A new mononuclear Cu（II） complex, [Cu（L）] （H2L = 4,4′,6,6v-tetrabromo-2,2′- [ethylenedioxybis（nitrilomethylidyne）]diphenol）, has been synthesized and structurally characterized. X-ray crystal structure of th...A new mononuclear Cu（II） complex, [Cu（L）] （H2L = 4,4′,6,6v-tetrabromo-2,2′- [ethylenedioxybis（nitrilomethylidyne）]diphenol）, has been synthesized and structurally characterized. X-ray crystal structure of the complex reveals that the Cu（Ⅱ） ion is four-coordinated by two oxygen atoms and two nitrogen atoms from L2- unit. Crystallographic data： monoclinic, space group P21/n with a = 14.076（2）, b = 6.9801（14）, c = 19.858 （2） A, β= 107.613（2）°, C16n10Br4CuN2O4, Mr = 677.44, V = 1859.6（5） A3, Dc = 2.420 g/cm3,μ = 9.796 mm^-1, F（000） = 1284, Z = 4, the final R = 0.0516 and wR = 0.0938 for 1879 observed reflections with I 〉 2σ（/）. The dihedral angel between the two coordination planes of Cu（1）-N（2）--O（4） and Cu（1 ）-N（ 1 ）-O（3）） is 30.08（6）°.展开更多
On the tenth conference of the standingcommittee of Guangzhou Municipal People’sCongress on August 27, 1996, the announcement by Li Ziliu, who was then Mayor ofGuangzhou, that he would resign the mayorpost, won an un...On the tenth conference of the standingcommittee of Guangzhou Municipal People’sCongress on August 27, 1996, the announcement by Li Ziliu, who was then Mayor ofGuangzhou, that he would resign the mayorpost, won an unusual three-minute applausesfrom representatives of the conference. Theapplauses containing representatives’ respectsand appreciations to him , moved Li. When he took the positon six years ago,Li, who came from the economically booming Sunde City in the Pear River Delta, wasgiven a nickname as "rural mayor".展开更多
Poly (oligoether methacrylate-co-acrylonitrile) s, P (MEOn- AN), with oligoether pendants of different lengths were synthesized and the ion conduction property of their Li-salt complexes was studied as the function of...Poly (oligoether methacrylate-co-acrylonitrile) s, P (MEOn- AN), with oligoether pendants of different lengths were synthesized and the ion conduction property of their Li-salt complexes was studied as the function of polymer structure. At proper copolymer composition, lithium concentration and pendant length, the ion conductivity reaches 7.0×10^(-5)S/cm at ambient temperature, together with improved mechanical strength. The ion transport in the polymer media is assisted by segmental relaxation, which is confirmed both by the consistency between ion conductivity and T_g and by the study of TSC.展开更多
The cathode material Li 1+ x Mn 2O 4 was prepared by a modified citric acid complexation method. The influences of temperature, sintering time and n (Li)/ n (Mn) ratio on the structure of the products have been explor...The cathode material Li 1+ x Mn 2O 4 was prepared by a modified citric acid complexation method. The influences of temperature, sintering time and n (Li)/ n (Mn) ratio on the structure of the products have been explored, characterized and tested by XRD, TEM, BET measurements. The sample sintered at 750 ℃ for 12 h had greater charge/discharge capacity, better cyclic stability under electric current charge/discharge cycle. The initial capacity reached 120 mA·h/g with the charge/discharge efficieney of 98% and maintained 115 mA·h/g after 50 cycles.展开更多
Li1.06Co0.05Cr0.1Mn1.85O4 powders were prepared by heating metal-urea nitrate complexes precursors. The influence of synthesis conditions on the structural and electrochemical properties of Li1.06Co0.05Cr0.1Mn1.85O4 w...Li1.06Co0.05Cr0.1Mn1.85O4 powders were prepared by heating metal-urea nitrate complexes precursors. The influence of synthesis conditions on the structural and electrochemical properties of Li1.06Co0.05Cr0.1Mn1.85O4 was investigated by X-ray diffraction, scanning electron microscopy and charge-discharge experiments. The powders were well crystallized and with a narrow particle size distribution and regular morphology about 60 nm. Electrochemical performances indicated that Li1.06Co0.05Cr0.1Mn1.85O4 delivered a high capacity of 191 mAh·g-1 at 14th cycle due to additional 3 V (vs Li) plateau, 145 mAh·g-1 at 22st cycle. The results show that there are two pairs of voltammetric wave (centered at 4 V (vs Li)) and a pairs of voltammetric wave (centered at 3 V (vs Li)), indicating an excellent reversibility.展开更多
