Abstract:One-pot syntheses of diethyl carbonate (DEC) from CO 2 , propylene oxide and ethanol were carried out using different solid catalysts. The supercritical CO 2 extraction method was used to separate the liquid products and reactants from the catalysts after reaction. The KNO 3 -CeO 2 and KBr-KNO 3 -CeO 2 were found to be active for the reaction after calcinations. The catalyst was also reusable. The thermodynamic properties of the reaction were also evaluated. The effects of various conditions, such as reaction time, amount of catalysts, molar ratio of the reactants, the composition and calcination temperature of the catalysts on the conversion and yields, were investigated, and the yield of DEC was about 13.0% with a selectivity of 38.5% over KBr-KNO 3 -CeO 2 . The yield of DEC was improved about 10-fold by using KBr-KNO 3 -CeO 2 catalyst compared to CeO 2 .

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The prognostic role of primary tumor location for clinical outcomes of patients with early-stage nodal diffuse large B-cell lymphoma (DLBCL) remains uncertain. We evaluated the relationship between primary tumor site and overall survival (OS) in 9738 early-stage nodal DLBCL patients from the Surveillance, Epidemiology, and End Results (SEER) database. The primary site of the tumors was characterized as supradiaphragm and subdiaphragm according to the definition of lymph node distribution in the Ann Arbor staging. The OS was significantly better for patients of the supradiaphragm group (n = 6038) compared to the ones from the subdiaphragm group (n = 3655) (hazard ratio (HR) 1.24; 95%CI: 1.16–1.33; P < 0.001), and it was preserved after propensity score matching (PSM) (HR 1.15; 95% CI: 1.07–1.24; P < 0.001). Gene enrichment analyses demonstrated that the subdiaphragm group has an upregulated extracellular matrix (ECM)-related signaling, which reportedly can promote growth, invasion, and metastasis of the cancer, and downregulated interferon response, which is considered to have anti-tumor function. Our results indicate the two tumor locations (supradiaphragm and subdiaphragm) presented different prognostic implications for the overall survival, suggesting that the tumor’s location could serve as a prognostic biomarker for early-stage nodal DLBCL patients.

This paper presents a technology that can control fracturing properly in the thin layers in peripheral Daqing oil fields. The layers are thin and numerous, and the lithology is very complex, so the conventional frac or limited entry fracturing has been serious inadaptability. For an example, only 47% of the oil layers produce in a single well, Lots of thin layers in peripheral oil field couldn't be fractured, and reservoir could not be developed fully,, so the effects t of fracturing is poor. Refined-controlled fracturing technique takes into account reservoir nature, lithologic character and the distribution of in-situ stress. In this case, the organic integration of detailed geological research and control technique has been achieved. 308 wells have been applied and tested the technology. The technology break through the limits that the fracturing layers must be more than 4m and stratified according to thickness of the barrier and crustal stress in the past. The effect of perforation parameters to the fracture's initiation direction has been determined by three-dimensional elastic-plastic finite element techniques. Based on the fracture mechanics, the model of fracture extension has been built, and simulated the perforation and its impacts, the contrast of horizontal stress on the deflection of fracture. Based on theoretical study, the perforation design of fracturing wells has been developed.