Shiwen Yao

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A series of pulse sequences is described which selectively excite signals only from flowing spins. The method is based on the binomial selective excitation sequences employed for solvent suppression in NMR spectroscopy, combined with 180 degrees refocusing of chemical shift and static field inhomogeneity effects and the application of bipolar gradients to(More)
Quantitative flow and diffusion measurements have been made for water in model porous media, using magnetic resonance micro-imaging methods. The samples consisted of compacted glass beads of various sizes down to 1 mm diameter. Typical flow and diffusion images exhibited a spatial resolution of 117 microns x 117 microns and velocities in the range 1-2 mm/s.(More)
A chemical shift selective NMR flow imaging sequence using stimulated echoes for data acquisition is presented. The sequence was tested using a 20% (vol/vol) oil-water emulsion formed from a soluble cutting oil, which was passed through a simple flow phantom to yield two-dimensional velocity distribution maps of the oil droplets and of the water separately.(More)
In this work, we recover cobalt from waste 18650-type lithium-ion batteries by acid leaching. The cathode material is completely dissolved, after leaching waste batteries by using 10 mol/L industrial sulfuric acid at 70 ̊C for 1 h. The rate of cobalt leaching is nearly 100%. Removal of sodium carbonate, iron, aluminum and other impurities from the leaching(More)
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