The Clar covering polynomial of hexagonal systems is a recently proposed1,2 concept which contains much more topological properties of condensed aromatic hydrocarbons, such as Kekule structure count, Clar number, firs...The Clar covering polynomial of hexagonal systems is a recently proposed1,2 concept which contains much more topological properties of condensed aromatic hydrocarbons, such as Kekule structure count, Clar number, first Herndon number, etc. It is shown that this polynomial can be used for calculating the resonance energy of condensed aromatic hydrocarbons with better accuracy.展开更多
[Objective] The present experiment was conducted to study the effects of bamboo vinegar on seed germination and seedling growth of different flue-cured to- bacco varieties, so as to provide some references for its app...[Objective] The present experiment was conducted to study the effects of bamboo vinegar on seed germination and seedling growth of different flue-cured to- bacco varieties, so as to provide some references for its application in tobacco pro- duction. [Method] By using indoor culture dish method and greenhouse seedling- raising plate culture,four different concentrations of bamboo vinegar dilution （50, 100, 200 and 400 times）were designed and clean water was used as the control （CK）. The germination indices of Yunyan 97, Guiyan 2, Jiucaiping 2 and Bina 1 were de- termined after seed germinating. The seedling growth indices of Yunyan 97 were investigated after 10 days of spaying bamboo vinegar on seedling leaves at the 3r~ time. [Result] Compared with CK, different bamboo vinegar dilutions could inhibit the seed germination and seedling growth of all flue-cured tobacco varieties. The seed germination rate and index, vigor index, whole length, root length, stem length and fresh weight of seedlings of all varieties presented decreasing trend to varying de- grees, moreover, most of them reached significant level. Compared with CK, spray- ing different concentrations of bamboo vinegar dilution at the seedling stage could improve the quality of seedlings. In all bamboo vinegar treatments, the plant height, the maximum leaf length and root volume under 100 times dilution treatment were the highest with 3.36 and 10.14 cm, and 0.92 ml, respectively. And the stem girth, dry weight and the maximum leaf width of seedlings under 400 times dilution treat- ment also showed the highest with 1.82 cm, 0.262 g and 5.74 cm, respectively. [Conclusion] Supplying different concentrations of bamboo vinegar solution on culture dish could inhibit the seed germination and seedling growth of flue-cured tobacco, while spraying 100-400 times bamboo vinegar solution to leaves could promote the seedling growth and improve the quality of Yunyan 97 to varying degrees.展开更多
Aromatic diimide dyes are an attractive class of redox-active organic molecules for lithium-ion batteries,whose battery performances(stabilities,conductivities and cyclicities) are strongly dependent on the sizes of t...Aromatic diimide dyes are an attractive class of redox-active organic molecules for lithium-ion batteries,whose battery performances(stabilities,conductivities and cyclicities) are strongly dependent on the sizes of their π-systems.However,due to the different Clar’s structures possessed,three vertically7 r-extended aromatic diimides,namely,naphthalene diimide(two one-electron reductions),perylene diimide and terrylene diimide(two one-electron reductions),exhibit different electronic redox mechanisms when served as cathode materials in organic lithium-ion batteries.Herein,we have studied carefully the different electrochemical characteristics of the three aromatic diimides through experimental and theoretical calculations.Their battery present different shape of charge/discharge curves resulting from stability of their reduction state during charge/discharge process.Terrylene diimide shows better cycle and rate capacities than those of naphthalene diimide and perylene diimide,which could be attributed to the more energies released during terrylene diimide combining with lithium ions than those of other two diimides.展开更多
基金Project supported by the National Natural Science Foundation of China.
文摘The Clar covering polynomial of hexagonal systems is a recently proposed1,2 concept which contains much more topological properties of condensed aromatic hydrocarbons, such as Kekule structure count, Clar number, first Herndon number, etc. It is shown that this polynomial can be used for calculating the resonance energy of condensed aromatic hydrocarbons with better accuracy.
基金Supported by Science and Technology Project of Guizhou Tobacco Monopoly Bureau-"The Integration and Application of Transplanting Technology for Resisting Spring Drought in Weining Tobacco-growing Area"(201226)~~
文摘[Objective] The present experiment was conducted to study the effects of bamboo vinegar on seed germination and seedling growth of different flue-cured to- bacco varieties, so as to provide some references for its application in tobacco pro- duction. [Method] By using indoor culture dish method and greenhouse seedling- raising plate culture,four different concentrations of bamboo vinegar dilution （50, 100, 200 and 400 times）were designed and clean water was used as the control （CK）. The germination indices of Yunyan 97, Guiyan 2, Jiucaiping 2 and Bina 1 were de- termined after seed germinating. The seedling growth indices of Yunyan 97 were investigated after 10 days of spaying bamboo vinegar on seedling leaves at the 3r~ time. [Result] Compared with CK, different bamboo vinegar dilutions could inhibit the seed germination and seedling growth of all flue-cured tobacco varieties. The seed germination rate and index, vigor index, whole length, root length, stem length and fresh weight of seedlings of all varieties presented decreasing trend to varying de- grees, moreover, most of them reached significant level. Compared with CK, spray- ing different concentrations of bamboo vinegar dilution at the seedling stage could improve the quality of seedlings. In all bamboo vinegar treatments, the plant height, the maximum leaf length and root volume under 100 times dilution treatment were the highest with 3.36 and 10.14 cm, and 0.92 ml, respectively. And the stem girth, dry weight and the maximum leaf width of seedlings under 400 times dilution treat- ment also showed the highest with 1.82 cm, 0.262 g and 5.74 cm, respectively. [Conclusion] Supplying different concentrations of bamboo vinegar solution on culture dish could inhibit the seed germination and seedling growth of flue-cured tobacco, while spraying 100-400 times bamboo vinegar solution to leaves could promote the seedling growth and improve the quality of Yunyan 97 to varying degrees.
基金supported by the National Natural Science Foundation of China (No.21572032)Program for New Century Excellent Talents in Fujian Province University+2 种基金Natural Science Foundation of Fujian Province (Nos.2018J01431 and 2018J01690)the Foundation of Science and Technology on Sanming Institute of Fluorochemical Industry (No.FCIT201706GR)Excellent Youth Exchange Program of China Association for Science and Technology in 2017
文摘Aromatic diimide dyes are an attractive class of redox-active organic molecules for lithium-ion batteries,whose battery performances(stabilities,conductivities and cyclicities) are strongly dependent on the sizes of their π-systems.However,due to the different Clar’s structures possessed,three vertically7 r-extended aromatic diimides,namely,naphthalene diimide(two one-electron reductions),perylene diimide and terrylene diimide(two one-electron reductions),exhibit different electronic redox mechanisms when served as cathode materials in organic lithium-ion batteries.Herein,we have studied carefully the different electrochemical characteristics of the three aromatic diimides through experimental and theoretical calculations.Their battery present different shape of charge/discharge curves resulting from stability of their reduction state during charge/discharge process.Terrylene diimide shows better cycle and rate capacities than those of naphthalene diimide and perylene diimide,which could be attributed to the more energies released during terrylene diimide combining with lithium ions than those of other two diimides.
