large scale synthesis of carbon nanotubes by pyrolysis

... removal of the surfactants from the mesolamellar precursors resulted in WO3 nanorods in large quantity [26] Recently, the synthesis of WO3 nanorods at a large scale [27] has been described by the ... process which allows the synthesis of large amounts of multiwalled nanotubes (MWNTs) A HRTEM image of one such representative MWNT is shown in Fig 4c The interlayer spacing of 0.65 nm between the ... top of the inner MWNT This could be explained by the formation of WS2 in the vapour phase followed by the growth of WS2 layers on the preexisting WS2 nanotubes When the reduction period of WO3...

Ngày tải lên: 19/03/2014, 16:48

... produced by pyrolysis of mixture of Si and SiO powders Recently, Pan et al [8] have developed a molten gallium-catalyzed vapor–liquid– solid (VLS) process for the growth of bundles of highly ... production of large- quantities of high-purity (no metal catalysis contamination) and ultralong (millimeters) SiO2 nanowires (most of the wires have uniform diameters of $50 nm, while some of them ... production of aligned carbon nanotubes [9,10] In comparison with the observation by Wang et al [7,8], the present growth of aligned SiO2 nanowires A simple method based on thermal oxidation of Si...

Ngày tải lên: 16/03/2014, 15:03

... hydrothermal route to a large- scale synthesis of uniform single-crystalline nanowires of hexagonal tungsten trioxide without any templates or catalysts The electrochemical performances of the as-prepared ... curves of the electrode made of as-prepared h-WO3 nanowires at the current density of 50 mA gÀ1 and 20 1C In summary, we have exploited a low-temperature solution-based method to large- scale synthesis ... increases of the amount of sulfate from 0.5 to 1.0 g (Figs and 9) Excess amounts of the sulfate had no obvious effect on the wire morphology and crystal form The details of the effect of sulfate...

Ngày tải lên: 20/03/2014, 13:04

... Catalyzing Growth of Single-Walled Carbon Nanotubes on Substrates Nano Lett 2006, 6:2987 17 Lu C, Liu J: Controlling the Diameter of Carbon Nanotubes in Chemical Vapor Deposition Method by Carbon Feeding ... S, Wardle BL: Nanoscale Zirconia as a Nonmetallic Catalyst for Graphitization of Carbon and Growth of Single- and Multiwall Carbon Nanotubes J Am Chem Soc 2009, 131:12144 33 Bystrzejewski M, Bachmatiuk ... Rümmeli et al Nanoscale Research Letters 2011, 6:303 http://www.nanoscalereslett.com/content/6/1/303 Page of 49 Rao F, Li T, Wang Y: Growth of “all -carbon single-walled carbon nanotubes from diamonds...

Ngày tải lên: 21/06/2014, 04:20

... temperature synthesis of VA-CNTs Large- scale Monte Carlo simulations [37] of SWNT synthesis showed that PECVD methods were more suitable for low temperature synthesis and had two orders of magnitude ... evolution of the graphitization of SWNTs synthesis due to reactive ion-etching effects The growth kinetics of SWNTs was monitored using Raman spectroscopy whereby the degree of graphitization of SWNTs ... micrograph of linear carbon chains (indicated by red arrows) encapsulated within a singlewalled carbon nanotubes graphite flakes were attached on the exterior of VA-CNTs for prolonged synthesis...

Ngày tải lên: 21/06/2014, 07:20

... Fig Dependence of carbon yield on the reaction temperature be through the precipitation of carbon in the form of MWNTs from the molten catalytic particles The melting temperatures of the alloy-C ... through hydrogen decrepitation route by performing several cycles of hydrogenation/dehydrogenation of the alloy using a Seiverts apparatus [17] The growth of carbon nanostructures has been carried ... SWNTs are of larger diameter of around nm Alloy filling inside SWNTs was not observed The carbon yield during the deposition has been calculated as described previously [17] and a dependence of the...

