The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Nano-indentation of glass-like carbons (GCs) heat-treated at different temperatures was carried out with a 3 μm radius spherical tipped indenter. The effect of crystal structure and micro-texture on elastic and elasto-plastic deformation resulting from the indentation was observed. The elastic modulus and yield stress of GCs was found to reduce with elevation of heat treatment temperature (HTT). The...
Silicon carbide/carbon multi-layered coatings have been formed on the surfaces of C/C composites. The multi-layered coatings were deposited by the CVD method at 1200 o C using SiCl 4 , C 3 H 8 and H 2 gases. The principal idea of the present multi-layered coatings is to suppress the through-the-thickness coating cracks by making the thickness of each SiC and...
High-energy ions, such as argon, copper and tungsten ions were implanted in pyrographite and the damages on surfaces, i.e. hillocks and craters, were studied mainly under scanning tunneling microscopy (STM). The number and area of the structural defects increase in function of atomic weight of implanted ions, while ion radius seems not to be a dominant parameter. A change of the inter-atomic distance...
A ζ-potential behavior of close to zero in high pH solutions is observed when carbons and carbides are treated with acetone and ultra-pure water in turn in order to improve the wetting of samples. The abnormal ζ-potential behavior can not be explained by the view of the dissociation of acidic functional groups, but could be accounted for by the effect of H 2 O and atmospheric CO 2 ...
The air blowing reaction has been used to modify the chemical structure and molecular aggregation of pitches for general-purpose carbon fiber on an industrial scale. The purpose in this study is to obtain fundamental ultrasonic data so that one can monitor in situ the change in chemical structure and molecular aggregation state in air blowing reaction. For this purpose, the effects of heat-treatment,...
The surface structure of submicron vapor grown carbon fibers has been investigated by means of scanning tunneling microscopy (STM) at the nanometer and atomic scale. At the nanometer scale the fibers were found to have a relatively smooth topography consisting of more or less rounded platelets just a few nm in diameter. Atomic scale imaging revealed the absence of long range graphitic order. Instead,...
Bamboo-like carbon nanotubes (NTs) were synthesized by a pyrolysis of iron(II) phthalocyanine under Ar/H 2 at 1000 o C. Transmission electron microscopy was used to investigate the bamboo-like nanotubes. The growth mechanism of the bamboo-like NTs is proposed in detail, especially the formation process of compartments of the bamboo-like NTs. The graphite sheath sliding out from the...
Experimental and modeling studies on both surface charge and adsorption of metals on an H-type activated carbon were conducted. The surface charge density decreased with an increase in pH and a decrease in ionic strength. Higher copper adsorption percentage was achieved with higher pH and ionic strength and lower initial concentration. The metal uptake was in the descending order of Cu 2+...
Acrylic textile fibres have been used to prepare activated carbon fibres (ACF). Characterisation by means of elemental analysis, XRD, SEM and low temperature nitrogen adsorption show that the properties of the acrylic ACF compare favourably with those of non-textile PAN, Kevlar and Nomex ACF. A particularly interesting, and never previously reported, feature was observed with fibres activated at 900...
The fractal dimensions D of the pristine and the Li-doped polyacenic semiconductive (PAS) materials have been analyzed by small-angle X-ray scattering (SAXS) and compared with that of graphite. It has become clear that the Li doping generally makes D smaller, which suggests fixation effect of the nanopores on the surface of the material by the doped Li atoms. It is pointed out that the fractal dimension...
Carbon filaments and nanometric carbon particles formed from methane on nano-sized Ni-Cu/Al 2 O 3 catalyst at 720-830 o C were investigated with a transmission electron microscope. Bamboo-shaped carbon filaments were found formed at moderate temperatures. Their morphology depends on the amount of copper doped into the catalyst, the composition of the feed gas and the reaction...
We prepared Sn particles dispersed carbons by pyrolysis of pitch containing various organotin compounds, i.e. tetra-n-butyltin, poly(di-n-butyl(maleate)tin, tetrakis(diethylamino)tin, di-n-butyltin sulfide, poly(di-n-butyltin) and poly(di-n-butyltinoxide), and investigated the characteristics of the carbons and Li ions discharge and charge capacities. The crystallinity of the carbons decreased and...
A 2.5D laminated carbon-carbon composite was studied in the present work. Measurements of density were made by a non-contact and non-destructive method: X-ray tomography. The experimental procedure and artefact correction are described in detail in this paper. The mechanical characterisation was made by tensile, compression, and torsional tests. The role of oxidation on mechanical properties for all...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.