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Binderless carbon nanotubes aerogel (CNAG) composites represent a new class of high-performing electrodes for energy storage
applications such as electrochemical double layer capacitors. The composites developed here differ significantly from these
previously prepared with dispersion processes. The CNAG material was prepared by a molding procedure that is the synthesis
by a chemical vapor deposition method to grow carbon nanotubes directly onto a microfibrous carbon paper substrate. Then the
carbon aerogel is synthesized on the carbon nanotubes. The key feature of the method is eliminating the need of controlling
the carbon nanotube concentration, which permits optimized dispersion processes to reinforce the aerogel's networks. The CNAG
electrode delivered very high specific capacitances of 524 F g−1 in KOH electrolyte and 280 F g−1 in H2SO4 electrolyte. Furthermore, this better integration of carbon nanotubes in the matrix of carbon aerogel improved its resistance
to the attack by the electrolyte and conferred an excellent cycle life over 5,000 cycles of charge–discharge in both electrolytes. 相似文献
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It is well known that in a regular domain, the solutions of the Laplace equation with mixed boundary conditions can present a singular part. In this work, we prove a Carleman estimate for the two dimensional domain heat equation in presence of these singularities. 相似文献
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Jacqmin T Armijo J Berrada T Kheruntsyan KV Bouchoule I 《Physical review letters》2011,106(23):230405
We report on local, in situ measurements of atom number fluctuations in slices of a one-dimensional Bose gas on an atom chip setup. By using current modulation techniques to prevent cloud fragmentation, we are able to probe the crossover from weak to strong interactions. For weak interactions, fluctuations go continuously from super- to sub-Poissonian as the density is increased, which is a signature of the transition between the subregimes where the two-body correlation function is dominated, respectively, by thermal and quantum contributions. At stronger interactions, the super-Poissonian region disappears, and the fluctuations go directly from Poissonian to sub-Poissonian, as expected for a "fermionized" gas. 相似文献
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Bhumasamudram Jagadish Tarik J. Ozumerzifon Sue A. Roberts Gabriel B. Hall Eugene A. Mash Natarajan Raghunand 《合成通讯》2014,44(3):441-449
Alkylation of the hydrobromide salts of 1,4,7-tris(methoxycarbonylmethyl)-1,4,7,10-tetraazacyclododecane and 1,4,7-tris(ethoxycarbonylmethyl)-1,4,7,10-tetraazacyclododecane with appropriate α-bromoacetamides, followed by hydrolysis, provides convenient access to 10-(2-alkylamino-2-oxoethyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid derivatives that contain acid-sensitive functional groups. The utility of the method is demonstrated by improved syntheses of two known 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid monoamides bearing acid-sensitive ω-tritylthio alkyl chains in much greater yields based on cyclen as the starting material.
[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献