The Removal of Strontium Ions from an Aqueous Solution Using Na-A Zeolites Synthesized from Kaolin.

Sr ions in an aqueous solution were removed using Na-A zeolites synthesized from kaolin, a natural mineral. Na-A zeolites with high crystallinity were synthesized using NaOH/kaolin mass ratios of 0.6 (ZK06) and 0.

Characterizing land use effect on shallow groundwater contamination by using self-organizing map and buffer zone.

Nitrate-nitrogen (NO-N) contamination in groundwater is a major problem of drinking and domestic waters in rural areas. This study revealed the influence of land use type on shallow alluvial groundwaters in a typical rural area in South Korea by applying a self-organizing map (SOM), principal component analysis (PCA), and hierarchical cluster analysis (HCA). The uncertainty of spatial information on land use was improved by using a buffer zone of the average influence radius of 32.

Contribution of nitrate-nitrogen concentration in groundwater to stream water in an agricultural head watershed.

This study characterized nitrate-nitrogen (NO-N) concentrations in groundwater and stream water in an agricultural head watershed in South Korea and identified the pollution load of NO-N as a result of the groundwater entering streams using field surveys, analyses of chemical constituents, and numerical modeling. The mean NO-N concentration in groundwater was 7.373 mg/L, which is approximately 1.

Incidence and predictors of HBV relapse after cessation of nucleoside analogues in HBeAg-negative patients with HBsAg ≤ 200 IU/mL.

The predictors of hepatitis B virus (HBV) relapse and HBsAg loss after cessation of nucleos(t)ide analogues (NA) in HBeAg-negative patients with end-of-treatment HBsAg ≤ 200 IU/mL remains unclear. The study recruited 119 chronic hepatitis B (CHB) patients who achieved end-of-treatment HBsAg ≤ 200 IU/mL, were treated with lamivudine (n = 34) and entecavir (n = 85). The 5-year rates of post-treatment virological relapse, clinical relapse, and HBsAg loss at 60 months were 39.