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Evaluation of the Residual Capacity of Structure in PBSD Through Seismic Hazard Analysis
Establishting the Relationship between Damage Measure, Seismic Hazard, Structural Ductility and Period for PBSD
(3(3):7-13)A Study of Tannin in the Pericarp of Longan
Longan (Nephelium longana, Camb) is a native fruit tree in south China. The pulp is edible, while the pericarps were thrown away as rubbish, the quantity of which is considerable. In order to utilize this wasted part, the writer made an analysis of the pericarp and found that it contains tannin which may be used for tanning leather. Turther study was made on the properties of tannin contained in it. The study consists of following two steps:-
Ⅰ. Extracting and analyzing of the tannin of the pericarp of Longan.
Ⅱ. Refining of the tannin extracted from the pericarp of Longan.
The experimental results are summarized as follows:
1. The optimum temperature for extracting tannin from the pericarp should be 80℃.
2. The duration of soaking is considered to be most favorable between 30-60min.
3. Since the tannin thus extracted from the pericarp is thermo-unstable, lower temperature must be used during condensing procedure.
4. The extract solution showed comparatively high Non-tannin contents low degree of purity, it can be, therefor, used for head liquor tannin to save shrinkage.
5. To avoid any chemical change of tannin, which may result a loss of tannin, the duration of condensing procedure should be shortened as much as possible.
6. The best result has been obtained when a vacuum condenser is used for condensing the extracted solution
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