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全部话题 - 话题: ionization
1 2 3 4 5 下页 末页 (共5页)
z*********4
发帖数: 146
1
Electrospray Ionization Mass Spectrometry: Fundamentals, Instrumentation,
and Applications
by Richard B Cole (Editor), 1997, Wiley-Interscience,
Thanks a lot!
z*********4
发帖数: 146
2
Thanks a lot.
I still need the First Edition of it.
Electrospray Ionization Mass Spectrometry: Fundamentals, Instrumentation,
and Applications
by Richard B Cole (Editor), 1997, Wiley-Interscience.
Thank you very much!!
b***y
发帖数: 14281
3
来自主题: Military版 - 方励之的学术成就全记录
既然有人争论方的学术水平,就上网搜了一下。应该说这个水平对于一个junior
faculty来说可以算是很牛B了,但是对于老方这种senior的已经搞了一辈子的人来说,
就只能算so so。不要说是院士,离aps fellow的级别也还差了不少。引用率最高的一
篇文章还是95年到了arizona之后跟老外合作的,被引118次,这也是方唯一一篇被引用
上百次的文章。可见方励之89之前确实没有做出过什么重要的工作,他的名声和地位绝
对是靠政治得来的,当然其中部分的也是80年在中国搞科普所得,必须承认科普工作也是
有重要的社会意义的。
(BTW,有人说你这个搜索未必完整。不错,确实不能保证100%毫无遗漏。但是我
用的search engine is THE search engine everybody in this community uses today.
So, if any article is not found by this search engine, sadly, it simply doesn't matter,
because no one would ever n... 阅读全帖
w*********g
发帖数: 30882
4
平井宪夫揭示日本核电业惊天内幕——素人造核电,豆腐渣工程
作者:蜀中行 更新时间:2011-3-16
设施配管1级技士平井宪夫(1997年1月因癌症逝世)生前的最后吶喊。
/来自中华网社区 club.china.com/
/来自中华网社区 club.china.com/
关于平井宪夫:
1997年1月逝世。设施配管1级技士,核电事故调查国民会议顾问,核电劳工救济中
心代表,北陆电力志贺核电厂停止诉讼原告特别辅佐人,东北电力女川核电停止诉讼原
告特别辅佐人,福岛二号核电厂三号机运转停止诉讼原告证人。「核电劳工救济中心代
表」在他仙逝后,因后继无人关闭
"我不是反核运动家。这20年来,我一直在核电厂工作。社会上有听不完的拥核反
核理论,但我只想在这里告诉大家:「所谓的核电厂是这样一回事。」大部份的人都不
知道核电内部的实际情形。希望大家有耐心把这篇文章读完。所谓核电,跟各位所想的
或许有点出入。在那里,每天都有遭受放射线污染的工人,以及严重的岐视产生。
我的专长,是负责大型化学工场的内部配管施工与维修。快30岁时,日本掀起了一
阵核电建设的... 阅读全帖
h******i
发帖数: 661
5
你们学校ap能发这么多paper?
1989
Cosmological implications of quasar-galaxy associations, L.Z.Fang, Y.Q.Chu
and X.F. Zhu, Mod. Phys. Lett., 4, 887.
Geometrical optics in an inhomogeneous universe, L.Z.Fang and X.P.Wu,
Chinese Phys. Lett., 6, 233.
Quasar clustering and its cosmological implication, L.Z.Fang, Inter. J. Mod.
Phys. A4, 3477.
L'Osservatorio astronomico di Pechino: la sua storia, il presente, L.Z.Fang,
Scienza e Tecnica, Annuario della EST 88/89 404.
Overview on the frontier of high energy astr... 阅读全帖
S******8
发帖数: 24594
6
老方到美国后发的文章列表,你自己看吧:
1990
174. Biased clustering in a universe with hot dark matter and a cosmic
string, L.Z.Fang, S.P.Xiang and L.Yan, Astr. & Astrophys. 233, 1.
