behaviour of single walled carbon nanotubes in magnetic fields

... [19] Single- walled carbon nanotubes (SWCNTs, 30–40 wt% 767 purity) were obtained from Hanwha Nanotech Co., LTD, Seoul, Korea (http://hnt.hanwha.co.kr/) Instrumentation Fourier-transform infrared ... samples were imbedded in KBr disks Elemental analysis (EA) was performed by using a CE Instruments EA1110 The melting points (mp) were determined on a Mel-Temp melting point apparatus and are ... was conducted both in air and nitrogen atmospheres with a heating rate of 10 °C/min using a Perkin–Elmer TGA7 The field emission scanning electron microscopy (FE-SEM) used in this work was a LEO...

Ngày tải lên: 22/06/2014, 00:20

... imaging of single- walled carbon nanotubes J Luminesc 2006, 119-120:204 10 Hartschuh A, Qian H, Meixner AJ, Anderson N, Novotny L: Nanoscale Optical Imaging of Excitons in Single- Walled Carbon Nanotubes ... breathing mode; SWCNT: single- walled carbon nanotubes; TERS: tip-enhanced Raman spectroscopy Acknowledgements We gratefully acknowledge financial support from the DFG Cluster of Excellence “Unifying ... diameter-dependent, and the resonance window is much wider Indeed, when plotting the G+ and G- intensities as a function of the bundle height, we observe an increased intensity with increasing height (see Figure...

Ngày tải lên: 21/06/2014, 05:20

... temperature was raised to the setting value in Ar atmosphere at a flow rate of 200 mL/min before CH4 was introduced into the reactor at 60 mL/min for 30 min, then CH4 was turned off and the furnace was ... the ID/IG increases with growth temperature In the former stage, SWCNTs are formed gradually with increasing growth temperature and the content of SWCNTs in the products increases In the latter ... about 900 °C Fig In uence of growth temperature on the resulting intensity ratio ID/IG 123 Acknowledgement The authors thank the support of Natural Science Foundation of Linyi, China Nanoscale...

Ngày tải lên: 22/06/2014, 00:20

... Department of Electronic Engineering, University of Seoul, Seoul, Korea, in 1988, and the Ph.D degree in semiconductor engineering from Korea University, Seoul, in 1995 In 1988, he joined the Korea Institute ... Eklund, Debundling and dissolution of single- walled carbon nanotubes in amide solvents, J Am Chem Soc 126 (2004) 6095–6105 N Sano, F Ohtsuki, Carbon nanohorn sensor to detect ozone in water, J Electrost ... Department of Mechanical Engineering, Swansea University, United Kingdom Since then, he joined Korea University as a research professor His recent interests include patterning of nanoscale structures...

Ngày tải lên: 19/03/2014, 16:47

... difference in energy between the singlet and doublet states The + sign means the triplet state has lower energy than the singlet state Fig (a) Optimized structure of C68B2 armchair single walled carbon ... optimized structure of zig-zag C68B2 single walled carbon nanotube Methods and Results The structures at minimum energy of zig-zag (7,0) and armchair (5,5) tubes are obtained using the Hartree Fock ... (2007) 2:447–449 Table Calculated total energy of singlet and triplet state for boron and nitrogen doped single wall zig-zag and armchair carbon nanotubes Formula Type C68B2 Armchair Method Total...

Ngày tải lên: 22/06/2014, 18:20

... analysis (TGA) (TA-500) was applied to investigate the changes in thermal stability with a heating rate of 10 °C/min and an air flow of 60 mL/min Raman spectroscopy (Jobin YVON LabRam HR800) was used ... distributions of the sample not show any observable difference in comparison with those of the pristine sample In contrast to Fig 2b, the TEM image in Fig 2d shows that the dispersion ability of the nanotubes ... compositions to C 1s intensity for 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...

