h****6
发帖数: 229 | 1 Don't know if this is the right forum to ask. but any way, does anyone know
who makes carboxyl magnetic beads 磁珠 (polystyrene coated, not silica coated)in
China? |
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f***a
发帖数: 11477 | 2 【 以下文字转载自 NanoST 讨论区 】
发信人: frada (微风轻哨), 信区: NanoST
标 题: 请教magnetic beads做TEM的问题
发信站: BBS 未名空间站 (Mon Jan 3 12:45:40 2011, 美东)
第一次做TEM，问题很多
我的mag beads比较大, 1 um直径
我就是用滴加5ul干在grid(200 mesh copper, carbon type-B),干5分钟
然后用一个什么放射性的东西染色5分钟，再冲洗，再干5分钟
结果发现只有非常少的bead在膜的边缘地带吊着
但是同样的步骤对于20nm 的普通 gold nanoparticle就没有问题
可以很均匀地分布在整个网上
谁知道这是什么原因啊
是因为有磁性的原因，还是因为尺寸太大的原因
如果是尺寸的原因，那么应该怎么操作呢
如果是磁性的原因，一般mag beads应该怎么样才可以在 TEM下保持住并看到呢 |
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o****e
发帖数: 1011 | 3 我不确定为什么你的magnetic beads最后很少“粘”在grid上。
你不妨提高原始样品的浓度，或者至少让原始样品在grid上dry得久些
（让溶剂多挥发些），希望这样最后粘在grid上的beads多些。你可以
优化一下条件（air dry 5min -->“完全”dry）。
我做的SEM/TEM实验也并不多。就是提个建议，抛砖引玉吧。 |
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m****o
发帖数: 51 | 4 我的样品LiFePO4可能含有极其微量的纳米铁粉,可能含量小于1ppm,大家觉得
用Magnetic Property可以检测出来吗? |
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z****u
发帖数: 134 | 5 求审稿机会，研究方向包括thin film growth(CVD,ALD,PVD,etc.), organic/
molecular magnets, charge-transfer salts, spintronics. 有一定审稿经验，如果
有朋友可以推荐审稿机会，请发站内信给我，我会提供详细的背景材料和简历，非常感
谢。 |
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m*******V
发帖数: 1022 | 6 哦，谢谢看来是好学校。
我刚刚查到这样一段话：
磁力學校之所以命名為magnet school，係因為學校有如磁鐵般的吸引了藝術、科學、或
任何一項特優稟賦的學童，如果有同樣優異稟賦的學童基於共同的興趣，在一起學習自然
能夠廢除種族隔離。
在傳統的學區制與沒有擇校權的教育政策中，磁力學校成為美國教改的主力。每一所
磁力學校都有其具特色的教育哲學或專擅的課程吸引學生來分享其教學。在開放註冊的政
策下，磁力學校原是為了廢除種族隔離。美國北方城市學校為廢除種族隔離，磁力學校最
早出現於70年代的威斯康辛州密耳瓦基與辛辛納提，連續三十年，已擴展到了北方及南方
的城市。（Elmore and Fuller）
現在，磁力學校是美國家長擇校權中最流行的選擇。在1991-92年間，全美有2,400學
區施辦磁力學校，一百二十萬名學生參與磁力學校的活動，七百萬美元支持此一計畫的實
施。（Steel and Levine, 1994）到了1996年，已有超過一百五十萬名年輕孩子參加過磁
力學校，並有十二萬名學生等候參加。（Black, 1996）雖然磁力學校原來的主要目的是
為剷除校園的種 |
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l***g
发帖数: 1035 | 7 any recommendation for the high power (kw) magnetics design sw? i can do by
hand but it's too tedious.. |
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a*******f
发帖数: 3 | 8 帮国内朋友问，
electronic magnetic哪些学校比较好呢？他这个方向是不是不进入军工就找不到工作啊？这个方向有权威排名么？
谢谢 |
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t*1
发帖数: 124 | 9 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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m******y
发帖数: 22 | 10 alternating magnetic field :
up to 400 gauss, 100--400kHz
using solenoid: number of turns, diameter of the solenoid, the kind of the
winding meterial (Is copper good to stand strong current?), cooling system,
what kind of genetor I should choose?
I know there are many issues involved.
Is there any experimental design book regarding this?
Can anyone give me any hints on how to start with ?
any advice is highly appreciated.
