The redox initiation system for polyacrylate sodium of high molecular mass was designed and its effect with varying component dosage on the degree of polymerization was investigated. The results show that the proper t...The redox initiation system for polyacrylate sodium of high molecular mass was designed and its effect with varying component dosage on the degree of polymerization was investigated. The results show that the proper type and amount of inorganic salt, as well as amine initiator, are conductive to the increase of degree of polymerization. The fine ingredient of the initiation system is as follows:the dosages of amine, persulphate and inorganic salt are 0.75%, 0.10% and 1.00% by mass based on acryl acid respectively, the molar ratio of sulphite to the persulphate is 1:1. Under such conditions the degree of polyacrylate can reach 7.43×107 with a acceptable polymerization time for industrial production.展开更多
By using nonequilibrium Green's function method and first-principles calculations, the electronic transport properties of doped C60 molecular devices were investigated. It is revealed that the C60 molecular devices s...By using nonequilibrium Green's function method and first-principles calculations, the electronic transport properties of doped C60 molecular devices were investigated. It is revealed that the C60 molecular devices show the metal behavior due to the interaction between the C60 molecule and the metal electrode. The current-voltage curve displays a linear behavior at low bias, and the currents have the relation of MI〉M3〉M4〉M2 when the bias voltage is lower than 0.6 V. Electronic transport properties are affected greatly by the doped atoms. Negative differential resistance is found in a certain bias range for C60 and C58BN molecular devices, but cannot be observed in C59B and C59N molecular devices. These unconventional effects can be used to design novel nanoelectronic devices.展开更多
基金Project(G199906490 2) supported by the National Key Fundamental Research and Development Program of China
文摘The redox initiation system for polyacrylate sodium of high molecular mass was designed and its effect with varying component dosage on the degree of polymerization was investigated. The results show that the proper type and amount of inorganic salt, as well as amine initiator, are conductive to the increase of degree of polymerization. The fine ingredient of the initiation system is as follows:the dosages of amine, persulphate and inorganic salt are 0.75%, 0.10% and 1.00% by mass based on acryl acid respectively, the molar ratio of sulphite to the persulphate is 1:1. Under such conditions the degree of polyacrylate can reach 7.43×107 with a acceptable polymerization time for industrial production.
基金Project(07JJ3102) supported by the Natural Science Foundation of Hunan Province, ChinaProject(1343-74236000006) supported by the Graduate Foundation of Hunan Province, ChinaProject(11MY20) supported by the Mittal Entrepreneurship Program of China
文摘By using nonequilibrium Green's function method and first-principles calculations, the electronic transport properties of doped C60 molecular devices were investigated. It is revealed that the C60 molecular devices show the metal behavior due to the interaction between the C60 molecule and the metal electrode. The current-voltage curve displays a linear behavior at low bias, and the currents have the relation of MI〉M3〉M4〉M2 when the bias voltage is lower than 0.6 V. Electronic transport properties are affected greatly by the doped atoms. Negative differential resistance is found in a certain bias range for C60 and C58BN molecular devices, but cannot be observed in C59B and C59N molecular devices. These unconventional effects can be used to design novel nanoelectronic devices.