175. Periodicity of redshift distribution in a T-3 universe, L.Z.Fang, Astr.
& Astrophys. 239, 24.
176. An upper limit to quasar's peculiar velocity, L.Z.Fang, Y.Q.Chu, X.F.
Zhu and L.F. Wang, Inter. J. Mod. Phys., 5, 2993.
177. Quasar pair and quasar's peculiar velocity, L.Z.Fang, Developments in
general relativity, astrophysics and qu... 阅读全帖
p*********n
发帖数: 1159
7
来自主题: NextGeneration版 - 求个防辐射服吧
为啥到现在还有人相信这个?防辐射服不但没好处,还让baby吸收更多的辐射。
一般来说,辐射分两种,一种是 ionizing radiation,一种是electromagnetic
radiation。现在所谓的防辐射服,主要是能够防electromagnetic radiation,也就是
所谓把手机放到防辐射服里,手机没有信号。但是孕妇防辐射服并没有接地导线,所谓
的防electromagnetic radiation,也是无效的。胎儿经过母体以及厚厚的羊水保护,
生活中的electromagnetic radiation的水平早已弱化到无害水平。
但是对于ionizing radiation就出现大问题了。宇宙中最多的是ionizing radiation,
达到地球后经过大气层的过滤,处于一种弱状态,能够穿透人体,所以对人体无害。宇
航员的宇航服,并不是阻止宇宙ionizing radiation,而是将ionizing radiation过滤
到类似地球的水平,人变成透明的,ionizing radiation穿过人体。这也就是为什么宇
航员太空行走不能时间太长的原因。
本来... 阅读全帖
b***y
发帖数: 14281
8
来自主题: Military版 - 方励之的学术成就全记录
No. The search include his early works up to 1978. Here is the same list
sorted by year.
1) The Influence of Gravitation on the Vacuum State.
By Li-Zhi Fang.
Acta Phys. Sinica 27 ( 1978) 181-18.
2) THE STRUCTURE AND STABILITY OF THE ABNORMAL NEUTRON STAR.
By Li-Zhi Fang, Qin-Yue Qu, Zhen-Ru Wang, Tan Lu, Liao-Fu Luo.
Sci.Sin.22:187-198,1979.
3) Some Recent Developments in Astrophysics. (Talk).
By Li-Zhi Fang, A. Qadir, R. Ruffini.
In *Nathiagali 1980, Proceedings, Physics and Contemporary Needs... 阅读全帖
i****x
发帖数: 17565
9
来自主题: Hardware版 - 5Ghz是不是比2。4ghz的辐射更强?
懒得跟民科废话了,自己读去吧。
http://en.wikipedia.org/wiki/Ionizing_radiation
Ionizing (or ionising) radiation is radiation that carries enough energy to
liberate electrons from atoms or molecules, thereby ionizing them. Ionizing
radiation comprises subatomic particles, ions or atoms moving at
relativistic speeds, and electromagnetic waves on the short wavelength end
of the electromagnetic spectrum. Gamma rays, X-rays, and the upper vacuum
ultraviolet part of the ultraviolet spectrum are ionizing, whereas the... 阅读全帖
y*****s
发帖数: 1047
10
来自主题: Chemistry版 - 最近有质谱的组招博士后的吗
广告都多得很
Posted/Revised: 5/2/2012
Company/Institute: Pfizer Inc
Department:
Position: 2 Year Postdoctoral Fellow – Protein Quantitation in Tissues
by Mass Spectr
Job Location: Andover, MA United States
Description: 2 year Postdoctoral Fellow – Protein Quantitation in
Tissues by Mass Spectrometry and Immunoanalytical Techniques A Postdoctoral
Fellowship is available in Pfizer’s Pharmacokinetics Dynamics and
Metabolism New Biological Entities (PDM-NBE) in Andover, MA. The PDM ... 阅读全帖
h********o
发帖数: 3320
11
来自主题: Living版 - 请教,辐射的允许值
你这是说的Ionizing radiation,高压线辐射属于non-ionizing radiation,有多少危
害没有定论。
300 mrem a year是指的美国人平均一年接受的天然ionizing radiation辐射剂量。对
于职业人员,一年接受的辐射剂量上限是50 mSv,大约是5000 mrem。
B*W
发帖数: 1341
12
来自主题: NextGeneration版 - 孕妈妈上班都穿防辐射服吗
这事儿不是n多人普及过n多回了么?
