Showing papers in "Carbon in 1971"

TL;DR: In this paper, a study was made of the graphitization of monolithic glass-like carbon as catalyzed by molten metals and it was concluded that elements such as Ni, Co, Fe, Pt, Mo, Cr, and B are highly effective in catalyzing graphitisation.

TL;DR: In this paper, the specific adsorption of p-nitrophenol on carbon, thought to be an electron donor-acceptor complex, is shown to be strongly dependent on the state of surface oxidation.

TL;DR: In this paper, small volume tests have been conducted using the elastica method to determine the strength of the material between flaws, and the results indicated that this strength would be in the neighbourhood of 106 psi in the absence of gross flaws.

TL;DR: The nature of the basic surface oxides on carbon was studied by chemical reactions, e.g. methylation with methanol/sulphuric acid.

TL;DR: In this article, a new phenomenon was observed, namely the formation of a spherulitic (botryoidal) carbon, about μ-sized, which although intrinsically anisotropic can confer isotropic properties to the bulk graphite.

TL;DR: In this paper, the catalytic action of iron powder added in small concentration to a powdered sample of hard carbon was studied by means of electron microscopy (bright and dark field), electron diffraction (SAD), optical microscopy and scanning microscopy.

TL;DR: The d-spacing distribution in a number of carbon blacks was accurately measured by means of an internal calibration standard as discussed by the authors, and the distribution appears to be random, following a log-normal pattern for all blacks, except for thermal blacks, which are concentrically arranged around the particle nucleus.

TL;DR: In this article, the early electronic energy band model of carbon and its later modifications such as faster collapse of energy gap and the presence of band overlap in graphites are recalled to introduce the main topic of the paper.

TL;DR: The carbon-sulphur complex, resulting from fixation of sulphur on charcoal, is highly stable and can evolve largely hydrogen sulphide and carbon disulphide but the entire amount cannot be recovered even at 1200°C.

TL;DR: In this paper, an electrochemical technique has been used to obtain thermodynamic information on graphite-bisulfate lamellar compounds and free energies, enthalpies and entropies of formation of the compounds were determined.

TL;DR: In this article, the isotherm of bromine on pyrolytic graphite was studied at 20°C by stepwise bromination, and several phases of graphite bromide were identified, which have compositions of C 8 Br, C 12 Br,C 16 Br and C 20 Br.

TL;DR: In this paper, the effect of iron and nickel impurities on the development of microporosity during the gasification of 850°C polyfurfuryl alcohol carbon with carbon dioxide has been investigated.

TL;DR: In this paper, the role of closed pores is emphasised and a model of the activation process is developed which enables the closed pore volume of carbon to be determined without assuming a value for the density of the carbon in the pore walls.

TL;DR: In this article, the topographical changes resulting from the attack of gaseous hydrogen, oxygen and nitrogen on the basal plane surfaces of natural graphite crystals have been studied optically.

TL;DR: In this paper, reflected polarized light micrography using crossed polarizers with a gypsum plate has been employed to investigate the microstructure of carbonaceous mesophase formed at the early stage carbonization of pitches.

TL;DR: In this article, high-dimensional graphite has been irradiated to doses of 2.5 × 1022 n.v.t. at temperatures between 250°C and 470°C.

TL;DR: For isotropic carbons with constant density, the Young's modulus and fracture stress increase with decreasing crystallite size possibly due to cross-linking either between crystallites or between layer planes as discussed by the authors.

TL;DR: In this article, the authors studied the chemisorption of hydrogen on activated Graphon over the range 80-600°C at a hydrogen pressure of 0.10 Torr and at 500°C over the pressure range 0.020-0.47 Torr.

TL;DR: In this paper, it was shown that the number of unpaired electrons formed during the powdering process is quite small and the observed effects might be accounted for if ball-milling introduces new dislocations into the solid or causes damage to those already present.

TL;DR: A shape-selective carbon molecular sieve support-platinum catalyst system has been prepared by carbonizing polyfurfuryl alcohol (PFA) containing small amounts of chloroplatinic acid.

TL;DR: In this paper, the authors used mass-spectrometers to identify those molecular species which condense to form semi-coke by hydrogenolysis using atomic and molecular hydrogen.

TL;DR: In this article, the authors measured volume changes produced in Saran charcoal by the adsorption of water, methanol and benzene vapours, and found that the water uptake was about 75% of the saturation value.

TL;DR: In this paper, active hydrogen on carbon surfaces covered with basic surface oxides in the hydroxide form was measured by deuterium exchange with D 2 O using a gravimetric technique.

TL;DR: In this paper, two hard carbons, PH-7 and PH-15, were heat-treated at various temperatures under pressure of 5 kbar and examined using a polarized light microscope.

TL;DR: In this paper, a number of anisotropic and near-isotropic graphites were irradiated at 300° to 1500°C to fluences of up to 1.5 × 10 22 n/cm 2 (E > 0.18 MeV).

TL;DR: In this paper, the growth of filaments has been observed to occur on a carbon substrate, and it has been shown that they are graphitic and of three different types: tubular, twisted, irregular, and balloon-like.

TL;DR: The microstructure of carbon and graphite fibers made from a rayon precursor has been studied by both transmission and surface replica electron microscopy as mentioned in this paper, and it has been shown that failure of the bonds between these fibrils is responsible for the grainy appearance of fracture surfaces and for the tendency of the fibers to split longitudinally.

TL;DR: In this article, an 850°C polyfurfuryl alcohol carbon has been gasified at 800°C in pure carbon dioxide and mixtures thereof with carbon monoxide to 25 per cent burnoff.

TL;DR: In this article, an attempt is made to relate the unusual irradiation behavior of Poco graphite to its microstructure, showing that the graphites behave isotropically under irradiation and show improved dimensional stability over conventional nuclear graphites.

TL;DR: In this article, it was shown that the internal pore structure of graphite can be permanently damaged by mercury at high pressure and that the effect of the damage for the particular material studied was to increase the amount of accessible pores of size smaller than 2 μm.