Recently,an emerging category green of energetic material ammonium dinitramide(ADN)has exhibited promising application in propellants due to its outstanding merits in energy release and environmental friendliness.It c...Recently,an emerging category green of energetic material ammonium dinitramide(ADN)has exhibited promising application in propellants due to its outstanding merits in energy release and environmental friendliness.It can be considered to substitute traditional oxidizer of ammonium perchlorate(AP)in military systems and aerospace.In this paper,a novel spherical energetic composite ADN/copper alginate(CA)with a microporous structure was designed and prepared by the W/O gel emulsion method,and a desirable porous microsphere structure was obtained.Multiple characterization techniques were used to investigate the structure and properties of ADN/CA composites.The results showed that ADN crystals were homogeneously encapsulated in an alginate-gel matrix.Thermal decomposition temperature was reduced to 151.7℃compared to ADN,while the activation energy of them was reduced from 129.73 k J/mol(ADN)to 107.50 k J/mol(ADN/CA-4).In addition,as-prepared samples had lower impact and frictional sensitivity than ADN.The mechanism of sensitivity reduction and decomposition are also discussed.Constant-volume combustion tests show that peak pressure of the ADN/CA-4 achieves 253.4 k Pa and pressurization rate of 2750.4 k Pa/s.Hence,this has a promising application in improving the combustion performance and safety performance of solid propellants.展开更多
Background:Epithelial-mesenchymal transition(EMT) is believed to be the critical process in malignant tumor invasion and metastases,and has a great influence on improving the survival rate in non-small-cell lung cance...Background:Epithelial-mesenchymal transition(EMT) is believed to be the critical process in malignant tumor invasion and metastases,and has a great influence on improving the survival rate in non-small-cell lung cancer(NSCLC) patients.Recent studies suggested that eukaryotic initiation factor 5A-2(eIF5A-2) might serve as an adverse prognostic marker of survival.We detected eIF5A-2 in NSCLC A549 cells,and found that the invasive capability correlates with the eIF5A-2 expression.Methods:Transforming growth factor(TGF)-β1 was used to induce EMT in A549 cells.Western blotting,immunofluorescence,wound healing assay,and transwell-matrigel invasion chambers were used to identify phenotype changes.Western blotting was also used to observe changes of the expression of eIF5A-2.We down-regulated the eIF5A-2 expression using an eIF5A-2 siRNA and identified the phenotype changes by western blotting and immunofluorescence.We tested the change of migration and invasion capabilities of A549 cells by the wound healing assay and transwell-matrigel invasion chambers.Results:After stimulating with TGF-β1,almost all A549 cells changed to the mesenchymal phenotype and acquired more migration and invasion capabilities.These cells also had higher eIF5A-2 protein expression.Down-regulation of eIF5A-2 expression with eIF5A-2 siRNA transfection could change the cells from mesenchymal to epithelial phenotype and decrease tumor cell migration and invasive capabilities significantly.Conclusions:The expression of eIF5A-2 was up-regulated following EMT phenotype changes in A549 cells,which correlated with enhanced tumor invasion and metastatic capabilities.Furthermore,in the A549 cell line,the process of EMT phenotype change could be reversed by eIF5A-2 siRNA,with a consequent weakening of both invasive and metastatic capabilities.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.22005253)。
文摘Recently,an emerging category green of energetic material ammonium dinitramide(ADN)has exhibited promising application in propellants due to its outstanding merits in energy release and environmental friendliness.It can be considered to substitute traditional oxidizer of ammonium perchlorate(AP)in military systems and aerospace.In this paper,a novel spherical energetic composite ADN/copper alginate(CA)with a microporous structure was designed and prepared by the W/O gel emulsion method,and a desirable porous microsphere structure was obtained.Multiple characterization techniques were used to investigate the structure and properties of ADN/CA composites.The results showed that ADN crystals were homogeneously encapsulated in an alginate-gel matrix.Thermal decomposition temperature was reduced to 151.7℃compared to ADN,while the activation energy of them was reduced from 129.73 k J/mol(ADN)to 107.50 k J/mol(ADN/CA-4).In addition,as-prepared samples had lower impact and frictional sensitivity than ADN.The mechanism of sensitivity reduction and decomposition are also discussed.Constant-volume combustion tests show that peak pressure of the ADN/CA-4 achieves 253.4 k Pa and pressurization rate of 2750.4 k Pa/s.Hence,this has a promising application in improving the combustion performance and safety performance of solid propellants.
基金Project supported by the Natural Science Fundation of Ningbo (No. 2011A610052)the Zhejiang Provincial Natural Science Fundation (No. LY12H16002) of China
文摘Background:Epithelial-mesenchymal transition(EMT) is believed to be the critical process in malignant tumor invasion and metastases,and has a great influence on improving the survival rate in non-small-cell lung cancer(NSCLC) patients.Recent studies suggested that eukaryotic initiation factor 5A-2(eIF5A-2) might serve as an adverse prognostic marker of survival.We detected eIF5A-2 in NSCLC A549 cells,and found that the invasive capability correlates with the eIF5A-2 expression.Methods:Transforming growth factor(TGF)-β1 was used to induce EMT in A549 cells.Western blotting,immunofluorescence,wound healing assay,and transwell-matrigel invasion chambers were used to identify phenotype changes.Western blotting was also used to observe changes of the expression of eIF5A-2.We down-regulated the eIF5A-2 expression using an eIF5A-2 siRNA and identified the phenotype changes by western blotting and immunofluorescence.We tested the change of migration and invasion capabilities of A549 cells by the wound healing assay and transwell-matrigel invasion chambers.Results:After stimulating with TGF-β1,almost all A549 cells changed to the mesenchymal phenotype and acquired more migration and invasion capabilities.These cells also had higher eIF5A-2 protein expression.Down-regulation of eIF5A-2 expression with eIF5A-2 siRNA transfection could change the cells from mesenchymal to epithelial phenotype and decrease tumor cell migration and invasive capabilities significantly.Conclusions:The expression of eIF5A-2 was up-regulated following EMT phenotype changes in A549 cells,which correlated with enhanced tumor invasion and metastatic capabilities.Furthermore,in the A549 cell line,the process of EMT phenotype change could be reversed by eIF5A-2 siRNA,with a consequent weakening of both invasive and metastatic capabilities.