The following question was answered by an expert in the appropriate field:
Q
I'm pregnant and I have to use computers for a few hours a day and I know
electric appliances also emit radiation. How harmful is all of this to me
and my baby?My friend suggests that I buy radiation protection suits.
According to their advertisements, the garments are made from a kind of
fiber interwoven with antiradiation material. Do you think it works? Should
I wear it?
问题:我现在怀孕了,每天需要用电脑几个小时,我知道电器也... 阅读全帖
B*W
发帖数: 1341
13
来自主题: NextGeneration版 - 孕妈妈上班都穿防辐射服吗
这事儿不是n多人普及过n多回了么?
The following question was answered by an expert in the appropriate field:
Q
I'm pregnant and I have to use computers for a few hours a day and I know
electric appliances also emit radiation. How harmful is all of this to me
and my baby?My friend suggests that I buy radiation protection suits.
According to their advertisements, the garments are made from a kind of
fiber interwoven with antiradiation material. Do you think it works? Should
I wear it?
问题:我现在怀孕了,每天需要用电脑几个小时,我知道电器也... 阅读全帖
g******u
发帖数: 3060
14
来自主题: LosAngeles版 - 日本机器人
Just googled and found this post.
http://www.physicsforums.com/showthread.php?t=111717
Seems like EMI does affect less than 'ionized radiaion'. And millitary does
use special semiconductor materials.
Although proper shielding should take care of this I suppose, ain't no
eletromagnetics expert myself either.
"
When gamma rays pass through a substance, they leave behind ions when they "
kick" electrons out of their bound states by interacting with the electrons.
This is why gamma and x-rays get th... 阅读全帖
b***i
发帖数: 10018
15
☆─────────────────────────────────────☆
vivil (running piggy) 于 (Fri Jun 10 15:59:50 2011, 美东) 提到:
我最近忽悠了几个local runner来做高精度骨结构扫描,看到一些有意思的结果。样本
很小,就4个(还加上我自己)。3个的trabecular bone (松质骨)结构和正常人有差异
,主要体现在有变粗变大的骨小梁,并且成片连接在一起。初步估计,在开始过长时间
,过大负荷的给予骨头Loading,unloading,造成了非常小的microfracture,
microdamage,恢复后就形成了microcallus(骨痂)。唯一一个跑完骨头一点事没有的
,当当当当,就是我们的兽人tonyprince同学。
下面按顺序是:1.vivil:我的只显示有很小的一点异常,在接近左下cortical bone(
硬质骨)的地方。
2. vivil+1,明显比我的问题要多。他头两次全马脚踝疼痛难忍,估计是有原因的。
3. simpleshue,最悲催的就是这位同学,scan结果刚出来吓... 阅读全帖
G******U
发帖数: 4211
16
Properties of Hydrogen
Hydrogen is a nonmetal. It is placed above group in the periodic table
because it has ns1 electron configuration like the alkali metals. However,
it varies greatly from the alkali metals as it forms cations (H+) more
reluctantly than the other alkali metals. Hydrogen‘s ionization energy is
1312 kJ/mol, while lithium (the alkali metal with the highest ionization
energy) has an ionization energy of 520 kJ/mol.
Because hydrogen is a nonmetal and forms H- (hydride anions), ... 阅读全帖
x******g
发帖数: 91
17
来自主题: Physics版 - 北京大学龚旗煌教授如何?
