c*********o
发帖数: 1734 | 1 【 以下文字转载自 EE 讨论区 】
发信人: chinesegogo (gogo), 信区: EE
标 题: Magnetic Stirrer 的问题，请教
发信站: BBS 未名空间站 (Tue Jul 20 20:11:18 2010, 美东)
版上各位大侠，不要笑我的问题太naive.
不知大家见没见过Magnetic Stirrer，见附图。基本上就是通过电产生磁场（可调），
之后带动Magnetic Stir bar（磁铁，外边镀的teflon)旋转，达到搅拌混合的目的。
我的问题是，同样的磁场强度下，如果用不同大小的Stir bar， Stir bar的转速一样
么？
我觉得不应该是一样的。 希望得到理论支持。
多谢。 |
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c*********o
发帖数: 1734 | 2 【 以下文字转载自 EE 讨论区 】
发信人: chinesegogo (gogo), 信区: EE
标 题: Magnetic Stirrer 的问题，请教
发信站: BBS 未名空间站 (Tue Jul 20 20:11:18 2010, 美东)
版上各位大侠，不要笑我的问题太naive.
不知大家见没见过Magnetic Stirrer，见附图。基本上就是通过电产生磁场（可调），
之后带动Magnetic Stir bar（磁铁，外边镀的teflon)旋转，达到搅拌混合的目的。
我的问题是，同样的磁场强度下，如果用不同大小的Stir bar， Stir bar的转速一样
么？
我觉得不应该是一样的。 希望得到理论支持。
多谢。 |
|
c*********o
发帖数: 1734 | 3 版上各位大侠，不要笑我的问题太naive.
不知大家见没见过Magnetic Stirrer，见附图。基本上就是通过电产生磁场（可调），
之后带动Magnetic Stir bar（磁铁，外边镀的teflon)旋转，达到搅拌混合的目的。
我的问题是，同样的磁场强度下，如果用不同大小的Stir bar， Stir bar的转速一样
么？
我觉得不应该是一样的。 希望得到理论支持。
多谢。 |
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F*V
发帖数: 3978 | 4 挪威杀人狂在宣言中多处提到中国 (2011-08-15 17:41:27)转载▼
信源：张翼博客｜编辑：2011-07-27｜
While a significant number of citizens in Islamic or Muslim countries are
directly hostile to Europeans, Chinese are usually just after your money. It
is unbearable to live the rest of your life in a country where there is a
constant and an overwhelming danger of being “Shanghaied”. My stepmother
was the Norwegian Vice Counsul in Shanghai and I know several Europeans
working there. They are willing to “cope” for the duration of thei... 阅读全帖 |
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s****n
发帖数: 786 | 5 原帖：http://www.xycq.net/forum/thread-233031-1-1.html
While a significant number of citizens in Islamic or Muslim countries are
directly hostile to Europeans, Chinese are usually just after your money. It
is unbearable to live the rest of your life in a country where there is a
constant and an overwhelming danger of being “Shanghaied”. My stepmother
was the Norwegian Vice Counsul in Shanghai and I know several Europeans
working there. They are willing to “cope” for the duration of their
company te... 阅读全帖 |
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S*R
发帖数: 1057 | 6 http://bbs.m4.cn/thread-3140729-1-1.html
While a significant number of citizens in Islamic or Muslim countries
are directly hostile to Europeans, Chinese are usually just after your money
. It is unbearable to live the rest of your life in a country where there is
a constant and an overwhelming danger of being “Shanghaied”. My
stepmother was the Norwegian Vice Counsul in Shanghai and I know several
Europeans working there. They are willing to “cope” for the duration of
their company term, ... 阅读全帖 |
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w*********g
发帖数: 30882 | 7 挪威杀人狂在宣言中多处提到中国 (2011-08-15 17:41:27)转载▼
信源：张翼博客｜编辑：2011-07-27｜
While a significant number of citizens in Islamic or Muslim countries are
directly hostile to Europeans, Chinese are usually just after your money. It
is unbearable to live the rest of your life in a country where there is a
constant and an overwhelming danger of being “Shanghaied”. My stepmother
was the Norwegian Vice Counsul in Shanghai and I know several Europeans
working there. They are willing to “cope” for the duration of thei... 阅读全帖 |
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v**e
发帖数: 8422 | 11 【 以下文字转载自 Military 讨论区 】
发信人: siphon (西风), 信区: Military
标 题: 挪威枪手赞道：阿里巴巴是很好的网站
发信站: BBS 未名空间站 (Wed Jul 27 12:23:46 2011, 美东)
原帖：http://www.xycq.net/forum/thread-233031-1-1.html
While a significant number of citizens in Islamic or Muslim countries are
directly hostile to Europeans, Chinese are usually just after your money. It
is unbearable to live the rest of your life in a country where there is a
constant and an overwhelming danger of being “Shanghaied”. My stepmother
was the Norwegian Vice C... 阅读全帖 |
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p********n
发帖数: 1538 | 12 【 以下文字转载自 SanFrancisco 讨论区 】
发信人: pleasanton (kiterunner), 信区: SanFrancisco
标 题: 5分钟清爽好喝的lemonade
发信站: BBS 未名空间站 (Wed Jul 29 22:53:20 2009, 美东)
炎热的夏天，如果你家里有：4个柠檬，半杯 sugar，冰水，冰块，简易果汁机，5分钟全家可以喝上好喝的lemonade（如果喜欢甜点的，后面还是可以加糖）:
1。柠檬一刀为2
2。上果汁机squeeze lemon juice
