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61.
A radiative transfer model for the coupled atmosphere-sea ice system is used to study the change in downward irradiance across the air-ice interface. Computations demonstrate that the downward solar irradiance can be significantly enhanced across the air-ice interface. The enhancement is mainly due to light in the ice that is scattered upward and then totally reflected by the air-ice interface. It depends primarily on the change in the index of refraction across this interface and the optical properties of the sea ice, but also on the direct solar and sky illumination of the interface. 相似文献
62.
Einordnung der freien ?stehenden“ Zugelemente aus Drähten zwischen Förderseilen und Spanngliedern, die Beanspruchungen der Zugelemente, ihre Konstruktionsart und ihr Tragverhalten, aus welchen sich die Anforderungen an den einzelnen Draht herleiten lassen. 相似文献
63.
Knut Hanisch 《国际钢铁研究》1980,51(9):367-370
Die Emissionsspektralanalyse eignet sich für die Drahtanalyse, wenn die Anregungsparameter optimiert werden. Es ist erforderlich, den Walzzunder durch Beizen oder mechanische Entzunderung zu entfernen. Die Eichung kann mit amtlichen Spektrometerproben erfolgen. Für alle Proben mit einem Durchmesser größer als 4 mm können die gleichen Eichkurven verwendet werden. Für geseigerte Proben wird eine besondere Probenvorbereitung vorgeschlagen. 相似文献
64.
Knut Soelberg Roy Ludvig Sigvartsen Tor Sverre Lande Yngvar Berg 《Analog Integrated Circuits and Signal Processing》1994,5(3):235-246
An analog continuous-time neural network is described. Building blocks which include the capability for on-chip learning and an example network are described and test results are presented. We are using analog nonvolatile CMOS floating-gate memories for storage of the neural weights. The floating-gate memories are programmed by illuminating the entire chip with ultraviolet light. The subthreshold operation of the CMOS transistor in analog VLSI has a very low power dissipation which can be utilized to build larger computational systems, e.g., neural networks. The experimental results show that the floating-gate memories are promising, and that the building blocks are operating as separate units; however, especially the time constants involved in the computations of the continuous-time analog neural network should be studied further. 相似文献
65.
66.
Hannah C. Nerl Anuj Pokle Lewys Jones Knut Müller‐Caspary Karel H. W. van den Bos Clive Downing Eoin K. McCarthy Nicolas Gauquelin Quentin M. Ramasse Ivan Lobato Dermot Daly Juan Carlos Idrobo Sandra Van Aert Gustaaf Van Tendeloo Stefano Sanvito Jonathan N. Coleman Clotilde S. Cucinotta Valeria Nicolosi 《Advanced functional materials》2019,29(37)
The fabrication of 2D systems for electronic devices is not straightforward, with top‐down low‐yield methods often employed leading to irregular nanostructures and lower quality devices. Here, a simple and reproducible method to trigger self‐assembly of arrays of high aspect‐ratio chiral copper heterostructures templated by the structural anisotropy in black phosphorus (BP) nanosheets is presented. Using quantitative atomic resolution aberration‐corrected scanning transmission electron microscopy imaging, in situ heating transmission electron microscopy and electron energy‐loss spectroscopy arrays of heterostructures forming at speeds exceeding 100 nm s?1 and displaying long‐range order over micrometers are observed. The controlled instigation of the self‐assembly of the Cu heterostructures embedded in BP is achieved using conventional electron beam lithography combined with site specific placement of Cu nanoparticles. Density functional theory calculations are used to investigate the atomic structure and suggest a metallic nature of the Cu heterostructures grown in BP. The findings of this new hybrid material with unique dimensionality, chirality, and metallic nature and its triggered self‐assembly open new and exciting opportunities for next generation, self‐assembling devices. 相似文献
67.
Marius Keunecke Fryderyk Lyzwa Danny Schwarzbach Vladimir Roddatis Nicolas Gauquelin Knut Müller‐Caspary Johann Verbeeck Sara J. Callori Frank Klose Markus Jungbauer Vasily Moshnyaga 《Advanced functional materials》2020,30(18)
Heterostructures of strongly correlated oxides demonstrate various intriguing and potentially useful interfacial phenomena. LaMnO3/SrMnO3 superlattices are presented showcasing a new high‐temperature ferromagnetic phase with Curie temperature, TC ≈360 K, caused by electron transfer from the surface of the LaMnO3 donor layer into the neighboring SrMnO3 acceptor layer. As a result, the SrMnO3 (top)/LaMnO3 (bottom) interface shows an enhancement of the magnetization as depth‐profiled by polarized neutron reflectometry. The length scale of charge transfer, λTF ≈2 unit cells, is obtained from in situ growth monitoring by optical ellipsometry, supported by optical simulations, and further confirmed by high resolution electron microscopy and spectroscopy. A model of the inhomogeneous distribution of electron density in LaMnO3/SrMnO3 layers along the growth direction is concluded to account for a complex interplay between ferromagnetic and antiferromagnetic layers in superlattices. 相似文献
68.
Scientometrics - This paper introduces the concept of standard-relevant publications, complementary to standard-essential patents and framed by the concept of knowledge utilization. By analyzing... 相似文献
69.
A set of monolithic stationary phases representing a broad span of monomers and porogens have been characterized directly in their capillary chromatographic format by computational assessment of their pore structure from transmission electron micrographs obtained after in situ embedment of the monoliths in contrast resin, followed by dissolution of the fused-silica tubing, further encasement of the resin-embedded monolith, and microtomy. This technique has been compared to mercury intrusion, a more conventional technique for macroporosity estimation. Supplementing the embedding resin by lead methacrylate gave a negative staining, and the resulting micrographs showed a good contrast between the polymeric monoliths and the embedding resin that allowed studies on the pore formation and polymer development. The technique was also applied to a commercial monolithic silica column. 相似文献
70.
Assessment of the Moderate-Resolution Imaging Spectroradiometer algorithm for retrieval of aerosol parameters over the ocean 总被引:1,自引:0,他引:1
The Moderate Resolution Imaging Spectroradiometer aerosol algorithm over the ocean derives spectral aerosol optical depth and aerosol size parameters from satellite measured radiances at the top of the atmosphere (TOA). It is based on the adding of apparent optical properties (AOPs): TOA reflectance is approximated as a linear combination of reflectances resulting from a small particle mode and a large particle mode. The weighting parameter eta is defined as the fraction of the optical depth at 550 nm due to the small mode. The AOP approach is correct only in the single scattering limit. For a physically correct TOA reflectance simulation, we create linear combinations of the inherent optical properties (IOPs) of small and large particle modes, in which the weighting parameter f is defined as the fraction of the number density attributed to the small particle mode. We use these IOPs as inputs to an accurate multiple scattering radiative transfer model. We find that reflectance errors incurred with the AOP method are as high as 30% for an aerosol optical depth of 2 at 550 nm. The retrieved optical depth has a relative error of up to 8%, and the retrieved fraction eta has an absolute error of approximately 6%. We show that the use of accurate radiative transfer simulations and a bimodal fraction f yields accurate values for the retrieved optical depth and the fraction f. 相似文献