英语科技论文摘要写作.pptVIP

Descriptive abstract 1. Tell readers what information the report, article, or paper contains; 2. Include the purpose, methods, and scope of the report, article, or paper; 3. Do not provide results, conclusions, or recommendations; 4. Are always very short, usually under 50 words; 5. Introduce the subject to readers, who must then read the report, article, or paper to find out the author’s results, conclusions, or recommendations. Informative Abstract Communicate specific information from the report, article, or paper; Include the purpose, methods, and scope of the report, article, or paper; Provide the report, article, or paper’s results, conclusions, and recommendations; Are short. Usually informative abstract are 10% or less of the length of the original piece; Allow readers to decide whether they want to read the report, article, or paper. Sample 2 Field experience with several industrial reciprocating plate liquid-liquid extraction columns indicated that large density gradients in the continuous phase resulted in excessive backmixing. Since there are no published data on the effect of higher density in the upper section compared to lower density in the bottom section of the column, experiments were performed with the calcium chloride brine-water system in a 76.2 mm diameter reciprocating plate column. Axial dispersion coefficients, E, were found to be 10-20 times higher than the values in systems with uniform densities. E decreased with increasing agitation to 30% of the value with no agitation. The effect of increasing flow rate of water up the column was to increase both E and the Peclet number. E was correlated with the density difference between any point in the column and tap water. Another correlation was obtained showing the effects of buoyant and mechanical energy input on axial dispersion measurements of catalyst diffusivity and reactor heat transfer using a one-dimensional heterogeneous reactor model. Model predictions and observed