state dye-sensitized solar cells

The use of delafossite CuAlO₂ (CAO) powder as an additive in composite gel electrolyte (CGE) of the quasi-solid state dye-sensitized solar cell (DSSC) is first reported. In order to achieve an improvement of power conversion and long-term performance of the quasi-solid state DSSC, different contents of CAO powder containing in CGE, a mixture of polyethylene glycol (PEG), iodide/tri-iodide (I⁻/I₃⁻) liquid electrolyte (LE) and 4-tertbutylpyridine (4-tBP), were used in the present study. The photocurrent density–voltage characteristic (J–V curve) and photovoltaic performance parameters of the cells, such as the short-circuit current density (J_sc), open-circuit voltage (V_oc), power conversion efficiency (η) and fill factor (FF) were investigated. The CGE containing the dispersed CAO powder exhibited high ionic conductivity due to the charge diffusion through free channels. The power conversion efficiency of the quasi-solid state DSSC was significantly improved by adding CAO powder to the CGE. The optimum CAO powder content in the CGE was 0.05 wt%. In this research, the power conversion efficiency was 1.71 times of the LE and 2.85 times of the CGE with no CAO powder adding. The quasi-solid state DSSC based on the addition of CAO powder to CGE had long-term stability better than the normal DSSC based on the LE.