Questions tagged [dye]
For questions related to compounds for producing color (intentional or not).
33
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Choosing a transition metal catalyst instead of iron catalyst to investigate the degradation of methyl orange?
I was working on a dye degradation project for methyl orange (MO), using Fenton's Reaction. I plan on keeping a constant pH of 2. Normally, the reaction is done with an Iron catalyst, but at lower pH ...
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An investigation on the rate of degradation (in %) of Chrysoidine-Y dye, as measured by UV-Vis spectrophotometry
Planning to do an investigation on the rate of degradation (in %) of Chrysoidine-Y dye, using UV-Vis spectrophotometry. I am planning to take an approach of increasing the concentration of Hydrogen ...
- 1,528
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Azo dyes with different colours than Yellow, Orange and Red [closed]
Why are there just Azo dyes with colours of Yellow Orange and Red. Do the molecules become to be unstable with a greater pi-electron System? Every dye or indicator with other colours are'nt Azo dyes.
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What is the reaction between crystal violet and bleach (sodium hypochlorite) and what is the mechanism of its action against crystal violet?
I'm trying to find the reaction between bleach (sodium hypochlorite) and crystal violet, and need to find the mechanism of its action, as during my lab investigation the bleach did cause the crystal ...
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Comparison of two different coloured dyes using UV-vis spectra
I know that Both solutions are a shade of purple due to the lack of absorbances in the red and blue regions, however am I correct in thinking that the peak slightly to the right of the 2 in this ...
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What is the origin of the name JOE - the dye used to mark DNA sequences?
I came across an article where JOE - a dye used to mark DNA sequences was mentioned. It was also stated that no one knows the origin of the name for the dye. Does anyone here have any clue?
Thanks!
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How can I choose the right solvent to remove pigment from cotton
I’m trying to figure out how I might be able to dissolve a pigment without destroying the substrate(cotton, very thin). I don’t know the exact pigment, so it’s a guessing game. It is violet, I suspect ...
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Literature values for the molar absorptivity of Methylene Blue
I am having trouble finding literature values for the molar absorptivity of MB dye from a scientific journal, preferably one that is recent.
I am also having trouble finding an explanation for why MB ...
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0
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I need to test fabric for arsenic, and I've found 141-year-old guidance. Is it legit?
I'm a book and paper conservator, and a few years ago had four books to restore. Their endpapers were this gorgeous green silk, but they were badly dry rotted, and needed to be removed. I suspected ...
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DNA staining agent with good absorbance at 532 nm
I need to stain some double-stranded DNA with an intercalating fluorescent dye. For imaging, I am using a microscope setup equiped with a 532 nm green laser.
What is the staining agent of choice to ...
- 201
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Fluorophores with high quantum yield and low lifetime
Does anyone know of any fluorophore or family of fluorophores with a relatively high fluorescence quantum yield (larger than 0.1) and a short lifetime (below hundreds of picoseconds)?
I have been ...
- 161
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Why don't universal indicator solutions react with themselves?
Universal indicator is a pH indicator made of a solution of
water, 1-propanol, phenolphthalein, sodium hydroxide, methyl red, bromothymol blue, sodium bisulfite, and thymol blue
that exhibits ...
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1
answer
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Has anyone added dyes to a mixture about to separated by chromatography in order to visualize where the desired product lies?
Usually in preparative chromatography one needs to know when the desired substance to be separated is coming down the pike. Often this required some sophisticated instrumentation. But, it occurred to ...
2
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Why are colloidal sol particles of acidic dyes negatively charged and basic dyes positively charged, when it should be the other way round?
From NCERT Class 12 Chemistry; Sri Aurobindo Marg, New Delhi, India; January 2019; p. 136:
Colloidal solutions of basic dyes like methylene blue are positively charged whereas colloidal solutions of ...
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What replaced lead-based pigments? [closed]
In the 1960s and before, even black and white letters had some lead from the actual metallic letters used by typesetters—some rubbed off. Same thing with books printed before 1970 or so and libraries ...
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