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111.
Young Jin Sa Chiyoung Park Hu Young Jeong Seok‐Hee Park Zonghoon Lee Kyoung Taek Kim Gu‐Gon Park Sang Hoon Joo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(16):4186-4190
A facile, scalable route to new nanocomposites that are based on carbon nanotubes/heteroatom‐doped carbon (CNT/HDC) core–sheath nanostructures is reported. These nanostructures were prepared by the adsorption of heteroatom‐containing ionic liquids on the walls of CNTs, followed by carbonization. The design of the CNT/HDC composite allows for combining the electrical conductivity of the CNTs with the catalytic activity of the heteroatom‐containing HDC sheath layers. The CNT/HDC nanostructures are highly active electrocatalysts for the oxygen reduction reaction and displayed one of the best performances among heteroatom‐doped nanocarbon catalysts in terms of half‐wave potential and kinetic current density. The four‐electron selectivity and the exchange current density of the CNT/HDC nanostructures are comparable with those of a Pt/C catalyst, and the CNT/HDC composites were superior to Pt/C in terms of long‐term durability and poison tolerance. Furthermore, an alkaline fuel cell that employs a CNT/HDC nanostructure as the cathode catalyst shows very high current and power densities, which sheds light on the practical applicability of these new nanocomposites. 相似文献
112.
Nakyung Hwang Jongguen Lee Dae Hoon Lee Young-Hoon Song 《Plasma Chemistry and Plasma Processing》2012,32(2):187-200
The interactive phenomena between a rotating arc and a premixed methane/air flame have been investigated. The effects of the
rotating arc on the flame were observed: both lean and rich flammability limit was extended with the rotating arc on. More
interestingly, the opposite interactions, i.e., the effects of the flame on the rotating arc, were also observed: the arc
length, angular speed, and electrical characteristics are affected by the flame. An analysis of the optical emission spectra
showed that the rotating arc generates chemically active species such as excited N2 molecules and O and H atoms. An analysis of the gas products indicated that the concentrations of the major gas products
such as CO2, CO, and H2 were not significantly affected by the rotating arc, although the flammability limit are significantly extended. Unlike these
major gas products, minor products like NOx emissions increased by an order of magnitude in the presence of a rotating arc under certain air/fuel conditions. 相似文献
113.
In this paper, we give an answer to a long-standing open question on the lifting problem for commuting subnormals (due to A. Lubin): The subnormality for the sum of commuting subnormal operators does not guarantee the existence of commuting normal extensions. 相似文献
114.
Kim Gun Gyun Lee Jun Young Choi Pyeong Seok Vyas Chirag K. Yang Seung Dae Hur Min Gu Park Jeong Hoon 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(3):1099-1106
Journal of Radioanalytical and Nuclear Chemistry - Accumulation of triphenylphosphonium (TPP) is normally observed in the mitochondria from the extracellular spaces due to the high difference in... 相似文献
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A low-dynamic tone-compression technique is developed for realistic image rendering that can make three-dimensional (3D) images similar to realistic scenes by overcoming brightness dimming in the 3D display mode. The 3D surround provides varying conditions for image quality, illuminant adaptation, contrast, gamma, color, sharpness, and so on. In general, gain/offset adjustment, gamma compensation, and histogram equalization have performed well in contrast compression; however, as a result of signal saturation and clipping effects, image details are removed and information is lost on bright and dark areas. Thus, an enhanced image mapping technique is proposed based on space-varying image compression. The performance of contrast compression is enhanced with complex adaptation in a 3D viewing surround combining global and local adaptation. Evaluating local image rendering in view of tone and color expression, noise reduction, and edge compensation confirms that the proposed 3D image-mapping model can compensate for the loss of image quality in the 3D mode. 相似文献
117.
We analyse the use of options for online advertisement publishers. By providing a discount or rewards to advertisers, publishers can utilise their uncertain service capacity, page-views, more efficiently. We use Generalised Nash Bargaining to study the feasibility of the option contract and solve for an optimal value for the option price. We compare the revenues and benefits from advertisements under the option contract, with those without the options using numerical studies. We also study the impact of pricing and other components in the game on the optimal option price, the publisher's revenues, and the advertiser's benefits from the advertisements. 相似文献
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