Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

Mechanical properties of nanocrystalline materials

http://www.uniroma2.it/didattica/tbs2/deposito/Manufacture,_characterisation_and_application_of_cellular_metals_and_metal_foams.pdf

Manufacture, characterisation and application of cellular metals and metal foams

There have been a number of review papers on layered silicate and carbon nanotube reinforced polymer nanocomposites, in which the fillers have high aspect ratios. Particulate–polymer nanocomposites containing fillers with small aspect ratios are also an important class of polymer composites. However, they have been apparently overlooked. Thus, in this paper, detailed discussions on the effects of particle size, particle/matrix interface adhesion and particle loading on the stiffness, strength and toughness of such particulate–polymer composites are reviewed. To develop high performance particulate composites, it is necessary to have some basic understanding of the stiffening, strengthening and toughening mechanisms of these composites. A critical evaluation of published experimental results in comparison with theoretical models is given.

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Effects of particle size, particle/matrix interface adhesion and particle loading on mechanical properties of particulate–polymer composites

Below 1000°C the oxidation of nickel cannot be controlled by the diffusion of ions through the bulk crystal lattice of the pure oxide, because the measured oxidation rates are several orders of magnitude faster than would be predicted on this basis. Short-circuit diffusion through oxide grain boundaries or dislocations has usually been held responsible, but there has hitherto been no proper quantitative confirmation of this mechanism. We report measurements of the oxide scale thickness and oxide grain size as a function of time during the oxidation of high-purity nickel in the temperature range 500–800°C. All the oxidation experiments were carried out in pure oxygen at a pressure of one atmosphere. The measured parabolic oxidation rate constants have been compared with those calculated from grain boundary diffusion data obtained in our previous work, using a grain boundary diffusion model for the oxidation process. The quantitative agreement between measured and calculated oxidation rates shows c...

A quantitative demonstration of the grain boundary diffusion mechanism for the oxidation of metals

In the past two decades much interest has been aroused in ultrafine scale structures such as nanocrystalline materials. It is however also of value to examine the mechanical behavior of materials as the size of the basic microstructural unit, whether the grain size or the interphase spacing, is progressively reduced to the scale of 1 µm or lower.

The Mechanical Properties of Fine Scale Metallic Materials

The stability of microstructure in the iron-carbon system during cyclic deformation

Electrodeposition of composite iron oxide-polyelectrolyte films

Metallography of adhesive wear in aluminum alloys

Composite films consisting of Fe hydroxide, Ni hydroxide and polyethylenimine (PEI) were obtained by the combined electrolytic-electrophoretic deposition method. The proposed method for PEI charging and deposition is based on the use of cationic polymer-metal ion complexes. Cathodic deposits were obtained on Pt and Ag substrates. By varying both the concentration of PEI in solutions and the deposition time, the amount of material deposited and its composition can be varied. The method was used to fabricate NiFe2O4 films. The deposits were studied by thermogravimetric analysis, X-ray diffraction analysis and SEM. The mechanism of electrochemical intercalation of PEI into hydroxide deposits is discussed.

J.D. Embury

Papers

The Mechanical Properties of Fine Scale Metallic Materials

The stability of microstructure in the iron-carbon system during cyclic deformation

Electrodeposition of composite iron oxide-polyelectrolyte films

Metallography of adhesive wear in aluminum alloys

Electrochemical Preparation of Ni and Fe Hydroxide/Oxide Films Using Polyethylenimine