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71.
Light‐induced degradation (LID) has been identified to be a critical issue for solar cells processed on boron‐doped silicon substrates. Typically, Czochralski‐grown silicon (Cz‐Si) has been reported to suffer from stronger LID than block‐cast multicrystalline silicon (mc‐Si) due to higher oxygen concentrations. This work investigates LID under conditions practically relevant under module operation on different cell types. It is shown that aluminium oxide (AlOx) passivated mc‐Si solar cells degrade more than a reference aluminium back surface field mc‐Si cell and, remarkably, an AlOx passivated Cz‐Si solar cell. The defect which is activated by illumination is shown to be doubtful a sole bulk effect while the AlOx passivation might play a certain role. This work may contribute to a re‐evaluation of the suitability of boron‐doped Cz‐ and mc‐Si for solar cells with very high efficiencies. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
72.
Eduard Hryha Henrik Borgström Karin Sterky Lars Nyborg 《Journal of Thermal Analysis and Calorimetry》2014,118(2):695-704
Binders present an important part of the powder metallurgy technology as they are vital to provide efficient powder agglomeration and/or lubrication during shaping. At the same time, they have to be easily removed from the compacts during initial stages of sintering without any harmful effect for the base material, as well as for the environment. Therefore, behavior of gelatin as a binder for stainless- and tool-steel gas-atomised powder compacts was studied by thermal analysis and electron microscopy. Thermal analysis showed that peak mass-loss occurred in the range between 340 and 370 °C, depending on the base powder and heating rate. Risk for base powder oxidation at temperatures below 425 °C was detected. Based on the obtained results, it is recommended to perform debinding at ~425 °C after applying a heating rate of around 7.5 °C min?1. Only in this way efficient enough binder removal can be obtained concurrently to avoiding base powder oxidation. 相似文献
73.
Marcos V. Foguel Angelica M. Balcarcel Mark A. Reed Percy Calvo‐Marzal Yulia V. Gerasimova Dmitry M. Kolpashchikov Karin Y. Chumbimuni‐Torres 《Electroanalysis》2020,32(4):835-841
One major challenge in nucleic acids analysis by hybridization probes is a compromise between the probe's tight binding and sequence‐selective recognition of nucleic acid targets folded into stable secondary structures. We have been developing a four‐way junction (4WJ)‐based sensor that consists of a universal stem‐loop (USL) probe immobilized on an electrode surface and two adaptor strands (M and F). The sensor was shown to be highly selective towards single base mismatches at room temperature, able to detect multiple targets using the same USL probe, and have improved ability to detect folded nucleic acids. However, some nucleic acid targets, including natural RNA, are folded into very stable secondary and tertiary structures, which may represent a challenge even for the 4WJ sensors. This work describes a new sensor, named MVF since it uses three probe stands M, V and F, which further improves the performance of 4WJ sensors with folded targets. The MVF sensor interrogating a 16S rRNA NASBA amplicon with calculated folding energy of ?32.82 kcal/mol has demonstrated 2.5‐fold improvement in a signal‐to‐background ratio in comparison with a 4WJ sensor lacking strand V. The proposed design can be used as a general strategy in the analysis of folded nucleic acids including natural RNA. 相似文献
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77.
Karin Erdmann Daniel K. Nakano 《Transactions of the American Mathematical Society》2002,354(1):275-285
In this paper we provide a complete classification of the representation type for the blocks for the Hecke algebra of type , stated in terms of combinatorical data. The computation of the complexity of Young modules is a key component in the proof of this classification result. 相似文献
78.
Simal F Delfosse S Demonceau A Noels AF Denk K Kohl FJ Weskamp T Herrmann WA 《Chemistry (Weinheim an der Bergstrasse, Germany)》2002,8(13):3047-3052
Air-stable and readily available ruthenium benzylidene complexes of the general type [RuCl2(=CHPh)(L)(L')] (L, L' = PCy3 and/or N-heterocyclic carbene) constitute a new class of catalyst precursors for atom-transfer radical polymerization (ATRP) of methyl methacrylate and styrene, and provide an unprecedented example for the involvement of ruthenium alkylidenes in radical reactions. They promote the polymerization of various monomers with good to excellent yields, and in a controlled way with methyl methacrylate and styrene. Variations of their basic structural motif provide insights into the essential parameters responsible for catalytic activity. The ligands L (PCy3 and/or N-heterocyclic carbene) turned out to play a particularly important role in determining the rate of the polymerizations. A similarly pronounced influence is exerted by the substituents on the N-heterocyclic carbene. Our results indicate that the catalysts decompose quickly under ATRP conditions, and polymerizations are mediated by both [RuCl2(=CHPh)(L)(L')] complexes and ruthenium species bereft of the benzylidene moiety, through a pathway in which both tricyclohexylphosphane and/or N-heterocyclic carbene ligands remain bound to the metal center. Polymerization of n-butyl acrylate and vinyl acetate is not controlled and most probably takes place through a redox-initiated free-radical process. 相似文献
79.
We determined the feasibility of using capillary electrophoresis with postcolumn laser-induced fluorescence (CE-LIF) detection to characterize electrophoretic properties of isolated cell nuclei and impurities present in nuclear fractions. These fractions were isolated from NS-1 mouse hybridoma cells, stained with hexidium iodide, a DNA intercalating dye, and analyzed by CE-LIF detection. The corresponding electropherograms display two features: (i) broad peaks (6-90 s wide) caused by the cell culturing media and by free-DNA intercalated with hexidium iodide, and (ii) a large number of narrow peaks (180 ms wide), resulting from DNA associated with individual intact or disrupted nuclei. We confirmed that the narrow peaks were not caused by contaminating mitochondria. The overall electrophoretic mobility range of disrupted nuclei is 0 to -5 x 10(-4)cm(2)/Vs, while intact nuclei seem to have mobilities in the -1.5 to -3.5 x 10(-4)cm(2)/Vs range. Furthermore, the highly sensitive CE-LIF method reveals a high abundance of disrupted nuclei that cannot be directly observed by confocal microscopy. 相似文献
80.
Venkatraman S Anand VG PrabhuRaja V Rath H Sankar J Chandrashekar TK Teng W Senge KR 《Chemical communications (Cambridge, England)》2002,(16):1660-1661
First successful syntheses and structural characterization of new core modified meso aryl azuliporphyrins by a simple [3 + 1] methodology are reported. 相似文献