catalytic production and purification of nanotubules having fullerene scale diameters

... Res 25, 98 (1992) CATALYTIC PRODUCTION AND PURIFICATION OF NANOTUBULES HAVING FULLERENE- SCALE DIAMETERS V I[vANov,~** A FONSECA," J B.NAGY,"+LUCAS," LAMBIN," BERNAERTS~ A P D and X B ZHANG~ "Institute ... contribute to the dissemination of present understanding of the subject and to future developments in the science and technology of carbon nanotubes and fullerenes, and of carbon science more generally ... A FONSECA, J B NAGY, A LUCAS, P LAMBIN, D BERNAERTS and X B ZHANG: Catalytic production and purification of nanotubes having fullerenescale diameters ...

Ngày tải lên: 05/03/2014, 15:21

... Res 25, 98 (1992) CATALYTIC PRODUCTION AND PURIFICATION OF NANOTUBULES HAVING FULLERENE- SCALE DIAMETERS V I[vANov,~** A FONSECA," J B.NAGY,"+LUCAS," LAMBIN," BERNAERTS~ A P D and X B ZHANG~ "Institute ... contribute to the dissemination of present understanding of the subject and to future developments in the science and technology of carbon nanotubes and fullerenes, and of carbon science more generally ... A FONSECA, J B NAGY, A LUCAS, P LAMBIN, D BERNAERTS and X B ZHANG: Catalytic production and purification of nanotubes having fullerenescale diameters ...

Ngày tải lên: 27/06/2014, 17:20

... Res 25, 98 (1992) CATALYTIC PRODUCTION AND PURIFICATION OF NANOTUBULES HAVING FULLERENE- SCALE DIAMETERS V I[vANov,~** A FONSECA," J B.NAGY,"+LUCAS," LAMBIN," BERNAERTS~ A P D and X B ZHANG~ "Institute ... contribute to the dissemination of present understanding of the subject and to future developments in the science and technology of carbon nanotubes and fullerenes, and of carbon science more generally ... A FONSECA, J B NAGY, A LUCAS, P LAMBIN, D BERNAERTS and X B ZHANG: Catalytic production and purification of nanotubes having fullerenescale diameters ...

Ngày tải lên: 27/06/2014, 17:20

... sensor response, and times of adsorption/desorption of screenprinted and dip-coated films sensing a flux of 150 mL of N2 with a charge of 1% NH3 Material Fig Optical properties of: (a) dip-coated ... adsorption/desorption, and the direction and amount of charge transfer Fig Photocurrent ratio of dip-coated TiO2 –MWCNT films and TiO2 films as a function of wavelenght The spectral response of TiO2 (broken line) and ... dip-coated and screen-printed composites with their sensing performance The color and size of titania symbols are representative of the lack (white) or abundance (yellow) of Ti3+ states and of the...

Ngày tải lên: 20/03/2014, 13:07

... to 60 nm (c, d) Raman shift of the G and 2D bands, respectively The positions of both bands are shifted to higher energies The G band is around 1610 cm-1 and the 2D band around 2750 cm-1 This high ... centered at 1582 cm-1, and a 2D band at 2690 cm-1 The average up shift is then of 28 cm-1 for the G band, and of 60 (30) cm-1 for the 2D (D) band, respectively The G and 2D band Raman shift maps are ... D band lies around 1380 cm-1, the G band around 1610 cm-1, and the 2D band around 2750 cm-1 whereas neutral relaxed graphene has a D band around 1350 cm-1, a G band centered at 1582 cm-1, and...

Ngày tải lên: 21/06/2014, 05:20

... the NEGF and NEMD calculations HJL participated in the design of the study and discussions of the theoretical results YWW, HYL, and LP participated in the implementation of the LAMMPS and ATK ... Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan ... we use a combination of nonequilibrium molecular dynamics simulations and NEGF method to study the thermoelectric properties of a serial of CNTs with different diameters and chiralities They...