you can also email me at z***[email protected]
thanks a lot. |
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n********e
发帖数: 133 | 11 【 以下文字转载自 JobHunting 讨论区 】
发信人: naughtylee (都来fit), 信区: JobHunting
标 题: job opportunity in Wuhan High Magnetic Field Center
发信站: BBS 未名空间站 (Tue Mar 2 15:34:37 2010, 美东)
国家脉冲强磁场科学中心（筹）招聘
根据工作需要，目前国家脉冲强磁场科学中心（筹）招聘电机与电器、脉冲电源
、测量与控制、低温以及物理等方面的教师 (professor/associate professor) 与
工程师 (lead/senior engineer)，待遇从优，欢迎有意者加入。
1.电磁技术研究方向教师/工程师：
有较强电气工程理论基础；
负责电磁设计、计算、仿真，配合完成实验测试工作；
★有超导、磁体、低温技术或有限元软件使用经验者优先。
2.脉冲电源技术方向教师/工程师：
负责电容储能型脉冲电源系统与脉冲发电机型电源系统的保护、控制和技术集成
方面的工作；
具有脉冲电容器、脉冲发电机及电力电子技术应 |
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A*******g
发帖数: 225 | 12 求审稿
Magnetic materials, Shape memory alloys, and Mechanics of materials
目前7篇文章，5篇一作，影响因子一般。目前没有独立审稿，只帮导师审过两篇。现在
计划申请绿卡，所以想早些攒审稿经验。希望各位大牛帮忙。
请站内信联系，我可以把我的CV/Resume发过去，万分感谢 |
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b*****h
发帖数: 29 | 13 some suggestion for me to use 二茂铁衍生物 synthesis magnetic polymer is
correct or not?
since I have check the paper, this kind of polymer or even monomer itself is
paramagnetic that means non-mag at least in room temperature.
can some one know anything or have found any paper with this?
how about Sol-gel or composites?
or ferroplating?
I am amazed by how hard to fabricate some magneic fibres array!
maybe i should found another way to simulate the cilia movement.
since I can not use this as a large r |
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a***n
发帖数: 578 | 14 I seldom told new ideas to strangers. But I am willing to think of unexplained
experiment or obseveration. Anyway, permanent magnetic polymer or molecular
crystal are just recent proposed concepts. There are only few researches about
it.
It may waste time to look at that direction.
itself |
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d****i
发帖数: 360 | 15 Just made some pure Ni nanoparticles. But they are not attached on the
sir-bar. So, Is pure Ni nanoparticle magnetic ot not? And is there people
making any bimetallic particles with one element in the core and the other
element metal growing like some extanding arms on the core? |
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c*s
发帖数: 2145 | 16 Is pure Ni nanoparticle magnetic, hehe
people
other |
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h****6
发帖数: 229 | 17 Don't know if this is the right forum to ask. but any way, does anyone know
who makes carboxyl magnetic beads 磁珠(polystyrene coated, not silica coated)in
China? |
|
d*****y
发帖数: 2 | 18 Hi, all
The international Journal of Magnetic Resonance Imaging is calling for paper!
Any paper associated or related with MRI is welcome and very much
appreciated. If you want to try and have some of your paper published,
please let us know!!Reach us at e****[email protected]
There is detailed information attached about the Journal and paper
submission.
Thanks! Hope to get to know you soon! |
|
n********e
发帖数: 133 | 19 【 以下文字转载自 JobHunting 讨论区 】
发信人: naughtylee (都来fit), 信区: JobHunting
标 题: job opportunity in Wuhan High Magnetic Field Center
发信站: BBS 未名空间站 (Tue Mar 2 15:34:37 2010, 美东)
国家脉冲强磁场科学中心（筹）招聘
根据工作需要，目前国家脉冲强磁场科学中心（筹）招聘电机与电器、脉冲电源
、测量与控制、低温以及物理等方面的教师 (professor/associate professor) 与
工程师 (lead/senior engineer)，待遇从优，欢迎有意者加入。
1.电磁技术研究方向教师/工程师：
有较强电气工程理论基础；
负责电磁设计、计算、仿真，配合完成实验测试工作；
★有超导、磁体、低温技术或有限元软件使用经验者优先。
2.脉冲电源技术方向教师/工程师：
负责电容储能型脉冲电源系统与脉冲发电机型电源系统的保护、控制和技术集成
方面的工作；
具有脉冲电容器、脉冲发电机及电力电子技术应 |
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m***c
发帖数: 1403 | 20 是因为magnetic ordering消失了么 |
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m*****3
发帖数: 201 | 21 小弟现在主要研究方向magnetic nanostructure, fabrication and characterization
主要是一些exchange bias system，multiferroics
希望各位大神给小弟提携提携多给点机会
版内联系
谢谢了！ |
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f*******s
发帖数: 26 | 22 Area: magnetic materials, thin films, materials characterization using TEM
and atom probe
谢谢帮忙.站内联系. |
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A*******g
发帖数: 225 | 23 求审稿
Magnetic materials, Shape memory alloys, and Mechanics of materials
目前7篇文章，5篇一作，影响因子一般。目前没有独立审稿，只帮导师审过两篇。现在
计划申请绿卡，所以想早些攒审稿经验。希望各位大牛帮忙。
请站内信联系，我可以把我的CV/Resume发过去，万分感谢 |
|
x*******n
发帖数: 185 | 24 magnetic hysteresis loss is due to domain wall motion. if the domain size of
Ni is much smaller than your particle size. then the difference between the
bulk and the powder would be small. However, the bigger the sample is, the
bigger your domain tend to be. so, i would say the hysteresis loss would be
different. |
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m********r
发帖数: 811 | 25 What is the shortest non-zero lenght, L, of a magnetic quadrupole that is
imaging in the horizontal plane, with omega=9 ? |
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d*****y
发帖数: 2 | 26 Hi, all
The international Journal of Magnetic Resonance Imaging is calling for paper!
