Thermodynamic analyses and kinetic studies were performed on zinc oxide ore treatment by （NH4）2SO4 roasting technology. The results show that it is theoretically feasible to realize a roasting reaction between the z...Thermodynamic analyses and kinetic studies were performed on zinc oxide ore treatment by （NH4）2SO4 roasting technology. The results show that it is theoretically feasible to realize a roasting reaction between the zinc oxide ore and （NH4）2SO4 in a temperature range of 573-723 K. The effects of reaction temperature and particle size on the extraction rate of zinc were also examined. It is found that a surface chemical reaction is the rate-controlling step in roasting kinetics. The calculated activation energy of this process is about 45.57 kJ/mol, and the kinetic model can be expressed as follows： 1 - （1 - α）1/3 = 30.85 exp（-45.57/RT）·t. An extraction ratio of zinc as high as 92% could be achieved under the optimum conditions.展开更多
Various aromatic α-keto esters were rapidly and selectively reduced to aromatic α-hydroxy esters by commercially available zinc dust and ammonium formate in the presence of other functional groups such as halogens, ...Various aromatic α-keto esters were rapidly and selectively reduced to aromatic α-hydroxy esters by commercially available zinc dust and ammonium formate in the presence of other functional groups such as halogens, methoxy and esters.展开更多
A new method for indirect determination of cetyl-trimethyl ammonium bromide (CTMAB) with NaCl and NH4SCN by floatation and separation of zinc has been studied. The study shows that Zn(II) can associate with NH4SCN an...A new method for indirect determination of cetyl-trimethyl ammonium bromide (CTMAB) with NaCl and NH4SCN by floatation and separation of zinc has been studied. The study shows that Zn(II) can associate with NH4SCN and CTMAB to form insoluble ternary ion-association complex, and the precipitate can float on the surface of the liquid phase. A good linear relationship is observed between the floatation yield (E%) of Zn(II) and the amount of CTMAB. On the ground, CTMAB can be indirectly determined by determining E% of Zn(II). The results were satisfactory.展开更多
研究了聚磷酸铵APP、三聚氰胺氰尿酸盐MCA、乙酰丙酮锌以及ABS高胶粉对磷-氮复配无卤阻燃ABS材料的阻燃性能、力学性能及热学特性的影响。实验表明单独使用聚磷酸铵APP阻燃剂对ABS材料进行阻燃改性效果一般,阻燃等级无法达到V-0级别。将...研究了聚磷酸铵APP、三聚氰胺氰尿酸盐MCA、乙酰丙酮锌以及ABS高胶粉对磷-氮复配无卤阻燃ABS材料的阻燃性能、力学性能及热学特性的影响。实验表明单独使用聚磷酸铵APP阻燃剂对ABS材料进行阻燃改性效果一般,阻燃等级无法达到V-0级别。将APP与MCA复配使用后材料阻燃效果良好,能够达到1.6 mm V-0级别。在无卤阻燃ABS体系中添加部分ABS高胶粉能够改善阻燃ABS抗冲击性能不足的缺点,但会降低阻燃效果,添加部分乙酰丙酮锌能够将该影响消除,同时能提高阻燃ABS的抗冲击性能。展开更多
基金financially supported by a Project Supported by the National Natural Science Foundation of China (No. 51204054)the Fundamental Research Funds for the Central Universities of China (N110402012)the National Basic Research Program of China (No. 2007CB613603)
文摘Thermodynamic analyses and kinetic studies were performed on zinc oxide ore treatment by （NH4）2SO4 roasting technology. The results show that it is theoretically feasible to realize a roasting reaction between the zinc oxide ore and （NH4）2SO4 in a temperature range of 573-723 K. The effects of reaction temperature and particle size on the extraction rate of zinc were also examined. It is found that a surface chemical reaction is the rate-controlling step in roasting kinetics. The calculated activation energy of this process is about 45.57 kJ/mol, and the kinetic model can be expressed as follows： 1 - （1 - α）1/3 = 30.85 exp（-45.57/RT）·t. An extraction ratio of zinc as high as 92% could be achieved under the optimum conditions.
文摘Various aromatic α-keto esters were rapidly and selectively reduced to aromatic α-hydroxy esters by commercially available zinc dust and ammonium formate in the presence of other functional groups such as halogens, methoxy and esters.
文摘A new method for indirect determination of cetyl-trimethyl ammonium bromide (CTMAB) with NaCl and NH4SCN by floatation and separation of zinc has been studied. The study shows that Zn(II) can associate with NH4SCN and CTMAB to form insoluble ternary ion-association complex, and the precipitate can float on the surface of the liquid phase. A good linear relationship is observed between the floatation yield (E%) of Zn(II) and the amount of CTMAB. On the ground, CTMAB can be indirectly determined by determining E% of Zn(II). The results were satisfactory.
基金supported by the National Natural Science Foundation of the People’s Republic of China“Data-driven high-throughput screening of cathode materials for Zn-ion batteries”(22065032)Undergraduate Education and Teaching Research and Reform Project of Universities in Xinjiang Uygur Autonomous Region“Innovative research on ideological and political education in courses and virtual simulation technology in structural chemistry”(XJGXPTJG-202205).
文摘研究了聚磷酸铵APP、三聚氰胺氰尿酸盐MCA、乙酰丙酮锌以及ABS高胶粉对磷-氮复配无卤阻燃ABS材料的阻燃性能、力学性能及热学特性的影响。实验表明单独使用聚磷酸铵APP阻燃剂对ABS材料进行阻燃改性效果一般,阻燃等级无法达到V-0级别。将APP与MCA复配使用后材料阻燃效果良好,能够达到1.6 mm V-0级别。在无卤阻燃ABS体系中添加部分ABS高胶粉能够改善阻燃ABS抗冲击性能不足的缺点,但会降低阻燃效果,添加部分乙酰丙酮锌能够将该影响消除,同时能提高阻燃ABS的抗冲击性能。
