Tin(Sn)isotope geochemistry has great potential in tracing geological processes.However,lack of equilibrium Sn isotope fractionation factors of various Sn species limits the development of Sn isotope geochemistry.Equi...Tin(Sn)isotope geochemistry has great potential in tracing geological processes.However,lack of equilibrium Sn isotope fractionation factors of various Sn species limits the development of Sn isotope geochemistry.Equilibrium Sn isotope fractionation factors(124Sn/116Sn and 122Sn/116Sn)among various Sn(II,IV)complexes in aqueous solution were calculated using first-principles calculations.The results show that the oxidation states and the change of Sn(II,IV)species in hydrothermal fluids are the main factors leading to tin isotope fractionation in hydrothermal systems.For the Sn(IV)complexes,Sn isotope fractionation factors depend on the number of H2O molecules.For the Sn(II)complexes,the Sn isotope fractionation between Sn(II)−F,Sn(II)−Cl and Sn(II)−OH complexes is mainly affected by the bond length and the coordination number of anion,whereas the difference in 1000lnβvalues of Sn(II)−SO4 and Sn(II)−CO_(3) complexes is insignificant with the change of anion coordination number.By comparing the 1000lnβvalues of all Sn(II,IV)complexes,the enrichment trend in heavy Sn isotopes is Sn(IV)complexes>Sn(II)complexes.The equilibrium Sn isotopic fractionation factors enhance our understanding of the tin transportation and enrichment processes in hydrothermal systems.展开更多
以丙烯酰胺为单体,对腐植酸钠采用接枝共聚法改性。以改性腐植酸钠作为填料,制备了低密度聚乙烯（LDPE）/改性腐植酸钠复合材料,并对其结构与性能进行了研究。结果表明：改性腐植酸钠的界面接触角明显增大;与LDPE基体相比,LDPE/5%改性...以丙烯酰胺为单体,对腐植酸钠采用接枝共聚法改性。以改性腐植酸钠作为填料,制备了低密度聚乙烯（LDPE）/改性腐植酸钠复合材料,并对其结构与性能进行了研究。结果表明：改性腐植酸钠的界面接触角明显增大;与LDPE基体相比,LDPE/5%改性腐植酸钠复合材料的拉伸强度提高至23.14 MPa,断裂伸长率提高至72.51%,冲击强度提高至10.025 k J/m^2,结晶度提高至28.10%,热分解温度提高至479.91℃。由于具有较高黏性腐植酸钠-丙烯酰胺接枝聚合物的加入,LDPE复合材料具有比LDPE基体更高的剪切黏性。展开更多
基金supported financially by the National Natural Science Foundation of China(92062218,41822304).
文摘Tin(Sn)isotope geochemistry has great potential in tracing geological processes.However,lack of equilibrium Sn isotope fractionation factors of various Sn species limits the development of Sn isotope geochemistry.Equilibrium Sn isotope fractionation factors(124Sn/116Sn and 122Sn/116Sn)among various Sn(II,IV)complexes in aqueous solution were calculated using first-principles calculations.The results show that the oxidation states and the change of Sn(II,IV)species in hydrothermal fluids are the main factors leading to tin isotope fractionation in hydrothermal systems.For the Sn(IV)complexes,Sn isotope fractionation factors depend on the number of H2O molecules.For the Sn(II)complexes,the Sn isotope fractionation between Sn(II)−F,Sn(II)−Cl and Sn(II)−OH complexes is mainly affected by the bond length and the coordination number of anion,whereas the difference in 1000lnβvalues of Sn(II)−SO4 and Sn(II)−CO_(3) complexes is insignificant with the change of anion coordination number.By comparing the 1000lnβvalues of all Sn(II,IV)complexes,the enrichment trend in heavy Sn isotopes is Sn(IV)complexes>Sn(II)complexes.The equilibrium Sn isotopic fractionation factors enhance our understanding of the tin transportation and enrichment processes in hydrothermal systems.
文摘以丙烯酰胺为单体,对腐植酸钠采用接枝共聚法改性。以改性腐植酸钠作为填料,制备了低密度聚乙烯（LDPE）/改性腐植酸钠复合材料,并对其结构与性能进行了研究。结果表明：改性腐植酸钠的界面接触角明显增大;与LDPE基体相比,LDPE/5%改性腐植酸钠复合材料的拉伸强度提高至23.14 MPa,断裂伸长率提高至72.51%,冲击强度提高至10.025 k J/m^2,结晶度提高至28.10%,热分解温度提高至479.91℃。由于具有较高黏性腐植酸钠-丙烯酰胺接枝聚合物的加入,LDPE复合材料具有比LDPE基体更高的剪切黏性。
