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A case of extramedullary plasmacytoma of the nasal cavity was reported and its mainly clinical manifestations were nasal obstruction, running nose and olfactory degeneration. Nasal endoscopy and paranasal sinus CT indicated tract tumor in left nasal (the nature to be investigated), the pathological result after surgical resection of the tumor suggests extramedullaryplasmacytoma (left nasal cavity).Clinical diagnosis was extramedullaryplasmacytoma (left nasal cavity), chronic sinusitis (left). Radiotherapy was continued after discharge and the follow-up was satisfactory.
RESUMO
This study examines the cotransport of graphene oxide (GO) and Cu in porous media. The impacts of GO concentration and ion strength (IS) on Cu transport in laboratory packed columns were investigated. The results indicated that GO had fairly high mobility at a IS of 1mM, and could serve as an effective carrier of Cu(II). The facilitated transport was found to increase with increasing concentration of GO (CGO). The peak effluent concentration (C/C0)max of Cu was 0.57 at CGO of 120mg/L and IS=1mM and 0.13 at 40mg/L and IS=1mM. The Cu appears to be irreversibly adsorbed by the sand because no Cu appeared in the effluent in the absence of GO. However, the GO-facilitated Cu transport was reduced as the IS increased from 1 to 1000mM. In fact, the facilitated transport was zero percent at an IS of 1000mM. Particle size analysis, Zeta potential measurements and DLVO calculations demonstrated that higher IS values made the GO became unstable and it flocculated and attached to the sand. We also fed GO into the column pre-equilibrated by Cu as sequential elution experiments and found that the later introduced GO can complex the pre-adsorbed Cu from the sand surface because GO has a higher adsorption affinity for Cu. An advection-dispersion-retention numerical model was able to describe the Cu and GO transport in the column. Our work provides useful insights into fate, transport and risk assessment of heavy metal contaminants in the presence of engineered nanoparticles.
RESUMO
The influence of cation composition in mixed Na-Ca electrolyte systems on the transport of graphene oxide particles in saturated porous media was studied. Column experiments were conducted to elucidate the transport behavior of GO by varied molar ratios of Ca2+/Na+ but of constant ionic strength (IS). The results show that retention of GO in sand column is strongly dependent on IS in the presence of Ca2+, featuring serious deposition rates (Rd) at the higher IS of 10 mM. The maximum Rd was 48.22% at 1 mM and 98.53% at 10 mM. However, there was no obvious difference in GO retention in solutions that only contained Na+ when the IS increased from 1 to 10 mM, and the Rd was 35.17% and 38.21% respectively. The molar ratio of Ca2+/Na+ in solution was much more influential in altering the particle retention behavior at the higher IS of 10 mM, compared with little influence at 1 mM. It was supposed that compression of diffuse double layers mainly controlled GO deposition under lower IS, while charge neutrality and metal (Ca2+) bridging played a significant role at the higher IS. A numerical advection-dispersion-retention model considering the combined processes of Langmuirian dynamics blocking and depth-dependent straining was successfully developed to simulate the transport process of GO through the sand column. Derjaguin-Landau-Verwey-Overbeek (DLVO) interaction energy calculations were also performed to better understand the mechanisms of GO mobility. Coupling analysis of breakthrough experiments, DLVO theory and numerical modeling in this work provides insight into the mechanisms of GO transport in saturated porous media and is useful for reliable prediction of nanoparticle penetration through the vadose zone.