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71.
H.-J. Muffler M. Br I. Lauermann K. Rahne M. Schrder M.C. Lux-Steiner C.-H. Fischer T.P. Niesen F. Karg 《Solar Energy Materials & Solar Cells》2006,90(18-19):3143-3150
A method for the fixation of colloids by an ion-layer-gas-reaction-“ILGAR”-oxide layer is presented. The embedding of CdS nano-particles in an ILGAR-ZnO/Zn(OH)2-matrix is confirmed by transmission electron micrographs (TEM); the composition of the layer surface is analyzed by X-ray photoelectron microscopy (XPS). When these particles are fixed by an ILGAR-oxide layer on top of a solar cell the observed absorption and fluorescing properties of CdS nano-particles offer the possibility to reduce the absorption loss in the window layer. This is shown for a Cu(In,Ga)(S,Se)2-“CIGSSe”-based solar cell with an additional top CdSparticle/ILGAR-ZrO2-layer as a first example. The improvement of the device performance is proven by J(V)-characteristics and the external quantum efficiency. 相似文献
72.
V. Probst J. Palm S. Visbeck T. Niesen R. Tlle A. Lerchenberger M. Wendl H. Vogt H. Calwer W. Stetter F. Karg 《Solar Energy Materials & Solar Cells》2006,90(18-19):3115-3123
A second-generation process for high-efficiency large-area Cu(In,Ga)(Se,S)2 thin film (CIGSSe) solar modules has been developed applying controlled sodium doping and rapid thermal processing for absorber formation. The pilot line delivers aperture area efficiencies of 12.2%±0.5% (average) for 30×30 cm2 modules and a certified champion efficiency of 13.1% for an unencapsulated 60×90 cm2 demonstrator module. The stability of the frameless pilot line modules with a low-cost package against humidity is confirmed externally by passing the damp heat test sequence according to IEC 61646. Substitution of CBD-CdS by CBD-Zn(S, OH) buffer layers yields efficiencies up to 12% on 30×30 cm2 circuits. First CIGSSe-cells on flexible substrates were also developed applying 30 μm thin titanium foils, 8×8 cm2 in size. Average cell efficiencies on a substrate up to 12.4% were achieved. 相似文献
73.
Matthias Heymann 《NTM》2009,17(2):171-197
Constructing Climate. From Classical Climatology to Modern Climate Research
Both climate researchers and historians of climate science have conceived climate as a stable and well defined category. This
article argues that such a conception is flawed. In the course of the 19th and 20th century the very concept of climate changed
considerably. Scientists came up with different definitions and concepts of climate, which implied different understandings,
interests, and research approaches. Understanding climate shifted from a timeless, spatial concept at the end of the 19th
century to a spaceless, temporal concept at the end of the 20th. Climatologists in the 19th and early 20th centuries considered
climate as a set of atmospheric characteristics associated with specific places or regions. In this context, while the weather
was subject to change, climate remained largely stable. Of particular interest was the impact of climate on human beings and
the environment. In modern climate research at the close of the 20th century, the concept of climate lost its temporal stability.
Instead, climate change has become a core feature of the understanding of climate and a focus of research interests. Climate
has also lost its immediate association with specific geographical places and become global. The interest is now focused on
the impact of human beings on climate. The paper attempts to investigate these conceptual shifts and their origins and impacts
in order to provide a more comprehensive perspective on the history of climate research. 相似文献
74.
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76.
Matthias F. Groh Alexander Wolff Matthias A. Grasser Michael Ruck 《International journal of molecular sciences》2016,17(9)
Ionic liquids (ILs) have been proven to be valuable reaction media for the synthesis of inorganic materials among an abundance of other applications in different fields of chemistry. Up to now, the syntheses have remained mostly “black boxes”; and researchers have to resort to trial-and-error in order to establish a new synthetic route to a specific compound. This review comprises decisive reaction parameters and techniques for the directed synthesis of polyions of heavy main-group elements (fourth period and beyond) in ILs. Several families of compounds are presented ranging from polyhalides over carbonyl complexes and selenidostannates to homo and heteropolycations. 相似文献
77.
本文采用大涡模拟(LES)的方法研究了在基于外壳直径的雷诺数为9.36×105条件下5叶片的轴流式风扇的流动特性,并且着重分析了叶尖泄漏的流动现象。本文使用了基于有限体积法和分层笛卡尔网格的可压流求解器进行数值计算,并应用了体积守恒的切割网格方法处理风扇几何结构的浸入式边界。同时开发了用于笛卡尔网格的旋转周期性边界条件,这样只需分析由2.5亿网格构造的包含一片叶片的72°区域。该研究首先对网格质量进行了分析,之后讨论了瞬态和时均流场的特性,并与使用RANS的5叶片模拟结果进行了对比。RANS和LES模拟结果的主要不同之处体现在叶尖泄漏涡尾流中的湍流动能。本文进而研究了叶尖间隙对叶尖泄漏涡的影响。研究表明,间隙的大小会影响叶尖泄漏涡的大小形状。此外,间隙中更多的分离现象和反向旋转涡会导致较低的湍流动能。 相似文献
78.
Jürgen Allwohn Martin Brumm Gernot Frenking Matthias Hornivius Werner Massa Friedrich W. Steubert Sigrid Wocadlo 《Advanced Synthesis \u0026amp; Catalysis》1993,335(6):503-514
Synthesis and Conformational Analysis of Pyranophanones and Pyrylophanium Compounds with Intraannular Substituents The synthesis of [3.3]dithiapyranophanone 6 and 11 is accomplished by use of the two-components-dilution-principle. Pyrolysis of their bis(sulfones) 7 and 12 gives the [2.2]pyranophanones 8 , 9 and 13 . Under preservation of conformation the intraannular carbonyl-function is used for the synthesis of methylpyranophanoles 14 , 16 and 17 . The synthesis of pyrylophanium compounds 15 and 18 is possible by elimination in trifluoroacetic acid. 6 exhibits anti-conformation within its crystal-structure and like 7 reveals temperature-dependent behavior in solution. Using 6 as an example, a combination of 13C-NMR-spectroscopy, forcefield-calculation and computer-simulation is applied for the first time to give evidence for molecular-dynamic processes of cyclophanes. 8 and 9 are the syn- and anti-conformers of the desired product, as shown by X-ray structural analysis. 13 reveals anti-conformation within its crystal structure as well as in solution. The conformational analysis of other new phanes described here is based on the 1H-NMR-spectra of these pyrolysis products. As expected the intraannular substituents of Pyrylophanium-lons 15 and 18 show the characteristic upfield-shift within their 1H-NMR-spectra. 相似文献
79.