Ngày tải lên: 22/06/2014, 01:20

... achiral carbon nanotubes can be decomposed in the following way [17]: To determine the symmetries at the C point of the 12 N (N is the number of unit cells in the tube and N = n for ZZ-1 BC2N nanotubes) ... according to the following irrep’s: CZZÀ1 ¼ CZZÀ1  Cv 12N e GzzÀ1 ½nŠ ¼ Cnh ð15Þ To determine the symmetries (at the C point) of the 12 N (N = n) phonons in AC-1 BC2N nanotubes and the number of ... of BC2N nanotubes were discussed based on line group All BC2N nanotubes possess nonsymmorphic line groups, just like carbon nanotubes [8] and boron nitride nanotubes [11] Contrary to carbon and...

Ngày tải lên: 22/06/2014, 01:20

... air and scanning in the 2h range of 10–90°, in steps of 0.05° X-ray diffraction pattern of DyNi2 alloy shows the formation of single phase with a C 15 type cubic structure XRD pattern of as-prepared ... fully carbon based field emitter by spin coating a solution of MWNT over graphitized carbon paper In this paper we report the fabrication of both asgrown and purified MWNT based field emitters by spin ... burning of MWNT Final residual weight of 1.5% was obtained for the purified MWNT The purity of the purified sample is about 95% whereas the TG curve for the as-grown MWNT indicates a purity of only...

Ngày tải lên: 22/06/2014, 18:20

... results indicated an in increase in the transformation capacity of N meninigtidis in different concentrations of MWCNT when compared with negative control without nanotubes A final analysis of the interaction ... Hajj-associated outbreak strain of Neisseria meningitidis serogroup W135: estimates of the attack rate in a defined population and the risk of invasive disease developing in carriers Clin Infect Dis 2003, ... of multi -walled carbon nanotubes The carbon nanotubes were produced by the process of hot filament chemical vapor deposition (HFCVD), at the Nanoengineering and Diamond Laboratory (NanoEng) of...

Ngày tải lên: 11/08/2014, 08:20

... hybridized carbon atoms (C-C distance is about 1.4 Ǻ) The wall of CNTs is single or multiple layers of graphene sheets, of which those formed by rolling up of single sheet are called single- walled carbon ... thinking Because of the synthesis impairment, acetylcholine is decreased in the neurons in the Alzheimer disease brain, leading to the incapability of learning, memory, and thinking Providing ... energy of singlewalled carbon nanotubes Appl Phys Lett 1999, 16:2307-2309 Peigney A, Laurent C, Flahaut E, Bacsa RR, Rousset A: Specific surface area of carbon nanotubes and bundles of carbon nanotubes...

Ngày tải lên: 20/06/2014, 22:20

... conductance minima Abbreviations CNTs: carbon nanotubes; MWCNTs: multi -walled carbon nanotubes; PMMA: poly(methyl methacrylate); SWCNTs: single- walled carbon nanotubes; THF: tetrahydrofuran; XTEM: ... embedded in SiN was XTEM investigated The TEM Page of investigations, performed on nanotubes deposited directly on the carbon grid, reveal a uniform spatial extension of MWCNT network In our opinion, ... field-assisted tunneling between neighboring nanotubes embedded in SiN We assume that SiN fills up all the space in the structure The interface between the nanotubes and the SiN matrix does not...

Ngày tải lên: 21/06/2014, 06:20

... of an ALD precursor The Raman spectrum of our PECVD MWCNTs (Fig curve a) shows a strong D band, indicating the existence of defects on the tube wall Compared to MWCNTs, the surfaces of the single- walled ... configuration of the CNTs As a micromolecular form of carbon, CNT can be regarded as graphitic layers (sp2hybridized carbon atoms) rolled up into a cylindrical form A perfect CNT is chemically inert ... also originates from the disorder features due to the finite size effect of the crystalline domain or lattice distortion [18] The intensity ratio of the D0 over the G band (ID0 /IG) increases...

Ngày tải lên: 21/06/2014, 08:20

... (10 min) the same as in the prior report [20] and choose the H2 flow rate as the single parameter The synthesis of MWCNTs by CVD often involves three main steps: (1) decomposition of hydrocarbon ... observed that the higher flow rate induces the amorphization of the lattice and formation of defects in MWCNTs, indicating the decrease of the degree of disorder in MWCNTs This result is consistent ... decomposition of CH4 to 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...

