乙酰纤维素

After acetylation of cellulose, the allomorph of CTA changed and the crystallinity decreased; however, amorphism is dominant in CDA obtained by hydrolysis from CTA and spinning resulted in the reduction of crystallinity in CDA.

纤维素乙酰化后形成CTA，其晶型发生变化，结晶度降低；而CTA水解后得到的CDA，无定形占明显优势，纺丝过程中的取向又会进一步降低CDA的结晶度。

Insects polysaccharide from insect crust are a natural macromolecular polymers that remove behind the acetyl group getting usually that paries draw, which are currently found only bring positive charge of the animals cellulose in the natural world- containing amino polysaccharide of high-molecular compound.

昆虫多糖是从昆虫体壁提取的甲壳素脱去乙酰基后得到的一种天然高分子聚合物，也是目前发现的自然界中唯一带正电荷的可食性动物纤维素——含氨基多糖的高分子化合物。

In this paper the study on optimizing the esterification of cellulose and some character of CAB(the degree of substitution of cellulose, solubility, the thermal properties and molecular weight) was discussed. The mechanism of the esterification of cellulose in butyric acid/ acetic acid/ butyric anhydride which comprises the creation of the acetic butyric anhydride, acetyl cation and butyryl cation was investigated by the study of the effect of the content of the organic acid and anhydride on the degree of acetyl and butyryl substitution of cellulose.

最后本文根据纤维素在丁酸/乙酸/丁酸酐中的酯化反应中有机酸以及酸酐的添加量对最后产物纤维素醋酸丁酸酯中乙酯或者丁酯取代度的影响，提出纤维素在丁酸/乙酸/丁酸酐中的酯化反应经历一个混和酸酐以及乙酰碳正离子、丁酰碳正离子的生成过程。

Use tertiary system method to screen and optimize JLNCAO substrate, and use heat and dry under atmospheric pressure method, ignition residue method, The Casparian law of trace nitrogen, acid...

运用三级系统筛选法对菌草培养基进行筛选优化；用常压加热干燥法、灼烧法、微量凯氏定氮法、酸性洗涤剂法、氨基酸自动分析仪、原子荧光光谱和原子吸收光谱、乙酰丙酮法和热水提取多糖法分别对菌草香菇和木屑香菇的水分、灰分、蛋白质、纤维素、氨基酸、重金属、甲醛、香菇水溶性多糖等的含量进行比较研究。

Levulinic acid was prepared by solid SO4(superscript 2-)/Al2O3-TiO2 catalyst from cellulose in water.

以纤维素为原料，固体SO4(上标 2-)/Al2O3-TiO2为催化剂，以水为溶剂制备乙酰丙酸。

In this work, the degradation process, mechanism, kinetics as well as the separation and purification of levulinic acid production from biomass, such as wheat straw and wood powder, were evaluated at high temperature and catalyzed by acid.

本文以麦秸和木屑等木质纤维素类的可再生资源为原料，对在高温及酸存在的条件下降解制备乙酰丙酸的工艺条件、生成机理、反应动力学及提取工艺进行了研究。

A verification experiment was performed and the productivity of levulinic acid was 19.86%, which is almost the same as the model prediction.

通过验证实验，在上述优化条件下乙酰丙酸产率达到了19.86％，与模型预测值19.75％十分吻合，原料中纤维素的利用率达到68.8％。

Levulinic acid was prepared by solid SO42－/Al2O3-TiO2 catalyst from cellulose in water.

以纤维素为原料，固体SO42－/ Al2O3-TiO2为催化剂，以水为溶剂制备乙酰丙酸。

Cellulose benzoate,the degree of substitution of which was calculated from the content of C determined by element analysis,was prepared from microcrystalline celluloseand benzoyl chloride under heterogeneous condition and characterized by FT-IR and~1H-NMR.

研究了微晶纤维素和苯甲酰氯在多相条件下合成制备纤维素苯甲酸酯的反应，通过元素分析所得碳的质量百分含量计算了产物的取代度，并系统研究了吡啶与N，N-二甲基乙酰胺或与三乙胺混合反应溶剂、苯甲酰氯与纤维素羟基的摩尔比r、反应温度和反应时间对D S的影响，用FT-IR和1H-NM R对产物进行了表征。

The hydrolysis of glycosidic linkages in hemicelluloses and the b-O-4 ether bonds in lignin are catalysed by acetic acid formed at high temperature from acetyl groups present in hemicelluloses.

水解糖苷联系，在半纤维素和波- 4甲醚债券木质素是催化乙酸形成于高温，从乙酰集团目前在半纤维素。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。