Recent content by evidenso

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    Purpose of Entrance Slit in Spectrometer: Rgds Evidenso

    Hi Can anyone tell me the purpose of a entrance slit in a dispersive spectrometer. What is it good for? I guess it will create a single slit diffraction pattern. Why will this make the resolution better, instead of just colliminate the beam? Will the slit do some kind of Fourier filtering...
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    What is the difference between RMSE and standard deviation?

    hello can anyone explain what the difference is between RMSE and standard deviation. I am using RMSE in multivariate analysis but is it just the standard dev. why another name?
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    MATLAB Adding Signal and Shot Noise in MATLAB - MB's Question

    No home assignment. I have to use it for investigating whether Raman SSRS degrades SNR :) but that's a whole other story for physicsians I have to know if adding 2 noise sources gives more noise? let's say it is gaussian noise and I have 2 vectors with signal1 + noise1 and signal2+noise2...
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    MATLAB Adding Signal and Shot Noise in MATLAB - MB's Question

    hello well I have 2 vectors in MATLAB each representing a signal+shot noise. I have to add them. Can anyone tell me what the signal noise ratio will be when they are added? thanks MB
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    Why does signal yield increase with shorter wavelength in Raman spectroscopy?

    This is a basic non QM practical guide "Raman Spectroscopy in Chemical Analysis wiley 2000" Raman intensity varies with fourth power of frequency and you know that c=\lambda*frequency This is explained in "Raman Spectroscopy in Chemical Analysis wiley 2000" It's because there is a factor...
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    Why does signal yield increase with shorter wavelength in Raman spectroscopy?

    Sorry to disapoint ya. Raman intensity DO varies with the fourth power of the observed frequency for normal Raman scattering, which, in turn, depends on laser frequency. It can be derived from the classical treatment of scattering from an oscillating induced dipole, with the intensity...
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    Why does signal yield increase with shorter wavelength in Raman spectroscopy?

    well the Raman process DO depent much on wavelengt (to the fourth power). And it's well understood. The fourth power can appear through a lengthy derivation using timedependent pertubation theory, second quantization of E-field and derivation of interaction between charges and E-field. You...
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    Need Help Understanding Closure Rule

    well it's stated as this \sum{|r><r|}=I I do understand a lot of QM but why is it gived as a summed product. how does bracket notation work in the sense?. what is the difference to \sum{<r|r>}. I can't picture it in my head.
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    Need Help Understanding Closure Rule

    hey Im having problem about closure rule can anyone explain the closure rule? why does it gives one mads
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    Does Averaging Spectra Improve Noise in Raman Spectroscopy?

    Hello Im doing som Raman spectroscopy of som substances. I know the signal/noise scales with the root of integrationtime. But can anyone tell me if averageing spectras gives any improvement in noise?
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    Biochemist? anyone who knows about blood?

    well i am doing Raman spectroscopy and chemometric in a quantitative investigation of a protein. We will try to do it non invasive, but first we will build a model for quantification in whole blood. therefor its critical that my plasma sample has some turbidity like whole blood. We have very...
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    Biochemist? anyone who knows about blood?

    I know that blood contains more than just plasma and red bloodcells., but only need to mix red blood cells and plasma. does this work with a anticoalating substrat or is the blood doing seveere chemistry when its done
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    Biochemist? anyone who knows about blood?

    Hello I have some 40 doses of frozen blood plasma from different people, I have to study the optics of wholeblood. Is it possible to just mix it with (lets say 40%) of fresh red blood cells. Will this do any harm the the biochemistry? In that case What if I'll do it by my self? just...
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    Where can I start learning about quantum physics?

    its just 2 different formulation of Newtons law. You need a well understanding of this and waves, especially the differential wave equation before you go quantum. I think you should read quantum physics and atomic physics before you go into particle physics
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