3。把lemon juice和sugar倒入pitcher，然后用搅拌棒（stirrer)充分溶解juice和
sugar
4。加入水和冰块，满满的一pitcher家庭装lemonade就好了
5。这个lemonade和外面卖的偏黄还是cherry look的比较多的是天然健康。 |
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l**********i
发帖数: 11748 | 13 搜了一下
叫garlic plate
果然好贵
不过还看见一个叫
Garlic Crusher Peeler Spice Mincer Stirrer Presser Slicer Ginger Clear
Kitchen Tool Useful 2pcs
能给弄成蒜末
便宜点
楼主可以去看看 |
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l**********i
发帖数: 11748 | 14 搜了一下
叫garlic plate
果然好贵
不过还看见一个叫
Garlic Crusher Peeler Spice Mincer Stirrer Presser Slicer Ginger Clear
Kitchen Tool Useful 2pcs
能给弄成蒜末
便宜点
楼主可以去看看 |
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h*********r
发帖数: 2844 | 15 你是真正的搅屎棍，shit stirrer. 古板人气全靠你了。 |
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o********n
发帖数: 1329 | 16 我现在真的觉得你是老刑派来的了。
shit stirrer
LOL |
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d******e
发帖数: 1073 | 17 shit stirrer难道不是大家都公认researchba么。。。 |
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k**********i
发帖数: 8706 | 18 http://www2.tech.purdue.edu/cg/courses/cgt411/covey/48_laws_of_
The 48 Laws of Power
by Robert Greene and Joost Elffers
Law 1
Never Outshine the Master
Always make those above you feel comfortably superior. In your desire to
please or impress them, do not go too far in displaying your talents or you
might accomplish the opposite – inspire fear and insecurity. Make your
masters appear more brilliant than they are and you will attain the heights
of power.
Law 2
Never put too Much Trust in Friend... 阅读全帖 |
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a******e
发帖数: 36306 | 19 ☆─────────────────────────────────────☆
kelvinchufei (Kelvin) 于 (Mon Jan 30 16:01:38 2012, 美东) 提到:
The 48 Laws Of Power
by Robert Greene
☆─────────────────────────────────────☆
kelvinchufei (Kelvin) 于 (Wed Feb 1 16:22:45 2012, 美东) 提到:
http://www2.tech.purdue.edu/cg/courses/cgt411/covey/48_laws_of_
The 48 Laws of Power
by Robert Greene and Joost Elffers
Law 1
Never Outshine the Master
Always make those above you feel comfortably superior. In your desire to
please or impress them, do ... 阅读全帖 |
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R******d
发帖数: 5739 | 20
depends on what you need. if you need stirring, I really don't know what
you can do other than buying a stirrer. for hot plate, if just water, use a
hair dryer to heat up the flask, make sure no volatile solvents like
ethanol. |
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e***h
发帖数: 2791 | 22 你这是什么理解力要不就是SH..T STIRRER. |
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e***h
发帖数: 2791 | 23 你这是什么理解力要不就是SH..T STIRRER. |
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c****t
发帖数: 19049 | 24 THE GHASTLY ORDEAL OF TIMOTHY CAVENDISH
One bright dusk, four, five, no, my God, six summers ago, I strolled along a
Greenwich
avenue of mature chestnuts and mock oranges in a state of grace. Those
Regency residences
number among London’s costliest properties, but should you ever inherit one
, dear Reader, sell
it, don’t live in it. Houses like these secrete some dark sorcery that
transforms their owners into
fruitcakes. One such victim, an ex-chief of Rhodesian police, had, on the
evening in qu... 阅读全帖 |
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d********u
发帖数: 5383 | 25 围观shit stirrer。你说你偷就偷了，还满世界地嚷嚷，生怕别人不知道你聪明地都会
偷了，真够井的 |
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d********u
发帖数: 5383 | 26 去篮球版，问“那个shit stirrer怎么老不来了？”，看看大家回的是不是“在问
GOODBUG吗”？
看上面的ID，很有喜感。我就不查了，免费给大家科普一下。这位清华千人大系出来的
喜爱撒谎（大庭广众之下的撒谎哦），撒泼打滚，从股版，篮球，PDA到本版，每次都
是被抽得没人模样。整天宗教般的“JAVA就是好”，30多了还跟傻逼似的。可能以前被
MS解雇过，MS业绩不好，丫笑得就跟鸡似的；MS股价一涨，丫立刻跟大傻逼似的来句“
其实未必是好事”。我说丫祖上是卖的，信不？
人SB好歹220亿身家，丫一马公还替人担心，我说丫是傻逼，恐怕傻逼都觉得是侮辱。
这种傻逼我是见一次骂一次。 |
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q****e
发帖数: 3660 | 27 一个反应器，要求可以加热到250以上，可以使用OVERHEAD STIRRER，反应器本身有刻
度，从5个CC开始，反应器有口要接一个DISTILLATION 的装置。现在要测一个反映的副
反应的量，需要知道副反应产物沉淀以后有多少CC，有这样的反应器吗？哪里可以买到
呢？谢谢 |
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e****2
发帖数: 2723 | 28 Sunday May 15 - Day 14: At the last batch of preparing pure acetylsalicylic
acid my hot plate stirrer broke down. The magnetic mechanism stopped working
. Fuck, Chinese piece of shit equipment, I should have rather paid more to
get good European quality machinery..