Ngày tải lên: 22/06/2014, 22:20

Ngày tải lên: 14/11/2014, 12:32

... agglomerated clusters consisting of high density of nanowires The magnified view of a single cluster is depicted in the inset of Fig 2(d) These observations suggest that growth of nanowires in the present ... diffusion of Si/SiOx vapors into the metal particles, (ii) formation of liquid droplet of metal and Si/SiOx and (iii) the precipitation in the form of solid nanowires after super-saturation of liquid ... confirmed by the investigations of the white spongy material deposited on the inner surface of the quartz tube and also on the alumina sample holder Fig 2(d) shows the low-magnification SEM image of...

Ngày tải lên: 16/03/2014, 15:18

... shown in the results and are coated by plenty of amorphous carbons Conclusions A temperature window of SWCNTs growth by catalytic chemical vapor deposition of CH4 over Mo-Fe/MgO catalyst has been ... multi-walled carbon nanotubes (MWCNTs) and organized carbon in the sample The relatively high intensity of the D band relative to G band (ID/IG = 0.72) indicates mass amorphous carbon content ... coated by more and more amorphous carbons, and when the temperature increases to 950 °C, SWCNTs are hardly observed In order to study the influence of growth temperature on the purity of prepared...

Ngày tải lên: 22/06/2014, 00:20

... clustering with a vocabulary that is large enough to cover the many named entities required to improve the accuracy of NER is difficult We enabled such large- scale clustering by parallelizing the clustering ... and, in terms of execution speed, may Acknowledgements: This corpus was provided by Dr Daisuke Kawahara of NICT To be precise, we need two copies of these Each node has a copy of the training ... “type”, or it ended with “name” followed by of This rule is for treating expressions like “ is one of the landlocked countries.” By applying this method of extraction to all the articles in Wikipedia,...

Ngày tải lên: 20/02/2014, 09:20

... coated carbon grew to become large carbon sheets, as shown in the bottom image in Fig 4b Even the nanowires were completely carbonized and mixed into a lot of carbon sheets to form a mixture of Fig ... formed by carbon atoms di€using into the Si NWs, CNTs could not be formed very well on the surface of nanowires because of both the volume change of the nanowires and breaking of the carbon network ... high (b1100°C), a mixture of graphitic carbon and SiC nanowires was formed because of both the carbonization of the nanowires and the fast carbon deposition to form the carbon- like structure Conclusions...

Ngày tải lên: 16/03/2014, 15:04

... crystallinity of the primary nanorods The degree of fusion of the primary nanorods in the bundles shows a gradual increase from the top to the base of the bundles Fig 4(e) shows a HRTEM image of the ... Ostwald-ripening process To the best of our knowledge, this is the first time that the observation of large- area uniform double-sided nanorod arrays formed by self-assembly and fusion of urchin-like nanostructures ... composed of a number of smaller nanorods with a diameter of about 20 nm Therefore, they will be referred to as nanorod bundles hereafter We also performed FE-SEM observation on a cross-section of the...

Ngày tải lên: 20/03/2014, 13:04

... Edge of NC-70, (d) Edge of NC-80 Figure Particle size distribution of carbon/ water nanofluid weighing after drying at fixed weight of nanofluid and calculated by Eq 1, and the density of carbon ... Schematic diagram of the synthesis system for carbon/ water nanofluid (a) The synthesis system for carbon/ water nanofluid (b) The vaporization chamber in the synthesis system Teng et al Nanoscale Research ... conducted an examination of the collected nanofluids material properties Preparation of carbon/ water nanofluid by plasma arc The carbon/ water nanofluid in this study was prepared by the plasma arc system...

Ngày tải lên: 21/06/2014, 04:20

... parameter The synthesis of MWCNTs by CVD often involves three main steps: (1) decomposition of hydrocarbon gas at the surface of the catalyst nanoparticles; (2) diffusion of resultant carbon atom ... liberate carbon atoms The change of elastic energy and surface energy of the carbon layer caused the radius of curvature of the Ni catalyst particle to become small The rising gradient of the surface ... presence of H2 can be explained by its gasification effect [23] H2 is beneficial to keep the exposed surface clean of carbon and prevent catalyst deactivation [24] The size and distribution of these...

