The porous microstructure of hydrates governs the mechanical strength of the hydrate-bearing sediment. To investigate the growth law and microstructure of hydrates in porous media, the growth process of tetrahydrofuran (THF) hydrate under different concentration of THF solution is directly observed using Magnetic Resonance Imaging (MRI). The images show that the THF hydrate grows as different m...

In this work, five different thermodynamic models for correlating the fugacity of water and Tetrahydrofuran (THF) in liquid phase in equilibrium with hydrogen hydrate phase, based on the van der Waals–Platteeuw (vdW-P) statistical thermodynamic model are used and the equilibrium pressures of hydrogen hydrate at different temperatures are calculated. The dissociation pressure of binary hydrogen ...

The production of natural gas from sub-seafloor gas hydrates is one possible strategy to meet the world’s growing demand for energy. On the other hand, climate warming scenarios call for the substitution of fossil energy resources by sustainable energy concepts. Burning natural gas from gas hydrates could be emission neutral if it was combined with a safe storage of the emitted CO2. Laboratory ...

Metal hydrazine, pyridine–2-carboxylate hydrates, pyridine–3-carboxylate hydrates, [ML(N2H4)0.5.H2O] where L = pyridine–2-carboxylic acid, pyridine–3-carboxylic acid and M = Co, Ni, Mn and Zn have been prepared and characterized by analytical, IR, UV-Vis and XRD Studies. Thermal decomposition of the compounds is studied from room temperature to 1200C by TG-DTA analysis. The compounds were found...

The unique nature of the molecular structures of gas hydrates results in curious acoustic properties which have yet to be adequately characterized. Understanding the acoustic behavior of hydrates in liquids, in bubbly liquids, and in sediments containing liquids and/or gas is vital for surveying their location using seismic or echosounding techniques and may become a key tool for monitoring hyd...

In this work we investigated the behavior of methane hydrates dispersed in crude oils from different fields at temperatures below 0°C. In case of crude oil emulsion the size of water droplets is in the range of 50÷100μm. The size of hydrate particles formed from droplets is the same. The self-preservation is not expected in this field. However, the self-preservation of hydrates with the size of...

Gas hydrates are crystalline ice-like solid materials enclosing gas molecules inside. The possibility of the presence of gas hydrates with amino acids in the universe is of interest when revealing the potential existence of life as they are evidence of a source of water and organic precursors, respectively. However, little is known about how they can naturally coexist, and their crystallization...

The kinetics of film growth of hydrates of methane, ethane, and methane-ethane mixtures were studied by exposing a single gas bubble to water. The morphologies, lateral growth rates, and thicknesses of the hydrate films were measured for various gas compositions and degrees of subcooling. A variety of hydrate film textures was revealed. The kinetics of two-dimensional film growth was inferred f...

Gas hydrates stored on continental shelves are susceptible to dissociation triggered by environmental changes. Knowledge of the timescales of gas hydrate dissociation and subsequent methane release are critical in understanding the impact of marine gas hydrates on the ocean-atmosphere system. Here we report a methane efflux chronology from five sites, at depths of 220-400 m, in the southwest Ba...

Gels of calcium-silicate-hydrates (C-S-H) are the glue that is largely responsible for the mechanical properties of cement. Despite their practical relevance, their nano-scale structure and mechanics are still mainly unexplored, because of the difficulties in characterizing them in a complex material like cement. We propose a colloidal model to investigate the gel mechanics emerging in the crit...