Any paper associated or related with MRI is welcome and very much
appreciated. If you want to try and have some of your paper published,
please let us know!!Reach us at e****[email protected]
There is detailed information attached about the Journal and paper
submission.
Thanks! Hope to get to know you soon! |
|
w*****y
发帖数: 303 | 27 Hei anyone know how to calculate the force on a piece of
iron (or superparamagnetic bead) by a magnetic force?
3x a million. |
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w*****y
发帖数: 303 | 28 好象是。材料是paramagnetic,我找到一个公式，
是和磁场强度，磁场强度梯度成正比，还和
magnetic susceptbility成正比。
但最后一个参数每本书定义不一样，弄得我很
糊涂:(
多谢各位。 |
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h******e
发帖数: 3 | 29
I think it should be:
Energy densty =-M*H
Force=-gradient E*V
where M=a*H, a is the permiability of the material, V is the
volume of the piece.
if the material or the field is not uniform, Force =
integral of (minus Gradiant E) by dV.
The problem is that the permiability changes by H and the
material's magnetization history and actually also the shape
of the piece(which decides the magnetostatic energy of the
piece), whether the iron has cristalline anisotropy and
maybe the magnetostriction of |
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w*****y
发帖数: 303 | 30 事情是这样的，我需要算一个superparamagnetic bead在
磁场中的受力，我找到一个公式
F=x*dB/dz*B
it says x is susceptibility. But as I know it is a
dimensionless parameter. So I need to find what is x.
What is more, I know the bead's magnetic susceptibility
is 1.0E-2(CGS units) which makes me more puzzling:(
Thanks a lot. |
|
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s*****e
发帖数: 6 | 32 请问哪里可以买到10ppm以内的小型的permanent magnet(~0.5T)，多谢多谢 |
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w*******y
发帖数: 60932 | 33 This "deal" is not for everyone, but thought I'd post it anyways. These
might make good gifts for kids. I've always wanted to try these myself.
Here is a video:
http://www.youtube.com/watch?v=Y8YqTZQcZb8
of these tiny magnets in action.
quote
Summer is full of balls: baseballs, softballs, soccer balls, wiffle balls,
beach balls. Why not Buckyballs? Buy two sets of Buckyballs and get one free
! Use the code HOTBALLS through 6/26/2010 at 12 midnight ET.
Link:
http://www.thinkgeek.com/geektoys/sc |
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w*******y
发帖数: 60932 | 34 EveryDaySource
20 Pieces 8mm Super Strong Rare-Earth RE Magnets
$3.99 - $3 code SMGNT
= $0.99 with free shipping
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w*******y
发帖数: 60932 | 37 Everydaysour ce
20-Piece 8mm Super Strong Rare-Earth RE Magnets
$4.99 - $4 code S9PSRE
= $0.99 with free shipping
*deal starts 9/23 at 3 PM PST*
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w*******y
发帖数: 60932 | 39 JC Penney
Kid's L-Shaped Double Easel with Stool:
http://www5.jcpenney.com/jcp/X6.aspx?GrpTyp=PRD&ItemID=196cf10&Ntt=L-Shaped Double Easel w/ Stool&hdnOnGo=true&Ne=840 4 877 878 5 961 6 29 3 598 11 15 12 506 10 23 585 596 1031 8 18 904 903 969 949 833&submit search.y=5&SearchString=L-Shaped Double Easel w/ Stool&submit search.x=9&N=4294959029&Nao=0&SO=0&PSO=0&CmCatId=searchresults
$18.99
In-store pick up is free
L-shaped
magnetic board
chalk board
desk
storage tray
accessories
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w*******y
发帖数: 60932 | 41 I was looking for an affordable, good quality speech therapy toy for my boy
and ran across this. I ordered it when it was $11.95, which was actually
the best price by far at the time.
Now, it's down to $6.95. Solid reviews:
LeapFrog Fridge Talk Magnetic Wordplay Recorder:
http://www.amazon.com/gp/product/B00134V4NE
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w*******y
发帖数: 60932 | 45 1 Pack Bright 5 LED Head Lamp, Flash Function and Adjustable Head Band,
Removable Lamp with A Magnetic Button, Perfect for Garage use, Camping or
Outdoor Activities (More Details)
Coupon Code :MLCK248001020467NL1 limit 600 uses
Link:
http://www.meritline.com/led-flashlight-206-flesh---p-25400.asp
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w*******y
发帖数: 60932 | 49 Everydaysource
20-piece 8mm Super Strong Rare-Earth RE Magnets
$0.99 with code S0331WJBM
free shipping |
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w*******y
发帖数: 60932 | 50 Link:
http://shop.lego.com/en-US/LEGO-Brand-Toy-Story-Magnet-Set-Wood
I found this toy story minifig set for $3.48. They also have a female
minifig set and prince of persia set for $3.48. Toy story is backordered
and not expected to ship until 10/1 but this is a great price. I bought
enough to get free shipping and I'll tuck them away as gifts or ebay them.
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