几年没更新了吧
Low Yield of Near-Zero-Momentum Electrons and Partial Atomic Stabilization
in Strong-Field Tunneling Ionization
Hong Liu, Yunquan Liu, Libin Fu, Guoguo Xin, Difa Ye, Jie Liu, X. T. He,
Yudong Yang, Xianrong Liu, Yongkai Deng, Chengyin Wu, and Qihuang Gong
Phys. Rev. Lett. 109, 093001 – Published 27 August 2012
Characteristic Spectrum of Very Low-Energy Photoelectron from Above-
Threshold Ionization in the Tunneling Regime
C. Y. Wu, Y. D. Yang, Y. Q. Liu, Q. H. Gong, M. Wu, X. Liu, X. L.... 阅读全帖
n*****1
发帖数: 1329
18
来自主题: Military版 - 强核辐射下人的瞬间感受
On May 21, 1946, with seven other colleagues watching, Slotin performed an
experiment that involved the creation of one of the first steps of a fission
reaction by placing two half-spheres of beryllium (a neutron reflector)
around a plutonium core. The experiment used the same 6.2-kilogram (13.7 lb)
plutonium core that had irradiated Harry K. Daghlian, Jr., later called the
"Demon core" for its role in the two accidents. Slotin grasped the upper
beryllium hemisphere with his left hand through a ... 阅读全帖
w*******e
发帖数: 15912
19
http://blog.voc.com.cn/blog_showone_type_blog_id_724997_p_1.htm
文/王海滨搜集整理 图片/均来自网络

[博客导读]
二十年前的今天,在美国爱荷华大学发生了中国留美物理学博士卢刚杀人事件;
三年前,以1991年卢刚事件为蓝本的电影《暗物质》在美国好来坞首映;
今天,我再回放卢刚事件,浅析电影《暗物质》 。





[卢刚事件回放]
1991年11月1日万圣节这天,中国留美学生卢刚在刚刚获得爱荷华大学物理学博士... 阅读全帖
k********k
发帖数: 5617
20
http://blog.ifeng.com/article/36639757.html
怎样看待那些死在国外的中国精英?

许锡良
2015年7月18日星期六
最近读到一篇来自加拿大华人学者、中国人民大学博士、现任加拿大政府公务员李建宏
先生的文章《梦断西方:献给惨死在西方的中国精英》(以下科称“《梦》文”,影响
很大),文中以一个个赴西方,特别是美国的中国华人精英死在美国的案例说明了一个
问题:西方很坏,美国很恐怖,那里非久留之地,奉劝各位华人还是不要前往送死为好。
然而,我第一个直觉反映是,既然西方那么可怕,那么黑暗,那为什么作者竟然安心在
加拿大当起政府公务员来,还不赶快逃离这个是非之地,他一边撰文骂着西方的社会制
度的黑暗,一边赖在加拿大政府里做着公务员,全然不怕危险,全然不顾祖国在召唤着
他。要知道,一个中国人不逃离自己的祖国那才是正常的,逃离了又骂逃往的地方很黑
暗,其实这个非常好办,那就是回到自己祖国怀抱来,没有人会拒绝你回来。圣人孔子
不是说过“危邦不入,乱邦不居”嘛。身在西方撰文骂西方,其实是一件非常容易的事
情,因为人家言论自由,即... 阅读全帖
d*b
发帖数: 21830
21
来自主题: Military版 - 破熊现在想回国都回不了了吧?
插那,所谓的“電離輻射”,是指能量损耗以 ionization的方式,所谓的ionization
是指:
1. 萝莉散射
2. pair production
3. compton
你究竟有没有学过物理?
s******r
发帖数: 5309
22
根据喂鸡百科, 卢刚生于北京市,18岁考入北京大学物理系,1984年通过CUSPEA考试
,1985年本科毕业后进入爱荷华大学物理与天文学系攻读研究生。1991年通过论文答辩
获得博士学位。他的博士论文题目是《Study of the "critical ionization velocity
" effect by particle-in-cell simulation (ionization)》,导师是本系教授克里斯
托弗·戈尔咨(Christoph K. Goertz)
北大物理系都是自命不凡的人,当年能参加卡死屁考试都是佼佼者。空间物理是北大俗
称球系的地物系的一个专业, 比物理系要低一个档次。卢刚不去学正经的物理,搞什
么混日子才学的空间物理,他和导师根本就是两类人,不出事才怪。

发帖数: 1
23
【 以下文字转载自 JobHunting 讨论区 】
发信人: ximenqin (年老色衰程序员), 信区: JobHunting
标 题: 美利坚不接受软弱,致在此自杀的中国"书本精英"们!
