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31.
32.
在一定研究基础上合成出分子式为{Ag~2(hpb)(ClO~4)~2[(CH~3)~2CO]~2}1(hpb=C~6Ph~6)的二核银配合物,并制备出自由配体hpb的单晶2,其结构由X射线单晶衍射表征。将这两种化合物与先前研究结果比较发现,配合物的分子空间结构不仅依赖于阴离子大小、溶剂性质,还取决于溶剂类型和自由配体的分子空间结构与排列,并且这种结构变化导致了导电性的不同。  相似文献   
33.
The 2D porous copper(Ⅰ) complex with 1,3-dicyanobenzene (DCB), [Cu(DCB)2](PF6)(Me2CO) 1, exhibits channels along axis c, in which one molecule acetone and one anion PF6 per formula unit are included respectively. The reversible incorporation of guest acetone and acetonitrile, as well as the anion exchange from PF6^- to BF4^- or CF3SO3^-, was investigated by thermogravimetric (TG) analysis, ^1H NMR spectra and/or infrared absorption spectroscopy. Additionally, the incorporation of benzene and toluene into complex 1 was also discussed. Complex 1 exhibited size selectivity for guest inclusion or anion exchange.  相似文献   
34.
Hydrogen production by conversion of methane over Ni-supported zeolite catalysts was investigated, and Ni-supported USY-type zeolite (Si/Al2 = 14.0, 360) was found to have longer catalytic lifetime than Ni-supported silica (Cab-O-Sil) catalyst, which had been reported to have the longest catalytic lifetime for this reaction.  相似文献   
35.
The chiral separation of loxoprofen was achieved on a chiral column with UV and circular dichroism (CD) detection. The good resolution of four loxoprofen stereoisomers was obtained. The column used for the chiral separation was Chiralcel OJ column (250 x 4.6 mm) using hexane-2-propanol-trifluoroacetic acid (95:5:0.1), as an eluent. The flow-rate was 1.0 ml/min and the detection was at 225 nm. In addition, CD and UV spectra were obtained by stopped flow scanning. The method allows the determination of the stereoisomers of loxoprofen in human plasma after the administration of therapeutic dose of the racemic drug, thus HPLC with CD detector is useful for the stereospecific determination of loxoprofen products in biological samples.  相似文献   
36.
A new coluster-cracking method to synthesize dithiolate metal complexes was reported and four unsymmetric complexes with formula(Me4N)2[M(Ln)(SPh)2](M=Cd and Zn,L1=dmit=1,3-dithiole-2-thione4-5,dithiolate,L2=dmid=1,3-dithiole-2-one-4,5-dithiolate,SPh=thiophenolate)(1-4)were characterized by elemental analysis,IR,UV NMR spectra and so on.The advantages of this method are summarized in two aspects:(1) the preparation is very convenient;(2) the reaction usually completed giving the product with high pruity.The crystal structure of 1 showed that the bond distances of Cd(Ⅱ)to the sulfur of the thiophenolate group are shorter than those of Cd(Ⅱ)to the sulfur of dmit,so that the thiophenolate group does not be replaced in the reaction and thmixed ligand complexes are the dominant produxts.The dmit complexes showed well third-order NLO properties,but not of the dmid complexes,although dmid is an analogue to dmit.  相似文献   
37.
Fischer-Tropsch syntheses (FTS) were carried out in a slurry phase over Ru/Al2O3 catalysts using hexadecane as a solvent. The outcome of the FTS was dependent on the oxide support, calcination temperature, synthesis gas composition and sulfur content. The addition of Mn/Na to Ru/Al2O3 was effective in raising the initial activity and C5+ selectivity, but after 20 hours, the performance of the modified catalyst was similar to that of the unmodified catalyst. An additional investigation involving the use of fresh vs used catalysts demonstrated that an agglomeration of the metallic Ru, at least in part, does occur during the reaction.  相似文献   
38.
Reaction of [2.2]paracyclophane with silver(I) heptafluorobutyrate (AgC3F7CO2) has isolated three novel networks: [Ag4(pcp)(C3F7CO2)4] x pyrene (1), [Ag4(pcp)(C3F7CO2)4] x phen (phen = phenanthrene) (2), and [Ag4(pcp)(C3F7CO2)4] x fluorene (3), and an intercalation compound [Ag4(pcp)(C3F7CO2)4] x 2benzene (4). All the four complexes exhibit two-dimensional (2D) sheet structures in which AgC3F7CO2 form an infinite chain and pcp acts as linkage. 1, 2, and 3 show 2D flat sheets with cavities in which guest molecules are situated, whereas 4 exhibits 2D zigzag layers between which guest benzene molecules are intercalated. Pcp shows mu-di-eta1-eta2 coordination mode in 1, mu-tetra-eta1 coordination mode in 2 and 3, and mu-tetra-eta2 coordination mode in 4. The reversible guest exchanges were observed between complex 1, 2, or 3 and intercalation compound 4. It is unprecedented for metal-organic inclusion complexes that the guest exchange occurs where the guest is the solute molecule. Furthermore, 4 can release the guest, and the original framework was completely recovered after reincorporation of benzene. It should be noted that 4 can incorporate pyrene, phen, and fluorene to give 1, 2, and 3, respectively, after desorption.  相似文献   
39.
The title one‐dimensional chain polymer complex, [Mn(C6H4NO3)Cl(C6H5N)2]n, was isolated from the reaction of MnCl2 with 6‐oxo‐1,6‐dihydro­pyridine‐2‐carboxylic acid (HpicOH) in pyridine. The asymmetric unit contains one [Mn(HPicO)Cl(py)2] moiety (py is pyridine), with the (HpicO) ligand acting in a tridentate manner via the two carboxyl­ate O atoms and the pyridone O atom. The operation of inversion centres generates eight‐ and 14‐membered rings and, in conjunction with an a‐axis translation, leads to an infinite chain extending along [100]. The Mn⋯Mn separations in this chain are 5.1069 (6) and 7.1869 (6) Å. The MnII atom has a distorted octahedral coordination, with trans‐axial pyridine ligands and with three O atoms and the Cl atom in the equatorial plane. The conformation of the 14‐membered ring is stabilized by pairs of inversion‐related N—H⋯O hydrogen bonds.  相似文献   
40.
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