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全部话题 - 话题: spectrometer
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E****a
发帖数: 118
1
来自主题: Chemistry版 - 求转让审稿机会
如果大牛们的审稿够的话,请转让审稿机会给我吧(审稿邮箱:fawa5960@jila.
colorado.edu), 影响因子不限,国内外杂志都可以。
本人第二年博后了(一直在美国),我的方向是分子光谱(红外可见光)研究,但
审稿物理化学方向都可以,读博士之前也有一些催化方向的经验,以下是自己的简单介
绍:
I received my Bachelor’s of Science degree in Chemical Physics from
University of Science and Technology of China in 2008. During this I had two
year research experience on surface science and catalysis of model
catalytic systems. my undergraduate thesis was “Synthesis and Catalysis
study of N-doped TiO2 in nano-scale”. I completed my PhD de... 阅读全帖
p*****t
发帖数: 19
2
A postdoctoral position is available to work on drug discovery in the
Department of Chemistry and Biochemistry and Milwaukee Institute of Drug
Discovery at the University of Wisconsin-Milwaukee. The research will focus
on synthesizing small molecules and studying their biological properties,
including testing anticancer activity both in vitro and in vivo, figuring
out the mechanism of function (such as interactions with DNA, DNA damage,
cell damage, PK and stability study, etc.). The lab has acc... 阅读全帖
e****2
发帖数: 2723
3
流浪汉一样的临工 我为你悲哀

focus
equipment
spectrometers,
with
k****o
发帖数: 728
4
来自主题: Chemistry版 - 请教Q TOF维护问题
谁熟悉Waters Q TOF质谱的维护?最近接手一个老仪器Micromass Q-TOF Ultima API
Mass Spectrometer. 最近发现TOF Penning逐渐升高,从最初的3.0 e-7(听说不能超
过3.5e-7),逐渐升到4.5 e-7.如果仪器处于stand by mode,TOF penning能稍微低点
但也是高于3.5e-7。这个值似乎与mass accuracy 有关。发现超过4e-7后,即便是刚
calibrate后很大的protein(40-100 kDa) mass error也能达到8-15 Da(而小protein
还是很准的)。而前段时间TOF Penning正常时就没有这个问题,mass error对100 kDa
的protein error只有4 Da. 另外,Turbo speeds里面TOF Speed那一项在98-100%之间
徘徊,而过去能一直保持在100%。不知道有没有问题。有没有建议怎么tune一下?
f********e
发帖数: 2194
5
来自主题: Chemistry版 - Papers help
Can you please help me with the following articles?
[email protected]/* */
Thank you!
Bioanalysis. 2013 May;5(10):1249-67. doi: 10.4155/bio.13.93.
Performance assessment of microflow LC combined with high-resolution MS in
bioanalysis.
Hongxia Wang & Patrick Bennett
http://www.future-science.com/doi/abs/10.4155/bio.13.93?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%3dpubmed
Bioanalysis. 2014 Aug;6(16):2159-70. doi: 10.4155/bio.14.115.
Quantitative proteomics using the high... 阅读全帖
B8
发帖数: 92
6
The Department of Environmental Sciences and Engineering at Gillings School
of GlobalPublic Health, University of North Carolina at Chapel Hill has a
postdoc opening. We are looking for a self-motivated person to conduct omics
profiling to understand the interactions between the gut microbiome and
diseases/environmental exposures. Our lab has dedicated high-end mass
spectrometers, including Q-Exactive HF Orbitrap and 6550 Q-TOF.
A PhD degree or solid training in analytical chemistry or related f... 阅读全帖
M***a
发帖数: 175
7
应该不是说必须TE,而是你的SOA在TE偏振上能够获得最大增益。
偏振的信息可以通过测试不同偏振方向上的光场强度获得。用polarization
controller加spectrometer就可以测。
q*********n
发帖数: 103
8

电压电流乘出来的electrical power
optical power要用powermeter或其他的spectrometer测
是吧?
W*********m
发帖数: 17
9
来自主题: GeoSpace版 - paper help!
