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61.
L. Raniero N. Martins P. Canhola S. Zhang S. Pereira I. Ferreira E. Fortunato R. Martins 《Solar Energy Materials & Solar Cells》2005,87(1-4):349
The aim of this work is to present data concerning the optimization of performances of a large area amorphous silicon p–i–n solar cell (30×40 cm2) deposited by plasma enhanced chemical vapour deposition (PECVD) at 27.12 MHz. In this work the solar cell was split into small areas of 0.126 cm2, aiming to study the device performance uniformity, where emphasis was put on the role of the n-layer thickness. The solar cells were studied through the spectral response behaviour in the 400–750 nm range as well as by the behaviour of the AC impedance. Solar cells with fill factor of 0.58, open circuit voltage of 0.83 V, short circuit current density of 17.14 mA/cm2 and an efficiency of 8% were obtained at growth rates higher than 0.3 nm/s. 相似文献
62.
S. Zhang X. Liao L. Raniero E. Fortunato Y. Xu G. Kong H. guas I. Ferreira R. Martins 《Solar Energy Materials & Solar Cells》2006,90(18-19):3001-3008
Diphasic silicon films (nc-Si/a-Si:H) have been prepared by a new regime of plasma enhanced chemical vapour deposition in the region adjacent of phase transition from amorphous to microcrystalline state. Comparing to the conventional amorphous silicon (a-Si:H), the nc-Si/a-Si:H has higher photoconductivity (σph), better stability, and a broader light spectral response range in the longer wavelength range. It can be found from Raman spectra that there is a notable improvement in the medium range order. The blue shift for the stretching mode and red shift for the wagging mode in the IR spectra also show the variation of the microstructure. By using this kind of film as intrinsic layer, a p–i–n junction solar cell was prepared with the initial efficiency of 8.51% and a stabilized efficiency of 8.01% (AM1.5, 100 mw/cm2) at room temperature. 相似文献
63.
何谓永恒城市与火车之间的爱恨情仇/关系源远流长,有过激情四溢的乐章,也有过痛苦折磨的片断,有过甜蜜美好的瞬间,也有公诸于众的背叛。而今,两者之间的关系历经变化,今非昔比。然而在巴伦西亚的杰昆·索罗拉火车站,城市与火车之间的激情烈焰仍在燃烧。新车站在允许高速火车进行停靠的同时,完成了将铁轨迁入地下的工程: 相似文献
64.
Konstantin B. Shumaev Olga V. Kosmachevskaya Elvira I. Nasybullina Enno K. Ruuge Alexey F. Topunov 《International journal of molecular sciences》2023,24(1)
Carbonyl stress occurs when reactive carbonyl compounds (RCC), such as reducing sugars, dicarbonyls etc., accumulate in the organism. The interaction of RCC carbonyl groups with amino groups of molecules is called the Maillard reaction. One of the most active RCCs is α-dicarbonyl methylglyoxal (MG) that modifies biomolecules forming non-enzymatic glycation products. Organic free radicals are formed in the reaction between MG and lysine or Nα-acetyllysine. S-nitrosothiols and nitric oxide (•NO) donor PAPA NONOate increased the yield of organic free radical intermediates, while other •NO-derived metabolites, namely, nitroxyl anion and dinitrosyl iron complexes (DNICs) decreased it. At the late stages of the Maillard reaction, S-nitrosoglutathione (GSNO) also inhibited the formation of glycation end products (AGEs). The formation of a new type of DNICs, bound with Maillard reaction products, was found. The results obtained were used to explain the glycation features of legume hemoglobin—leghemoglobin (Lb), which is a lysine-rich protein. In Lb, lysine residues can form fluorescent cross-linked AGEs, and •NO-derived metabolites slow down their formation. The knowledge of these processes can be used to increase the stability of Lb. It can help in better understanding the impact of stress factors on legume plants and contribute to the production of recombinant Lb for biotechnology. 相似文献
65.