发信站: BBS 未名空间站 (Sun Sep 22 14:24:20 2019, 美东)
原文链接:
http://mp.weixin.qq.com/s/Y4kExxqwm3_br0kcq0pmew
顾颖琼博士友情提醒:一踏上美利坚土地的中国人都会惊讶于美国的富饶以及人民的热
情与友好,很少有人意识到美国这个社会本质上还是一个深度发达的资本主义社会。在
美国这个社会里,还是奉行着社会达尔文主义。
摘引大英百科全书,顾颖琼博士可以看见对社会达尔文主义的解释是:“社会达尔文主
义曾经被用于支持自由放任式资本主义和政治保守主义,也用于支持阶级分层的正当性
,理由是,个体之间存在所谓的‘自然的’不平等,财产多少被认为与一些优越的内在
道德品质相关,如勤劳、节俭等等,因而国家干预被认为是干扰自然过程,而无限制的
竞争和维护现状则符合生物学选择过程。穷人被认为是‘不适应环境’因而不应当被援
助,在生存... 阅读全帖
m********r
发帖数: 811
24
来自主题: WorldNews版 - lu gang
卢刚事件,是指1991年11月1日就读于美国艾奥瓦大学的中国博士留学生卢刚在校园中
射杀数人的枪击事件。该事件在当时曾震惊中美两国,也引起了一场关于中国教育弊端
的讨论。
目录
[隐藏]
* 1 卢刚简历
* 2 经过
* 3 结果
* 4 各方反应
* 5 相关文学影视作品
* 6 外部链接
[编辑] 卢刚简历
卢刚生于北京市,18岁考入北京大学物理系,1984年通过CUSPEA考试,1985年本科毕业
后进入艾奥瓦大学物理与天文学系攻读研究生。1991年通过口试获得博士学位。他的博
士论文题目是《Study of the "critical ionization velocity" effect by particle
-in-cell simulation (ionization)》,导师是本系教授克里斯托弗·戈尔咨(
Christoph K. Goertz)
[编辑] 经过
1991年11月1日下午三点半左右,卢刚进入了正在进行专题研讨会的艾奥瓦大学凡·艾
伦物理系大楼(Van Allen Hall)三楼的309室,在旁听约五分钟
s***e
发帖数: 7166
25
来自主题: Automobile版 - 洗车的去离子水设备好用吗?
比如这个:
CR SPOTLESS De-Ionizing Spotless Water System
Spot-free Rinse System, No Drying Required, Produces 100% Pure,
Mineral-free De-ionized Water
貌似和我上班用的去离子水设备差不多……
i****x
发帖数: 17565
26
来自主题: Automobile版 - 人太认真好学太累了。。。。
U want me to believe u as an eng phd don't know Planck equation? Don't know
about ionizing radiation and non-ionizing radiation? As a social science
folk I had enough fun explaining torque is not a unit of work to a self
claimed science/eng folk. Don't get me started again.

这才是个像样的回答。比起其他几个只会骂街的好多了。不过对于国内工厂的生产条件
和劳动保护,似乎向来不是那么受到重视。如果长期在电解长工作而没有额外健康问题
,那么电机这一点应该是影........
★ Sent from iPhone App: iReader Mitbbs Lite 7.52
g*****9
发帖数: 4125
27
来自主题: Living版 - 请问两个仪器, 谢谢!

What kind of radiation are you checking?
Ionizing radiation include:
Alpha radiation
Beta(+/-) radiation
Gamma radiation
Non-ionizing radiation include:
Neutron radiation
Electromagnetic radiation
Light radiation
Thermal radiation
Black-body radiation

Continuous radon monitor
g*q
发帖数: 26623
28
什么reading?