Journal:Nuclear Instruments and Methods in Physics Research Section A:
Accelerators, Spectrometers, Detectors and Associated Equipment
Volume 338, Issues 2-3, 15 January 1994, Pages 560-567
Title: Determination of natural 32P and 33P in rainwater, marine particles
and plankton by low-level beta counting
N.A. Waser, 1, a, A.P. Fleera, T.R. Hammara, K.O. Buesselera and M.P. Bacona
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TJM-473FMY7-1KF&_user=10&_coverDate=01%2F15%2F1994&_rdoc=35
a*q
发帖数: 2109
10
来自主题: Macromolecules版 - [转载] Spectroscopy Question
【 以下文字转载自 Chemistry 讨论区,原文如下 】
发信人: abq (I Love JUNE), 信区: Chemistry
标 题: Spectroscopy Question
发信站: The unknown SPACE (Tue Aug 27 19:20:22 2002) WWW-POST
My FTIR spectrometer has a external sampling compartment.
But when I collect the spectra, they have spikes all over the 4000-400
wevemunber region. Equally spaced by about 200 wavenumbers.
There is nothing but three KBr plates in the beam path.
(These KBr plates are parallel to each other, and they all perpendicurlar to
the IR beam.)
What wou
s****n
发帖数: 212
11
1, what effect will using an 900MHz NMR rather than a 300MHz NMR spectrometer
have on the linewidths of a molecule with a molecular weightof (1)1000;
(2)10,000;
Why?
2,Explain why small molecules(MW<500 Da)GENERALLY HAVE more narrow resonances
than large molecules(MW>3000 Da)?
3,Explain why moderately large molecules(MW in a range of
1000-10,000)GENERALLY HAVE more narrow resonances than very large
molecules(MW>100,000 Da)
非常谢谢!
c*******n
发帖数: 1648
12
偶去洗耳朵先。你们关门,放CPMAS!

spectrometer
resonances
C***S
发帖数: 175
13
I am here in LA for APS meeting.
solution NMR is slightly different from solid state NMR.
the basic is relaxation depends not only on the dynamics/motion of the
molecules but also field depend.
Generally, small molecules have long relaxation time and high field will
reduce the relaxation time.
The linewith depends intrinsically on the chemical conformation, but also
depends on the external field.
so, it is always a compromise to select high or low field spectrometer.
1) since the relaxation is n
y***n
发帖数: 28
14
Physical Chemistry Postdoc Research Opportunity at Boston University
 
Xin Chen’s research group, newly-founded at Boston University, Department
of Chemistry in 2011, is seeking a postdoctoral researcher (or a visiting
scholar) with experience in ultrafast laser spectroscopy and nonlinear
optics.  His/her major responsibility would be to set up and carry
experiments using a board-band vibrational sum-frequency spectrometer and
imaging system.  Candidates experienced in nonlinear v... 阅读全帖
o********e
发帖数: 34
15
【 以下文字转载自 Physics 讨论区 】
发信人: olivertree (Life is good), 信区: Physics
标 题: research scientist position at NIST (open for all nationalities)
发信站: BBS 未名空间站 (Mon Mar 17 16:54:23 2014, 美东)
The Macromolecular and Microstructure Sciences (MMS) team at the NIST Center
for Neutron Research (NCNR) is seeking a research scientist with a strong
record of creativity and achievement in any area of nano and microscale
science or instrumentation science. The candidate should complement and
expand current scien... 阅读全帖
l******u
发帖数: 2314
16
我那个贴都删掉了还被你引出来。。。
我看错了,以为问的是NIR Absorption;结果一看,xiaoyi2008问的是NIR FLSC。
Shimadzu的Absorption spectrometers确实不错。
l*******s
发帖数: 65
17
先测fuse quartz, 再放ZnO上去测
m*******e
发帖数: 119
18
你在测两片和三片合在一起时, reference 也是两片和三片slides合在一起吗?
如果不是,你的光谱会有一些周期性震荡。slides其实是一个很弱的Febry-Perot 光学
腔。如果你的参考光路和测量光路的slides厚度一样,可以抵消光干涉的影响。
m******e
发帖数: 432
19
谢谢两位的回复!我首先测量的所有fused quartz的吸收(空气是reference),发现
它们是一样的。后来做的时候,我用空的fused quartz做reference, 有ZnO的做样品.
测量两片或三片的时候,也的确是用也是两片和三片slides合在一起做reference.
我会重复再做几遍, 再看看!
m******e
发帖数: 432
20
会不会是因为fused quartz本身的吸收太强(300nm左右及以下)?虽然不同fused
quartz本身的吸收几乎相同,但是它们之间的细微差别对于ZnO来说太大,从而产生极
大的干扰。
m*******e
发帖数: 119
21
你说的很有可能。slides比你的ZnO薄膜要厚很多,300nm 以下的测量可能不准确。
c*s
发帖数: 2145
22
会不会有散射啊,来自大的纳米颗粒以及在石英片之间的空气气泡
m******e
发帖数: 432
23
利用测吸收来测量带宽会不会对仪器有些要求?一般的仪器可否?我用的仪器就是平时
用来测量有机染料吸收的仪器,只不过没有用cuvet罢了。
A***N
发帖数: 219
24
DXR SmartRaman Spectrometer
The sales man asked for $20K!!!
