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- 求20篇以上关于荧光探针开发与研究进程的外文文献
2018-12-07 01:01:31
346
0
- 求几篇关于低频信号发生器的外文文献
- 帮个忙发下急用... 帮个忙发下急用 展开
2014-03-09 11:42:41
404
2
- 帮忙寻找外文文献,关于光学的
- 需要一篇用衍射的方法测量光波波长的外文文献资料。本人已经找了很久了就是找不到合适的,如果哪位大侠找到和我意的,真是不惜一切代价都愿意了。
2010-11-04 14:22:45
500
1
- 求一篇关于锡的前沿研究文献
2014-12-01 14:14:35
472
1
- 关于气体传感器或可燃气体报警器的外文文献
- 字数3000字左右,Z好能翻译成汉语。跪求!!!!!!!!!!!!!!!!!!!!
2016-04-30 11:31:56
404
1
- 求几篇文献!!关于气相色谱 液液微萃取 测定酚类化合物!!(外文)
- 各位牛人帮个忙!文献Z好要包含标题给出的要求的几个关键词,有涉及到的也行。如果能有翻译的就更更好了,保证再加分给你!!还有关于酚类萃取剂的选用也可以!!!
2009-08-03 00:17:33
449
1
- 急求关于服装类的外文参考文献
- 急需关于服装类的外文参考文献,哪位高人请帮忙~~~~要3-6篇... 急需关于服装类的外文参考文献,哪位高人请帮忙~~~~ 要3-6篇 展开
2018-11-20 03:55:58
242
0
- 急求一篇关于labview虚拟仪器的外文文献及3000字左右的中文翻译 ,急
- 邮箱576642385@qq.com谢谢... 邮箱 576642385@qq.com 谢谢 展开
2011-04-11 00:18:44
377
3
- 急求一篇关于labview虚拟仪器的外文文献及2000到3000字的中文翻译 ,急
2018-11-24 17:03:19
245
0
- 求助,光电传感器的外文文献!毕业论文用
- 3000字左右,外文翻译,光带或者光敏传感器的外文翻译!
2018-11-24 16:56:55
287
0
- 跪求一篇亚波长光栅外文文献:
- M. Pfeffer, “Nanotechnology in optics advances subwavelength-structures surfaces,” Europhotonics, pp 34, October/November 2003
2011-10-08 10:06:48
560
3
- 关于组态软件的设计与开发
- 谁能解释一下什么是组态软件?如何开发组态软件,用什么语言可以开发组态软件?VB C C++ 又可以的吗
2018-11-10 17:20:50
333
0
- 求一篇关于等精度频率计的英文文献,要三年内发表的,3000英文单词以上
2017-06-03 11:19:32
332
1
- 外文文献 基于MCU的信号发生器 做毕业论文外文翻译用的,谢谢了,
2015-01-23 07:15:40
329
1
- 找一篇关于食品安全和一篇关于食品检测的英语文献 要求2万字以上
- Z好直接是英语文章别给我一个网站让我自己找一定是关于食品安全和食品检测的谢谢................... Z好直接是英语文章 别给我一个网站让我自己找 一定是关于食品安全和食品检测的谢谢 ................ 展开
2008-02-25 03:16:36
228
1
- 求1篇关于纳米材料的英文文献,并有中文翻译
- 求1篇关于纳米材料的英文文献,并有中文翻译,谢谢,急急急!~~~~~~~~
2013-12-22 07:23:02
560
1
- 谁能告我关于薄层色谱法的一篇外文文献,我要翻译。谢谢了
2007-04-04 13:09:54
387
1
- 求一篇关于自动洗瓶机的英文文献及中文翻译
- 求一篇关于自动洗瓶机的英文文献及中文翻译,中文翻译字数在5000字左右,看过后给分,以免使胡乱翻译的。急求啊~~~~~~~~~~~~~~有意者可以发送至邮箱jay55111@sina.com如果有人有的话,... 求一篇关于自动洗瓶机的英文文献及中文翻译,中文翻译字数在5000字左右,看过后给分,以免使胡乱翻译的。急求啊~~~~~~~~~~~~~~有意者可以发送至邮箱jay55111@sina.com 如果有人有的话,再加100分,有QQ为证,416975023,今晚12点前截止 展开
2011-02-11 01:34:58
568
2
- 文献求翻译
- Since the formation of a titanacyclopropane en route to cyclopropylamines can only occur with alkylmagnesium halides that contain a b-hydrogen atom, Grignard reagents without b-hydrogens appeared to be the most promising reagents for th... Since the formation of a titanacyclopropane en route to cyclopropylamines can only occur with alkylmagnesium halides that contain a b-hydrogen atom, Grignard reagents without b-hydrogens appeared to be the most promising reagents for the synthesis of primary tert-alkylamines from nitriles (Scheme 1). Thus propionitrile (1a), phenylmagnesium bromide (2) and Ti(Oi-Pr)4 were chosen to optimize the reaction conditions. In the protocol for the synthesis of cyclopropylamines,10 Ti(Oi-Pr)4 is already present in the diethyl ether solution of a nitrile, before two equivalents of the Grignard reagent are added. As this did not appear to be optimal for the synthesis of primary tertalkylamines, the Grignard reagent was added before Ti(Oi-Pr)4. With 2 equivalents of PhMgBr, 0.1 equivalent of Ti(Oi-Pr)4, and 1 equivalent of propionitrile (1a), the primary tert-alkylamine 8a was not formed at all. With an equimolar quantity of Ti(Oi-Pr)4, the amine 8a was produced in a low yield (11%) but with 1 equivalent of Ti(Oi- Pr)4 and 3 equivalents of the Grignard reagent 2, a 60% yield of 8a was obtained. Monitoring of the reaction by workup of aliquots of the reaction mixture showed that the first addition of 2 to form the N-magnesio derivative of the corresponding imine was rapid, whereas the subsequent second addition of the Grignard reagent 2 required heating under reflux for up to 24 hours. In tetrahydrofuran instead of diethyl ether, the amine 8a was formed in a very low yield, if at all. 展开
2012-08-31 01:19:05
424
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