Magnetic Field Distance Research Articles

Recovery of heavy medium in coal washing plant using a flat plate magnetic separator and optimization of flow and magnetic fields

Heavy medium coal washing technique can achieve deep coal desulfurization and ash reduction. It is an important approach that can ensure clean and efficient utilization of coal. Heavy medium coal washing technique is affected by the efficient and high-quality recovery of heavy medium. While, it has the poor recovery due to the finer particle size and weaker magnetic property using the drum magnetic separator. In this study, the recovery of heavy medium was performed using a flat magnetic separator based on a plane extrusion magnetic system. The effect flow field and magnetic field on the recovery of the heavy medium were theoretically discussed, and the mechanism was clarified. The main results demonstrated that the plane extrusion magnetic system had a high magnetic field strength with B > 0.5 T, and the magnetic field distance was greater than 30 mm with B > 0.2 T. Additionally, the leakage of magnetic field lines was less regardless of the position of the magnetic poles. The magnetic system was suitable for plate installation. A fluid domain height changes from 40 cm to 60 cm during the recovery cycle had a significant effect on the magnetic field strength, and an increase in the fluid domain height extended the motion trajectory of the magnetic particles. A flow velocity changes from 1.2 m/s to 2.0 m/s directly affected the competitive forces intensity. However, the competitive intensity was significantly less than that of the magnetic force, and an increase in the flow field velocity slightly affected the motion trajectory of magnetic particles. The effect of the magnetic particle concentration on the motion trajectory of magnetic particles was unclear due to the stable magnetic properties of the heavy medium. The theoretical and experimental analysis confirmed that the thin flow field film separation space of the flat plate magnetic separator and the magnetic field characteristic of the plane extrusion magnetic system, could be beneficial to the separation of finer particle size and weaking magnetic susceptibility. Additionally, the counterbalance relationship between the magnetic and competitive forces fulfilled the requirements of the high-efficiency magnetic separation of the heavy medium.

OPEN CLUSTERS AS PROBES OF THE GALACTIC MAGNETIC FIELD. I. CLUSTER PROPERTIES

Stars in open clusters are powerful probes of the intervening Galactic magnetic field, via background starlight polarimetry, because they provide constraints on the magnetic field distances. We use 2MASS photometric data for a sample of 31 clusters in the outer Galaxy, for which near-IR polarimetric data were obtained, to determine the cluster distances, ages, and reddenings via fitting theoretical isochrones to cluster color-magnitude diagrams. The fitting approach uses an objective chi^2 minimization technique to derive the cluster properties and their uncertainties. We found the ages, distances, and reddenings for 24 of the clusters, and the distances and reddenings for six additional clusters that were either sparse or faint in the near-IR. The derived ranges of log(age), distance, and E(B-V) were 7.25-9.63, ~670-6160 pc, and 0.02-1.46 mag, respectively. The distance uncertainties ranged from ~8 to 20%. The derived parameters were compared to previous studies, and most cluster parameters agree within our uncertainties. To test the accuracy of the fitting technique, synthetic clusters with 50, 100, or 200 cluster members and a wide range of ages were fit. These tests recovered the input parameters within their uncertainties for more than 90% of the individual synthetic cluster parameters. These results indicate that the fitting technique likely provides reliable estimates of cluster properties. The distances derived will be used in an upcoming study of the Galactic magnetic field in the outer Galaxy.

Targeting Magnetic Nanoparticles in High Magnetic Fields for Drug Delivery Purposes

AbstractBiodegradable magnetic nanoparticles were synthesized using Poly(L-Lactic Acid) and magnetite nanoparticles (∼14 nm) at different dosages, and then these nanaoparticles (nanocomposites) and pure magnetic particles were targeted in external magnetic fields by changing the test parameters. The magnetic field test results showed that magnetic saturation, fluid speed, magnetic field distance and particle size were extremely effective for a magnetic guidance system that is needed for an effective drug delivery approach. Thus, it is assumed that such nanoparticles can carry drugs (chemotherapy) to be able to cure cancer tumors as well as many other diseases.