Ngày tải lên: 21/06/2014, 17:20

... between Ch and a1 and it varies from 00 to 300 Nanotubes having chiral angle of 00 and 300 are called zigzag and armchair, respectively, while nanotubes having chiral angles between 00 and 300 are ... of different configurations of vacancy defects, such as the number of missing atoms and the shape of defects, on the buckling properties of SWNTs and DWNTs are studied The cumulative effect of ... the buckling of defective freestanding CNTs Here, effects of different defect parameters, such as number of missing atoms, number of dangling bonds, asymmetry of defects and number of vacancy clusters,...

Ngày tải lên: 09/09/2015, 18:54

... support and great confidence in me all through these years ii Table of Contents Table of Contents ACKNOWLEDGEMENTS TABLE OF CONTENTS ABSTRACT I III VII LIST OF TABLES IX LIST OF FIGURES X LIST OF ... the tube axis, and a1 and a2 are the unit vectors of graphene in real space Fig 1.4 Schematic illustration of sp1, sp2 and sp3 hybrid carbon orbitals Fig 1.5 Illustration of energy of the electrons ... the conduction band minimum, and VBM is the valence band maximum 134 Fig 6.10 Top and cross-sectional view SEM images of composite emitters (a) and (b) 50 nm ta-C coated CNTs; (c) and (d) 50 nm...

Ngày tải lên: 11/09/2015, 10:17

... emission mass, barrier height of the emitter F is the local field, ε0 is the permittivity of free space, emitters, 21 Chapter Physics of Field Emission and t(y) and υ(y) are the Nordheim elliptic ... electron emission mechanism The slope of the linear region of the F-N plot is a function of both β and Ø, which can be expressed as below by transformation of the Eq (2.3): φ3/ Slope = −6.83 × ... low and high electrical field This deviation might be due to the space charge effects, overheating of the emitter tips or the low concentration of the carriers in the tips, conduction band of...

Ngày tải lên: 11/09/2015, 10:17

... representing the order of diffraction, λ is the wavelength, d is the interplanar spacing of the reflecting (diffracting) plane, and θ is the angle of the incidence and of the diffraction of the radiation ... measurements of the work functions and band structures of the solid, the surface and adsorbed layers [27, 28] In this study, UPS technique was used to measure the work functions of the samples Photons of ... spectrum of a mixture of elements is approximately the sum of the peaks of the individual constituents Generally, identification of chemical states can be made from exact measurements of peak...

Ngày tải lên: 11/09/2015, 10:17

... temperatures [9] However, this kind of CNTs is rather thick with their diameters correlated to the sizes of the metal catalyst particles and the graphene layers of the catalytic produced CNTs usually ... growth Therefore, the size of the catalyst particles determines the size of the as-grown CNTs, as well as their locations [4] The advantages of the catalytic growth of CNTs are that long nanotubes ... application of an alternating current controlled power supply [2, 6-8] Some of these methods are innovative and effective in CNT growth However, the main problem of these methods is the incapability of...

Ngày tải lên: 11/09/2015, 10:18

... low electron affinity and strong mechanical properties of DLC and the one-dimensional free-standing geometry of CNTs by coating the DLC thin films directly onto the surface of the vertically-aligned ... on some nanoscale field emitters and lowered threshold fields of the emitters were observed after doing so [13-15] In this project, we attempted to combine the advantages of the DLC and CNTs, i.e., ... and extraordinarily increase the lifetime of components [7] Diamond and DLC are potential in FE applications due to their low-field electron emission, hardness to withstand ion bombardment, and...

Ngày tải lên: 11/09/2015, 10:18

... Top and cross-sectional view SEM images of composite emitters (a) and (b) 50 nm sectional ta-C coated CNTs; (c) and (d) 50 nm ta coated CNTs with a 10 s hydrogenation treatment; C ta-C (e) and ... the tips of these whiskers seem to protrude out and stand freely rather than exhibiting curly shape at the tips like the pristine ta-C coated CNTs With 20 s hydrogenation, the surface of the sample ... thin films, which look like a layer of whiskers formed with the average diameter larger than that of the pristine CNTs and the whiskers extended from the tips of the CNTs With a 10 s surface hydrogenation...