搅拌器中国产，有哪个实验室是这样的？ |
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S*****n
发帖数: 6055 | 29 yes
now my job only plays with beakers and stirrers
miss those instruments so much |
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p******s
发帖数: 193 | 30 想照着2009年邓春晖Angew chemie的Fe3O4@SiO2@PMMA 的文章，做这个东西，用来接功
能蛋白
大家看看，最后的聚合不需要引发剂么？
前文不赘述了，Fe3O4@SiO2-MPS 已经合成好了
要往上面修饰PMMA了，
The sandwich structured Fe3O4@SiO2@PMMA microspheres were synthesized via an
aqueous-phase radical polymerization. Typically, in a three-necked round
bottom flask (100 mL) equipped with a mechanical stirrer, a refluxing
condenser, and a nitrogen inlet, 10 mL of ethanol dispersion of Fe3O4@SiO2-
MPS microspheres were mixed
with 50 mL of aqueous solution containing 5.0 mg of ... 阅读全帖 |
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y*******w
发帖数: 5917 | 31 不明白你的推理，难道转速不是由磁场的转速决定么？如果那样，转速和大小什么关系。 |
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t*1
发帖数: 124 | 32 one simple approve will be(not sure if it is correct):
with same magnetic flux density, let's assume it produce the same energy.
since the K.E.=0.5mV^2, mass is different, therefore, V is different. |
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c*********o
发帖数: 1734 | 33 K和E都是啥啊？ 这里的V是指直线速度么？Thanks. |
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t*1
发帖数: 124 | 34 kinetic energy. v is the stir's body velocity. |
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c*w
发帖数: 50 | 35 来自主题: Macromolecules版 - 换种说法 what polydispersity means:分布宽？
if you devote some time in method 1, you could get something maningful. should
doing enough experiments to find the feeling of obtaining monodispersity PLGA
particles.some factors: the stirrer used, the beaker shape(high and slim one
better), surfactant concentration..
【 在 boss (养蜂人) 的大作中提到: 】
溶
高分子溶解在有机溶剂中，在超声波的作用下从微孔中inject到溶有surfactant
不 |
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w*******n
发帖数: 5 | 36 来自主题: Macromolecules版 - 在线急问 想请教各位兄弟姐妹，在做聚酯合成的时候，应该使用什么搅拌装置可以在机械搅拌的
情况仍旧达到真空度0.5mmHg？反应器使用的是24/40圆底烧瓶。在网上找了很多
stirrer bearing,都不管用。。。觉得这个应该是个很基本的技术问题吧，可是自己太
笨，一直都找不到。还请知道的朋友指导一下啦，多谢！ |
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p******s
发帖数: 193 | 37 【 以下文字转载自 Chemistry 讨论区 】
发信人: pastoris (锦涛喇嘛), 信区: Chemistry
标 题: 求指教一个纳米fe3o4@sio2@pmma合成中，pmma的聚合条件
发信站: BBS 未名空间站 (Tue Apr 22 10:27:16 2014, 美东)
想照着2009年邓春晖Angew chemie的Fe3O4@SiO2@PMMA 的文章，做这个东西，用来接功
能蛋白
大家看看，最后的聚合不需要引发剂么？
前文不赘述了，Fe3O4@SiO2-MPS 已经合成好了
要往上面修饰PMMA了，
The sandwich structured Fe3O4@SiO2@PMMA microspheres were synthesized via an
aqueous-phase radical polymerization. Typically, in a three-necked round
bottom flask (100 mL) equipped with a mechanical stirrer, a refluxing
conden... 阅读全帖 |
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q*d
发帖数: 22178 | 38 不同的磁铁:
1.磁矩不一样
2.转动惯量不一样
转速一般来说当然不一样
被子底下那个白的是什么? |
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c*********o
发帖数: 1734 | 39 那个应该是一块aluminum foil.
有什么办法能测量磁铁的准确转速么？ |
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q*d
发帖数: 22178 | 40 我说那个烧杯低下那个白的大胶囊一样的东西是什么 |
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c*********o
发帖数: 1734 | 41 那个就是mafnetic stir bar，有大有小，用来搅拌混合烧杯里的液体的。
我的问题就是如果换一个小一点的，同样磁场强度下，转速是不是就变了 |
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