Questions tagged [fluorescence]
For questions relating to the radiation emitted by substances as a result of incident radiation.
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Brilliant fluorescent properties of Na2S(x) obtained from Na2SO3 or Na2S2O3
When $\ce{K2SO3}$ or $\ce{Na2SO3}$ is heated strongly by any method (in a flame, in an electric arc, on a metal plate in an induction heater), the resulting residue should be a mixture of $\ce{Na2SO4/...
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High voltage arc treatment leads to the appearance of fluorescent granules in soda baking. Perhaps it's the F-centers?
I have a high-voltage converter at home, consisting of a horizontal "flyback" transformer from an old tube TV, field-effect power transistors and a square-wave generator with adjustable ...
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Non-binding buffer at pKa of roughly 6 that dissolves in ethanol?
I'm trying to find a proper buffer for my experiment, which I'd appreciate some suggestions on. I have a solution in which I want to measure the concentration of magnesium ions using a fluorescent ...
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Strange Binding Curve DNA:Protein Interaction
So I did some DNA:Protein Interaction studies using Fluorescence Polarisation Assays. I have fluorescently labelled DNA and add my Protein of interest. Down below you see an exemplary plot of the ...
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How are these green, blue, and purple markers fluorescing under monochromatic 589nm (yellow) light?
I have some green, blue, and purple markers which clearly fluoresce under monochromatic light with a lower wavelength. Here they are illuminated by 589nm light emitted by a low pressure-sodium lamp (...
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Calculate IC50 from fluorescence kinetic
I have an assay in which a fluorescence signal is generated when the enzyme reaction progresses. The fluorescence signal increases until a maximum is reached. Than it keeps constant. The first 1 h ...
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What chemical(s) in peanut butter cause it to glow under UV light?
It is relatively well known that peanut butter glows in the dark under UV light (if you don't believe me, see this short YouTube demo by NileRed).
I've tried it myself and it is clearly a real thing.
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Detection of contamination from salicylic acid via either single excitation fluorometer or via absorbance
My colleague detected fluorescent contamination likely from salicylic acid in some water samples. I have made a new batch and want to check whether my new samples also have this contamination.
1. Can ...
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Compounds with fluorescence and/or phosphorescence, what can do both? [closed]
What else (besides benzophenone) can both do phosphorescence but not fluorescence, and what else can do both phosphorescence and fluorescence? For example, does pentacene can do both?
I'm reading that ...
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Why isn't residual standard deviation used in FQY analysis?
I've been measuring relative fluorescence quantum yield (hereafter FQY) for a photosensitive pigment. Most analytical articles and standard operating procedures (SOPs) I've read suggest taking the ...
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Lifetime components in phosphorescence decay
I'm studying the phosphorescence decay of diacetyl in acetonitrile (it has a high quantum yield of intersystem crossing). The fluorimeter than I'm employing has microsecond resolution and, since the ...
user78790
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Is vibronically resolved spontaneous emission temperature dependent, following a distribution defined by the canonical density operator?
Does the lifetime of a molecular excited electronic state, for example the $S_1$ state, suffice for thermal equilibration before spontaneous emission occurs?
For example the fluorescence of coumarine, ...
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Why is collagen fibre autofluorescent?
Why is collagen fibre autofluorescent? Proteins with increased amount of trp, tyr, phe tend to fluoresce but I don't think collagen fibre has increased percentage of any of them. Some say collagen ...
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Calculating total fluorescence based on thin slices in a slab
I am modeling an acid-base reaction that includes a fluorescence indicator. My simple model is a slab of acid next to a slab of base and so on. These slabs are very thin, typically less than 10 ...
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Excited states and emission lifetimes
I have some doubts about the nomenclature of the lifetimes. Are singlet and fluorescence lifetimes the same? As well as the triplet and phosphorescence lifetimes?
Also, can the triplet/phosphorescence ...
user78790