赵莉,张阳,陈晨,陆强,董长青.羟基和甲氧基对木质素Cβ—O键均裂的影响[J].农业机械学报,2015,46(2):181-186.
Zhao Li,Zhang Yang,Chen Chen,Lu Qiang,Dong Changqing.Effects of Hydroxyl and Methoxyl Groups on Homolysis of Cβ—O Bond in Lignin Model Compounds[J].Transactions of the Chinese Society for Agricultural Machinery,2015,46(2):181-186.
摘要点击次数: 3182
全文下载次数: 1471
羟基和甲氧基对木质素Cβ—O键均裂的影响   [下载全文]
Effects of Hydroxyl and Methoxyl Groups on Homolysis of Cβ—O Bond in Lignin Model Compounds   [Download Pdf][in English]
投稿时间:2014-02-26  
DOI:10.6041/j.issn.1000-1298.2015.02.027
中文关键词:  木质素 模型化合物 均裂 解离能
基金项目:国家高技术研究发展计划(863计划)资助项目(2012AA051803)和国家自然科学基金资助项目(51276062)
作者单位
赵莉 华北电力大学 
张阳 华北电力大学 
陈晨 华北电力大学 
陆强 华北电力大学 
董长青 华北电力大学 
中文摘要:利用密度泛函理论(DFT)方法计算了18种β—O—4连接的木质素模型化合物的Cβ—O键均裂解离能,讨论了模型化合物上不同位置羟基和甲氧基对解离能的影响,探究了取代基之间的交互作用。结果表明,Cα位羟基对解离能影响小。在R3位无甲氧基时,增加的Cγ位羟基对解离能影响较小;然而在R3位有甲氧基时,增加的Cγ位羟基氢与甲氧基氧之间形成氢键,显著增加醚键解离能。R3和R4位甲氧基均降低解离能,在Cγ位无羟基时,R3位甲氧基对解离能的降低作用最为显著;在Cγ位有羟基时,受Cγ位羟基与R3位甲氧基形成的氢键对醚键的稳定作用影响,R3位甲氧基对解离能的降低作用被弱化。R4位甲氧基不受Cγ位羟基的影响,对解离能的降低程度稳定。R1、R2位甲氧基对解离能影响较小也无特定规律,并且不与其他位置取代基产生交互作用。
Zhao Li  Zhang Yang  Chen Chen  Lu Qiang  Dong Changqing
North China Electric Power University,North China Electric Power University,North China Electric Power University,North China Electric Power University and North China Electric Power University
Key Words:Lignin Model compound Homolysis Bond dissociation energy
Abstract:The substituted groups in lignin can influence the pyrolysis characteristics. Density functional theory (DFT) was employed to calculate the bond dissociation energies (BDEs) of the Cβ—O bonds in 18 lignin model compounds with β—O—4 linkages. The model compounds were grouped and compared to discuss the effects of hydroxyl and methoxyl groups at different positions on the BDEs. The interactions between different groups were also studied. The results indicated that there was minor influence of the hydroxyl group at Cα. The hydroxyl group at Cγ hardly affected the BDE when there was no methoxyl group at R3. However, when there was methoxyl group at R3, hydrogen bond would be formed between the hydroxyl group at Cγ and the methoxyl group at R2, and thus the spatial structure of the model compound would be strengthened and the BDE was increased. The methoxyl groups at R3 and R4 can reduce the BDEs. The methoxyl group at R3 can obviously reduce the BDEs when there was no hydroxyl group at Cγ. However, the reducing effect was weakened when there was hydroxyl group at Cγ, because the hydrogen bond between the methoxyl group at R3 and hydroxyl group at Cγ would strengthen the ether bond. The methoxyl group at R4 was not influenced by the hydroxyl group at Cγ, and thus the reducing effect on the BDE was stable. The methoxyl group at R1 and R2 had minor effects on the BDE, and moreover, it did not participate in the interactions with other functional groups.

Transactions of the Chinese Society for Agriculture Machinery (CSAM), in charged of China Association for Science and Technology (CAST), sponsored by CSAM and Chinese Academy of Agricultural Mechanization Science(CAAMS), started publication in 1957. It is the earliest interdisciplinary journal in Chinese which combines agricultural and engineering. It always closely grasps the development direction of agriculture engineering disciplines and the published papers represent the highest academic level of agriculture engineering in China. Currently, nearly 8,000 papers have been already published. There are around 3,000 papers contributed to the journal each year, but only around 600 of them will be accepted. Transactions of CSAM focuses on a wide range of agricultural machinery, irrigation, electronics, robotics, agro-products engineering, biological energy, agricultural structures and environment and more. Subjects in Transactions of the CSAM have been embodied by many internationally well-known index systems, such as: EI Compendex, CA, CSA, etc.

   下载PDF阅读器