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豫让金虫 (正式写手)
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[求助]
求助！萃取方面的
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A preliminary study of resveratrol transfer was made in five organic solvents: pentan-1-ol, pentan-2-ol, 4-methylpentan-2-ol, cyclohexane, and chloroform. For these experiments, the solution mass was msol = 18 g and solvent mass, msolv = 32 g, so the weight ratio was 36%. The resveratrol mass in 18 g of wine concentrate was 0.78 mg (mRinit). The results of material balances, selectivities and yields are summarized in Table 1. For the solvents pentan-1-ol, pentan-2-ol, and 4-methylpentan- 2-ol, a total transfer of resveratrol was observed, resulting in a high extraction yield. The selectivities, however, were different: the mass of organic solids mESorg was lower when pentan-1-ol was used, hence selectivity was greater. For cyclohexane, no transfer occurred (the solvent remained colorless); the mass of organic solids was zero. For chloroform, some solutes of the solution were transferred but not resveratrol. This solvent can be used in the prewash solution to reduce the amount of impurities and thus improve extraction selectivity. Taking into account these results and especially the fact that alcohols were efficient extraction solvents, a selective transfer was considered with a mixture of organic solvents. Cyclohexane/ alcohol was tested as extraction solvent; cyclohexane to limit the transfer of other solutes, alcohol to promote that of resveratrol. |
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alvarohao
铁杆木虫 (著名写手)
- 翻译EPI: 85
- 应助: 0 (幼儿园)
- 贵宾: 0.005
- 金币: 13664.2
- 红花: 3
- 沙发: 5
- 帖子: 2355
- 在线: 261.5小时
- 虫号: 1402388
- 注册: 2011-09-15
- 性别: MM
- 专业: 机械结构强度学
【答案】应助回帖
★ ★ ★ ★ ★ ★
豫让(金币+10, 翻译EPI+1): 2011-11-26 20:59:52
爱与雨下(金币+1): 2011-11-27 08:41:57
爱与雨下(金币+5): bb代发 2011-12-06 08:53:03
豫让(金币+10, 翻译EPI+1): 2011-11-26 20:59:52
爱与雨下(金币+1): 2011-11-27 08:41:57
爱与雨下(金币+5): bb代发 2011-12-06 08:53:03
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白藜芦醇转移的初步研究是在五种有机溶剂中进行的：戊烷-1-乙醇，戊烷-2-乙醇，4-甲基戊-2-乙醇，环己烷以及氯仿。在这些实验当中，欲分离之溶液的质量为msol=18g，溶剂质量为msolv=32g，因此质量比率为36%。18g浓缩葡萄酒中含0.78mg的白藜芦醇。表1总结了物料平衡，分离性以及产量。 对于溶剂戊烷-1-乙醇，戊烷-2-乙醇，4-甲基戊-2-乙醇，所有的白藜芦醇都转移完全，萃取产量很高。但是分离性则有所不同：当使用烷-1-乙醇时，有机固体的质量mESorg降低，分离性更高。对于环己烷，则没有发生转移（溶剂仍然为无色）。有机固体的质量为零。对于氯仿，溶液的某些溶质发生了转移，但不是白藜芦醇。此溶剂可作为预洗溶剂来减少杂质的含量以便提高萃取的分离性。 考虑到这些结果以及乙醇作为有效的萃取溶剂的事实，使用一种有机溶剂混合物作为萃取溶剂以提高转移的分离性。环己烷/乙醇经过测试可以作为这样的萃取溶剂；环己烷限制其它溶质的转移，乙醇则用来提高白藜芦醇的产量。 |
2楼2011-11-26 19:06:03
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