Ngày tải lên: 22/06/2014, 01:20

... demonstrates that 4-aminobenzoyl moiety was covalently attached to the surface of MWNT as shown in Scheme [36] The aromatic amine groups will provide the sites for the ring opening initiation of e-caprolactam ... temperature of weight loss of the P-MWNTs occurred at 600 °C while that of the F-MWNTs occurred at 460 °C The early weight loss of the F-MWNTs could be attributed to the stripping off of aromatic amine ... represents a starting point of a three-dimensional MWNT network in the matrix, and can be determined from the starting / at which the viscosity does not show Newtonian but shear-thinning behavior...

Ngày tải lên: 22/06/2014, 01:20

... inner tubes The continuously switching between two electronic states can be attributed to the locally orientational depinning or melting of a small part of inner tube at certain temperature (TOM, ... curves of a metallic DWCNT recorded around 9.9 K continuously indicate that there are multi-stable conductance states in this tube Inset: Linear conductance of the DWCNT as a function of temperature ... determined the current-carrying capacity of each wall of DWCNTs by breaking down their wall sequentially under high bias voltages In this paper, we present electrical transport properties of individual...

Ngày tải lên: 22/06/2014, 01:20

... properties of single- walled carbon nanotubes Nature, 391(6662), 62–64 Santos, C.V., Hernandez, A.L.M., Fisher, F.T., Ruoff, R & Castano, V.M (2003) Improvement of thermal and mechanical properties of carbon ... bridges”, connecting the PANI conducting domains A further increase in conductivity was observed for PANI/MWCNTs-MnO2, which may be due to the role of MnO2 in stabilising the interaction between ... PANI/MWCNTs-MnO2 TEM images of the MWCNTs after being filled with MnO2 are shown in Figure 4(a) The filled MWCNTs show dark contrast, suggesting that the filling of MnO2 in the inner cavity of MWCNTs did take...

Ngày tải lên: 07/08/2014, 14:20

... that single gel bands contain high numbers of bound proteins Nevertheless, characteristic proteins could be assigned to the bands by including the number of detected peptides and excluding proteins ... or binding protein [52] Specifically bound to MWCNT-COOH was Keratin 6A (a constituent protein of the intermediate filaments) and the coagulation factor XI (Figure 1C) (involved in the intrinsic ... Linse S: Understanding the nanoparticle-protein corona using methods to quantify exchange rates and affinities of proteins for nanoparticles Proceedings of the National Academy of Sciences of...

Ngày tải lên: 11/08/2014, 00:22

... images of pristine single- walled (a) and multiwalled carbon nanotubes (b) Several methods for the production of both types of tubes and the modulation of their dimensions are available in the ... possibility of linking a large number of biomolecules to the surface of the tubes 2.3 Carbon Nanotube Cell Uptake: Mechanisms and Trafficking Determination of the exact mechanism leading to cellular internalisation ... is the main problem in achieving patient-friendly routes of administration of this drug The results of this work showed that the use of CNTs as adsorbent, combined with casein as enzyme inhibitor...

Ngày tải lên: 17/02/2014, 05:20

... contribution of these amino acids interacting with the pyrimidine ring to the catalysis of E coli CMP kinase Substitution of the side chain from a well-structured protein can have two types of consequence: ... different time intervals, aliquots were withdrawn and diluted in buffer containing 10 lgặmL)1 of soybean trypsin inhibitor The rst-order rate constant of inactivation of CMP kinase by TPCK-trypsin was ... bicarbonate a small proportion of dimers were formed, even in the case of the wild-type protein as indicated by ESI-MS or SDS PAGE in the absence of reducing agents The proportion of dimers increased...

Ngày tải lên: 16/03/2014, 10:20

... ‘‘pitting’’ corrosion [36]) For Ti as a substrate, the formation of TiO2 nanotubes in ClOÀ containing solution is possible over a broad range of the experimental conditions Bundles of nanotubes ... images of nanoporous WO3 prepared in ClOÀ and ClÀ containing electrolytes In this case, bundles of WO3 nanopore structures show an average pore diameter of 40 nm, and a structure length of 16 ... clear that using potential steps in perchlorate or chloride containing electrolytes, passivity breakdown conditions could be established – the latter being in line with extended Fig (continued ) 950...

Ngày tải lên: 20/03/2014, 13:06