Ionizing radiation? non-ionizing radiation? 磁场?电场?

.
b*p
发帖数: 234
29
我儿子两岁左右进ER也被逼照了一次x-ray, 这是第二次了,两次肺上都没有问题。
google了一下Ionizing & Non-Ionizing Radiation的差别,x-ray真的很
让人担心,这跟背景辐射是不同的。
t*******r
发帖数: 22634
30
iphone 是 non-ionization radiation,石头的是 ionization radiation,
当然不用过分担心。
l**********g
发帖数: 426
31
来自主题: WaterWorld版 - zz华尔街中国人不抱团儿
卢刚事件,是指1991年11月1日就读于美国艾奥瓦大学的中国博士留学生卢刚在校园中
射杀数人的枪击事件。该事件在当时曾震惊中美两国,也引起了一场关于中国教育弊端
的讨论。
目录 [隐藏]
1 卢刚简历
2 经过
3 结果
4 各方反应
5 外部链接
6 参考文献
[编辑]卢刚简历
卢刚生于北京市,18岁考入北京大学物理系,1984年通过CUSPEA考试,1985年本科毕业
后进入艾奥瓦大学物理与天文学系攻读研究生。1991年通过口试获得博士学位。他的博
士论文题目是《Study of the "critical ionization velocity" effect by particle
-in-cell simulation (ionization)》,导师是本系教授克里斯托弗·戈尔咨(
Christoph K. Goertz)
[编辑]经过
1991年11月1日下午三点半左右,卢刚进入了正在进行专题研讨会的艾奥瓦大学凡·艾
伦物理系大楼(Van Allen Hall)三楼的309室,在旁听约五分钟后,他突然拔出左轮
手枪开枪射击,他首先击中他的博士研究生导师,47岁的戈尔咨教授,... 阅读全帖
h******n
发帖数: 493
32
来自主题: XMU版 - question for hooligan
There are certainly different effects on different types
of interactions. Electrostatic interactions are usually
strengthen in the gas phase, while the effects on H-bond
and hydrophobic interactions are not clear. I can't really
say too much about this, since I am not knowledged enough.:)
References:
1) Loo, J. A. (1997)
Studying noncovalent protein complexes by
electrospray ionization mass spectrometry.
Mass Spectrom Rev 16, 1-23
2) Loo, J. A. (2000)
Electrospray ionization mass spectrometry: a
I******i
发帖数: 203
33
来自主题: Biology版 - 癌症治疗终极攻略
哈哈哈哈
“你可以去购买各种活力水机(Water Vitalizer),它可以帮助生成结构化水(
Structured Water)来饮用。结构化水可以有效帮助血液吸收更多的氧气,因为血液中
90%的含量是水分。血液中的氧气越多,供给身体细胞的氧气就越多。我们还可以去买
水离子化设备,电解水机(Water Ionizer),可以把饮用水电解成酸性(Acidic)和碱性(
Alkaline)两部分。如果你只饮用碱性部分,可以帮助恢复身体的pH平衡,很多时候仅
仅恢复pH平衡就可以足够缓解癌症。”
结构化水。。。
电解水机(Water Ionizer)。。。
I******i
发帖数: 203
34
来自主题: Biology版 - 癌症治疗终极攻略
哈哈哈哈
“你可以去购买各种活力水机(Water Vitalizer),它可以帮助生成结构化水(
Structured Water)来饮用。结构化水可以有效帮助血液吸收更多的氧气,因为血液中
90%的含量是水分。血液中的氧气越多,供给身体细胞的氧气就越多。我们还可以去买
水离子化设备,电解水机(Water Ionizer),可以把饮用水电解成酸性(Acidic)和碱性(
Alkaline)两部分。如果你只饮用碱性部分,可以帮助恢复身体的pH平衡,很多时候仅
仅恢复pH平衡就可以足够缓解癌症。”
结构化水。。。
电解水机(Water Ionizer)。。。
a****g
发帖数: 62
35
来自主题: Chemistry版 - 问一个MALDI TOF的问题
First of all, not all polymer can be ionized by MALDI. The polymer has to
contain conjugated structure or heter-atoms. Even if the polymer is
ionizable, mass discrimination can be a issue if molecular weight
distribution is too wide.
