Pulmonary tuberculosis is relatively frequent in workers exposed to silica or a mixed dust containing silica (Marchand, 1972). This increased susceptibility has been shown in relation to silica itself (Hunter, i962),coal (Rivers, James, Davies & Thompson, 1957) and talc (Siegal, Smith & Grecnburg, 1943). Since graphite too contains a proportion of silica which is about 2 % in the purest commerc...

Graphite oxide has a complex structure that can be modified in many ways to obtain materials for a wide range of applications. It is known that the graphite precursor has an important role in the synthesis of graphite oxide. In the present study, the basal-plane surface of highly annealed pyrolythic graphite (HAPG) was oxidized by Hummers' method and investigated by Raman spectroscopy and atomi...

This paper describes unusual graphite–sulfide deposits in ultramafic rocks from the Serranı́a de Ronda (Spain) and Beni Bousera (Morocco). These deposits occur as veins, stockworks and irregular masses, ranging in size from some centimeters to a few meters in thickness. The primary mineral assemblage mainly consists of Fe–Ni–Cu sulfides (pyrrhotite, pentlandite, chalcopyrite and cubanite), graph...

Morphologies, petrographic settings and carbon and nitrogen isotopic compositions of graphites in the Acapulco meteorite, the latter determined by secondary ionization mass spectrometry, are reported. Seven different graphite morphologies were recognized, the majority of which occur enclosed exclusively in kamacite. Individual graphite grains also rarely occur in the silicate matrix. Kamacite r...

Aging phenomena in RPCs have been studied since 1996 in the framework of the ATLAS experiment with small-size detectors, irradiated with a Co source. The results evidenced a decrease of the detector rate capability at fixed electric field, due to an increase of the total resistance of electrodes. This was confirmed by an extensive aging test performed on the ATLAS RPC ‘‘module-0’’ at GIF-X5, th...

Microwave (MW) heating has received attention as a new heating source for various industrial processes. Some materials are expected to be a more effective absorber of MW, and graphite is observed as a possible candidate for high-temperature application. We investigated the dependence of the aspect ratio of graphite fibers on both their heating behavior and permittivity under a 2.45 GHz MW elect...

Consolidated bodies of polycrystalline diamond with grain sizes less than 100 nm, nano-polycrystalline diamond (NPD), has been experimentally produced by direct conversion of graphite at high pressure and high temperature. NPD has superior hardness, toughness and wear resistance to single-crystalline diamonds because of its peculiar nano-textures, and has been successfully used for industrial a...

The UK Atomic Energy Authority (UKAEA) is responsible for managing its liabilities for redundant research reactors and other active facilities concerned with the development of the UK nuclear technology programme since 1947. These liabilities include irradiated graphite from a variety of different sources including low irradiation temperature reactor graphite (the Windscale Piles 1 & 2, British...