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101.
In this paper, the molecular and crystal structures of the NH4[Y(trans CYDTA)(H2O)2]·4.5 H2O(trans-CYDTA=trans 1,2-cyclohexanediaminetetraacetic acid) are reported. The crystal data are as follows: Triclinic system, P1space group,a=0.8599(6)nm,b=1.0021(7)nm,c=1.4370(9)nm,α =88.095(13)°,β =75.559(1)°,γ =88.344(12)°,V=1.1981(14)nm3,Z=2, M=708.68,Dc=1.570g· cm-3, μ =2.506mm-1 and F(000)=590. The final R1 and wR2 are 0.0571 and 0.1350 for 4205 [I >2.0σ (I)] unique reflections and 0.1007 and 0.1615 for all 4981 reflections, respectively. In the title complex, the anion [Y(trans-CYDTA)(H2O)2]- has an eight coordination structure with distorted square antiprism. The trans CYDTA which acts as a hexadentate ligand with four Oatoms and two Natoms and two H2O molecules directly coordinate to central metal Y(Ⅲ) ion. It can be known that the Y(Ⅲ) ion can form an eight coordinate compound with aminopolycarboxylic acid ligands in addition nine coordination structure.  相似文献   
102.
A new phase selective hydrocarbon soluble polymer support is described.  相似文献   
103.
Novel spherical mesoporous silica materials with uniform diameters and starburst mesopore structures were synthesized by a simple one-step procedure with ethanol as the co-solvent in dilute aqueous solution and their formation mechanism was proposed. The arrangement of the pore canal and the diameter of the sphere could be tailored by altering the concentration of ethanol.  相似文献   
104.
Gd@C82(OH)40 has been developed as a new generation of MRI contrast agent. But recently, it was found that Gd@C82(OH) x with a larger number of OH (x>36) would lead to cage break and hence, release of highly toxic Gd ions. We synthesized the more stable Gd@C82(OH) x with less OH-number, Gd@C82(OH)16, and studied its proton relaxivity and MRI images. The results indicate that Gd@C82(OH)16 also gives high proton relaxivity, even higher than that of (NMG)2-Gd-DTPA. The bio-distribution indicated that Gd@C82(OH)16 tends to be entrapped in the liver and kidney and remained in tissue for about 2 hours. The results suggest that the more stable metallofullerene derivative Gd@C82(OH)16 can be the potential candidate of the new MRI contrast agent.  相似文献   
105.
制备了以液态苏氨酸为沟道材料的四端有机场效应晶体管,观测了其随着栅极电压的不同呈现出源漏两极之间不同的电学特异现象;还观测了苏氨酸在外电场作用下,阻抗随着源漏之间电压频率变化的关系,提出一个极性液体模型解释了其导电机理。  相似文献   
106.
A new fluorescent compound based on calix[4] arene skeleton was synthesized.Its complexation ability with transition metal ions,such as Fe^3 ,Co^2 ,Ni^2 ,Cu^2 ,Zn^2 and Ag^ ,Was investigated by UV-vis and fluorescent spectra.  相似文献   
107.
机械球磨与反应烧结合成Sr2CeO4发光体的研究   总被引:10,自引:0,他引:10  
Sr2CeO4 phosphor was synthesized by mechanical milling and reactive sintering in this work. The solid state reaction of SrCO3and CeO2 (2∶1) started at about 850 ℃ and completed at 1 000 ℃ for about 4 h. Two types of formation mechanism of Sr2CeO4 were proposed. When the starting powder mixture was fired above 1 000 ℃, the unstable intermediate phase SrCeO3was developed, which then reacted with SrCO3to form the final product Sr2CeO4, however, SrCO3and CeO2 converted directly to Sr2CeO4 at a lower temperature. The XRD results showed the crystal structure of Sr2CeO4 was orthorhombic. The emission spectra displayed a broad band with maximum at about 465 nm. The mechanical milling of starting power mixture and the sintering temperature had no effect on this emission spectra.  相似文献   
108.
呋喃甲醛缩二乙撑三胺希夫碱铜配合物的合成及结构(英)   总被引:1,自引:0,他引:1  
A novel copper(Ⅱ) complex CuL(NO3)2(where L=N,N′-bis(furaldehyde)-diethylenetriamine) was synthesized and characterized by X-ray crystallography analysis. The crystal belongs to monoclinic, space group C2/c with cell parameters a=1.924 0(6) nm, b=0.792 8(3) nm, c=2.504 1(8) nm, β=111.163(5)°, and Z=8. The coordination geometry around Cu(Ⅱ) is a distorted trigonal-bipyramid,and one-dimensional chain is formed through intermolecular hydrogen bonds. CCDC: 255629.  相似文献   
109.
110.
TS分子筛催化性能研究Ⅰ.TS-2分子筛催化1,2-丙二醇液相氧化反应的研究①伏再辉尹笃林(湖南师范大学精细催化合成研究所,长沙410081)关键词TS-2分子筛1,2-丙二醇氧化催化氧化自1983年Taramasso[1]首次合成具有ZSM-5结构...  相似文献   
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