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71.
The space group of [(H2O)(C3H4N2)(O2CCH=CHCO2Zn)]n, which was originally described in the acentric Pc space group (Liu et al., Chin. J. Struct. Chem 2004, 23, 160~163),is re-described in the centric P21/c space group.  相似文献   
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This paper reports the study on the polymer protected catalyst CPVC-FeCl3 used in esterification,transesterification,synthesis of acetals or ketals and rearrangement reaction of pinacol.The catalyst has the advantages of being simple in operation,non-corrosive,easy to separate from mixtures and good reusability.  相似文献   
74.
The reactivity ratios of the trinary system of triallyl isocyanurate,divinylbenzene and vinyl acetate wrere calculated from the Q and e values determined by other investigators.According to these ratios,the terpolymerization of these monomers was predicted possible and the polymerization was carried out by suspension polymerization with toluene and gasoline as extenders,forming spherical macroporous terpolymers.The influences of the amount of the extenders and the crosslinking degree on the pore propertities were studied.The result showed that under adequate reaction conditions,this polymerization system could produce macroporous copolymers with very high surface area(>1000m^2/g) which have never been obtained in other polymerization system using silimar polymerization technique.This was most probably caused by the formation of some linear or branched poly(vinyl acetate) during the polymerization process because of the poor copolymerizing ability of vinyl acetate.This linear or branched polymer acted as an extender and formed a trinary pore porducing reagent with toluene and gasoline.  相似文献   
75.
<正> Crystal and molecujar structure of the title compound, C29H19NO3, was determined by single crystal X-ray diffraction analysis. .Mt=429. 48, monoclin-ic, space group P21/n, a = 10. 365 (3), b= 14. 614(4), c= 14. 857 (4) A ,β= 103.55(2)°,V=2186. 1(10) A3, Z=4, Dc= 1. 30g/cm3,μ(MoKa) = 0. 81cm-1, F (000) = 919. 87. Final residual R value was 0. 0704 and Rw = 0. 0704. The indo-hzine ring is conjugated only with the 1-benzonyl group.  相似文献   
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The sorption behavior of N-methyl-2-thio-imidazole resin(MTIR) for Rh(Ⅲ) was investigated.The optmum sorption condition of MTIR for Rh(Ⅲ),sorption rate t1/2=84min,sorption capacity 1.37mmol Rh(Ⅲ)/g MTIR,[140.5mg Rh(Ⅲ)/g MTIR],sorption molar ratio 0.34Rh(Ⅲ)/functional group,distribution coefficient D=2.5&#215;10^3mg&#183;g^-1 were determined.The sorption selectivity of MTIR for Rh(Ⅲ)in the presence of common metal ions,Fe^3+,Co^2+,Ni^2+ and Cu^2+ was examined.Rh(Ⅲ) adsorbed on MTIR can be eluted quantitatively by using a mixed solution composed of 20% thio-urea-acetone:6mol HCl.dm^-3(1:1vol.) used as an eluent.Rh(Ⅲ) can be separated from the mixture of Rh(Ⅲ) and Fe^3+,Co^2+,Ni^2+,Cu^2+ by using D72 resin and MTIR successively.  相似文献   
78.
In this paper,we have studied the adsorption properties of gold by α-alkyl substituted pyridine resin( BPR) in alkaline solution.The single and dual component kinetic mass transfer process of Au(I),Ag(I) and other metal cyanide ions were also investigated.The results obtained show that the mass transfer rates of the cyanide ions in the resin phase are closely related to the molar ratio and the configuration of metal cyanide ions. The elution kinetics of Au(I) and other cyanide ions by NH4SCN has been investigated systematically.The intraparticle diffusion coefficient and activation energy of Au(I),Ag(I),Ni(I) Fe(Ⅲ) cyanide anions were determined in CI,NO3,OH-type BPR resin at different temperatures.It is found from the experimental results that the mechanism for extracting Au(I),Ag(I) and other metal cyanide anions by BPR resin belongs to ion exchange process.The difference of activation entropy of some metal cyanide anions(ΔS-ΔS^-) was evaluated.  相似文献   
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