24小时热门版块排行榜    

查看: 774  |  回复: 5
当前主题已经存档。

wjg5118

金虫 (小有名气)

[交流] 【求助】 多糖羧甲基化的一个现象!

我在将多糖进行羧甲基化时出现了一个现象,没法解释了,求教各位大虾!~试验方法如下:

0.5克多糖加入异丙醇15mL, 室温搅拌30min,加入30%NaOH 10mL, 剧烈搅拌90min, 加入氯乙酸3克,50°C反应2h, 此时,停止搅拌,溶液分层,上层为澄清,下层为淡黄色液体,加入盐酸(少量),溶液变为均一,透析得到羧甲基化多糖0.6克

问题是,饭后为什么会分层啊,上下两层各是什么东西啊?

急问!!!

有知道的将送金币,多谢啊!

[ Last edited by ququxiao on 2008-9-20 at 19:03 ]
回复此楼
已阅   关注TA 给TA发消息 送TA红花 TA的回帖

wjg5118

金虫 (小有名气)

请帮我顶下啊!~
2楼2008-09-20 09:23:05
已阅   关注TA 给TA发消息 送TA红花 TA的回帖

modere

金虫 (正式写手)

www.polyindustry.com

wjg5118(金币+50,VIP+0):给出了合理的解释 多谢
ququxiao(金币-49,VIP+0):应modere要求,返还金币
ququxiao(金币-1,VIP+0):应modere要求,返还金币
顶一个,不懂
3楼2008-09-20 12:15:14
已阅   关注TA 给TA发消息 送TA红花 TA的回帖

modere

金虫 (正式写手)

www.polyindustry.com

★
ququxiao(金币+0,VIP+0):还是鼓励下,多来高分子版:)
ququxiao(金币+1,VIP+0):补上奖励的币币 :)
Synthesis of CM2SPG
The synthesis of CM2SPG with the 4 factors and 3 levels
orthogonal design L9 ( 34 ) was performed by a partially
variant of the method from reference[9 ] . Lyophilized SPG
(10 mg) was immersed by 1 mL isopropanol and the mix2
ture was kept at 40 ℃on a rotary shaker incubator at 120
rpm for 1 h ,then certain volume (67 ,100 or 134μL) of
30 % aqueous NaOH was added and kept at 40 ℃for 1
h. Certain volume ( 26 , 39 or 52 μL ) of 4 mol/ L
chloroacetic acid (CAA) was added to the mixture in a 50
~70 ℃oven for 2~4 h ,then 20 mL distilled water was
added and the mixture was neutralized to pH 6. 5~7 with
0. 1 mol/ L acetic acid.
“”“the mixture was neutralized to pH 6. 5~7 with
0. 1 mol/ L acetic acid.”“”“ 最后这句话
这一段源:自天然产物研究与开发Nat Prod Res Dev 2006 ,18 :5552557
你只是让它羧甲基化,没必要研究两部分是什么吧
4楼2008-09-20 13:09:47
已阅   关注TA 给TA发消息 送TA红花 TA的回帖

modere

金虫 (正式写手)

www.polyindustry.com

我考,你至于吗,50个金币。
好像我就是为了挣你金币似的
5楼2008-09-20 14:35:35
已阅   关注TA 给TA发消息 送TA红花 TA的回帖

wuwt

木虫 (正式写手)

顺道学习!