That was too much!!!
s*****y
发帖数: 4595
25
来自主题: Pharmaceutical版 - 有熟悉varian mass spectrometer的么?
他们这个号称multi mode ionization,是怎么回事?ESI, APCI同时运作?谁能具体讲
讲?谢谢!
w********g
发帖数: 447
26
来自主题: Pharmaceutical版 - 有熟悉varian mass spectrometer的么?
angilent的那个是ESI和APCI一起,angilent主页里面有个video介绍这个

他们这个号称multi mode ionization,是怎么回事?ESI, APCI同时运作?谁能具体讲
讲?谢谢!
E***n
发帖数: 308
27
来自主题: Pharmaceutical版 - 有熟悉varian mass spectrometer的么?
ESi and APCI switch, not same time. I guess that is why the flow rate has to
be slow, or else data will be lost.
w********g
发帖数: 447
E***n
发帖数: 308
29
来自主题: Pharmaceutical版 - 有熟悉varian mass spectrometer的么?
ESI and APCI under two modes negative/postive are not same time.

to
R*******1
发帖数: 6
30
Ad Description for BS/MS Sr Associate Scientist
Responsibilities:
• Work within the Analytical Protein Chemistry area to provide
analytical support for novel peptide and protein therapeutics in pre-
clinical and clinical development.
• Primary responsibilities include the identification and
characterization of post-translational modifications in protein therapeutic
candidates, using state of the art separations technology and mass
spectrometry instrumentation, with an emphasis ... 阅读全帖
d**********8
发帖数: 15
31
来自主题: Pharmaceutical版 - 求内推,求指教
找了大半年工作找的有点灰心,求各位前辈内推和指教,本人生物工程fresh phd刚毕
业,主要做cell culture, cell based assay, cellular uptake of nanoparticles,
以及对细胞施加外力研究其对细胞的影响,博士期间也做过将近半年的Internship,在
一家仿制药公司做小分子方面药物分析,掌握waters/agilent HPLC, UV
spectrometer, 以及drug dissolution,求指导求推荐工作机会。在此感谢!
y***n
发帖数: 28
32
Physical Chemistry Postdoc Research Opportunity at Boston University
 
Xin Chen’s research group, newly-founded at Boston University, Department
of Chemistry in 2011, is seeking a postdoctoral researcher (or a visiting
scholar) with experience in ultrafast laser spectroscopy and nonlinear
optics.  His/her major responsibility would be to set up and carry
experiments using a board-band vibrational sum-frequency spectrometer and
imaging system.  Candidates experienced in nonlinear v... 阅读全帖
E*******1
发帖数: 3464
33
来自主题: Physics版 - 请教一个raman的问题
Raman Shift就是phonon的能量,因为spectrometer记录了scattered light的能量,E_
incident light- E_scattered light == E_phonon,理论上其实很难,民科的解释很
简单,wiki就行了
一般谱单位都是cm-1,换成THz的话就是乘上光速(3*10^10cm/s)
c********t
发帖数: 351
34
Postdoctoral position in the optical spectroscopies group at the University
of Tennessee
The optical spectroscopies group at the University of Tennessee anticipates
an opening for a postdoctoral researcher starting in late 2012/early 2013.
Our program features a series of unique
spectrometers and access to a wide array of chemical and physical tuning
techniques: www.chem.utk.edu/~musfeldt/. Current research areas include: (i)
optical properties of polar oxides, (ii) optical properties of molecul... 阅读全帖
a****o
发帖数: 298
35
来自主题: Physics版 - 曼哈顿/Queens什么学校有raman?
什么学校有raman,UV Visible Spectrometer?
谢谢~
w********o
发帖数: 10088
36
搞光电你怎么也得搞到PL,买几个laser和spectrometer吧
找filler的话,买几个积分球就行了。剩下的那些透镜,fiber什么的你看着办
你列出来的那几个买完了估计也不剩啥钱了
话说你ld到底干过光电没有啊
p*****0
发帖数: 1100
37
就是没有做过光电才发帖问的啊!
