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A series of derivatives of meso-tetraphenylporphine, with neutral, acidic and basic functional groups, has been prepared. Several of these compounds were synthesized directly via the Rothemund reaction, under a variety of conditions to obtain optimal yields; others were prepared by interconversions of various functional groups. Drastic reaction conditions employed for hydrolysis, alcoholysis, or lithium aluminum hydride reduction did not affect the porphine ring system. The two amino derivatives showed anomalous spectra in the visible range.  相似文献   
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Using an asymptotic methodology we formulate a fast, accurate algorithm for the inversion of multi-phase flow data. The approach is appropriate for many common reservoir production strategies such as CO2 and water flooding. The technique compares well to a purely numerical method with a significant reduction in computation time. In an application to fractional flow data from the North Robertson field in West Texas, 100,000 permeability and porosity parameters are determined on a workstation. Generally, higher permeability, approaching 1milli-Darcy, is found in the eastern portion of the reservoir. The permeability estimates agree with type curve analysis for material and volumetric balances and a previous numerical pilot-point inversion.  相似文献   
3.
The octaethylporphyrin(OEP) complexes of iron(III) chloride, iron(III) acetate, thallium(III) hydroxide, zinc(II), and cobalt(II) and the mesoporphyrin IX dimethyl ester (MPDME) complexes of zinc(II) and iron(III) chloride were reacted with a 20:1 ratio of NO2 to metalloporphyrin in CH2Cl2. The +3 metalloporphyrins gave products which had a nitromethyl group in each of the four meso positions of the porphyrin ring and a chloride ion bound to the metal atom. The products of +2 metalloporphyrin reaction had a nitro group bound in each of the meso positions. The spectral and electrochemical properties of some of the products were measured. 36Cl labelled OEPFeCl was reacted with NO2 in CH2Cl2. The product, meso-tetranitromethyl OEPFeCl, had 17% of the original activity which indicates that the chloride ion bound to the iron is exchanged with chloride ions formed in the reaction. The nitromethylation reaction appears to involve initially the displacement of chloride from iron(III) by NO2 and solvent attack on the bound NO2. The meso-nitration of the +2 metalloporphyrin by NO2 has been proposed to proceed by a π-cation radical mechanism (E.C. Johnson and D. Dolphin, TetrahedronLetters 2197 (1976).  相似文献   
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本文报道了一种测定紫锥花草药中咖啡酸、对羟基苯甲酸、对-香豆酸、原儿茶酸、丁香酸、阿魏酸、香草酸、咖啡奎尼酸、洋蓟酸、菊苣酸和紫锥花苷等11种酚类化合物的高效液相色谱分析方法。本法可应用于各种紫锥花草药中酚类化合物的测定。结果表明,在紫锥菊种属中含量最多的酚类化合物是菊苣酸、咖啡奎尼酸和紫锥花苷;在狭叶紫锥菊种属中含量较丰的是紫锥花苷和菊苣酸;而在白花紫锥菊种属中则以紫锥花苷以含量较多。  相似文献   
5.
A complete series of five phenyl/4-benzyloxyphenyl 5,10,15,20-substituted porphyrin has been synthesized, characterized by analysis, Rf values, and proton-nmr spectroscopy (pmr). Their physicochemical properties, namely ir spectra, absorption spectra, emission spectra, excited state life-times, pK3 values, reduction potentials, and kinetics of Cu(+2) insertion, have been determined. Attempts have been made to correlate these physicochemical properties with the structures of the porphyrins.  相似文献   
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