谢谢提供!
6楼2008-09-20 17:01:31
已阅   关注TA 给TA发消息 送TA红花 TA的回帖
相关版块跳转 我要订阅楼主 wjg5118 的主题更新
最具人气热帖推荐 [查看全部] 作者 回/看 最后发表
[考研] 售SCI一区T0P文章,我:8O.55.1.O.54,科目全,可伽急 +5 YHiw1gou1Eda 2026-11-10 8/400 2026-11-14 22:51 by Equinoxhua
[考博] 考博求助 10+3 社会实践对别 2026-11-08 3/150 2026-11-13 14:04 by 沐小虫252
[公派出国] 售SCI一区文章,我:8.O.551.O.5.4,科目全,可伽急 +4 G2rhSvqvhNzl 2026-11-10 5/250 2026-11-13 11:37 by Equinoxhua
[教师之家] 售SCI一区T0P文章,我:8.O.55.1.O.5.4,科目全,可+急 +4 1Nb0IVlmV6v0 2026-11-11 4/200 2026-11-13 11:18 by Equinoxhua
[教师之家] 售SCI-T0P文章,我:8O.5.5.1.O.54,科目齐全,可+急 +6 C6CRn66RYYXS 2026-11-10 6/300 2026-11-13 04:21 by Equinoxhua
[考博] 售SCI一区文章,我:8.O.55.1.O.54,科目齐全,可伽急 +4 TgvkbZZl9tqB 2026-11-11 6/300 2026-11-12 12:42 by ECLTXnJnRSXf
[公派出国] 售SCI一区T0P文章,我:8.O.55.1.O54,科目全,可伽急 +4 cdqGD6ftHmbl 2026-11-11 5/250 2026-11-12 12:28 by ECLTXnJnRSXf
[硕博家园] 售SCI一区T0P文章,我:8.O55.1.O.54,科目全,可十急 +4 cdqGD6ftHmbl 2026-11-11 4/200 2026-11-12 12:26 by ECLTXnJnRSXf
[考研] 售SCI一区T0P文章,我:8O.55.1.O.5.4,科目齐全,可+急 +7 czAiolzR0IJC 2026-11-10 9/450 2026-11-12 11:00 by HajghKOMynmz
[基金申请] 售SCI一区文章,我:8.O.551.O.5.4,科目全,可伽急 +5 G2rhSvqvhNzl 2026-11-10 7/350 2026-11-12 10:49 by HajghKOMynmz
[考博] 售SCI一区T0P文章,我:8.O.55.1.O54,科目全,可伽急 +4 C6CRn66RYYXS 2026-11-10 6/300 2026-11-12 10:27 by HajghKOMynmz
[教师之家] 售SCI一区T0P文章,我:8O.55.1.O.5.4,科目齐全,可+急 +3 C6CRn66RYYXS 2026-11-10 8/400 2026-11-12 10:16 by HajghKOMynmz
[公派出国] 售SCI-T0P文章,我:8O.5.5.1.O.54,科目齐全,可+急 +5 FChKX8meu1ds 2026-11-09 10/500 2026-11-12 09:52 by HajghKOMynmz
[考博] 售SCI一区T0P文章,我:8O.55.1.O.5.4,科目齐全,可+急 +5 FChKX8meu1ds 2026-11-09 8/400 2026-11-12 09:46 by HajghKOMynmz
[考研] 售SCI文章,我:8O.5.5.1O.54,科目全,可十急 +7 0TEMgxdT1eIw 2026-11-09 9/450 2026-11-12 09:24 by HajghKOMynmz
[教师之家] 售SCI一区T0P文章,我:8.O.55.1.O.54,科目齐全,可+急 +3 TgvkbZZl9tqB 2026-11-11 4/200 2026-11-12 08:15 by HajghKOMynmz
[公派出国] 售SCI一区T0P文章,我:8O.55.1.O.5.4,科目齐全,可+急 +3 czAiolzR0IJC 2026-11-10 5/250 2026-11-12 06:36 by 9fOTqj074tIg
[考博] 售SCI一区T0P文章,我:8.O.55.1.O.54,科目齐全,可+急 +3 FChKX8meu1ds 2026-11-09 8/400 2026-11-12 05:30 by 9fOTqj074tIg
[考研] 售SCI一区文章,我:8.O.55.1.O.54,科目齐全,可伽急 +6 FChKX8meu1ds 2026-11-09 9/450 2026-11-12 05:19 by 9fOTqj074tIg
[教师之家] 售SCI一区T0P文章,我:8.O55.1.O.54,科目全,可十急 +6 cqv1zKnzd7hr 2026-11-09 7/350 2026-11-12 00:44 by 9fOTqj074tIg
信息提示
请填处理意见