PL我上面也列出来了,就是photoluminescece吧?laser和spectrometer是包括在一整
套的PL设备里的吧?以为国内有些仪器公司,给出的是整套的PL设备。
不知道如果买PL的话,需不需要买EL(electroluminescece)和CL(
cathodolunimescence)了?
filler和fiber是不是都是小器件?
P*****s
发帖数: 375
38
来自主题: Science版 - [转载] 荧光的过程(3)
【 以下文字转载自 Whisper 讨论区 】
【 原文由 physics 所发表 】
关于上述荧光机制的几个补充问题:
A. 事实上的荧光分子有一系列的分子能级,实际情况不是三能级那么简单。这也就是说,
excitation激发光和emission荧光的光谱峰都有个很大的宽度,因为根据原子
物理,低温下的单个能级在高温下会成为一组紧密相邻的能级(即能带)。
B. 光谱的测量不但可以用spectrometer测量bulk sample,还可以配合显微镜观察具体的
样品中哪一部分出现或消失了荧光,即荧光显微镜。生物学上,将荧光分子事先与
要观察的生物大分子结合(binding),然后将该大分子加入到生物反应过程中,就可以
跟踪观察该大分子的变化。(典型例子:GFP)
C. 实际应用时,除了要考虑该荧光剂是否能和生物大分子有效结合,结合是否没有影响
该生物大分子原有的生物功能,以及荧光效率及波长是否有利观测,还有个重要的
问题是photobleaching:在强光或长时间照射下荧光分子可能会发生不可逆转的
破坏性光化学反应,失去荧光功能。为此
w***o
发帖数: 151
39
来自主题: DataSciences版 - Looking for a programmer NYC
Job description: We are looking for a part-time/temporary data scientist/
programmer to join our NIH-funded project for analysis and extraction of RNA
sequence information from pools of digital numbers (currently in excel
files) collected from liquid chromatography - mass spectrometers.
Qualifications:
excellent in Excel
excellent in programming
relevant experience in data analysis of DNA/RNA sequencing and
algorithm development
Experience in nucleic acid chemistry and mass spectrometry-based
se... 阅读全帖
s******s
发帖数: 1584
40
昨天去面个政府工,medical technologist III 的职位。楼主是生物专业的万年
薄厚,能申到这个职位个人感觉纯属巧合,当然相似的地方是现在的工作用到Mass
Spectrometer,之后的也是,就只有这一个关键词对上了
政府工的面试是非常standard. 问题是HR设计好的,每个Candidate都一样,面试
的人就是负责把题目念一遍。流程是先发给你上面有题目的3张纸,一共9条题目,有半
个小时想怎么答,他们过半个小时来,念题目,我答,他们把我讲的话一个字不漏的抄
下来说是这样以后有据可查(我非常惊讶他们不弄个录音机啥的,因为我跟面试的两个
人几乎没有任何交流,他们只负责念题加抄写,最后洋洋洒洒抄了三大张)以下是题目:
题目是不可以外漏的,不要转载啊!!!!
behavior questions:
1) How to deal with a difficult co-worker?
2) How to deal with a stressful situation?
General:
1) what is the most important t... 阅读全帖
m****g
发帖数: 530
41
来自主题: _Harvard_Medical_School版 - 质谱分析法将加快新药的鉴定速度
加州大学William Gerwick,等研究人员最近开发出一种新的研究工具,能够快速对环形
非核糖多肽(ring-shaped
nonribosomal peptides ,NRPs)定性,由于NRPs是一类存在于自然界中的重要药物,
因此,该技术的开发将有利于科学
家快速鉴定从自然界获取的某些药品是否是新药或是具有开发前景的高分子药用材料。
NRPs在细菌中起着化学防御的作用,从青霉素诞生,NRPs就起着无可比拟的药理学功效
:大多数的抗癌药物或抗微生物试
剂都是天然产物及其衍生物。
该课题组开发的这种新的质谱(mass spectrometers)分析方法能够快速扫描NRPs的各
个小多肽片段,从而识别哪些是
新药,那些是已开发过的药物。第一步,通过计算机将各个多肽片段组合,以检测组成
的环状NRPs的化学结构,这一步称
为“NRPs从头测序法(De Novo sequencing of NRPs)”。第二步,研究人员利用“去
重复(dereplication)”工具,将第
一步中获得的NRPs的化学结构与其他相关的物质的质谱信息进行比较。通过这两个步骤
,研究人员能够对所研究的
b****y
发帖数: 103
42
来自主题: _Optics版 - 支持支持
co support
alligator, sounds like you have done a lot of remote sensing work.
so if I want to get into a program dedicated to remote sensing/hyper
spectrum imaging, any recommendation about the university/program?
