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松香中海松酸型树脂酸在酸作用下的组成变化规律 被引量:8
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作者 陈玉湘 赵振东 +4 位作者 古研 王玉民 李冬梅 毕良武 王婧 《精细化工》 EI CAS CSCD 北大核心 2009年第8期818-823,共6页
详细研究了在溶液状态下酸催化作用引起松香中海松酸型树脂酸组成变化的特征及规律,以甲苯、醋酸等作为溶剂,醋酸、盐酸、硫酸等作为催化剂,反应温度为保持良好回流,反应时间1~8h。研究结果表明,松香中的海松酸型树脂酸在醋酸作用下比... 详细研究了在溶液状态下酸催化作用引起松香中海松酸型树脂酸组成变化的特征及规律,以甲苯、醋酸等作为溶剂,醋酸、盐酸、硫酸等作为催化剂,反应温度为保持良好回流,反应时间1~8h。研究结果表明,松香中的海松酸型树脂酸在醋酸作用下比较稳定,其组成没有发生明显的变化。在盐酸、硫酸作用下,松香中原有的海松酸、异海松酸、山达海松酸明显减少,初始质量分数越高、酸作用时间越长,减少越明显,与此同时产生了原料中没有的8,15-异海松酸、8,15-海松酸和7,15-海松酸,且随酸作用时间延长而增多。在质量分数为51.4%的硫酸催化作用下于甲苯中回流8h后,湿地松松香中的海松酸型树脂酸质量分数变化为:异海松酸由13.77%降至10.53%,山达海松酸由1.78%升至1.98%,8,15-异海松酸则从0升至5.05%;马尾松松香中的海松酸型树脂酸质量分数变化为:海松酸由7.45%降至3.02%,7,15-海松酸由0升至0.67%,8,15-海松酸则从0升至3.99%。海松酸型树脂酸主要发生以环内双键位置变化为主的异构反应,很少发生分解反应,而环外乙烯基则没有参与反应,松香中各海松酸型树脂酸总质量分数基本不变。对海松酸型树脂酸各成分的立体结构分析及异构体之间的相关性分析结果表明,8,15-异海松酸应来源于异海松酸和山达海松酸的异构化,而8,15-海松酸和7,15-海松酸应来源于海松酸的异构化反应。 展开更多
关键词 松香 海松酸型树脂酸 酸处理 组成变化关系 异构化 精细化工中间体
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Seasonal variation in fatty acid composition of seston and the copepod Calanus sinicus(Brodsky,1962)in Jiaozhou Bay and its trophic implications 被引量:5
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作者 刘梦坛 李超伦 孙松 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第6期1164-1173,共10页
The fatty acid compositions of seston and Calanus sinicus were investigated to study trophic relationships in Jiaozhou Bay. Principal component analysis was carried out to ordinate the fatty acid patterns of seston in... The fatty acid compositions of seston and Calanus sinicus were investigated to study trophic relationships in Jiaozhou Bay. Principal component analysis was carried out to ordinate the fatty acid patterns of seston in stations and months. The results showed that diatoms were most abundant in the phytoplankton at station A5 (located in the northwest of the bay: 36~9'N, 120~20'E) and least abundant at station D7 (located outside of the bay: 35~59'N, 120~26'E). By contrast, dinoflagellates were most abundant at station D7 and least abundant at station A5. According to the annual variations of 16:1 (o7 and 18:4(o3/ 16:1(o7, diatoms flourished mainly in spring and summer, while dinoflagellates bloomed exclusively in summer. A distinctive feature of the fatty acid composition of C. sinicus was the prevalence of 20:5o3 and 22:6(o3. The higher content of 16:1(o7 over 18:4(o3 in females indicated that diatoms contributed more than dinoflagellates to the diet of C. sinicus. The feeding intensity of C. sinicus on diatoms was higher in spring and autumn than in other seasons. The herbivorous indicators 20:1 and 22:1 were comparatively low, suggesting that besides phytoplankton, C. sinicus might feed on a wider range of particles including organic detritus, bacteria and small copepods. 展开更多
关键词 fatty acid SESTON Calanus sinicus trophic relationships
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