Claudia Mihaela Ninciuleanu Raluca Ianchi Elvira Alexandrescu Ctlin Ionu Mihescu Sabina Burlacu Bogdan Tric Cristina Lavinia Nistor Silviu Preda Cristina Scomoroscenco Ctlina Gîfu Cristian Petcu Mircea Teodorescu 《International journal of molecular sciences》2022,23(18)
The present work aims to show how the main properties of poly(methacrylic acid) (PMAA) hydrogels can be engineered by means of several silicon-based fillers (Laponite XLS/XLG, montmorillonite (Mt), pyrogenic silica (PS)) employed at 10 wt% concentration based on MAA. Various techniques (FT-IR, XRD, TGA, SEM, TEM, DLS, rheological measurements, UV-VIS) were used to comparatively study the effect of these fillers, in correlation with their characteristics, upon the structure and swelling, viscoelastic, and water decontamination properties of (nano)composite hydrogels. The experiments demonstrated that the nanocomposite hydrogel morphology was dictated by the way the filler particles dispersed in water. The equilibrium swelling degree (SDe) depended on both the pH of the environment and the filler nature. At pH 1.2, a slight crosslinking effect of the fillers was evidenced, increasing in the order Mt < Laponite < PS. At pH > pKaMAA (pH 5.4; 7.4; 9.5), the Laponite/Mt-containing hydrogels displayed a higher SDe as compared to the neat one, while at pH 7.4/9.5 the PS-filled hydrogels surprisingly displayed the highest SDe. Rheological measurements on as-prepared hydrogels showed that the filler addition improved the mechanical properties. After equilibrium swelling at pH 5.4, G’ and G” depended on the filler, the Laponite-reinforced hydrogels proving to be the strongest. The (nano)composite hydrogels synthesized displayed filler-dependent absorption properties of two cationic dyes used as model water pollutants, Laponite XLS-reinforced hydrogel demonstrating both the highest absorption rate and absorption capacity. Besides wastewater purification, the (nano)composite hydrogels described here may also find applications in the pharmaceutical field as devices for the controlled release of drugs. 相似文献
66.
Leda Cristina Muzzi Cunha Maria Lúcia Guerra Monteiro Bruno Reis Carneiro da Costa-Lima Juliana Maria Guedes-Oliveira Bruna Leal Rodrigues Alice Raquel Fortunato Jéssica Diogo Baltar Renata Valeriano Tonon Tatiana Koutchma Carlos Adam Conte-Junior 《Journal of Food Processing and Preservation》2021,45(3):e15272
67.
Giuseppe Curr Marco Camalleri Denise Calì Francesca Monforte Fortunato Neri 《Microelectronics Reliability》2007,47(4-5):798
A detailed study of the carrier trapping properties shown by the silicon/oxynitride/oxide gate layers in PowerVDMOS technologies is reported. A quantitative analysis of hole and electron trap densities versus the specific N2O based nitridation process, extracted from Fowler–Nordheim constant current stress kinetics, allows a deep understanding of the role played by those defects in the susceptibility of every nitrided layer. 相似文献
68.
Excess noise measurements have been carried out in nonhydrogenated amorphous silicon material at room temperature. The temperature dependence of the conductivity has shown that, at room temperature, noise measurements deal with transport mechanisms dominated by hopping to nearest neighbors. At lower temperature there is variable range hopping from which the number of states near the Fermi level was determined. The ohmic behavior of structures such as molybdenum-amorphous silicon-molybdenum, and the V2 dependence of the noise spectral density indicate that noise is characteristic for this material. A simple theory of phonon assisted hopping noise is presented. From this the fluctuations. Some preliminary data are shown for hydrogenated amorphous silicon. The noise shows a Lorentzian, indicative of generation-recombination noise. 相似文献
69.
广告是源于生活,又从生活中升华的艺术.中国广告的奇花异葩也只有在中国肥沃的历史文化土壤中才能茁壮成长.在这则美的空调的广告中,聪明又简单的创意,直接而真实的视觉演绎以及亲切又幽默的概念传达,让你看后回味无穷. 相似文献
70.