1) degree of substitution
取代度
1.
Research on preparation of carboxymethyl starch with high degree of substitution;
高取代度羧甲基淀粉的制备研究
2.
Synthesis of konjac glucomannan ester of palmitic acid and determination of degree of substitution
棕榈酸葡甘聚糖酯的合成及取代度的测定
3.
Cellulose benzoate(CB),the degree of substitution(DS) 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(CB)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(D S),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。
2) substitution degree
取代度
1.
Test of Influence of Substitution Degree on Cationic Starch Property;
取代度对阳离子淀粉性能的影响试验
2.
Determination of substitution degree of N-succinyl-chitosan by conductometric titration;
电导滴定法测定N-琥珀酰壳聚糖取代度
3.
Preparation of starch succinate with low substitution degree(DS) was studied by using corn starch as raw material,succinic anhydride as esterifying reagent,water as solvent and sodium hydroxide as catalyst.
以玉米淀粉为原料,丁二酸酐为酯化剂,以水为媒介,氢氧化钠为催化剂对低取代度淀粉丁二酸酯的制备工艺进行了研究。
3) DS
取代度
1.
Native starch was modified by etherification with acrylonitrile,and films were prepared from blends of polyvinyl alcohol(PVA) with cyanoethyl starch(CES) with different degrees of substitution(DS) by solvent casting methods.
研究了原淀粉通过丙烯腈醚化改性,用不同取代度的氰乙基淀粉与聚乙烯醇(PVA)利用溶剂流延法共混制膜。
2.
The treatment effect of slightly polluted water with modified guar and the influence of such factor as reaction temperature,reaction time,consumption of chloroacetic acid,consumption of sodium hydroxide,ethanol dosage,and stirring time on the DS of carboxyl methyl guar were investigated,and the optimal reaction conditions for the preparation were also determined.
研究改性瓜尔胶处理微污染水的效果,以及反应温度、反应时间、氯乙酸用量、碱用量、酒精用量和搅拌时间等因素对羧甲基瓜尔胶取代度的影响,确定制备的最佳反应条件。
3.
The results showed that the water reducing ratio of sulfonated starch is increased with the degree of substitution(DS).
结果表明:磺化淀粉减水率随磺酸基取代度增加而增加,当其取代度达到0。
4) substitution
[英][,sʌbsti'tju:ʃən] [美][,sʌbstə'tjuʃən]
取代度
1.
Through single factor and orthogonal experiments,the effects of reaction conditions on degree of substitution(DS)and apparent viscosity(η)were investigated,and the optimum reaction conditions were .
通过单因素和正交试验,对其改性反应条件进行优化,以产物取代度(DS)和表观粘度(η)为评价指标,综合二者确定羧甲基化的最佳条件为:55℃、pH12反应3。
2.
The best technical conditions were determined to obtain higher substitution CMC by the orthogonal experiment.
以取代度为目标,用正交实验方法确定了最佳工艺条件,制得较高取代度CMC。
3.
All kinds effects of reaction on substitution of products were discussed through many experiments.
系统地研究以玉米高直链淀粉、环氧丙烷为主要原料,采用微乳化法合成羟丙基高直链淀粉工艺,通过实验探讨各影响因素对产品取代度的影响;并用X射线衍射仪、电子扫描仪等对产品性能进行分析。
5) substituting degree
取代度
1.
Preparation of O-carboxymethyl chitosan oligosaccharide with different substituting degrees and their antioxidant activity;
不同取代度O-羧甲基壳聚糖的抗氧化性能
2.
The factors affecting substituting degree were investigated.
考察了影响取代度的各因素,确定了最佳工艺条件。
6) high degree of substitution
高取代度
1.
Synthesis and characterization of starch acetate of high degree of substitution;
高取代度淀粉醋酸酯的合成及表征
2.
Study on preparation of starch acetate with high degree of substitution by microwave with the high amylose
高直链淀粉微波制备高取代度醋酸酯淀粉的研究
3.
Acetylated starches with high degree of substitution were synthesized from cornstarch with acetic anhydride as esterifying agent and methanesulphonic acid as catalyst.
以玉米淀粉为原料,醋酸酐为酯化剂,甲烷磺酸为催化剂,制备高取代度淀粉醋酸酯。
补充资料：取代度
分子式：
CAS号：
性质：常用DS表示。纤维素醚是纤维素分子莲上的羟基为醚基取代的产物，平均每个失水葡萄糖单元上被反应试剂取代的羟基数目，称为取代度。由于纤维素分子链中每个失水葡萄糖单元上只有3个羟基能被取代，所以取代度只能小于或等于3。当纤维素醚形成侧向分歧的醚时，平均每个失水葡萄糖单元上所结合的取代醚基总量用摩尔取代度（molar degree of substitution, MS）表示。MS的大小与侧链形成的程度有关，理论上MS值可以是无限的。对纤维素烷基、羧烷基和酰基衍生物，DS和MS是相同的；对纤维素羟烷基衍生物，当一个羟烷基被引入纤维素分子链时，就形成一个附加的羟基，这个羟基本身又可被羟烷基化，因而，在纤维素分子链上可形成相当长的侧链，所以通常，MS大于DS，MS大小视侧链形成的程度而定。
CAS号：
性质：常用DS表示。纤维素醚是纤维素分子莲上的羟基为醚基取代的产物，平均每个失水葡萄糖单元上被反应试剂取代的羟基数目，称为取代度。由于纤维素分子链中每个失水葡萄糖单元上只有3个羟基能被取代，所以取代度只能小于或等于3。当纤维素醚形成侧向分歧的醚时，平均每个失水葡萄糖单元上所结合的取代醚基总量用摩尔取代度（molar degree of substitution, MS）表示。MS的大小与侧链形成的程度有关，理论上MS值可以是无限的。对纤维素烷基、羧烷基和酰基衍生物，DS和MS是相同的；对纤维素羟烷基衍生物，当一个羟烷基被引入纤维素分子链时，就形成一个附加的羟基，这个羟基本身又可被羟烷基化，因而，在纤维素分子链上可形成相当长的侧链，所以通常，MS大于DS，MS大小视侧链形成的程度而定。
说明：补充资料仅用于学习参考，请勿用于其它任何用途。
参考词条