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101.
Andreas Vetter Finn S. Babbe Bernhard Hofbeck Peter Kubis Michael Richter Stephan J. Heise Jrg Ohland Ingo Riedel Christoph J. Brabec 《Progress in Photovoltaics: Research and Applications》2016,24(7):1001-1008
Local electric defects may result in considerable performance losses in solar cells. Infrared (IR) thermography is one important tool to detect these defects on photovoltaic modules. Qualitative interpretation of IR images has been carried out successfully, but quantitative interpretation has been hampered by the lack of “calibration” defects. The aims of this study are to (i) establish methods to induce well‐defined electric defects in thin‐film solar cells serving as “calibration” defects and to (ii) assess the accuracy of IR imaging methods by using these artificially induced defects. This approach paves the way for improving quality control methods based on imaging in photovoltaic. We created ohmic defects (“shunts”) by using a focused ion beam and weak diodes (“interface shunts”) by applying a femto‐second laser at rather low power on copper indium gallium selenide cells. The defects can be induced precisely and reproducibly, and the severity of the defects on the electrical performance can be well adjusted by focused ion beam/laser parameters. The successive assessment of the IR measurement (ILIT‐Voc) revealed that this method can predict the losses in Pmpp (maximal power extractable) with a mean error of below 10%. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
102.
Char particles from pyrolyzed biomass vary in particle size and shape. On average, the particles are more elongated the larger their size. The average size‐specific elongation is almost alike for all investigated samples, i.e. independent from their source material and process. The particle collectives cannot be characterized accurately with classical particle size distributions, which assume spherical particle shape. Accounting for their shape, they can be described more accurately with particle size distributions that are based on an ellipsoid model. The high bulk porosity is mainly attributed to the spaces between particles. 相似文献
103.
Zhongxiao Wan Dorrian Mah Svetlana Simtchouk Andreas Kluftinger Jonathan P. Little 《International journal of molecular sciences》2015,16(1):1221-1231
Adipose tissue secretes numerous hormone-like factors, which are known as adipokines. Adipokine receptors have been identified in the central nervous system but the potential role of adipokine signaling in neuroprotection is unclear. The aim of this study is to determine (1) Whether adipokines secreted from cultured adipose tissue of lean humans is protective against oxidative stress-induced neurotoxicity in human SH-SY5Y neuronal cells; and (2) To explore potential signaling pathways involved in these processes. Adipose tissue conditioned media (ATCM) from healthy lean subjects completely prevented H2O2 induced neurotoxicity, while this effect is lost after heating ATCM. ATCM activated the phosphorylation of ERK1/2, JNK and Akt at serine 308 in SH-SY5Y cells. PD98059 (25 µM), SP600125 (5 µM) and LY29400 (20 µM) partially blocked the protective effects of ATCM against H2O2 induced neurotoxicity. Findings demonstrate that heat-sensitive factors secreted from human adipose tissue of lean subjects are protective against H2O2 induced neurotoxicity and ERK1/2, JNK, and PI3K signaling pathways are involved in these processes. In conclusion, this study demonstrates preliminary but encouraging data to further support that adipose tissue secreted factors from lean human subjects might possess neuroprotective properties and unravel the specific roles of ERK1/2, JNK and PI3K in these processes. 相似文献
104.
Andreas Winkel Wibke Dempwolf Eva Gellermann Magdalena Sluszniak Sebastian Grade Wieland Heuer Michael Eisenburger Henning Menzel Meike Stiesch 《International journal of molecular sciences》2015,16(2):4327-4342
Peri-implant infections from bacterial biofilms on artificial surfaces are a common threat to all medical implants. They are a handicap for the patient and can lead to implant failure or even life-threatening complications. New implant surfaces have to be developed to reduce biofilm formation and to improve the long-term prognosis of medical implants. The aim of this study was (1) to develop a new method to test the antibacterial efficacy of implant surfaces by direct surface contact and (2) to elucidate whether an innovative antimicrobial copolymer coating of 4-vinyl-N-hexylpyridinium bromide and dimethyl(2-methacryloyloxyethyl) phosphonate (VP:DMMEP 30:70) on titanium is able to reduce the attachment of bacteria prevalent in peri-implant infections. With a new in vitro model with semi-coated titanium discs, we were able to show a dramatic reduction in the adhesion of various pathogenic bacteria (Streptococcus sanguinis, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis), completely independently of effects caused by soluble materials. In contrast, soft tissue cells (human gingival or dermis fibroblasts) were less affected by the same coating, despite a moderate reduction in initial adhesion of gingival fibroblasts. These data confirm the hypothesis that VP:DMMEP 30:70 is a promising antibacterial copolymer that may be of use in several clinical applications. 相似文献
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107.
Jekaterina Hermane Ilona Bułyszko Dr. Simone Eichner Dr. Florenz Sasse Wera Collisi Prof. Dr. Antti Poso Emilia Schax Dr. Johanna‐Gabriela Walter Prof. Dr. Thomas Scheper Dr. Klaus Kock Prof. Dr. Christian Herrmann Dr. Pooyan Aliuos Prof. Dr. Günter Reuter Priv.‐Doz. Dr. Carsten Zeilinger Prof. Dr. Andreas Kirschning 《Chembiochem : a European journal of chemical biology》2015,16(2):302-311
Streptomyces hygroscopicus is a natural producer of geldanamycin. Mutasynthetic supplementation of an AHBA‐blocked mutant with all possible monofluoro 3‐aminobenzoic acids provided new fluorogeldanamycins. These showed strong antiproliferative activity and inhibitory effects on human heat shock protein Hsp90. Binding to Hsp90 in the low nanomolar range was determined from molecular modelling, AFM analysis and by calorimetric studies. 相似文献
108.
109.
Back Cover: Directed Divergent Evolution of a Thermostable D‐Tagatose Epimerase towards Improved Activity for Two Hexose Substrates (ChemBioChem 4/2015) 下载免费PDF全文
110.
Process Parameters Development of Selective Laser Melting of Lunar Regolith for On‐Site Manufacturing Applications 下载免费PDF全文
Miranda Fateri Andreas Gebhardt 《International Journal of Applied Ceramic Technology》2015,12(1):46-52
Selective Laser Melting (SLM) is a candidate for on‐site manufacturing as its characteristics of energy source and powder‐based fabrication process are suitable for use with in situ material. The feasibility of using lunar regolith simulant to create objects with SLM process is investigated in this study. The process parameters are optimized and multiple objects are fabricated. A qualitative chemical analysis is carried out with scanning electron microscopy using energy‐dispersive X‐ray emission. Lastly, properties such as particle size distribution, particle shape, and crystal structure of the lunar simulant powder as well as the crystallinity and hardness of the fabricated objects are investigated. 相似文献