Ngày tải lên: 22/06/2014, 01:20

... the amorphous carbon on the surface of the nanotubes Specifically, by using this gas condition to conduct the plasma treatment, the highest concentration of 31.1% (after exposure) of oxygenated ... comparison purposes In contrast to the spectrum of the pristine MWCNTs, a higher concentration of oxygen is introduced to the surface of the nanotubes treated by the ECR plasma using any gas composition ... number of carbon atoms detected As shown in Fig and Table 1, after the samples are treated by the plasma treatment, the XPS measurements show that the concentrations of the graphite, sp3 carbons,...

Ngày tải lên: 22/06/2014, 01:20

... satisfaction of the dissertation requirements for the degree of Doctor of Philosophy January 2006 Prof Hiroshi Matsui Date Chair of Examining Committee January 2006 Prof Gerald Koeppl Date Executive Officer ... THE CITY UNIVERSITY OF NEW YORK ii Abstract SYNTHESIS OF INORGANIC NANOWIRES BY USING PEPTIDE NANOTUBES AS THE TEMPLATES VIA BIOLOGIC RECOGNITION by Lingtao Yu Adviser: Professor Hiroshi Matsui ... inner cylinder and large surface area of carbon nanotubes may make it possible for them to be the next generation of hydrogen storage system for the hydrogen fuel cell Carbon nanotubes also have...

Ngày tải lên: 13/11/2014, 16:27

... Chapter 12 Large- Scale Synthesis of Carbon Nanotubes by Pyrolysis K Tanaka, M Endo, K Takeuchi, W -K Hsu, H W Kroto, M Terrones and D R M Walton 143 Chapter 13 Carbon Nanotubes as a Novel It-Electron ... dependence of@ e structure of EELS on the diameter and the anisotropic features of CNTs Introduction - Morphological Features of CNTs Since the discovery of carbon nanotubes (CNTs) [I], most of the ... Fukui Chapter Synthesis and Purification of MultiWalled and Single-Walled Carbon Nanotubes M.Yumura Chapter Electron Diffraction and Microscopy of Carbon Nanotubes S Amelinckx,...

Ngày tải lên: 05/03/2014, 17:20

... Biogenesis of cytochrome c¢ Heterologous synthesis of PHCP by E coli The E coli System I cytochrome c biogenesis machinery, consisting of the Dsb and Ccm proteins, is responsible for the synthesis of ... addition, the effects of Dsb proteins on cytochrome c¢ synthesis have not been examined to date In this study, we examined the heterologous synthesis of cytochrome c¢ proteins by E coli strains deficient ... necessarily required for the heterologous synthesis of the PHCP protein by E coli, unlike that of class I cytochromes c, including the PH c552 protein Spectral properties of the authentic PHCP protein Similarity...

Ngày tải lên: 06/03/2014, 00:20

... dictionary of derived nominals In Proc of RANLP, Tzigov Chark, Bulgaria C Manning 1993 Automatic Acquisition of a Large Subcategorization Dictionary from Corpora In Proc of the 31st Meeting of ACL, ... is the NP of the PP The only part of the feature structure which is not represented by the GRs is coindexation between the omitted direct object of the VP-complement and the subject of the whole ... including additional frames found by manual inspection of unclassifiable examples during development of the classifier These consisted of e.g some occurrences of phrasal verbs with complex complementation...

Ngày tải lên: 17/03/2014, 04:20

... properties of the arguments of the verb giefien (water) in example (1) of Section (2.1) above are captured by the following semantic type: (13) CONTENT value of giefien m i t giefien-ch-ofst-rel ... both changes of state and changes of location The locative alternant of the verb giefien (example (2) of Section (2.1)) denotes only a simple change of location This is captured by the following ... rule approaches to verbal alternations in particular and to development of (the lexicon of) large- scale computational grammars of natural language based on HPSG in general As an dmtc stands for directed_motion_to_contact...

Ngày tải lên: 17/03/2014, 22:20