Propylene/propane (C 3 H 6 /C 3 H 8 ) separation is a momentous and challenging process for the production of polymer-grade C 3 H 6 with high energy penalty. Here, we report the separation of C 3 H 6 and C 3 H 8 with two isostructural anionpillared metal−organic frameworks [GeFSIX-2-Cu-i (also termed as ZU-32) and SIFSIX-2-Cu-i]. Interestingly, GeFSIX-2-Cu-i shows a high uptake ratio of C 3 H 6 /C 3 H 8 (1.49 at 298 K and 1.0 bar), outperforming most of the existing materials, such as MOF-74 series (1.16−1.31), MAF-23-O (1.17), and CuBTC (1.12). Furthermore, the breakthrough experiments for C 3 H 6 /C 3 H 8 (50/50, v/v) binary mixtures were performed on GeFSIX-2-Cu-i and SIFSIX-2-Cu-i, respectively. Under dynamic conditions, both GeFSIX-2-Cu-i and SIFSIX-2-Cu-i present excellent separation performance, especially for GeFSIX-2-Cu-i with a C 3 H 6 capacity of 2.2 mmol g −1 (calculated from breakthrough curves). The binding sites of GeFSIX-2-Cu-i for C 3 H 6 and C 3 H 8 were investigated by the first-principles density functional theory calculations, and the results reveal that the strong hydrogen-bonding interactions between GeF 6 2− anions and C 3 H 6 as well as π−π interactions between organic linkers and C 3 H 6 lead to high C 3 H 6 uptake on GeFSIX-2-Cu-i. This work indicates that the anion-pillared metal organic frameworks, with high hydrothermal stability, can be considered as candidates for the separation of C 3 H 6 /C 3 H 8 mixtures.

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To assess the impact of the number of resected lymph nodes (RLNs) for survival in esophageal cancer (EC) patients treated with preoperative radiotherapy and cancer-directed surgery. The Surveillance Epidemiology and End Results (SEER) database was queried to identify EC patients treated from 1988 to 2012 who had complete data on the number of positive lymph nodes and number of RLNs. Kaplan–Meier survival analysis and Cox regression proportional hazard methods were used to determine factors that significantly impact cause-specific survival (CSS) and overall survival (OS). There were a total of 3,159 patients who received preoperative radiotherapy and cancer-directed surgery. The median number of RLNs was 10 in both patients who received and did not receive preoperative radiotherapy (P = 0.332). Cox regression univariate and multivariate analysis showed that RLN count was a significant prognostic factor for CSS and OS. Patients with 11–71 RLNs had better CSS (hazard ratio [HR] = 0.694, 95% confidence interval [CI]: 0.603–0.799, P < 0.001) and OS (HR = 0.724, 95% CI: 0.636–0.824, P < 0.001) than patients with 1–10 RLNs. The 5-year CSS rates were 39.1% and 44.8% in patients with 1–10 RLNs and 11–71 RLNs, respectively (P < 0.001). The 5-year OS rates were 33.7% and 39.9% in patients with 1–10 RLNs and 11–71 RLNs, respectively (P < 0.001). A higher number of RLNs was associated with better survival by tumor stage and nodal stage (all P < 0.05). RLN count is an independent prognostic factor in EC patients who undergo preoperative radiotherapy and cancer-directed surgery.

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