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121.
LU Shi-xiang JIN Guo-xin ** HU Ning-hai JIA Heng-qing . Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun P. R. China . College of Chemistry Jinlin University Changchun P. R. China 《高等学校化学研究》2002,18(4)
IntroductionThe chemistry of chalcogen organometalliccomplexs has become one of the most activebranches in modern chemistry[1] .Itnot only showsthe coordinate variability of organometalliccomplexes but also is applied to studying thereaction mechanism of biologic enzyme[2 ] and thecatalysis of dehydrogenation or hydrogenation inindustry[3] .It is known that transition metalcomplexes react with cyclopentadienyl orsubstituted cyclopentadienyl to form halfsandwichcomplexes with different structur… 相似文献
122.
WEI Ping-Rong JIA Lu LIU Chang-Rang FAN Yao-TingDepartment of Chemistry Zhengzhou University Zhengzhou Henan ChinaGAO SongResearch Center of Rare Earth Chemistry Peking University Beijing China 《中国化学》1994,12(6):503-508
The two complexes [Ni(oxen)Cu(L)2](ClO4)2.xH2O (L=2,2'-bipyridyl(bpy), 1,10-phenanthroline(phen)) have been synthesized, where oxen is N,N'-bis(2-aminoethyl)oxamido di-anion. The crystal structure of [Ni(oxen)Cu(bpy)2](ClO4)2.CH3OH has been determined by X-ray diffraction method. The crystal is triclinic system, space group P1 with a=12.179(1),b=12.298(2), c=11.476(2) A, a=97.57(1), B=97.52(1), 7=80.29(2), V=1669.04(67) A3, Z=2, Dcalcd=1.667 g/cm3. The structure has been refined to final R of 0.076 and Rw of 0.080, respectively. The complexes have an extended oxamido-bridged structure and consist of Ni(Ⅱ) ion in a square planar environment and Cu(Ⅱ) ion in a distorted octahedral environment. 相似文献
123.
CuAl2O4 powder synthesis by sol-gel method and its photodegradation property under visible light irradiation 总被引:1,自引:0,他引:1
Jiang Yanyan Li Jinggang Sui Xiaotao Ning Guiling Wang Chengyu Gu Xiumei 《Journal of Sol-Gel Science and Technology》2007,42(1):41-45
Nanocrystalline spinel CuAl2O4 powders were prepared by sol-gel method from nitrate Cu(NO3)2·3H2O, Al(NO3)3·9H2O and complex C6H8O7·H2O. Sintering was carried out at 400, 500, 600, 700, 800°C respectively for 2 h in air. The XRD patterns started to appear
CuAl2O4 peaks after sintering of 500°C and consist of only CuAl2O4 peaks as spinel crystal after sintering of 700°C. The powders were analyzed by TEM and UV-vis diffuse reflectance spectrum
to be round, about 10–30 nm in size and Eg=1.77 eV. Photodegradation property of nanocrystalline CuAl2O4 powders was investigated by using methyl orange as model pollutant and mercury lamp (λ>400 nm) as energy source. The results
indicated that CuAl2O4 powders sintered at 700°C had the excellent visible photocatalytic property. Under the irradiation of visible light, methyl
orange could be degraded 97% in 120 min. 相似文献
124.
The effects of variant counterions with ionic strength of 0.05, 0.10, 0.20 and 0.25 mol·kg^-1 on the stability and particle size of silica sols have been studied using the traditional methods of Ubbelohde viscosity measurement, TEM and titration respectively, finding that the stability and particle size of the silica sols are all concerned with the acidic, positively electric properties and the sizes of the counterions, as well as the attraction between the counterions and surface silicon hydroxyl groups of the silica sols. The small positively charged counterions lead to the decrease in particle sizes, making the silica sol the most stable. But the larger weakly acidic counterions can restrict the particle sizes of the silica sols and easily make the sols coagulate. It was also found that there existed a linear relationship between log r and log η, which has not ever been reported. The effect of temperature on the stability and particle sizes was also discussed. 相似文献
125.
锂离子电池正极材料LiMn2O4的低热固相合成与性能表征 总被引:6,自引:0,他引:6
锂离子电池具有比能量高、环境污染小等优点,广泛应用于手提电话、便携式电脑、摄像机等设备中。其正极材料的研究是锂离子电池的研究重点。层状结构的LiCoO2、LiNiO2和尖晶石结构的LiMn2O4是仅有的三种能在3.5V以上电位可嵌入Li的正极材料[1~3]。目前市售的锂离子电池主要采用LiCoO2作正极材料,但由于Co资源缺乏和价格相对昂贵,而锰资源丰富,价格低廉且无毒,对环境友好,因此世界各国都在大力进行以LiMn2O4为正极材料的锂离子电池的实用化研究。LiMn2O4传统的制备方法是高温固相反应合成法[4~7],但由于Mn的变价多,与Li形成贫Li或… 相似文献
126.
在溶剂热条件下,基于芳香四羧酸合成了2种新颖的配位聚合物:{[Zn2(tptc)(1,4-bimb)2]·H2O}n(1)和{[Ni(tptc)0.5(1,2-bimb)(H2O)]·H2O}n(2),其中,tptc为对-三联苯-3,3″,5,5″-四羧酸,1,4-bimb为1,4-二(咪唑-1-亚甲基)苯,1,2-bimb为1,2-二(咪唑-1-亚甲基)苯。结构分析表明,1为三维结构,拓扑符号为(86);2为二维层状网络,通过氢键相互作用进一步扩展为三维超分子结构。此外,我们还研究了1对阳离子、阴离子的荧光感应以及2的磁性质。 相似文献
127.
128.
The apparent solubility (S), concentration-average diffusivity (D), and permeability (P), for C0_2, CH_4 and N_2 through PPO and aryl-brominated PPO at 35℃for pressure ranging from 1 to 26 atm are reported. It is found that P, D, and S of the membranes to all the three gases vary with the extent of bromination. S increases with the increase of the percent of bromine in each case, but D to CO_2 increases remarkably only at higher degree of brominafion, and therefore, P to CO_2 is increased by more than 100% over a wide range ofpressure in the case. The solubility data are well described by the dual mode sorption model. It is found that the gas molecules sorbed by the Langmuir mode are relatively more immobilized and the contribution of the nonequilibrinm character of the polymer to gas permeation increases obviously for CO_2 and is hardly changed for CH_4 with increasing bromine content. These observations are interpreted in terms of changes in specific free volume (SFV)and the cohesive energy density (CED) of the polymers. 相似文献
129.
采用Cerius 2中的GGA/PW91密度泛函方法对具有D6h对称性的C36及其衍生物Y@C36进行结构全优化, 系统地分析了Y在C36笼内不同占位时系统的能量及稳定性等, 并在同一方法下对结构全优化后的C36和Y@C36进行了能量、能级、态密度及光学性能分析, 研究了Y原子的嵌入对C36结构和性能的影响. 相似文献
130.