The stuff I have been working with
optical data storage
adaptive optics
near infared spectrometer
a little bit lens design
mid IR imaging
compressive sensing
I'd love to get my hands on in the future
remote sensing
hyper-spectrum imaging
imaging processing
s****i
发帖数: 72
43
我们做考古的,想用高科技看看磁器和gun flint的成分
不知道靠谱不靠谱
g*******n
发帖数: 12458
44
这么大的东西怎么可能portable呢.我想UVA or UMCP实验室应该都有这个吧.
s****i
发帖数: 72
g*******n
发帖数: 12458
46
我教你一招,上UVA or UMCP or any other university in DC area的学校网站,找
materials science or chemical engineering系,看他们各个faculty的主页,一般有
research facility这一栏,会介绍他们有哪些仪器。或者直接发email给任何一个老板
手下的中国人,一般都会乐意回答你问题的。其实我怀疑象NIST/NIH这种财大气粗的政
府部门设备更全更新,也可以找人打听打听。
c********2
发帖数: 361
47
UMCP chemistry department X-ray facility may have it. Though I doubt they
have portable one.
f*r
发帖数: 3968
48
来自主题: _Astronomy版 - 用拉曼效应寻觅生命的化学指纹
用拉曼效应寻觅生命的化学指纹
著: Lee Siegel (美国宇航局天体生命研究所)译:Alex
大概是在2008年,火星上的一个探测车的将把它的机械臂对向一块岩石。在臂端的一
个探测器会扫描这块岩石, 不断地用极细的绿或紫外激光束轰击它的表面。
当激光射到岩石,即会被随机地散射到四面八方。大多数光线会保持原有的颜色,而
很少的一部分则将变为其他颜色,这就是拉曼效应。这点细微的变化就可以告诉我们岩石
上是否有生命的迹象,无论是微生物还是火星古生命残留下来的有机遗骸。通过它,我们
也能了解到火星是否曾经拥有适宜生命存活的条件。
在更远的将来,一个星际“潜艇”将潜入木卫欧罗巴的汪洋,并用拉曼探测器分析海
水中的矿物质,以寻找在海底热喷泉中可能存活的生命。
随着设备的小型化,科学家们正在研制可以发射到火星或欧罗巴上的拉曼分光仪。他
们希望携带着拉曼设备的飞船能在2007进军火星。
一、拉曼分光仪--极具前景的仪器
绿-激光火星微光束拉曼分光仪(Mars Microbeam Raman Spectrometer
)(http://epsc.wustl.
f*r
发帖数: 3968
49
来自主题: _Astronomy版 - 火热的相机—冰冷的复苏
火热的相机—冰冷的复苏
著:Robert Irion 译:bood
哈勃望远镜下星期的维修工作会使天文学家们兴高采烈起来。宇航员不仅会给哈勃装
上一个优秀的新照相仪,他们还会修复一个因爆炸而提前关闭的旧设备。
准备修理的设备是近红外照相仪和多体分光仪(Near-Infrared Camera and
Multi-Object Spectrometer,NICMOS)。NICMOS安装于1997年2月,它能够窥视那些因尘
埃遮挡而不为哈勃所察觉的天体。然而,一次偶然的短路事故使这个照相仪的固态氮制冷
剂发生汽化,于是NICMOS在1999年的1月就停止了运转。
这个勇敢的修理工作就像是在大学宿舍里修理一个小型制冷机。“在轨道上重新注入
氮气可不是简单的事情,所以我们想出了使照相仪机械制冷的方法。”参与这个工程的一
位科学家Ed Cheng这样说,他是NASA在Maryland州的戈达德航天中心(Goddard Space
Flight Center)的工作人员。由New Hampshire州Hanover地区的Creare公司制造的制冷
设备质量仅90克,它由一个转速为7000转/秒的半
j*c
发帖数: 97
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来自主题: _Astronomy版 - CHIPS--satellite to study space in space
Keith Koehler
Wallops Flight Facility, Va. October 17, 2002
K***************[email protected]
Phone: 757-824-1579
RELEASE: 02-149
SATELLITE TO STUDY THE SPACE IN SPACE NEARS LAUNCH
A satellite that will examine the "empty" space between stars
has reached a milestone towards a December launch with its
arrival this week at the Vandenberg Air Force Base, Calif.,
for integration with the launch vehicle.
The Cosmic Hot Interstellar Plasma Spectrometer (CHIPS)
satellite, the first in NASA's Unive
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