Ngày tải lên: 11/09/2015, 10:18

... Illustration of the band bending of the ta-C film in equilibrium with the absorbed water layer in air Evac represents the vacuum level, Ec refers to the conduction band minimum and Ev is the valence band ... assumption of equal β values is reasonable Namely, the geometry of these three kinds of samples has nearly equal contribution to the electron emission The mechanism of the FE enhancement of the 10 ... to pull the vacuum level down and to lower the electron affinity or emission barrier height of the sample surface On the other hand, the FE enhancement mechanism of the surface hydrogenated sample...

Ngày tải lên: 11/09/2015, 10:18

... fabrication process of FE devices is not taken into account since it is very complicated and not pertinent to the topic of this study However, to achieve the mass production of this kind of emitters, ... fabricated and these emitters may be considered as alternative choices for the present commercial FE devices Moreover, the results and discussion of this study have provided a better understanding of ... electron injection from the Fermi level of the CNTs to the conduction band of metal oxides followed by the electron emission from the conduction band minimum of metal oxides to the vacuum The considerably...

Ngày tải lên: 11/09/2015, 10:18

... Young's modulus of TPa and ultimate strength of 130 GPa [11] In addition to these outstanding properties, the recent developments on graphene synthesis routes and on -2- the understanding of their unique ... cross-link density and hence, on the final properties of the system Thus, we aimed at studying the effect of two types of carbon-based nanofillers, in particular, nanotubes and graphene sheets, ... synthesis and characterization of nanofillers and nanocomposites, participated in the discussion, and drafted the manuscript RV helped in nanocomposite preparation, participated in the discussion, and...

Ngày tải lên: 20/06/2014, 23:20

... synthesis of BN and B–C–N nanotubes One of the great promises of nanoscience and nanotechnology is enabling the continued rapid miniaturization of electronic devices Alternate molecular scale electronics ... distinct diameter and chirality (Fig 1) [1] The latter are called fullerenes having pentagon–hexagon network [2] Actually in the case of fullerenes, many different kinds of fullerenes, from C60 ... (a) Chiral unit cell of the (6,3) nanotube having two atoms and (b) unfolded translational unit cell having 84 atoms with the cell dimension of OP From Ref [37], and Courtesy of Y Akai 39 Quantum...

Ngày tải lên: 04/06/2014, 14:43

... mixing and heating of CNTs and urea to initiate a polymerization reaction of the isocyanic acid and/ or cyanate ion to yield modified CNTs [45] As a summary, there have been a lot of literatures and ... details Institute of Pharmacology and Toxicology and Key Laboratory of Nanopharmacology and Nanotoxicology, Beijing Academy of Medical Science, Zhengzhou, Henan, People’s Republic of China 2Nanotechnology ... halogens, and the reactions often occur only in extreme conditions for the formation of covalent bonds Furthermore, the characterizatiuon of functionalized SWCNTs and the determination of the precise...

Ngày tải lên: 20/06/2014, 22:20

... mechanism of functionalization of SWCNT with benzamide functional group SWCNT diameters of 1.37–2.62 nm It is a strong indication that the framework of SWCNTs was not damaged The ratio of D/G-band ... for covalent attachment of TMPBA onto SWCNTs Conclusions The purification of SWCNTs and the covalent attachment of TMPBA onto the surface of SWCNTs were conducted in a mild and thus less destructive ... as-received ones, and thus the average diameter of the PPA treated SWCNT bundles is approximately four times of that of as-received Fig SEM images: a asreceived SWCNTs (1000009, scale bar is 100...

Ngày tải lên: 22/06/2014, 00:20