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

Materials Challenges in Nuclear Energy

Scanning electrochemical microscopy (SECM) is an electroanalytical scanning probe technique capable of imaging substrate topography and local reactivity with high resolution. Since its inception in 1989, it has expanded into a wide variety of research areas including biology, corrosion, energy, kinetics, instrumental development, and surface modification. In the past 25 years, over 1800 peer-reviewed publications have focused on SECM, including several topical reviews. However, these reviews often omit key details, forcing readers to search the literature. In this review, we provide a comprehensive summary of the experimental parameters (e.g., solvents, probes, and mediators) used in all SECM publications since 1989, irrespective of the application. It can be used to rapidly assess experimental possibilities and make an informed decision about experimental design. In other words, it is a practical guide to SECM.

Scanning Electrochemical Microscopy: A Comprehensive Review of Experimental Parameters from 1989 to 2015.

Electrochemical, surface and quantum chemical studies of novel imidazole derivatives as corrosion inhibitors for J55 steel in sweet corrosive environment

Corrosion of a stainless steel and nickel-based alloys in high temperature supercritical carbon dioxide environment

Under CO2 exposure at an intermediate temperature, typically 550 °C, 9Cr–1Mo steel forms a duplex oxide scale made of an outer magnetite layer and an almost-as-thick inner Fe–Cr rich spinel oxide layer It is proposed that the inner Fe–Cr spinel layer grows according to a mechanism involving void formation at the oxide/metal interface The driving force for pore formation is the outward magnetite growth: iron vacancies are injected at the oxide/metal interface then condense into voids The fresh metallic surface made available is then oxidized by CO2, which diffuses fast through the scale The physical aspects, the integrity and the nature of the scale are shown to be very dependent on the oxygen potential existing in the environment

Corrosion of 9Cr steel in CO 2 at intermediate temperature I: Mechanism of void-induced duplex oxide formation

In parallel to the formation of a duplex oxide scale, 9Cr–1Mo steel carburizes strongly under CO2 at 550 °C and this carburization accelerates with time. It is observed that an increase of the total CO2 pressure in the environment from 1 to 250 bars induces a higher carbon deposition in the inner Fe–Cr rich spinel oxide layer. In order to explain this phenomenon, modelling of the carburization process was carried out. A mechanism involving gas diffusion of CO2 and CO through the oxide layer, the Boudouard reaction and carbon diffusion through the metallic substrate is proposed.

Corrosion of 9Cr Steel in CO2 at Intermediate Temperature II: Mechanism of Carburization

Corrosion of high temperature metallic materials in VHTR

High temperature reactivity of two chromium-containing alloys in impure helium

9Cr–1Mo steel forms in CO2 at 550 °C a duplex oxide layer containing an outer magnetite scale and an inner Fe–Cr rich spinel scale. The inner spinel oxide layer is formed according to a void-induced oxidation mechanism. The kinetics of the total oxide growth is simulated from the proposed oxidation model. It is found that the rate limiting step of the total oxide growth is iron diffusion through high diffusion paths such as oxide grain boundaries in the inner Fe–Cr rich spinel oxide layer. In the proposed oxidation model, a network of nanometric high diffusion paths through the oxide layer allows the very fast supply of CO2 inside pores formed at the oxide/metal interface. Its existence is demonstrated to be physically realistic and allows explaining several observed physical features evolving in the oxide layer with time.

Fabien Rouillard

Papers

Corrosion of 9Cr steel in CO 2 at intermediate temperature I: Mechanism of void-induced duplex oxide formation

Corrosion of 9Cr Steel in CO2 at Intermediate Temperature II: Mechanism of Carburization

Corrosion of high temperature metallic materials in VHTR

High temperature reactivity of two chromium-containing alloys in impure helium

Corrosion of 9Cr Steel in CO 2 at Intermediate Temperature III: Modelling and Simulation of Void-induced Duplex Oxide Growth