The ion-exchanger LiMg0.5Mn1.5O4 of spinel type was prepared by the common precipitation/heated crystallization method, and was acid modified. Its properties of ion-exchange for alkali ions such as saturation capacity...The ion-exchanger LiMg0.5Mn1.5O4 of spinel type was prepared by the common precipitation/heated crystallization method, and was acid modified. Its properties of ion-exchange for alkali ions such as saturation capacity of exchange, distribution coefficient and the pH titration curve have been determined. LiMg0.5Mn1.5O4 was characterized by X-ray diffraction. These results show that this inorganic ion-exchanger has better remembering and selectivity of ion exchange, and higher capacity of exchange for Li+, the capacity of exchange reaches 32.39 mg·g-1 for Li+.展开更多
基金This work was supported by the Foundation of Education Department of Gansu Province (No. 0604-01)the 'Qing Lan' Talent Engineering Funds of Lanzhou Jiaotong University (No. QL-03-01A)
文摘A new mononuclear Cu（II） complex, [Cu（L）] （H2L = 4,4′,6,6v-tetrabromo-2,2′- [ethylenedioxybis（nitrilomethylidyne）]diphenol）, has been synthesized and structurally characterized. X-ray crystal structure of the complex reveals that the Cu（Ⅱ） ion is four-coordinated by two oxygen atoms and two nitrogen atoms from L2- unit. Crystallographic data： monoclinic, space group P21/n with a = 14.076（2）, b = 6.9801（14）, c = 19.858 （2） A, β= 107.613（2）°, C16n10Br4CuN2O4, Mr = 677.44, V = 1859.6（5） A3, Dc = 2.420 g/cm3,μ = 9.796 mm^-1, F（000） = 1284, Z = 4, the final R = 0.0516 and wR = 0.0938 for 1879 observed reflections with I 〉 2σ（/）. The dihedral angel between the two coordination planes of Cu（1）-N（2）--O（4） and Cu（1 ）-N（ 1 ）-O（3）） is 30.08（6）°.
文摘On the tenth conference of the standingcommittee of Guangzhou Municipal People’sCongress on August 27, 1996, the announcement by Li Ziliu, who was then Mayor ofGuangzhou, that he would resign the mayorpost, won an unusual three-minute applausesfrom representatives of the conference. Theapplauses containing representatives’ respectsand appreciations to him , moved Li. When he took the positon six years ago,Li, who came from the economically booming Sunde City in the Pear River Delta, wasgiven a nickname as "rural mayor".
文摘Poly (oligoether methacrylate-co-acrylonitrile) s, P (MEOn- AN), with oligoether pendants of different lengths were synthesized and the ion conduction property of their Li-salt complexes was studied as the function of polymer structure. At proper copolymer composition, lithium concentration and pendant length, the ion conductivity reaches 7.0×10^(-5)S/cm at ambient temperature, together with improved mechanical strength. The ion transport in the polymer media is assisted by segmental relaxation, which is confirmed both by the consistency between ion conductivity and T_g and by the study of TSC.
文摘The cathode material Li 1+ x Mn 2O 4 was prepared by a modified citric acid complexation method. The influences of temperature, sintering time and n (Li)/ n (Mn) ratio on the structure of the products have been explored, characterized and tested by XRD, TEM, BET measurements. The sample sintered at 750 ℃ for 12 h had greater charge/discharge capacity, better cyclic stability under electric current charge/discharge cycle. The initial capacity reached 120 mA·h/g with the charge/discharge efficieney of 98% and maintained 115 mA·h/g after 50 cycles.
文摘Li1.06Co0.05Cr0.1Mn1.85O4 powders were prepared by heating metal-urea nitrate complexes precursors. The influence of synthesis conditions on the structural and electrochemical properties of Li1.06Co0.05Cr0.1Mn1.85O4 was investigated by X-ray diffraction, scanning electron microscopy and charge-discharge experiments. The powders were well crystallized and with a narrow particle size distribution and regular morphology about 60 nm. Electrochemical performances indicated that Li1.06Co0.05Cr0.1Mn1.85O4 delivered a high capacity of 191 mAh·g-1 at 14th cycle due to additional 3 V (vs Li) plateau, 145 mAh·g-1 at 22st cycle. The results show that there are two pairs of voltammetric wave (centered at 4 V (vs Li)) and a pairs of voltammetric wave (centered at 3 V (vs Li)), indicating an excellent reversibility.
文摘The ion-exchanger LiMg0.5Mn1.5O4 of spinel type was prepared by the common precipitation/heated crystallization method, and was acid modified. Its properties of ion-exchange for alkali ions such as saturation capacity of exchange, distribution coefficient and the pH titration curve have been determined. LiMg0.5Mn1.5O4 was characterized by X-ray diffraction. These results show that this inorganic ion-exchanger has better remembering and selectivity of ion exchange, and higher capacity of exchange for Li+, the capacity of exchange reaches 32.39 mg·g-1 for Li+.
