Due to their special properties, nanomaterials had potential application value, and they could play an essential role in improving mudcake quality, assisting in film-forming, reducing lost circulation, and enhancing wellbore stability. Some nanomaterials, such as nanocomposite filtration-reducing agent, nanocomposite viscosifier, nanosized emulsion lubricant, nanometer organoclay, and so on, were introduced, and all of them had significantly influence on the process of drilling operations. As a result, the application of nanomaterials in the field of drilling fluids are very useful for cleaning borehole, maintaining borehole stability, protecting reservoir, and enhancing oil and gas recovery. Finally, the further application of nanomaterials in drilling fluids is also prospected.
Although biosorption for reclaiming single precious metal was frequently reported, the actual subsistent adsorptive competition among different metal ions sometimes shows diverging reinforcement or prohibition for different species. This study tries to screen bacteria that are able to absorb certain precious metals with high selectivity under competitive conditions. The activated sludge was cultivated from enrichment by magnetotactic bacteria medium proposed by Blakemore. Then four microbes, microaerobic bacteria(A) acclimated micro-aerobic bacteria (B), anaerobic bacteria(C) and acclimated anaerobic bacteria(D) were obtained for the following adsorption experiments. The four microbes have high removal efficiency of Au3+ both in its unitary and Au3+-Cu2+binary system. The microaerobic bacteria (B) are good metal catchers and carriers for the uptake of gold in aquatic solution with coexistence of copper. In Pd2+-Cu2+system, there is a collaborative adsorption effect, especially on (B).
Flow field of gas and particles in a conveying vessel is investigated by use of a three-dimensional model combined Eulerian approach. Because of the nozzles’ arrangement in this study, the flow patterns of spouts and bubbles can be seen in the gas-solid flow field, which lead to a non-uniform distribution of gas velocity. Solid volume fraction is high near the bottom and low at the top part. The porosity rises with gas speed increasing, as well as time. An improvement is examined to remove the dead zone at the bottom, which results in particles remaining.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.