Seismic modelling and ava analysis of hidrocarbon traps

In this study, forward seismic modelling of four geological models with Hydrocarbon (HC) traps were performed by ray tracing method to produce synthetic seismogram of each model. The idea is to identify the Hydrocarbon Indicators (HCI‟s) such as bright spot, flat spot, dim spot and Bottom Simulating Reflector (BSR) in the synthethic seismogram. The modelling was performed in DISCO/FOCUS 5.0 seismic data processing programme. Strong positive and negative reflection amplitudes and some artifact reflection horizons were observed on produced seismograms due to rapid changes in subsurface velocity and geometry respectively Additionally, Amplitude-versus-angle (AVA) curves of each HCIs was calculated by the Crewes Zoeppritz Explorer programme. AVA curves show that how the reflection coefficients change with the density and the P and S wave velocities of each layer such as oil, gas, gas hydrate or water saturated sediments. Due to AVA curves, an increase in reflection amplitude with incident angle of seismic waves corresponds to an indicator of a hydrocarbon reservoir

Mapping of mechanical properties of cement paste microstructures

The presented study is related to the EU 7 th Framework Programme CODICE (COmputationally Driven design of Innovative CEment-based materials). The main aim of the project is the development of a multi-scale model for the computer based simulation of mechanical and durability performance of cementitious materials. This paper reports results of micro/nano scale characterisation and mechanical property mapping of cementitious skeletons formed by the cement hydration at different ages. Using the statistical nanoindentation and micro-mechanical property mapping technique, intrinsic properties of different hydrate phases, and also the possible interaction (or overlapping) of different phases (e.g. calcium-silcate-hydrates) has been studied. Results of the mapping and statistical indentation testing appear to suggest the possible existence of more hydrate phases than the commonly reported LD and HD C-S-H and CH phases

Use of a New Tetrazolium-Based Assay to Study the Production of Superoxide Radicals by Tobacco Cell Cultures Challenged with Avirulent Zoospores of Phytophthora parasitica var nicotianae1

The relationship between the production of reactive oxygen species and the hypersensitive response (HR) of tobacco (Nicotiana tabacum L.) toward an incompatible race of the Oomycete Phytophthora parasitica var nicotianae has been investigated. A new assay for superoxide radical (O2−) production based on reduction of the tetrazolium dye sodium,3′-(1-[phenylamino-carbonyl]-3,4-tetrazolium)-bis(4-methoxy-6-nitro) benzene-sulfonic acid hydrate (XTT) has enabled the quantitative estimation of perhydroxyl/superoxide radical acid-base pair (HO2·/O2−) production during the resistant response. Tobacco suspension cells were inoculated with zoospores from compatible or incompatible races of the pathogen. Subsequent HO2·/O2− production was monitored by following the formation of XTT formazan. In the incompatible interaction only, HO2·/O2− was produced in a minor burst between 0 and 2 h and then in a major burst between 8 and 10 h postinoculation. During this second burst, rates of XTT reduction equivalent to a radical flux of 9.9 × 10−15 mol min−1 cell−1 were observed. The HO2·/O2− scavengers O2− dismutase and Mn(III)desferal each inhibited dye reduction. An HR was observed in challenged, resistant cells immediately following the second burst of radical production. Both scavengers inhibited the HR when added prior to the occurrence of either radical burst, indicating that O2− production is a necessary precursor to the HR.