• 설비공학논문집
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• 제13권1호
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• pp.25-29
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• 2001

A study has been conducted to investigate the effect of the heat transfer surface position in the range of dropwise condensation, filmwise condensation, and glacial condensation. For dropwise condensation promoter, the heat transfer surface was evaporated by gold. As a result, heat transfer rate is almost same where the position of heat transfer surface is between 45 and 135 degree. It is found that heat transfer rate was reduced as subcooled degree was increased. And it is also found that if the subcooled degree becomes lower, the position of heat transfer surface is more effective. Adversely, if the subcooled degree becomes higher, the effectiveness of surface position is getting relatively lower. Regardless of the position, the transition temperatures from dropwise condensation to filmwise condensation is in the vicinity of 80K.

• Archives of Pharmacal Research
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• 제15권1호
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• pp.1-4
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• 1992

4-Acetylantipyrine 1 underwent condensation with 4-formyl-antipyrine 2 to give 3. Condensation of either 3 with 1 or 1 with 2 in a molar ratio of (2 :1) afforded 4. Cyclization of 4 in the presence of PPA and ammonium acetate or 4-aminoantipyrine in the presence of glacial acetic acid gave 5-6 respectively. Claisen condensation of 1 with ethyl acetate and diethyl oxalate afforded compounds 8-10. The reaction of 1 and 2 with indole in ethanol/conc. hyddrochloric acid was also investigated.

• Bulletin of the Korean Chemical Society
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• 제30권4호
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• pp.797-802
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• 2009

Potential of acetates and related compounds in glacial acetic acid as a catalyst for aldol-type condensation reactions was examined. Reactions of cycloalkanones or selected heteroaromatics with aldehydes in presence of 10 mol% of various acetates in acetic acid afforded ${\alpha},{\alpha}$'-bis(substituted-benzylidene)cycloalkanones and substituted-benzylidene-mackinazolinones, respectively, in good yields. Among the compounds tested, ammonium acetate is the best and effective especially towards the reactions of mackinazolinone and aliphatic aldehydes to afford 6-alkylidenemackinazolinones.