Why don't you use GPC instead?
c*******e
发帖数: 170
36
来自主题: Chemistry版 - 求教:氮气能解离成氮原子吗?
From my experience, I dont think it is possible that the jet will induce the
dissociation of N2. You said there is resonant ionization by laser. I
would ask what kind of you are using, especially for the pulse duration and
wavelength.
Let's consider this problem in two ways:
1. Suppose what you have seen is really Nitrogen atomic ion. The most
likely mechanism should be Nitrogen molecule absorbs the photon(s) to
dissociation, and Nitrogen atom is ionized by other photons. However, the
highe
x****o
发帖数: 60
37
来自主题: Chemistry版 - 问个LC/MS/MS定量的问题
I have a feeling that matrix effect should be concentration independent.
Ionization enhancement or supression should be the same, e.g. -25% or +25%.
Thus, curve bending can not be explained.pH is too strong, which might make
the ionization efficiency not consistent across assay range.
c******m
发帖数: 884
38
来自主题: Chemistry版 - pKa 问题,请教各位大牛
Thank you for the reply. Do you mean triethylamine for TEA? If so, I didnot
use any TEA in the previous wash.
The ion exchange (IX) solid phase (SP) contains a linker-piperazine with pKa
of 6, so I load the orotic acid (ORA, pKa1=2.8) with a pH 4.4 (half of 2.8+
6) solution to make sure both SP and ORA are ionized. Then I use 2%Formic
Acid/water (pH=2) to wash (should not elute any ORA out), and then use NH4OH
in MeOH/ACN to elute ORA. But the result shows the acidic wash step elute a
lot ORA. S... 阅读全帖
s*********i
发帖数: 45
39
来自主题: Chemistry版 - 真心求助几道本科无机试题
本人学有机的,对学生的无机问题一窍不通,哪位大虾帮帮忙,万分感谢!
Problem Set
1. We can study trends in effective nuclear charge using X-ray photoemission
spectroscopy (XPS),which measures the energy required to ionize an atom.
The X-radiation is energetic enough to excite electrons at all levels (even
core levels) so this technique can probe electrons in specific orbitals.In
an XPS experiment, C atoms reacted with a surface, forming C–Si bonds.
Before the reaction, the ionization energy was 36.7 eV; after the reaction,
it shi... 阅读全帖
b*******g
发帖数: 1309
40
来自主题: Chemistry版 - 请教质谱做SRM的离子利用效率
你这个应该叫transmission efficiency,QQQ,从形成离子进入Q1开始算,到Q3,效率
超过90%,好像在95%以上,所以要提高LOD必须在ionization source 跟Q0上下功夫。
举个例子AB Sciex 的6500跟5500 的区别就是source enhance 2倍LOD,Q0(Qjet)
enhance 2倍2LOD,共计4倍LOD
QTOF 的ion transmission主要是损失在 flight 过程中,另外TOF的pulse frequency
并不慢,大部分仪器都在 20kHz 左右,就是0.05ms一次。
速度慢在仪器跟电脑之间的传输,没想到吧,每个TOF的spectrum在被digitization过
后从instrument到电脑需要的时间在ms ,这段时间TOF只能idle等digitizer
clearance
所以QTOF效率取决于duty cycle time跟飞行过程中的离子损失。QQQ现在的duty cycle

般可以到2-5ms per MRM,但是QTOF最快能到10ms,一般只能到50ms。意味着同样的时... 阅读全帖
z*****n
发帖数: 7639
41
So far, there is no result to proof that RF
wave can ionize molecules.
