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排序方式: 共有802条查询结果,搜索用时 15 毫秒
721.
Self‐Suspended Nanomesh Scaffold for Ultrafast Flexible Photodetectors Based on Organic Semiconducting Crystals 下载免费PDF全文
Lei Zhang Nadiia Pasthukova Yifan Yao Xiaolan Zhong Egon Pavlica Gvido Bratina Emanuele Orgiu Paolo Samorì 《Advanced materials (Deerfield Beach, Fla.)》2018,30(28)
Self‐standing nanostructures are of fundamental interest in materials science and nanoscience and are widely used in (opto‐)electronic and photonic devices as well as in micro‐electromechanical systems. To date, large‐area and self‐standing nanoelectrode arrays assembled on flexible substrates have not been reported. Here the fabrication of a hollow nanomesh scaffold on glass and plastic substrates with a large surface area over 1 mm2 and ultralow leakage current density (≈1–10 pA mm?2 @ 2 V) across the empty scaffold is demonstrated. Thanks to the continuous sub‐micrometer space formed in between the nanomesh and the bottom electrode, highly crystalline and dendritic domains of 6,13‐bis(triisopropylsilylethinyl)pentacene growing within the hollow cavity can be observed. The high degree of order at the supramolecular level leads to efficient charge and exciton transport; the photovoltaic detector supported on flexible polyethylene terephthalate substrates exhibits an ultrafast photoresponse time as short as 8 ns and a signal‐to‐noise ratio approaching 105. Such a hollow scaffold holds great potential as a novel device architecture toward flexible (opto‐)electronic applications based on self‐assembled micro/nanocrystals. 相似文献
722.
JF Conway N Cheng A Zlotnick SJ Stahl PT Wingfield DM Belnap U Kanngiesser M Noah AC Steven 《Canadian Metallurgical Quarterly》1998,279(5):1111-1121
Hepatitis B virus capsid protein comprises a 149 residue "assembly" domain that polymerizes into icosahedral particles, and a 34 residue RNA-binding "protamine" domain. Recently, the capsid structure has been studied to resolutions below 10 A by cryo-electron microscopy, revealing much of its alpha-helical substructure and that it appears to have a novel fold for a capsid protein; however, the resolution is still too low for chain-tracing by conventional criteria. Aiming to establish a fiducial marker to aid in the process of chain-tracing, we have used cryo-microscopy to pinpoint the binding site of a monoclonal antibody that recognizes the peptide from residues 78 to 83. This epitope resides on the outer rim of the 30 A long spikes that protrude from the capsid shell. These spikes are four-helix bundles formed by the pairing of helix-turn-helix motifs from two subunits; by means of a tilting experiment, we have determined that this bundle is right-handed. Variants of the same protein present two clinically important and non-crossreactive antigens: core antigen (HBcAg), which appears early in infection as assembled capsids; and the sentinel e-antigen (HBeAg), a non-particulate form. Knowledge of the binding site of our anti-HBcAg antibody bears on the molecular basis of the distinction between the two antigens, which appears to reflect conformational differences between the assembled and unassembled states of the capsid protein dimer, in addition to epitope masking in capsids. 相似文献
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Ohne Zusammenfassung 相似文献
726.
727.
Bützler Festetics Lindner Nüsslein Spittler und Stahl 《Zeitschrift für Jagdwissenschaft》1979,25(3):186-192
Ohne Zusammenfassung 相似文献
728.
Henrik Stahl Gaylord Smith Sophie Wastiaux 《Journal of Failure Analysis and Prevention》2001,1(1):51-54
This case study demonstrates that Alloy 601 (UNS N06601) is susceptible to strain-age cracking. The observation illustrates
the potential importance of post weld heat treatment to the successful utilization of
this alloy in certain applications. 相似文献
729.
Maria Cristina Polidori Juan-Carlos Carrillo Pablo E Verde Helmut Sies Johannes Siegrist Wilhelm Stahl 《Nutrition journal》2009,8(1):10-4
To explore the effects of increasing fruit and vegetable intake and the resulting effects on levels of circulating micronutrients
in a community-dwelling population with an already high consumption of fruits and vegetables, 112 volunteers (86% women) underwent
targeted dietary counseling for three months. At the beginning of the study and after 4, 8 and 12 weeks a food frequency questionnaire
was filled in, and plasma levels of dietary antioxidants as well as biomarkers of oxidative lipid and protein damage were
determined. Compared to baseline, especially the intake of fruits was significantly improved after 3 months of intervention,
and mean plasma levels of lutein, zeaxanthin, β-cryptoxanthin, lycopene, α- and β-carotene, retinol, α-tocopherol, vitamin
C and vitamin B6 were increased. Biomarkers of oxidative stress remained unchanged. Thus, a nutritional counseling program
is capable of improving plasma levels of antioxidants even in a health-conscious population. A decrease in biomarkers of oxidative
stress, however, does not occur. 相似文献
730.
In the last 15 years several procedures have been developed that can find solutions of acceptable quality in reasonable computing
time to Job Shop Scheduling problems in environments that do not involve sequence-dependent setup times of the machines. The
presence of the latter, however, changes the picture dramatically. In this paper we adapt one of the best known heuristics,
the Shifting Bottleneck Procedure, to the case when sequence dependent setup times play an important role. This is done by
treating the single machine scheduling problems that arise in the process as Traveling Salesman Problems with time windows,
and solving the latter by an efficient dynamic programming algorithm. The model treated here also incorporates precedence
constraints, release times and deadlines. Computational experience on a vast array of instances, mainly from the semiconductor
industry, shows our procedure to advance substantially the state of the art.
Paper presented in New York at MISTA 2005.
E. Balas supported by the National Science Foundation through grant DMI-9802773 and by the Office of Naval Research through
contract #N00014-97-1-0133. 相似文献