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【多选题】
关于 3,5- 二硝基水杨酸测定样品中总糖和还原性糖含量的原理,下列哪些说法正确?
A.
还原性糖在碱性溶液中，与3,5-二硝基水杨酸（DNS）共热后生成桔红色物质，它在540nm处有最大光吸收
B.
在一定浓度范围内，A 540 与还原糖的浓度呈线性关系，利用比色法即可测定样品中的还原性糖含量
C.
样品在酸性溶液中、100℃沸水浴彻底水解生成还原性糖
D.
样品在50℃恒温水浴中可溶解出还原性糖
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