Coal has a highly complex chemical structure,similar to polymers,coal is a macromolecular structure composed of a large number of“similar compounds”,which is called the basic structural unit.Understanding coal struc...Coal has a highly complex chemical structure,similar to polymers,coal is a macromolecular structure composed of a large number of“similar compounds”,which is called the basic structural unit.Understanding coal structure is the basis of its transformation and utilization.Shendong(SD)coal was analyzed by FTIR,XRD,XPS,and NMR.The results show that SD coal normalized structure formula is C_(100)H_(68.5)O_(35.7)N_(1.2)S_(0.2)and the average number of aromatic rings is 1.98.-CH_(2)-content accounts for about 82%in aliphatic CeH region,and the ratio of ether bond CeO,aromatic ether C-O and C=O is about 2:1:11 in oxygen-containing functional group region.The d_(002),L_(C),L_(a)and N_(C)of S_(D)coal microcrystalline structure parameters are 0.1832 nm,1.4688 nm,2.0852 nm and 9.017,respectively.Aromatic carbon and aliphatic carbon ratios of SD coal are 55.67%and 29.97%,aromatic cluster size and average methylene chain length are 0.224 and 1.817.Based on these structural parameters,molecular model of SD coal was constructed with^(13)C SSNMR experimental spectra as a reference.The model was constructed with an atom composition of C_(214)H_(214)O_(49)N_(2)S.展开更多
为了阐明裸子植物中纤维素与木素之间的连接方式,从多糖的角度分析糖单元与木素苯丙烷结构单元之间的共价键连接方式,合成了带6-13 C标记的纤维素前驱物尿苷二磷酸葡萄糖,并将其与PAL酶的抑制剂AOPP及外源性木素前驱物松柏醇-β-D-葡萄...为了阐明裸子植物中纤维素与木素之间的连接方式,从多糖的角度分析糖单元与木素苯丙烷结构单元之间的共价键连接方式,合成了带6-13 C标记的纤维素前驱物尿苷二磷酸葡萄糖,并将其与PAL酶的抑制剂AOPP及外源性木素前驱物松柏醇-β-D-葡萄糖苷一起投入生长中的银杏植物体内。碳13丰度检测得知纤维素在细胞壁的沉积主要是从在初生壁开始,高分辨率固体核磁13 C NMR分析证实了纤维素6位碳与木素以苯甲醚键等方式连接。展开更多
基金financed by the Department of education of Gansu Province:Young Doctor Fund Project(2022QB-029)the Fundamental Research Funds for the Central Universities(31920240125-06,31920240059)+1 种基金the Scientific Research Project of Introducing Talents of Northwest Minzu University(xbmuyjrc202215,xbmuyjrc202216)the National Natural Science Foundation of China(22178289).
文摘Coal has a highly complex chemical structure,similar to polymers,coal is a macromolecular structure composed of a large number of“similar compounds”,which is called the basic structural unit.Understanding coal structure is the basis of its transformation and utilization.Shendong(SD)coal was analyzed by FTIR,XRD,XPS,and NMR.The results show that SD coal normalized structure formula is C_(100)H_(68.5)O_(35.7)N_(1.2)S_(0.2)and the average number of aromatic rings is 1.98.-CH_(2)-content accounts for about 82%in aliphatic CeH region,and the ratio of ether bond CeO,aromatic ether C-O and C=O is about 2:1:11 in oxygen-containing functional group region.The d_(002),L_(C),L_(a)and N_(C)of S_(D)coal microcrystalline structure parameters are 0.1832 nm,1.4688 nm,2.0852 nm and 9.017,respectively.Aromatic carbon and aliphatic carbon ratios of SD coal are 55.67%and 29.97%,aromatic cluster size and average methylene chain length are 0.224 and 1.817.Based on these structural parameters,molecular model of SD coal was constructed with^(13)C SSNMR experimental spectra as a reference.The model was constructed with an atom composition of C_(214)H_(214)O_(49)N_(2)S.
文摘为了阐明裸子植物中纤维素与木素之间的连接方式,从多糖的角度分析糖单元与木素苯丙烷结构单元之间的共价键连接方式,合成了带6-13 C标记的纤维素前驱物尿苷二磷酸葡萄糖,并将其与PAL酶的抑制剂AOPP及外源性木素前驱物松柏醇-β-D-葡萄糖苷一起投入生长中的银杏植物体内。碳13丰度检测得知纤维素在细胞壁的沉积主要是从在初生壁开始,高分辨率固体核磁13 C NMR分析证实了纤维素6位碳与木素以苯甲醚键等方式连接。