ONLY at the extremely high frequencies such as X-rays, electromagnetic parti
cles have sufficient energy to break chemical bonds (ionization).
m********r
发帖数: 127
42
来自主题: Pharmaceutical版 - LC experts: pls come in
Oh, btw, is ur sample ionizable? What's the pka? Maybe try 20mM phosphate or
acetate buffer as mobile phase?
I had some bad memory of water make my ionizable compounds silly in HPLC.
U*E
发帖数: 3620
43
http://io9.com/mechanic-accused-of-inventing-a-death-ray-for-is
http://img.gawkerassets.com/img/18rbluohnpgmxjpg/k-bigpic.jpg" onload="adjustimg(this)">
A mechanic who worked at General Electric in New York spent the past
several years perfecting a deadly, truck-mounted radiation weapon. According
to the FBI, he tried to sell it to some Jews in his area, whom he figured
could hand it over to Israel. Failing that, he tried to sell it to some
friends in the KKK.
Glendon Scott Crawford is... 阅读全帖
i***s
发帖数: 39120
44
美国联邦通信委员会(FCC)计划调查其先前制定的手机辐射最高标准能否保证消费者的健康免受辐射干扰。现行标准是FCC在1996年根据手机散热量而制定出来的。
FCC女新闻发言人Tammy Sun在一封通过电子邮件发表的声明中表示,FCC主席朱利叶斯-格纳考斯基(Julius Genachowski)向该委员会其他委员散发了一份提案,要求各位委员批准对手机辐射标准展开正式调查。但这份提案并未涉及具体的执行标准。
Tammy Sun在声明中指出:“我们今天采取的措施只是对执行标准的例行检查。我们相信,此前制定的手机辐射最高标准不会给消费者带来任何威胁。”
电信产业咨询服务公司Ovum的亚太咨询主管CW Cheung表示:“任何标准上的变化都将给手机生产商带来影响。由于多数手机生产商的总部都不在美国本土,因此这可能还会引发贸易纠纷。”
根据市场研究机构Strategy Analytics公布的统计数字显示,今年第一季度,韩国三星电子成为全球最大的手机生产商,芬兰诺基亚位居次席,而苹果则位列第三。
恐伤及大脑
美国国立卫生研究院(National Institutes of Health, NI... 阅读全帖
c*****a
发帖数: 1238
45
HAARP to understand the technology of reversed piezoelectric effect in which
earth can tremble when energy is applied to ionosphere. Scientific
references will be underlining this further in this post:
- US Patent 4686605 - Method and apparatus for altering a region in the
earth's atmosphere, ionosphere, and/or magnetosphere
www.patentstorm.us/patents/4686605/fulltext.html
- US Patent 4999637 - Creation of artificial ionization clouds above the
earth
www.patentstorm.us/patents/4999637/fulltext.h
i**b
发帖数: 918
46
childhood leukemia成因非常的复杂。一般来说病毒感染、接触致突变药剂和ionizing
radiation都可以导致。
小儿白血病发病率的增高,一部分原因是由于环境污染,还有一部分也因为医疗条件的
改善,白血病的诊断率增高导致。

元。
z**n
发帖数: 22303
47
The study, called REFLEX, which stands for Risk Evaluation of Potential
Environmental Hazards from Low Energy Electromagnetic Field Exposure Using
Sensitive in vitro Methods, was a four-year, $4 million-plus research
project majority-funded by the European Union. Results of the research
project, which ended in May, were published on the Internet earlier this
month.
"We have proven that electromagnetic fields--in high and low frequencies--
damage cells in individual cell systems," says Franz Adlk... 阅读全帖
Z**S
发帖数: 1211
48
It is not the cancer cells in the food one needs to worry about, it is the
radioactive elements inside the food. They will ionize your cells and
induce cancer in you as well.
d*b
发帖数: 21830
49
无线电信号又不是 ionize radiation, 大汽中基本没有吸收,你说的所谓信号衰减跟
距离有关,那是指点源,点源是按1/R^2衰减,parallel beam没这个。
找本天线原理去看看吧
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