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茚和茚满衍生物及其在医药工业中的应用 总被引:1,自引:0,他引:1
目前茚的生产路线有二种路线。一种是从煤焦油中分离出来的方法。但是在煤焦油蒸馏镏分中,除茚外还含有难分离的苯甲晴和丁苯和苯酚等杂质。因此要得到高纯度的茚比较困难。另外从该路线的方法要得到茚满困难。一般将茚反过来进行加氢还原的方法才能得到茚满。 相似文献
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Douglas W. McKee 《Fuel》1983,62(2):170-175
The catalytic effects of alkali metal salts in the gasification of carbonaceous materials by oxygen, steam and carbon dioxide are described. The most effective catalysts are generally the carbonates, oxides and hydroxides; other active salts tend to convert to these species under gasification conditions. Current theories of the mechanism of this type of catalysis are reviewed. Thermodynamic considerations, the results of thermal analysis and the magnitude of kinetic isotope effects suggest that cyclic sequences of elementary reactions are responsible for the catalytic phenomena. 相似文献
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A study has been made of the gasification behaviour, in carbon dioxide and steam, of a number of coal chars doped with small amounts of alkali metal carbonates. For a given additive, the magnitude of the catalytic effect increased with the rank of the parent coal. A progressive loss in catalytic activity on thermal cycling during steam gasification was associated with reaction of the alkali salts with mineral matter in the chars. The kinetic data were consistent with catalytic mechanisms involving oxidation/reduction cycles on the char substrates. 相似文献
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Polycrystalline (PbS)1.14(TaS2)2, a misfit layer sulfide, was used as cathodic material for lithium secondary battery. One molar LiClO4 in propylene carbonate (PC) was used as electrolyte. The cell could be galvanostatic discharged down to x = 4.6 [Lix(PbS)1.14(TaS2)2] when the current density was 65 μA cm−2 and the cell was cycled more than 100 times between 3.5 and 1.5 V at a current density of 260 μA cm−2. Lattice expansion increased linearly with lithium content and was less than that reported for the Li/TaS2 system. Chemical diffusion coefficients were determined by a modified version of the galvanostatic intermittent titration technique and they were fairly constant in the composition range 0.2 < x < 1, and an average value of 8.1 × 10−11 cm2 s−1 was calculated. Sodium intercalation was also accomplished, but the uptake of this ion resulting in a significant lattice expansion compared with that observed for lithium ions. Moreover, a similar dependence of the sodium chemical diffusion coefficient on the composition was observed with an average value of 1.4 × 10−10 cm2 s−1, somewhat higher than that of lithium ion. We believe that differences in lattice expansion may be responsible for the differences found in the chemical diffusivity values. 相似文献
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