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Interactions between alkali metals in catalysts and silicon or aluminum minerals in coal are closely related to gasification reactivity, deactivation, and recovery of alkali catalysts during coal catalytic gasification, and alkali-containing minerals and their transformation behaviors are key issues for understanding these interactions. In this paper, Na-containing mineral transformation behaviors and their influences on the catalytic performance during Na 2 CO 3 -catalyzed CO 2 gasification of highalumina coal were comprehensively investigated by thermogravimetry, inductively coupled plasma, X-ray diffraction, and Fourier transform infrared spectroscopy. Moreover, to have a better understanding of the mineral transformation during catalytic gasification, model compounds, i.e., kaolinite (Al 2 O 3 •2SiO 2 •2H 2 O) and boehmite (AlOOH), the main Al-containing minerals in high-alumina coal, were chosen as model compounds to investigate the mineral transformation behaviors. The results show that Na 2 CO 3 first deactivates to generate inert sodium aluminum silicate (Na 1.55 Al 1.55 Si 0.45 O 4 ) at 700 °C, which contributes to the deactivation of catalysts, and then various kinds of sodium aluminum silicates are formed with increasing temperature and Na 2 CO 3 addition. Among them, sodium aluminum silicate [(Na 2 O) 0.33 NaAlSiO 4 ] has been testified as the most stable mineral during gasification. In addition, Na-containing mineral transformation and its resulting products are helpful to the recovery of Al from the ash of catalytic gasification, and 94% recovery rate can be obtained, which is considered to be a method to extract Al from gasification ash. Model kaolinite and boehmite can well explain the mineral transformation during Na 2 CO 3 -catalyzed CO 2 gasification of high-alumina coal.

ObjectiveNeuroendocrine tumors are rare in the ovary. Definitive epidemiologic and prognostic information for neuroendocrine carcinoma of the ovary is lacking. This retrospective population-based study aimed to elucidate the demographic and clinicopathologic characteristics of neuroendocrine carcinoma of the ovary.MethodsPatients with neuroendocrine carcinoma of the ovary diagnosed between January 1994 and December 2014were identified from the Surveillance, Epidemiology, and End Results (SEER) database of the National Cancer Institute. Cancer-specific survival was calculated by Kaplan-Meier plots and comparisons were performed using the log-rank test. A Cox hazard regression analysis was performed to identify independent predictors of cancer-specific survival in patients with neuroendocrine carcinoma of the ovary.ResultsA total of 166 patients were included, and 21.1% were younger than 50 years old. The majority of patients (59.6%) presented with unilateral tumors. Patients with neuroendocrine carcinoma of the ovary had significantly worse survival compared with most subtypes of epithelial ovarian cancer (including serous, endometrioid, mucinous, and clear cell), and similar to ovarian carcinosarcoma. The rate of cancer-specific survival was significantly different under the SEER histologic stages. Patients with low-grade neuroendocrine carcinoma of the ovary had longer average survival times than those with high-grade neuroendocrine carcinoma of the ovary (HR 3.43, 95% CI 1.56 to 7.54, p=0.002). Patients with neuroendocrine carcinoma of the ovary who underwent surgery had significantly better survival than those who did not undergo surgery (HR 2.23; 95% CI 1.45 to 3.43, p=<0.05).ConclusionsEarly clinical stage and low tumor grade independently predict better survival in patients with neuroendocrine carcinoma of the ovary. Surgery may be a useful therapy for neuroendocrine carcinoma of the ovary.

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